linux/drivers/tty
Lino Sanfilippo 0e4deb56b0 serial: amba-pl011: do not time out prematurely when draining tx fifo
The current timeout for draining the tx fifo in RS485 mode is calculated by
multiplying the time it takes to transmit one character (with the given
baud rate) with the maximal number of characters in the tx queue.

This timeout is too short for two reasons:
First when calculating the time to transmit one character integer division
is used which may round down the result in case of a remainder of the
division.

Fix this by rounding up the division result.

Second the hardware may need additional time (e.g for first putting the
characters from the fifo into the shift register) before the characters are
actually put onto the wire.

To be on the safe side double the current maximum number of iterations
that are used to wait for the queue draining.

Fixes: 8d47923772 ("serial: amba-pl011: add RS485 support")
Cc: stable@vger.kernel.org
Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220408233503.7251-1-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 11:41:56 +02:00
..
hvc tty: hvc: fix return value of __setup handler 2022-03-18 13:09:57 +01:00
ipwireless tty: drop put_tty_driver 2021-07-27 12:17:21 +02:00
serdev tty: Replace acpi_bus_get_device() 2022-01-31 14:30:06 +01:00
serial serial: amba-pl011: do not time out prematurely when draining tx fifo 2022-04-15 11:41:56 +02:00
vt vt_ioctl: fix potential spectre v1 in VT_DISALLOCATE 2022-03-18 14:35:01 +01:00
amiserial.c amiserial: Drop duplicate NULL check in shutdown() 2022-02-04 15:42:53 +01:00
ehv_bytechan.c tty: drop put_tty_driver 2021-07-27 12:17:21 +02:00
goldfish.c serial: make uart_console_write->putchar()'s character an unsigned char 2022-03-03 15:06:31 +01:00
Kconfig tty: add rpmsg driver 2021-10-21 12:35:35 +02:00
Makefile tty: add rpmsg driver 2021-10-21 12:35:35 +02:00
mips_ejtag_fdc.c tty: mips_ejtag_fdc: Make use of the helper function kthread_run_on_cpu() 2021-12-03 16:00:41 +01:00
moxa.c tty: drivers/tty/, stop using tty_schedule_flip() 2021-11-25 18:35:23 +01:00
mxser.c mxser: make use of UART_LCR_WLEN() + tty_get_char_size() 2022-02-28 22:17:25 +01:00
n_gsm.c tty: n_gsm: fix incorrect UA handling 2022-04-15 08:36:05 +02:00
n_hdlc.c Linux 5.16-rc6 2021-12-20 10:00:30 +01:00
n_null.c
n_tty.c tty: n_tty: do not look ahead for EOL character past the end of the buffer 2022-02-16 10:13:23 -08:00
nozomi.c tty: drop put_tty_driver 2021-07-27 12:17:21 +02:00
pty.c
rpmsg_tty.c tty: rpmsg: Fix race condition releasing tty port 2022-01-26 14:50:26 +01:00
synclink_gt.c tty: synclink_gt: rename a conflicting function name 2021-09-14 10:51:37 +02:00
sysrq.c TTY / Serial driver update for 5.16-rc1 2021-11-04 09:09:37 -07:00
tty_audit.c
tty_baudrate.c tty: baudrate: Explicit usage of B0 for encoding input baudrate 2021-10-05 15:00:56 +02:00
tty_buffer.c tty: reformat kernel-doc in tty_buffer.c 2021-11-26 16:27:43 +01:00
tty_io.c memcg: enable accounting for tty-related objects 2022-03-22 15:57:04 -07:00
tty_ioctl.c tty: remove file from n_tty_ioctl_helper 2021-09-22 16:59:13 +02:00
tty_jobctrl.c
tty_ldisc.c tty: reformat kernel-doc in tty_ldisc.c 2021-11-26 16:27:43 +01:00
tty_ldsem.c tty/ldsem: Fix syntax errors in comments 2021-12-21 09:15:49 +01:00
tty_mutex.c
tty_port.c tty: Drop duplicate NULL check in TTY port functions 2022-02-04 16:58:25 +01:00
tty.h
ttynull.c tty: drop put_tty_driver 2021-07-27 12:17:21 +02:00
vcc.c tty: drop put_tty_driver 2021-07-27 12:17:21 +02:00