ALSA: scarlett2: Allow passing any output to line_out_remap()

Line outputs 3 & 4 on the Gen 3 18i8 are internally the analogue 7 and
8 outputs, and this renumbering is hidden from the user by
line_out_remap(). By allowing higher values (representing non-analogue
outputs) to be passed to line_out_remap(), repeated code from
scarlett2_mux_src_enum_ctl_get() and scarlett2_mux_src_enum_ctl_put()
can be removed.

Signed-off-by: Geoffrey D. Bennett <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Takashi Iwai <[email protected]>

Author: geoffreybennett

sound/usb/mixer_scarlett2.c

@@ -2026,9 +2026,16 @@ static int scarlett2_master_volume_ctl_get(struct snd_kcontrol *kctl,
 static int line_out_remap(struct scarlett2_data *private, int index)
 {
 	const struct scarlett2_device_info *info = private->info;
+	const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
+	int line_out_count =
+		port_count[SCARLETT2_PORT_TYPE_ANALOGUE][SCARLETT2_PORT_OUT];
 
 	if (!info->line_out_remap_enable)
 		return index;
+
+	if (index >= line_out_count)
+		return index;
+
 	return info->line_out_remap[index];
 }
 
@@ -3513,14 +3520,7 @@ static int scarlett2_mux_src_enum_ctl_get(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 int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
-	int line_out_count =
-		port_count[SCARLETT2_PORT_TYPE_ANALOGUE][SCARLETT2_PORT_OUT];
-	int index = elem->control;
-
-	if (index < line_out_count)
-		index = line_out_remap(private, index);
+	int index = line_out_remap(private, elem->control);
 
 	mutex_lock(&private->data_mutex);
 	if (private->mux_updated)
@@ -3537,16 +3537,9 @@ static int scarlett2_mux_src_enum_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 int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
-	int line_out_count =
-		port_count[SCARLETT2_PORT_TYPE_ANALOGUE][SCARLETT2_PORT_OUT];
-	int index = elem->control;
+	int index = line_out_remap(private, elem->control);
 	int oval, val, err = 0;
 
-	if (index < line_out_count)
-		index = line_out_remap(private, index);
-
 	mutex_lock(&private->data_mutex);
 
 	oval = private->mux[index];