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2025-02-19serial: mctrl_gpio: split disable_ms into sync and no_sync APIsAlexis Lothoré
The following splat has been observed on a SAMA5D27 platform using atmel_serial: BUG: sleeping function called from invalid context at kernel/irq/manage.c:738 in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 27, name: kworker/u5:0 preempt_count: 1, expected: 0 INFO: lockdep is turned off. irq event stamp: 0 hardirqs last enabled at (0): [<00000000>] 0x0 hardirqs last disabled at (0): [<c01588f0>] copy_process+0x1c4c/0x7bec softirqs last enabled at (0): [<c0158944>] copy_process+0x1ca0/0x7bec softirqs last disabled at (0): [<00000000>] 0x0 CPU: 0 UID: 0 PID: 27 Comm: kworker/u5:0 Not tainted 6.13.0-rc7+ #74 Hardware name: Atmel SAMA5 Workqueue: hci0 hci_power_on [bluetooth] Call trace: unwind_backtrace from show_stack+0x18/0x1c show_stack from dump_stack_lvl+0x44/0x70 dump_stack_lvl from __might_resched+0x38c/0x598 __might_resched from disable_irq+0x1c/0x48 disable_irq from mctrl_gpio_disable_ms+0x74/0xc0 mctrl_gpio_disable_ms from atmel_disable_ms.part.0+0x80/0x1f4 atmel_disable_ms.part.0 from atmel_set_termios+0x764/0x11e8 atmel_set_termios from uart_change_line_settings+0x15c/0x994 uart_change_line_settings from uart_set_termios+0x2b0/0x668 uart_set_termios from tty_set_termios+0x600/0x8ec tty_set_termios from ttyport_set_flow_control+0x188/0x1e0 ttyport_set_flow_control from wilc_setup+0xd0/0x524 [hci_wilc] wilc_setup [hci_wilc] from hci_dev_open_sync+0x330/0x203c [bluetooth] hci_dev_open_sync [bluetooth] from hci_dev_do_open+0x40/0xb0 [bluetooth] hci_dev_do_open [bluetooth] from hci_power_on+0x12c/0x664 [bluetooth] hci_power_on [bluetooth] from process_one_work+0x998/0x1a38 process_one_work from worker_thread+0x6e0/0xfb4 worker_thread from kthread+0x3d4/0x484 kthread from ret_from_fork+0x14/0x28 This warning is emitted when trying to toggle, at the highest level, some flow control (with serdev_device_set_flow_control) in a device driver. At the lowest level, the atmel_serial driver is using serial_mctrl_gpio lib to enable/disable the corresponding IRQs accordingly. The warning emitted by CONFIG_DEBUG_ATOMIC_SLEEP is due to disable_irq (called in mctrl_gpio_disable_ms) being possibly called in some atomic context (some tty drivers perform modem lines configuration in regions protected by port lock). Split mctrl_gpio_disable_ms into two differents APIs, a non-blocking one and a blocking one. Replace mctrl_gpio_disable_ms calls with the relevant version depending on whether the call is protected by some port lock. Suggested-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Alexis Lothoré <alexis.lothore@bootlin.com> Acked-by: Richard Genoud <richard.genoud@bootlin.com> Link: https://lore.kernel.org/r/20250217-atomic_sleep_mctrl_serial_gpio-v3-1-59324b313eef@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-18serial: xilinx_uartps: Use helper function hrtimer_update_function()Nam Cao
The field 'function' of struct hrtimer should not be changed directly, as the write is lockless and a concurrent timer expiry might end up using the wrong function pointer. Switch to use hrtimer_update_function() which also performs runtime checks that it is safe to modify the callback. Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/af7823518fb060c6c97105a2513cfc61adbdf38f.1738746927.git.namcao@linutronix.de
2025-02-18serial: xilinx_uartps: Switch to use hrtimer_setup()Nam Cao
hrtimer_setup() takes the callback function pointer as argument and initializes the timer completely. Replace hrtimer_init() and the open coded initialization of hrtimer::function with the new setup mechanism. Patch was created by using Coccinelle. Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Zack Rusin <zack.rusin@broadcom.com> Link: https://lore.kernel.org/all/4a028a23126b3350a5e243dcb49e1ef1b2a4b740.1738746904.git.namcao@linutronix.de
2025-02-18serial: sh-sci: Switch to use hrtimer_setup()Nam Cao
hrtimer_setup() takes the callback function pointer as argument and initializes the timer completely. Replace hrtimer_init() and the open coded initialization of hrtimer::function with the new setup mechanism. Patch was created by using Coccinelle. Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Zack Rusin <zack.rusin@broadcom.com> Link: https://lore.kernel.org/all/c21664d013015584aebbb6bb8cedd748182cb551.1738746904.git.namcao@linutronix.de
2025-02-18serial: imx: Switch to use hrtimer_setup()Nam Cao
hrtimer_setup() takes the callback function pointer as argument and initializes the timer completely. Replace hrtimer_init() and the open coded initialization of hrtimer::function with the new setup mechanism. Patch was created by using Coccinelle. Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Zack Rusin <zack.rusin@broadcom.com> Link: https://lore.kernel.org/all/ad27070bc67c13f8a9acbd5cbf4cbae72797e3e1.1738746904.git.namcao@linutronix.de
2025-02-18serial: amba-pl011: Switch to use hrtimer_setup()Nam Cao
hrtimer_setup() takes the callback function pointer as argument and initializes the timer completely. Replace hrtimer_init() and the open coded initialization of hrtimer::function with the new setup mechanism. Patch was created by using Coccinelle. Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/78e8c0d1b38998eab983fad265751ed13c2b9009.1738746904.git.namcao@linutronix.de
