Merge tag 'sound-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound

Pull sound updates from Takashi Iwai:
 "This one became bigger than usual, not in the total size but rather
  containing lots of small changes all over the places.

  The majority of changes are about ASoC, especially SOF / Intel stuff,
  and we see an interesting work for ASoC DAPM graph visualization,
  while there are many other code cleanup and refactoring, too.

  Core:
   - A deadlock fix at device disconnection
   - A new tool dapm-graph for visualising the DAPM state

  ASoC:
   - Large updates throughout the Intel audio drivers
   - Fixes and clarifications for the DAPM documentation
   - Cleanups of accessors for driver data, module labelling, and for
     constification
   - Modernsation and cleanup work in the Mediatek drivers
   - Several fixes and features for the DaVinci I2S driver
   - New drivers for several AMD and Intel platforms, Nuvoton NAU8325,
     Rockchip RK3308 and Texas Instruments PCM6240

  HD-audio:
   - Cleanup for CONFIG_PM dependencies
   - Cirrus HD-audio codec fixes and quirks

  Others:
   - Series of tree-wide fixes in Makefiles to use *-y
   - Additions of missing module descriptions
   - Scarlett2 USB mixer enhancements
   - A series of legacy emu10k1 fixes and improvements"

* tag 'sound-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (603 commits)
  ALSA: hda/realtek: Drop doubly quirk entry for 103c:8a2e
  ALSA: hda/realtek - fixed headset Mic not show
  ASoC: SOF: amd: Fix build error with built-in config
  ALSA: scarlett2: Increase mixer range to +12dB
  ALSA: scarlett2: Add S/PDIF source selection controls
  ALSA: core: Remove superfluous CONFIG_PM
  ALSA: Fix deadlocks with kctl removals at disconnection
  ASoC: audio-graph-card2: call of_node_get() before of_get_next_child()
  ASoC: SOF: amd: Correct spaces in Makefile
  ASoC: rt715-sdca-sdw: Fix wrong complete waiting in rt715_dev_resume()
  ASoC: Intel: sof_sdw_rt_amp: use dai parameter
  ASoC: Intel: sof_sdw: add dai parameter to rtd_init callback
  ASoC: Intel: sof_sdw: use .controls/.widgets to add controls/widgets
  ASoC: Intel: sof_sdw: add controls and dapm widgets in codec_info
  ASoC: Intel: sof_sdw: use generic name for controls/widgets
  ASoC: Intel: sof_sdw_cs_amp: rename Speakers to Speaker
  ASoC: Intel: maxim-common: change max98373 data to static
  ASoC: Intel: sof_sdw: add max98373 dapm routes
  ASoC: Intel: sof_rt5682: use max_98373_dai_link function
  ASoC: Intel: sof_nau8825: use max_98373_dai_link function
  ...

1 files changed, 2366 insertions, 477 deletions

diff --git a/sound/usb/mixer_scarlett2.c b/sound/usb/mixer_scarlett2.c
index bd114be537d7..1150cf104985 100644
--- a/sound/usb/mixer_scarlett2.c
+++ b/sound/usb/mixer_scarlett2.c
@@ -85,8 +85,10 @@
  *    controls
  *  - disable/enable MSD mode
  *  - disable/enable standalone mode
- *  - input gain, autogain, safe mode
+ *  - input mute, gain, autogain, safe mode
  *  - direct monitor mixes
+ *  - compressor and EQ
+ *  - Bluetooth volume
  *
  * <ditaa>
  *    /--------------\    18chn            20chn     /--------------\
@@ -174,22 +176,24 @@
 /* some gui mixers can't handle negative ctl values */
 #define SCARLETT2_VOLUME_BIAS 127
 
-/* maximum preamp input gain and value
- * values are from 0 to 70, preamp gain is from 0 to 69 dB
+/* maximum preamp input gain value
+ * (the corresponding value in dB is per-device)
  */
 #define SCARLETT2_MAX_GAIN_VALUE 70
-#define SCARLETT2_MAX_GAIN_DB 69
 
-/* mixer range from -80dB to +6dB in 0.5dB steps */
+/* maximum Bluetooth volume value */
+#define SCARLETT2_MAX_BLUETOOTH_VOLUME 30
+
+/* mixer range from -80dB to +12dB in 0.5dB steps */
 #define SCARLETT2_MIXER_MIN_DB -80
 #define SCARLETT2_MIXER_BIAS (-SCARLETT2_MIXER_MIN_DB * 2)
-#define SCARLETT2_MIXER_MAX_DB 6
+#define SCARLETT2_MIXER_MAX_DB 12
 #define SCARLETT2_MIXER_MAX_VALUE \
 	((SCARLETT2_MIXER_MAX_DB - SCARLETT2_MIXER_MIN_DB) * 2)
 #define SCARLETT2_MIXER_VALUE_COUNT (SCARLETT2_MIXER_MAX_VALUE + 1)
 
 /* map from (dB + 80) * 2 to mixer value
- * for dB in 0 .. 172: int(8192 * pow(10, ((dB - 160) / 2 / 20)))
+ * for dB in 0 .. 184: int(8192 * pow(10, ((dB - 160) / 2 / 20)))
  */
 static const u16 scarlett2_mixer_values[SCARLETT2_MIXER_VALUE_COUNT] = {
 	0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2,
@@ -205,7 +209,8 @@ static const u16 scarlett2_mixer_values[SCARLETT2_MIXER_VALUE_COUNT] = {
 	3078, 3261, 3454, 3659, 3876, 4105, 4349, 4606, 4879, 5168,
 	5475, 5799, 6143, 6507, 6892, 7301, 7733, 8192, 8677, 9191,
 	9736, 10313, 10924, 11571, 12257, 12983, 13752, 14567, 15430,
-	16345
+	16345, 17313, 18339, 19426, 20577, 21796, 23088, 24456, 25905,
+	27440, 29066, 30788, 32612
 };
 
 /* Maximum number of analogue outputs */
@@ -215,6 +220,8 @@ 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_DSP_SWITCH_MAX 2
+#define SCARLETT2_INPUT_MUTE_SWITCH_MAX 2
 #define SCARLETT2_PHANTOM_SWITCH_MAX 2
 #define SCARLETT2_INPUT_GAIN_MAX 2
 
@@ -245,6 +252,59 @@ static const u16 scarlett2_mixer_values[SCARLETT2_MIXER_VALUE_COUNT] = {
 /* Maximum number of meters (sum of output port counts) */
 #define SCARLETT2_MAX_METERS 65
 
+/* Compressor parameter data
+ *
+ * The compressor parameters are 32-bit fixed point values with 24
+ * bits of fraction. Integer values are sufficient for the parameters
+ * except for ratio which we can set in 0.5:1 steps.
+ */
+struct compressor_param {
+	const char          *name;
+	snd_ctl_elem_type_t  type;
+	s32                  min;
+	s32                  max;
+	int                  scale_bits;
+};
+
+/* The available compressor parameters on the Vocaster:
+ * - Enable: Off, On
+ * - Threshold: -40dB to 0dB
+ * - Ratio: 1:1 to 50:1 in 0.5:1 steps
+ * - Knee Width: 0dB to 10dB
+ * - Attack: 30ms to 127ms
+ * - Release: 30ms to 127ms
+ * - Makeup Gain: 0dB to 24dB
+ */
+static const struct compressor_param compressor_params[] = {
+	{ "Enable",      SNDRV_CTL_ELEM_TYPE_BOOLEAN,   0,   1,  0 },
+	{ "Threshold",   SNDRV_CTL_ELEM_TYPE_INTEGER, -40,   0, 24 },
+	{ "Ratio",       SNDRV_CTL_ELEM_TYPE_INTEGER,   2, 100, 23 },
+	{ "Knee Width",  SNDRV_CTL_ELEM_TYPE_INTEGER,   0,  10, 24 },
+	{ "Attack",      SNDRV_CTL_ELEM_TYPE_INTEGER,  30, 127, 24 },
+	{ "Release",     SNDRV_CTL_ELEM_TYPE_INTEGER,  30, 127, 24 },
+	{ "Makeup Gain", SNDRV_CTL_ELEM_TYPE_INTEGER,   0,  24, 24 },
+};
+
+#define SCARLETT2_COMPRESSOR_PARAM_COUNT ARRAY_SIZE(compressor_params)
+#define SCARLETT2_COMPRESSOR_CTLS_MAX \
+	(SCARLETT2_COMPRESSOR_PARAM_COUNT * SCARLETT2_DSP_SWITCH_MAX)
+
+/* Maximum number of filter controls */
+#define SCARLETT2_PRECOMP_FLT_CTLS_MAX (2 * SCARLETT2_DSP_SWITCH_MAX)
+#define SCARLETT2_PEQ_FLT_CTLS_MAX (3 * SCARLETT2_DSP_SWITCH_MAX)
+
+/* Number of biquad filter coefficients */
+#define SCARLETT2_BIQUAD_COEFFS 5
+
+/* Maximum number of filter coefficient values */
+#define SCARLETT2_PRECOMP_FLT_VALUES_MAX \
+	(SCARLETT2_PRECOMP_FLT_CTLS_MAX * SCARLETT2_BIQUAD_COEFFS)
+#define SCARLETT2_PEQ_FLT_VALUES_MAX \
+	(SCARLETT2_PEQ_FLT_CTLS_MAX * SCARLETT2_BIQUAD_COEFFS)
+
+/* Maximum number of PEQ filter slots */
+#define SCARLETT2_PEQ_FLT_SLOTS_MAX 4
+
 /* Hardware port types:
  * - None (no input to mux)
  * - Analogue I/O
@@ -277,6 +337,17 @@ enum {
 	SCARLETT2_DIM_MUTE_COUNT
 };
 
