kernel/drivers/tty/serial/sprd_serial.c, branch linux-6.9.y

serial: sprd: Convert to platform remove callback returning void

2023-11-23T19:12:34Z

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 Acked-by: Chunyan Zhang Link: https://lore.kernel.org/r/20231110152927.70601-41-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman

serial: sprd: Use port lock wrappers

2023-09-18T09:18:15Z

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/20230914183831.587273-63-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman

serial: sprd: Fix DMA buffer leak issue

2023-07-30T11:53:55Z

Release DMA buffer when _probe() returns failure to avoid memory leak. Fixes: f4487db58eb7 ("serial: sprd: Add DMA mode support") Signed-off-by: Chunyan Zhang Reviewed-by: Baolin Wang Link: https://lore.kernel.org/r/20230725064053.235448-2-chunyan.zhang@unisoc.com Signed-off-by: Greg Kroah-Hartman

serial: sprd: Assign sprd_port after initialized to avoid wrong access

2023-07-30T11:53:55Z

The global pointer 'sprd_port' may not zero when sprd_probe returns failure, that is a risk for sprd_port to be accessed afterward, and may lead to unexpected errors. For example: There are two UART ports, UART1 is used for console and configured in kernel command line, i.e. "console="; The UART1 probe failed and the memory allocated to sprd_port[1] was released, but sprd_port[1] was not set to NULL; In UART2 probe, the same virtual address was allocated to sprd_port[2], and UART2 probe process finally will go into sprd_console_setup() to register UART1 as console since it is configured as preferred console (filled to console_cmdline[]), but the console parameters (sprd_port[1]) belong to UART2. So move the sprd_port[] assignment to where the port already initialized can avoid the above issue. Fixes: b7396a38fb28 ("tty/serial: Add Spreadtrum sc9836-uart driver support") Signed-off-by: Chunyan Zhang Link: https://lore.kernel.org/r/20230725064053.235448-1-chunyan.zhang@unisoc.com Signed-off-by: Greg Kroah-Hartman

serial: sprd: Use devm_platform_get_and_ioremap_resource()

2023-07-25T18:26:07Z

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/20230712062853.11007-10-frank.li@vivo.com Signed-off-by: Greg Kroah-Hartman

serial: drivers: switch ch and flag to u8

2023-07-25T17:21:04Z

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

serial: sprd: Drop of_match_ptr for ID table

2023-03-16T12:02:17Z

The driver can match only via the DT table so the table should be always used and the of_match_ptr does not have any sense (this also allows ACPI matching via PRP0001, even though it is not relevant here). drivers/tty/serial/sprd_serial.c:1242:34: error: ‘serial_ids’ defined but not used [-Werror=unused-const-variable=] Signed-off-by: Krzysztof Kozlowski Reviewed-by: Baolin Wang Link: https://lore.kernel.org/r/20230310222957.315848-2-krzysztof.kozlowski@linaro.org Signed-off-by: Greg Kroah-Hartman

serial: sprd: Use uart_xmit_advance()

2022-11-03T02:35:42Z

Take advantage of the new uart_xmit_advance() helper. Reviewed-by: Baolin Wang Signed-off-by: Ilpo Järvinen Link: https://lore.kernel.org/r/20221019091151.6692-34-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman

tty: serial: use uart_port_tx_limited()

2022-11-03T02:32:40Z

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

serial: Make ->set_termios() old ktermios const

2022-08-30T12:22:35Z

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