Re: [PATCH v4 2/9] serdev: Add an API to find the serdev controller associated with the devicetree node

[Bartosz Golaszewski]

On Mon, 12 Jan 2026 17:26:01 +0100, Manivannan Sadhasivam via B4 Relay
<devnull+manivannan.sadhasivam.oss.qualcomm.com@xxxxxxxxxx> said:
> From: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxxxxxxxx>
>
> Add of_find_serdev_controller_by_node() API to find the serdev controller
> device associated with the devicetree node.
>
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxxxxxxxx>
> ---
>  drivers/tty/serdev/core.c | 16 ++++++++++++++++
>  include/linux/serdev.h    |  9 +++++++++
>  2 files changed, 25 insertions(+)
>
> diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c
> index b33e708cb245..25382c2d63e6 100644
> --- a/drivers/tty/serdev/core.c
> +++ b/drivers/tty/serdev/core.c
> @@ -504,6 +504,22 @@ struct serdev_controller *serdev_controller_alloc(struct device *host,
>  }
>  EXPORT_SYMBOL_GPL(serdev_controller_alloc);
>
> +/**
> + * of_find_serdev_controller_by_node() - Find the serdev controller associated
> + *					 with the devicetree node
> + * @node:	Devicetree node
> + *
> + * Return: Pointer to the serdev controller associated with the node. NULL if
> + * the controller is not found.
> + */

Please also say that the caller is responsible for calling
serdev_controller_put() on the returned object.

Bart

> +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);
> +
> +	return (dev && dev->type == &serdev_ctrl_type) ? to_serdev_controller(dev) : NULL;
> +}
> +EXPORT_SYMBOL_GPL(of_find_serdev_controller_by_node);
> +
>  static int of_serdev_register_devices(struct serdev_controller *ctrl)
>  {
>  	struct device_node *node;
> diff --git a/include/linux/serdev.h b/include/linux/serdev.h
> index ecde0ad3e248..db9bfaba0662 100644
> --- a/include/linux/serdev.h
> +++ b/include/linux/serdev.h
> @@ -333,4 +333,13 @@ static inline bool serdev_acpi_get_uart_resource(struct acpi_resource *ares,
>  }
>  #endif /* CONFIG_ACPI */
>
> +#ifdef CONFIG_OF
> +struct serdev_controller *of_find_serdev_controller_by_node(struct device_node *node);
> +#else
> +struct serdev_controller *of_find_serdev_controller_by_node(struct device_node *node)
> +{
> +	return NULL;
> +}
> +#endif /* CONFIG_OF */
> +
>  #endif /*_LINUX_SERDEV_H */
>
> --
> 2.48.1
>
>
>