ALSA: usb-audio: Add mixer control for Digidesign Mbox 1 clock source

This patch provides the infrastructure for the Digidesign Mbox 1
to have a mixer control for selecting the clock source.
Valid options are Internal and S/PDIF external sync.
A non-documented command is sent to the device to enable this feature
found by reverse engineering and bus snooping.

Signed-off-by: Damien Zammit <damien@zamaudio.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/usb/mixer_maps.c b/sound/usb/mixer_maps.c
index d1d72ff..1994d41 100644 (file)
--- a/sound/usb/mixer_maps.c
+++ b/sound/usb/mixer_maps.c
@@ -179,6 +179,11 @@ static struct usbmix_name_map audigy2nx_map[] = {
        { 0 } /* terminator */
 };
 
+static struct usbmix_name_map mbox1_map[] = {
+       { 1, "Clock" },
+       { 0 } /* terminator */
+};
+
 static struct usbmix_selector_map c400_selectors[] = {
        {
                .id = 0x80,
@@ -415,6 +420,10 @@ static struct usbmix_ctl_map usbmix_ctl_maps[] = {
                .id = USB_ID(0x0ccd, 0x0028),
                .map = aureon_51_2_map,
        },
+       {
+               .id = USB_ID(0x0dba, 0x1000),
+               .map = mbox1_map,
+       },
        {
                .id = USB_ID(0x13e5, 0x0001),
                .map = scratch_live_map,

diff --git a/sound/usb/mixer_quirks.c b/sound/usb/mixer_quirks.c
index 3980bf5..4520316 100644 (file)
--- a/sound/usb/mixer_quirks.c
+++ b/sound/usb/mixer_quirks.c
@@ -565,6 +565,131 @@ static int snd_xonar_u1_controls_create(struct usb_mixer_interface *mixer)
        return 0;
 }
 
+/* Digidesign Mbox 1 clock source switch (internal/spdif) */
+
+static int snd_mbox1_switch_get(struct snd_kcontrol *kctl,
+                               struct snd_ctl_elem_value *ucontrol)
+{
+       ucontrol->value.enumerated.item[0] = kctl->private_value;
+       return 0;
+}
+
+static int snd_mbox1_switch_put(struct snd_kcontrol *kctl,
+                               struct snd_ctl_elem_value *ucontrol)
+{
+       struct snd_usb_audio *chip;
+       struct usb_mixer_interface *mixer;
+       int err;
+       bool cur_val, new_val;
+       unsigned char buff[3];
+
+       cur_val = kctl->private_value;
+       new_val = ucontrol->value.enumerated.item[0];
+
+       mixer = snd_kcontrol_chip(kctl);
+       if (snd_BUG_ON(!mixer))
+               return -EINVAL;
+
+       chip = mixer->chip;
+       if (snd_BUG_ON(!chip))
+               return -EINVAL;
+
+       if (cur_val == new_val)
+               return 0;
+
+       down_read(&chip->shutdown_rwsem);
+       if (chip->shutdown) {
+               err = -ENODEV;
+               goto err;
+       }
+
+       /* Prepare for magic command to toggle clock source */
+       err = snd_usb_ctl_msg(chip->dev,
+                               usb_rcvctrlpipe(chip->dev, 0), 0x81,
+                               USB_DIR_IN |
+                               USB_TYPE_CLASS |
+                               USB_RECIP_INTERFACE, 0x00, 0x500, buff, 1);
+       if (err < 0)
+               goto err;
+       err = snd_usb_ctl_msg(chip->dev,
+                               usb_rcvctrlpipe(chip->dev, 0), 0x81,
+                               USB_DIR_IN |
+                               USB_TYPE_CLASS |
+                               USB_RECIP_ENDPOINT, 0x100, 0x81, buff, 3);
+       if (err < 0)
+               goto err;
+
+       /* 2 possibilities:     Internal    -> send sample rate
+        *                      S/PDIF sync -> send zeroes
+        * NB: Sample rate locked to 48kHz on purpose to
+        *     prevent user from resetting the sample rate
+        *     while S/PDIF sync is enabled and confusing
+        *     this configuration.
+        */
+       if (new_val == 0) {
+               buff[0] = 0x80;
+               buff[1] = 0xbb;
+               buff[2] = 0x00;
+       } else {
+               buff[0] = buff[1] = buff[2] = 0x00;
+       }
+
+       /* Send the magic command to toggle the clock source */
+       err = snd_usb_ctl_msg(chip->dev,
+                               usb_sndctrlpipe(chip->dev, 0), 0x1,
+                               USB_TYPE_CLASS |
+                               USB_RECIP_ENDPOINT, 0x100, 0x81, buff, 3);
+       if (err < 0)
+               goto err;
+       err = snd_usb_ctl_msg(chip->dev,
+                               usb_rcvctrlpipe(chip->dev, 0), 0x81,
+                               USB_DIR_IN |
+                               USB_TYPE_CLASS |
+                               USB_RECIP_ENDPOINT, 0x100, 0x81, buff, 3);
+       if (err < 0)
+               goto err;
+       err = snd_usb_ctl_msg(chip->dev,
+                               usb_rcvctrlpipe(chip->dev, 0), 0x81,
+                               USB_DIR_IN |
+                               USB_TYPE_CLASS |
+                               USB_RECIP_ENDPOINT, 0x100, 0x2, buff, 3);
+       if (err < 0)
+               goto err;
+       kctl->private_value = new_val;
+
+err:
+       up_read(&chip->shutdown_rwsem);
+       return err < 0 ? err : 1;
+}
+
+static int snd_mbox1_switch_info(struct snd_kcontrol *kcontrol,
+                                struct snd_ctl_elem_info *uinfo)
+{
+       static const char *const texts[2] = {
+               "Internal",
+               "S/PDIF"
+       };
+
+       return snd_ctl_enum_info(uinfo, 1, ARRAY_SIZE(texts), texts);
+}
+
+static struct snd_kcontrol_new snd_mbox1_switch = {
+       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+       .name = "Clock Source",
+       .index = 0,
+       .access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
+       .info = snd_mbox1_switch_info,
+       .get = snd_mbox1_switch_get,
+       .put = snd_mbox1_switch_put,
+       .private_value = 0
+};
+
+static int snd_mbox1_create_sync_switch(struct usb_mixer_interface *mixer)
+{
+       return snd_ctl_add(mixer->chip->card,
+                       snd_ctl_new1(&snd_mbox1_switch, mixer));
+}
+
 /* Native Instruments device quirks */
 
 #define _MAKE_NI_CONTROL(bRequest,wIndex) ((bRequest) << 16 | (wIndex))
@@ -1632,6 +1757,10 @@ int snd_usb_mixer_apply_create_quirk(struct usb_mixer_interface *mixer)
                err = snd_microii_controls_create(mixer);
                break;
 
+       case USB_ID(0x0dba, 0x1000): /* Digidesign Mbox 1 */
+               err = snd_mbox1_create_sync_switch(mixer);
+               break;
+
        case USB_ID(0x17cc, 0x1011): /* Traktor Audio 6 */
                err = snd_nativeinstruments_create_mixer(mixer,
                                snd_nativeinstruments_ta6_mixers,