+/* Autogain target values */
+
+#define SCARLETT2_AG_TARGET_MIN (-30)
+
+enum {
+	SCARLETT2_AG_HOT_TARGET,
+	SCARLETT2_AG_MEAN_TARGET,
+	SCARLETT2_AG_PEAK_TARGET,
+	SCARLETT2_AG_TARGET_COUNT
+};
+
 /* Flash Write State */
 enum {
 	SCARLETT2_FLASH_WRITE_STATE_IDLE,
@@ -295,7 +366,7 @@ static const char *const scarlett2_dim_mute_names[SCARLETT2_DIM_MUTE_COUNT] = {
  * If autogain_switch is set, autogain_status is set to 0 (Running).
  * The other status values are from the raw_autogain_status value + 1.
  */
-static const char *const scarlett2_autogain_status_texts[] = {
+static const char *const scarlett2_autogain_status_gen4[] = {
 	"Running",
 	"Success",
 	"SuccessDRover",
@@ -304,7 +375,20 @@ static const char *const scarlett2_autogain_status_texts[] = {
 	"FailMaxGainLimit",
 	"FailClipped",
 	"Cancelled",
-	"Invalid"
+	"Invalid",
+	NULL
+};
+
+static const char *const scarlett2_autogain_status_vocaster[] = {
+	"Running",
+	"Success",
+	"FailPG",
+	"FailRange",
+	"WarnMaxCap",
+	"WarnMinCap",
+	"Cancelled",
+	"Invalid",
+	NULL
 };
 
 /* Power Status Values */
@@ -321,6 +405,7 @@ struct scarlett2_notification {
 	void (*func)(struct usb_mixer_interface *mixer);
 };
 
+static void scarlett2_notify_ack(struct usb_mixer_interface *mixer);
 static void scarlett2_notify_sync(struct usb_mixer_interface *mixer);
 static void scarlett2_notify_dim_mute(struct usb_mixer_interface *mixer);
 static void scarlett2_notify_monitor(struct usb_mixer_interface *mixer);
@@ -328,6 +413,8 @@ 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_dsp(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);
@@ -339,11 +426,12 @@ static void scarlett2_notify_direct_monitor(struct usb_mixer_interface *mixer);
 static void scarlett2_notify_power_status(struct usb_mixer_interface *mixer);
 static void scarlett2_notify_pcm_input_switch(
 					struct usb_mixer_interface *mixer);
+static void scarlett2_notify_bluetooth(struct usb_mixer_interface *mixer);
 
 /* Arrays of notification callback functions */
 
 static const struct scarlett2_notification scarlett2_notifications[] = {
-	{ 0x00000001, NULL }, /* ack, gets ignored */
+	{ 0x00000001, scarlett2_notify_ack },
 	{ 0x00000008, scarlett2_notify_sync },
 	{ 0x00200000, scarlett2_notify_dim_mute },
 	{ 0x00400000, scarlett2_notify_monitor },
@@ -353,14 +441,26 @@ static const struct scarlett2_notification scarlett2_notifications[] = {
 };
 
 static const struct scarlett2_notification scarlett3a_notifications[] = {
-	{ 0x00000001, NULL }, /* ack, gets ignored */
+	{ 0x00000001, scarlett2_notify_ack },
 	{ 0x00800000, scarlett2_notify_input_other },
 	{ 0x01000000, scarlett2_notify_direct_monitor },
 	{ 0, NULL }
 };
 
+static const struct scarlett2_notification vocaster_notifications[] = {
+	{ 0x00000001, scarlett2_notify_ack },
+	{ 0x00000008, scarlett2_notify_sync },
+	{ 0x00200000, scarlett2_notify_input_mute },
+	{ 0x00400000, scarlett2_notify_autogain },
+	{ 0x04000000, scarlett2_notify_input_dsp },
+	{ 0x08000000, scarlett2_notify_input_gain },
+	{ 0x10000000, scarlett2_notify_input_phantom },
+	{ 0x20000000, scarlett2_notify_bluetooth },
+	{ 0, NULL }
+};
+
 static const struct scarlett2_notification scarlett4_solo_notifications[] = {
-	{ 0x00000001, NULL }, /* ack, gets ignored */
+	{ 0x00000001, scarlett2_notify_ack },
 	{ 0x00000008, scarlett2_notify_sync },
 	{ 0x00400000, scarlett2_notify_input_air },
 	{ 0x00800000, scarlett2_notify_direct_monitor },
@@ -371,7 +471,7 @@ static const struct scarlett2_notification scarlett4_solo_notifications[] = {
 };
 
 static const struct scarlett2_notification scarlett4_2i2_notifications[] = {
-	{ 0x00000001, NULL }, /* ack, gets ignored */
+	{ 0x00000001, scarlett2_notify_ack },
 	{ 0x00000008, scarlett2_notify_sync },
 	{ 0x00200000, scarlett2_notify_input_safe },
 	{ 0x00400000, scarlett2_notify_autogain },
@@ -387,7 +487,7 @@ static const struct scarlett2_notification scarlett4_2i2_notifications[] = {
 };
 
 static const struct scarlett2_notification scarlett4_4i4_notifications[] = {
-	{ 0x00000001, NULL }, /* ack, gets ignored */
+	{ 0x00000001, scarlett2_notify_ack },
 	{ 0x00000008, scarlett2_notify_sync },
 	{ 0x00200000, scarlett2_notify_input_safe },
 	{ 0x00400000, scarlett2_notify_autogain },
@@ -414,6 +514,13 @@ enum {
 	SCARLETT2_CONFIG_PAD_SWITCH,
 	SCARLETT2_CONFIG_MSD_SWITCH,
 	SCARLETT2_CONFIG_AIR_SWITCH,
+	SCARLETT2_CONFIG_DSP_SWITCH,
+	SCARLETT2_CONFIG_COMPRESSOR_PARAMS,
+	SCARLETT2_CONFIG_PRECOMP_FLT_SWITCH,
+	SCARLETT2_CONFIG_PRECOMP_FLT_PARAMS,
+	SCARLETT2_CONFIG_PEQ_FLT_SWITCH,
+	SCARLETT2_CONFIG_PEQ_FLT_PARAMS,
+	SCARLETT2_CONFIG_INPUT_MUTE_SWITCH,
 	SCARLETT2_CONFIG_STANDALONE_SWITCH,
 	SCARLETT2_CONFIG_PHANTOM_SWITCH,
 	SCARLETT2_CONFIG_PHANTOM_PERSISTENCE,
@@ -423,6 +530,9 @@ enum {
 	SCARLETT2_CONFIG_TALKBACK_MAP,
 	SCARLETT2_CONFIG_AUTOGAIN_SWITCH,
 	SCARLETT2_CONFIG_AUTOGAIN_STATUS,
+	SCARLETT2_CONFIG_AG_HOT_TARGET,
+	SCARLETT2_CONFIG_AG_MEAN_TARGET,
+	SCARLETT2_CONFIG_AG_PEAK_TARGET,
 	SCARLETT2_CONFIG_INPUT_GAIN,
 	SCARLETT2_CONFIG_SAFE_SWITCH,
 	SCARLETT2_CONFIG_INPUT_SELECT_SWITCH,
@@ -431,15 +541,30 @@ enum {
 	SCARLETT2_CONFIG_POWER_LOW,
 	SCARLETT2_CONFIG_PCM_INPUT_SWITCH,
 	SCARLETT2_CONFIG_DIRECT_MONITOR_GAIN,
+	SCARLETT2_CONFIG_BLUETOOTH_VOLUME,
+	SCARLETT2_CONFIG_SPDIF_MODE,
 	SCARLETT2_CONFIG_COUNT
 };
 
