From 54852e8f401a70b3a0197737122be523639dc62f Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Mon, 12 Jun 2023 10:10:47 +0200 Subject: ALSA: usb-audio: Parse UMP Endpoint and Function Blocks at first 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. Link: https://lore.kernel.org/r/20230612081054.17200-4-tiwai@suse.de Signed-off-by: Takashi Iwai --- sound/usb/midi2.c | 34 +++++++++++++++++++++++++++++++++- 1 file changed, 33 insertions(+), 1 deletion(-) (limited to 'sound/usb') 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"); -- cgit