From 1ca8b201309d842642f221db7f02f71c0af5be2d Mon Sep 17 00:00:00 2001 From: Clemens Ladisch Date: Sun, 15 Nov 2015 22:38:29 +0100 Subject: ALSA: usb-audio: prevent CH345 multiport output SysEx corruption The CH345 USB MIDI chip has two output ports. However, they are multiplexed through one pin, and the number of ports cannot be reduced even for hardware that implements only one connector, so for those devices, data sent to either port ends up on the same hardware output. This becomes a problem when both ports are used at the same time, as longer MIDI commands (such as SysEx messages) are likely to be interrupted by messages from the other port, and thus to get lost. It would not be possible for the driver to detect how many ports the device actually has, except that in practice, _all_ devices built with the CH345 have only one port. So we can just ignore the device's descriptors, and hardcode one output port. Signed-off-by: Clemens Ladisch Cc: stable@vger.kernel.org Signed-off-by: Takashi Iwai --- sound/usb/quirks.c | 1 + 1 file changed, 1 insertion(+) (limited to 'sound/usb/quirks.c') diff --git a/sound/usb/quirks.c b/sound/usb/quirks.c index 5ca80e7d30cd..7016ad898187 100644 --- a/sound/usb/quirks.c +++ b/sound/usb/quirks.c @@ -538,6 +538,7 @@ int snd_usb_create_quirk(struct snd_usb_audio *chip, [QUIRK_MIDI_CME] = create_any_midi_quirk, [QUIRK_MIDI_AKAI] = create_any_midi_quirk, [QUIRK_MIDI_FTDI] = create_any_midi_quirk, + [QUIRK_MIDI_CH345] = create_any_midi_quirk, [QUIRK_AUDIO_STANDARD_INTERFACE] = create_standard_audio_quirk, [QUIRK_AUDIO_FIXED_ENDPOINT] = create_fixed_stream_quirk, [QUIRK_AUDIO_EDIROL_UAXX] = create_uaxx_quirk, -- cgit v1.2.3 From 12a6116e66695a728bcb9616416c508ce9c051a1 Mon Sep 17 00:00:00 2001 From: Anssi Hannula Date: Sun, 13 Dec 2015 20:49:59 +0200 Subject: ALSA: usb-audio: Add sample rate inquiry quirk for AudioQuest DragonFly Avoid getting sample rate on AudioQuest DragonFly as it is unsupported and causes noisy "cannot get freq at ep 0x1" messages when playback starts. Signed-off-by: Anssi Hannula Cc: Signed-off-by: Takashi Iwai --- sound/usb/quirks.c | 1 + 1 file changed, 1 insertion(+) (limited to 'sound/usb/quirks.c') diff --git a/sound/usb/quirks.c b/sound/usb/quirks.c index 7016ad898187..b6c0c8e3b450 100644 --- a/sound/usb/quirks.c +++ b/sound/usb/quirks.c @@ -1125,6 +1125,7 @@ bool snd_usb_get_sample_rate_quirk(struct snd_usb_audio *chip) case USB_ID(0x045E, 0x0779): /* MS Lifecam HD-3000 */ case USB_ID(0x04D8, 0xFEEA): /* Benchmark DAC1 Pre */ case USB_ID(0x074D, 0x3553): /* Outlaw RR2150 (Micronas UAC3553B) */ + case USB_ID(0x21B4, 0x0081): /* AudioQuest DragonFly */ return true; } return false; -- cgit v1.2.3