BRKINT is within c_iflag rather than c_cflag.
Fixes: ea017f5853 (tty: serial: uartlite: Prevent changing fixed parameters)
Reviewed-by: Sean Anderson <sean.anderson@seco.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220519081808.3776-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/tty/serial/cpm_uart/cpm_uart_core.c: In function ‘cpm_uart_init_port’:
drivers/tty/serial/cpm_uart/cpm_uart_core.c:1251:7: error: ‘udbg_port’ undeclared (first use in this function); did you mean ‘uart_port’?
if (!udbg_port)
^~~~~~~~~
uart_port
commit d142585bce leave this corner, wrap it with #ifdef block
Fixes: d142585bce ("serial: cpm_uart: Protect udbg definitions by CONFIG_SERIAL_CPM_CONSOLE")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20220518135452.39480-1-yuehaibing@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For the case of console_suspend disabled, if back to back suspend/resume
test is executed, at the end of test, sometimes console would appear to
be frozen not responding to input. This would happen because, during
resume, rx transactions can come in before system is ready, malfunction
of rx happens in turn resulting in console appearing to be stuck.
Do a stop_rx in suspend sequence to prevent this.
Signed-off-by: Vijaya Krishna Nivarthi <quic_vnivarth@quicinc.com>
Link: https://lore.kernel.org/r/1652692810-31148-1-git-send-email-quic_vnivarth@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Replace the UART frequency table 'root_freq[]' with logic around
clk_round_rate() so that SoC details like the available clk frequencies
can change and this driver still works. This reduces tight coupling
between this UART driver and the SoC clk driver because we no longer
have to update the 'root_freq[]' array for new SoCs. Instead the driver
determines the available frequencies at runtime.
Signed-off-by: Vijaya Krishna Nivarthi <quic_vnivarth@quicinc.com>
Link: https://lore.kernel.org/r/1652697510-30543-1-git-send-email-quic_vnivarth@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
SER_RS485_RTS_ON_SEND and SER_RS485_RTS_AFTER_SEND relate to behavior
within RS485 operation. The driver checks if they have the same value
which is not possible to realize with the hardware. The check is taken
regardless of SER_RS485_ENABLED flag and -EINVAL is returned when the
check fails, which creates problems.
This check makes it unnecessarily complicated to turn RS485 mode off as
simple zeroed serial_rs485 struct will trigger that equal values check.
In addition, the driver itself memsets its rs485 structure to zero when
RS485 is disabled but if userspace would try to make an TIOCSRS485
ioctl() call with the very same struct, it would end up failing with
-EINVAL which doesn't make much sense.
Resolve the problem by moving the check inside SER_RS485_ENABLED block.
Fixes: 7ecc77011c ("serial: 8250_fintek: Return -EINVAL on invalid configuration")
Cc: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/035c738-8ea5-8b17-b1d7-84a7b3aeaa51@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It was found that some MediaTek SoCs are incompatible with this
change. Also, this register was mistakenly understood as it was
related to the 16550A register layout selection but, at least
on some IPs, if not all, it's related to something else unknown.
This reverts commit 6f81fdded0.
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Fixes: 6f81fdded0 ("serial: 8250_mtk: Make sure to select the right FEATURE_SEL")
Reported-by: "kernelci.org bot" <bot@kernelci.org>
Link: https://lore.kernel.org/r/20220510122620.150342-1-angelogioacchino.delregno@collabora.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
__msm_console_write() assumes that interrupts are disabled, but
with threaded console printers it is possible that the write()
callback of the console is called with interrupts enabled.
Explicitly disable interrupts using local_irq_save() to preserve
the assumed context.
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20220506213324.470461-1-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The uart_ops startup() callback is called without interrupts
disabled and without port->lock locked, relatively late during the
boot process (from the call path of console_on_rootfs()). If the
device is a console, it was already previously registered and could
be actively printing messages.
Since the startup() callback is reading/writing registers used by
the console write() callback (AML_UART_CONTROL), its access must
be synchronized using the port->lock. Currently it is not.
The startup() callback is the only function that explicitly enables
interrupts. Without the synchronization, it is possible that
interrupts become accidentally permanently disabled.
CPU0 CPU1
meson_serial_console_write meson_uart_startup
-------------------------- ------------------
spin_lock(port->lock)
val = readl(AML_UART_CONTROL)
uart_console_write()
writel(INT_EN, AML_UART_CONTROL)
writel(val, AML_UART_CONTROL)
spin_unlock(port->lock)
Add port->lock synchronization to meson_uart_startup() to avoid
racing with meson_serial_console_write().
Also add detailed comments to meson_uart_reset() explaining why it
is *not* using port->lock synchronization.
Link: https://lore.kernel.org/lkml/2a82eae7-a256-f70c-fd82-4e510750906e@samsung.com
Fixes: ff7693d079 ("ARM: meson: serial: add MesonX SoC on-chip uart driver")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20220508103547.626355-1-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Slightly simplify ->probe() and drop a few goto labels by using
devm_add_action_or_reset() for clock and reset cleanup.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220509172129.37770-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The of_irq.h and of_platform.h are not used by the driver. On the
other hand, the mod_devicetable.h missed. Drop the former two and
add the latter one.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220509161911.37164-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use B0 to check zero baudrate rather than literal 0.
While at it, remove extra parenthesis around CBAUD.
Reviewed-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220513082906.11096-6-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
if (termios->c_cflag & CRTSCTS) guarantees that CRTSCTS is not ever set
in the else block so clearing it is unnecessary.
While at it, remove also one pair of extra parenthesis.
Reviewed-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220513082906.11096-5-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CMSPAR is defined by all architectures since commit 6bf08cb246
("[PATCH] Add CMSPAR to termbits.h for powerpc and alpha").
Reviewed-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220513082906.11096-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We were restoring the IRQ masks then clearing them again, because
ucon_mask wasn't set properly. Adding that makes suspend/resume
work as intended.
Signed-off-by: Hector Martin <marcan@marcan.st>
Link: https://lore.kernel.org/r/20220502092505.30934-1-marcan@marcan.st
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Don't report about the driver when loaded. It's unneeded and frowned
upon nowadays.
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220519075653.31356-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove debug printouts upon function enter/exit. This can be achieved
better by tracing.
Remove also the one protected by DEBUG_HARD which is not defined anyway.
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220519075653.31356-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
struct uart_pmac_port contains termios_cache. It is only written and
never read. Remove it as it only occupies space.
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220519075653.31356-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The support for DBDMA was never completed. Remove the the code that only
maps spaces without real work.
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220519075653.31356-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is no point keeping the header content separated. In this case, it
is only an enum. So move the enum to the appropriate source file.
Cc: Russell King <linux@armlinux.org.uk>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220519075720.31402-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If an irq is pending when devm_request_irq() is called, the irq
handler will cause a NULL pointer access because initialisation
is not done yet.
Fixes: 9d7ee0e28d ("tty: serial: lpuart: avoid report NULL interrupt")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Indan Zupancic <Indan.Zupancic@mep-info.com>
Link: https://lore.kernel.org/r/20220505114750.45423-1-Indan.Zupancic@mep-info.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The XON1/XOFF1 character registers are at offset 0xa0 and 0xa8
respectively, so we cannot use the definition in serial_port.h.
Fixes: bdbd0a7f8f ("serial: 8250-mtk: modify baudrate setting")
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20220427132328.228297-4-angelogioacchino.delregno@collabora.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Set the FEATURE_SEL at probe time to make sure that BIT(0) is enabled:
this guarantees that when the port is configured as AP UART, the
right register layout is interpreted by the UART IP.
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20220427132328.228297-3-angelogioacchino.delregno@collabora.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On MediaTek SoCs, the UART IP is 16550A compatible, but there are some
specific quirks: we are declaring a register shift of 2, but this is
only valid for the majority of the registers, as there are some that
are out of the standard layout.
Specifically, this driver is using definitions from serial_reg.h, where
we have a UART_EFR register defined as 2: this results in a 0x8 offset,
but there we have the FCR register instead.
The right offset for the EFR register on MediaTek UART is at 0x98,
so, following the decimal definition convention in serial_reg.h and
accounting for the register left shift of two, add and use the correct
register address for this IP, defined as decimal 38, so that the final
calculation results in (0x26 << 2) = 0x98.
Fixes: bdbd0a7f8f ("serial: 8250-mtk: modify baudrate setting")
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20220427132328.228297-2-angelogioacchino.delregno@collabora.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It will cause null-ptr-deref when using 'res', if platform_get_resource()
returns NULL, so move using 'res' after devm_ioremap_resource() that
will check it to avoid null-ptr-deref.
And use devm_platform_get_and_ioremap_resource() to simplify code.
Fixes: 5930cb3511 ("serial: driver for Conexant Digicolor USART")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Baruch Siach <baruch@tkos.co.il>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20220505124621.1592697-1-yangyingliang@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Given pop_tx() is a simple loop, inline it directly into handle_tx().
The code in handle_tx() looks much saner and straightforward now.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220503080808.28332-6-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1) take uart_tx_stopped into account every loop (the same as other uart
drivers)
2) no need for 'count' variable, operate on 'size' directly
This allows inlining this into handle_tx() nicely in the next patch.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220503080808.28332-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
One is in handle_tx() (as "min(xmit->head - xmit->tail, fifo_size))",
another one in pop_tx() (as uart_circ_empty(xmit)). So keep only the
latter.
This makes the code simpler and size variable is not needed now.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220503080808.28332-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It's horrid and if we inline it into callers, we can get rid of a lot of
sugar around.
So:
* x_char handling becomes a single iowrite8.
* xmit->buf handling is a single loop simply writing characters one by
one directly from the buf instead of complex cnt_to_end computations.
Until the buf is empty or fifo size is reached.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220503080808.28332-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When x_char is to be sent, the TX path overwrites whatever is in the
circular buffer at offset 0 with x_char and sends it using
pch_uart_hal_write(). I don't understand how this was supposed to work
if xmit->buf[0] already contained some character. It must have been
lost.
Remove this whole pop_tx_x() concept and do the work directly in the
callers. (Without printing anything using dev_dbg().)
Cc: <stable@vger.kernel.org>
Fixes: 3c6a483275 (Serial: EG20T: add PCH_UART driver)
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220503080808.28332-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
'count' is zero in the pop_tx()'s comparison against 'size'. So the 'if'
tries to find out if 'size' is negative or zero and returns in that
case. But it cannot be negative, due to previous (size < 0) check in the
caller: handle_tx().
So simply move this check from pop_tx() to handle_tx(). Now it's clear
that pop_tx() is called only if fifo_size is non-zero.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220503080613.27601-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
pic32_uart_startup() disables interrupts by local_irq_save(). But the
function never enables them. The serial core only holds a mutex, so irqs
are not restored.
So how could this driver work? This irq handling was already present in
the driver's initial commit 157b939470 (serial: pic32_uart: Add PIC32
UART driver).
So is it a candidate for removal? Anyone has a contact to the author:
Andrei Pistirica (I believe the one below -- @microchip.com -- will
bounce)? Or to someone else @microchip.com?
