From: Takashi Iwai Date: Wed, 29 May 2024 16:47:17 +0000 (+0200) Subject: ALSA: ump: Set default protocol when not given explicitly X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=bc42ca002d5d211f9c57334b9b4c25ddb0b4ec35;p=linux.git ALSA: ump: Set default protocol when not given explicitly When an inquiry of the current protocol via UMP Stream Configuration message fails by some reason, we may leave the current protocol undefined, which may lead to unexpected behavior. Better to assume a valid protocol found in the protocol capability bits instead. For a device that doesn't support the UMP v1.2 feature, it won't reach to this code path, and USB MIDI GTB descriptor would be used for determining the protocol, instead. Link: https://lore.kernel.org/r/20240529164723.18309-2-tiwai@suse.de Signed-off-by: Takashi Iwai --- diff --git a/sound/core/ump.c b/sound/core/ump.c index 117c7ecc48563..3f61220c23b4e 100644 --- a/sound/core/ump.c +++ b/sound/core/ump.c @@ -967,6 +967,14 @@ int snd_ump_parse_endpoint(struct snd_ump_endpoint *ump) if (err < 0) ump_dbg(ump, "Unable to get UMP EP stream config\n"); + /* If no protocol is set by some reason, assume the valid one */ + if (!(ump->info.protocol & SNDRV_UMP_EP_INFO_PROTO_MIDI_MASK)) { + if (ump->info.protocol_caps & SNDRV_UMP_EP_INFO_PROTO_MIDI2) + ump->info.protocol |= SNDRV_UMP_EP_INFO_PROTO_MIDI2; + else if (ump->info.protocol_caps & SNDRV_UMP_EP_INFO_PROTO_MIDI1) + ump->info.protocol |= SNDRV_UMP_EP_INFO_PROTO_MIDI1; + } + /* Query and create blocks from Function Blocks */ for (blk = 0; blk < ump->info.num_blocks; blk++) { err = create_block_from_fb_info(ump, blk);