ALSA: usb-audio: scarlett2: Add mute support

For each analogue output, in addition to the output volume (gain)
control, the hardware also has a mute control. Add ALSA mute controls
for each analogue output.

If the device has the line_out_hw_vol feature, then the mute control
is disabled along with the output volume control when the switch is
set to HW.

Signed-off-by: Geoffrey D. Bennett <g@b4.vu>
Link: https://lore.kernel.org/r/6fad82174b44633e46cfd96332a038de74d544f2.1624294591.git.g@b4.vu
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/usb/mixer_scarlett_gen2.c b/sound/usb/mixer_scarlett_gen2.c
index e156119..d30f15d 100644 (file)
--- a/sound/usb/mixer_scarlett_gen2.c
+++ b/sound/usb/mixer_scarlett_gen2.c
@@ -39,7 +39,7 @@
  * This ALSA mixer gives access to:
  *  - input, output, mixer-matrix muxes
  *  - 18x10 mixer-matrix gain stages
- *  - gain/volume controls
+ *  - gain/volume/mute controls
  *  - level meters
  *  - line/inst level and pad controls
  *
@@ -195,7 +195,11 @@ enum {
 };
 
 /* Dim/Mute buttons on the 18i20 */
-#define SCARLETT2_DIM_MUTE_COUNT 2
+enum {
+       SCARLETT2_BUTTON_MUTE    = 0,
+       SCARLETT2_BUTTON_DIM     = 1,
+       SCARLETT2_DIM_MUTE_COUNT = 2,
+};
 
 static const char *const scarlett2_dim_mute_names[SCARLETT2_DIM_MUTE_COUNT] = {
        "Mute", "Dim"
@@ -258,12 +262,14 @@ struct scarlett2_data {
        u8 master_vol;
        u8 vol[SCARLETT2_ANALOGUE_MAX];
        u8 vol_sw_hw_switch[SCARLETT2_ANALOGUE_MAX];
+       u8 mute_switch[SCARLETT2_ANALOGUE_MAX];
        u8 level_switch[SCARLETT2_LEVEL_SWITCH_MAX];
        u8 pad_switch[SCARLETT2_PAD_SWITCH_MAX];
        u8 dim_mute[SCARLETT2_DIM_MUTE_COUNT];
        struct snd_kcontrol *sync_ctl;
        struct snd_kcontrol *master_vol_ctl;
        struct snd_kcontrol *vol_ctls[SCARLETT2_ANALOGUE_MAX];
+       struct snd_kcontrol *mute_ctls[SCARLETT2_ANALOGUE_MAX];
        struct snd_kcontrol *dim_mute_ctls[SCARLETT2_DIM_MUTE_COUNT];
        u8 mux[SCARLETT2_MUX_MAX];
        u8 mix[SCARLETT2_INPUT_MIX_MAX * SCARLETT2_OUTPUT_MIX_MAX];
@@ -509,7 +515,8 @@ struct scarlett2_usb_volume_status {
        /* actual volume of output inc. dim (-18dB) */
        s16 hw_vol[SCARLETT2_ANALOGUE_MAX];
 
-       u8 pad2[SCARLETT2_ANALOGUE_MAX];
+       /* internal mute buttons */
+       u8 mute_switch[SCARLETT2_ANALOGUE_MAX];
 
        /* sw (0) or hw (1) controlled */
        u8 sw_hw_switch[SCARLETT2_ANALOGUE_MAX];
@@ -524,10 +531,11 @@ struct scarlett2_usb_volume_status {
 enum {
        SCARLETT2_CONFIG_DIM_MUTE = 0,
        SCARLETT2_CONFIG_LINE_OUT_VOLUME = 1,
-       SCARLETT2_CONFIG_SW_HW_SWITCH = 2,
-       SCARLETT2_CONFIG_LEVEL_SWITCH = 3,
-       SCARLETT2_CONFIG_PAD_SWITCH = 4,
-       SCARLETT2_CONFIG_COUNT = 5
+       SCARLETT2_CONFIG_MUTE_SWITCH = 2,
+       SCARLETT2_CONFIG_SW_HW_SWITCH = 3,
+       SCARLETT2_CONFIG_LEVEL_SWITCH = 4,
+       SCARLETT2_CONFIG_PAD_SWITCH = 5,
+       SCARLETT2_CONFIG_COUNT = 6
 };
 