Cc: Andrei Pistirica <andrei.pistirica@microchip.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220503063122.20957-12-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
struct pic32_sport contains built-up names for irqs. These are freed
only in error path of pic32_uart_startup(). And even there, the freeing
happens before free_irq().
So fix this by:
* moving frees after free_irq(), and
* add frees to pic32_uart_shutdown() -- the opposite of
pic32_uart_startup().
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220503063122.20957-11-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
struct pic32_sport (sport) has just been kzallocated. So there is no
need to zero its member (sport->port) now.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220503063122.20957-10-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sport->cts_gpio is first assigned -EINVAL and few lines below using
of_get_named_gpio(). Remove the first (useless) assignment.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220503063122.20957-9-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
'c' is not in wrapped in parentheses in the to_pic32_sport() macro, so
it might be problematic wrt macro expansion. Using an inline is always
safer in these cases. Both type-wise and macro-expansion-wise. So switch
the macro to an inline.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220503063122.20957-8-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It's just &sport->port. First, sport was not in parenthesis, so macro
expansion could be an issue. Second, it's so simple, that we can expand
the macro and make the code really straightforward.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220503063122.20957-7-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make it a bool, so use true+false. And remove the wrap-around macro --
i.e. access the member directly.
It makes the code more obvious.
BTW the macro did not have 'sport' in parentheses, so it was potentially
problematic wrt expansion.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220503063122.20957-6-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
struct pic32_sport::ref_clk is only set, but not read. That means we can
remove it. And when we do so, pic32_enable_clock() and
pic32_disable_clock() are simple wrappers around clk_prepare_enable()
and clk_disable_unprepare() respectively. So we can remove the former
two from the code and replace it by the latter two.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220503063122.20957-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
All the irqflags_* in struct pic32_sport are set to IRQF_NO_THREAD and
never updated. So remove pic32_sport::irqflags_* and use the flag
directly.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220503063122.20957-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is no point keeping the header content separated. So move the
content to the appropriate source file.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220503063122.20957-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
struct pic32_console_opt and its support are unused in pic32. So remove
all that.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220503063122.20957-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In case the RS485 mode is emulated using GPIO RTS, use the TC interrupt
to deassert the GPIO RTS, otherwise the GPIO RTS stays asserted after a
transmission ended and the RS485 cannot work.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Alexandre Torgue <alexandre.torgue@foss.st.com>
Cc: Erwan Le Ray <erwan.leray@foss.st.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jean Philippe Romain <jean-philippe.romain@foss.st.com>
Cc: Valentin Caron <valentin.caron@foss.st.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-stm32@st-md-mailman.stormreply.com
To: linux-serial@vger.kernel.org
Link: https://lore.kernel.org/r/20220430162845.244655-2-marex@denx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull out the GPIO RTS enable and disable handling into separate function.
Limit the scope of GPIO RTS toggling only to GPIO emulated RS485 too.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Alexandre Torgue <alexandre.torgue@foss.st.com>
Cc: Erwan Le Ray <erwan.leray@foss.st.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jean Philippe Romain <jean-philippe.romain@foss.st.com>
Cc: Valentin Caron <valentin.caron@foss.st.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-stm32@st-md-mailman.stormreply.com
To: linux-serial@vger.kernel.org
Link: https://lore.kernel.org/r/20220430162845.244655-1-marex@denx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The `clkin_rate' member of `struct sifive_serial_port' now duplicates
`uartclk' from nested `struct uart_port', so use `uartclk' throughout
and remove `clkin_rate'.
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2204291656150.9383@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The base baud value reported is supposed to be the highest baud rate
that can be set for a serial port. The SiFive FU740-C000 SOC's on-chip
UART supports baud rates of up to 1/16 of the input clock rate, which is
the bus clock `tlclk'[1], often at 130MHz in the case of the HiFive
Unmatched board.
However the sifive UART driver reports a fixed value of 115200 instead:
10010000.serial: ttySIF0 at MMIO 0x10010000 (irq = 1, base_baud = 115200) is a SiFive UART v0
10011000.serial: ttySIF1 at MMIO 0x10011000 (irq = 2, base_baud = 115200) is a SiFive UART v0
even though we already support setting higher baud rates, e.g.:
$ tty
/dev/ttySIF1
$ stty speed
230400
The baud base value is computed by the serial core by dividing the UART
clock recorded in `struct uart_port' by 16, which is also the minimum
value of the clock divider supported, so correct the baud base value
reported by setting the UART clock recorded to the input clock rate
rather than 115200:
10010000.serial: ttySIF0 at MMIO 0x10010000 (irq = 1, base_baud = 8125000) is a SiFive UART v0
10011000.serial: ttySIF1 at MMIO 0x10011000 (irq = 2, base_baud = 8125000) is a SiFive UART v0
References:
[1] "SiFive FU740-C000 Manual", v1p3, SiFive, Inc., August 13, 2021,
Section 16.9 "Baud Rate Divisor Register (div)", pp.143-144
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Fixes: 1f1496a923 ("riscv: Fix sifive serial driver")
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2204291656280.9383@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Oxford Semiconductor PCIe (Tornado) 950 serial port devices are driven
by a fixed 62.5MHz clock input derived from the 100MHz PCI Express clock.
We currently drive the device using its default oversampling rate of 16
and the clock prescaler disabled, consequently yielding the baud base of
3906250. This base is inadequate for some of the high-speed baud rates
such as 460800bps, for which the closest rate possible can be obtained
by dividing the baud base by 8, yielding the baud rate of 488281.25bps,
which is off by 5.9638%. This is enough for data communication to break
with the remote end talking actual 460800bps, where missed stop bits
have been observed.
We can do better however, by taking advantage of a reduced oversampling
rate, which can be set to any integer value from 4 to 16 inclusive by
programming the TCR register, and by using the clock prescaler, which
can be set to any value from 1 to 63.875 in increments of 0.125 in the
CPR/CPR2 register pair. The prescaler has to be explicitly enabled
though by setting bit 7 in the MCR or otherwise it is bypassed (in the
enhanced mode that we enable) as if the value of 1 was used.
Make use of these features then as follows:
- Set the baud base to 15625000, reflecting the minimum oversampling
rate of 4 with the clock prescaler and divisor both set to 1.
- Override the `set_mctrl' and set the MCR shadow there so as to have
MCR[7] always set and have the 8250 core propagate these settings.
- Override the `get_divisor' handler and determine a good combination of
parameters by using a lookup table with predetermined value pairs of
the oversampling rate and the clock prescaler and finding a pair that
divides the input clock such that the quotient, when rounded to the
nearest integer, deviates the least from the exact result. Calculate
the clock divisor accordingly.
Scale the resulting oversampling rate (only by powers of two) if
possible so as to maximise it, reducing the divisor accordingly, and
avoid a divisor overflow for very low baud rates by scaling the
oversampling rate and/or the prescaler even if that causes some
accuracy loss.
Also handle the historic spd_cust feature so as to allow one to set
all the three parameters manually to arbitrary values, by keeping the
low 16 bits for the divisor and then putting TCR in bits 19:16 and
CPR/CPR2 in bits 28:20, sanitising the bit pattern supplied such as
to clamp CPR/CPR2 values between 0.000 and 0.875 inclusive to 33.875.
This preserves compatibility with any existing setups, that is where
requesting a custom divisor that only has any bits set among the low
16 the oversampling rate of 16 and the clock prescaler of 33.875 will
be used as with the original 8250.
Finally abuse the `frac' argument to store the determined bit patterns
for the TCR, CPR and CPR2 registers.
- Override the `set_divisor' handler so as to set the TCR, CPR and CPR2
registers from the `frac' value supplied. Set the divisor as usual.
With the baud base set to 15625000 and the unsigned 16-bit UART_DIV_MAX
limitation imposed by `serial8250_get_baud_rate' standard baud rates
below 300bps become unavailable in the regular way, e.g. the rate of
200bps requires the baud base to be divided by 78125 and that is beyond
the unsigned 16-bit range. The historic spd_cust feature can still be
used to obtain such rates if so required.
See Documentation/tty/device_drivers/oxsemi-tornado.rst for more details.
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2204181519450.9383@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make ICR access helpers available outside 8250_port.c, however retain
them as ordinary static functions so as not to regress code generation.
This is because `serial_icr_write' is currently automatically inlined by
GCC, however `serial_icr_read' is not. Making them both static inline
would grow code produced, e.g.:
$ i386-linux-gnu-size --format=gnu 8250_port-{old,new}.o
text data bss total filename
15065 3378 0 18443 8250_port-old.o
15289 3378 0 18667 8250_port-new.o
and:
$ riscv64-linux-gnu-size --format=gnu 8250_port-{old,new}.o
text data bss total filename
16980 5306 0 22286 8250_port-old.o
17124 5306 0 22430 8250_port-new.o
while making them external would needlessly add a new module interface
and lose the benefit from `serial_icr_write' getting inlined outside
8250_port.o.
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2204181517500.9383@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The EndRun PTP/1588 dual serial port device is based on the Oxford
Semiconductor OXPCIe952 UART device with the PCI vendor:device ID set
for EndRun Technologies and uses the same sequence to determine the
number of ports available. Despite that we have duplicate code
specific to the EndRun device.
Remove redundant code then and factor out OxSemi Tornado device
detection.
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2204181516220.9383@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The 8250 PXA driver never used Runtime PM, so there was never a need to
include <linux/pm_runtime.h>.
Fixes: ab28f51c77 ("serial: rewrite pxa2xx-uart to use 8250_core")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/9fd96fba9bbbbdeb16af0dc07ae9dee21c8e297c.1651494971.git.geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
dw8250_platform_data is only used on DT platforms for now.
Fixes: 4a218b277f ("serial: 8250: dw: Create a generic platform data structure")
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220502115621.77985-1-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Synopsys DesignWare UART can be configured to have HW support for
the RS485 protocol from IP version 4.0 onward. Add support for
hardware-controlled half duplex and full duplex modes.
HW will take care of managing DE and RE, the driver just gives it
permission to use either by setting both to 1.
To ask for full duplex mode, userspace sets SER_RS485_RX_DURING_TX flag
and HW will take care of the rest.
Set delay_rts_before_send and delay_rts_after_send to zero for now. The
granularity of that ABI is too coarse to be useful.
Co-developed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Co-developed-by: Raymond Tan <raymond.tan@intel.com>
Signed-off-by: Raymond Tan <raymond.tan@intel.com>
Co-developed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220426122448.38997-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add UART_CAP_NOTEMT for UARTs that lack interrupt on TEMT but want to
use em485. Em485 framework needs to ensure not only FIFO is empty but
also that tx shift register is empty.
This approach uses Uwe Kleine-König's suggestion on simply
using/incrementing stop_tx timer rather than adding another timer. When
UART_CAP_NOTEMT is set and THRE is present w/o TEMT, stop tx timer is
reused to wait for the emptying of the shift register.
This change does not add the UART_CAP_NOTEMT define as it already exist
but is currently no-op. See 7a107b2c6b (Revert "serial: 8250: Handle
UART without interrupt on TEMT using em485") for further details.
