linux/drivers/tty
Vignesh Raghavendra f19c3f6c81 serial: 8250_port: Don't service RX FIFO if throttled
When port's throttle callback is called, it should stop pushing any more
data into TTY buffer to avoid buffer overflow. This means driver has to
stop HW from receiving more data and assert the HW flow control. For
UARTs with auto HW flow control (such as 8250_omap) manual assertion of
flow control line is not possible and only way is to allow RX FIFO to
fill up, thus trigger auto HW flow control logic.

Therefore make sure that 8250 generic IRQ handler does not drain data
when port is stopped (i.e UART_LSR_DR is unset in read_status_mask). Not
servicing, RX FIFO would trigger auto HW flow control when FIFO
occupancy reaches preset threshold, thus halting RX.
Since, error conditions in UART_LSR register are cleared just by reading
the register, data has to be drained in case there are FIFO errors, else
error information will lost.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200319103230.16867-2-vigneshr@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:25:09 +01:00
..
hvc tty: hvc: Use the correct style for SPDX License Identifier 2020-03-18 13:01:05 +01:00
ipwireless
serdev serdev: Fix detection of UART devices on Apple machines. 2020-03-06 14:10:44 +01:00
serial serial: 8250_port: Don't service RX FIFO if throttled 2020-03-24 12:25:09 +01:00
vt vt: indent switch-case in setterm_command properly 2020-03-16 08:41:17 +01:00
amiserial.c Remove every trace of SERIAL_MAGIC 2019-11-13 19:01:14 +08:00
cyclades.c remove ioremap_nocache and devm_ioremap_nocache 2020-01-06 09:45:59 +01:00
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 tty: mips_ejtag_fdc: Mark expected switch fall-through 2020-03-07 09:52:02 +01:00
moxa.c remove ioremap_nocache and devm_ioremap_nocache 2020-01-06 09:45:59 +01:00
moxa.h
mxser.c
mxser.h
n_gsm.c n_gsm: switch escape to bool 2020-02-19 12:46:48 +01:00
n_hdlc.c tty: n_hdlc, remove FILE and LINE from pr_debug 2020-03-16 08:39:47 +01:00
n_null.c
n_r3964.c
n_tracerouter.c
n_tracesink.c
n_tracesink.h tty: n_tracesink: Use the correct style for SPDX License Identifier 2020-03-18 13:01:31 +01:00
n_tty.c n_tty: Distribute switch variables for initialization 2020-02-23 20:14:50 +01:00
nozomi.c tty: nozomi: Use scnprintf() for avoiding potential buffer overflow 2020-03-18 12:59:29 +01:00
pty.c
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 TTY/Serial driver updates for 5.6-rc1 2020-01-29 10:13:27 -08:00
synclink.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 2020-01-28 16:02:33 -08:00
synclinkmp.c TTY/Serial driver updates for 5.6-rc1 2020-01-29 10:13:27 -08:00
sysrq.c sysctl/sysrq: Remove __sysrq_enabled copy 2020-03-07 09:52:02 +01:00
tty_audit.c
tty_baudrate.c tty: baudrate: SPARC supports few more baud rates 2020-01-22 10:23:26 +01:00
tty_buffer.c
tty_io.c tty: fix compat TIOCGSERIAL checking wrong function ptr 2020-03-18 13:15:13 +01:00
tty_ioctl.c
tty_jobctrl.c
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 serdev: ttyport: restore client ops on deregistration 2020-02-10 12:26:44 -08:00
ttynull.c tty: Add NULL TTY driver 2019-04-16 15:21:34 +02:00
vcc.c