 /* Location, size, and activation command number for the configuration
@@ -547,6 +555,9 @@ static const struct scarlett2_config
        [SCARLETT2_CONFIG_LINE_OUT_VOLUME] = {
                .offset = 0x34, .size = 2, .activate = 1 },
 
+       [SCARLETT2_CONFIG_MUTE_SWITCH] = {
+               .offset = 0x5c, .size = 1, .activate = 1 },
+
        [SCARLETT2_CONFIG_SW_HW_SWITCH] = {
                .offset = 0x66, .size = 1, .activate = 3 },
 
@@ -1197,6 +1208,7 @@ static int scarlett2_update_volumes(struct usb_mixer_interface *mixer)
        int num_line_out =
                ports[SCARLETT2_PORT_TYPE_ANALOGUE].num[SCARLETT2_PORT_OUT];
        int err, i;
+       int mute;
 
        private->vol_updated = 0;
 
@@ -1208,15 +1220,18 @@ static int scarlett2_update_volumes(struct usb_mixer_interface *mixer)
                volume_status.master_vol + SCARLETT2_VOLUME_BIAS,
                0, SCARLETT2_VOLUME_BIAS);
 
-       for (i = 0; i < num_line_out; i++) {
-               if (private->vol_sw_hw_switch[i])
-                       private->vol[i] = private->master_vol;
-       }
-
        if (info->line_out_hw_vol)
                for (i = 0; i < SCARLETT2_DIM_MUTE_COUNT; i++)
                        private->dim_mute[i] = !!volume_status.dim_mute[i];
 
+       mute = private->dim_mute[SCARLETT2_BUTTON_MUTE];
+
+       for (i = 0; i < num_line_out; i++)
+               if (private->vol_sw_hw_switch[i]) {
+                       private->vol[i] = private->master_vol;
+                       private->mute_switch[i] = mute;
+               }
+
        return 0;
 }
 
@@ -1321,6 +1336,55 @@ static const struct snd_kcontrol_new scarlett2_line_out_volume_ctl = {
        .tlv = { .p = db_scale_scarlett2_gain }
 };
 
+/*** Mute Switch Controls ***/
+
+static int scarlett2_mute_ctl_get(struct snd_kcontrol *kctl,
+                                       struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct scarlett2_data *private = elem->head.mixer->private_data;
+       int index = elem->control;
+
+       ucontrol->value.integer.value[0] = private->mute_switch[index];
+       return 0;
+}
+
+static int scarlett2_mute_ctl_put(struct snd_kcontrol *kctl,
+                                       struct snd_ctl_elem_value *ucontrol)
+{
+       struct usb_mixer_elem_info *elem = kctl->private_data;
+       struct usb_mixer_interface *mixer = elem->head.mixer;
+       struct scarlett2_data *private = mixer->private_data;
+       int index = elem->control;
+       int oval, val, err = 0;
+
+       mutex_lock(&private->data_mutex);
+
+       oval = private->mute_switch[index];
+       val = !!ucontrol->value.integer.value[0];
+
+       if (oval == val)
+               goto unlock;
+
+       private->mute_switch[index] = val;
+
+       /* Send mute change to the device */
+       err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_MUTE_SWITCH,
+                                      index, val);
+
+unlock:
+       mutex_unlock(&private->data_mutex);
+       return err;
+}
+
+static const struct snd_kcontrol_new scarlett2_mute_ctl = {
+       .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+       .name = "",
+       .info = snd_ctl_boolean_mono_info,
+       .get  = scarlett2_mute_ctl_get,
+       .put  = scarlett2_mute_ctl_put,
+};
+
 /*** HW/SW Volume Switch Controls ***/
 
