kernel/drivers/tty/serial/8250/8250_platform.c, branch linux-rolling-stable

Merge tag 'tty-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

2025-12-07T02:38:19Z

Pull tty/serial updates from Greg KH: "Here is the big set of tty/serial driver changes for 6.19-rc1. Nothing major at all, just small constant churn to make the tty layer "cleaner" as well as serial driver updates and even a new test added! Included in here are: - More tty/serial cleanups from Jiri - tty tiocsti test added to hopefully ensure we don't regress in this area again - sc16is7xx driver updates - imx serial driver updates - 8250 driver updates - new hardware device ids added - other minor serial/tty driver cleanups and tweaks All of these have been in linux-next for a while with no reported issues" * tag 'tty-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (60 commits) serial: sh-sci: Fix deadlock during RSCI FIFO overrun error dt-bindings: serial: rsci: Drop "uart-has-rtscts: false" LoongArch: dts: Add uart new compatible string serial: 8250: Add Loongson uart driver support dt-bindings: serial: 8250: Add Loongson uart compatible serial: 8250: add driver for KEBA UART serial: Keep rs485 settings for devices without firmware node serial: qcom-geni: Enable Serial on SA8255p Qualcomm platforms serial: qcom-geni: Enable PM runtime for serial driver serial: sprd: Return -EPROBE_DEFER when uart clock is not ready tty: serial: samsung: Declare earlycon for Exynos850 serial: icom: Convert PCIBIOS_* return codes to errnos serial: 8250-of: Fix style issues in 8250_of.c serial: add support of CPCI cards serial: mux: Fix kernel doc for mux_poll() tty: replace use of system_unbound_wq with system_dfl_wq serial: 8250_platform: simplify IRQF_SHARED handling serial: 8250: make share_irqs local to 8250_platform serial: 8250: move skip_txen_test to core serial: drop SERIAL_8250_DEPRECATED_OPTIONS ...

serial: 8250: Fix 8250_rsa symbol loop

2025-11-26T12:16:53Z

Depmod fails for a kernel made with: make allnoconfig echo -e "CONFIG_MODULES=y\nCONFIG_SERIAL_8250=m\nCONFIG_SERIAL_8250_EXTENDED=y\nCONFIG_SERIAL_8250_RSA=y" >> .config make olddefconfig ...due to a dependency loop: depmod: ERROR: Cycle detected: 8250 -> 8250_base -> 8250 depmod: ERROR: Found 2 modules in dependency cycles! This is caused by the move of 8250 RSA code from 8250_port.c (in 8250_base.ko) into 8250_rsa.c (in 8250.ko) by the commit 5a128fb475fb ("serial: 8250: move RSA functions to 8250_rsa.c"). The commit b20d6576cdb3 ("serial: 8250: export RSA functions") tried to fix a missing symbol issue with EXPORTs but those then cause this dependency cycle. Break dependency loop by moving 8250_rsa.o from 8250.ko to 8250_base.ko and by passing univ8250_port_base_ops to univ8250_rsa_support() that can make a local copy of it. Reported-by: Stephen Rothwell Reported-by: Alex Davis Fixes: 5a128fb475fb ("serial: 8250: move RSA functions to 8250_rsa.c") Fixes: b20d6576cdb3 ("serial: 8250: export RSA functions") Cc: stable Link: https://lore.kernel.org/all/87frc3sd8d.fsf@posteo.net/ Link: https://lore.kernel.org/all/CADiockCvM6v+d+UoFZpJSMoLAdpy99_h-hJdzUsdfaWGn3W7-g@mail.gmail.com/ Reviewed-by: Andy Shevchenko Reviewed-by: Jiri Slaby Signed-off-by: Ilpo Järvinen Link: https://patch.msgid.link/20251110105043.4062-1-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman

serial: 8250_platform: simplify IRQF_SHARED handling

2025-11-21T17:31:27Z

IRQF_SHARED is the only flag handled in __serial8250_isa_init_ports() and serial8250_probe_platform(). There is no need to precompute the flags. Instead, initialize port->irqflags directly in the for loop. Note the "if (bool)" is cheap and these are not hot paths anyway. Signed-off-by: Jiri Slaby (SUSE) Link: https://patch.msgid.link/20251119092457.826789-7-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

