Commit graph

4 commits

Author SHA1 Message Date
Randy Dunlap
e9d0a1277b serial: core: fix kernel-doc for uart_port_unlock_irqrestore()
commit 29bff582b74ed0bdb7e6986482ad9e6799ea4d2f upstream.

Fix the function name to avoid a kernel-doc warning:

include/linux/serial_core.h:666: warning: expecting prototype for uart_port_lock_irqrestore(). Prototype was for uart_port_unlock_irqrestore() instead

Fixes: b0af4bcb4946 ("serial: core: Provide port lock wrappers")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: linux-serial@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20230927044128.4748-1-rdunlap@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-19 11:32:40 +01:00
Thomas Gleixner
4b1d47a0fe serial: core: Provide port lock wrappers
[ Upstream commit b0af4bcb49464c221ad5f95d40f2b1b252ceedcc ]

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.

Provide wrapper functions for spin_[un]lock*(port->lock) invocations so
that the console mechanics can be applied later on at a single place and
does not require to copy the same logic all over the drivers.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20230914183831.587273-2-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 54c4ec5f8c47 ("serial: mxs-auart: add spinlock around changing cts state")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 11:32:38 +01:00
Ilpo Järvinen
5d35a2c14b serial: Add rs485_supported to uart_port
[ Upstream commit 8925c31c1ac2f1e05da988581f2a70a2a8c4d638 ]

Preparing to move serial_rs485 struct sanitization into serial core,
each driver has to provide what fields/flags it supports. This
information is pointed into by rs485_supported.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220606100433.13793-4-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 0c2a5f471ce5 ("serial: 8250_exar: Set missing rs485_supported flag")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-18 12:13:34 +01:00
Gabriel2392
7ed7ee9edf Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00