+/* Autogain target configuration parameters and names */
+
+static const int scarlett2_ag_target_configs[] = {
+	[SCARLETT2_AG_HOT_TARGET]  = SCARLETT2_CONFIG_AG_HOT_TARGET,
+	[SCARLETT2_AG_MEAN_TARGET] = SCARLETT2_CONFIG_AG_MEAN_TARGET,
+	[SCARLETT2_AG_PEAK_TARGET] = SCARLETT2_CONFIG_AG_PEAK_TARGET
+};
+
+static const char *const scarlett2_ag_target_names[] = {
+	"Hot", "Mean", "Peak"
+};
+
 /* Location, size, and activation command number for the configuration
- * parameters. Size is in bits and may be 0, 1, 8, or 16.
+ * parameters. Size is in bits and may be 1, 8, 16, or 32.
  *
- * A size of 0 indicates that the parameter is a byte-sized Scarlett
- * Gen 4 configuration which is written through the gen4_write_addr
- * location (but still read through the given offset location).
+ * Vocaster and 4th Gen devices have a parameter buffer to set certain
+ * configuration parameters. When pbuf is set, rather than writing to
+ * the given offset, the channel and value are written to the
+ * parameter buffer and the activate command is sent to the device.
  *
  * Some Gen 4 configuration parameters are written with 0x02 for a
  * desired value of 0x01, and 0x03 for 0x00. These are indicated with
@@ -451,15 +576,28 @@ struct scarlett2_config {
 	u16 offset;
 	u8 size;
 	u8 activate;
+	u8 pbuf;
 	u8 mute;
 };
 
 struct scarlett2_config_set {
 	const struct scarlett2_notification *notifications;
-	u16 gen4_write_addr;
+	u16 param_buf_addr;
+	const unsigned int *input_gain_tlv;
+	const char *const *autogain_status_texts;
 	const struct scarlett2_config items[SCARLETT2_CONFIG_COUNT];
 };
 
+/* Input gain TLV dB ranges */
+
+static const DECLARE_TLV_DB_MINMAX(
+	db_scale_vocaster_gain, 0, 70 * 100
+);
+
+static const DECLARE_TLV_DB_MINMAX(
+	db_scale_gen4_gain, 0, 69 * 100
+);
+
 /* Gen 2 devices without SW/HW volume switch: 6i6, 18i8 */
 
 static const struct scarlett2_config_set scarlett2_config_set_gen2a = {
@@ -618,31 +756,87 @@ static const struct scarlett2_config_set scarlett2_config_set_gen3c = {
 
 		[SCARLETT2_CONFIG_TALKBACK_MAP] = {
 			.offset = 0xb0, .size = 16, .activate = 10 },
+
+		[SCARLETT2_CONFIG_SPDIF_MODE] = {
+			.offset = 0x94, .size = 8, .activate = 6 },
+	}
+};
+
+/* Vocaster */
+static const struct scarlett2_config_set scarlett2_config_set_vocaster = {
+	.notifications = vocaster_notifications,
+	.param_buf_addr = 0x1bc,
+	.input_gain_tlv = db_scale_vocaster_gain,
+	.autogain_status_texts = scarlett2_autogain_status_vocaster,
+	.items = {
+		[SCARLETT2_CONFIG_MSD_SWITCH] = {
+			.offset = 0x9d, .size = 8, .activate = 6 },
+
+		[SCARLETT2_CONFIG_AUTOGAIN_SWITCH] = {
+			.offset = 0x1c0, .size = 8, .activate = 19, .pbuf = 1 },
+
+		[SCARLETT2_CONFIG_AUTOGAIN_STATUS] = {
+			.offset = 0x1c2, .size = 8, },
+
+		[SCARLETT2_CONFIG_AG_HOT_TARGET] = {
+			.offset = 0xc1, .size = 8, .activate = 29, .pbuf = 1 },
+
+		[SCARLETT2_CONFIG_INPUT_GAIN] = {
+			.offset = 0x9f, .size = 8, .activate = 21, .pbuf = 1 },
+
+		[SCARLETT2_CONFIG_PHANTOM_SWITCH] = {
+			.offset = 0x9c, .size = 1, .activate = 20, .pbuf = 1 },
+
+		[SCARLETT2_CONFIG_DSP_SWITCH] = {
+			.offset = 0x1c4, .size = 8, .activate = 22, .pbuf = 1 },
+
+		[SCARLETT2_CONFIG_COMPRESSOR_PARAMS] = {
+			.offset = 0x1c8, .size = 32, .activate = 23 },
+
+		[SCARLETT2_CONFIG_PRECOMP_FLT_SWITCH] = {
+			.offset = 0x7c, .size = 32, .activate = 27 },
+
+		[SCARLETT2_CONFIG_PRECOMP_FLT_PARAMS] = {
+			.offset = 0x200, .size = 32, .activate = 27 },
+
+		[SCARLETT2_CONFIG_PEQ_FLT_SWITCH] = {
+			.offset = 0x84, .size = 32, .activate = 27 },
+
+		[SCARLETT2_CONFIG_PEQ_FLT_PARAMS] = {
+			.offset = 0x250, .size = 32, .activate = 27 },
+
+		[SCARLETT2_CONFIG_INPUT_MUTE_SWITCH] = {
+			.offset = 0x1be, .size = 8, .activate = 17, .pbuf = 1 },
+
+		[SCARLETT2_CONFIG_BLUETOOTH_VOLUME] = {
+			.offset = 0xbf, .size = 8, .activate = 28 },
 	}
 };
 
 /* Solo Gen 4 */
 static const struct scarlett2_config_set scarlett2_config_set_gen4_solo = {
 	.notifications = scarlett4_solo_notifications,
-	.gen4_write_addr = 0xd8,
+	.param_buf_addr = 0xd8,
 	.items = {
 		[SCARLETT2_CONFIG_MSD_SWITCH] = {
 			.offset = 0x47, .size = 8, .activate = 4 },
 
 		[SCARLETT2_CONFIG_DIRECT_MONITOR] = {
-			.offset = 0x108, .activate = 12 },
+			.offset = 0x108, .size = 8, .activate = 12, .pbuf = 1 },
 
 		[SCARLETT2_CONFIG_PHANTOM_SWITCH] = {
-			.offset = 0x46, .activate = 9, .mute = 1 },
+			.offset = 0x46, .size = 8, .activate = 9, .pbuf = 1,
+			.mute = 1 },
 
 		[SCARLETT2_CONFIG_LEVEL_SWITCH] = {
-			.offset = 0x3d, .activate = 10, .mute = 1 },
+			.offset = 0x3d, .size = 8, .activate = 10, .pbuf = 1,
+			.mute = 1 },
 
 		[SCARLETT2_CONFIG_AIR_SWITCH] = {
-			.offset = 0x3e, .activate = 11 },
+			.offset = 0x3e, .size = 8, .activate = 11, .pbuf = 1 },
 
 		[SCARLETT2_CONFIG_PCM_INPUT_SWITCH] = {
-			.offset = 0x206, .activate = 25 },
+			.offset = 0x206, .size = 8, .activate = 25, .pbuf = 1 },
 
 		[SCARLETT2_CONFIG_DIRECT_MONITOR_GAIN] = {
 			.offset = 0x232, .size = 16, .activate = 26 }
@@ -652,40 +846,50 @@ static const struct scarlett2_config_set scarlett2_config_set_gen4_solo = {
 /* 2i2 Gen 4 */
 static const struct scarlett2_config_set scarlett2_config_set_gen4_2i2 = {
 	.notifications = scarlett4_2i2_notifications,
-	.gen4_write_addr = 0xfc,
+	.param_buf_addr = 0xfc,
+	.input_gain_tlv = db_scale_gen4_gain,
+	.autogain_status_texts = scarlett2_autogain_status_gen4,
 	.items = {
 		[SCARLETT2_CONFIG_MSD_SWITCH] = {
-			.offset = 0x49, .size = 8, .activate = 4 }, // 0x41 ??
+			.offset = 0x49, .size = 8, .activate = 4 },
 
 		[SCARLETT2_CONFIG_DIRECT_MONITOR] = {
-			.offset = 0x14a, .activate = 16 },
+			.offset = 0x14a, .size = 8, .activate = 16, .pbuf = 1 },
 
 		[SCARLETT2_CONFIG_AUTOGAIN_SWITCH] = {
-			.offset = 0x135, .activate = 10 },
+			.offset = 0x135, .size = 8, .activate = 10, .pbuf = 1 },
 
 		[SCARLETT2_CONFIG_AUTOGAIN_STATUS] = {
-			.offset = 0x137 },
+			.offset = 0x137, .size = 8 },
+
+		[SCARLETT2_CONFIG_AG_MEAN_TARGET] = {
+			.offset = 0x131, .size = 8, .activate = 29, .pbuf = 1 },
+
+		[SCARLETT2_CONFIG_AG_PEAK_TARGET] = {
+			.offset = 0x132, .size = 8, .activate = 30, .pbuf = 1 },
 
 		[SCARLETT2_CONFIG_PHANTOM_SWITCH] = {
-			.offset = 0x48, .activate = 11, .mute = 1 },
+			.offset = 0x48, .size = 8, .activate = 11, .pbuf = 1,
+			.mute = 1 },
 
 		[SCARLETT2_CONFIG_INPUT_GAIN] = {
-			.offset = 0x4b, .activate = 12 },
+			.offset = 0x4b, .size = 8, .activate = 12, .pbuf = 1 },
 
 		[SCARLETT2_CONFIG_LEVEL_SWITCH] = {
-			.offset = 0x3c, .activate = 13, .mute = 1 },
+			.offset = 0x3c, .size = 8, .activate = 13, .pbuf = 1,
+			.mute = 1 },
 
 		[SCARLETT2_CONFIG_SAFE_SWITCH] = {
-			.offset = 0x147, .activate = 14 },
+			.offset = 0x147, .size = 8, .activate = 14, .pbuf = 1 },
 
