kernel/linux.git/include/linux/serial_core.h, branch v6.6.132

serial: core: introduce uart_port_tx_limited_flags()

2024-07-05T07:34:00+00:00

commit 9bb43b9e8d9a288a214e9b17acc9e46fda3977cf upstream. Analogue to uart_port_tx_flags() introduced in commit 3ee07964d407 ("serial: core: introduce uart_port_tx_flags()"), add a _flags variant for uart_port_tx_limited(). Fixes: d11cc8c3c4b6 ("tty: serial: use uart_port_tx_limited()") Cc: stable@vger.kernel.org Signed-off-by: Jonas Gorski Signed-off-by: Doug Brown Link: https://lore.kernel.org/r/20240606195632.173255-3-doug@schmorgal.com Signed-off-by: Greg Kroah-Hartman

Revert "serial: core: only stop transmit when HW fifo is empty"

2024-07-05T07:33:59+00:00

commit c5603e2a621dac10c5e21cc430848ebcfa6c7e01 upstream. This reverts commit 7bfb915a597a301abb892f620fe5c283a9fdbd77. This commit broke pxa and omap-serial, because it inhibited them from calling stop_tx() if their TX FIFOs weren't completely empty. This resulted in these two drivers hanging during transmits because the TX interrupt would stay enabled, and a new TX interrupt would never fire. Cc: stable@vger.kernel.org Fixes: 7bfb915a597a ("serial: core: only stop transmit when HW fifo is empty") Signed-off-by: Doug Brown Link: https://lore.kernel.org/r/20240606195632.173255-2-doug@schmorgal.com Signed-off-by: Greg Kroah-Hartman

serial: port: Introduce a common helper to read properties

2024-06-21T12:38:49+00:00

[ Upstream commit e894b6005dce0ed621b2788d6a249708fb6f95f9 ] Several serial drivers want to read the same or similar set of the port properties. Make a common helper for them. Signed-off-by: Andy Shevchenko Link: https://lore.kernel.org/r/20240304123035.758700-4-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman Stable-dep-of: 87d80bfbd577 ("serial: 8250_dw: Don't use struct dw8250_data outside of 8250_dw") Signed-off-by: Sasha Levin

serial: core: Add UPIO_UNKNOWN constant for unknown port type

2024-06-21T12:38:49+00:00

[ Upstream commit 79d713baf63c8f23cc58b304c40be33d64a12aaf ] In some APIs we would like to assign the special value to iotype and compare against it in another places. Introduce UPIO_UNKNOWN for this purpose. Note, we can't use 0, because it's a valid value for IO port access. Signed-off-by: Andy Shevchenko Link: https://lore.kernel.org/r/20240304123035.758700-3-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman Stable-dep-of: 87d80bfbd577 ("serial: 8250_dw: Don't use struct dw8250_data outside of 8250_dw") Signed-off-by: Sasha Levin

serial: core: only stop transmit when HW fifo is empty

2024-04-03T13:28:25+00:00

[ Upstream commit 7bfb915a597a301abb892f620fe5c283a9fdbd77 ] If the circular buffer is empty, it just means we fit all characters to send into the HW fifo, but not that the hardware finished transmitting them. So if we immediately call stop_tx() after that, this may abort any pending characters in the HW fifo, and cause dropped characters on the console. Fix this by only stopping tx when the tx HW fifo is actually empty. Fixes: 8275b48b2780 ("tty: serial: introduce transmit helpers") Cc: stable@vger.kernel.org Signed-off-by: Jonas Gorski Link: https://lore.kernel.org/r/20240303150807.68117-1-jonas.gorski@gmail.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

serial: core: introduce uart_port_tx_flags()

2024-02-23T08:25:10+00:00

commit 3ee07964d407411fd578a3bc998de44fd64d266a upstream. And an enum with a flag: UART_TX_NOSTOP. To NOT call __port->ops->stop_tx() when the circular buffer is empty. mxs-uart needs this (see the next patch). Signed-off-by: "Jiri Slaby (SUSE)" Cc: stable Tested-by: Emil Kronborg Link: https://lore.kernel.org/r/20240201105557.28043-1-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

serial: core: fix kernel-doc for uart_port_unlock_irqrestore()

2024-02-01T00:19:14+00:00

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 Cc: Thomas Gleixner Cc: John Ogness Cc: linux-serial@vger.kernel.org Cc: Greg Kroah-Hartman Cc: Jiri Slaby Reviewed-by: John Ogness Link: https://lore.kernel.org/r/20230927044128.4748-1-rdunlap@infradead.org Signed-off-by: Greg Kroah-Hartman

serial: core: Provide port lock wrappers

2024-02-01T00:19:10+00:00

[ 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 Reviewed-by: Ilpo Järvinen Signed-off-by: John Ogness Link: https://lore.kernel.org/r/20230914183831.587273-2-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman Stable-dep-of: 9915753037eb ("serial: sc16is7xx: fix unconditional activation of THRI interrupt") Signed-off-by: Sasha Levin

Merge commit b320441c04c9 ("Merge tag 'tty-6.5-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty") into tty-next

2023-08-20T12:29:37+00:00

We need the serial-core fixes in here as well. Signed-off-by: Greg Kroah-Hartman

serial: core: Fix serial core port id to not use port->line

2023-08-01T05:48:55+00:00

The serial core port id should be serial core controller specific port instance, which is not always the port->line index. For example, 8250 driver maps a number of legacy ports, and when a hardware specific device driver takes over, we typically have one driver instance for each port. Let's instead add port->port_id to keep track serial ports mapped to each serial core controller instance. Currently this is only a cosmetic issue for the serial core port device names. The issue can be noticed looking at /sys/bus/serial-base/devices for example though. Let's fix the issue to avoid port addressing issues later on. Fixes: 84a9582fd203 ("serial: core: Start managing serial controllers to enable runtime PM") Reviewed-by: Andy Shevchenko Signed-off-by: Tony Lindgren Link: https://lore.kernel.org/r/20230725054216.45696-3-tony@atomide.com Signed-off-by: Greg Kroah-Hartman