linux.git/drivers/tty/serial/liteuart.c, branch v6.12.80 Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git serial: liteuart: Convert to platform remove callback returning void 2023-11-23T19:12:32+00:00 Uwe Kleine-König u.kleine-koenig@pengutronix.de 2023-11-10T15:29:47+00:00 2d1c01d4cf26710920c37468ed49d6c41e11944c The .remove() callback for a platform driver returns an int which makes many driver authors wrongly assume it's possible to do error handling by returning an error code. However the value returned is ignored (apart from emitting a warning) and this typically results in resource leaks. To improve here there is a quest to make the remove callback return void. In the first step of this quest all drivers are converted to .remove_new(), which already returns void. Eventually after all drivers are converted, .remove_new() will be renamed to .remove(). Trivially convert this driver from always returning zero in the remove callback to the void returning variant. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Gabriel Somlo <gsomlo@gmail.com> Link: https://lore.kernel.org/r/20231110152927.70601-20-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Gabriel Somlo <gsomlo@gmail.com>
Link: https://lore.kernel.org/r/20231110152927.70601-20-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: liteuart: Use port lock wrappers 2023-09-18T09:18:11+00:00 Thomas Gleixner tglx@linutronix.de 2023-09-14T18:37:49+00:00 12e675503dbef7ed860187bc15d34965a0fd663f 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 <tglx@linutronix.de> Acked-by: Gabriel Somlo <gsomlo@gmail.com> Signed-off-by: John Ogness <john.ogness@linutronix.de> Link: https://lore.kernel.org/r/20230914183831.587273-33-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
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 <tglx@linutronix.de>
Acked-by: Gabriel Somlo <gsomlo@gmail.com>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20230914183831.587273-33-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty: Explicitly include correct DT includes 2023-07-25T18:19:05+00:00 Rob Herring robh@kernel.org 2023-07-24T20:54:38+00:00 29e5c442e553cea180682d54ac0e2e95250fa668 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 <robh@kernel.org> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> # for imx Link: https://lore.kernel.org/r/20230724205440.767071-1-robh@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
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 <robh@kernel.org>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> # for imx
Link: https://lore.kernel.org/r/20230724205440.767071-1-robh@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: liteuart: Remove a copy of UART id in private structure 2023-01-31T09:59:48+00:00 Andy Shevchenko andriy.shevchenko@linux.intel.com 2023-01-23T19:26:04+00:00 646b4cd9909aaf2bfb9e05897e9c3871a7385219 The struct liteuart_port keeps tracking of UART ID which is also saved in the struct uart_port as line member. Drop the former one and use the latter everywhere. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Gabriel Somlo <gsomlo@gmail.com> Link: https://lore.kernel.org/r/20230123192604.81452-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
The struct liteuart_port keeps tracking of UART ID which is also
saved in the struct uart_port as line member. Drop the former one
and use the latter everywhere.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Gabriel Somlo <gsomlo@gmail.com>
Link: https://lore.kernel.org/r/20230123192604.81452-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: liteuart: Don't mix devm_*() with non-devm_*() calls 2023-01-31T09:59:40+00:00 Andy Shevchenko andriy.shevchenko@linux.intel.com 2023-01-23T19:17:41+00:00 297cb3f0b94bfedd781426814f1798a5c5658050 In the probe we need to call all devm_*() first followed by non-devm_*() calls. This is due to reversed clean up that may happen in a wrong order otherwise. The driver currently allocates xarray before calling devm_platform_get_and_ioremap_resource(). While it's not an issue in this certain case, it's still better to be pedantic. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Gabriel Somlo <somlo@cmu.edu> Link: https://lore.kernel.org/r/20230123191741.79751-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
In the probe we need to call all devm_*() first followed by
non-devm_*() calls. This is due to reversed clean up that
may happen in a wrong order otherwise. The driver currently
allocates xarray before calling
devm_platform_get_and_ioremap_resource(). While it's not an
issue in this certain case, it's still better to be pedantic.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Gabriel Somlo <somlo@cmu.edu>
Link: https://lore.kernel.org/r/20230123191741.79751-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: liteuart: Correct error rollback 2023-01-23T17:51:58+00:00 Ilpo Järvinen ilpo.jarvinen@linux.intel.com 2023-01-23T17:38:57+00:00 ed0400ad547c0b88d2f06ecf22a089eb2e84c9b7 Goto to the correct rollback label instead of directly returning. Fixes: 5602cf99dcdc ("serial: liteuart: add IRQ support for the RX path") Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Reported-by: kernel test robot <lkp@intel.com> Reported-by: Dan Carpenter <error27@gmail.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Reviewed-by: Gabriel Somlo <gsomlo@gmail.com> Link: https://lore.kernel.org/r/20230123173857.40695-3-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Goto to the correct rollback label instead of directly returning.

