Zhiyong Tao c03cef6715 serial: 8250_mtk: fix uart corruption issue when rx power off ... commit 7c4a509d38 upstream. Fix uart corruption issue when rx power off. Add spin lock in mtk8250_dma_rx_complete function in APDMA mode. when uart is used as a communication port with external device(GPS). when external device(GPS) power off, the power of rx pin is also from 1.8v to 0v. Even if there is not any data in rx. But uart rx pin can capture the data "0". If uart don't receive any data in specified cycle, uart will generates BI(Break interrupt) interrupt. If external device(GPS) power off, we found that BI interrupt appeared continuously and very frequently. When uart interrupt type is BI, uart IRQ handler(8250 framwork API:serial8250_handle_irq) will push data to tty buffer. mtk8250_dma_rx_complete is a task of mtk_uart_apdma_rx_handler. mtk8250_dma_rx_complete priority is lower than uart irq handler(serial8250_handle_irq). if we are in process of mtk8250_dma_rx_complete, uart appear BI interrupt:1)serial8250_handle_irq will priority execution.2)it may cause write tty buffer conflict in mtk8250_dma_rx_complete. So the spin lock protect the rx receive data process is not break. Signed-off-by: Zhiyong Tao <zhiyong.tao@mediatek.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20210729084640.17613-2-zhiyong.tao@mediatek.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2021-08-12 13:22:15 +02:00
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hvc
ipwireless
serdev
serial	serial: 8250_mtk: fix uart corruption issue when rx power off	2021-08-12 13:22:15 +02:00
vt	tty: vt: always invoke vc->vc_sw->con_resize callback	2021-05-26 12:06:56 +02:00
amiserial.c	tty: amiserial: fix TIOCSSERIAL permission check	2021-05-14 09:49:55 +02:00
cyclades.c
ehv_bytechan.c
goldfish.c
isicom.c
Kconfig
Makefile
mips_ejtag_fdc.c
moxa.c	tty: moxa: fix TIOCSSERIAL permission check	2021-05-14 09:49:56 +02:00
moxa.h
mxser.c
mxser.h
n_gsm.c	tty: n_gsm: check error while registering tty devices	2021-05-11 14:47:21 +02:00
n_hdlc.c	tty: convert tty_ldisc_ops 'read()' function to take a kernel pointer	2021-03-04 11:37:36 +01:00
n_null.c	tty: convert tty_ldisc_ops 'read()' function to take a kernel pointer	2021-03-04 11:37:36 +01:00
n_r3964.c	tty: convert tty_ldisc_ops 'read()' function to take a kernel pointer	2021-03-04 11:37:36 +01:00
n_tracerouter.c	tty: convert tty_ldisc_ops 'read()' function to take a kernel pointer	2021-03-04 11:37:36 +01:00
n_tracesink.c	tty: convert tty_ldisc_ops 'read()' function to take a kernel pointer	2021-03-04 11:37:36 +01:00
n_tracesink.h
n_tty.c	tty: teach the n_tty ICANON case about the new "cookie continuations" too	2021-03-07 12:34:16 +01:00
nozomi.c	tty: nozomi: Fix the error handling path of 'nozomi_card_init()'	2021-07-14 16:56:39 +02:00
pty.c
rocket_int.h
rocket.c
rocket.h
synclink_gt.c
synclink.c
synclinkmp.c
sysrq.c
tty_audit.c
tty_baudrate.c
tty_buffer.c
tty_io.c	tty: fix return value for unsupported ioctls	2021-05-14 09:50:18 +02:00
tty_ioctl.c	tty: fix return value for unsupported termiox ioctls	2021-05-14 09:50:19 +02:00
tty_jobctrl.c
tty_ldisc.c
tty_ldsem.c
tty_mutex.c
tty_port.c
ttynull.c
vcc.c