diff --git a/drivers/media/usb/em28xx/em28xx-cards.c b/drivers/media/usb/em28xx/em28xx-cards.c index 54e0362d8e3d..096206334134 100644 --- a/drivers/media/usb/em28xx/em28xx-cards.c +++ b/drivers/media/usb/em28xx/em28xx-cards.c @@ -3357,14 +3357,15 @@ static int em28xx_usb_probe(struct usb_interface *interface, dev->analog_ep_bulk = e->bEndpointAddress; } else { - has_dvb = true; if (usb_endpoint_xfer_isoc(e)) { dev->dvb_ep_isoc = e->bEndpointAddress; if (size > dev->dvb_max_pkt_size_isoc) { + has_dvb = true; /* see NOTE (~) */ dev->dvb_max_pkt_size_isoc = size; dev->dvb_alt_isoc = i; } } else { + has_dvb = true; dev->dvb_ep_bulk = e->bEndpointAddress; } } @@ -3391,6 +3392,12 @@ static int em28xx_usb_probe(struct usb_interface *interface, * so far. But there might be devices for which this * logic is not sufficient... */ + /* + * NOTE (~): some manufacturers (e.g. Terratec) disable + * endpoints by setting wMaxPacketSize to 0 bytes for + * all alt settings. So far, we've seen this for + * DVB isoc endpoints only. + */ } }