[alsa-devel] [PATCH] sound/usb: add dB range mapping for some devices.

[Yao-Wen Mao]

Add the correct dB ranges of Bose Companion 5 and Drangonfly DAC 1.2.

Signed-off-by: Yao-Wen Mao <yaowen at google.com>
---
 sound/usb/mixer_maps.c | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/sound/usb/mixer_maps.c b/sound/usb/mixer_maps.c
index e5000da..f0c9e49 100644
--- a/sound/usb/mixer_maps.c
+++ b/sound/usb/mixer_maps.c
@@ -339,6 +339,19 @@ static struct usbmix_name_map gamecom780_map[] = {
 static const struct usbmix_name_map scms_usb3318_map[] = {
 	{ 10, NULL },
 	{ 0 }
+
+/* Bose companion 5, the dB conversion factor is 16 instead of 256 */
+static struct usbmix_dB_map bose_companion5_dB = {-5006, -6};
+static struct usbmix_name_map bose_companion5_map[] = {
+	{ 3, NULL, .dB = &bose_companion5_dB },
+	{ 0 }	/* terminator */
+};
+
+/* Dragonfly DAC 1.2, the dB conversion factor is 1 instead of 256 */
+static struct usbmix_dB_map dragonfly_1_2_dB = {0, 5000};
+static struct usbmix_name_map dragonfly_1_2_map[] = {
+	{ 7, NULL, .dB = &dragonfly_1_2_dB },
+	{ 0 }	/* terminator */
 };
 
 /*
@@ -451,6 +464,16 @@ static struct usbmix_ctl_map usbmix_ctl_maps[] = {
 		.id = USB_ID(0x25c4, 0x0003),
 		.map = scms_usb3318_map,
 	},
+	{
+		/* Bose Companion 5 */
+		.id = USB_ID(0x05a7, 0x1020),
+		.map = bose_companion5_map,
+	},
+	{
+		/* Dragonfly DAC 1.2 */
+		.id = USB_ID(0x21b4, 0x0081),
+		.map = dragonfly_1_2_map,
+	},
 	{ 0 } /* terminator */
 };
 
-- 
2.5.0.rc2.392.g76e840b