Vicente Bergas reported that RTS is deasserted roughly one bit too
early losing stop bit tx. To address this problem, stop_delay now
accounts for one extra bit using rough formula /7 (assumes worst-case
of 2+5 bits). I suspect this glitch had to do with when THRE is getting
asserted. If FIFO is emptied already during the tx of the stop bit,
perhaps it leads to HW asserting THRE early for the normal frame time
formula to work accurately.
Suggested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Eric Tremblay <etremblay@distech-controls.com>
Tested-by: Vicente Bergas <vicencb@gmail.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220425143410.12703-4-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8250 DMA tx complete path lacks calls to normal 8250 stop handling. It
does not use THRE to detect true completion of the tx and also doesn't
call __stop_tx. This leads to problems with em485 that needs to handle
RTS timing.
Instead of handling tx stop internally within 8250 dma code, enable
THRE when tx'able data runs out and tweak serial8250_handle_irq to call
only __stop_tx when uart is using DMA.
It also seems bit early to call serial8250_rpm_put_tx from there while
tx is still underway(?).
Tested-by: Vicente Bergas <vicencb@gmail.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220425143410.12703-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Struct uart_port currently stores FIFO timeout. Having character timing
information readily available is useful. Even serial core itself
determines char_time from port->timeout using inverse calculation.
Store frame_time directly into uart_port. Character time is stored in
nanoseconds to have reasonable precision with high rates. To avoid
overflow, 64-bit math is necessary.
It might be possible to determine timeout from frame_time by
multiplying it with fifosize as needed but only part of the users seem
to be protected by a lock. Thus, this patch does not pursue storing
only frame_time in uart_port.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220425143410.12703-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Renesas RZ/N1 SoC features a slightly modified DW UART.
On this SoC, the CPR register value is known but not synthetized in
hardware. We hence need to provide a CPR value in the platform
data. This version of the controller also relies on acting as flow
controller when using DMA, so we need to provide the
"is dma flow controller" quirk.
Co-developed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-10-miquel.raynal@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
DW based controllers like the one on Renesas RZ/N1 must be programmed as
flow controllers when using DMA.
* Table 11.45 of the system manual, "Flow Control Combinations", states
that using UART with DMA requires setting the DMA in the peripheral
flow controller mode regardless of the direction.
* Chapter 11.6.1.3 of the system manual, "Basic Interface Definitions",
explains that the burst size in the above case must be configured in
the peripheral's register DEST/SRC_BURST_SIZE.
Experiments shown that upon Rx timeout, the DMA transaction needed to be
manually cleared as well.
Co-developed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-9-miquel.raynal@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
These accessors should be used instead of the regular readl/writel()
helpers. In order to use them also from 8250_dw.c in this directory,
move the helpers to 8250_dwlib.h
There is no functional change.
There is no need for declaring `struct uart_port` or even UPIO_MEM32BE
which both are already included in the 8250_dwlib.h header by 8250.h.
Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-8-miquel.raynal@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In a next change we are going to need the same Rx timeout condition as
we already have in the IRQ handling code. Let's just create a boolean to
clarify what this operation does before reusing it.
There is no functional change.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-7-miquel.raynal@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
One situation where this could be used is when configuring the UART
controller to be the DMA flow controller. This is a typical case where
the driver might need to program a few more registers before starting a
DMA transfer. Provide the necessary infrastructure to support this
case.
Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-6-miquel.raynal@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
DW UART controllers can be synthesized without the CPR register.
In this case, allow to the platform information to provide a CPR value.
Co-developed-by: Phil Edworthy <phil.edworthy@renesas.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-5-miquel.raynal@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This offset is a good candidate to pdata's because it changes depending
on the vendor implementation. Let's move the usr_reg entry from regular
to pdata. This way we can drop initializing it at run time.
Let's also use a define for it instead of defining only the default
value.
Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-4-miquel.raynal@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use device tree match data rather than multiple calls to
of_device_is_compatible() by introducing a platform data structure and
adding a quirks mask.
Provide a stub to the compatibles without quirks to simplify the
handling of the upcoming changes.
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
[<miquel.raynal@bootlin.com: Minor changes + creation of a real pdata structure]
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-3-miquel.raynal@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Move the per-device structure and a helper out of the main .c file, into
a shared header as they will both be reused from another .c file.
There is no functional change.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
[miquel.raynal@bootlin.com: Extracted from a bigger change]
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-2-miquel.raynal@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The EndRun PTP/1588 dual serial port device is based on the Oxford
Semiconductor OXPCIe952 UART device with the PCI vendor:device ID set
for EndRun Technologies and is therefore driven by a fixed 62.5MHz clock
input derived from the 100MHz PCI Express clock. The clock rate is
divided by the oversampling rate of 16 as it is supplied to the baud
rate generator, yielding the baud base of 3906250.
Replace the incorrect baud base of 4000000 with the right value of
3906250 then, complementing commit 6cbe45d8ac ("serial: 8250: Correct
the clock for OxSemi PCIe devices").
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Cc: stable <stable@kernel.org>
Fixes: 1bc8cde46a ("8250_pci: Added driver for Endrun Technologies PTP PCIe card.")
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2204181515270.9383@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Sticky MCR bits are lost in console restoration if console suspending
has been disabled. This currently affects the AFE bit, which works in
combination with RTS which we set, so we want to make sure the UART
retains control of its FIFO where previously requested. Also specific
drivers may need other bits in the future.
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Fixes: 4516d50aab ("serial: 8250: Use canary to restart console after suspend")
Cc: stable@vger.kernel.org # v4.0+
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2204181518490.9383@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 927728a34f.
Once the uart_port->rs485->flag is set to SER_RS485_ENABLED, the port
should always work in RS485 mode. If users want the port to leave
RS485 mode, they need to call ioctl() to clear SER_RS485_ENABLED.
So here we shouldn't clear the RS485 bits in the shutdown().
Fixes: 927728a34f ("serial: sc16is7xx: Clear RS485 bits in the shutdown")
Signed-off-by: Hui Wang <hui.wang@canonical.com>
Link: https://lore.kernel.org/r/20220418094339.678144-1-hui.wang@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support for KGDB in stm32 serial driver by implementing characters
polling callbacks (poll_init, poll_get_char and poll_put_char).
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Signed-off-by: Jean Philippe Romain <jean-philippe.romain@foss.st.com>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20220419085330.1178925-3-valentin.caron@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Rework stm32_usart_console_putchar() function in order to anticipate
the case where the character can never be sent.
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20220419085330.1178925-2-valentin.caron@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Do not set timeout to twice the approximate amount of time to send the
entire FIFO if CTS is enabled. If the caller requested no timeout, e.g.
when userspace program called tcdrain(), then wait without any timeout.
Premature return from tcdrain() was observed on imx based system which
has 32 character long transmitter FIFO with hardware CTS handling.
Simple userspace application that reproduces problem has to:
* Open tty device, enable hardware flow control (CRTSCTS)
* Write data, e.g. 26 bytes
* Call tcdrain() to wait for the transmitter
* Close tty device
The other side of serial connection has to:
* Receive some data, e.g. 10 bytes
* Set RTS output (CTS input from sender perspective) inactive for
at least twice the port timeout
* Try to receive remaining data
Without this patch, userspace application will finish without any error
while the other side of connection will never receive remaining data.
Signed-off-by: Tomasz Moń <tomasz.mon@camlingroup.com>
Link: https://lore.kernel.org/r/20220228054911.1420221-1-tomasz.mon@camlingroup.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Note: I am using a small test app + driver located at [0] for the
problem description. serco is a driver whose write function dispatches
to the serial controller. sertest is a user-mode app that writes n bytes
to the serial console using the serco driver.
While investigating a bug in the RHEL kernel, I noticed that the serial
console throughput is way below the configured speed of 115200 bps in
a HP Proliant DL380 Gen9. I was expecting something above 10KB/s, but
I got 2.5KB/s.
$ time ./sertest -n 2500 /tmp/serco
real 0m0.997s
user 0m0.000s
sys 0m0.997s
With the help of the function tracer, I then noticed the serial
controller was taking around 410us seconds to dispatch one single byte:
$ trace-cmd record -p function_graph -g serial8250_console_write \
./sertest -n 1 /tmp/serco
$ trace-cmd report
| serial8250_console_write() {
0.384 us | _raw_spin_lock_irqsave();
1.836 us | io_serial_in();
1.667 us | io_serial_out();
| uart_console_write() {
| serial8250_console_putchar() {
| wait_for_xmitr() {
1.870 us | io_serial_in();
2.238 us | }
1.737 us | io_serial_out();
4.318 us | }
4.675 us | }
| wait_for_xmitr() {
1.635 us | io_serial_in();
| __const_udelay() {
1.125 us | delay_tsc();
1.429 us | }
...
...
...
1.683 us | io_serial_in();
| __const_udelay() {
1.248 us | delay_tsc();
1.486 us | }
1.671 us | io_serial_in();
411.342 us | }
In another machine, I measured a throughput of 11.5KB/s, with the serial
controller taking between 80-90us to send each byte. That matches the
expected throughput for a configuration of 115200 bps.
This patch changes the serial8250_console_write to use the 16550 fifo
if available. In my benchmarks I got around 25% improvement in the slow
machine, and no performance penalty in the fast machine.
Signed-off-by: Wander Lairson Costa <wander@redhat.com>
Link: https://lore.kernel.org/r/20220411174841.34936-2-wander@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is a deadlock in sa1100_set_termios(), which is shown
below:
(Thread 1) | (Thread 2)
| sa1100_enable_ms()
sa1100_set_termios() | mod_timer()
spin_lock_irqsave() //(1) | (wait a time)
... | sa1100_timeout()
del_timer_sync() | spin_lock_irqsave() //(2)
(wait timer to stop) | ...
We hold sport->port.lock in position (1) of thread 1 and
use del_timer_sync() to wait timer to stop, but timer handler
also need sport->port.lock in position (2) of thread 2. As a result,
sa1100_set_termios() will block forever.
This patch moves del_timer_sync() before spin_lock_irqsave()
in order to prevent the deadlock.
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Link: https://lore.kernel.org/r/20220417111626.7802-1-duoming@zju.edu.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
No need to initialize the count variable in lpuart_copy_rx_to_tty(),
so let's remove it here.
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20220418021844.29591-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some more serial drivers can be compile-tested under certain
circumstances (when building a specific architecture). So allow for
that.
This reduces the need of zillion mach/subarch-specific configs. And
since the 0day bot has only allmodconfig's for some archs, this
increases build coverage there too.
Note that cpm needs a minor update in the header, so that it drags in
at least some defines (CPM2 ones).
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421101708.5640-8-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
pic32_uart contains this:
#ifdef CONFIG_SERIAL_PIC32_CONSOLE
...
console_initcall(pic32_console_init);
...
core_initcall(pic32_late_console_init);
...
#endif
...
arch_initcall(pic32_uart_init);
When the driver is built as module, all three above become
module_init(). So if SERIAL_PIC32_CONSOLE is set while SERIAL_PIC32=m,
it results in the following build error:
In file included from include/linux/device/driver.h:21,
from include/linux/device.h:32,
from include/linux/platform_device.h:13,
from drivers/tty/serial/pic32_uart.c:12:
include/linux/module.h:131:49: error: redefinition of '__inittest'
So make sure SERIAL_PIC32_CONSOLE can be set only when SERIAL_PIC32=y --
similar as for other drivers.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421101708.5640-7-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The code wants to know if the circ buffer is empty, so use the proper
macro.
