From: Vaishnav M A <vaishnav@xxxxxxxxxxxxxxx> add of_find_serdev_controller_by_node to obtain a serdev_controller from the device_node, which can help if the serdev_device is not described over device tree and instantiation of the device happens from a different driver, for the same purpose an option to not delete an empty serdev controller is added. Signed-off-by: Vaishnav M A <vaishnav@xxxxxxxxxxxxxxx> Signed-off-by: Ayush Singh <ayushdevel1325@xxxxxxxxx> --- drivers/tty/serdev/core.c | 19 +++++++++++++++++++ include/linux/serdev.h | 4 ++++ 2 files changed, 23 insertions(+) diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c index 613cb356b918..5b5b3f2b2e42 100644 --- a/drivers/tty/serdev/core.c +++ b/drivers/tty/serdev/core.c @@ -555,6 +555,19 @@ static int of_serdev_register_devices(struct serdev_controller *ctrl) return 0; } +#if defined(CONFIG_OF) +struct serdev_controller *of_find_serdev_controller_by_node(struct device_node *node) +{ + struct device *dev = bus_find_device_by_of_node(&serdev_bus_type, node); + + if (!dev) + return NULL; + + return (dev->type == &serdev_ctrl_type) ? to_serdev_controller(dev) : NULL; +} +EXPORT_SYMBOL_GPL(of_find_serdev_controller_by_node); +#endif + #ifdef CONFIG_ACPI #define SERDEV_ACPI_MAX_SCAN_DEPTH 32 @@ -785,6 +798,12 @@ int serdev_controller_add(struct serdev_controller *ctrl) pm_runtime_enable(&ctrl->dev); + /* provide option to not delete a serdev controller without devices + * if property is present + */ + if (device_property_present(&ctrl->dev, "force-empty-serdev-controller")) + return 0; + ret_of = of_serdev_register_devices(ctrl); ret_acpi = acpi_serdev_register_devices(ctrl); if (ret_of && ret_acpi) { diff --git a/include/linux/serdev.h b/include/linux/serdev.h index ff78efc1f60d..287d7b9bc10a 100644 --- a/include/linux/serdev.h +++ b/include/linux/serdev.h @@ -117,6 +117,10 @@ static inline struct serdev_controller *to_serdev_controller(struct device *d) return container_of(d, struct serdev_controller, dev); } +#if defined(CONFIG_OF) +struct serdev_controller *of_find_serdev_controller_by_node(struct device_node *node); +#endif + static inline void *serdev_device_get_drvdata(const struct serdev_device *serdev) { return dev_get_drvdata(&serdev->dev); -- 2.44.0