2025-02-18serial: 8250: Switch to use hrtimer_setup()Nam Cao
hrtimer_setup() takes the callback function pointer as argument and initializes the timer completely. Replace hrtimer_init() and the open coded initialization of hrtimer::function with the new setup mechanism. Patch was created by using Coccinelle. Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Zack Rusin <zack.rusin@broadcom.com> Link: https://lore.kernel.org/all/991926d130cc272df30d226760d5d74187991669.1738746904.git.namcao@linutronix.de
2025-02-17Merge 6.14-rc3 into tty-nextGreg Kroah-Hartman
We need the tty changes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-16Merge tag 'tty-6.14-rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull serial driver fixes from Greg KH: "Here are some small serial driver fixes for some reported problems. Nothing major, just: - sc16is7xx irq check fix - 8250 fifo underflow fix - serial_port and 8250 iotype fixes Most of these have been in linux-next already, and all have passed 0-day testing" * tag 'tty-6.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: serial: 8250: Fix fifo underflow on flush serial: 8250_pnp: Remove unneeded ->iotype assignment serial: 8250_platform: Remove unneeded ->iotype assignment serial: 8250_of: Remove unneeded ->iotype assignment serial: port: Make ->iotype validation global in __uart_read_properties() serial: port: Always update ->iotype in __uart_read_properties() serial: port: Assign ->iotype correctly when ->iobase is set serial: sc16is7xx: Fix IRQ number check behavior
2025-02-14serial: tegra-utc: Add driver for Tegra UART Trace Controller (UTC)Kartik Rajput
The Tegra264 SoC supports the UART Trace Controller (UTC), which allows multiple firmware clients (up to 16) to share a single physical UART. Each client is provided with its own interrupt and has access to a 128-character wide FIFO for both transmit (TX) and receive (RX) operations. Add tegra-utc driver to support Tegra UART Trace Controller (UTC) client. Signed-off-by: Kartik Rajput <kkartik@nvidia.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250213125612.4705-3-kkartik@nvidia.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-14Revert "tty/serial: Add kgdb_nmi driver"Douglas Anderson
This reverts commit 0c57dfcc6c1d037243c2f8fbf62eab3633326ec0. The functionality was supoosed to be used by a later patch in the series that never landed [1]. Drop it. NOTE: part of functionality was already reverted by commit 39d0be87438a ("serial: kgdb_nmi: Remove unused knock code"). Also note that this revert is not a clean revert given code changes that have happened in the meantime. It's obvious that nobody is using this code since the two exposed functions (kgdb_register_nmi_console() and kgdb_unregister_nmi_console()) are both no-ops if "arch_kgdb_ops.enable_nmi" is not defined. No architectures define it. [1] https://lore.kernel.org/lkml/1348522080-32629-9-git-send-email-anton.vorontsov@linaro.org/ Signed-off-by: Douglas Anderson <dianders@chromium.org> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: URL [1] Link: https://lore.kernel.org/r/20250129082535.1.Ia095eac1ae357f87d23e7af2206741f5d40788f1@changeid Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-14serial: 8250_dw: Call dw8250_quirks() conditionallyAndy Shevchenko
Not all the cases provide the driver data, that is represented by an object instance of struct dw8250_platform_data. Id est the change missed the case when the driver is instantiated via board files as pure platform driver. Fix this by calling dw8250_quirks() conditionally. This will require splitting dw8250_setup_dma_filter() out of dw8250_quirks(). Also make sure IRQ handler won't crash, it also requires driver data to be present. Fixes: bfd3d4a40f39 ("serial: 8250_dw: Drop unneeded NULL checks in dw8250_quirks()") Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202502121529.f7e65d49-lkp@intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250212115952.2312444-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-14serial: sh-sci: Update the suspend/resume supportClaudiu Beznea
The Renesas RZ/G3S supports a power saving mode where power to most of the SoC components is turned off. When returning from this power saving mode, SoC components need to be re-configured. The SCIFs on the Renesas RZ/G3S need to be re-configured as well when returning from this power saving mode. The sh-sci code already configures the SCIF clocks, power domain and registers by calling uart_resume_port() in sci_resume(). On suspend path the SCIF UART ports are suspended accordingly (by calling uart_suspend_port() in sci_suspend()). The only missing setting is the reset signal. For this assert/de-assert the reset signal on driver suspend/resume. In case the no_console_suspend is specified by the user, the registers need to be saved on suspend path and restore on resume path. To do this the sci_console_save()/sci_console_restore() functions were added. There is no need to cache/restore the status or FIFO registers. Only the control registers. The registers that will be saved/restored on suspend/resume are specified by the struct sci_suspend_regs data structure. Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/20250207113313.545432-1-claudiu.beznea.uj@bp.renesas.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-14tty: serial: fsl_lpuart: Make interrupt name distinctStefan Wahren
