linux.git/drivers/tty/serial/fsl_linflexuart.c, branch v5.19

serial: make uart_console_write->putchar()'s character an unsigned char

2022-03-03T14:06:31+00:00

Currently, uart_console_write->putchar's second parameter (the
character) is of type int. It makes little sense, provided uart_console_write()
accepts the input string as "const char *s" and passes its content -- the
characters -- to putchar(). So switch the character's type to unsigned
char.

We don't use char as that is signed on some platforms. That would cause
troubles for drivers which (implicitly) cast the char to u16 when
writing to the device. Sign extension would happen in that case and the
value written would be completely different to the provided char. DZ is
an example of such a driver -- on MIPS, it uses u16 for dz_out in
dz_console_putchar().

Note we do the char -> uchar conversion implicitly in
uart_console_write(). Provided we do not change size of the data type,
sign extension does not happen there, so the problem is void.

This makes the types consistent and unified with the rest of the uart
layer, which uses unsigned char in most places already. One exception is
xmit_buf, but that is going to be converted later.

Cc: Paul Cercueil 
Cc: Tobias Klauser 
Cc: Russell King 
Cc: Vineet Gupta 
Cc: Nicolas Ferre 
Cc: Alexandre Belloni 
Cc: Ludovic Desroches 
Cc: Florian Fainelli 
Cc: bcm-kernel-feedback-list@broadcom.com
Cc: Alexander Shiyan 
Cc: Baruch Siach 
Cc: "Maciej W. Rozycki" 
Cc: Paul Walmsley 
Cc: Palmer Dabbelt 
Cc: Albert Ou 
Cc: Shawn Guo 
Cc: Sascha Hauer 
Cc: Pengutronix Kernel Team 
Cc: Fabio Estevam 
Cc: NXP Linux Team 
Cc: Karol Gugala 
Cc: Mateusz Holenko 
Cc: Vladimir Zapolskiy 
Cc: Neil Armstrong 
Cc: Kevin Hilman 
Cc: Jerome Brunet 
Cc: Martin Blumenstingl 
Cc: Taichi Sugaya 
Cc: Takao Orito 
Cc: Liviu Dudau 
Cc: Sudeep Holla 
Cc: Lorenzo Pieralisi 
Cc: "Andreas Färber" 
Cc: Manivannan Sadhasivam 
Cc: Michael Ellerman 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Cc: Andy Gross 
Cc: Bjorn Andersson 
Cc: Krzysztof Kozlowski 
Cc: Orson Zhai 
Cc: Baolin Wang 
Cc: Chunyan Zhang 
Cc: Patrice Chotard 
Cc: Maxime Coquelin 
Cc: Alexandre Torgue 
Cc: "David S. Miller" 
Cc: Peter Korsgaard 
Cc: Michal Simek 
Acked-by: Richard Genoud  [atmel_serial]
Acked-by: Uwe Kleine-König 
Acked-by: Paul Cercueil 
Acked-by: Neil Armstrong  # meson_serial
Signed-off-by: Jiri Slaby 
Link: https://lore.kernel.org/r/20220303080831.21783-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman

serial: fsl_linflexuart: don't call uart_write_wakeup() twice

2022-01-26T13:54:48+00:00

linflex_txint() calls linflex_transmit_buffer() which calls
uart_write_wakeup(). So there is no point to repeat it in
linflex_txint() again -- remove it.

Cc: Stefan-gabriel Mirea 
Signed-off-by: Jiri Slaby 
Link: https://lore.kernel.org/r/20220124071430.14907-10-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman

serial: fsl_linflexuart: deduplicate character sending

2022-01-26T13:54:48+00:00

Introduce a new linflex_put_char() helper to send a character. And use
it on both places this code was duplicated.

Cc: Stefan-gabriel Mirea 
Signed-off-by: Jiri Slaby 
Link: https://lore.kernel.org/r/20220124071430.14907-9-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman

tty: serial: linflexuart: Remove redundant check to simplify the code

2021-08-26T12:51:04+00:00

In the function uart_add_one_port(), it can return zero or non-zero,
so remove redundant check to simplify the code.

