Re: [alsa-devel] [PATCH 06/14] soundwire: add support for sdw_slave_type

[Pierre-Louis Bossart]

On 11/3/19 12:32 AM, Vinod Koul wrote:
> On 23-10-19, 16:28, Pierre-Louis Bossart wrote:
> > Currently the bus does not have any explicit support for master
> > devices.  Add explicit support for sdw_slave_type, so that in
> > follow-up patches we can add support for the sdw_md_type (md==Master
> > Device), following the Grey Bus example.
> >
> > Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
> > ---
> >   drivers/soundwire/bus_type.c       | 9 ++++++++-
> >   drivers/soundwire/slave.c          | 7 ++++++-
> >   include/linux/soundwire/sdw_type.h | 6 ++++++
> >   3 files changed, 20 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/soundwire/bus_type.c b/drivers/soundwire/bus_type.c
> > index 9a0fd3ee1014..5df095f4e12f 100644
> > --- a/drivers/soundwire/bus_type.c
> > +++ b/drivers/soundwire/bus_type.c
> > @@ -49,9 +49,16 @@ int sdw_slave_modalias(const struct sdw_slave *slave, char *buf, size_t size)
> >   
> >   static int sdw_uevent(struct device *dev, struct kobj_uevent_env *env)
> >   {
> > -	struct sdw_slave *slave = to_sdw_slave_device(dev);
> > +	struct sdw_slave *slave;
> >   	char modalias[32];
> >   
> > +	if (is_sdw_slave(dev)) {
> > +		slave = to_sdw_slave_device(dev);
> > +	} else {
> > +		dev_warn(dev, "uevent for unknown Soundwire type\n");
> > +		return -EINVAL;
>
> when is the case where this would be triggered?

this is in preparation for the master case, where you will have 2 types 
of devices, so need to check if the type is correct.