Re: [PATCH v4 1/3] ACPI / bus: Export acpi_of_modalias equiv of of_modalias_node

[Rafael J. Wysocki]

On Friday, January 27, 2017 01:30:13 PM Dan O'Donovan wrote:
> From: Crestez Dan Leonard <leonard.crestez@xxxxxxxxx>
> 
> When using devicetree stuff like i2c_client.name or spi_device.modalias
> is initialized to the first DT compatible id with the vendor prefix
> stripped. Since some drivers rely on this try to replicate it when using
> ACPI with DT ids.
> 
> Signed-off-by: Crestez Dan Leonard <leonard.crestez@xxxxxxxxx>
> Signed-off-by: Dan O'Donovan <dan@xxxxxxxxxx>
> Reviewed-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
> Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
> Reviewed-by: Jarkko Nikula <jarkko.nikula@xxxxxxxxxxxxxxx>
> Tested-by: Jarkko Nikula <jarkko.nikula@xxxxxxxxxxxxxxx>

First off, the original author of the patch doesn't seem to be reachable under
the Intel address any more, so his S-o-b is meaningless and it shouldn't be
there.  In such cases you can send the patch as From: you and give a credit
to the original author in the changelog.

Second, as Mark said ->

> ---
>  drivers/acpi/bus.c      | 35 +++++++++++++++++++++++++++++++++++
>  include/acpi/acpi_bus.h |  1 +
>  2 files changed, 36 insertions(+)
> 
> diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
> index 95855cb..8b9657f 100644
> --- a/drivers/acpi/bus.c
> +++ b/drivers/acpi/bus.c
> @@ -677,6 +677,41 @@ static bool acpi_of_match_device(struct acpi_device *adev,
>  	return false;
>  }
>  
> +/**
> + * acpi_of_modalias - Like of_modalias_node for ACPI with DT ids
> + * @adev:	ACPI device object to match.
> + * @outstr:	Pointer to buffer for result
> + * @outlen:	Length of outstr value
> + *
> + * This is a counterpart of of_modalias_node() for struct acpi_device
> + * objects. If there is a compatible string for @adev, copy it to the
> + * @outstr location with the vendor prefix stripped.
> + *
> + * Returns 0 on success or negative errno on failure.
> + */
> +int acpi_of_modalias(struct acpi_device *adev, char *outstr, size_t outlen)

-> this could be a bool function and you could provide something like
acpi_set_modalias() doing the entire

if (!acpi_of_modalias(adev, outstr, outlen))
               strlcpy(outstr, dev_name(&adev->dev), outlen);

thing, so that its users don't have to duplicate this conditional.

And then acpi_of_modalias() could be static and the only thing to export
would be acpi_set_modalias().

> +{
> +	const union acpi_object *of_compatible;
> +	const union acpi_object *obj;
> +	const char *str, *chr;
> +
> +	of_compatible = adev->data.of_compatible;
> +	if (!of_compatible)
> +		return -ENODEV;
> +
> +	if (of_compatible->type == ACPI_TYPE_PACKAGE)
> +		obj = of_compatible->package.elements;
> +	else /* Must be ACPI_TYPE_STRING. */
> +		obj = of_compatible;
> +
> +	str = obj->string.pointer;
> +	chr = strchr(str, ',');
> +	strlcpy(outstr, chr ? chr + 1 : str, outlen);
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(acpi_of_modalias);
> +
>  static bool __acpi_match_device_cls(const struct acpi_device_id *id,
>  				    struct acpi_hardware_id *hwid)
>  {
> diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
> index 4242c31..351b4a4 100644
> --- a/include/acpi/acpi_bus.h
> +++ b/include/acpi/acpi_bus.h
> @@ -522,6 +522,7 @@ void acpi_bus_trim(struct acpi_device *start);
>  acpi_status acpi_bus_get_ejd(acpi_handle handle, acpi_handle * ejd);
>  int acpi_match_device_ids(struct acpi_device *device,
>  			  const struct acpi_device_id *ids);
> +int acpi_of_modalias(struct acpi_device *adev, char *outstr, size_t outlen);
>  int acpi_create_dir(struct acpi_device *);
>  void acpi_remove_dir(struct acpi_device *);

Thanks,
Rafael