 		[SCARLETT2_CONFIG_AIR_SWITCH] = {
-			.offset = 0x3e, .activate = 15 },
+			.offset = 0x3e, .size = 8, .activate = 15, .pbuf = 1 },
 
 		[SCARLETT2_CONFIG_INPUT_SELECT_SWITCH] = {
-			.offset = 0x14b, .activate = 17 },
+			.offset = 0x14b, .size = 8, .activate = 17, .pbuf = 1 },
 
 		[SCARLETT2_CONFIG_INPUT_LINK_SWITCH] = {
-			.offset = 0x14e, .activate = 18 },
+			.offset = 0x14e, .size = 8, .activate = 18, .pbuf = 1 },
 
 		[SCARLETT2_CONFIG_DIRECT_MONITOR_GAIN] = {
 			.offset = 0x2a0, .size = 16, .activate = 36 }
@@ -695,37 +899,47 @@ static const struct scarlett2_config_set scarlett2_config_set_gen4_2i2 = {
 /* 4i4 Gen 4 */
 static const struct scarlett2_config_set scarlett2_config_set_gen4_4i4 = {
 	.notifications = scarlett4_4i4_notifications,
-	.gen4_write_addr = 0x130,
+	.param_buf_addr = 0x130,
+	.input_gain_tlv = db_scale_gen4_gain,
+	.autogain_status_texts = scarlett2_autogain_status_gen4,
 	.items = {
 		[SCARLETT2_CONFIG_MSD_SWITCH] = {
 			.offset = 0x5c, .size = 8, .activate = 4 },
 
 		[SCARLETT2_CONFIG_AUTOGAIN_SWITCH] = {
-			.offset = 0x13e, .activate = 10 },
+			.offset = 0x13e, .size = 8, .activate = 10, .pbuf = 1 },
 
 		[SCARLETT2_CONFIG_AUTOGAIN_STATUS] = {
-			.offset = 0x140 },
+			.offset = 0x140, .size = 8 },
+
+		[SCARLETT2_CONFIG_AG_MEAN_TARGET] = {
+			.offset = 0x13a, .size = 8, .activate = 23, .pbuf = 1 },
+
+		[SCARLETT2_CONFIG_AG_PEAK_TARGET] = {
+			.offset = 0x13b, .size = 8, .activate = 24, .pbuf = 1 },
 
 		[SCARLETT2_CONFIG_PHANTOM_SWITCH] = {
-			.offset = 0x5a, .activate = 11, .mute = 1 },
+			.offset = 0x5a, .size = 8, .activate = 11, .pbuf = 1,
+			.mute = 1 },
 
 		[SCARLETT2_CONFIG_INPUT_GAIN] = {
-			.offset = 0x5e, .activate = 12 },
+			.offset = 0x5e, .size = 8, .activate = 12, .pbuf = 1 },
 
 		[SCARLETT2_CONFIG_LEVEL_SWITCH] = {
-			.offset = 0x4e, .activate = 13, .mute = 1 },
+			.offset = 0x4e, .size = 8, .activate = 13, .pbuf = 1,
+			.mute = 1 },
 
 		[SCARLETT2_CONFIG_SAFE_SWITCH] = {
-			.offset = 0x150, .activate = 14 },
+			.offset = 0x150, .size = 8, .activate = 14, .pbuf = 1 },
 
 		[SCARLETT2_CONFIG_AIR_SWITCH] = {
-			.offset = 0x50, .activate = 15 },
+			.offset = 0x50, .size = 8, .activate = 15, .pbuf = 1 },
 
 		[SCARLETT2_CONFIG_INPUT_SELECT_SWITCH] = {
-			.offset = 0x153, .activate = 16 },
+			.offset = 0x153, .size = 8, .activate = 16, .pbuf = 1 },
 
 		[SCARLETT2_CONFIG_INPUT_LINK_SWITCH] = {
-			.offset = 0x156, .activate = 17 },
+			.offset = 0x156, .size = 8, .activate = 17, .pbuf = 1 },
 
 		[SCARLETT2_CONFIG_MASTER_VOLUME] = {
 			.offset = 0x32, .size = 16 },
@@ -734,10 +948,10 @@ static const struct scarlett2_config_set scarlett2_config_set_gen4_4i4 = {
 			.offset = 0x3a, .size = 16 },
 
 		[SCARLETT2_CONFIG_POWER_EXT] = {
-			.offset = 0x168 },
+			.offset = 0x168, .size = 8 },
 
 		[SCARLETT2_CONFIG_POWER_LOW] = {
-			.offset = 0x16d }
+			.offset = 0x16d, .size = 8 }
 	}
 };
 
@@ -768,6 +982,9 @@ static const struct scarlett2_config_set scarlett2_config_set_clarett = {
 
 		[SCARLETT2_CONFIG_STANDALONE_SWITCH] = {
 			.offset = 0x8d, .size = 8, .activate = 6 },
+
+		[SCARLETT2_CONFIG_SPDIF_MODE] = {
+			.offset = 0x9e, .size = 8, .activate = 4 },
 	}
 };
 
@@ -895,6 +1112,23 @@ struct scarlett2_device_info {
 	 */
 	u8 air_option;
 
+	/* the number of analogue inputs with DSP control */
+	u8 dsp_input_count;
+
+	/* number of pre-compressor filters */
+	u8 precomp_flt_count;
+
+	/* number of parametric EQ filters */
+	u8 peq_flt_count;
+
+	/* number of PEQ filters plus unused slots */
+	u8 peq_flt_total_count;
+
+	/* 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;
 
@@ -907,6 +1141,9 @@ struct scarlett2_device_info {
 	/* the number of inputs with software-controllable gain */
 	u8 gain_input_count;
 
+	/* the number of inputs with safe mode */
+	u8 safe_input_count;
+
 	/* the number of direct monitor options
 	 * (0 = none, 1 = mono only, 2 = mono/stereo)
 	 */
@@ -915,6 +1152,14 @@ struct scarlett2_device_info {
 	/* the number of DSP channels */
 	u8 dsp_count;
 
+	/* has a Bluetooth module with volume control */
+	u8 has_bluetooth;
+
+	/* S/PDIF Source/Digital I/O mode control */
+	const char * const spdif_mode_control_name;
+	const u8 *spdif_mode_values;
+	const char * const *spdif_mode_texts;
+
 	/* remap analogue outputs; 18i8 Gen 3 has "line 3/4" connected
 	 * internally to the analogue 7/8 outputs
 	 */
@@ -942,7 +1187,9 @@ struct scarlett2_device_info {
 struct scarlett2_data {
 	struct usb_mixer_interface *mixer;
 	struct mutex usb_mutex; /* prevent sending concurrent USB requests */
+	struct completion cmd_done;
 	struct mutex data_mutex; /* lock access to this data */
+	u8 running;
 	u8 hwdep_in_use;
 	u8 selected_flash_segment_id;
 	u8 flash_write_state;
@@ -960,6 +1207,7 @@ struct scarlett2_data {
 	u8 num_mix_out;
 	u8 num_line_out;
 	u8 num_monitor_mix_ctls;
+	u8 num_autogain_status_texts;
 	u32 firmware_version;
 	u8 flash_segment_nums[SCARLETT2_SEGMENT_ID_COUNT];
 	u8 flash_segment_blocks[SCARLETT2_SEGMENT_ID_COUNT];
@@ -970,6 +1218,8 @@ struct scarlett2_data {
 	u8 input_level_updated;
 	u8 input_pad_updated;
 	u8 input_air_updated;
+	u8 input_dsp_updated;
+	u8 input_mute_updated;
 	u8 input_phantom_updated;
 	u8 input_select_updated;
 	u8 input_gain_updated;
@@ -982,6 +1232,7 @@ struct scarlett2_data {
 	u8 mix_updated;
 	u8 speaker_switching_switched;
 	u8 power_status_updated;
+	u8 bluetooth_updated;
 	u8 sync;
 	u8 master_vol;
 	u8 headphone_vol;
@@ -992,6 +1243,13 @@ 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 dsp_switch[SCARLETT2_DSP_SWITCH_MAX];
+	s32 compressor_values[SCARLETT2_COMPRESSOR_CTLS_MAX];
+	s32 precomp_flt_values[SCARLETT2_PRECOMP_FLT_VALUES_MAX];
+	s32 peq_flt_values[SCARLETT2_PEQ_FLT_VALUES_MAX];
+	u8 precomp_flt_switch[SCARLETT2_DSP_SWITCH_MAX];
+	u8 peq_flt_switch[SCARLETT2_DSP_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;
@@ -999,6 +1257,7 @@ struct scarlett2_data {
 	u8 gain[SCARLETT2_INPUT_GAIN_MAX];
 	u8 autogain_switch[SCARLETT2_INPUT_GAIN_MAX];
 	u8 autogain_status[SCARLETT2_INPUT_GAIN_MAX];
+	s8 ag_targets[SCARLETT2_AG_TARGET_COUNT];
 	u8 safe_switch[SCARLETT2_INPUT_GAIN_MAX];
 	u8 pcm_input_switch;
 	u8 direct_monitor_switch;
@@ -1008,6 +1267,8 @@ struct scarlett2_data {
 	u8 msd_switch;
 	u8 standalone_switch;
 	u8 power_status;
+	u8 bluetooth_volume;
+	u8 spdif_mode;
 	u8 meter_level_map[SCARLETT2_MAX_METERS];
 	struct snd_kcontrol *sync_ctl;
 	struct snd_kcontrol *master_vol_ctl;
@@ -1019,20 +1280,29 @@ 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 *dsp_ctls[SCARLETT2_DSP_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];
 	struct snd_kcontrol *input_gain_ctls[SCARLETT2_INPUT_GAIN_MAX];
 	struct snd_kcontrol *autogain_ctls[SCARLETT2_INPUT_GAIN_MAX];
 	struct snd_kcontrol *autogain_status_ctls[SCARLETT2_INPUT_GAIN_MAX];
+	struct snd_kcontrol *ag_target_ctls[SCARLETT2_AG_TARGET_COUNT];
 	struct snd_kcontrol *safe_ctls[SCARLETT2_INPUT_GAIN_MAX];
 	struct snd_kcontrol *pcm_input_switch_ctl;
 	struct snd_kcontrol *mux_ctls[SCARLETT2_MUX_MAX];
 	struct snd_kcontrol *mix_ctls[SCARLETT2_MIX_MAX];
+	struct snd_kcontrol *compressor_ctls[SCARLETT2_COMPRESSOR_CTLS_MAX];
+	struct snd_kcontrol *precomp_flt_ctls[SCARLETT2_PRECOMP_FLT_CTLS_MAX];
+	struct snd_kcontrol *peq_flt_ctls[SCARLETT2_PEQ_FLT_CTLS_MAX];
+	struct snd_kcontrol *precomp_flt_switch_ctls[SCARLETT2_DSP_SWITCH_MAX];
+	struct snd_kcontrol *peq_flt_switch_ctls[SCARLETT2_DSP_SWITCH_MAX];
 	struct snd_kcontrol *direct_monitor_ctl;
 	struct snd_kcontrol *speaker_switching_ctl;
 	struct snd_kcontrol *talkback_ctl;
 	struct snd_kcontrol *power_status_ctl;
+	struct snd_kcontrol *bluetooth_volume_ctl;
 	u8 mux[SCARLETT2_MUX_MAX];
 	u8 mix[SCARLETT2_MIX_MAX];
 	u8 monitor_mix[SCARLETT2_MONITOR_MIX_MAX];
@@ -1326,6 +1596,14 @@ static const struct scarlett2_device_info s8i6_gen3_info = {
 	}
 };
 
