From: Thierry Reding treding@nvidia.com
By setting the MODALIAS variable in uevents, userspace helpers will be enabled to load modules via the module alias associated with a device.
This information is required to automatically load HDA codec drivers instead of having to explicitly request the various modules in the HDA core code.
[Note that currently the legacy HDA controller driver tries to bind codec modules manually. It's for supporting the fallback generic drivers. This new udev modalias support was added rather for ASoC HDA ext drivers, since this addition itself won't hurt the legacy HDA -- tiwai]
[Use the common helper function to generate the modalias -- tiwai]
Signed-off-by: Thierry Reding treding@nvidia.com Signed-off-by: Takashi Iwai tiwai@suse.de --- sound/hda/hda_bus_type.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)
diff --git a/sound/hda/hda_bus_type.c b/sound/hda/hda_bus_type.c index bcb1a79eec38..3060e2aee36f 100644 --- a/sound/hda/hda_bus_type.c +++ b/sound/hda/hda_bus_type.c @@ -64,9 +64,21 @@ static int hda_bus_match(struct device *dev, struct device_driver *drv) return 1; }
+static int hda_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + char modalias[32]; + + snd_hdac_codec_modalias(dev_to_hdac_dev(dev), modalias, + sizeof(modalias)); + if (add_uevent_var(env, "MODALIAS=%s", modalias)) + return -ENOMEM; + return 0; +} + struct bus_type snd_hda_bus_type = { .name = "hdaudio", .match = hda_bus_match, + .uevent = hda_uevent, }; EXPORT_SYMBOL_GPL(snd_hda_bus_type);