No functional change intended, just saner function name used for that
use case.
Cc: Andy Gross <agross@kernel.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421101708.5640-6-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
struct uart_port::membase is declared as a pointer. So it should be
initialized by NULL, not zero constant.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421101708.5640-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cache port->state->xmit into a local variable (xmit) in
cdns_uart_handle_tx(). This reduces length of some lines there
significantly. I.e. makes the code more readable.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421101708.5640-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Return from the true branch of the 'if'. This saves one indentation
level and makes the code more readable.
The two comments about what obvious code does are removed too.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421101708.5640-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Smatch reports this issue
sunplus-uart.c:501:26: warning: symbol 'sunplus_console_ports' was not declared. Should it be static?
sunplus_console_ports is only used in sunplus-uart.c so change
its storage-class specifier to static
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Tom Rix <trix@redhat.com>
Link: https://lore.kernel.org/r/20220421152505.1531507-1-trix@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make UART driver compatible with S4 SOC UART. Meanwhile, the S4 SOC
UART uses 12MHz as the clock source for baud rate calculations.
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Yu Tu <yu.tu@amlogic.com>
Link: https://lore.kernel.org/r/20220422111320.19234-3-yu.tu@amlogic.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A /2 divider over XTAL was introduced since G12A, and is preferred
to be used over the still present /3 divider since it provides much
closer frequencies vs the request baudrate. Especially the BT module
uses 3Mhz baud rate. 8Mhz calculations can lead to baud rate bias,
causing some problems.
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Yu Tu <yu.tu@amlogic.com>
Link: https://lore.kernel.org/r/20220422111320.19234-2-yu.tu@amlogic.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some members of struct icom_port are completely unused or only set and
never read. Remove all those.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-11-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
uart_ops::release_port() and uart_ops::request_port() are not required
by the serial layer. So no need to define empty ones.
Remove them.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-10-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use list_for_each_entry() helper instead of explicit combo of
list_for_each() and list_entry().
Note that pos is used as a reference point in list_add_tail() in
icom_alloc_adapter(). This functionality remains as with an empty list,
cur_adapter_entry->icom_adapter_entry is still the list head.
This simplifies the code a bit.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-9-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The baud rates are unsigned constants. So mark them as such.
Not only it makes sense, but they are passed also to
uart_get_baud_rate() and that expects unsigned int as baud rates on
input.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-8-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is no point keeping the header content separated. The header was
not even protected against double inclusion. So move the content to the
appropriate source file.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-6-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is a lot of sparse warnings:
.../icom.c:228:30: warning: cast from restricted __le16
.../icom.c:232:66: warning: incorrect type in assignment (different base types)
.../icom.c:232:66: expected unsigned int [usertype] leBuffer
.../icom.c:232:66: got restricted __le32 [usertype]
.../icom.c:237:30: warning: cast from restricted __le16
...
.../icom.c:1228:22: warning: cast from restricted __le16
And they are correct. So sort them all out by using proper __leXX and
uXX types and the right direction of conversion: le16_to_cpu() instead
of cpu_to_le16(), where appropriate.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Integrate both the to_icom_adapter() macro and icom_kref_release()
wrapper into icom_remove_adapter(). (And keep it icom_kref_release()
name.)
It makes the code easier to follow without complex indirections.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In icom, there is an ICOM_PORT macro to perform upcasts from struct
uart_port to struct icom_port. It's not completely safe and it works
only because the first member of icom_port is uart_port. Nowadays, we
use container_of for such an upcast instead.
So introduce a helper (to_icom_port()) with container_of in it and
convert all the ICOM_PORT users to the new helper. Apart from the code
and type safety, it's also clear what icom_port (the variable) is.
Unlike with the old ICOM_PORT (the macro with the cast).
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As a preparation for cleaning up the omap1 headers, start
including linux/soc/ti/omap1-soc.h directly so we can
keep calling cpu_is_omap1510().
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This partially reverts commit f6f586102a. The code added by
that commit containted math overflow for 32-bit archs. In
addition, the approach used in it is unnecessarily complicated
requiring a dedicated timer just for notemt. A simpler approach
for providing UART_CAP_NOTEMT already exists (patches 1-2):
https://lore.kernel.org/linux-serial/20220411083321.9131-3-ilpo.jarvinen@linux.intel.com/T/#u
Thus, simply revert the UART_CAP_NOTEMT change for now.
There were two driver changes within the patch series adding
UART_CAP_NOTEMT taking advantage of the newly added flag.
This does not revert the driver changes and therefore also
UART_CAP_NOTEMT define has to remain. UART_CAP_NOTEMT remains
no-op until support is again added.
Fixes: f6f586102a ("serial: 8250: Handle UART without interrupt on TEMT using em485")
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/5f874142-fb1f-bff7-f33-fac823e65e2e@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The i.MX DMA drivers are device tree only, nothing in
include/linux/platform_data/dma-imx.h has platform_data in it, so move
the file to include/linux/dma/imx-dma.h.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-By: Vinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/20220414162249.3934543-10-s.hauer@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Commit 932d596378 ("serial: 8250: Return early in .start_tx() if there
are no chars to send") caused a regression where the drivers implementing
runtime PM stopped idling. This is because serial8250_rpm_put_tx() is now
unbalanced on early return, it normally gets called at __stop_tx().
Fixes: 932d596378 ("serial: 8250: Return early in .start_tx() if there are no chars to send")
Cc: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20220411111657.16744-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 76821e222c ("serial: imx: ensure that RX irqs are off if RX is
off") accidentally enabled overrun interrupts unconditionally when
deferring DMA enable until after the receiver has been enabled during
startup.
Fix this by using the DMA-initialised instead of DMA-enabled flag to
determine whether overrun interrupts should be enabled.
Note that overrun interrupts are already accounted for in
imx_uart_clear_rx_errors() when using DMA since commit 41d98b5da9
("serial: imx-serial - update RX error counters when DMA is used").
Fixes: 76821e222c ("serial: imx: ensure that RX irqs are off if RX is off")
Cc: stable@vger.kernel.org # 4.17
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20220411081957.7846-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current timeout for draining the tx fifo in RS485 mode is calculated by
multiplying the time it takes to transmit one character (with the given
baud rate) with the maximal number of characters in the tx queue.
This timeout is too short for two reasons:
First when calculating the time to transmit one character integer division
is used which may round down the result in case of a remainder of the
division.
Fix this by rounding up the division result.
Second the hardware may need additional time (e.g for first putting the
characters from the fifo into the shift register) before the characters are
actually put onto the wire.
To be on the safe side double the current maximum number of iterations
that are used to wait for the queue draining.
Fixes: 8d47923772 ("serial: amba-pl011: add RS485 support")
Cc: stable@vger.kernel.org
Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220408233503.7251-1-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now fsl_lpuart driver use both of_alias_get_id() and ida_simple_get() in
.probe(), which has the potential bug. For example, when remove the
lpuart7 alias in dts, of_alias_get_id() will return error, then call
ida_simple_get() to allocate the id 0 for lpuart7, this may confilct
with the lpuart4 which has alias 0.
aliases {
...
serial0 = &lpuart4;
serial1 = &lpuart5;
serial2 = &lpuart6;
serial3 = &lpuart7;
}
So remove the ida_simple_get() in .probe(), return an error directly
when calling of_alias_get_id() fails, which is consistent with other
uart drivers behavior.
Fixes: 3bc3206e1c ("serial: fsl_lpuart: Remove the alias node dependence")
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20220321112211.8895-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When flow control is enabled, the UART should set RTS to false
during suspend to stop incoming data. Currently, the suspend
routine sets the mctrl register in the uart to zero, but leaves
the shadow version in the uart_port struct alone so that resume
can restore it. This causes a problem later in suspend when
serial8250_do_shutdown() is called which uses the shadow mctrl
register to clear some additional bits but ends up restoring RTS.
The solution is to clear RTS from the shadow version before
serial8250_do_shutdown() is called and restore it after.
Signed-off-by: Al Cooper <alcooperx@comcast.net>
Link: https://lore.kernel.org/r/20220324145620.41573-1-alcooperx@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Freescale variant of the 16550A doesn't have an interrupt on TEMT
available when using the FIFO mode.
Signed-off-by: Eric Tremblay <etremblay@distech-controls.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220330104642.229507-3-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Introduce the UART_CAP_NOTEMT capability. The capability indicates that
the UART doesn't have an interrupt available on TEMT.
In the case where the device does not support it, we calculate the
maximum time it could take for the transmitter to empty the
shift register. When we get in the situation where we get the
THRE interrupt, we check if the TEMT bit is set. If it's not, we start
the a timer and recall __stop_tx() after the delay.
The transmit sequence is a bit modified when the capability is set. The
new timer is used between the last interrupt(THRE) and a potential
stop_tx timer.
Signed-off-by: Giulio Benetti <giulio.benetti@micronovasrl.com>
[moved to use added UART_CAP_TEMT]
Signed-off-by: Heiko Stuebner <heiko.stuebner@theobroma-systems.com>
[moved to use added UART_CAP_NOTEMT, improve timeout]
Signed-off-by: Eric Tremblay <etremblay@distech-controls.com>
[rebased to v5.17, making use of tty_get_frame_size]
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220330104642.229507-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
platform_get_resource() may fail and return NULL, so we should
better check it's return value to avoid a NULL pointer dereference.
Fixes: 54da3e381c ("serial: 8250_aspeed_vuart: use UPF_IOREMAP to set up register mapping")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Link: https://lore.kernel.org/r/20220404143842.16960-1-linmq006@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In uart_set_rs485_config() the serial core already assigns the passed
serial_rs485 struct to the uart port.
So remove the assignment from the drivers rs485_config() function to avoid
redundancy.
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-10-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In uart_set_rs485_config() the serial core already ensures that only one of
both options RTS on send or RTS after send is set. It also assigns the
passed serial_rs485 struct to the uart port.
So remove the check and the assignment from the drivers rs485_config()
function to avoid redundancy.
Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-9-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In uart_set_rs485_config() the serial core already assigns the passed
serial_rs485 struct to the uart port.
So remove the assignment in the drivers rs485_config() function to avoid
reduncancy.
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-8-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In uart_set_rs485_config() the serial core already nullifies the padding
field of the passed serial_rs485 struct before returning it to userspace.
Doing the same in the drivers rs485_config() function is redundant, so
remove the concerning memset in this function.
Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-7-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In uart_set_rs485_config() the serial core already clamps the RTS delays.
It also assigns the passed serial_rs485 struct to the uart port.
So remove these tasks from the drivers rs485_config() function to avoid
redundancy.
Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-6-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In uart_set_rs485_config() the serial core already ensures that only one of
both options RTS on send or RTS after send is set.
So remove this check from the drivers rs485_config() function to avoid
redundancy.
Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-5-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In uart_set_rs485_config() the serial core already ensures that only one of
both options RTS on send or RTS after send is set. It also assigns the
passed serial_rs485 struct to the uart port.
