[PATCH] ALSA: usb-audio: Apply sample rate quirk for Audioengine D1

[PATCH] ALSA: usb-audio: Apply sample rate quirk for Audioengine D1

[Arvind Sankar]

The Audioengine D1 (0x2912:0x30c8) does support reading the sample rate,
but it returns the rate in byte-reversed order.

When setting sampling rate, the driver produces these warning messages:
[168840.944226] usb 3-2.2: current rate 4500480 is different from the runtime rate 44100
[168854.930414] usb 3-2.2: current rate 8436480 is different from the runtime rate 48000
[168905.185825] usb 3-2.1.2: current rate 30465 is different from the runtime rate 96000

As can be seen from the hexadecimal conversion, the current rate read
back is byte-reversed from the rate that was set.

44100 == 0x00ac44, 4500480 == 0x44ac00
48000 == 0x00bb80, 8436480 == 0x80bb00
96000 == 0x017700,   30465 == 0x007701

Rather than implementing a new quirk to reverse the order, just skip
checking the rate to avoid spamming the log.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
---
 sound/usb/quirks.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/sound/usb/quirks.c b/sound/usb/quirks.c
index 3a5242e383b2..7f558f4b4520 100644
--- a/sound/usb/quirks.c
+++ b/sound/usb/quirks.c
@@ -1440,6 +1440,7 @@ bool snd_usb_get_sample_rate_quirk(struct snd_usb_audio *chip)
 	case USB_ID(0x1395, 0x740a): /* Sennheiser DECT */
 	case USB_ID(0x1901, 0x0191): /* GE B850V3 CP2114 audio interface */
 	case USB_ID(0x21b4, 0x0081): /* AudioQuest DragonFly */
+	case USB_ID(0x2912, 0x30c8): /* Audioengine D1 */
 		return true;
 	}
 
-- 
2.24.1

Re: [PATCH] ALSA: usb-audio: Apply sample rate quirk for Audioengine D1

[Takashi Iwai]

On Tue, 11 Feb 2020 17:22:35 +0100,
Arvind Sankar wrote:
> 
> The Audioengine D1 (0x2912:0x30c8) does support reading the sample rate,
> but it returns the rate in byte-reversed order.
> 
> When setting sampling rate, the driver produces these warning messages:
> [168840.944226] usb 3-2.2: current rate 4500480 is different from the runtime rate 44100
> [168854.930414] usb 3-2.2: current rate 8436480 is different from the runtime rate 48000
> [168905.185825] usb 3-2.1.2: current rate 30465 is different from the runtime rate 96000
> 
> As can be seen from the hexadecimal conversion, the current rate read
> back is byte-reversed from the rate that was set.
> 
> 44100 == 0x00ac44, 4500480 == 0x44ac00
> 48000 == 0x00bb80, 8436480 == 0x80bb00
> 96000 == 0x017700,   30465 == 0x007701
> 
> Rather than implementing a new quirk to reverse the order, just skip
> checking the rate to avoid spamming the log.
> 
> Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>

Thanks, applied now with Cc to stable.


Takashi