ALSA: usb-audio: Apply sample rate quirk for Audioengine D1
authorArvind Sankar <nivedita@alum.mit.edu>
Tue, 11 Feb 2020 16:22:35 +0000 (11:22 -0500)
committerTakashi Iwai <tiwai@suse.de>
Tue, 11 Feb 2020 19:13:28 +0000 (20:13 +0100)
commit93f9d1a4ac5930654c17412e3911b46ece73755a
treed1c99cd320eef38c11fb314b0da83dd7c8c6cdc3
parentd75a170fd848f037a1e28893ad10be7a4c51f8a6
ALSA: usb-audio: Apply sample rate quirk for Audioengine D1

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>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200211162235.1639889-1-nivedita@alum.mit.edu
Signed-off-by: Takashi Iwai <tiwai@suse.de>
sound/usb/quirks.c