ALSA: scarlett2: Split scarlett2_config_items[] into 3 sections

scarlett2_config_items[] contains the parameters for the configuration
items. The driver previously had two sets of configurations items; one
for devices with no mixer, and one for devices with a mixer. This
patch splits the latter into two (one set for Gen 2 devices and one
set for Gen 3 devices) in preparation for a new item (standalone)
which is present in both but with a different offset.
Signed-off-by: Geoffrey D. Bennett <g@b4.vu>
Link: https://lore.kernel.org/r/20969f9ea500684e978c87067fbdc7e73de1f6ed.1646578164.git.g@b4.vuSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/usb/mixer_scarlett_gen2.c

@@ -6,7 +6,7 @@
  *   - 6i6/18i8/18i20 Gen 2
  *   - Solo/2i2/4i4/8i6/18i8/18i20 Gen 3
  *
- *   Copyright (c) 2018-2021 by Geoffrey D. Bennett <g at b4.vu>
+ *   Copyright (c) 2018-2022 by Geoffrey D. Bennett <g at b4.vu>
  *   Copyright (c) 2020-2021 by Vladimir Sadovnikov <sadko4u@gmail.com>
  *
  *   Based on the Scarlett (Gen 1) Driver for ALSA:
@@ -195,6 +195,16 @@ static const u16 scarlett2_mixer_values[SCARLETT2_MIXER_VALUE_COUNT] = {
 /* Maximum number of meters (sum of output port counts) */
 #define SCARLETT2_MAX_METERS 65
 
+/* There are three different sets of configuration parameters across
+ * the devices
+ */
+enum {
+	SCARLETT2_CONFIG_SET_NO_MIXER = 0,
+	SCARLETT2_CONFIG_SET_GEN_2 = 1,
+	SCARLETT2_CONFIG_SET_GEN_3 = 2,
+	SCARLETT2_CONFIG_SET_COUNT = 3
+};
+
 /* Hardware port types:
  * - None (no input to mux)
  * - Analogue I/O
@@ -308,10 +318,8 @@ struct scarlett2_device_info {
 	 */
 	u8 has_msd_mode;
 
-	/* Gen 3 devices without a mixer have a different
-	 * configuration set
-	 */
-	u8 has_mixer;
+	/* which set of configuration parameters the device uses */
+	u8 config_set;
 
 	/* line out hw volume is sw controlled */
 	u8 line_out_hw_vol;
@@ -426,7 +434,7 @@ struct scarlett2_data {
 static const struct scarlett2_device_info s6i6_gen2_info = {
 	.usb_id = USB_ID(0x1235, 0x8203),
 
-	.has_mixer = 1,
+	.config_set = SCARLETT2_CONFIG_SET_GEN_2,
 	.level_input_count = 2,
 	.pad_input_count = 2,
 
@@ -472,7 +480,7 @@ static const struct scarlett2_device_info s6i6_gen2_info = {
 static const struct scarlett2_device_info s18i8_gen2_info = {
 	.usb_id = USB_ID(0x1235, 0x8204),
 
-	.has_mixer = 1,
+	.config_set = SCARLETT2_CONFIG_SET_GEN_2,
 	.level_input_count = 2,
 	.pad_input_count = 4,
 
@@ -521,7 +529,7 @@ static const struct scarlett2_device_info s18i8_gen2_info = {
 static const struct scarlett2_device_info s18i20_gen2_info = {
 	.usb_id = USB_ID(0x1235, 0x8201),
 
-	.has_mixer = 1,
+	.config_set = SCARLETT2_CONFIG_SET_GEN_2,
 	.line_out_hw_vol = 1,
 
 	.line_out_descrs = {
@@ -576,6 +584,7 @@ static const struct scarlett2_device_info solo_gen3_info = {
 	.usb_id = USB_ID(0x1235, 0x8211),
 
 	.has_msd_mode = 1,
+	.config_set = SCARLETT2_CONFIG_SET_NO_MIXER,
 	.level_input_count = 1,
 	.level_input_first = 1,
 	.air_input_count = 1,
@@ -588,6 +597,7 @@ static const struct scarlett2_device_info s2i2_gen3_info = {
 	.usb_id = USB_ID(0x1235, 0x8210),
 
 	.has_msd_mode = 1,
+	.config_set = SCARLETT2_CONFIG_SET_NO_MIXER,
 	.level_input_count = 2,
 	.air_input_count = 2,
 	.phantom_count = 1,
@@ -599,7 +609,7 @@ static const struct scarlett2_device_info s4i4_gen3_info = {
 	.usb_id = USB_ID(0x1235, 0x8212),
 
 	.has_msd_mode = 1,
-	.has_mixer = 1,
+	.config_set = SCARLETT2_CONFIG_SET_GEN_3,
 	.level_input_count = 2,
 	.pad_input_count = 2,
 	.air_input_count = 2,
@@ -645,7 +655,7 @@ static const struct scarlett2_device_info s8i6_gen3_info = {
 	.usb_id = USB_ID(0x1235, 0x8213),
 
 	.has_msd_mode = 1,
-	.has_mixer = 1,
+	.config_set = SCARLETT2_CONFIG_SET_GEN_3,
 	.level_input_count = 2,
 	.pad_input_count = 2,
 	.air_input_count = 2,
@@ -698,7 +708,7 @@ static const struct scarlett2_device_info s18i8_gen3_info = {
 	.usb_id = USB_ID(0x1235, 0x8214),
 
