2020-05-26 06:29:01

by Chris Chiu

Subject: [PATCH] ALSA: usb: mixer: volume quirk for ESS Technology Asus USB DAC

The Asus USB DAC is a USB type-C audio dongle for connecting to
the headset and headphone. The volume minimum value -23040 which
is 0xa600 in hexadecimal with the resolution value 1 indicates
this should be endianness issue caused by the firmware bug. Add
a volume quirk to fix the volume control problem.

Also fixes this warning:
Warning! Unlikely big volume range (=23040), cval->res is probably wrong.
[5] FU [Headset Capture Volume] ch = 1, val = -23040/0/1
Warning! Unlikely big volume range (=23040), cval->res is probably wrong.
[7] FU [Headset Playback Volume] ch = 1, val = -23040/0/1

Signed-off-by: Chris Chiu <[email protected]>
---
sound/usb/mixer.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c
index 81b2db0edd5f..0b568a9fdab3 100644
--- a/sound/usb/mixer.c
+++ b/sound/usb/mixer.c
@@ -1171,6 +1171,14 @@ static void volume_control_quirks(struct usb_mixer_elem_info *cval,
cval->res = 384;
}
break;
+ case USB_ID(0x0495, 0x3042): /* ESS Technology Asus USB DAC */
+ if ((strstr(kctl->id.name, "Playback Volume") != NULL) ||
+ strstr(kctl->id.name, "Capture Volume") != NULL) {
+ cval->min >>= 8;
+ cval->max = 0;
+ cval->res = 1;
+ }
+ break;
}
}

--
2.20.1

2020-05-26 11:33:09

by Takashi Iwai

Subject: Re: [PATCH] ALSA: usb: mixer: volume quirk for ESS Technology Asus USB DAC

On Tue, 26 May 2020 08:26:13 +0200,
Chris Chiu wrote:
>
> The Asus USB DAC is a USB type-C audio dongle for connecting to
> the headset and headphone. The volume minimum value -23040 which
> is 0xa600 in hexadecimal with the resolution value 1 indicates
> this should be endianness issue caused by the firmware bug. Add
> a volume quirk to fix the volume control problem.
>
> Also fixes this warning:
> Warning! Unlikely big volume range (=23040), cval->res is probably wrong.
> [5] FU [Headset Capture Volume] ch = 1, val = -23040/0/1
> Warning! Unlikely big volume range (=23040), cval->res is probably wrong.
> [7] FU [Headset Playback Volume] ch = 1, val = -23040/0/1
>
> Signed-off-by: Chris Chiu <[email protected]>

Applied with Cc to stable now. Thanks.


Takashi