summaryrefslogtreecommitdiff
path: root/drivers/platform/x86/serdev_helpers.h
AgeCommit message (Collapse)AuthorFilesLines
2024-12-10platform/x86: serdev_helpers: Add get_serdev_controller_from_parent() helperHans de Goede1-26/+34
The x86-android-tablets code needs to be able to get a serdev_controller device from a PCI parent, rather then by the ACPI HID+UID of the parent, because on some tablets the UARTs are enumerated as PCI devices instead of ACPI devices. Split the code to walk the device hierarchy to find the serdev_controller from its parents out into a get_serdev_controller_from_parent() helper so that the x86-android-tablets code can re-use it. Reviewed-by: Andy Shevchenko <andy@kernel.org> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Link: https://lore.kernel.org/r/20241204204227.95757-5-hdegoede@redhat.com Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2024-12-10platform/x86: serdev_helpers: Check for serial_ctrl_uid == NULLHans de Goede1-2/+2
dell_uart_bl_pdev_probe() calls get_serdev_controller() with the serial_ctrl_uid parameter set to NULL. In case of errors this NULL parameter then gets passed to pr_err() as argument matching a "%s" conversion specification. This leads to compiler warnings when building with "make W=1". Check serial_ctrl_uid before passing it to pr_err() to avoid these. Fixes: dc5afd720f84 ("platform/x86: Add new get_serdev_controller() helper") Cc: stable@vger.kernel.org Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Andy Shevchenko <andy@kernel.org> Link: https://lore.kernel.org/r/20241204204227.95757-4-hdegoede@redhat.com Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2024-02-20platform/x86: Add new get_serdev_controller() helperHans de Goede1-0/+80
In some cases UART attached devices which require an in kernel driver, e.g. UART attached Bluetooth HCIs are described in the ACPI tables by an ACPI device with a broken or missing UartSerialBusV2() resource. This causes the kernel to create a /dev/ttyS# char-device for the UART instead of creating an in kernel serdev-controller + serdev-device pair for the in kernel driver. The quirk handling in acpi_quirk_skip_serdev_enumeration() makes the kernel create a serdev-controller device for these UARTs instead of a /dev/ttyS#. Instantiating the actual serdev-device to bind to is up to pdx86 code, so far this was handled by the x86-android-tablets code. But since commit b286f4e87e32 ("serial: core: Move tty and serdev to be children of serial core port device") the serdev-controller device has moved in the device hierarchy from (e.g.) /sys/devices/pci0000:00/8086228A:00/serial0 to /sys/devices/pci0000:00/8086228A:00/8086228A:00:0/8086228A:00:0.0/serial0 . This makes this a bit trickier to do and another driver is in the works which will also need this functionality. Add a new helper to get the serdev-controller device, so that the new code for this can be shared. Fixes: b286f4e87e32 ("serial: core: Move tty and serdev to be children of serial core port device") Cc: Tony Lindgren <tony@atomide.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Link: https://lore.kernel.org/r/20240216201721.239791-3-hdegoede@redhat.com