+static const u8 scarlett2_spdif_s18i8_gen3_values[] = { 0, 2, 0xff };
+
+static const char * const scarlett2_spdif_s18i8_gen3_texts[] = {
+	"RCA",
+	"Optical",
+	NULL
+};
+
 static const struct scarlett2_device_info s18i8_gen3_info = {
 	.config_set = &scarlett2_config_set_gen3c,
 	.has_speaker_switching = 1,
@@ -1335,6 +1613,10 @@ static const struct scarlett2_device_info s18i8_gen3_info = {
 	.phantom_count = 2,
 	.inputs_per_phantom = 2,
 
+	.spdif_mode_control_name = "S/PDIF Mode Capture Enum",
+	.spdif_mode_values = scarlett2_spdif_s18i8_gen3_values,
+	.spdif_mode_texts = scarlett2_spdif_s18i8_gen3_texts,
+
 	.line_out_remap_enable = 1,
 	.line_out_remap = { 0, 1, 6, 7, 2, 3, 4, 5 },
 	.line_out_unmap = { 0, 1, 4, 5, 6, 7, 2, 3 },
@@ -1405,6 +1687,15 @@ static const struct scarlett2_device_info s18i8_gen3_info = {
 	}
 };
 
+static const u8 scarlett2_spdif_s18i20_gen3_values[] = { 0, 6, 1, 0xff };
+
+static const char * const scarlett2_spdif_s18i20_gen3_texts[] = {
+	"S/PDIF RCA",
+	"S/PDIF Optical",
+	"Dual ADAT",
+	NULL
+};
+
 static const struct scarlett2_device_info s18i20_gen3_info = {
 	.config_set = &scarlett2_config_set_gen3c,
 	.has_speaker_switching = 1,
@@ -1415,6 +1706,10 @@ static const struct scarlett2_device_info s18i20_gen3_info = {
 	.phantom_count = 2,
 	.inputs_per_phantom = 4,
 
+	.spdif_mode_control_name = "Digital I/O Mode Capture Enum",
+	.spdif_mode_values = scarlett2_spdif_s18i20_gen3_values,
+	.spdif_mode_texts = scarlett2_spdif_s18i20_gen3_texts,
+
 	.line_out_descrs = {
 		"Monitor 1 L",
 		"Monitor 1 R",
@@ -1475,6 +1770,91 @@ static const struct scarlett2_device_info s18i20_gen3_info = {
 	}
 };
 
+static const struct scarlett2_device_info vocaster_one_info = {
+	.config_set = &scarlett2_config_set_vocaster,
+	.min_firmware_version = 1769,
+
+	.phantom_count = 1,
+	.inputs_per_phantom = 1,
+	.dsp_count = 1,
+	.dsp_input_count = 1,
+	.precomp_flt_count = 2,
+	.peq_flt_count = 3,
+	.peq_flt_total_count = 4,
+	.mute_input_count = 1,
+	.gain_input_count = 1,
+
+	.port_count = {
+		[SCARLETT2_PORT_TYPE_NONE]     = { 1,  0 },
+		[SCARLETT2_PORT_TYPE_ANALOGUE] = { 2,  4 },
+		[SCARLETT2_PORT_TYPE_MIX]      = { 9,  9 },
+		[SCARLETT2_PORT_TYPE_PCM]      = { 4, 10 },
+	},
+
+	.mux_assignment = { {
+		{ SCARLETT2_PORT_TYPE_MIX,      8, 1 },
+		{ SCARLETT2_PORT_TYPE_PCM,      5, 5 },
+		{ SCARLETT2_PORT_TYPE_MIX,      6, 2 },
+		{ SCARLETT2_PORT_TYPE_PCM,      0, 5 },
+		{ SCARLETT2_PORT_TYPE_MIX,      0, 6 },
+		{ SCARLETT2_PORT_TYPE_ANALOGUE, 0, 4 },
+		{ 0, 0, 0 },
+	} },
+
+	.meter_map = {
+		{ 12, 1 },
+		{ 18, 5 },
+		{ 10, 2 },
+		{ 13, 5 },
+		{  4, 6 },
+		{  0, 4 },
+		{  0, 0 }
+	}
+};
+
+static const struct scarlett2_device_info vocaster_two_info = {
+	.config_set = &scarlett2_config_set_vocaster,
+	.min_firmware_version = 1769,
+
+	.phantom_count = 2,
+	.inputs_per_phantom = 1,
+	.dsp_count = 2,
+	.dsp_input_count = 2,
+	.precomp_flt_count = 2,
+	.peq_flt_count = 3,
+	.peq_flt_total_count = 4,
+	.mute_input_count = 2,
+	.gain_input_count = 2,
+	.has_bluetooth = 1,
+
+	.port_count = {
+		[SCARLETT2_PORT_TYPE_NONE]     = {  1,  0 },
+		[SCARLETT2_PORT_TYPE_ANALOGUE] = {  6,  6 },
+		[SCARLETT2_PORT_TYPE_MIX]      = { 12, 14 },
+		[SCARLETT2_PORT_TYPE_PCM]      = {  4, 14 },
+	},
+
+	.mux_assignment = { {
+		{ SCARLETT2_PORT_TYPE_MIX,      12,  2 },
+		{ SCARLETT2_PORT_TYPE_PCM,       6,  8 },
+		{ SCARLETT2_PORT_TYPE_MIX,      10,  2 },
+		{ SCARLETT2_PORT_TYPE_PCM,       0,  6 },
+		{ SCARLETT2_PORT_TYPE_MIX,       0, 10 },
+		{ SCARLETT2_PORT_TYPE_ANALOGUE,  0,  6 },
+		{ 0, 0, 0 },
+	} },
+
+	.meter_map = {
+		{ 18,  2 },
+		{ 26,  8 },
+		{ 16,  2 },
+		{ 20,  6 },
+		{  6, 10 },
+		{  0,  6 },
+		{  0,  0 }
+	}
+};
+
 static const struct scarlett2_device_info solo_gen4_info = {
 	.config_set = &scarlett2_config_set_gen4_solo,
 	.min_firmware_version = 2115,
@@ -1539,6 +1919,7 @@ static const struct scarlett2_device_info s2i2_gen4_info = {
 	.phantom_count = 1,
 	.inputs_per_phantom = 2,
 	.gain_input_count = 2,
+	.safe_input_count = 2,
 	.direct_monitor = 2,
 	.dsp_count = 2,
 