serial: 8250: make share_irqs local to 8250_platform

2025-11-21T17:31:27Z

share_irqs is used solely in 8250_platform. Make it local to that file. Signed-off-by: Jiri Slaby (SUSE) Link: https://patch.msgid.link/20251119092457.826789-6-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

serial: 8250: move skip_txen_test to core

2025-11-21T17:31:27Z

8250_core is the only place where skip_txen_test is used. And platform and core end up in 8250.ko, so there is no change in module name (param prefix). Therefore, move skip_txen_test there and make it local. Signed-off-by: Jiri Slaby (SUSE) Link: https://patch.msgid.link/20251119092457.826789-5-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

serial: drop SERIAL_8250_DEPRECATED_OPTIONS

2025-11-21T17:31:27Z

In 3.7, 8250 was unintentionally renamed to 8250_core. This happened in the commit 835d844d1a28 (8250_pnp: do pnp probe before legacy probe). This made 8250. module options effectively defunct. Instead, 8250_core. worked. In 3.9, the commit f2b8dfd9e480 (serial: 8250: Keep 8250. module options functional after driver rename) made the original options work again by introducing a hack. Later in 3.9, the commit 9196d8acd7f9 (TTY: 8250, revert module name change) changed the module name back to 8250 (from 8250_core). Since then, the hack was there to support the transient 8250_core. options. Those were present only in the 3.7..3.9 range. These transient options were deprecated by 9326b047e4fd (TTY: 8250, deprecated 8250_core.* options) in v3.9 too. Now, after those 12 years, it is time to get rid of this hack completely. Signed-off-by: Jiri Slaby (SUSE) Link: https://patch.msgid.link/20251119092457.826789-4-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

serial: 8250_platform: Reduce stack usage in serial8250_probe_platform()

2025-08-14T09:58:50Z

The function serial8250_probe_platform() in 8250_platform.c triggered a frame size warning: drivers/tty/serial/8250/8250_platform.c: In function ‘serial8250_probe_platform.isra’: drivers/tty/serial/8250/8250_platform.c:201:1: warning: the frame size of 1184 bytes is larger than 1024 bytes [-Wframe-larger-than=] This patch reduces the stack usage by dynamically allocating the `uart` structure using kzalloc(), rather than placing it on the stack. This eliminates the overflow warning and improves kernel robustness. Signed-off-by: Abinash Singh Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20250806215134.4921-3-abinashsinghlalotra@gmail.com Signed-off-by: Greg Kroah-Hartman

serial: 8250_platform: Reduce stack usage in serial8250_probe_acpi()

2025-08-14T09:58:50Z

The function serial8250_probe_acpi() in 8250_platform.c triggered a frame size warning: drivers/tty/serial/8250/8250_platform.c: In function ‘serial8250_probe_acpi’: drivers/tty/serial/8250/8250_platform.c:152:1: warning: the frame size of 1160 bytes is larger than 1024 bytes [-Wframe-larger-than=] This patch reduces the stack usage by dynamically allocating the `uart` structure using kzalloc(), rather than placing it on the stack. This eliminates the overflow warning and improves kernel robustness. Signed-off-by: Abinash Singh Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20250806215134.4921-2-abinashsinghlalotra@gmail.com Signed-off-by: Greg Kroah-Hartman

serial: 8250_platform: Remove unneeded ->iotype assignment

2025-02-04T13:44:52Z

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 Link: https://lore.kernel.org/r/20250124161530.398361-6-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman

serial: Switch back to struct platform_driver::remove()

2024-10-11T06:13:28Z

After commit 0edb555a65d1 ("platform: Make platform_driver::remove() return void") .remove() is (again) the right callback to implement for platform drivers. Convert all platform drivers below drivers/tty/serial to use .remove(), with the eventual goal to drop struct platform_driver::remove_new(). As .remove() and .remove_new() have the same prototypes, conversion is done by just changing the structure member name in the driver initializer. Signed-off-by: Uwe Kleine-König Link: https://lore.kernel.org/r/20241007205803.444994-7-u.kleine-koenig@baylibre.com Signed-off-by: Greg Kroah-Hartman