SoCs like the i.MX93 have several lpuart interfaces, but fsl_lpuart uses the driver name to request the IRQ. This makes it hard to identify interfaces from outputs like /proc/interrupts . So use the dev_name() for requesting instead. Signed-off-by: Stefan Wahren <wahrenst@gmx.net> Reviewed-by: Peng Fan <peng.fan@nxp.com> Link: https://lore.kernel.org/r/20250205091007.4528-1-wahrenst@gmx.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-14serial: 8250: Fix fifo underflow on flushJohn Keeping
When flushing the serial port's buffer, uart_flush_buffer() calls kfifo_reset() but if there is an outstanding DMA transfer then the completion function will consume data from the kfifo via uart_xmit_advance(), underflowing and leading to ongoing DMA as the driver tries to transmit another 2^32 bytes. This is readily reproduced with serial-generic and amidi sending even short messages as closing the device on exit will wait for the fifo to drain and in the underflow case amidi hangs for 30 seconds on exit in tty_wait_until_sent(). A trace of that gives: kworker/1:1-84 [001] 51.769423: bprint: serial8250_tx_dma: tx_size=3 fifo_len=3 amidi-763 [001] 51.769460: bprint: uart_flush_buffer: resetting fifo irq/21-fe530000-76 [000] 51.769474: bprint: __dma_tx_complete: tx_size=3 irq/21-fe530000-76 [000] 51.769479: bprint: serial8250_tx_dma: tx_size=4096 fifo_len=4294967293 irq/21-fe530000-76 [000] 51.781295: bprint: __dma_tx_complete: tx_size=4096 irq/21-fe530000-76 [000] 51.781301: bprint: serial8250_tx_dma: tx_size=4096 fifo_len=4294963197 irq/21-fe530000-76 [000] 51.793131: bprint: __dma_tx_complete: tx_size=4096 irq/21-fe530000-76 [000] 51.793135: bprint: serial8250_tx_dma: tx_size=4096 fifo_len=4294959101 irq/21-fe530000-76 [000] 51.804949: bprint: __dma_tx_complete: tx_size=4096 Since the port lock is held in when the kfifo is reset in uart_flush_buffer() and in __dma_tx_complete(), adding a flush_buffer hook to adjust the outstanding DMA byte count is sufficient to avoid the kfifo underflow. Fixes: 9ee4b83e51f74 ("serial: 8250: Add support for dmaengine") Cc: stable <stable@kernel.org> Signed-off-by: John Keeping <jkeeping@inmusicbrands.com> Link: https://lore.kernel.org/r/20250208124148.1189191-1-jkeeping@inmusicbrands.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-07fsnotify: use accessor to set FMODE_NONOTIFY_*Amir Goldstein
The FMODE_NONOTIFY_* bits are a 2-bits mode. Open coding manipulation of those bits is risky. Use an accessor file_set_fsnotify_mode() to set the mode. Rename file_set_fsnotify_mode() => file_set_fsnotify_mode_from_watchers() to make way for the simple accessor name. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Link: https://lore.kernel.org/r/20250203223205.861346-2-amir73il@gmail.com Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-06Revert "serial: Airoha SoC UART and HSUART support"Greg Kroah-Hartman
This reverts commit e12ebf14fa3654f68589292e645ae1ef74786638. It causes build errors in linux-next. Cc: Benjamin Larsson <benjamin.larsson@genexis.eu> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Link: https://lore.kernel.org/r/20250206135328.4bad1401@canb.auug.org.au Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-04serial: 8250_pnp: Remove unneeded ->iotype assignmentAndy Shevchenko
If ->iobase is set the default will be UPIO_PORT for ->iotype after the uart_read_and_validate_port_properties() call. Hence no need to assign that explicitly. Otherwise it will be UPIO_MEM. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250124161530.398361-7-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-04serial: 8250_platform: Remove unneeded ->iotype assignmentAndy Shevchenko
If ->iobase is set the default will be UPIO_PORT for ->iotype after the uart_read_and_validate_port_properties() call. Hence no need to assign that explicitly. Otherwise it will be UPIO_MEM. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250124161530.398361-6-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-04serial: 8250_of: Remove unneeded ->iotype assignmentAndy Shevchenko
If ->iobase is set the default will be UPIO_PORT for ->iotype after the uart_read_and_validate_port_properties() call. Hence no need to assign that explicitly. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250124161530.398361-5-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-04serial: port: Make ->iotype validation global in __uart_read_properties()Andy Shevchenko
In order to make code robust against potential changes in the future move ->iotype validation outside of switch in __uart_read_properties(). If any code will be added in between that might leave the ->iotype value unknown the validation catches this up. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250124161530.398361-4-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-04serial: port: Always update ->iotype in __uart_read_properties()Andy Shevchenko
