[PATCH v3] ALSA: usb-audio: Fix microphone sound on Jieli webcam.

[Marco Giunta]

When a Jieli Technology USB Webcam is connected, the video part works
well, but the mic sound is speeded up. On dmesg there are messages
about different rates from the runtime rates, warnings about volume
resolution and lastly, the log is filled, every 5 seconds, with
retire_capture_urb error messages.

The mic works only when ep packet size is set to wMaxPacketSize (normal
sound and no more retire_capture_urb error messages). Skipping reading
sample rate, fixes the messages about different rates and forcing a volume
resolution, fixes warnings about volume range. I have arbitrarily choosed
the value (16): I read in a comment that there should be no more than 255
levels, so 4096 (max volume) / 16 = 0-255.

Signed-off-by: Marco Giunta <giun7a at gmail.com>
---
 sound/usb/mixer.c  | 7 +++++++
 sound/usb/quirks.c | 7 +++++++
 2 files changed, 14 insertions(+)

diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c
index a2ce535..8e030b1 100644
--- a/sound/usb/mixer.c
+++ b/sound/usb/mixer.c
@@ -1198,6 +1198,13 @@ static void volume_control_quirks(struct usb_mixer_elem_info *cval,
 			cval->res = 1;
 		}
 		break;
+	case USB_ID(0x1224, 0x2a25): /* Jieli Technology USB PHY 2.0 */
+		if (!strcmp(kctl->id.name, "Mic Capture Volume")) {
+			usb_audio_info(chip,
+				"set resolution quirk: cval->res = 16\n");
+			cval->res = 16;
+		}
+		break;
 	}
 }
 
diff --git a/sound/usb/quirks.c b/sound/usb/quirks.c
index 889c855..712b699 100644
--- a/sound/usb/quirks.c
+++ b/sound/usb/quirks.c
@@ -1719,6 +1719,11 @@ void snd_usb_audioformat_attributes_quirk(struct snd_usb_audio *chip,
 		 */
 		fp->attributes &= ~UAC_EP_CS_ATTR_FILL_MAX;
 		break;
+	case USB_ID(0x1224, 0x2a25):  /* Jieli Technology USB PHY 2.0 */
+		/* mic works only when ep packet size is set to wMaxPacketSize */
+		fp->attributes |= UAC_EP_CS_ATTR_FILL_MAX;
+		break;
+
 	}
 }
 
@@ -1888,6 +1893,8 @@ static const struct usb_audio_quirk_flags_table quirk_flags_table[] = {
 		   QUIRK_FLAG_GET_SAMPLE_RATE),
 	DEVICE_FLG(0x534d, 0x2109, /* MacroSilicon MS2109 */
 		   QUIRK_FLAG_ALIGN_TRANSFER),
+	DEVICE_FLG(0x1224, 0x2a25, /* Jieli Technology USB PHY 2.0 */
+		   QUIRK_FLAG_GET_SAMPLE_RATE),
 
 	/* Vendor matches */
 	VENDOR_FLG(0x045e, /* MS Lifecam */
-- 
2.31.1