 	.has_msd_mode = 1,
-	.has_mixer = 1,
+	.config_set = SCARLETT2_CONFIG_SET_GEN_3,
 	.line_out_hw_vol = 1,
 	.has_speaker_switching = 1,
 	.level_input_count = 2,
@@ -768,7 +778,7 @@ static const struct scarlett2_device_info s18i20_gen3_info = {
 	.usb_id = USB_ID(0x1235, 0x8215),
 
 	.has_msd_mode = 1,
-	.has_mixer = 1,
+	.config_set = SCARLETT2_CONFIG_SET_GEN_3,
 	.line_out_hw_vol = 1,
 	.has_speaker_switching = 1,
 	.has_talkback = 1,
@@ -944,13 +954,11 @@ struct scarlett2_config {
 	u8 activate;
 };
 
-/* scarlett2_config_items[0] is for devices without a mixer
- * scarlett2_config_items[1] is for devices with a mixer
- */
 static const struct scarlett2_config
-	scarlett2_config_items[2][SCARLETT2_CONFIG_COUNT] =
+	scarlett2_config_items[SCARLETT2_CONFIG_SET_COUNT]
+			      [SCARLETT2_CONFIG_COUNT] =
 
-/* Devices without a mixer (Solo and 2i2 Gen 3) */
+/* Devices without a mixer (Gen 3 Solo and 2i2) */
 { {
 	[SCARLETT2_CONFIG_MSD_SWITCH] = {
 		.offset = 0x04, .size = 8, .activate = 6 },
@@ -970,7 +978,27 @@ static const struct scarlett2_config
 	[SCARLETT2_CONFIG_AIR_SWITCH] = {
 		.offset = 0x09, .size = 1, .activate = 8 },
 
-/* Devices with a mixer (Gen 2 and all other Gen 3) */
+/* Gen 2 devices: 6i6, 18i8, 18i20 */
+}, {
+	[SCARLETT2_CONFIG_DIM_MUTE] = {
+		.offset = 0x31, .size = 8, .activate = 2 },
+
+	[SCARLETT2_CONFIG_LINE_OUT_VOLUME] = {
+		.offset = 0x34, .size = 16, .activate = 1 },
+
+	[SCARLETT2_CONFIG_MUTE_SWITCH] = {
+		.offset = 0x5c, .size = 8, .activate = 1 },
+
+	[SCARLETT2_CONFIG_SW_HW_SWITCH] = {
+		.offset = 0x66, .size = 8, .activate = 3 },
+
+	[SCARLETT2_CONFIG_LEVEL_SWITCH] = {
+		.offset = 0x7c, .size = 8, .activate = 7 },
+
+	[SCARLETT2_CONFIG_PAD_SWITCH] = {
+		.offset = 0x84, .size = 8, .activate = 8 },
+
+/* Gen 3 devices: 4i4, 8i6, 18i8, 18i20 */
 }, {
 	[SCARLETT2_CONFIG_DIM_MUTE] = {
 		.offset = 0x31, .size = 8, .activate = 2 },
@@ -1175,7 +1203,7 @@ static int scarlett2_usb_get_config(
 	struct scarlett2_data *private = mixer->private_data;
 	const struct scarlett2_device_info *info = private->info;
 	const struct scarlett2_config *config_item =
-		&scarlett2_config_items[info->has_mixer][config_item_num];
+		&scarlett2_config_items[info->config_set][config_item_num];
 	int size, err, i;
 	u8 *buf_8;
 	u8 value;
@@ -1235,7 +1263,7 @@ static int scarlett2_usb_set_config(
 	struct scarlett2_data *private = mixer->private_data;
 	const struct scarlett2_device_info *info = private->info;
 	const struct scarlett2_config *config_item =
-	       &scarlett2_config_items[info->has_mixer][config_item_num];
+	       &scarlett2_config_items[info->config_set][config_item_num];
 	struct {
 		__le32 offset;
 		__le32 bytes;
@@ -1692,7 +1720,7 @@ static int scarlett2_add_sync_ctl(struct usb_mixer_interface *mixer)
 	struct scarlett2_data *private = mixer->private_data;
 
 	/* devices without a mixer also don't support reporting sync status */
-	if (!private->info->has_mixer)
+	if (private->info->config_set == SCARLETT2_CONFIG_SET_NO_MIXER)
 		return 0;
 
 	return scarlett2_add_new_ctl(mixer, &scarlett2_sync_ctl,
@@ -3399,7 +3427,7 @@ static int scarlett2_add_meter_ctl(struct usb_mixer_interface *mixer)
 	struct scarlett2_data *private = mixer->private_data;
 
 	/* devices without a mixer also don't support reporting levels */
-	if (!private->info->has_mixer)
+	if (private->info->config_set == SCARLETT2_CONFIG_SET_NO_MIXER)
 		return 0;
 
 	return scarlett2_add_new_ctl(mixer, &scarlett2_meter_ctl,
@@ -3632,7 +3660,7 @@ static int scarlett2_read_configs(struct usb_mixer_interface *mixer)
 		return err;
 
 	/* the rest of the configuration is for devices with a mixer */
-	if (!info->has_mixer)
+	if (info->config_set == SCARLETT2_CONFIG_SET_NO_MIXER)
 		return 0;
 
 	err = scarlett2_update_sync(mixer);