The documentation of the __uart_read_properties() states that ->iotype member is always altered after the function call, but the code doesn't do that in the case when use_defaults == false and the value of reg-io-width is unsupported. Make sure the code follows the documentation. Note, the current users of the uart_read_and_validate_port_properties() will fail and the change doesn't affect their behaviour, neither users of uart_read_port_properties() will be affected since the alteration happens there even in the current code flow. Fixes: e894b6005dce ("serial: port: Introduce a common helper to read properties") Cc: stable <stable@kernel.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250124161530.398361-3-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-04serial: port: Assign ->iotype correctly when ->iobase is setAndy Shevchenko
Currently the ->iotype is always assigned to the UPIO_MEM when the respective property is not found. However, this will not support the cases when user wants to have UPIO_PORT to be set or preserved. Support this scenario by checking ->iobase value and default the ->iotype respectively. Fixes: 1117a6fdc7c1 ("serial: 8250_of: Switch to use uart_read_port_properties()") Fixes: e894b6005dce ("serial: port: Introduce a common helper to read properties") Cc: stable <stable@kernel.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250124161530.398361-2-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-04serial: sc16is7xx: Fix IRQ number check behaviorAndre Werner
The logical meaning of the previous version is wrong due to a typo. If the IRQ equals 0, no interrupt pin is available and polling mode shall be used. Additionally, this fix adds a check for IRQ < 0 to increase robustness, because documentation still says that negative IRQ values cannot be absolutely ruled-out. Fixes: 104c1b9dde9d ("serial: sc16is7xx: Add polling mode if no IRQ pin is available") Signed-off-by: Andre Werner <andre.werner@systec-electronic.com> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Maarten Brock <maarten.brock@sttls.nl> Reviewed-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Link: https://lore.kernel.org/r/20250121071819.1346672-1-andre.werner@systec-electronic.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-04serial: amba-pl011: Implement nbcon consoleToshiyuki Sato
Implement the callbacks required for an NBCON console [0] on the amba-pl011 console driver. Referred to the NBCON implementation work for 8250 [1] and imx [2]. The normal-priority write_thread checks for console ownership each time a character is printed. write_atomic holds the console ownership until the entire string is printed. UART register operations are protected from other contexts by uart_port_lock, except for a final flush(nbcon_atomic_flush_unsafe) on panic. The patch has been verified to correctly handle the output and competition of messages with different priorities and flushing panic message to console after nmi panic using ARM64 QEMU and a physical machine(A64FX). Stress testing was conducted on a physical machine(A64FX). The results are as follows: - The output speed and volume of messages using the NBCON console were comparable to the legacy console (data suggests a slight improvement). - When inducing a panic (sysrq-triggered or NMI) under heavy contention on the serial console output, the legacy console resulted in the loss of some or all crash messages. However, using the NBCON console, no message loss occurred. This testing referenced the NBCON console work for 8250 [3]. [0] https://lore.kernel.org/all/ZuRRTbapH0DCj334@pathway.suse.cz/ [1] https://lore.kernel.org/all/20240913140538.221708-1-john.ogness@linutronix.de/T/ [2] https://lore.kernel.org/linux-arm-kernel/20240913-serial-imx-nbcon-v3-1-4c627302335b@geanix.com/T/ [3] https://lore.kernel.org/lkml/ZsdoD6PomBRsB-ow@debarbos-thinkpadt14sgen2i.remote.csb/#t Signed-off-by: Toshiyuki Sato <fj6611ie@aa.jp.fujitsu.com> Link: https://lore.kernel.org/r/20250204044428.2191983-1-fj6611ie@aa.jp.fujitsu.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-04serial: 8250_dw: Drop unneeded NULL checks in dw8250_quirks()Andy Shevchenko
Since platform data is being provided for all supported hardware, no need to NULL check for it. Drop unneeded checks. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250203121456.3182891-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-04serial: mctrl_gpio: Remove unused mctrl_gpio_freeDr. David Alan Gilbert
mctrl_gpio_free() was added in 2014 by commit 84130aace839 ("tty/serial: Add GPIOLIB helpers for controlling modem lines") It does have a comment saying: '- * Normally, this function will not be called, as the GPIOs will - * be disposed of by the resource management code.' indeed, it doesn't seem to have been used since it was added. Remove it. Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org> Link: https://lore.kernel.org/r/20250129020048.245529-1-linux@treblig.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-04serial: Airoha SoC UART and HSUART supportBenjamin Larsson
Support for Airoha AN7581 SoC UART and HSUART baud rate calculation routine. Signed-off-by: Benjamin Larsson <benjamin.larsson@genexis.eu> Link: https://lore.kernel.org/r/20250119130105.2833517-3-benjamin.larsson@genexis.eu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-04tty/ldsem: Remove unused ldsem_down_write_trylockDr. David Alan Gilbert
ldsem_down_write_trylock() was added in 2013 by commit 4898e640caf0 ("tty: Add timed, writer-prioritized rw semaphore") but hasn't been used. Remove it. Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20250122012559.441006-1-linux@treblig.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-04serial: pch_uart: Remove legacy PM hookAndy Shevchenko
