linux/drivers/tty/serial
Pali Rohár 0c6cfc109e serial: mvebu-uart: fix tx lost characters at power off
commit 54ca955b5a upstream.

Commit c685af1108 ("serial: mvebu-uart: fix tx lost characters") fixed tx
lost characters at low baud rates but started causing tx lost characters
when kernel is going to power off or reboot.

TX_EMP tells us when transmit queue is empty therefore all characters were
transmitted. TX_RDY tells us when CPU can send a new character.

Therefore we need to use different check prior transmitting new character
and different check after all characters were sent.

This patch splits polling code into two functions: wait_for_xmitr() which
waits for TX_RDY and wait_for_xmite() which waits for TX_EMP.

When rebooting A3720 platform without this patch on UART is print only:
[   42.699�

And with this patch on UART is full output:
[   39.530216] reboot: Restarting system

Fixes: c685af1108 ("serial: mvebu-uart: fix tx lost characters")
Signed-off-by: Pali Rohár <pali@kernel.org>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20201223191931.18343-1-pali@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-27 11:05:40 +01:00
..
8250 serial: 8250_omap: Avoid FIFO corruption caused by MDR1 access 2020-12-30 11:25:43 +01:00
cpm_uart tty: serial: cpm_uart - fix init when SMC is relocated 2019-07-31 07:26:57 +02:00
jsm tty: serial: jsm: remove redundant pointer ch 2018-07-13 15:36:32 +02:00
21285.c tty: add SPDX identifiers to all remaining files in drivers/tty/ 2017-11-08 13:08:12 +01:00
altera_jtaguart.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
altera_uart.c serial: altera: set RRDY flag also without irq 2018-02-28 13:30:09 +01:00
amba-pl010.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
amba-pl011.c serial: pl011: Fix lockdep splat when handling magic-sysrq interrupt 2020-11-05 11:08:34 +01:00
amba-pl011.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
apbuart.c tty: add SPDX identifiers to all remaining files in drivers/tty/ 2017-11-08 13:08:12 +01:00
apbuart.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ar933x_uart.c serial: ar933x_uart: set UART_CS_{RX,TX}_READY_ORIDE 2020-03-11 14:14:48 +01:00
arc_uart.c serial: arc_uart: Fix out-of-bounds access through DT alias 2018-02-28 15:29:59 +01:00
atmel_serial.c tty/serial: atmel: manage shutdown in case of RS485 or ISO7816 mode 2020-02-28 16:38:48 +01:00
atmel_serial.h tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
bcm63xx_uart.c MIPS changes for 4.15 2017-11-15 11:36:08 -08:00
clps711x.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
digicolor-usart.c tty/serial: digicolor: Fix digicolor-usart already registered warning 2019-07-31 07:26:59 +02:00
dz.c tty: add SPDX identifiers to all remaining files in drivers/tty/ 2017-11-08 13:08:12 +01:00
dz.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
earlycon-arm-semihost.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
earlycon.c earlycon: Remove hardcoded port->uartclk initialization in of_setup_earlycon 2018-05-14 13:41:05 +02:00
efm32-uart.c tty: add SPDX identifiers to all remaining files in drivers/tty/ 2017-11-08 13:08:12 +01:00
fsl_lpuart.c tty: serial: fsl_lpuart: fix lpuart32_poll_get_char 2020-10-30 10:38:32 +01:00
icom.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
icom.h tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
ifx6x60.c serial: ifx6x60: add missed pm_runtime_disable 2019-12-13 08:51:01 +01:00
ifx6x60.h tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
imx.c tty: serial: imx: keep console clocks always on 2020-11-24 13:27:24 +01:00
ioc3_serial.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
ioc4_serial.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
ip22zilog.c tty: add SPDX identifiers to all remaining files in drivers/tty/ 2017-11-08 13:08:12 +01:00
ip22zilog.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Kconfig tty: serial: earlycon dependency 2020-10-29 09:55:08 +01:00
kgdb_nmi.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
kgdboc.c Disable kgdboc failed by echo space to /sys/module/kgdboc/parameters/kgdboc 2019-04-03 06:26:26 +02:00
lantiq.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
lpc32xx_hs.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
Makefile TTY/Serial driver patches for 4.17-rc1 2018-04-04 18:43:49 -07:00
max310x.c serial: max310x: Fix tx_empty() callback 2019-12-05 09:20:40 +01:00
max3100.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
mcf.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
men_z135_uart.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