@@ -1592,6 +1973,7 @@ static const struct scarlett2_device_info s4i4_gen4_info = {
 	.phantom_count = 2,
 	.inputs_per_phantom = 1,
 	.gain_input_count = 2,
+	.safe_input_count = 2,
 	.dsp_count = 2,
 
 	.port_count = {
@@ -1676,11 +2058,24 @@ static const struct scarlett2_device_info clarett_2pre_info = {
 	}
 };
 
+static const u8 scarlett2_spdif_clarett_values[] = { 0, 1, 2, 0xff };
+
+static const char * const scarlett2_spdif_clarett_texts[] = {
+	"None",
+	"Optical",
+	"RCA",
+	NULL
+};
+
 static const struct scarlett2_device_info clarett_4pre_info = {
 	.config_set = &scarlett2_config_set_clarett,
 	.level_input_count = 2,
 	.air_input_count = 4,
 
+	.spdif_mode_control_name = "S/PDIF Source Capture Enum",
+	.spdif_mode_values = scarlett2_spdif_clarett_values,
+	.spdif_mode_texts = scarlett2_spdif_clarett_texts,
+
 	.line_out_descrs = {
 		"Monitor L",
 		"Monitor R",
@@ -1733,6 +2128,10 @@ static const struct scarlett2_device_info clarett_8pre_info = {
 	.level_input_count = 2,
 	.air_input_count = 8,
 
+	.spdif_mode_control_name = "S/PDIF Source Capture Enum",
+	.spdif_mode_values = scarlett2_spdif_clarett_values,
+	.spdif_mode_texts = scarlett2_spdif_clarett_texts,
+
 	.line_out_descrs = {
 		"Monitor L",
 		"Monitor R",
@@ -1806,6 +2205,10 @@ static const struct scarlett2_device_entry scarlett2_devices[] = {
 	{ USB_ID(0x1235, 0x8214), &s18i8_gen3_info, "Scarlett Gen 3" },
 	{ USB_ID(0x1235, 0x8215), &s18i20_gen3_info, "Scarlett Gen 3" },
 
+	/* Supported Vocaster devices */
+	{ USB_ID(0x1235, 0x8216), &vocaster_one_info, "Vocaster" },
+	{ USB_ID(0x1235, 0x8217), &vocaster_two_info, "Vocaster" },
+
 	/* Supported Gen 4 devices */
 	{ USB_ID(0x1235, 0x8218), &solo_gen4_info, "Scarlett Gen 4" },
 	{ USB_ID(0x1235, 0x8219), &s2i2_gen4_info, "Scarlett Gen 4" },
@@ -1856,6 +2259,7 @@ static int scarlett2_get_port_start_num(
 #define SCARLETT2_USB_ERASE_SEGMENT 0x00004002
 #define SCARLETT2_USB_GET_ERASE     0x00004003
 #define SCARLETT2_USB_WRITE_SEGMENT 0x00004004
+#define SCARLETT2_USB_READ_SEGMENT  0x00004005
 #define SCARLETT2_USB_GET_SYNC      0x00006004
 #define SCARLETT2_USB_GET_DATA      0x00800000
 #define SCARLETT2_USB_SET_DATA      0x00800001
@@ -1866,7 +2270,7 @@ static int scarlett2_get_port_start_num(
 #define SCARLETT2_USB_METER_LEVELS_GET_MAGIC 1
 
 #define SCARLETT2_FLASH_BLOCK_SIZE 4096
-#define SCARLETT2_FLASH_WRITE_MAX 1024
+#define SCARLETT2_FLASH_RW_MAX 1024
 #define SCARLETT2_SEGMENT_NUM_MIN 1
 #define SCARLETT2_SEGMENT_NUM_MAX 4
 
@@ -1960,6 +2364,17 @@ static int scarlett2_usb(
 		goto unlock;
 	}
 
+	if (!wait_for_completion_timeout(&private->cmd_done,
+					 msecs_to_jiffies(1000))) {
+		usb_audio_err(
+			mixer->chip,
+			"%s USB request timed out, cmd %x\n",
+			private->series_name, cmd);
+
+		err = -ETIMEDOUT;
+		goto unlock;
+	}
+
 	/* send a second message to get the response */
 
 	err = scarlett2_usb_rx(dev, private->bInterfaceNumber,
@@ -2065,7 +2480,7 @@ static int scarlett2_usb_get_config(
 	if (!config_item->offset)
 		return -EFAULT;
 
-	/* Gen 4 style parameters are always 1 byte */
+	/* Writes to the parameter buffer are always 1 byte */
 	size = config_item->size ? config_item->size : 8;
 
 	/* For byte-sized parameters, retrieve directly into buf */
@@ -2079,6 +2494,11 @@ static int scarlett2_usb_get_config(
 
 			for (i = 0; i < count; i++, buf_16++)
 				*buf_16 = le16_to_cpu(*(__le16 *)buf_16);
+		} else if (size == 4) {
+			u32 *buf_32 = buf;
+
+			for (i = 0; i < count; i++, buf_32++)
+				*buf_32 = le32_to_cpu(*(__le32 *)buf_32);
 		}
 		return 0;
 	}
@@ -2118,6 +2538,54 @@ static int scarlett2_usb_set_data(
 			     &req, sizeof(u32) * 2 + size, NULL, 0);
 }
 
+/* Send a SCARLETT2_USB_SET_DATA command with multiple values.
+ * offset: location in the device's data space
+ * size: size in bytes of each value (1, 2, 4)
+ * count: number of values
+ */
+static int scarlett2_usb_set_data_buf(
+	struct usb_mixer_interface *mixer,
+	int offset, int size, int count, void *buf)
+{
+	struct scarlett2_data *private = mixer->private_data;
+	int bytes = size * count;
+	struct {
+		__le32 offset;
+		__le32 size;
+		u8 data[];
+	} __packed *req;
+	int err;
+	int buf_size = struct_size(req, data, bytes);
+
+	req = kmalloc(buf_size, GFP_KERNEL);
+	if (!req)
+		return -ENOMEM;
+
+	req->offset = cpu_to_le32(offset);
+	req->size = cpu_to_le32(bytes);
+	if (size == 1) {
+		memcpy(req->data, buf, count);
+	} else if (size == 2) {
+		u16 *buf_16 = buf;
+		int i;
+
+		for (i = 0; i < count; i++)
+			((__le16 *)req->data)[i] = cpu_to_le16(buf_16[i]);
+	} else {
+		u32 *buf_32 = buf;
+		int i;
+
+		for (i = 0; i < count; i++)
+			((__le32 *)req->data)[i] = cpu_to_le32(buf_32[i]);
+	}
+
+	err = scarlett2_usb(private->mixer, SCARLETT2_USB_SET_DATA,
+			    req, buf_size, NULL, 0);
+
+	kfree(req);
+	return err;
+}
+
 /* Send a SCARLETT2_USB_DATA_CMD command.
  * Configuration changes require activation with this after they have
  * been uploaded by a previous SCARLETT2_USB_SET_DATA.
@@ -2152,34 +2620,30 @@ static int scarlett2_usb_set_config(
 	if (!config_item->offset)
 		return -EFAULT;
 
-	/* Gen 4 style writes are selected with size = 0;
-	 * these are only byte-sized values written through a shared
-	 * location, different to the read address
-	 */
-	if (!config_item->size) {
-		if (!config_set->gen4_write_addr)
+	/* Write via the parameter buffer? */
+	if (config_item->pbuf) {
+		if (!config_set->param_buf_addr)
 			return -EFAULT;
 
-		/* Place index in gen4_write_addr + 1 */
+		/* Place index in param_buf_addr + 1 */
 		err = scarlett2_usb_set_data(
-			mixer, config_set->gen4_write_addr + 1, 1, index);
+			mixer, config_set->param_buf_addr + 1, 1, index);
 		if (err < 0)
 			return err;
 
-		/* Place value in gen4_write_addr */
+		/* Place value in param_buf_addr */
 		err = scarlett2_usb_set_data(
-			mixer, config_set->gen4_write_addr, 1, value);
+			mixer, config_set->param_buf_addr, 1, value);
 		if (err < 0)
 			return err;
 
-		/* Request the interface do the write */
+		/* Activate the write through the parameter buffer */
 		return scarlett2_usb_activate_config(
 			mixer, config_item->activate);
 	}
 
-	/* Not-Gen 4 style needs NVRAM save, supports
-	 * bit-modification, and writing is done to the same place
-	 * that the value can be read from
+	/* Direct writes (not via the parameter buffer) need NVRAM
+	 * save and support bit-modification
 	 */
 
 	/* Cancel any pending NVRAM save */
@@ -2213,7 +2677,7 @@ static int scarlett2_usb_set_config(
 		value = tmp;
 	}
 
-	/* Send the configuration parameter data */
+	/* Write the new value */
 	err = scarlett2_usb_set_data(mixer, offset, size, value);
 	if (err < 0)
 		return err;
@@ -2223,8 +2687,10 @@ static int scarlett2_usb_set_config(
 	if (err < 0)
 		return err;
 
