From: Christian Gromm Date: Mon, 17 Dec 2018 14:10:17 +0000 (+0100) Subject: staging: most: Documentation: add information to driver_usage file X-Git-Tag: v5.15~7300^2~27 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=d464b7dba1b82dce315af16de88cd6a866306b55;p=platform%2Fkernel%2Flinux-starfive.git staging: most: Documentation: add information to driver_usage file This patch updates driver_usage.txt file to reflect the latest changes that this patch set introduces. Signed-off-by: Christian Gromm Reviewed-by: Dan Carpenter Signed-off-by: Greg Kroah-Hartman --- 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 +The link names (most51_playback, most_playback and most_capture) will +become the names of the PCM devices of the sound card. Section 2.3 USB Padding