ALSA: scarlett2: Add input mute controls

Add controls for the input mute switches that the Vocaster interfaces
have. Mark scarlett2_notify_input_mute() as __always_unused until it
gets used when the Vocaster callback function array is added.
Signed-off-by: Geoffrey D. Bennett <g@b4.vu>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Message-ID: <3b384b4e759241bd06f0c223e9f4f00467d88318.1710264833.git.g@b4.vu>

sound/usb/mixer_scarlett2.c

@@ -85,7 +85,7 @@
  *    controls
  *  - disable/enable MSD mode
  *  - disable/enable standalone mode
- *  - input gain, autogain, safe mode
+ *  - input mute, gain, autogain, safe mode
  *  - direct monitor mixes
  *
  * <ditaa>
@@ -214,6 +214,7 @@ static const u16 scarlett2_mixer_values[SCARLETT2_MIXER_VALUE_COUNT] = {
 #define SCARLETT2_LEVEL_SWITCH_MAX 2
 #define SCARLETT2_PAD_SWITCH_MAX 8
 #define SCARLETT2_AIR_SWITCH_MAX 8
+#define SCARLETT2_INPUT_MUTE_SWITCH_MAX 2
 #define SCARLETT2_PHANTOM_SWITCH_MAX 2
 #define SCARLETT2_INPUT_GAIN_MAX 2
 
@@ -329,6 +330,7 @@ static void scarlett2_notify_volume(struct usb_mixer_interface *mixer);
 static void scarlett2_notify_input_level(struct usb_mixer_interface *mixer);
 static void scarlett2_notify_input_pad(struct usb_mixer_interface *mixer);
 static void scarlett2_notify_input_air(struct usb_mixer_interface *mixer);
+static void scarlett2_notify_input_mute(struct usb_mixer_interface *mixer);
 static void scarlett2_notify_input_phantom(struct usb_mixer_interface *mixer);
 static void scarlett2_notify_input_other(struct usb_mixer_interface *mixer);
 static void scarlett2_notify_input_select(struct usb_mixer_interface *mixer);
@@ -415,6 +417,7 @@ enum {
 	SCARLETT2_CONFIG_PAD_SWITCH,
 	SCARLETT2_CONFIG_MSD_SWITCH,
 	SCARLETT2_CONFIG_AIR_SWITCH,
+	SCARLETT2_CONFIG_INPUT_MUTE_SWITCH,
 	SCARLETT2_CONFIG_STANDALONE_SWITCH,
 	SCARLETT2_CONFIG_PHANTOM_SWITCH,
 	SCARLETT2_CONFIG_PHANTOM_PERSISTENCE,
@@ -915,6 +918,11 @@ struct scarlett2_device_info {
 	 */
 	u8 air_option;
 
+	/* the number of analogue inputs with a software switchable
+	 * mute control
+	 */
+	u8 mute_input_count;
+
 	/* the number of phantom (48V) software switchable controls */
 	u8 phantom_count;
 
@@ -996,6 +1004,7 @@ struct scarlett2_data {
 	u8 input_level_updated;
 	u8 input_pad_updated;
 	u8 input_air_updated;
+	u8 input_mute_updated;
 	u8 input_phantom_updated;
 	u8 input_select_updated;
 	u8 input_gain_updated;
@@ -1018,6 +1027,7 @@ struct scarlett2_data {
 	u8 pad_switch[SCARLETT2_PAD_SWITCH_MAX];
 	u8 dim_mute[SCARLETT2_DIM_MUTE_COUNT];
 	u8 air_switch[SCARLETT2_AIR_SWITCH_MAX];
+	u8 input_mute_switch[SCARLETT2_INPUT_MUTE_SWITCH_MAX];
 	u8 phantom_switch[SCARLETT2_PHANTOM_SWITCH_MAX];
 	u8 phantom_persistence;
 	u8 input_select_switch;
@@ -1045,6 +1055,7 @@ struct scarlett2_data {
 	struct snd_kcontrol *level_ctls[SCARLETT2_LEVEL_SWITCH_MAX];
 	struct snd_kcontrol *pad_ctls[SCARLETT2_PAD_SWITCH_MAX];
 	struct snd_kcontrol *air_ctls[SCARLETT2_AIR_SWITCH_MAX];
+	struct snd_kcontrol *input_mute_ctls[SCARLETT2_INPUT_MUTE_SWITCH_MAX];
 	struct snd_kcontrol *phantom_ctls[SCARLETT2_PHANTOM_SWITCH_MAX];
 	struct snd_kcontrol *input_select_ctl;
 	struct snd_kcontrol *input_link_ctls[SCARLETT2_INPUT_GAIN_MAX / 2];
@@ -2970,6 +2981,8 @@ static void scarlett2_autogain_update_access(struct usb_mixer_interface *mixer)
 		scarlett2_set_ctl_access(private->level_ctls[i], val);
 	for (i = 0; i < info->air_input_count; i++)
 		scarlett2_set_ctl_access(private->air_ctls[i], val);
+	for (i = 0; i < info->mute_input_count; i++)
+		scarlett2_set_ctl_access(private->input_mute_ctls[i], val);
 	for (i = 0; i < info->phantom_count; i++)
 		scarlett2_set_ctl_access(private->phantom_ctls[i], val);
 }
@@ -3005,6 +3018,9 @@ static void scarlett2_autogain_notify_access(struct usb_mixer_interface *mixer)
 	for (i = 0; i < info->air_input_count; i++)
 		snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO,
 			       &private->air_ctls[i]->id);
+	for (i = 0; i < info->mute_input_count; i++)
+		snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO,
+			       &private->input_mute_ctls[i]->id);
 	for (i = 0; i < info->phantom_count; i++)
 		snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO,
 			       &private->phantom_ctls[i]->id);
@@ -4619,6 +4635,100 @@ static const struct snd_kcontrol_new scarlett2_air_ctl[2] = {
 	}
 };
 
