ALSA: usb-audio: Add mode select quirk for Denon/Marantz DACs

Denon/Marantz USB DACs need a specific vendor command to switch between PCM and
DSD mode. This patch adds a new quirk function to switch between the two modes
using the specific USB vendor command.

This patch applies to the following devices:
- Marantz SA-14S1
- Marantz HD-DAC1

Signed-off-by: Jurgen Kramer <gtmkramer@xs4all.nl>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 5 insertions, 0 deletions

diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c
index c62a1659106d..0d8aba5fe1a8 100644
--- a/sound/usb/pcm.c
+++ b/sound/usb/pcm.c
@@ -482,6 +482,11 @@ static int set_format(struct snd_usb_substream *subs, struct audioformat *fmt)
         /* set interface */
         if (subs->interface != fmt->iface ||
             subs->altset_idx != fmt->altset_idx) {
+
+                err = snd_usb_select_mode_quirk(subs, fmt);
+                if (err < 0)
+                        return -EIO;
+
                 err = usb_set_interface(dev, fmt->iface, fmt->altsetting);
                 if (err < 0) {
                         dev_err(&dev->dev,