diff options
-rw-r--r-- | sound/usb/usbmidi.c | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/sound/usb/usbmidi.c b/sound/usb/usbmidi.c index 6e89b8368d9a..aae50df06232 100644 --- a/sound/usb/usbmidi.c +++ b/sound/usb/usbmidi.c @@ -1162,10 +1162,22 @@ static int snd_usbmidi_out_endpoint_create(struct snd_usb_midi* umidi, pipe = usb_sndintpipe(umidi->dev, ep_info->out_ep); else pipe = usb_sndbulkpipe(umidi->dev, ep_info->out_ep); - if (umidi->usb_id == USB_ID(0x0a92, 0x1020)) /* ESI M4U */ - ep->max_transfer = 4; - else + switch (umidi->usb_id) { + default: ep->max_transfer = usb_maxpacket(umidi->dev, pipe, 1); + break; + /* + * Various chips declare a packet size larger than 4 bytes, but + * do not actually work with larger packets: + */ + case USB_ID(0x0a92, 0x1020): /* ESI M4U */ + case USB_ID(0x1430, 0x474b): /* RedOctane GH MIDI INTERFACE */ + case USB_ID(0x15ca, 0x0101): /* Textech USB Midi Cable */ + case USB_ID(0x15ca, 0x1806): /* Textech USB Midi Cable */ + case USB_ID(0x1a86, 0x752d): /* QinHeng CH345 "USB2.0-MIDI" */ + ep->max_transfer = 4; + break; + } for (i = 0; i < OUTPUT_URBS; ++i) { buffer = usb_buffer_alloc(umidi->dev, ep->max_transfer, GFP_KERNEL, |