The legacy PM hook was never implemented. If we would like to achieve this, the entire serial subsystem should switch to use runtime PM first. For now, remove unneeded code. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250117141313.592645-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-04serial: mpc52xx_uart: Remove legacy PM hookAndy Shevchenko
The legacy PM hook was never implemented. If we would like to achieve this, the entire serial subsystem should switch to use runtime PM first. For now, remove unneeded code. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250117141304.592611-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-28Merge tag 'driver-core-6.14-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core and debugfs updates from Greg KH: "Here is the big set of driver core and debugfs updates for 6.14-rc1. Included in here is a bunch of driver core, PCI, OF, and platform rust bindings (all acked by the different subsystem maintainers), hence the merge conflict with the rust tree, and some driver core api updates to mark things as const, which will also require some fixups due to new stuff coming in through other trees in this merge window. There are also a bunch of debugfs updates from Al, and there is at least one user that does have a regression with these, but Al is working on tracking down the fix for it. In my use (and everyone else's linux-next use), it does not seem like a big issue at the moment. Here's a short list of the things in here: - driver core rust bindings for PCI, platform, OF, and some i/o functions. We are almost at the "write a real driver in rust" stage now, depending on what you want to do. - misc device rust bindings and a sample driver to show how to use them - debugfs cleanups in the fs as well as the users of the fs api for places where drivers got it wrong or were unnecessarily doing things in complex ways. - driver core const work, making more of the api take const * for different parameters to make the rust bindings easier overall. - other small fixes and updates All of these have been in linux-next with all of the aforementioned merge conflicts, and the one debugfs issue, which looks to be resolved "soon"" * tag 'driver-core-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (95 commits) rust: device: Use as_char_ptr() to avoid explicit cast rust: device: Replace CString with CStr in property_present() devcoredump: Constify 'struct bin_attribute' devcoredump: Define 'struct bin_attribute' through macro rust: device: Add property_present() saner replacement for debugfs_rename() orangefs-debugfs: don't mess with ->d_name octeontx2: don't mess with ->d_parent or ->d_parent->d_name arm_scmi: don't mess with ->d_parent->d_name slub: don't mess with ->d_name sof-client-ipc-flood-test: don't mess with ->d_name qat: don't mess with ->d_name xhci: don't mess with ->d_iname mtu3: don't mess wiht ->d_iname greybus/camera - stop messing with ->d_iname mediatek: stop messing with ->d_iname netdevsim: don't embed file_operations into your structs b43legacy: make use of debugfs_get_aux() b43: stop embedding struct file_operations into their objects carl9170: stop embedding file_operations into their objects ...
2025-01-28Merge tag 'tty-6.14-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty / serial driver updates from Greg KH: "Here is the tty/serial driver set of changes for 6.14-rc1. Nothing major in here, it was delayed a bit due to a regression found in linux-next which has now been reverted and verified that it is fixed. Other than the reverts, highlights include: - 8250 work to get the nbcon mode working (partially reverted) - altera_jtaguart minor fixes - fsl_lpuart minor updates - sh-sci driver minor updatesa - other tiny driver updates and cleanups All of these have been in linux-next for a while, and now with no reports of problems (thanks to the reverts)" * tag 'tty-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (44 commits) Revert "serial: 8250: Switch to nbcon console" Revert "serial: 8250: Revert "drop lockdep annotation from serial8250_clear_IER()"" serial: sh-sci: Increment the runtime usage counter for the earlycon device serial: sh-sci: Clean sci_ports[0] after at earlycon exit serial: sh-sci: Do not probe the serial port if its slot in sci_ports[] is in use serial: sh-sci: Move runtime PM enable to sci_probe_single() serial: sh-sci: Drop __initdata macro for port_cfg serial: kgdb_nmi: Remove unused knock code tty: Permit some TIOCL_SETSEL modes without CAP_SYS_ADMIN tty: xilinx_uartps: split sysrq handling serial: 8250: Revert "drop lockdep annotation from serial8250_clear_IER()" serial: 8250: Switch to nbcon console serial: 8250: Provide flag for IER toggling for RS485 serial: 8250: Use high-level writing function for FIFO serial: 8250: Use frame time to determine timeout serial: 8250: Adjust the timeout for FIFO mode tty: atmel_serial: Use of_property_present() for non-boolean properties serial: sc16is7xx: Add polling mode if no IRQ pin is available dt-bindings: serial: sc16is7xx: Add description for polling mode tty: serial: atmel: make it selectable for ARCH_LAN969X ...
