Try to parse the UMP Endpoint and UMP Function Blocks for building the topology at first. Only when those are missing (e.g. on an older USB MIDI 2.0 spec or a unidirectional endpoint), the driver still creates blocks based on USB group terminal block information as fallback. Signed-off-by: Takashi Iwai <tiwai@xxxxxxx> --- sound/usb/midi2.c | 34 +++++++++++++++++++++++++++++++++- 1 file changed, 33 insertions(+), 1 deletion(-) diff --git a/sound/usb/midi2.c b/sound/usb/midi2.c index 341783418a6a..fad094e15999 100644 --- a/sound/usb/midi2.c +++ b/sound/usb/midi2.c @@ -80,6 +80,7 @@ struct snd_usb_midi2_ump { struct snd_usb_midi2_endpoint *eps[2]; /* USB MIDI endpoints */ int index; /* rawmidi device index */ unsigned char usb_block_id; /* USB GTB id used for finding a pair */ + bool ump_parsed; /* Parsed UMP 1.1 EP/FB info*/ struct list_head list; /* list to umidi->rawmidi_list */ }; @@ -786,6 +787,31 @@ static int find_matching_ep_partner(struct snd_usb_midi2_interface *umidi, return 0; } +/* Call UMP helper to parse UMP endpoints; + * this needs to be called after starting the input streams for bi-directional + * communications + */ +static int parse_ump_endpoints(struct snd_usb_midi2_interface *umidi) +{ + struct snd_usb_midi2_ump *rmidi; + int err; + + list_for_each_entry(rmidi, &umidi->rawmidi_list, list) { + if (!rmidi->ump || + !(rmidi->ump->core.info_flags & SNDRV_RAWMIDI_INFO_DUPLEX)) + continue; + err = snd_ump_parse_endpoint(rmidi->ump); + if (!err) { + rmidi->ump_parsed = true; + } else { + if (err == -ENOMEM) + return err; + /* fall back to GTB later */ + } + } + return 0; +} + /* create a UMP block from a GTB entry */ static int create_gtb_block(struct snd_usb_midi2_ump *rmidi, int dir, int blk) { @@ -856,7 +882,7 @@ static int create_blocks_from_gtb(struct snd_usb_midi2_interface *umidi) if (!rmidi->ump) continue; /* Blocks have been already created? */ - if (rmidi->ump->info.num_blocks) + if (rmidi->ump_parsed || rmidi->ump->info.num_blocks) continue; /* loop over GTBs */ for (dir = 0; dir < 2; dir++) { @@ -1110,6 +1136,12 @@ int snd_usb_midi_v2_create(struct snd_usb_audio *chip, goto error; } + err = parse_ump_endpoints(umidi); + if (err < 0) { + usb_audio_err(chip, "Failed to parse UMP endpoint\n"); + goto error; + } + err = create_blocks_from_gtb(umidi); if (err < 0) { usb_audio_err(chip, "Failed to create GTB blocks\n"); -- 2.35.3