So remove the check and the assignment from the drivers rs485_config()
function to avoid redundancy.
Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-4-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In uart_set_rs485_config() the serial core already
- ensures that only one of both options RTS on send or RTS after send is
set
- nullifies the padding field of the passed serial_rs485 struct
- clamps the RTS delays
- assigns the passed serial_rs485 struct to the uart port
So remove these tasks from the code of the drivers rs485_config() function
to avoid redundancy.
Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-3-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Several drivers that support setting the RS485 configuration via userspace
implement one or more of the following tasks:
- in case of an invalid RTS configuration (both RTS after send and RTS on
send set or both unset) fall back to enable RTS on send and disable RTS
after send
- nullify the padding field of the returned serial_rs485 struct
- copy the configuration into the uart port struct
- limit RTS delays to 100 ms
Move these tasks into the serial core to make them generic and to provide
a consistent behaviour among all drivers.
Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-2-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Due to chip process differences, chip designers recommend using baud
rates as close to and larger as possible in order to reduce clock
errors.
Signed-off-by: Yu Tu <yu.tu@amlogic.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lore.kernel.org/r/20220407081355.13602-2-yu.tu@amlogic.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Provide information in the kernel log as to what configuration option to
enable for PCI UART devices that have been blacklisted in the generic
PCI 8250 UART driver and which have a dedicated driver available to
handle that has been disabled. The rationale is there is no easy way
for the user to map a specific PCI vendor:device pair to an individual
dedicated driver while the generic driver has this information readily
available and it will likely be confusing that the generic driver does
not register such a port.
This is unlike usual drivers, such as drivers/net/ethernet/3com/3c59x.c
which handles all the hardware family members regardless of differences
between them, and following an existing example where a serio driver
provides suggestions as to the correct configuration options to use:
psmouse serio1: synaptics: The touchpad can support a better bus than the too old PS/2 protocol. Make sure MOUSE_PS2_SYNAPTICS_SMBUS and RMI4_SMB are enabled to get a better touchpad experience.
A message is then printed like:
serial 0000:04:00.3: ignoring port, enable SERIAL_8250_PERICOM to handle
when an affected device is encountered and the generic driver rejects it.
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2203310054120.44113@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is needed for the Renesas RZ/V2M (r9a09g011) SoC.
Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220330154024.112270-6-phil.edworthy@renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The console_write and IRQ handler can run concurrently.
Problems may occurs console_write is continuously executed while
the IRQ handler is running.
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
Link: https://lore.kernel.org/r/20220407071619.102249-2-jaewon02.kim@samsung.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
altera_jtaguart_tx_chars() duplicates what altera_jtaguart_stop_tx()
already does. So instead of the duplication, call the helper instead.
Not only it makes the code cleaner, but it also says what the "if"
really does.
Cc: Tobias Klauser <tklauser@distanz.ch>
Acked-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220411104506.8990-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Flow control characters should be sent even if the TX is stopped. So fix
owl-uart to behave the same as other drivers.
This unification also allows the use of the TX helper in the future.
Cc: "Andreas Färber" <afaerber@suse.de>
Cc: Manivannan Sadhasivam <mani@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220411104506.8990-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The code now contains:
#ifdef CONFIG_PPC_MPC512x
...
#endif
#ifdef CONFIG_PPC_MPC512x
...
#endif
So remove the endif+ifdef from the middle, provided it's about the same
define.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220411104506.8990-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* 'remove-h8300' of git://git.infradead.org/users/hch/misc:
remove the h8300 architecture
This is clearly the least actively maintained architecture we have at
the moment, and probably the least useful. It is now the only one that
does not support MMUs at all, and most of the boards only support 4MB
of RAM, out of which the defconfig kernel needs more than half just
for .text/.data.
Guenter Roeck did the original patch to remove the architecture in 2013
after it had already been obsolete for a while, and Yoshinori Sato brought
it back in a much more modern form in 2015. Looking at the git history
since the reinstantiation, it's clear that almost all commits in the tree
are build fixes or cross-architecture cleanups:
$ git log --no-merges --format=%an v4.5.. arch/h8300/ | sort | uniq
-c | sort -rn | head -n 12
25 Masahiro Yamada
18 Christoph Hellwig
14 Mike Rapoport
9 Arnd Bergmann
8 Mark Rutland
7 Peter Zijlstra
6 Kees Cook
6 Ingo Molnar
6 Al Viro
5 Randy Dunlap
4 Yury Norov
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The below commit changed types of some hooks in struct psc_ops. It also
changed the types of the functions which are referenced in the instances
of the above struct.
However the commit did so only for CONFIG_PPC_MPC52xx, but not for
CONFIG_PPC_MPC512x. This results in build errors like:
mpc52xx_uart.c:static unsigned int mpc52xx_psc_raw_tx_rdy(struct uart_port *port)
mpc52xx_uart.c:static int mpc512x_psc_raw_tx_rdy(struct uart_port *port)
^^^
mpc52xx_uart.c:static int mpc5125_psc_raw_tx_rdy(struct uart_port *port)
^^^
Therefore, fix the latter case now too.
Fixes: 18662a1d8f (tty: serial: mpc52xx_uart: make rx/tx hooks return unsigned)
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220404055122.31194-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here are the big set of tty and serial driver changes for 5.18-rc1.
Nothing major, some more good cleanups from Jiri and 2 new serial
drivers. Highlights include:
- termbits cleanups
- export symbol cleanups and other core cleanups from Jiri Slaby
- new sunplus and mvebu uart drivers (amazing that people are
still creating new uarts...)
- samsung serial driver cleanups
- ldisc 29 is now "reserved" for experimental/development line
disciplines
- lots of other tiny fixes and cleanups to serial drivers and
bindings
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial driver updates from Greg KH:
"Here are the big set of tty and serial driver changes for 5.18-rc1.
Nothing major, some more good cleanups from Jiri and 2 new serial
drivers. Highlights include:
- termbits cleanups
- export symbol cleanups and other core cleanups from Jiri Slaby
- new sunplus and mvebu uart drivers (amazing that people are still
creating new uarts...)
- samsung serial driver cleanups
- ldisc 29 is now "reserved" for experimental/development line
disciplines
- lots of other tiny fixes and cleanups to serial drivers and
bindings
All of these have been in linux-next for a while with no reported
issues"
* tag 'tty-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (104 commits)
vt_ioctl: fix potential spectre v1 in VT_DISALLOCATE
serial: 8250: fix XOFF/XON sending when DMA is used
tty: serial: samsung: Add ARTPEC-8 support
dt-bindings: serial: samsung: Add ARTPEC-8 UART
serial: sc16is7xx: Clear RS485 bits in the shutdown
tty: serial: samsung: simplify getting OF match data
tty: serial: samsung: constify variables and pointers
tty: serial: samsung: constify s3c24xx_serial_drv_data members
tty: serial: samsung: constify UART name
tty: serial: samsung: constify s3c24xx_serial_drv_data
tty: serial: samsung: reduce number of casts
tty: serial: samsung: embed s3c2410_uartcfg in parent structure
tty: serial: samsung: embed s3c24xx_uart_info in parent structure
serial: 8250_tegra: mark acpi_device_id as unused with !ACPI
tty: serial: bcm63xx: use more precise Kconfig symbol
serial: SERIAL_SUNPLUS should depend on ARCH_SUNPLUS
tty: serial: jsm: fix two assignments in if conditions
tty: serial: jsm: remove redundant assignments to variable linestatus
serial: 8250_mtk: make two read-only arrays static const
serial: samsung_tty: do not unlock port->lock for uart_write_wakeup()
...
The overwhelming bulk of this pull request is a change from Uwe
Kleine-König which changes the return type of the remove() function to
void as part of some wider work he's doing to do this for all bus types,
causing updates to most SPI device drivers. The branch with that on has
been cross merged with a couple of other trees which added new SPI
drivers this cycle, I'm not expecting any build issues resulting from
the change.
Otherwise it's been a relatively quiet release with some new device
support, a few minor features and the welcome completion of the
conversion of the subsystem to use GPIO descriptors rather than numbers:
- Change return type of remove() to void.
- Completion of the conversion of SPI controller drivers to use GPIO
descriptors rather than numbers.
- Quite a few DT schema conversions.
- Support for multiple SPI devices on a bus in ACPI systems.
- Big overhaul of the PXA2xx SPI driver.
- Support for AMD AMDI0062, Intel Raptor Lake, Mediatek MT7986 and
MT8186, nVidia Tegra210 and Tegra234, Renesas RZ/V2L, Tesla FSD and
Sunplus SP7021.
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Merge tag 'spi-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi updates from Mark Brown:
"The overwhelming bulk of this pull request is a change from Uwe
Kleine-König which changes the return type of the remove() function to
void as part of some wider work he's doing to do this for all bus
types, causing updates to most SPI device drivers. The branch with
that on has been cross merged with a couple of other trees which added
new SPI drivers this cycle, I'm not expecting any build issues
resulting from the change.
Otherwise it's been a relatively quiet release with some new device
support, a few minor features and the welcome completion of the
conversion of the subsystem to use GPIO descriptors rather than
numbers:
- Change return type of remove() to void.
- Completion of the conversion of SPI controller drivers to use GPIO
descriptors rather than numbers.
- Quite a few DT schema conversions.
- Support for multiple SPI devices on a bus in ACPI systems.
- Big overhaul of the PXA2xx SPI driver.
- Support for AMD AMDI0062, Intel Raptor Lake, Mediatek MT7986 and
MT8186, nVidia Tegra210 and Tegra234, Renesas RZ/V2L, Tesla FSD and
Sunplus SP7021"
[ And this is obviously where that spi change that snuck into the
regulator tree _should_ have been :^]
* tag 'spi-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (124 commits)
spi: fsi: Implement a timeout for polling status
spi: Fix erroneous sgs value with min_t()
spi: tegra20: Use of_device_get_match_data()
spi: mediatek: add ipm design support for MT7986
spi: Add compatible for MT7986
spi: sun4i: fix typos in comments
spi: mediatek: support tick_delay without enhance_timing
spi: Update clock-names property for arm pl022
spi: rockchip-sfc: fix platform_get_irq.cocci warning
spi: s3c64xx: Add spi port configuration for Tesla FSD SoC
spi: dt-bindings: samsung: Add fsd spi compatible
spi: topcliff-pch: Prevent usage of potentially stale DMA device
spi: tegra210-quad: combined sequence mode
spi: tegra210-quad: add acpi support
spi: npcm-fiu: Fix typo ("npxm")
spi: Fix Tegra QSPI example
spi: qup: replace spin_lock_irqsave by spin_lock in hard IRQ
spi: cadence: fix platform_get_irq.cocci warning
spi: Update NXP Flexspi maintainer details
dt-bindings: mfd: maxim,max77802: Convert to dtschema
...
When 8250 UART is using DMA, x_char (XON/XOFF) is never sent
to the wire. After this change, x_char is injected correctly.
Create uart_xchar_out() helper for sending the x_char out and
accounting related to it. It seems that almost every driver
does these same steps with x_char. Except for 8250, however,
almost all currently lack .serial_out so they cannot immediately
take advantage of this new helper.