2025-01-26Merge tag 'mm-nonmm-stable-2025-01-24-23-16' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull non-MM updates from Andrew Morton: "Mainly individually changelogged singleton patches. The patch series in this pull are: - "lib min_heap: Improve min_heap safety, testing, and documentation" from Kuan-Wei Chiu provides various tightenings to the min_heap library code - "xarray: extract __xa_cmpxchg_raw" from Tamir Duberstein preforms some cleanup and Rust preparation in the xarray library code - "Update reference to include/asm-<arch>" from Geert Uytterhoeven fixes pathnames in some code comments - "Converge on using secs_to_jiffies()" from Easwar Hariharan uses the new secs_to_jiffies() in various places where that is appropriate - "ocfs2, dlmfs: convert to the new mount API" from Eric Sandeen switches two filesystems to the new mount API - "Convert ocfs2 to use folios" from Matthew Wilcox does that - "Remove get_task_comm() and print task comm directly" from Yafang Shao removes now-unneeded calls to get_task_comm() in various places - "squashfs: reduce memory usage and update docs" from Phillip Lougher implements some memory savings in squashfs and performs some maintainability work - "lib: clarify comparison function requirements" from Kuan-Wei Chiu tightens the sort code's behaviour and adds some maintenance work - "nilfs2: protect busy buffer heads from being force-cleared" from Ryusuke Konishi fixes an issues in nlifs when the fs is presented with a corrupted image - "nilfs2: fix kernel-doc comments for function return values" from Ryusuke Konishi fixes some nilfs kerneldoc - "nilfs2: fix issues with rename operations" from Ryusuke Konishi addresses some nilfs BUG_ONs which syzbot was able to trigger - "minmax.h: Cleanups and minor optimisations" from David Laight does some maintenance work on the min/max library code - "Fixes and cleanups to xarray" from Kemeng Shi does maintenance work on the xarray library code" * tag 'mm-nonmm-stable-2025-01-24-23-16' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (131 commits) ocfs2: use str_yes_no() and str_no_yes() helper functions include/linux/lz4.h: add some missing macros Xarray: use xa_mark_t in xas_squash_marks() to keep code consistent Xarray: remove repeat check in xas_squash_marks() Xarray: distinguish large entries correctly in xas_split_alloc() Xarray: move forward index correctly in xas_pause() Xarray: do not return sibling entries from xas_find_marked() ipc/util.c: complete the kernel-doc function descriptions gcov: clang: use correct function param names latencytop: use correct kernel-doc format for func params minmax.h: remove some #defines that are only expanded once minmax.h: simplify the variants of clamp() minmax.h: move all the clamp() definitions after the min/max() ones minmax.h: use BUILD_BUG_ON_MSG() for the lo < hi test in clamp() minmax.h: reduce the #define expansion of min(), max() and clamp() minmax.h: update some comments minmax.h: add whitespace around operators and after commas nilfs2: do not update mtime of renamed directory that is not moved nilfs2: handle errors that nilfs_prepare_chunk() may return CREDITS: fix spelling mistake ...
2025-01-22Revert "serial: 8250: Switch to nbcon console"Greg Kroah-Hartman
This reverts commit b63e6f60eab45b16a1bf734fef9035a4c4187cd5. kernel test robot has found problems with this commit so revert it for now. Link: https://lore.kernel.org/r/202501221029.fb0d574d-lkp@intel.com Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202501221029.fb0d574d-lkp@intel.com Cc: John Ogness <john.ogness@linutronix.de> Cc: Petr Mladek <pmladek@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-22Revert "serial: 8250: Revert "drop lockdep annotation from ↵Greg Kroah-Hartman
serial8250_clear_IER()"" This reverts commit 422c9727b07f9f86e2ec11c56622e566221591cc. kernel test robot has found problems with this commit so revert it for now. Link: https://lore.kernel.org/r/202501221029.fb0d574d-lkp@intel.com Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202501221029.fb0d574d-lkp@intel.com Cc: John Ogness <john.ogness@linutronix.de> Cc: Petr Mladek <pmladek@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-17serial: sh-sci: Increment the runtime usage counter for the earlycon deviceClaudiu Beznea
In the sh-sci driver, serial ports are mapped to the sci_ports[] array, with earlycon mapped at index zero. The uart_add_one_port() function eventually calls __device_attach(), which, in turn, calls pm_request_idle(). The identified code path is as follows: uart_add_one_port() -> serial_ctrl_register_port() -> serial_core_register_port() -> serial_core_port_device_add() -> serial_base_port_add() -> device_add() -> bus_probe_device() -> device_initial_probe() -> __device_attach() -> // ... if (dev->p->dead) { // ... } else if (dev->driver) { // ... } else { // ... pm_request_idle(dev); // ... } The earlycon device clocks are enabled by the bootloader. However, the pm_request_idle() call in __device_attach() disables the SCI port clocks while earlycon is still active. The earlycon write function, serial_console_write(), calls sci_poll_put_char() via serial_console_putchar(). If the SCI port clocks are disabled, writing to earlycon may sometimes cause the SR.TDFE bit to remain unset indefinitely, causing the while loop in sci_poll_put_char() to never exit. On single-core SoCs, this can result in the system being blocked during boot when this issue occurs. To resolve this, increment the runtime PM usage counter for the earlycon SCI device before registering the UART port. Fixes: 0b0cced19ab1 ("serial: sh-sci: Add CONFIG_SERIAL_EARLYCON support") Cc: stable@vger.kernel.org Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com> Link: https://lore.kernel.org/r/20250116182249.3828577-6-claudiu.beznea.uj@bp.renesas.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-17serial: sh-sci: Clean sci_ports[0] after at earlycon exitClaudiu Beznea