-	/* Gen 2 style writes to Gen 4 devices don't need saving */
-	if (config_set->gen4_write_addr)
+	/* Interfaces with parameter buffer writes don't need a
+	 * separate save step
+	 */
+	if (config_set->param_buf_addr)
 		return 0;
 
 	/* Schedule the change to be written to NVRAM */
@@ -2234,6 +2700,47 @@ static int scarlett2_usb_set_config(
 	return 0;
 }
 
+/* Send USB messages to set a SCARLETT2_CONFIG_* parameter with
+ * multiple values
+ */
+static int scarlett2_usb_set_config_buf(
+	struct usb_mixer_interface *mixer,
+	int config_item_num, int index, int count, void *buf)
+{
+	struct scarlett2_data *private = mixer->private_data;
+	const struct scarlett2_config_set *config_set = private->config_set;
+	const struct scarlett2_config *config_item =
+		&config_set->items[config_item_num];
+	int offset, size;
+	int err;
+
+	/* Check that the configuration item is present in the
+	 * configuration set used by this device
+	 */
+	if (!config_item->offset)
+		return -EFAULT;
+
+	/* Convert config_item->size in bits to size in bytes and
+	 * calculate offset
+	 */
+	if (config_item->size >= 8) {
+		size = config_item->size / 8;
+		offset = config_item->offset + index * size;
+
+	/* Bit updates not supported */
+	} else {
+		return -EFAULT;
+	}
+
+	/* Write the new values */
+	err = scarlett2_usb_set_data_buf(mixer, offset, size, count, buf);
+	if (err < 0)
+		return err;
+
+	/* Activate the change */
+	return scarlett2_usb_activate_config(mixer, config_item->activate);
+}
+
 /* Send SCARLETT2_USB_DATA_CMD SCARLETT2_USB_CONFIG_SAVE */
 static void scarlett2_config_save(struct usb_mixer_interface *mixer)
 {
@@ -2862,6 +3369,7 @@ static int scarlett2_update_autogain(struct usb_mixer_interface *mixer)
 	const struct scarlett2_device_info *info = private->info;
 	int err, i;
 	u8 raw_autogain_status[SCARLETT2_INPUT_GAIN_MAX];
+	s8 ag_target_values[SCARLETT2_AG_TARGET_COUNT];
 
 	private->autogain_updated = 0;
 
@@ -2893,12 +3401,27 @@ static int scarlett2_update_autogain(struct usb_mixer_interface *mixer)
 		if (private->autogain_switch[i])
 			private->autogain_status[i] = 0;
 		else if (raw_autogain_status[i] <
-				ARRAY_SIZE(scarlett2_autogain_status_texts) - 1)
+				private->num_autogain_status_texts - 1)
 			private->autogain_status[i] =
 				raw_autogain_status[i] + 1;
 		else
 			private->autogain_status[i] =
-				ARRAY_SIZE(scarlett2_autogain_status_texts) - 1;
+				private->num_autogain_status_texts - 1;
+
+
+	for (int i = 0; i < SCARLETT2_AG_TARGET_COUNT; i++)
+		if (scarlett2_has_config_item(private,
+					      scarlett2_ag_target_configs[i])) {
+			err = scarlett2_usb_get_config(
+				mixer, scarlett2_ag_target_configs[i],
+				1, &ag_target_values[i]);
+			if (err < 0)
+				return err;
+		}
+
+	/* convert from negative dBFS as used by the device */
+	for (int i = 0; i < SCARLETT2_AG_TARGET_COUNT; i++)
+		private->ag_targets[i] = -ag_target_values[i];
 
 	return 0;
 }
@@ -2911,19 +3434,34 @@ static void scarlett2_autogain_update_access(struct usb_mixer_interface *mixer)
 	int val = !scarlett2_autogain_is_running(private);
 	int i;
 
-	scarlett2_set_ctl_access(private->input_select_ctl, val);
-	for (i = 0; i < info->gain_input_count / 2; i++)
-		scarlett2_set_ctl_access(private->input_link_ctls[i], val);
-	for (i = 0; i < info->gain_input_count; i++) {
+	if (scarlett2_has_config_item(private,
+				      SCARLETT2_CONFIG_INPUT_SELECT_SWITCH))
+		scarlett2_set_ctl_access(private->input_select_ctl, val);
+	if (scarlett2_has_config_item(private,
+				      SCARLETT2_CONFIG_INPUT_LINK_SWITCH))
+		for (i = 0; i < info->gain_input_count / 2; i++)
+			scarlett2_set_ctl_access(private->input_link_ctls[i],
+						 val);
+	for (i = 0; i < info->gain_input_count; i++)
 		scarlett2_set_ctl_access(private->input_gain_ctls[i], val);
+	for (i = 0; i < info->safe_input_count; i++)
 		scarlett2_set_ctl_access(private->safe_ctls[i], val);
-	}
 	for (i = 0; i < info->level_input_count; i++)
 		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);
+	for (i = 0; i < info->dsp_input_count; i++)
+		scarlett2_set_ctl_access(private->dsp_ctls[i], val);
+
+	for (i = 0; i < SCARLETT2_AG_TARGET_COUNT; i++)
+		if (scarlett2_has_config_item(private,
+					      scarlett2_ag_target_configs[i]))
+			scarlett2_set_ctl_access(
+				private->ag_target_ctls[i], val);
 }
 
 /* Notify of access mode change for all controls read-only while
@@ -2936,26 +3474,42 @@ static void scarlett2_autogain_notify_access(struct usb_mixer_interface *mixer)
 	const struct scarlett2_device_info *info = private->info;
 	int i;
 
-	snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO,
-		       &private->input_select_ctl->id);
-	for (i = 0; i < info->gain_input_count / 2; i++)
+	if (scarlett2_has_config_item(private,
+				      SCARLETT2_CONFIG_INPUT_SELECT_SWITCH))
 		snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO,
-			       &private->input_link_ctls[i]->id);
-	for (i = 0; i < info->gain_input_count; i++) {
+			       &private->input_select_ctl->id);
+	if (scarlett2_has_config_item(private,
+				      SCARLETT2_CONFIG_INPUT_LINK_SWITCH))
+		for (i = 0; i < info->gain_input_count / 2; i++)
+			snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO,
+				       &private->input_link_ctls[i]->id);
+	for (i = 0; i < info->gain_input_count; i++)
 		snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO,
 			       &private->input_gain_ctls[i]->id);
+	for (i = 0; i < info->safe_input_count; i++)
 		snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO,
 			       &private->safe_ctls[i]->id);
-	}
 	for (i = 0; i < info->level_input_count; i++)
 		snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO,
 			       &private->level_ctls[i]->id);
 	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->dsp_input_count; i++)
+		snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO,
+			       &private->dsp_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);
+
+	for (i = 0; i < SCARLETT2_AG_TARGET_COUNT; i++)
+		if (scarlett2_has_config_item(private,
+					      scarlett2_ag_target_configs[i]))
+			snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO,
+				       &private->ag_target_ctls[i]->id);
 }
 
 /* Call scarlett2_update_autogain() and
@@ -3124,10 +3678,13 @@ unlock:
 static int scarlett2_autogain_status_ctl_info(
 	struct snd_kcontrol *kctl, struct snd_ctl_elem_info *uinfo)
 {
+	struct usb_mixer_elem_info *elem = kctl->private_data;
+	struct scarlett2_data *private = elem->head.mixer->private_data;
+
 	return snd_ctl_enum_info(
 		uinfo, 1,
-		ARRAY_SIZE(scarlett2_autogain_status_texts),
-		scarlett2_autogain_status_texts);
+		private->num_autogain_status_texts,
+		private->config_set->autogain_status_texts);
 }
 
 static const struct snd_kcontrol_new scarlett2_autogain_switch_ctl = {
@@ -3146,6 +3703,122 @@ static const struct snd_kcontrol_new scarlett2_autogain_status_ctl = {
 	.get  = scarlett2_autogain_status_ctl_get,
 };
 
