Re: [PATCH v6 4/9] spi: Add API to count spi acpi resources

From: Hans de Goede
Date: Tue Feb 01 2022 - 09:42:17 EST


Hi,

On 1/21/22 18:24, Stefan Binding wrote:
> Some ACPI nodes may have more than one Spi Resource.
> To be able to handle these case, its necessary to have
> a way of counting these resources.
>
> Signed-off-by: Stefan Binding <sbinding@xxxxxxxxxxxxxxxxxxxxx>

Thanks, patch looks good to me:

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

Regards,

Hans


> ---
> drivers/spi/spi.c | 40 ++++++++++++++++++++++++++++++++++++++++
> include/linux/spi/spi.h | 1 +
> 2 files changed, 41 insertions(+)
>
> diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
> index 06c0a308b38b..ec9f2ed579e3 100644
> --- a/drivers/spi/spi.c
> +++ b/drivers/spi/spi.c
> @@ -2324,6 +2324,46 @@ struct acpi_spi_lookup {
> int index;
> };
>
> +static int acpi_spi_count(struct acpi_resource *ares, void *data)
> +{
> + struct acpi_resource_spi_serialbus *sb;
> + int *count = data;
> +
> + if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
> + return 1;
> +
> + sb = &ares->data.spi_serial_bus;
> + if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_SPI)
> + return 1;
> +
> + *count = *count + 1;
> +
> + return 1;
> +}
> +
> +/**
> + * acpi_spi_count_resources - Count the number of SpiSerialBus resources
> + * @adev: ACPI device
> + *
> + * Returns the number of SpiSerialBus resources in the ACPI-device's
> + * resource-list; or a negative error code.
> + */
> +int acpi_spi_count_resources(struct acpi_device *adev)
> +{
> + LIST_HEAD(r);
> + int count = 0;
> + int ret;
> +
> + ret = acpi_dev_get_resources(adev, &r, acpi_spi_count, &count);
> + if (ret < 0)
> + return ret;
> +
> + acpi_dev_free_resource_list(&r);
> +
> + return count;
> +}
> +EXPORT_SYMBOL_GPL(acpi_spi_count_resources);
> +
> static void acpi_spi_parse_apple_properties(struct acpi_device *dev,
> struct acpi_spi_lookup *lookup)
> {
> diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
> index e5bbb9cbd3d7..394b4241d989 100644
> --- a/include/linux/spi/spi.h
> +++ b/include/linux/spi/spi.h
> @@ -764,6 +764,7 @@ extern void spi_unregister_controller(struct spi_controller *ctlr);
> extern struct spi_device *acpi_spi_device_alloc(struct spi_controller *ctlr,
> struct acpi_device *adev,
> int index);
> +int acpi_spi_count_resources(struct acpi_device *adev);
> #endif
>
> /*
>