From c99f0802e42fcd38e84ee4d306691805ebed204f Mon Sep 17 00:00:00 2001
From: Jorge Sanjuan <jorge.sanjuan@codethink.co.uk>
Date: Fri, 11 May 2018 16:25:35 +0100
Subject: [PATCH] ALSA: usb-audio: Use Class Specific EP for UAC3 devices.
Git-commit: c99f0802e42fcd38e84ee4d306691805ebed204f
Patch-mainline: v4.17-rc6
References: bsc#1121278
bmAtributes offset doesn't exist in the UAC3 CS_EP descriptor.
Hence, checking for pitch control as if it was UAC2 doesn't make
any sense. Use the defined UAC3 offsets instead.
Fixes: 9a2fe9b801f5 ("ALSA: usb: initial USB Audio Device Class 3.0 support")
Signed-off-by: Jorge Sanjuan <jorge.sanjuan@codethink.co.uk>
Reviewed-by: Ruslan Bilovol <ruslan.bilovol@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
sound/usb/stream.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/sound/usb/stream.c b/sound/usb/stream.c
index 956be9f7c72a..5ed334575fc7 100644
--- a/sound/usb/stream.c
+++ b/sound/usb/stream.c
@@ -576,7 +576,7 @@ static int parse_uac_endpoint_attributes(struct snd_usb_audio *chip,
if (protocol == UAC_VERSION_1) {
attributes = csep->bmAttributes;
- } else {
+ } else if (protocol == UAC_VERSION_2) {
struct uac2_iso_endpoint_descriptor *csep2 =
(struct uac2_iso_endpoint_descriptor *) csep;
@@ -585,6 +585,13 @@ static int parse_uac_endpoint_attributes(struct snd_usb_audio *chip,
/* emulate the endpoint attributes of a v1 device */
if (csep2->bmControls & UAC2_CONTROL_PITCH)
attributes |= UAC_EP_CS_ATTR_PITCH_CONTROL;
+ } else { /* UAC_VERSION_3 */
+ struct uac3_iso_endpoint_descriptor *csep3 =
+ (struct uac3_iso_endpoint_descriptor *) csep;
+
+ /* emulate the endpoint attributes of a v1 device */
+ if (le32_to_cpu(csep3->bmControls) & UAC2_CONTROL_PITCH)
+ attributes |= UAC_EP_CS_ATTR_PITCH_CONTROL;
}
return attributes;
--
2.20.1