kernel/linux.git/drivers/tty/serial/sifive.c, branch v6.7

serial: sifive: Use port lock wrappers

2023-09-18T09:18:15+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/20230914183831.587273-62-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman

serial: sifive: Add suspend and resume operations

2023-08-22T13:29:10+00:00

If the Sifive Uart is not used as the wake up source, suspend the uart before the system enter the suspend state to prevent it woken up by unexpected uart interrupt. Resume the uart once the system woken up. Signed-off-by: Nick Hu Reviewed-by: Ben Dooks Link: https://lore.kernel.org/r/20230815090216.2575971-1-nick.hu@sifive.com Signed-off-by: Greg Kroah-Hartman

serial: sifive: Remove redundant of_match_ptr()

2023-08-09T12:15:25+00:00

The driver depends on CONFIG_OF, it is not necessary to use of_match_ptr() here. Signed-off-by: Ruan Jinjie Link: https://lore.kernel.org/r/20230809085541.2969654-1-ruanjinjie@huawei.com Signed-off-by: Greg Kroah-Hartman

Merge 6.5-rc4 into tty-next

2023-07-31T07:39:56+00:00

We need the serial/tty fixes in here as well for testing and future development. Signed-off-by: Greg Kroah-Hartman

serial: sifive: Fix sifive_serial_console_setup() section

2023-07-25T18:30:02+00:00

This function is called indirectly from the platform driver probe function. Even if the driver is built in, it may be probed after free_initmem() due to deferral or unbinding/binding via sysfs. Thus the function cannot be marked as __init. Fixes: 45c054d0815b ("tty: serial: add driver for the SiFive UART") Cc: stable Signed-off-by: Samuel Holland Link: https://lore.kernel.org/r/20230624060159.3401369-1-samuel.holland@sifive.com Signed-off-by: Greg Kroah-Hartman

serial: sifive: Use devm_platform_get_and_ioremap_resource()

2023-07-25T18:26:07+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/20230712062853.11007-13-frank.li@vivo.com Signed-off-by: Greg Kroah-Hartman

serial: drivers: switch ch and flag to u8

2023-07-25T17:21:04+00:00

Now that the serial layer explicitly expects 'u8' for flags and characters, propagate this type to drivers' (RX) routines. Note that amba-pl011's, clps711x's and st-asc's 'ch' are left unchanged because 'ch' contains not only a character, but whole status. Signed-off-by: Jiri Slaby (SUSE) Cc: Tobias Klauser Cc: Russell King Cc: Vineet Gupta Cc: Richard Genoud Cc: Nicolas Ferre Cc: Alexandre Belloni Cc: Claudiu Beznea Cc: Alexander Shiyan Cc: Baruch Siach Cc: "Maciej W. Rozycki" Cc: Taichi Sugaya Cc: Takao Orito Cc: Shawn Guo Cc: Sascha Hauer Cc: Pengutronix Kernel Team Cc: Fabio Estevam Cc: NXP Linux Team Cc: Kevin Cernekee Cc: Krzysztof Kozlowski Cc: Alim Akhtar Cc: Laxman Dewangan Cc: Thierry Reding Cc: Jonathan Hunter Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Orson Zhai Cc: Baolin Wang Cc: Chunyan Zhang Cc: Patrice Chotard Cc: Maxime Coquelin Cc: Alexandre Torgue Cc: Hammer Hsieh Acked-by: Richard GENOUD Acked-by: Tobias Klauser Acked-by: Thierry Reding Acked-by: Maciej W. Rozycki Link: https://lore.kernel.org/r/20230712081811.29004-11-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

tty: serial: use uart_port_tx_limited()

2022-11-03T02:32:40+00:00

uart_port_tx_limited() is a new helper to send characters to the device. Use it in these drivers. mux.c also needs to define tx_done(). But I'm not sure if the driver really wants to wait for all the characters to dismiss from the HW fifo at this code point. Hence I marked this as FIXME. Cc: Russell King Cc: Florian Fainelli Cc: bcm-kernel-feedback-list@broadcom.com Cc: "Pali Rohár" Cc: Kevin Cernekee Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Orson Zhai Cc: Baolin Wang Cc: Chunyan Zhang Cc: Patrice Chotard Cc: linux-riscv@lists.infradead.org Reviewed-by: Ilpo Järvinen Signed-off-by: Jiri Slaby (SUSE) Link: https://lore.kernel.org/r/20221004104927.14361-4-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

Merge 7e2cd21e02b3 ("Merge tag 'tty-6.0-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty") into tty-next

2022-09-25T07:22:13+00:00

We need the tty fixes and api additions in this branch. Signed-off-by: Greg Kroah-Hartman

serial: sifive: enable clocks for UART when probed

2022-09-22T14:38:18+00:00

When the PWM driver was changed to disable clocks if no PWMs are enabled, it ended up also disabling the shared parent with the UART, since the UART doesn't do any clock enablement on its own. To avoid these surprises, switch to clk_get_enabled(). Fixes: ace41d7564e655 ("pwm: sifive: Ensure the clk is enabled exactly once per running PWM") Cc: stable Cc: Uwe Kleine-König Cc: Emil Renner Berthing Cc: Palmer Dabbelt Cc: Paul Walmsley Reviewed-by: Palmer Dabbelt Reviewed-by: Uwe Kleine-König Acked-by: Palmer Dabbelt Signed-off-by: Olof Johansson Link: https://lore.kernel.org/r/20220920160017.7315-1-olof@lixom.net Signed-off-by: Greg Kroah-Hartman