 static int scarlett2_sw_hw_enum_ctl_info(struct snd_kcontrol *kctl,
@@ -1348,18 +1412,26 @@ static void scarlett2_vol_ctl_set_writable(struct usb_mixer_interface *mixer,
                                           int index, int value)
 {
        struct scarlett2_data *private = mixer->private_data;
+       struct snd_card *card = mixer->chip->card;
 
-       /* Set/Clear write bit */
-       if (value)
+       /* Set/Clear write bits */
+       if (value) {
                private->vol_ctls[index]->vd[0].access |=
                        SNDRV_CTL_ELEM_ACCESS_WRITE;
-       else
+               private->mute_ctls[index]->vd[0].access |=
+                       SNDRV_CTL_ELEM_ACCESS_WRITE;
+       } else {
                private->vol_ctls[index]->vd[0].access &=
                        ~SNDRV_CTL_ELEM_ACCESS_WRITE;
+               private->mute_ctls[index]->vd[0].access &=
+                       ~SNDRV_CTL_ELEM_ACCESS_WRITE;
+       }
 
        /* Notify of write bit change */
-       snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_INFO,
+       snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO,
                       &private->vol_ctls[index]->id);
+       snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO,
+                      &private->mute_ctls[index]->id);
 }
 
 static int scarlett2_sw_hw_enum_ctl_put(struct snd_kcontrol *kctl,
@@ -1387,8 +1459,9 @@ static int scarlett2_sw_hw_enum_ctl_put(struct snd_kcontrol *kctl,
         */
        scarlett2_vol_ctl_set_writable(mixer, index, !val);
 
-       /* Reset volume to master volume */
+       /* Reset volume/mute to master volume/mute */
        private->vol[index] = private->master_vol;
+       private->mute_switch[index] = private->dim_mute[SCARLETT2_BUTTON_MUTE];
 
        /* Set SW volume to current HW volume */
        err = scarlett2_usb_set_config(
@@ -1397,6 +1470,13 @@ static int scarlett2_sw_hw_enum_ctl_put(struct snd_kcontrol *kctl,
        if (err < 0)
                goto unlock;
 
+       /* Set SW mute to current HW mute */
+       err = scarlett2_usb_set_config(
+               mixer, SCARLETT2_CONFIG_MUTE_SWITCH,
+               index, private->dim_mute[SCARLETT2_BUTTON_MUTE]);
+       if (err < 0)
+               goto unlock;
+
        /* Send SW/HW switch change to the device */
        err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_SW_HW_SWITCH,
                                       index, val);
@@ -1554,9 +1634,13 @@ static int scarlett2_dim_mute_ctl_put(struct snd_kcontrol *kctl,
        struct usb_mixer_elem_info *elem = kctl->private_data;
        struct usb_mixer_interface *mixer = elem->head.mixer;
        struct scarlett2_data *private = mixer->private_data;
+       const struct scarlett2_device_info *info = private->info;
+       const struct scarlett2_ports *ports = info->ports;
+       int num_line_out =
+               ports[SCARLETT2_PORT_TYPE_ANALOGUE].num[SCARLETT2_PORT_OUT];
 
        int index = elem->control;
-       int oval, val, err = 0;
+       int oval, val, err = 0, i;
 
        mutex_lock(&private->data_mutex);
 
@@ -1574,6 +1658,15 @@ static int scarlett2_dim_mute_ctl_put(struct snd_kcontrol *kctl,
        if (err == 0)
                err = 1;
 
