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2025-03-20tty: n_tty: extract n_tty_continue_cookie() from n_tty_read()Jiri Slaby (SUSE)
n_tty_read() is a very long function doing too much of different stuff. Extract the "cookie" (continuation read) handling to a separate function: n_tty_continue_cookie(). Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20250317070046.24386-10-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-20tty: n_tty: drop n_tty_trace()Jiri Slaby (SUSE)
This n_tty_trace() is an always disabled debugging macro. It comes from commit 32f13521ca68 ("n_tty: Line copy to user buffer in canonical mode"). Drop it as it is dead for over a decade. Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20250317070046.24386-9-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-20tty: n_tty: clean up process_output_block()Jiri Slaby (SUSE)
* Use guard(mutex), which results in: - the function can return directly when "space == 0". - "i" can now be "unsigned" as it is no longer abused to hold a retval from tty->ops->write(). Note the compared-to "nr" is already "unsigned". * The end label is now dubbed "do_write" as that is what happens there. Unlike the uncertain "break_out" name. Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20250317070046.24386-8-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-20tty: n_tty: simplify process_output()Jiri Slaby (SUSE)
Using guard(mutex), the function can be written in a much more efficient way. Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20250317070046.24386-7-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-20tty: n_tty: use uint for space returned by tty_write_room()Jiri Slaby (SUSE)
tty_write_room() returns an "unsigned int". So in case some insane driver (like my tty test driver) returns (legitimate) UINT_MAX from its tty_operations::write_room(), n_tty is confused on several places. For example, in process_output_block(), the result of tty_write_room() is stored into (signed) "int". So this UINT_MAX suddenly becomes -1. And that is extended to ssize_t and returned from process_output_block(). This causes a write() to such a node to receive -EPERM (which is -1). Fix that by using proper "unsigned int" and proper "== 0" test. And return 0 constant directly in that "if", so that it is immediately clear what is returned ("space" equals to 0 at that point). Similarly for process_output() and __process_echoes(). Note this does not fix any in-tree driver as of now. If you want "Fixes: something", it would be commit 03b3b1a2405c ("tty: make tty_operations::write_room return uint"). I intentionally do not mark this patch by a real tag below. Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20250317070046.24386-6-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-20tty: move N_TTY_BUF_SIZE to n_ttyJiri Slaby (SUSE)
"N_TTY_BUF_SIZE" is private to n_tty and shall not be exposed to the world. Definitely not in tty.h somewhere in the middle of "struct tty_struct". This is a remnant of moving "read_flags" to "struct n_tty_data" in commit 3fe780b379fa ("TTY: move ldisc data from tty_struct: bitmaps"). But some cleanup was needed first (in previous patches). Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20250317070046.24386-5-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-20tty: audit: do not use N_TTY_BUF_SIZEJiri Slaby (SUSE)
N_TTY_BUF_SIZE -- as the name suggests -- is the N_TTY's buffer size. There is no reason to couple that to audit's buffer size, so define an own TTY_AUDIT_BUF_SIZE macro (with the same size). N_TTY_BUF_SIZE is private and will be moved to n_tty.c later. Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20250317070046.24386-3-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-17printk: Add an option to allow ttynull to be a default console deviceAdam Simonelli
The new option is CONFIG_NULL_TTY_DEFAULT_CONSOLE. if enabled, and CONFIG_VT is disabled, ttynull will become the default primary console device. ttynull will be the only console device usually with this option enabled. Some architectures do call add_preferred_console() which may add another console though. Motivation: Many distributions ship with CONFIG_VT enabled. On tested desktop hardware if CONFIG_VT is disabled, the default console device falls back to /dev/ttyS0 instead of /dev/tty. This could cause issues in user space, and hardware problems: 1. The user space issues include the case where /dev/ttyS0 is disconnected, and the TCGETS ioctl, which some user space libraries use as a probe to determine if a file is a tty, is called on /dev/console and fails. Programs that call isatty() on /dev/console and get an incorrect false value may skip expected logging to /dev/console. 2. The hardware issues include the case if a user has a science instrument or other device connected to the /dev/ttyS0 port, and they were to upgrade to a kernel that is disabling the CONFIG_VT option, kernel logs will then be sent to the device connected to /dev/ttyS0 unless they edit their kernel command line manually. The new CONFIG_NULL_TTY_DEFAULT_CONSOLE option will give users and distribution maintainers an option to avoid this. Disabling CONFIG_VT and enabling CONFIG_NULL_TTY_DEFAULT_CONSOLE will ensure the default kernel console behavior is not dependent on hardware configuration by default, and avoid unexpected new behavior on devices connected to the /dev/ttyS0 serial port. Reviewed-by: Petr Mladek <pmladek@suse.com> Tested-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Adam Simonelli <adamsimonelli@gmail.com> Link: https://lore.kernel.org/r/20250314160749.3286153-2-adamsimonelli@gmail.com [pmladek@suse.com: Fixed indentation of the commit message.] Signed-off-by: Petr Mladek <pmladek@suse.com>
2025-03-11printk: Rename console_start to console_resumeMarcos Paulo de Souza
The intent of console_start was to resume a previously suspended console, so rename it accordingly. Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Reviewed-by: John Ogness <john.ogness@linutronix.de> Link: https://lore.kernel.org/r/20250226-printk-renaming-v1-4-0b878577f2e6@suse.com [pmladek@suse.com: Fixed typo in the commit message. Updated also new drm_log.c.] Signed-off-by: Petr Mladek <pmladek@suse.com>
2025-03-11printk: Rename console_stop to console_suspendMarcos Paulo de Souza
The intent of console_stop was in fact to suspend it, so rename the function accordingly. Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Reviewed-by: John Ogness <john.ogness@linutronix.de> Link: https://lore.kernel.org/r/20250226-printk-renaming-v1-3-0b878577f2e6@suse.com [pmladek@suse.com: Fixed typo in the commit message. Updated also new drm_log.c] Signed-off-by: Petr Mladek <pmladek@suse.com>
2025-03-04s390: Convert MACHINE_IS_[LPAR|VM|KVM], etc, machine_is_[lpar|vm|kvm]()Heiko Carstens
Move machine type detection to the decompressor and use static branches to implement and use machine_is_[lpar|vm|kvm]() instead of a runtime check via MACHINE_IS_[LPAR|VM|KVM]. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-02-20serial: 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. Acked-by: Zack Rusin <zack.rusin@broadcom.com> Signed-off-by: Nam Cao <namcao@linutronix.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/4a028a23126b3350a5e243dcb49e1ef1b2a4b740.1738746904.git.namcao@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-20serial: 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. Acked-by: Zack Rusin <zack.rusin@broadcom.com> Signed-off-by: Nam Cao <namcao@linutronix.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/c21664d013015584aebbb6bb8cedd748182cb551.1738746904.git.namcao@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-20serial: 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. Acked-by: Zack Rusin <zack.rusin@broadcom.com> Signed-off-by: Nam Cao <namcao@linutronix.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/ad27070bc67c13f8a9acbd5cbf4cbae72797e3e1.1738746904.git.namcao@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-20serial: 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> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/78e8c0d1b38998eab983fad265751ed13c2b9009.1738746904.git.namcao@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-20serial: 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. Acked-by: Zack Rusin <zack.rusin@broadcom.com> Signed-off-by: Nam Cao <namcao@linutronix.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/991926d130cc272df30d226760d5d74187991669.1738746904.git.namcao@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-20serial: 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> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/af7823518fb060c6c97105a2513cfc61adbdf38f.1738746927.git.namcao@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 ...