The early_console_setup() function initializes sci_ports[0].port with an object of type struct uart_port obtained from the struct earlycon_device passed as an argument to early_console_setup(). Later, during serial port probing, the serial port used as earlycon (e.g., port A) might be remapped to a different position in the sci_ports[] array, and a different serial port (e.g., port B) might be assigned to slot 0. For example: sci_ports[0] = port B sci_ports[X] = port A In this scenario, the new port mapped at index zero (port B) retains the data associated with the earlycon configuration. Consequently, after the Linux boot process, any access to the serial port now mapped to sci_ports[0] (port B) will block the original earlycon port (port A). To address this, introduce an early_console_exit() function to clean up sci_ports[0] when earlycon is exited. To prevent the cleanup of sci_ports[0] while the serial device is still being used by earlycon, introduce the struct sci_port::probing flag and account for it in early_console_exit(). Fixes: 0b0cced19ab1 ("serial: sh-sci: Add CONFIG_SERIAL_EARLYCON support") Cc: stable@vger.kernel.org Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com> Link: https://lore.kernel.org/r/20250116182249.3828577-5-claudiu.beznea.uj@bp.renesas.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-17serial: sh-sci: Do not probe the serial port if its slot in sci_ports[] is ↵Claudiu Beznea
in use In the sh-sci driver, sci_ports[0] is used by earlycon. If the earlycon is still active when sci_probe() is called and the new serial port is supposed to map to sci_ports[0], return -EBUSY to prevent breaking the earlycon. This situation should occurs in debug scenarios, and users should be aware of the potential conflict. Fixes: 0b0cced19ab1 ("serial: sh-sci: Add CONFIG_SERIAL_EARLYCON support") Cc: stable@vger.kernel.org Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com> Link: https://lore.kernel.org/r/20250116182249.3828577-4-claudiu.beznea.uj@bp.renesas.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-17serial: sh-sci: Move runtime PM enable to sci_probe_single()Claudiu Beznea
Relocate the runtime PM enable operation to sci_probe_single(). This change prepares the codebase for upcoming fixes. While at it, replace the existing logic with a direct call to devm_pm_runtime_enable() and remove sci_cleanup_single(). The devm_pm_runtime_enable() function automatically handles disabling runtime PM during driver removal. Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com> Link: https://lore.kernel.org/r/20250116182249.3828577-3-claudiu.beznea.uj@bp.renesas.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-17serial: sh-sci: Drop __initdata macro for port_cfgClaudiu Beznea
The port_cfg object is used by serial_console_write(), which serves as the write function for the earlycon device. Marking port_cfg as __initdata causes it to be freed after kernel initialization, resulting in earlycon becoming unavailable thereafter. Remove the __initdata macro from port_cfg to resolve this issue. Fixes: 0b0cced19ab1 ("serial: sh-sci: Add CONFIG_SERIAL_EARLYCON support") Cc: stable@vger.kernel.org Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com> Fixes: 0b0cced19ab15c9e ("serial: sh-sci: Add CONFIG_SERIAL_EARLYCON support") Link: https://lore.kernel.org/r/20250116182249.3828577-2-claudiu.beznea.uj@bp.renesas.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-17serial: kgdb_nmi: Remove unused knock codeDr. David Alan Gilbert
kgdb_nmi_poll_knock() has been unused since it was added in 2013 in commit 0c57dfcc6c1d ("tty/serial: Add kgdb_nmi driver") Remove it, the static helpers, and module parameters it used. (The comment explaining why it might be used sounds sensible, but it's never been wired up, perhaps it's worth doing somewhere?) Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org> Link: https://lore.kernel.org/r/20250112135759.105541-1-linux@treblig.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-13tty: Permit some TIOCL_SETSEL modes without CAP_SYS_ADMINGünther Noack
With this, processes without CAP_SYS_ADMIN are able to use TIOCLINUX with subcode TIOCL_SETSEL, in the selection modes TIOCL_SETPOINTER, TIOCL_SELCLEAR and TIOCL_SELMOUSEREPORT. TIOCL_SETSEL was previously changed to require CAP_SYS_ADMIN, as this IOCTL let callers change the selection buffer and could be used to simulate keypresses. These three TIOCL_SETSEL selection modes, however, are safe to use, as they do not modify the selection buffer. This fixes a mouse support regression that affected Emacs (invisible mouse cursor). Cc: stable <stable@kernel.org> Link: https://lore.kernel.org/r/ee3ec63269b43b34e1c90dd8c9743bf8@finder.org Fixes: 8d1b43f6a6df ("tty: Restrict access to TIOCLINUX' copy-and-paste subcommands") Signed-off-by: Günther Noack <gnoack@google.com> Reviewed-by: Kees Cook <kees@kernel.org> Link: https://lore.kernel.org/r/20250110142122.1013222-1-gnoack@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-13tty: xilinx_uartps: split sysrq handlingSean Anderson
