Re: [PATCH v3 1/2] serdev: Split and export serdev_acpi_get_uart_resource()

[Hans de Goede]

Hi,

On 8/6/21 1:17 PM, Andy Shevchenko wrote:
> The same as for I²C Serial Bus resource split and export
> serdev_acpi_get_uart_resource(). We have already a few users
> one of which is converted here.
> 
> Rationale of this is to consolidate parsing UART Serial Bus
> resource in one place as it's done, e.g., for I²C Serial Bus.
> 
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> Reviewed-by: Hans de Goede <hdegoede@xxxxxxxxxx>

As mentioned before I believe it is best if this series is
merged in its entirety through to the tty tree, here is my
ack for patch 2/2 for that:

Acked-by: Hans de Goede <hdegoede@xxxxxxxxxx>

Greg, can you pickup the entire series please?

Regards,

Hans


> ---
> v3: amended kernel doc to have RETURN section (Jiri)
>  drivers/tty/serdev/core.c | 36 +++++++++++++++++++++++++++++-------
>  include/linux/serdev.h    | 14 ++++++++++++++
>  2 files changed, 43 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c
> index 92498961fd92..f1324fe99378 100644
> --- a/drivers/tty/serdev/core.c
> +++ b/drivers/tty/serdev/core.c
> @@ -562,23 +562,45 @@ struct acpi_serdev_lookup {
>  	int index;
>  };
>  
> +/**
> + * serdev_acpi_get_uart_resource - Gets UARTSerialBus resource if type matches
> + * @ares:	ACPI resource
> + * @uart:	Pointer to UARTSerialBus resource will be returned here
> + *
> + * Checks if the given ACPI resource is of type UARTSerialBus.
> + * In this case, returns a pointer to it to the caller.
> + *
> + * Return: True if resource type is of UARTSerialBus, otherwise false.
> + */
> +bool serdev_acpi_get_uart_resource(struct acpi_resource *ares,
> +				   struct acpi_resource_uart_serialbus **uart)
> +{
> +	struct acpi_resource_uart_serialbus *sb;
> +
> +	if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
> +		return false;
> +
> +	sb = &ares->data.uart_serial_bus;
> +	if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_UART)
> +		return false;
> +
> +	*uart = sb;
> +	return true;
> +}
> +EXPORT_SYMBOL_GPL(serdev_acpi_get_uart_resource);
> +
>  static int acpi_serdev_parse_resource(struct acpi_resource *ares, void *data)
>  {
>  	struct acpi_serdev_lookup *lookup = data;
>  	struct acpi_resource_uart_serialbus *sb;
>  	acpi_status status;
>  
> -	if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
> -		return 1;
> -
> -	if (ares->data.common_serial_bus.type != ACPI_RESOURCE_SERIAL_TYPE_UART)
> +	if (!serdev_acpi_get_uart_resource(ares, &sb))
>  		return 1;
>  
>  	if (lookup->index != -1 && lookup->n++ != lookup->index)
>  		return 1;
>  
> -	sb = &ares->data.uart_serial_bus;
> -
>  	status = acpi_get_handle(lookup->device_handle,
>  				 sb->resource_source.string_ptr,
>  				 &lookup->controller_handle);
> @@ -586,7 +608,7 @@ static int acpi_serdev_parse_resource(struct acpi_resource *ares, void *data)
>  		return 1;
>  
>  	/*
> -	 * NOTE: Ideally, we would also want to retreive other properties here,
> +	 * NOTE: Ideally, we would also want to retrieve other properties here,
>  	 * once setting them before opening the device is supported by serdev.
>  	 */
>  
> diff --git a/include/linux/serdev.h b/include/linux/serdev.h
> index 9f14f9c12ec4..3368c261ab62 100644
> --- a/include/linux/serdev.h
> +++ b/include/linux/serdev.h
> @@ -327,4 +327,18 @@ static inline int serdev_tty_port_unregister(struct tty_port *port)
>  }
>  #endif /* CONFIG_SERIAL_DEV_CTRL_TTYPORT */
>  
> +struct acpi_resource;
> +struct acpi_resource_uart_serialbus;
> +
> +#ifdef CONFIG_ACPI
> +bool serdev_acpi_get_uart_resource(struct acpi_resource *ares,
> +				   struct acpi_resource_uart_serialbus **uart);
> +#else
> +static inline bool serdev_acpi_get_uart_resource(struct acpi_resource *ares,
> +						 struct acpi_resource_uart_serialbus **uart)
> +{
> +	return false;
> +}
> +#endif /* CONFIG_ACPI */
> +
>  #endif /*_LINUX_SERDEV_H */
>