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

tty: serial: uartps: Add rs485 support to uartps driver

2024-01-28T03:07:08Z

Add rs485 support to uartps driver. Use either rts-gpios or RTS to control RS485 phy as driver or a receiver. Signed-off-by: Manikanta Guntupalli Link: https://lore.kernel.org/r/20240123061655.2150946-4-manikanta.guntupalli@amd.com Signed-off-by: Greg Kroah-Hartman

tty: serial: uartps: Relocate cdns_uart_tx_empty to facilitate rs485

2024-01-28T03:07:08Z

Relocate cdns_uart_tx_empty function to avoid prototype statement in rs485 changes. Update return check with uart_tx_stopped() in cdns_uart_handle_tx(). Signed-off-by: Manikanta Guntupalli Link: https://lore.kernel.org/r/20240123061655.2150946-3-manikanta.guntupalli@amd.com Signed-off-by: Greg Kroah-Hartman

serial: xilinx_uartps: Fix kernel doc about .remove()'s return code

2023-11-25T07:23:16Z

Since the driver was converted to use .remove_new() the return function doesn't return a value any more. So remove the obsolete documentation about the return value. Reported-by: Michal Simek Signed-off-by: Uwe Kleine-König Acked-by: Michal Simek Link: https://lore.kernel.org/r/20231117101236.878008-1-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman

serial: xilinx_uartps: Convert to platform remove callback returning void

2023-11-23T19:12:36Z

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 Link: https://lore.kernel.org/r/20231110152927.70601-53-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman

serial: xilinx_uartps: unset STOPBRK when setting STARTBRK

2023-10-16T18:14:42Z

Zynq UG585 states, in chapter B.33, for XUARTPS_CR_STARTBRK: It can only be set if STPBRK (Stop transmitter break) is not high This fixes tcsendbreak, which otherwise does not actually break. Signed-Off-By: Julien Malik Link: https://lore.kernel.org/r/20230624210323.88455-1-julien.malik@unseenlabs.fr Signed-off-by: Greg Kroah-Hartman

serial: xilinx_uartps: Use port lock wrappers

2023-09-18T09:18:16Z

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/20230914183831.587273-75-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman

tty: serial: xilinx_uartps: Do not check for 0 return after calling platform_get_irq()

2023-08-04T13:06:01Z

Since commit a85a6c86c25b ("driver core: platform: Clarify that IRQ 0 is invalid"), there is no possible for platform_get_irq() to return 0. Use the return value from platform_get_irq(). Signed-off-by: Ruan Jinjie Link: https://lore.kernel.org/r/20230803091712.596987-1-ruanjinjie@huawei.com Signed-off-by: Greg Kroah-Hartman

serial: Make uart_remove_one_port() return void

2023-05-13T10:48:16Z

The return value is only ever used as a return value for remove callbacks of platform drivers. This return value is ignored by the driver core. (The only effect is an error message, but uart_remove_one_port() already emitted one in this case.) So the return value isn't used at all and uart_remove_one_port() can be changed to return void without any loss. Also this better matches the Linux device model as remove functions are not supposed to fail. Signed-off-by: Uwe Kleine-König Link: https://lore.kernel.org/r/20230512173810.131447-3-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman

Merge tag 'tty-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

2022-12-16T11:31:56Z

Pull tty/serial driver updates from Greg KH: "Here is the "big" set of tty/serial driver changes for 6.2-rc1. As in previous kernel releases, nothing big here at all, just some small incremental serial/tty layer cleanups and some individual driver additions and fixes. Highlights are: - serial helper macros from Jiri Slaby to reduce the amount of duplicated code in serial drivers - api cleanups and consolidations from Ilpo Järvinen in lots of serial drivers - the usual set of n_gsm fixes from Daniel Starke as that code gets exercised more - TIOCSTI is finally able to be disabled if requested (security hardening feature from Kees Cook) - fsl_lpuart driver fixes and features added - other small serial driver additions and fixes All of these have been in linux-next for a while with no reported problems" * tag 'tty-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (97 commits) serial: atmel: don't stop the transmitter when doing PIO serial: atmel: cleanup atmel_start+stop_tx() tty: serial: fsl_lpuart: switch to new dmaengine_terminate_* API serial: sunsab: Fix error handling in sunsab_init() serial: altera_uart: fix locking in polling mode serial: pch: Fix PCI device refcount leak in pch_request_dma() tty: serial: fsl_lpuart: Use pm_ptr() to avoid need to make pm __maybe_unused tty: serial: fsl_lpuart: Add runtime pm support tty: serial: fsl_lpuart: enable wakeup source for lpuart serdev: Replace poll loop by readx_poll_timeout() macro tty: synclink_gt: unwind actions in error path of net device open serial: stm32: move dma_request_chan() before clk_prepare_enable() dt-bindings: serial: xlnx,opb-uartlite: Drop 'contains' from 'xlnx,use-parity' serial: pl011: Do not clear RX FIFO & RX interrupt in unthrottle. serial: amba-pl011: avoid SBSA UART accessing DMACR register tty: serial: altera_jtaguart: remove struct altera_jtaguart tty: serial: altera_jtaguart: use uart_port::read_status_mask tty: serial: altera_jtaguart: remove unused altera_jtaguart::sigs tty: serial: altera_jtaguart: remove flag from altera_jtaguart_rx_chars() n_tty: Rename tail to old_tail in n_tty_read() ...

tty: serial: xilinx_uartps: use console_is_registered()

2022-12-02T10:25:01Z

It is not reliable to check for CON_ENABLED in order to identify if a console is registered. Use console_is_registered() instead. Signed-off-by: John Ogness Reviewed-by: Petr Mladek Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20221116162152.193147-30-john.ogness@linutronix.de