ALSA: usb-audio: add quirk to fix Hamedal C20 disconnect issue

For Hamedal C20, the current rate is different from the runtime rate,
snd_usb_endpoint stop and close endpoint to resetting rate.
if snd_usb_endpoint close the endpoint, sometimes usb will
disconnect the device.

Signed-off-by: Ai Chao <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Takashi Iwai <[email protected]>

Author: TomAi0

sound/usb/endpoint.c

@@ -931,7 +931,8 @@ void snd_usb_endpoint_close(struct snd_usb_audio *chip,
 	usb_audio_dbg(chip, "Closing EP 0x%x (count %d)\n",
 		      ep->ep_num, ep->opened);
 
-	if (!--ep->iface_ref->opened)
+	if (!--ep->iface_ref->opened &&
+		!(chip->quirk_flags & QUIRK_FLAG_IFACE_SKIP_CLOSE))
 		endpoint_set_interface(chip, ep, false);
 
 	if (!--ep->opened) {

sound/usb/quirks.c

@@ -2148,6 +2148,8 @@ static const struct usb_audio_quirk_flags_table quirk_flags_table[] = {
 		   QUIRK_FLAG_GENERIC_IMPLICIT_FB),
 	DEVICE_FLG(0x2b53, 0x0031, /* Fiero SC-01 (firmware v1.1.0) */
 		   QUIRK_FLAG_GENERIC_IMPLICIT_FB),
+	DEVICE_FLG(0x0525, 0xa4ad, /* Hamedal C20 usb camero */
+		   QUIRK_FLAG_IFACE_SKIP_CLOSE),
 
 	/* Vendor matches */
 	VENDOR_FLG(0x045e, /* MS Lifecam */

sound/usb/usbaudio.h

@@ -170,6 +170,8 @@ extern bool snd_usb_skip_validation;
  *  Apply the generic implicit feedback sync mode (same as implicit_fb=1 option)
  * QUIRK_FLAG_SKIP_IMPLICIT_FB
  *  Don't apply implicit feedback sync mode
+ * QUIRK_FLAG_IFACE_SKIP_CLOSE
+ *  Don't closed interface during setting sample rate
  */
 
 #define QUIRK_FLAG_GET_SAMPLE_RATE	(1U << 0)
@@ -191,5 +193,6 @@ extern bool snd_usb_skip_validation;
 #define QUIRK_FLAG_SET_IFACE_FIRST	(1U << 16)
 #define QUIRK_FLAG_GENERIC_IMPLICIT_FB	(1U << 17)
 #define QUIRK_FLAG_SKIP_IMPLICIT_FB	(1U << 18)
+#define QUIRK_FLAG_IFACE_SKIP_CLOSE	(1U << 19)
 
 #endif /* __USBAUDIO_H */