Signed-off-by: Zhang Shengju 
Signed-off-by: Tang Bin 
Link: https://lore.kernel.org/r/20210823110754.11232-1-tangbin@cmss.chinamobile.com
Signed-off-by: Greg Kroah-Hartman

tty: serial: linflexuart: Remove unnecessary '|' operation and add error count

2020-11-06T16:12:30+00:00

The '|' operation of status in linflex_rxint is unnecessary,
so it can be removed.

Signed-off-by: Liu Xiang 
Link: https://lore.kernel.org/r/1604065391-3790-1-git-send-email-liuxiang_1999@126.com
Signed-off-by: Greg Kroah-Hartman

tty/serial: Migrate fsl_linflexuart to use has_sysrq

2019-12-18T14:04:48+00:00

The SUPPORT_SYSRQ ifdeffery is not nice as:
- May create misunderstanding about sizeof(struct uart_port) between
  different objects
- Prevents moving functions from serial_core.h
- Reduces readability (well, it's ifdeffery - it's hard to follow)

In order to remove SUPPORT_SYSRQ, has_sysrq variable has been added.
Initialise it in driver's probe and remove ifdeffery.

Signed-off-by: Dmitry Safonov 
Link: https://lore.kernel.org/r/20191213000657.931618-18-dima@arista.com
Signed-off-by: Greg Kroah-Hartman

serial: fsl_linflexuart: Be consistent with the name

2019-10-16T13:11:24+00:00

For consistency reasons, spell the controller name as "LINFlexD" in
comments and documentation.

Signed-off-by: Stefan-Gabriel Mirea 
Link: https://lore.kernel.org/r/1571230107-8493-4-git-send-email-stefan-gabriel.mirea@nxp.com
Signed-off-by: Greg Kroah-Hartman

tty: serial: linflexuart: Fix magic SysRq handling

2019-10-04T13:02:28+00:00

Following an incorrect indentation reported to me by Dan Carpenter, I
noticed that the SysRq lines were inherited from the lpuart driver[1] (note
how the 'continue' is aligned to 'sport->port.sysrq = 0') and we have never
actually tested the SysRq support.

'sport->sysrq = 0' is not necessary neither before nor after 'continue',
because sysrq will already be 0 after uart_handle_sysrq_char() will finish.
Also, since the LINFlexD driver never called uart_handle_break(), sysrq
would have never been set to a nonzero value, so uart_handle_sysrq_char()
was not going to do anything.

Break conditions are detected based on a null data byte along with a
framing error (stop bit sampled to 0).

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/tty/serial/fsl_lpuart.c?h=b3e3bf2ef2c74f5ce5c19510edbbb9bfc1d249c2#n659

Fixes: 09864c1cdf5c ("tty: serial: Add linflexuart driver for S32V234")
Signed-off-by: Stefan-Gabriel Mirea 
Reported-by: kbuild test robot 
Reported-by: Dan Carpenter 
Link: https://lore.kernel.org/r/20190918184439.7465-1-stefan-gabriel.mirea@nxp.com
Signed-off-by: Greg Kroah-Hartman

tty: serial: fix platform_no_drv_owner.cocci warnings

2019-09-04T10:44:11+00:00

drivers/tty/serial/fsl_linflexuart.c:907:3-8: No need to set .owner here. The core will do it.

 Remove .owner field if calls are used which set it automatically

Generated by: scripts/coccinelle/api/platform_no_drv_owner.cocci

Fixes: b953815b819b ("tty: serial: Add linflexuart driver for S32V234")
CC: Stefan-gabriel Mirea 
Signed-off-by: kbuild test robot 
Reviewed-by: Uwe Kleine-König 
Link: https://lore.kernel.org/r/20190825142837.zt3hpa22c7iofg3v@48261080c7f1
Signed-off-by: Greg Kroah-Hartman

serial: fsl_linflexuart: Update compatible string

2019-09-04T10:43:56+00:00

The "fsl,s32-linflexuart" compatible string is too generic. Make it SoC
specific.

Signed-off-by: Stefan-Gabriel Mirea 
Link: https://lore.kernel.org/r/20190823191115.18490-4-stefan-gabriel.mirea@nxp.com
Signed-off-by: Greg Kroah-Hartman