linux-toradex.git/drivers/tty/serial/fsl_linflexuart.c, branch v6.7

serial: linflexuart: Use port lock wrappers

2023-09-18T09:18:11+00:00

When a serial port is used for kernel console output, then all
modifications to the UART registers which are done from other contexts,
e.g. getty, termios, are interference points for the kernel console.

So far this has been ignored and the printk output is based on the
principle of hope. The rework of the console infrastructure which aims to
support threaded and atomic consoles, requires to mark sections which
modify the UART registers as unsafe. This allows the atomic write function
to make informed decisions and eventually to restore operational state. It
also allows to prevent the regular UART code from modifying UART registers
while printk output is in progress.

All modifications of UART registers are guarded by the UART port lock,
which provides an obvious synchronization point with the console
infrastructure.

To avoid adding this functionality to all UART drivers, wrap the
spin_[un]lock*() invocations for uart_port::lock into helper functions
which just contain the spin_[un]lock*() invocations for now. In a
subsequent step these helpers will gain the console synchronization
mechanisms.

Converted with coccinelle. No functional change.

Signed-off-by: Thomas Gleixner 
Signed-off-by: John Ogness 
Link: https://lore.kernel.org/r/20230914183831.587273-27-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman

tty: serial: linflexuart: Fix to check return value of platform_get_irq() in linflex_probe()

2023-09-18T09:14:43+00:00

The platform_get_irq might be failed and return a negative result. So
there should have an error handling code.

Fixed this by adding an error handling code.

Signed-off-by: Zhang Shurong 
Link: https://lore.kernel.org/r/tencent_234B0AACD06350E10D7548C2E086A9166305@qq.com
Signed-off-by: Greg Kroah-Hartman

serial: linflexuart: Use devm_platform_get_and_ioremap_resource()

2023-07-25T18:25:52+00:00

Convert platform_get_resource(), devm_ioremap_resource() to a single
call to devm_platform_get_and_ioremap_resource(), as this is exactly
what this function does.

Signed-off-by: Yangtao Li 
Link: https://lore.kernel.org/r/20230712062853.11007-4-frank.li@vivo.com
Signed-off-by: Greg Kroah-Hartman

tty: Explicitly include correct DT includes

2023-07-25T18:19:05+00:00

The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it as merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.

Signed-off-by: Rob Herring 
Acked-by: Uwe Kleine-König  # for imx
Link: https://lore.kernel.org/r/20230724205440.767071-1-robh@kernel.org
Signed-off-by: Greg Kroah-Hartman

serial: linflexuart: Use uart_xmit_advance()

2022-11-03T02:35:41+00:00

Take advantage of the new uart_xmit_advance() helper.

Signed-off-by: Ilpo Järvinen 
Link: https://lore.kernel.org/r/20221019091151.6692-16-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman

serial: Make ->set_termios() old ktermios const

2022-08-30T12:22:35+00:00

There should be no reason to adjust old ktermios which is going to get
discarded anyway.

Reviewed-by: Andy Shevchenko 
Signed-off-by: Ilpo Järvinen 
Link: https://lore.kernel.org/r/20220816115739.10928-7-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman

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