meson_uart.c tty: serial: meson: fix typo in the "stop bit" register definition 2017-11-28 15:32:33 +01:00
mpc52xx_uart.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
mps2-uart.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
mpsc.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
msm_serial.c tty: serial: msm_serial: Fix lockup for sysrq and oops 2020-01-09 10:19:06 +01:00
mux.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
mvebu-uart.c serial: mvebu-uart: fix tx lost characters at power off 2021-01-27 11:05:40 +01:00
mxs-auart.c serial: mxs-auart: add missed iounmap() in probe failure and remove 2020-07-22 09:32:10 +02:00
netx-serial.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
omap-serial.c tty: omap-serial: Fix initial on-boot RTS GPIO level 2018-01-09 16:45:17 +01:00
owl-uart.c tty: serial: owl: Fix the link time qualifier of 'owl_uart_exit()' 2019-11-06 13:05:49 +01:00
pch_uart.c PCI: Move Rohm Vendor ID to generic list 2020-06-22 09:05:23 +02:00
pic32_uart.c serial: set suppress_bind_attrs flag only if builtin 2019-01-26 09:32:34 +01:00
pic32_uart.h tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
pmac_zilog.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
pmac_zilog.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pnx8xxx_uart.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
pxa.c serial: pxa: Fix an error handling path in 'serial_pxa_probe()' 2018-06-28 21:07:54 +09:00
qcom_geni_serial.c tty: serial: qcom_geni_serial: Drop __init from qcom_geni_console_setup 2020-09-09 19:04:23 +02:00
rp2.c treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
sa1100.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
samsung.c tty: serial: samsung: Correct clock selection logic 2020-10-01 13:14:44 +02:00
samsung.h tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
sb1250-duart.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
sc16is7xx.c sc16is7xx: Fix for "Unexpected interrupt: 8" 2019-11-06 13:05:15 +01:00
sccnxp.c headers: separate linux/mod_devicetable.h from linux/platform_device.h 2018-07-07 17:52:26 +02:00
serial_core.c serial_core: Check for port state when tty is in error state 2020-12-30 11:25:48 +01:00
serial_ks8695.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
serial_mctrl_gpio.c serial: mctrl_gpio: Check for NULL pointer 2019-11-06 13:05:52 +01:00
serial_mctrl_gpio.h tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
serial_txx9.c serial: txx9: add missing platform_driver_unregister() on error in serial_txx9_init 2020-11-10 12:36:00 +01:00
serial-tegra.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
sh-sci.c serial: sh-sci: Make sure status register SCxSR is read in correct sequence 2020-04-29 16:31:34 +02:00
sh-sci.h serial: sh-sci: Support for HSCIF RX sampling point adjustment 2018-04-23 10:08:18 +02:00
sirfsoc_uart.c serial: sirf: Fix out-of-bounds access through DT alias 2018-02-28 15:30:00 +01:00
sirfsoc_uart.h tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
sn_console.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
sprd_serial.c serial: sprd: correct the wrong sequence of arguments 2019-09-21 07:16:45 +02:00
st-asc.c tty: serial: simplify getting .drvdata 2018-04-22 17:29:43 +02:00
stm32-usart.c serial: stm32: fix clearing interrupt error flags 2020-01-27 14:51:22 +01:00
stm32-usart.h serial: stm32: fix rx data length when parity enabled 2020-01-27 14:50:50 +01:00
suncore.c drivers/tty: add missing of_node_put() 2018-12-21 14:15:18 +01:00
sunhv.c sunhv: Fix device naming inconsistency between sunhv_console and sunhv_reg 2019-06-22 08:15:14 +02:00
sunsab.c treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
sunsab.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
sunsu.c serial/sunsu: fix refcount leak 2019-01-13 09:51:03 +01:00
sunzilog.c tty: add SPDX identifiers to all remaining files in drivers/tty/ 2017-11-08 13:08:12 +01:00
sunzilog.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
timbuart.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
timbuart.h tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
uartlite.c serial: uartlite: fix exit path null pointer 2019-10-17 13:45:00 -07:00
ucc_uart.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
vr41xx_siu.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
vt8500_serial.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
xilinx_uartps.c serial: uartps: Wait for tx_empty in console setup 2020-10-01 13:14:42 +02:00
zs.c tty: add SPDX identifiers to all remaining files in drivers/tty/ 2017-11-08 13:08:12 +01:00
zs.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00