On Thu, Dec 13, 2018 at 04:32:25PM +0000, Christian.Gromm@xxxxxxxxxxxxx wrote: > On Do, 2018-12-13 at 13:32 +0100, Greg KH wrote: > > On Thu, Dec 13, 2018 at 02:58:00PM +0300, Dan Carpenter wrote: > > > > > > On Wed, Dec 12, 2018 at 01:15:31PM +0100, Christian Gromm wrote: > > > > > > > > This patch updates driver_usage.txt file to reflect the latest > > > > changes > > > > that this patch set introduces. > > > > > > > > Signed-off-by: Christian Gromm <christian.gromm@xxxxxxxxxxxxx> > > > > --- > > > > drivers/staging/most/Documentation/driver_usage.txt | 16 > > > > +++++++++++++--- > > > > 1 file changed, 13 insertions(+), 3 deletions(-) > > > > > > > > diff --git a/drivers/staging/most/Documentation/driver_usage.txt > > > > b/drivers/staging/most/Documentation/driver_usage.txt > > > > index bb9b4e8..da7a8f4 100644 > > > > --- a/drivers/staging/most/Documentation/driver_usage.txt > > > > +++ b/drivers/staging/most/Documentation/driver_usage.txt > > > > @@ -142,8 +142,9 @@ Cdev component example: > > > > > > > > Sound component example: > > > > > > > > -The sound component needs an additional parameter to determine > > > > the audio > > > > -resolution that is going to be used. The following formats are > > > > available: > > > > +The sound component needs additional parameters to determine the > > > > audio > > > > +resolution that is going to be used and to trigger the > > > > registration of a > > > > +sound card with ALSA. The following audio formats are available: > > > > > > > > - "1x8" (Mono) > > > > - "2x16" (16-bit stereo) > > > > @@ -151,9 +152,18 @@ resolution that is going to be used. The > > > > following formats are available: > > > > - "2x32" (32-bit stereo) > > > > - "6x16" (16-bit surround 5.1) > > > > > > > > - $ echo "mdev0:ep_81:sound:most51_playback.6x16" > > > > >$(DRV_DIR)/add_link > > > > +To make the sound module create a sound card and register it > > > > with ALSA the > > > > +string "create" needs to be attached to the module parameter > > > > section of the > > > > +configuration string. To create a sound card with with two > > > > playback devices > > > > +(linked to channel ep01 and ep02) and one capture device (linked > > > > to channel > > > > +ep83) the following is written to the add_link file: > > > > > > > > + $ echo "mdev0:ep01:sound:most51_playback.6x16" > > > > >$(DRV_DIR)/add_link > > > > + $ echo "mdev0:ep02:sound:most_playback.2x16" > > > > >$(DRV_DIR)/add_link > > > > + $ echo "mdev0:ep83:sound:most_capture.2x16.create" > > > > >$(DRV_DIR)/add_link > > > I would maybe prefer if the "create" command were on a separate > > > line. > > > Something like: > > > > > > + $ echo "mdev0:ep01:sound:most51_playback.6x16" > > > >$(DRV_DIR)/add_link > > > + $ echo "mdev0:ep02:sound:most_playback.2x16" > > > >$(DRV_DIR)/add_link > > > + $ echo "mdev0:ep83:sound:most_capture.2x16" > > > >$(DRV_DIR)/add_link > > > + $ echo "mdev0:ep83:sound:create" >$(DRV_DIR)/sound_card > > > > > > It's sort of a separate command in a way? > > Why is sysfs being used for configuring things? Isn't that what > > configfs was created for? :) > > > > Omg, that would be one API change! > > I need to dig a little deeper into configfs to recognize > its beauty and the possible benefit for our driver. > > Do you see this as a prerequisite? Writing random strings to a random sysfs file to configure things is not a "normal" user/kernel api as sysfs files are supposed to just be "one value" and not parsed like what you are doing here. So I would strongly suggest looking at configfs, that is what it was designed for. thanks, greg k-h _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
