linux/drivers/tty
Vignesh R 08fb00c64f serial: 8250: 8250_omap: Fix throttling when DMA is enabled
omap_8250_throttle() is called when tty RX buffer is about to overflow
and can no longer keep up with the rate at which UART is receiving data.
So, the expectation of this callback, is that UART stops RX and asserts
HW flow control to signal the sender to stop sending more data.
omap_8250_throttle() disables RX FIFO interrupts thus FIFO is no longer
serviced, leading to assertion of flow control once RX FIFO is full.
But, this does not work when DMA is enabled as driver keeps queuing new
RX DMA request in completion handler without brothering about throttling
request made by the higher layer.
This patch introduces a flag that can be used to determine whether or
not to queue next RX DMA request based on throttling request.

Without this patch, tty buffer overflows are reported at higher
baudrates.

Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 13:40:22 +01:00
..
hvc TTY/Serial patches for 4.15-rc1 2017-11-13 21:05:31 -08:00
ipwireless treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
serdev TTY/Staging driver updates for 4.16-rc1 2018-02-01 09:46:00 -08:00
serial serial: 8250: 8250_omap: Fix throttling when DMA is enabled 2018-02-28 13:40:22 +01:00
vt vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
amiserial.c tty: add SPDX identifiers to all remaining files in drivers/tty/ 2017-11-08 13:08:12 +01:00
bfin_jtag_comm.c tty: Remove redundant license text 2017-11-08 13:08:12 +01:00
cyclades.c treewide: Switch DEFINE_TIMER callbacks to struct timer_list * 2017-11-21 15:57:05 -08:00
ehv_bytechan.c tty: ehv_bytechan: fix spelling mistake 2017-11-08 14:27:10 +01:00
goldfish.c tty: goldfish: Enable 'earlycon' only if built-in 2017-12-15 20:27:44 +01:00
isicom.c tty/isicom: Fix a possible sleep-in-atomic bug in WaitTillCardIsFree 2017-12-15 20:24:14 +01:00
Kconfig tty: goldfish: Enable 'earlycon' only if built-in 2017-12-15 20:27:44 +01:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
metag_da.c tty: Remove redundant license text 2017-11-08 13:08:12 +01:00
mips_ejtag_fdc.c tty: Remove redundant license text 2017-11-08 13:08:12 +01:00
moxa.c tty: moxa: Add support for CMSPAR 2017-11-28 15:32:33 +01:00
moxa.h tty: moxa: Add support for CMSPAR 2017-11-28 15:32:33 +01:00
mxser.c tty: Remove redundant license text 2017-11-08 13:08:12 +01:00
mxser.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
n_gsm.c vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
n_hdlc.c vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
n_null.c tty: Remove redundant license text 2017-11-08 13:08:12 +01:00
n_r3964.c vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
n_tracerouter.c tty: Remove redundant license text 2017-11-08 13:08:12 +01:00
n_tracesink.c tty: Remove redundant license text 2017-11-08 13:08:12 +01:00
n_tracesink.h tty: Remove redundant license text 2017-11-08 13:08:12 +01:00
n_tty.c vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
nozomi.c tty: Remove redundant license text 2017-11-08 13:08:12 +01:00
pty.c vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
rocket_int.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
rocket.c treewide: Switch DEFINE_TIMER callbacks to struct timer_list * 2017-11-21 15:57:05 -08:00
rocket.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
synclink_gt.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
synclink.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
synclinkmp.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
sysrq.c TTY/Serial patches for 4.15-rc1 2017-11-13 21:05:31 -08:00
tty_audit.c tty: Remove redundant license text 2017-11-08 13:08:12 +01:00
tty_baudrate.c tty: add SPDX identifiers to all remaining files in drivers/tty/ 2017-11-08 13:08:12 +01:00
tty_buffer.c tty: add SPDX identifiers to all remaining files in drivers/tty/ 2017-11-08 13:08:12 +01:00
tty_io.c vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
tty_ioctl.c tty: add SPDX identifiers to all remaining files in drivers/tty/ 2017-11-08 13:08:12 +01:00
tty_jobctrl.c tty: add SPDX identifiers to all remaining files in drivers/tty/ 2017-11-08 13:08:12 +01:00
tty_ldisc.c vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
tty_ldsem.c tty: Remove redundant license text 2017-11-08 13:08:12 +01:00
tty_mutex.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
tty_port.c tty: add SPDX identifiers to all remaining files in drivers/tty/ 2017-11-08 13:08:12 +01:00
vcc.c tty: vcc: Convert timers to use timer_setup() 2017-11-04 12:01:54 +01:00