Fixes: 5602cf99dcdc ("serial: liteuart: add IRQ support for the RX path")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Gabriel Somlo <gsomlo@gmail.com>
Link: https://lore.kernel.org/r/20230123173857.40695-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: liteuart: move polling putchar() function 2023-01-19T13:59:41+00:00 Gabriel Somlo gsomlo@gmail.com 2022-11-23T13:05:00+00:00 f1c6c8b1b42dd72bd54adec003463650b84893d8 The polling liteuart_putchar() function is only called from methods conditionally enabled by CONFIG_SERIAL_LITEUART_CONSOLE. Move its definition closer to the console code where it is dependent on the same config option. Signed-off-by: Gabriel Somlo <gsomlo@gmail.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20221123130500.1030189-15-gsomlo@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
The polling liteuart_putchar() function is only called from methods
conditionally enabled by CONFIG_SERIAL_LITEUART_CONSOLE. Move its
definition closer to the console code where it is dependent on the
same config option.

Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20221123130500.1030189-15-gsomlo@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: liteuart: add IRQ support for the TX path 2023-01-19T13:59:41+00:00 Gabriel Somlo gsomlo@gmail.com 2022-11-23T13:04:59+00:00 01a305a36639a438e27503202a46f191b74bd168 Switch the TX path to IRQ-driven operation, while maintaining support for polling mode via the poll timer. Signed-off-by: Gabriel Somlo <gsomlo@gmail.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20221123130500.1030189-14-gsomlo@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Switch the TX path to IRQ-driven operation, while maintaining support
for polling mode via the poll timer.

Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20221123130500.1030189-14-gsomlo@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: liteuart: add IRQ support for the RX path 2023-01-19T13:59:40+00:00 Gabriel Somlo gsomlo@gmail.com 2022-11-23T13:04:58+00:00 5602cf99dcdcc0bf8f9a5979b7443fbe46686995 Add support for IRQ-driven RX. Support for the TX path will be added in a separate commit. Signed-off-by: Gabriel Somlo <gsomlo@gmail.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20221123130500.1030189-13-gsomlo@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Add support for IRQ-driven RX. Support for the TX path will be added
in a separate commit.

Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20221123130500.1030189-13-gsomlo@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: liteuart: move function definitions 2023-01-19T13:59:40+00:00 Gabriel Somlo gsomlo@gmail.com 2022-11-23T13:04:57+00:00 7121d86effddc28dc21fec38d59923ea12d5a873 Move definitions for liteuart_[stop|start]_tx(), liteuart_stop_rx(), and liteuart_putchar() to a more convenient location in preparation for adding IRQ support. This patch contains no functional changes. Signed-off-by: Gabriel Somlo <gsomlo@gmail.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20221123130500.1030189-12-gsomlo@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Move definitions for liteuart_[stop|start]_tx(), liteuart_stop_rx(),
and liteuart_putchar() to a more convenient location in preparation
for adding IRQ support. This patch contains no functional changes.

Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20221123130500.1030189-12-gsomlo@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>