[PATCH v2] ALSA: usb-audio: Add quirk for Focusrite Scarlett 2i2

Gregor Pintar grpintar at gmail.com
Mon Apr 20 23:40:30 CEST 2020


Force it to use asynchronous playback.

Same quirk has already been added for Focusrite Scarlett Solo (2nd gen)
with a commit 46f5710f0b88 ("ALSA: usb-audio: Add quirk for Focusrite
Scarlett Solo").

This also seems to prevent regular clicks when playing at 44100Hz
on Scarlett 2i2 (2nd gen). I did not notice any side effects.

Moved both quirks to snd_usb_audioformat_attributes_quirk() as suggested.

Signed-off-by: Gregor Pintar <grpintar at gmail.com>
---
 sound/usb/quirks-table.h | 84 ----------------------------------------
 sound/usb/quirks.c       | 13 +++++++
 2 files changed, 13 insertions(+), 84 deletions(-)

diff --git a/sound/usb/quirks-table.h b/sound/usb/quirks-table.h
index e009d584e..7e06ab108 100644
--- a/sound/usb/quirks-table.h
+++ b/sound/usb/quirks-table.h
@@ -2756,90 +2756,6 @@ YAMAHA_DEVICE(0x7010, "UB99"),
 		.type = QUIRK_MIDI_NOVATION
 	}
 },
-{
-	/*
-	 * Focusrite Scarlett Solo 2nd generation
-	 * Reports that playback should use Synch: Synchronous
-	 * while still providing a feedback endpoint. Synchronous causes
-	 * snapping on some sample rates.
-	 * Force it to use Synch: Asynchronous.
-	 */
-	USB_DEVICE(0x1235, 0x8205),
-	.driver_info = (unsigned long) & (const struct snd_usb_audio_quirk) {
-		.ifnum = QUIRK_ANY_INTERFACE,
-		.type = QUIRK_COMPOSITE,
-		.data = (const struct snd_usb_audio_quirk[]) {
-			{
-				.ifnum = 1,
-				.type = QUIRK_AUDIO_FIXED_ENDPOINT,
-				.data = & (const struct audioformat) {
-					.formats = SNDRV_PCM_FMTBIT_S32_LE,
-					.channels = 2,
-					.iface = 1,
-					.altsetting = 1,
-					.altset_idx = 1,
-					.attributes = 0,
-					.endpoint = 0x01,
-					.ep_attr = USB_ENDPOINT_XFER_ISOC |
-						   USB_ENDPOINT_SYNC_ASYNC,
-					.protocol = UAC_VERSION_2,
-					.rates = SNDRV_PCM_RATE_44100 |
-						 SNDRV_PCM_RATE_48000 |
-						 SNDRV_PCM_RATE_88200 |
-						 SNDRV_PCM_RATE_96000 |
-						 SNDRV_PCM_RATE_176400 |
-						 SNDRV_PCM_RATE_192000,
-					.rate_min = 44100,
-					.rate_max = 192000,
-					.nr_rates = 6,
-					.rate_table = (unsigned int[]) {
-						44100, 48000, 88200,
-						96000, 176400, 192000
-					},
-					.clock = 41
-				}
-			},
-			{
-				.ifnum = 2,
-				.type = QUIRK_AUDIO_FIXED_ENDPOINT,
-				.data = & (const struct audioformat) {
-					.formats = SNDRV_PCM_FMTBIT_S32_LE,
-					.channels = 2,
-					.iface = 2,
-					.altsetting = 1,
-					.altset_idx = 1,
-					.attributes = 0,
-					.endpoint = 0x82,
-					.ep_attr = USB_ENDPOINT_XFER_ISOC |
-						   USB_ENDPOINT_SYNC_ASYNC |
-						   USB_ENDPOINT_USAGE_IMPLICIT_FB,
-					.protocol = UAC_VERSION_2,
-					.rates = SNDRV_PCM_RATE_44100 |
-						 SNDRV_PCM_RATE_48000 |
-						 SNDRV_PCM_RATE_88200 |
-						 SNDRV_PCM_RATE_96000 |
-						 SNDRV_PCM_RATE_176400 |
-						 SNDRV_PCM_RATE_192000,
-					.rate_min = 44100,
-					.rate_max = 192000,
-					.nr_rates = 6,
-					.rate_table = (unsigned int[]) {
-						44100, 48000, 88200,
-						96000, 176400, 192000
-					},
-					.clock = 41
-				}
-			},
-			{
-				.ifnum = 3,
-				.type = QUIRK_IGNORE_INTERFACE
-			},
-			{
-				.ifnum = -1
-			}
-		}
-	}
-},
 
 /* Access Music devices */
 {
diff --git a/sound/usb/quirks.c b/sound/usb/quirks.c
index a8ece1701..6c2dfd3bf 100644
--- a/sound/usb/quirks.c
+++ b/sound/usb/quirks.c
@@ -1806,6 +1806,19 @@ void snd_usb_audioformat_attributes_quirk(struct snd_usb_audio *chip,
 		 */
 		fp->attributes &= ~UAC_EP_CS_ATTR_FILL_MAX;
 		break;
+	case USB_ID(0x1235, 0x8202):  /* Focusrite Scarlett 2i2 2nd gen */
+	case USB_ID(0x1235, 0x8205):  /* Focusrite Scarlett Solo 2nd gen */
+		/*
+		 * Reports that playback should use Synch: Synchronous
+		 * while still providing a feedback endpoint.
+		 * Synchronous causes snapping on some sample rates.
+		 * Force it to use Synch: Asynchronous.
+		 */
+		if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
+			fp->ep_attr &= ~USB_ENDPOINT_SYNCTYPE;
+			fp->ep_attr |= USB_ENDPOINT_SYNC_ASYNC;
+		}
+		break;
 	}
 }
 
-- 
2.20.1



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