+       if (index == SCARLETT2_BUTTON_MUTE)
+               for (i = 0; i < num_line_out; i++)
+                       if (private->vol_sw_hw_switch[i]) {
+                               private->mute_switch[i] = val;
+                               snd_ctl_notify(mixer->chip->card,
+                                              SNDRV_CTL_EVENT_MASK_INFO,
+                                              &private->mute_ctls[i]->id);
+                       }
+
 unlock:
        mutex_unlock(&private->data_mutex);
        return err;
@@ -1627,7 +1720,20 @@ static int scarlett2_add_line_out_ctls(struct usb_mixer_interface *mixer)
                if (err < 0)
                        return err;
 
-               /* Make the fader read-only if the SW/HW switch is set to HW */
+               /* Mute Switch */
+               snprintf(s, sizeof(s),
+                        "Line %02d Mute Playback Switch",
+                        i + 1);
+               err = scarlett2_add_new_ctl(mixer,
+                                           &scarlett2_mute_ctl,
+                                           i, 1, s,
+                                           &private->mute_ctls[i]);
+               if (err < 0)
+                       return err;
+
+               /* Make the fader and mute controls read-only if the
+                * SW/HW switch is set to HW
+                */
                if (private->vol_sw_hw_switch[i])
                        scarlett2_vol_ctl_set_writable(mixer, i, 0);
 
@@ -2109,12 +2215,16 @@ static int scarlett2_read_configs(struct usb_mixer_interface *mixer)
        if (err < 0)
                return err;
 
+       if (info->line_out_hw_vol)
+               for (i = 0; i < SCARLETT2_DIM_MUTE_COUNT; i++)
+                       private->dim_mute[i] = !!volume_status.dim_mute[i];
+
        private->master_vol = clamp(
                volume_status.master_vol + SCARLETT2_VOLUME_BIAS,
                0, SCARLETT2_VOLUME_BIAS);
 
        for (i = 0; i < num_line_out; i++) {
-               int volume;
+               int volume, mute;
 
                private->vol_sw_hw_switch[i] =
                        info->line_out_hw_vol
@@ -2126,11 +2236,12 @@ static int scarlett2_read_configs(struct usb_mixer_interface *mixer)
                volume = clamp(volume + SCARLETT2_VOLUME_BIAS,
                               0, SCARLETT2_VOLUME_BIAS);
                private->vol[i] = volume;
-       }
 
-       if (info->line_out_hw_vol)
-               for (i = 0; i < SCARLETT2_DIM_MUTE_COUNT; i++)
-                       private->dim_mute[i] = !!volume_status.dim_mute[i];
+               mute = private->vol_sw_hw_switch[i]
+                        ? private->dim_mute[SCARLETT2_BUTTON_MUTE]
+                        : volume_status.mute_switch[i];
+               private->mute_switch[i] = mute;
+       }
 
        for (i = 0; i < num_mixer_out; i++) {
                err = scarlett2_usb_get_mix(mixer, i);
@@ -2185,8 +2296,12 @@ static void scarlett2_notify_monitor(
 static void scarlett2_notify_dim_mute(
        struct usb_mixer_interface *mixer)
 {
+       struct snd_card *card = mixer->chip->card;
        struct scarlett2_data *private = mixer->private_data;
        const struct scarlett2_device_info *info = private->info;
+       const struct scarlett2_ports *ports = info->ports;
+       int num_line_out =
+               ports[SCARLETT2_PORT_TYPE_ANALOGUE].num[SCARLETT2_PORT_OUT];
        int i;
 
        private->vol_updated = 1;
@@ -2195,8 +2310,13 @@ static void scarlett2_notify_dim_mute(
                return;
 
        for (i = 0; i < SCARLETT2_DIM_MUTE_COUNT; i++)
-               snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
+               snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
                               &private->dim_mute_ctls[i]->id);
+
+       for (i = 0; i < num_line_out; i++)
+               if (private->vol_sw_hw_switch[i])
+                       snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
+                                      &private->mute_ctls[i]->id);
 }
 
 /* Interrupt callback */