The USB audio device 0db0:cc78 (Realtek ALC4080) on the MSI MAG B850M
MORTAR WIFI motherboard exposes all playback controls as "PCM", which
makes it hard to tell the outputs apart.

Its mixer layout matches the one of the MSI MPG X570S Carbon Max Wifi
(units 29, 30 and 32), so reuse msi_mpg_x570s_carbon_max_wifi_alc4080_map
for this device too. With the mapping applied, the controls show up as
"Speaker", "Front Headphone" and "IEC958".

Tested with a patched snd-usb-audio module on a 7.2.7 kernel.

Signed-off-by: Tomasz Bojanowski <tomasz@bojanowski.me>
---
 sound/usb/mixer_maps.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/sound/usb/mixer_maps.c b/sound/usb/mixer_maps.c
index 41454cb40..f8e1f7803 100644
--- a/sound/usb/mixer_maps.c
+++ b/sound/usb/mixer_maps.c
@@ -749,6 +749,10 @@ static const struct usbmix_ctl_map usbmix_ctl_maps[] = {
 		.id = USB_ID(0x0db0, 0xa073),
 		.map = msi_mpg_x570s_carbon_max_wifi_alc4080_map,
 	},
+	{	/* MSI MAG B850M MORTAR WIFI */
+		.id = USB_ID(0x0db0, 0xcc78),
+		.map = msi_mpg_x570s_carbon_max_wifi_alc4080_map,
+	},
 	{	/* MSI TRX40 */
 		.id = USB_ID(0x0db0, 0x543d),
 		.map = trx40_mobo_map,
-- 
2.55.0