linux/drivers/tty
Loic Poulain 76460fbd84 tty: serial: msm_serial: RX SW/FIFO mode fallback
During db410c stress test and when the system is low on memory,
the UART/console becomes unresponsive and never recover back.
This has been narrowed down to the msm_start_rx_dma which does
not manage error cases correctly (e.g. dma mapping failure),
indeed, when an error happens, dma transfer is simply discarded
and so never completed, leading to unconfigured RX path.

This patch fixes this issue by switching to SW/FIFO mode in case
of DMA issue. This mainly consists in resetting the receiver to
apply RX BAM/DMA disabling change and re-enabling the RX level
and stale interrupts (previously disabled for DMA transfers).

The DMA will be re-enabled once memory is available since the
SW/FIFO read function (msm_handle_rx_dm) retries to start dma
on completion.

Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Link: https://lore.kernel.org/r/1578646684-17379-1-git-send-email-loic.poulain@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-14 14:07:51 +01:00
..
hvc TTY/Serial patches for 5.5-rc1 2019-12-03 14:09:14 -08:00
ipwireless tty: add SPDX identifiers to Kconfig and Makefiles 2019-04-04 18:48:43 +02:00
serdev Merge 5.5-rc6 into tty-next 2020-01-13 12:13:05 +01:00
serial tty: serial: msm_serial: RX SW/FIFO mode fallback 2020-01-14 14:07:51 +01:00
vt tty: vt: move conmakehash to drivers/tty/vt/ from scripts/ 2019-12-17 14:42:46 +01:00
amiserial.c Remove every trace of SERIAL_MAGIC 2019-11-13 19:01:14 +08:00
cyclades.c
ehv_bytechan.c
goldfish.c
isicom.c tty/isicom: remove redundant assignment to variable word_count 2019-09-04 12:43:44 +02:00
Kconfig tty: Fix Kconfig indentation, continued 2019-11-21 14:38:31 +01:00
Makefile tty: Add NULL TTY driver 2019-04-16 15:21:34 +02:00
mips_ejtag_fdc.c
moxa.c
moxa.h
mxser.c
mxser.h
n_gsm.c Revert "tty:n_gsm.c: destroy port by tty_port_destroy()" 2019-11-04 17:48:16 +01:00
n_hdlc.c tty: n_hdlc: fix build on SPARC 2019-10-04 15:14:20 +02:00
n_null.c
n_r3964.c tty: Don't block on IO when ldisc change is pending 2018-12-05 12:16:33 +01:00
n_tracerouter.c
n_tracesink.c
n_tracesink.h
n_tty.c n_tty: check for negative and zero space return from tty_write_room 2019-04-16 15:21:33 +02:00
nozomi.c tty: nozomi: Use dev_get_drvdata 2019-09-04 12:43:44 +02:00
pty.c Revert "tty: pty: Fix race condition between release_one_tty and pty_write" 2019-03-29 15:47:40 +01:00
rocket_int.h
rocket.c tty: rocket: reduce stack usage 2019-11-04 17:42:28 +01:00
rocket.h tty: rocket: Remove RCPK_GET_STRUCT ioctl 2019-04-25 11:58:56 +02:00
synclink_gt.c
synclink.c tty/synclink: remove ISA support 2019-02-12 08:51:33 +01:00
synclinkmp.c
sysrq.c sysrq: Remove sysrq_handler_registered 2019-12-17 14:46:23 +01:00
tty_audit.c audit: join tty records to their syscall 2019-02-07 21:33:54 -05:00
tty_baudrate.c termios, tty/tty_baudrate.c: fix buffer overrun 2018-11-08 03:36:45 -08:00
tty_buffer.c tty: increase the default flip buffer limit to 2*640K 2019-01-30 12:03:58 +01:00
tty_io.c tty: drop useless variable initialisation in tty_kopen() 2019-12-17 14:42:45 +01:00
tty_ioctl.c
tty_jobctrl.c tty: fix read of tty->pgrp outside of ctrl_lock 2019-03-28 01:28:23 +09:00
tty_ldisc.c tty_ldisc: simplify tty_ldisc_autoload initialization 2019-10-04 15:11:25 +02:00
tty_ldsem.c locking/lockdep: Remove unused @nested argument from lock_release() 2019-10-09 12:46:10 +02:00
tty_mutex.c
tty_port.c tty: always relink the port 2019-12-30 19:34:44 +01:00
ttynull.c tty: Add NULL TTY driver 2019-04-16 15:21:34 +02:00
vcc.c tty: fix up a few remaining files without SPDX identifiers 2019-04-04 18:48:43 +02:00