The downside of this patch is that it might reintroduce
the problems some devices faced with mixed DMA/non-DMA transfer
which caused revert f967fc8f16 (Revert "serial: 8250_dma:
don't bother DMA with small transfers"). However, the impact
should be limited to cases with XON/XOFF (that didn't work
with DMA capable devices to begin with so this problem is not
very likely to cause a major issue, if any at all).
Fixes: 9ee4b83e51 ("serial: 8250: Add support for dmaengine")
Reported-by: Gilles Buloz <gilles.buloz@kontron.com>
Tested-by: Gilles Buloz <gilles.buloz@kontron.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220314091432.4288-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support for the UART block on the ARTPEC-8 SoC. This is closely
related to the variants used on the Exynos chips. The register layout
is identical to Exynos850 et al but the fifo size is different (64 bytes
in each direction for all instances).
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Link: https://lore.kernel.org/r/20220311094515.3223023-3-vincent.whitchurch@axis.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We tested RS485 function on an EVB which has SC16IS752, after
finishing the test, we started the RS232 function test, but found the
RTS is still working in the RS485 mode.
That is because both startup and shutdown call port_update() to set
the EFCR_REG, this will not clear the RS485 bits once the bits are set
in the reconf_rs485(). To fix it, clear the RS485 bits in shutdown.
Cc: <stable@vger.kernel.org>
Signed-off-by: Hui Wang <hui.wang@canonical.com>
Link: https://lore.kernel.org/r/20220308110042.108451-1-hui.wang@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Simplify the code with of_device_get_match_data() and use dev_of_node()
to remove ifdef-erry.
Tested-by: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20220308080919.152715-9-krzysztof.kozlowski@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Constify variables, data pointed by several pointers and
"udivslot_table" static array. This makes code a bit safer.
Tested-by: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20220308080919.152715-8-krzysztof.kozlowski@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver data (struct s3c24xx_serial_drv_data) is never modified, so
also its members can be made const. Except code style this has no
impact because the structure itself is always a const.
Tested-by: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20220308080919.152715-7-krzysztof.kozlowski@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The UART name from driver data holds only string literals.
Tested-by: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20220308080919.152715-6-krzysztof.kozlowski@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver data (struct s3c24xx_serial_drv_data) is only used to
initialize the driver properly and is not modified. Make it const.
Tested-by: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20220308080919.152715-5-krzysztof.kozlowski@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The pointers to instances of "struct s3c24xx_serial_drv_data" are first
cast to kernel_ulong_t and then either used directly
(in "platform_device_id.driver_data") or cast again to void * (in
"of_device_id.data").
One cast can be dropped, so at least for "of_device_id.data" case there
will be no casts at all. This makes the code a bit simpler.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20220308080919.152715-4-krzysztof.kozlowski@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Embed "struct s3c2410_uartcfg" directly as a member of "struct
s3c24xx_serial_drv_data" instead of keeping it as a pointer. This makes
the code clearer (obvious ownership of "s3c2410_uartcfg
s3c24xx_serial_drv_data") and saves one pointer.
Tested-by: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20220308080919.152715-3-krzysztof.kozlowski@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Embed "struct s3c24xx_uart_info" directly as a member of "struct
s3c24xx_serial_drv_data" instead of keeping it as a pointer. This makes
the code clearer (obvious ownership of "struct s3c24xx_serial_drv_data")
and saves one pointer.
Tested-by: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20220308080919.152715-2-krzysztof.kozlowski@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver's acpi_device_id table is referenced via ACPI_PTR() so it
will be unused for !CONFIG_ACPI builds:
drivers/tty/serial/8250/8250_tegra.c:178:36:
warning: ‘tegra_uart_acpi_match’ defined but not used [-Wunused-const-variable=]
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20220308074157.113568-1-krzysztof.kozlowski@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Sunplus serial ports are only present on Sunplus SoCs. Hence add a
dependency on ARCH_SUNPLUS, to prevent asking the user about this driver
when configuring a kernel without Sunplus SoC support.
Fixes: 9e8d547032 ("serial: sunplus-uart: Add Sunplus SoC UART Driver")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/59f46272ab5b16853acac4d585c3333cfd394223.1647352195.git.geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Variable linestatus is being assigned values that are never read, the
assignments are redundant and can be removed.
Cleans up clang scan warnings:
drivers/tty/serial/jsm/jsm_cls.c:369:2: warning: Value stored to
'linestatus' is never read [deadcode.DeadStores]
drivers/tty/serial/jsm/jsm_cls.c:400:4: warning: Value stored to
'linestatus' is never read [deadcode.DeadStores]
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://lore.kernel.org/r/20220307153047.139639-1-colin.i.king@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Don't populate the read-only arrays fraction_L_mapping and
fraction_M_mapping on the stack but instead make them static
const. Also makes the object code a little smaller.
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://lore.kernel.org/r/20220307230055.168241-1-colin.i.king@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The commit c15c3747ee (serial: samsung: fix potential soft lockup
during uart write) added an unlock of port->lock before
uart_write_wakeup() and a lock after it. It was always problematic to
write data from tty_ldisc_ops::write_wakeup and it was even documented
that way. We fixed the line disciplines to conform to this recently.
So if there is still a missed one, we should fix them instead of this
workaround.
On the top of that, s3c24xx_serial_tx_dma_complete() in this driver
still holds the port->lock while calling uart_write_wakeup().
So revert the wrap added by the commit above.
Cc: Thomas Abraham <thomas.abraham@linaro.org>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Hyeonkook Kim <hk619.kim@samsung.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220308115153.4225-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It's only a wrapper to struct uart_port, so unwrap the whole code.
No change in functionality is intended.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220307054348.31748-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
__setup() handlers should return 1 to obsolete_checksetup() in
init/main.c to indicate that the boot option has been handled.
A return of 0 causes the boot option/value to be listed as an Unknown
kernel parameter and added to init's (limited) environment strings.
So return 1 from kgdboc_option_setup().
Unknown kernel command line parameters "BOOT_IMAGE=/boot/bzImage-517rc7
kgdboc=kbd kgdbts=", will be passed to user space.
Run /sbin/init as init process
with arguments:
/sbin/init
with environment:
HOME=/
TERM=linux
BOOT_IMAGE=/boot/bzImage-517rc7
kgdboc=kbd
kgdbts=
Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru
Fixes: 1bd54d851f ("kgdboc: Passing ekgdboc to command line causes panic")
Fixes: f2d937f3bf ("consoles: polling support, kgdboc")
Cc: He Zhe <zhe.he@windriver.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: kgdb-bugreport@lists.sourceforge.net
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: linux-serial@vger.kernel.org
Reported-by: Igor Zhbanov <i.zhbanov@omprussia.ru>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20220309033018.17936-1-rdunlap@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The 'kgdboc_earlycon_init' looks for boot console that has both .read
and .write callbacks. Adds 'samsung_early_read' to samsung_tty.c's early
console to support kgdboc.
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: Woody Lin <woodylin@google.com>
Link: https://lore.kernel.org/r/20220302114923.144523-1-woodylin@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, uart_console_write->putchar's second parameter (the
character) is of type int. It makes little sense, provided uart_console_write()
accepts the input string as "const char *s" and passes its content -- the
characters -- to putchar(). So switch the character's type to unsigned
char.
We don't use char as that is signed on some platforms. That would cause
troubles for drivers which (implicitly) cast the char to u16 when
writing to the device. Sign extension would happen in that case and the
value written would be completely different to the provided char. DZ is
an example of such a driver -- on MIPS, it uses u16 for dz_out in
dz_console_putchar().
Note we do the char -> uchar conversion implicitly in
uart_console_write(). Provided we do not change size of the data type,
sign extension does not happen there, so the problem is void.
This makes the types consistent and unified with the rest of the uart
layer, which uses unsigned char in most places already. One exception is
xmit_buf, but that is going to be converted later.
Cc: Paul Cercueil <paul@crapouillou.net>
Cc: Tobias Klauser <tklauser@distanz.ch>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Ludovic Desroches <ludovic.desroches@microchip.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: bcm-kernel-feedback-list@broadcom.com
Cc: Alexander Shiyan <shc_work@mail.ru>
Cc: Baruch Siach <baruch@tkos.co.il>
Cc: "Maciej W. Rozycki" <macro@orcam.me.uk>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: NXP Linux Team <linux-imx@nxp.com>
Cc: Karol Gugala <kgugala@antmicro.com>
Cc: Mateusz Holenko <mholenko@antmicro.com>
Cc: Vladimir Zapolskiy <vz@mleia.com>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Jerome Brunet <jbrunet@baylibre.com>
Cc: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Cc: Taichi Sugaya <sugaya.taichi@socionext.com>
Cc: Takao Orito <orito.takao@socionext.com>
Cc: Liviu Dudau <liviu.dudau@arm.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: "Andreas Färber" <afaerber@suse.de>
Cc: Manivannan Sadhasivam <mani@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Andy Gross <agross@kernel.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Cc: Orson Zhai <orsonzhai@gmail.com>
Cc: Baolin Wang <baolin.wang7@gmail.com>
Cc: Chunyan Zhang <zhang.lyra@gmail.com>
Cc: Patrice Chotard <patrice.chotard@foss.st.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@foss.st.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Peter Korsgaard <peter@korsgaard.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Acked-by: Richard Genoud <richard.genoud@gmail.com> [atmel_serial]
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Paul Cercueil <paul@crapouillou.net>
Acked-by: Neil Armstrong <narmstrong@baylibre.com> # meson_serial
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220303080831.21783-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In case of error, the function devm_ioremap() returns NULL pointer
not ERR_PTR(). The IS_ERR() test in the return value check should
be replaced with NULL test.
Fixes: b7e2b5360f ("serial: mvebu-uart: implement UART clock driver for configuring UART base clock")
Reported-by: Hulk Robot <hulkci@huawei.com>
Reviewed-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Link: https://lore.kernel.org/r/20220301075806.3950108-1-weiyongjun1@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Let serial core know that the chip automatically handles RTS/CTS signal.
This elimines completely unnecessary I2C/SPI bus traffic.
Cease reading from RX FIFO (by disabling RDI interrupt) when throttled.
Eventually the FIFO will fill up and the device will drive RTS output
inactive. Unthrottle by enabling back RDI interrupt.
Indirectly controlling RTS via RX FIFO state seems to be the only option
because RTS bit is ignored when hardware flow control is enabled.
Signed-off-by: Tomasz Moń <tomasz.mon@camlingroup.com>
Link: https://lore.kernel.org/r/20220301060332.2561851-4-tomasz.mon@camlingroup.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The uart_handle_cts_change() and uart_handle_dcd_change() must be called
with port lock being held. Acquire the lock after reading MSR register.
Do not acquire spin lock when reading MSR register because I2C/SPI port
functions cannot be called with spinlocks held.
Update rng and dsr counters. Wake up delta_msr_wait to allow tty notice
modem status change.