lockdep detects the following circular locking dependency: CPU 0 CPU 1 ========================== ============================ cdns_uart_isr() printk() uart_port_lock(port) console_lock() cdns_uart_console_write() if (!port->sysrq) uart_port_lock(port) uart_handle_break() port->sysrq = ... uart_handle_sysrq_char() printk() console_lock() The fixed commit attempts to avoid this situation by only taking the port lock in cdns_uart_console_write if port->sysrq unset. However, if (as shown above) cdns_uart_console_write runs before port->sysrq is set, then it will try to take the port lock anyway. This may result in a deadlock. Fix this by splitting sysrq handling into two parts. We use the prepare helper under the port lock and defer handling until we release the lock. Fixes: 74ea66d4ca06 ("tty: xuartps: Improve sysrq handling") Signed-off-by: Sean Anderson <sean.anderson@linux.dev> Cc: stable@vger.kernel.org # c980248179d: serial: xilinx_uartps: Use port lock wrappers Acked-by: John Ogness <john.ogness@linutronix.de> Link: https://lore.kernel.org/r/20250110213822.2107462-1-sean.anderson@linux.dev Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-13Merge 6.13-rc7 into tty-nextGreg Kroah-Hartman
We need the serial driver fixes in here to build on top of. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-13Merge 6.13-rc7 into driver-core-nextGreg Kroah-Hartman
We need the debugfs / driver-core fixes in here as well for testing and to build on top of. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-12drivers: remove get_task_comm() and print task comm directlyYafang Shao
Since task->comm is guaranteed to be NUL-terminated, we can print it directly without the need to copy it into a separate buffer. This simplifies the code and avoids unnecessary operations. Link: https://lkml.kernel.org/r/20241219023452.69907-6-laoar.shao@gmail.com Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> (For tty) Reviewed-by: Lyude Paul <lyude@redhat.com> (For nouveau) Cc: Oded Gabbay <ogabbay@kernel.org> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Tvrtko Ursulin <tursulin@ursulin.net> Cc: David Airlie <airlied@gmail.com> Cc: Simona Vetter <simona@ffwll.ch> Cc: Karol Herbst <kherbst@redhat.com> Cc: Lyude Paul <lyude@redhat.com> Cc: Danilo Krummrich <dakr@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jirislaby@kernel.org> Cc: "André Almeida" <andrealmeid@igalia.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Borislav Petkov (AMD) <bp@alien8.de> Cc: Darren Hart <dvhart@infradead.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Morris <jmorris@namei.org> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Kalle Valo <kvalo@kernel.org> Cc: Kees Cook <kees@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Moore <paul@paul-moore.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vineet Gupta <vgupta@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-01-10serial: 8250: Revert "drop lockdep annotation from serial8250_clear_IER()"John Ogness
The 8250 driver no longer depends on @oops_in_progress and will no longer violate the port->lock locking constraints. This reverts commit 3d9e6f556e235ddcdc9f73600fdd46fe1736b090. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20250107212702.169493-7-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-10serial: 8250: Switch to nbcon consoleJohn Ogness
Implement the necessary callbacks to switch the 8250 console driver to perform as an nbcon console. Add implementations for the nbcon console callbacks: ->write_atomic() ->write_thread() ->device_lock() ->device_unlock() and add CON_NBCON to the initial @flags. All register access in the callbacks are within unsafe sections. The ->write_atomic() and ->write_thread() callbacks allow safe handover/takeover per byte and add a preceding newline if they take over from another context mid-line. For the ->write_atomic() callback, a new irq_work is used to defer modem control since it may be called from a context that does not allow waking up tasks. Note: A new __serial8250_clear_IER() is introduced for direct clearing of UART_IER. This will allow to restore the lockdep check to serial8250_clear_IER() in a follow-up commit. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Tested-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20250107212702.169493-6-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-10serial: 8250: Provide flag for IER toggling for RS485John Ogness
For RS485 mode, if SER_RS485_RX_DURING_TX is not available, the console ->write() callback needs to enable/disable Tx. It does this by calling the ->rs485_start_tx() and ->rs485_stop_tx() callbacks. However, some of these callbacks also disable/enable interrupts and makes power management calls. This causes 2 problems for console writing: 1. A console write can occur in contexts that are illegal for pm_runtime_*(). It is not even necessary for console writing to use pm_runtime_*() because a console already does this in serial8250_console_setup() and serial8250_console_exit(). 2. The console ->write() callback already handles disabling/enabling the interrupts by properly restoring the previous IER value. Add an argument @toggle_ier to the ->rs485_start_tx() and ->rs485_stop_tx() callbacks to specify if they may disable/enable receive interrupts while using pm_runtime_*(). Console writing will not allow the toggling. For all call sites other than console writing there is no functional change. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20250107212702.169493-5-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>