+/*** Input Mute Switch Controls ***/
+
+static int scarlett2_update_input_mute(struct usb_mixer_interface *mixer)
+{
+	struct scarlett2_data *private = mixer->private_data;
+	const struct scarlett2_device_info *info = private->info;
+
+	private->input_mute_updated = 0;
+
+	if (!info->mute_input_count)
+		return 0;
+
+	return scarlett2_usb_get_config(
+		mixer, SCARLETT2_CONFIG_INPUT_MUTE_SWITCH,
+		info->mute_input_count, private->input_mute_switch);
+}
+
+static int scarlett2_input_mute_ctl_get(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 err = 0;
+
+	mutex_lock(&private->data_mutex);
+
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
+	if (private->input_mute_updated) {
+		err = scarlett2_update_input_mute(mixer);
+		if (err < 0)
+			goto unlock;
+	}
+	ucontrol->value.integer.value[0] =
+		private->input_mute_switch[elem->control];
+
+unlock:
+	mutex_unlock(&private->data_mutex);
+	return err;
+}
+
+static int scarlett2_input_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;
+
+	mutex_lock(&private->data_mutex);
+
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
+	err = scarlett2_check_put_during_autogain(mixer);
+	if (err < 0)
+		goto unlock;
+
+	oval = private->input_mute_switch[index];
+	val = ucontrol->value.integer.value[0];
+
+	if (oval == val)
+		goto unlock;
+
+	private->input_mute_switch[index] = val;
+
+	/* Send switch change to the device */
+	err = scarlett2_usb_set_config(
+		mixer, SCARLETT2_CONFIG_INPUT_MUTE_SWITCH,
+			index, val);
+	if (err == 0)
+		err = 1;
+
+unlock:
+	mutex_unlock(&private->data_mutex);
+	return err;
+}
+
+static const struct snd_kcontrol_new scarlett2_input_mute_ctl = {
+	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+	.name = "",
+	.info = scarlett2_autogain_disables_ctl_info,
+	.get  = scarlett2_input_mute_ctl_get,
+	.put  = scarlett2_input_mute_ctl_put,
+};
+
 /*** Phantom Switch Controls ***/
 
 static int scarlett2_update_input_phantom(struct usb_mixer_interface *mixer)
@@ -5497,6 +5607,16 @@ static int scarlett2_add_line_in_ctls(struct usb_mixer_interface *mixer)
 			return err;
 	}
 
+	/* Add input mute controls */
+	for (i = 0; i < info->mute_input_count; i++) {
+		scnprintf(s, sizeof(s), fmt, i + 1, "Mute", "Switch");
+		err = scarlett2_add_new_ctl(
+			mixer, &scarlett2_input_mute_ctl,
+			i, 1, s, &private->input_mute_ctls[i]);
+		if (err < 0)
+			return err;
+	}
+
 	/* Add input phantom controls */
 	if (info->inputs_per_phantom == 1) {
 		for (i = 0; i < info->phantom_count; i++) {
@@ -6558,6 +6678,22 @@ static void scarlett2_notify_input_air(struct usb_mixer_interface *mixer)
 			       &private->air_ctls[i]->id);
 }
 
+/* Notify on input mute switch change */
+static __always_unused void scarlett2_notify_input_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;
+	int i;
+
+	private->input_mute_updated = 1;
+
+	for (i = 0; i < info->mute_input_count; i++)
+		snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
+			       &private->input_mute_ctls[i]->id);
+}
+
 /* Notify on input phantom switch change */
 static void scarlett2_notify_input_phantom(struct usb_mixer_interface *mixer)
 {
@@ -7171,6 +7307,10 @@ static int scarlett2_read_configs(struct usb_mixer_interface *mixer)
 	if (err < 0)
 		return err;
 
+	err = scarlett2_update_input_mute(mixer);
+	if (err < 0)
+		return err;
+
 	err = scarlett2_update_input_phantom(mixer);
 	if (err < 0)
 		return err;