Co-developed-by: Lech Perczak <l.perczak@camlintechnologies.com>
Co-developed-by: Tomasz Moń <tomasz.mon@camlingroup.com>
Signed-off-by: Lech Perczak <l.perczak@camlintechnologies.com>
Signed-off-by: Tomasz Moń <tomasz.mon@camlingroup.com>
Link: https://lore.kernel.org/r/20220301060332.2561851-3-tomasz.mon@camlingroup.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sc16is7xx_stop_tx() clears THRI bit and thus disables THRI interrupt.
This makes it possible for transmission to cease indefinitely when more
than 64 characters are being sent.
The sc16is7xx_handle_tx() call executed by sc16is7xx_tx_proc() can send
up to FIFO length (64) characters. If more characters are written to the
output buffer, then the THRI interrupt is needed.
Solve the issue by enabling THRI interrupt in sc16is7xx_tx_proc().
Signed-off-by: Tomasz Moń <tomasz.mon@camlingroup.com>
Link: https://lore.kernel.org/r/20220301060332.2561851-2-tomasz.mon@camlingroup.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts the following commits:
31979060cc tty: serial: meson: Fix the compile link error reported by kernel test robot
5427c352a9 tty: serial: meson: Added S4 SOC compatibility
19b2ba0baf tty: serial: meson: The system stuck when you run the stty command on the console to change the baud rate
e5fc2b9984 tty: serial: meson: Make some bit of the REG5 register writable
44023b8e1f tty: serial: meson: Describes the calculation of the UART baud rate clock using a clock frame
6436dd8f9b tty: serial: meson: Use devm_ioremap_resource to get register mapped memory
841f913e77 tty: serial: meson: Move request the register region to probe
They seem to cause lots of problems with existing hardware platforms,
and caused build issues, so revert the whole series all at once.
Link: https://lore.kernel.org/r/849a95fd-ae81-9a3b-0c06-dd7826af9eb2@baylibre.com
Link: https://lore.kernel.org/all/20220225073922.3947-1-yu.tu@amlogic.com/
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reported-by: Jerome Brunet <jbrunet@baylibre.com>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Yu Tu <yu.tu@amlogic.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Describes the calculation of the UART baud rate clock using a clock
frame. Forgot to add in Kconfig kernel test Robot compilation error
due to COMMON_CLK dependency.
Fixes: 44023b8e1f ("tty: serial: meson: Describes the calculation of the UART baud rate clock using a clock frame")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Yu Tu <yu.tu@amlogic.com>
Link: https://lore.kernel.org/r/20220228064910.11636-1-yu.tu@amlogic.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Having a generic UART_LCR_WLEN() macro and the tty_get_char_size()
helper, we can remove all those repeated switch-cases in drivers.
Cc: Laxman Dewangan <ldewangan@nvidia.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: linux-tegra@vger.kernel.org
Reviewed-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220224095558.30929-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add Sunplus SoC UART Driver.
SP7021 UART block contains 5 UARTs.
There are UART0~4 that supported in SP7021, the features list as below.
Support Full-duplex communication.
Support data packet length configurable.
Support stop bit number configurable.
Support force break condition.
Support baud rate configurable.
Support error detection and report.
Support RXD Noise Rejection Vote configurable.
UART0 pinout only support TX/RX two pins.
UART1 to UART4 pinout support TX/RX/CTS/RTS four pins.
Normally UART0 used for kernel console, also can be used for normal uart.
Command line set "console=ttySUP0,115200", SUP means Sunplus Uart Port.
UART driver probe will create path named "/dev/ttySUPx".
https://sunplus.atlassian.net/wiki/spaces/doc/pages/1873412290/13.+Universal+Asynchronous+Receiver+Transmitter+UART
Signed-off-by: Hammer Hsieh <hammerh0314@gmail.com>
Link: https://lore.kernel.org/r/1645522563-17183-3-git-send-email-hammerh0314@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Set em485->active_timer = NULL isn't always enough to take out the stop
timer. While there is a check that it acts in the right state (i.e.
waiting for RTS-after-send to pass after sending some chars) but the
following might happen:
- CPU1: some chars send, shifter becomes empty, stop tx timer armed
- CPU0: more chars send before RTS-after-send expired
- CPU0: shifter empty irq, port lock taken
- CPU1: tx timer triggers, waits for port lock
- CPU0: em485->active_timer = &em485->stop_tx_timer, hrtimer_start(),
releases lock()
- CPU1: get lock, see em485->active_timer == &em485->stop_tx_timer,
tear down RTS too early
This fix bases on research done by Steffen Trumtrar.
Fixes: b86f86e8e7 ("serial: 8250: fix potential deadlock in rs485-mode")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220215160236.344236-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Start the console and run the following commands in turn:
stty -F /dev/ttyAML0 115200 and stty -F /dev/ttyAML0 921600. The
system will stuck.
Signed-off-by: Yu Tu <yu.tu@amlogic.com>
Link: https://lore.kernel.org/r/20220225073922.3947-6-yu.tu@amlogic.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make the internal clock source mux and divider writeable, allowing the
uart to deviate from the settings intially applied by the ROMCode and
using the most appropriate clocks.
Signed-off-by: Yu Tu <yu.tu@amlogic.com>
Link: https://lore.kernel.org/r/20220225073922.3947-5-yu.tu@amlogic.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Using the common Clock code to describe the UART baud rate clock
makes it easier for the UART driver to be compatible with the
baud rate requirements of the UART IP on different meson chips.
Signed-off-by: Yu Tu <yu.tu@amlogic.com>
Link: https://lore.kernel.org/r/20220225073922.3947-4-yu.tu@amlogic.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Replace devm_request_mem_region and devm_ioremap with
devm_ioremap_resource to make the code cleaner.
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Yu Tu <yu.tu@amlogic.com>
Link: https://lore.kernel.org/r/20220225073922.3947-3-yu.tu@amlogic.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This simplifies resetting the UART controller during probe
and will make it easier to integrate the common clock code
which will require the registers at probe time as well.
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Yu Tu <yu.tu@amlogic.com>
Link: https://lore.kernel.org/r/20220225073922.3947-2-yu.tu@amlogic.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here are some small n_gsm and sc16is7xx serial driver fixes for
5.17-rc6.
The n_gsm fixes are from Siemens as it seems they are using the line
discipline and fixing up a number of issues they found in their testing.
The sc16is7xx serial driver fix is for a reported problem with that
chip.
All of these have been in linux-next with no reported problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-5.17-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial driver fixes from Greg KH:
"Here are some small n_gsm and sc16is7xx serial driver fixes for
5.17-rc6.
The n_gsm fixes are from Siemens as it seems they are using the line
discipline and fixing up a number of issues they found in their
testing. The sc16is7xx serial driver fix is for a reported problem
with that chip.
All of these have been in linux-next with no reported problems"
* tag 'tty-5.17-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
sc16is7xx: Fix for incorrect data being transmitted
tty: n_gsm: fix deadlock in gsmtty_open()
tty: n_gsm: fix wrong modem processing in convergence layer type 2
tty: n_gsm: fix wrong tty control line for flow control
tty: n_gsm: fix NULL pointer access due to DLCI release
tty: n_gsm: fix proper link termination after failed open
tty: n_gsm: fix encoding of command/response bit
tty: n_gsm: fix encoding of control signal octet bit DV
The code uses uart_amba_port::port on many places. Sometimes it even
needs not uart_amba_port itself. So simplify the code on many places
and remove the need of uart_amba_port on some places completely.
No functional changes intended. The objdump -d output shows only a code
move in pl010_rx_chars().
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Russell King <linux@armlinux.org.uk>
Link: https://lore.kernel.org/r/20220224111028.20917-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove the hello print among with version and name definitions. Drivers
should print nothing if they are successful.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220224111028.20917-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
All these return bitmasks, so it makes more sense to return unsigned --
this is what a reader and also all the callers expect.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220224111028.20917-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The pci_get_slot() increases its reference count, the caller
must decrement the reference count by calling pci_dev_put().
Fixes: 9a1870ce81 ("serial: 8250: don't use slave_id of dma_slave_config")
Depends-on: a13e19cf3d ("serial: 8250_lpss: split LPSS driver to separate module")
Reported-by: Qing Wang <wangqing@vivo.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220223151240.70248-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The pci_get_slot() increases its reference count, the caller
must decrement the reference count by calling pci_dev_put().
Fixes: 90b9aacf91 ("serial: 8250_pci: add Intel Tangier support")
Fixes: f549e94eff ("serial: 8250_pci: add Intel Penwell ports")
Reported-by: Qing Wang <wangqing@vivo.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Depends-on: d9eda9bab2 ("serial: 8250_pci: Intel MID UART support to its own driver")
Link: https://lore.kernel.org/r/20220215100920.41984-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
coccinelle report:
./drivers/tty/serial/8250/8250_aspeed_vuart.c:85:8-16:
WARNING: use scnprintf or sprintf
./drivers/tty/serial/8250/8250_aspeed_vuart.c:174:8-16:
WARNING: use scnprintf or sprintf
./drivers/tty/serial/8250/8250_aspeed_vuart.c:127:8-16:
WARNING: use scnprintf or sprintf
Use sysfs_emit instead of scnprintf or sprintf makes more sense.
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Yang Guang <yang.guang5@zte.com.cn>
Signed-off-by: David Yang <davidcomponentone@gmail.com>
Link: https://lore.kernel.org/r/fed40753603dac4d14b17970c88e6f5f936348c1.1644541843.git.yang.guang5@zte.com.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Correct the Kconfig help text for SERIAL_8250_LPSS, SERIAL_8250_MID and
SERIAL_8250_PERICOM configuration options for dedicated PCI UART drivers
that have been blacklisted in the generic PCI 8250 UART driver and as
from commit a13e19cf3d ("serial: 8250_lpss: split LPSS driver to
separate module"), commit d9eda9bab2 ("serial: 8250_pci: Intel MID
UART support to its own driver"), and commit fcfd3c09f4 ("serial:
8250_pci: Split out Pericom driver") respectively are not handled by
said driver anymore (rather than for extra features only, as the current
text indicates), and therefore require the respective dedicated drivers
to work at all.
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2202121704560.34636@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Implement simple usage of fractional divisor. When main divisor D is too
large to represent requested baudrate then use divisor M from the
fractional divisor feature. All the M prescalers are set to the same and
maximal value 63, so the fractional part of the fractional divisor is not
used at all. We also determine upper limit for possible baudrates.
Experiments show that UART at baudrate 1500000 Bd with this configuration
is stable. So there is no need to implement complicated calculation of
fractional coefficients yet.
To use this feature with higher baudrates, it is required to use UART clock
provided by UART clock driver. Default boot xtal clock is not capable of
higher baudrates.
Reviewed-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
Link: https://lore.kernel.org/r/20220219152818.4319-6-kabel@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Implement a new device driver for controlling UART clocks on Marvell
Armada 3700 SoC. This device driver is loaded for devices which match
the compatible string "marvell,armada-3700-uart-clock".
There are more pitfalls related to UART clocks:
- both UARTs use same parent clock source (which can be xtal or one of
the TBG clocks),
- if a TBG clock is used as the parent clock, there are two additional
divisors that can both be configured to divide the rate by 1, 2, ... 6,
but these divisors are again shared between the two UART controllers
on the SOC,
- the configuration of the parent clock source and divisors is done in
the address space of the first UART controller, UART1. Clocks can be
gated separately for UART1 and UART2, but this setting also lives in
the address space of UART1,
- Marvell's Functional Specification for Armada 3720 document has the
clock gating bits swapped, so the one described to gate UART1 clock
actually gates UART2 and vice versa,
- each UART has it's own "special divisor", and this uses the parent
clock described above. These divisors are configure in each UART's
address space separately.
Thus the driver for UART2 controller needs to have access to UART1
address space, since UART1 address space contains some bits exclusive
for UART2 and also some bits which are shared between UART1 and UART2.
Also, during boot, when early console is active on one of the UARTs,
and we want to switch parent clock from xtal (default) to TBG (to be
more flexible with baudrates), the driver changing UART clocks also
needs to be able to change the "special divisor", so that the baudrate
of earlycon is not changed when swtiching to normal console. Thus the
clock driver also needs to be able to access UART2 register space,
for UART2's "special divisor".
For these reasons, this new UART clock driver does not use
ioremap_resource(), but only ioremap() to prevent resource conflicts
between UART clock driver and UART driver.
We need to share only two 32-bit registers between the UART driver and
the UART clock driver:
- UART Clock Control
- UART 2 Baud Rate Divisor
Access to these two registers are protected by one spinlock to prevent
any conflicts. Access is required only during probing, when changing
baudrate or during suspend/resume.
Hardware can be configured to use one of following clocks as UART parent
clock: TBG-A-P, TBG-B-P, TBG-A-S, TBG-B-S, xtal. Not every clock is
usable for higher buadrates. Any subset can be specified in the
device-tree and the driver will choose the best one which also still
supports the mandatory baudrate of 9600 Bd. For smooth boot log output
it is needed to specify clock used by early console, otherwise garbage
would be printed on UART during probe of UART clock driver and
transitioning from early console to normal console.
We are implementing this to be able to configure TBG clock as UART
parent clock, which is required to be able to achieve higher baudrates
than 230400 Bd. We achieve this by referencing this new UART clock
device node in UART's device node. UART clock device driver
automatically chooses the best clock source for UART driver.
Until now, UART's device-tree node needed to reference one of the static
clocks (xtal or one of the TBGs) as parent clock in the `clocks`
phandle - the parent clock which was configured before booting the
kernel. If bootloader changed UART's parent clock, it needed to change
the `clocks` phandle in DTB correspondingly before booting.
From now on both the old mechanism (xtal or TBG referenced as parent
clock in `clocks` phandle) and the new one (UART clock referenced in the
`clocks` phandle) are supported, to provide full backward compatibility
with existing DTS files, full backward compatibility with existing boot
loaders, and to provide new features (runtime clock configuration to
allow higher baudrates than 230400 Bd). New features are available only
with new DTS files.
There was also a discussion about how the UART node and the
clock-controller node could be wrapped together in a new binding [1, 2].
As explained there, this is not possible if we want to keep backwards
compatibility with existing bootloaders, and thus we are doing this by
putting the UART clock-controller node inside the UART1 node.
[1] https://lore.kernel.org/linux-serial/20220120000651.in7s6nazif5qjkme@pali/
[2] https://lore.kernel.org/linux-serial/20220125204006.A6D09C340E0@smtp.kernel.org/
Reviewed-by: Marek Behún <kabel@kernel.org>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
Link: https://lore.kernel.org/r/20220219152818.4319-4-kabel@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Export only the GPIOs that are not shared with hardware modem control
lines. Introduce new device parameter indicating whether modem control
lines are available.
Signed-off-by: Lech Perczak <l.perczak@camlintechnologies.com>
Signed-off-by: Tomasz Moń <tomasz.mon@camlingroup.com>
Link: https://lore.kernel.org/r/20220221105618.3503470-4-tomasz.mon@camlingroup.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
RTS, DTR and LOOP bits can be updated in a single MCR register update.
This reduces the number of (slow) SPI/I2C bus transactions.
Signed-off-by: Lech Perczak <l.perczak@camlintechnologies.com>
Signed-off-by: Tomasz Moń <tomasz.mon@camlingroup.com>
Link: https://lore.kernel.org/r/20220221105618.3503470-3-tomasz.mon@camlingroup.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Preserve unaffected bits state when accessing EFR register. This
prevents hardware flow control bits from being cleared on enhanced
functions access.
Signed-off-by: Lech Perczak <l.perczak@camlintechnologies.com>
Signed-off-by: Tomasz Moń <tomasz.mon@camlingroup.com>
Link: https://lore.kernel.org/r/20220221105618.3503470-2-tomasz.mon@camlingroup.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Don't start the whole chain for TX if there is no data to send. This is
mostly relevant for rs485 mode as there might be rts-before-send and
rts-after-send delays involved.
Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220217211839.443039-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
UART drivers are meant to use the port spinlock within certain
methods, to protect against reentrancy. The sc16is7xx driver does
very little locking, presumably because when added it triggers
"scheduling while atomic" errors. This is due to the use of mutexes
within the regmap abstraction layer, and the mutex implementation's
habit of sleeping the current thread while waiting for access.
Unfortunately this lack of interlocking can lead to corruption of
outbound data, which occurs when the buffer used for I2C transmission
is used simultaneously by two threads - a work queue thread running
sc16is7xx_tx_proc, and an IRQ thread in sc16is7xx_port_irq, both
of which can call sc16is7xx_handle_tx.
An earlier patch added efr_lock, a mutex that controls access to the
EFR register. This mutex is already claimed in the IRQ handler, and
all that is required is to claim the same mutex in sc16is7xx_tx_proc.
See: https://github.com/raspberrypi/linux/issues/4885
Fixes: 6393ff1c44 ("sc16is7xx: Use threaded IRQ")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Phil Elwell <phil@raspberrypi.com>
Link: https://lore.kernel.org/r/20220216160802.1026013-1-phil@raspberrypi.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 54da3e381c ("serial: 8250_aspeed_vuart: use UPF_IOREMAP to
set up register mapping") fixed a bug that had, as a side-effect,
prevented the 8250_aspeed_vuart driver from enabling the VUART's
FIFOs. However, fixing that (and hence enabling the FIFOs) has in
turn revealed what appears to be a hardware bug in the ASPEED VUART in
which the host-side THRE bit doesn't get if the BMC-side receive FIFO
trigger level is set to anything but one byte. This causes problems
for polled-mode writes from the host -- for example, Linux kernel
console writes proceed at a glacial pace (less than 100 bytes per
second) because the write path waits for a 10ms timeout to expire
after every character instead of being able to continue on to the next
character upon seeing THRE asserted. (GRUB behaves similarly.)
As a workaround, introduce a new port type for the ASPEED VUART that's
identical to PORT_16550A as it had previously been using, but with
UART_FCR_R_TRIG_00 instead to set the receive FIFO trigger level to
one byte, which (experimentally) seems to avoid the problematic THRE
behavior.
Fixes: 54da3e381c ("serial: 8250_aspeed_vuart: use UPF_IOREMAP to set up register mapping")
Tested-by: Konstantin Aladyshev <aladyshev22@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Link: https://lore.kernel.org/r/20220211004203.14915-1-zev@bewilderbeest.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
All supported platforms by this driver require ->setup() and ->exit().
Remove unneeded test for ->setup() presence.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220215101111.47250-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since PCI core provides a generic PCI_DEVICE_DATA() macro,
replace MID_DEVICE() with former one.
No functional change intended.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220215104126.7220-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add early console support which relies on the bootloader for the
initialization of the UART.
Please note, that the compatibles are taken from at91-usart MFD
driver.
Tested-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20220217094620.1148571-1-michael@walle.cc
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
- Fix miscompilations when function calls are made from inside a
put_user() call
- Drop __init from map_pages() declaration to avoid random boot crashes
- Added #error messages if a 64-bit compiler was used to build a 32-bit
kernel (and vice versa)
- Fix out-of-bound data TLB miss faults in sba_iommu and ccio-dma
drivers
- Add ioread64_lo_hi() and iowrite64_lo_hi() functions to avoid kernel
test robot errors
- Fix link failure when 8250_gsc driver is built without CONFIG_IOSAPIC
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Merge tag 'for-5.17/parisc-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc architecture fixes from Helge Deller:
- Fix miscompilations when function calls are made from inside a
put_user() call
- Drop __init from map_pages() declaration to avoid random boot crashes
- Added #error messages if a 64-bit compiler was used to build a 32-bit
kernel (and vice versa)
- Fix out-of-bound data TLB miss faults in sba_iommu and ccio-dma
drivers
- Add ioread64_lo_hi() and iowrite64_lo_hi() functions to avoid kernel
test robot errors
- Fix link failure when 8250_gsc driver is built without CONFIG_IOSAPIC
* tag 'for-5.17/parisc-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
serial: parisc: GSC: fix build when IOSAPIC is not set
parisc: Fix some apparent put_user() failures
parisc: Show error if wrong 32/64-bit compiler is being used
parisc: Add ioread64_lo_hi() and iowrite64_lo_hi()
parisc: Fix sglist access in ccio-dma.c
parisc: Fix data TLB miss in sba_unmap_sg
parisc: Drop __init from map_pages declaration
There is a build error when using a kernel .config file from
'kernel test robot' for a different build problem:
hppa64-linux-ld: drivers/tty/serial/8250/8250_gsc.o: in function `.LC3':
(.data.rel.ro+0x18): undefined reference to `iosapic_serial_irq'
when:
CONFIG_GSC=y
CONFIG_SERIO_GSCPS2=y
CONFIG_SERIAL_8250_GSC=y
CONFIG_PCI is not set
and hence PCI_LBA is not set.
IOSAPIC depends on PCI_LBA, so IOSAPIC is not set/enabled.
Make the use of iosapic_serial_irq() conditional to fix the build error.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: kernel test robot <lkp@intel.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-serial@vger.kernel.org
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Johan Hovold <johan@kernel.org>
Suggested-by: Helge Deller <deller@gmx.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>
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Merge 5.17-rc4 into tty-next
We need the tty/serial fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Right now, even when `delay_rts_before_send` and `delay_rts_after_send`
are 0, the hrtimer is triggered (with timeout 0) which can introduce a
few 100us of additional overhead on slower i.MX platforms.
Implement a fast path when the delays are 0, where the RTS signal is
toggled immediately instead of going through an hrtimer. This fast path
behaves identical to the code before delay support was implemented.
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Harald Seiler <hws@denx.de>
Link: https://lore.kernel.org/r/20220119145204.238767-1-hws@denx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The value returned by an spi driver's remove function is mostly ignored.
(Only an error message is printed if the value is non-zero that the
error is ignored.)
So change the prototype of the remove function to return no value. This
way driver authors are not tempted to assume that passing an error to
the upper layer is a good idea. All drivers are adapted accordingly.
There is no intended change of behaviour, all callbacks were prepared to
return 0 before.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Acked-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Claudius Heine <ch@denx.de>
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # For MMC
Acked-by: Marcus Folkesson <marcus.folkesson@gmail.com>
Acked-by: Łukasz Stelmach <l.stelmach@samsung.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20220123175201.34839-6-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