+/*** Autogain Target Controls ***/
+
+static int scarlett2_ag_target_ctl_info(
+	struct snd_kcontrol *kctl, struct snd_ctl_elem_info *uinfo)
+{
+	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;
+
+	mutex_lock(&private->data_mutex);
+
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
+	err = scarlett2_check_autogain_updated(mixer);
+	if (err < 0)
+		goto unlock;
+
+	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+	uinfo->count = 1;
+	uinfo->value.integer.min = SCARLETT2_AG_TARGET_MIN;
+	uinfo->value.integer.max = 0;
+	uinfo->value.integer.step = 1;
+
+unlock:
+	mutex_unlock(&private->data_mutex);
+	return err;
+}
+
+static int scarlett2_ag_target_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->autogain_updated) {
+		err = scarlett2_update_autogain(mixer);
+		if (err < 0)
+			goto unlock;
+	}
+
+	ucontrol->value.integer.value[0] = private->ag_targets[elem->control];
+
+unlock:
+	mutex_unlock(&private->data_mutex);
+	return err;
+}
+
+static int scarlett2_ag_target_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->ag_targets[index];
+	val = clamp(ucontrol->value.integer.value[0],
+		    (long)SCARLETT2_AG_TARGET_MIN, 0L);
+
+	if (oval == val)
+		goto unlock;
+
+	private->ag_targets[index] = val;
+
+	/* Send new value to the device */
+	err = scarlett2_usb_set_config(
+		mixer, scarlett2_ag_target_configs[index], 1, -val);
+	if (err == 0)
+		err = 1;
+
+unlock:
+	mutex_unlock(&private->data_mutex);
+	return err;
+}
+
+static const DECLARE_TLV_DB_MINMAX(
+	db_scale_ag_target, SCARLETT2_AG_TARGET_MIN * 100, 0
+);
+
+static const struct snd_kcontrol_new scarlett2_ag_target_ctl = {
+	.iface = SNDRV_CTL_ELEM_IFACE_CARD,
+	.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
+		  SNDRV_CTL_ELEM_ACCESS_TLV_READ,
+	.name = "",
+	.info = scarlett2_ag_target_ctl_info,
+	.get  = scarlett2_ag_target_ctl_get,
+	.put  = scarlett2_ag_target_ctl_put,
+	.tlv = { .p = db_scale_ag_target }
+};
+
 /*** Input Select Control ***/
 
 static int scarlett2_update_input_select(struct usb_mixer_interface *mixer)
@@ -3157,7 +3830,9 @@ static int scarlett2_update_input_select(struct usb_mixer_interface *mixer)
 
 	private->input_select_updated = 0;
 
-	if (!link_count)
+	if (!scarlett2_has_config_item(private,
+				       SCARLETT2_CONFIG_INPUT_SELECT_SWITCH) ||
+	    !link_count)
 		return 0;
 
 	err = scarlett2_usb_get_config(
@@ -3545,10 +4220,6 @@ unlock:
 	return err;
 }
 
-static const DECLARE_TLV_DB_MINMAX(
-	db_scale_scarlett2_gain, 0, SCARLETT2_MAX_GAIN_DB * 100
-);
-
 static const struct snd_kcontrol_new scarlett2_input_gain_ctl = {
 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
 	.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
@@ -3558,7 +4229,6 @@ static const struct snd_kcontrol_new scarlett2_input_gain_ctl = {
 	.get  = scarlett2_input_gain_ctl_get,
 	.put  = scarlett2_input_gain_ctl_put,
 	.private_value = 0, /* max value */
-	.tlv = { .p = db_scale_scarlett2_gain }
 };
 
 /*** Safe Controls ***/
@@ -3570,12 +4240,12 @@ static int scarlett2_update_input_safe(struct usb_mixer_interface *mixer)
 
 	private->input_safe_updated = 0;
 
-	if (!info->gain_input_count)
+	if (!info->safe_input_count)
 		return 0;
 
 	return scarlett2_usb_get_config(
 		mixer, SCARLETT2_CONFIG_SAFE_SWITCH,
-		info->gain_input_count, private->safe_switch);
+		info->safe_input_count, private->safe_switch);
 }
 
 static int scarlett2_safe_ctl_get(struct snd_kcontrol *kctl,
@@ -4567,6 +5237,670 @@ static const struct snd_kcontrol_new scarlett2_air_ctl[2] = {
 	}
 };
 
+/*** DSP Switch Control ***/
+
+static int scarlett2_update_input_dsp(struct usb_mixer_interface *mixer)
+{
+	struct scarlett2_data *private = mixer->private_data;
+	const struct scarlett2_device_info *info = private->info;
+
+	private->input_dsp_updated = 0;
+
+	if (!info->dsp_input_count)
+		return 0;
+
+	return scarlett2_usb_get_config(
+		mixer, SCARLETT2_CONFIG_DSP_SWITCH,
+		info->dsp_input_count, private->dsp_switch);
+}
+
+static int scarlett2_dsp_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_dsp_updated) {
+		err = scarlett2_update_input_dsp(mixer);
+		if (err < 0)
+			goto unlock;
+	}
+	ucontrol->value.integer.value[0] = private->dsp_switch[elem->control];
+
+unlock:
+	mutex_unlock(&private->data_mutex);
+	return err;
+}
+
+static int scarlett2_dsp_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->dsp_switch[index];
+	val = ucontrol->value.integer.value[0];
+
+	if (oval == val)
+		goto unlock;
+
+	private->dsp_switch[index] = val;
+
+	/* Send switch change to the device */
+	err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_DSP_SWITCH,
+				       index, val);
+	if (err == 0)
+		err = 1;
+
+unlock:
+	mutex_unlock(&private->data_mutex);
+	return err;
+}
+
+static const struct snd_kcontrol_new scarlett2_dsp_ctl = {
+	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+	.name = "",
+	.info = scarlett2_autogain_disables_ctl_info,
+	.get  = scarlett2_dsp_ctl_get,
+	.put  = scarlett2_dsp_ctl_put,
+};
+
+/*** DSP Compressor Parameter Controls ***/
+
+static int scarlett2_update_compressor_values(struct usb_mixer_interface *mixer)
+{
+	struct scarlett2_data *private = mixer->private_data;
+	const struct scarlett2_device_info *info = private->info;
+	int err, i, j;
+
+	if (!info->dsp_input_count)
+		return 0;
+
+	err = scarlett2_usb_get_config(
+		mixer, SCARLETT2_CONFIG_COMPRESSOR_PARAMS,
+		SCARLETT2_COMPRESSOR_PARAM_COUNT * info->dsp_input_count,
+		private->compressor_values);
+
+	if (err < 0)
+		return err;
+
+	for (i = 0; i < SCARLETT2_COMPRESSOR_PARAM_COUNT; i++) {
+		const struct compressor_param *param = &compressor_params[i];
+
+		for (j = 0; j < info->dsp_input_count; j++) {
+			int idx = i + j * SCARLETT2_COMPRESSOR_PARAM_COUNT;
+			int val = private->compressor_values[idx];
+
+			val >>= param->scale_bits;
+			val = clamp(val, param->min, param->max);
+			private->compressor_values[idx] = val;
+		}
+	}
+
+	return 0;
+}
+
+static int scarlett2_compressor_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;
+
+	ucontrol->value.integer.value[0] =
+		private->compressor_values[elem->control];
+	return 0;
+}
+
+static int scarlett2_compressor_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 channel = index / SCARLETT2_COMPRESSOR_PARAM_COUNT;
+	int param_index = index % SCARLETT2_COMPRESSOR_PARAM_COUNT;
+	int oval, val, err;
+	s32 scaled_val;
+
+	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->compressor_values[index];
+	val = ucontrol->value.integer.value[0];
+	if (oval == val)
+		goto unlock;
+
+	private->compressor_values[index] = val;
+
+	const struct compressor_param *param = &compressor_params[param_index];
+
+	scaled_val = val << param->scale_bits;
+
+	/* Send change to the device */
+
+	/* The channel needs to be put in the parameter buffer index
+	 * field (param_buf_addr + 1); the value field isn't used in
+	 * this case.
+	 */
+	err = scarlett2_usb_set_data(
+		mixer, private->config_set->param_buf_addr + 1, 1, channel);
+	if (err < 0)
+		goto unlock;
+
+	err = scarlett2_usb_set_config(
+		mixer, SCARLETT2_CONFIG_COMPRESSOR_PARAMS, index, scaled_val);
+	if (err < 0)
+		goto unlock;
+
+	if (err == 0)
+		err = 1;
+
+unlock:
+	mutex_unlock(&private->data_mutex);
+	return err;
+}
+
+static int scarlett2_compressor_ctl_info(
+	struct snd_kcontrol *kctl, struct snd_ctl_elem_info *uinfo)
+{
+	struct usb_mixer_elem_info *elem = kctl->private_data;
+	int control = elem->control % SCARLETT2_COMPRESSOR_PARAM_COUNT;
+
+	uinfo->type = compressor_params[control].type;
+	uinfo->count = 1;
+	uinfo->value.integer.min = compressor_params[control].min;
+	uinfo->value.integer.max = compressor_params[control].max;
+	uinfo->value.integer.step = 1;
+	return 0;
+}
+
+static const struct snd_kcontrol_new scarlett2_compressor_ctl = {
+	.iface = SNDRV_CTL_ELEM_IFACE_CARD,
+	.name = "",
+	.info = scarlett2_compressor_ctl_info,
+	.get  = scarlett2_compressor_ctl_get,
+	.put  = scarlett2_compressor_ctl_put,
+};
+
+/*** DSP Pre-Compressor and PEQ Filter Controls ***/
+
+static int scarlett2_precomp_flt_switch_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;
+
+	ucontrol->value.integer.value[0] = private->precomp_flt_switch[elem->control];
+
+	return 0;
+}
+
+static int scarlett2_peq_flt_switch_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;
+
+	ucontrol->value.integer.value[0] =
+		private->peq_flt_switch[elem->control];
+
+	return 0;
+}
+
+static int scarlett2_precomp_flt_switch_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 oval, val, err = 0;
+
+	mutex_lock(&private->data_mutex);
+
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
+	oval = private->precomp_flt_switch[elem->control];
+	val = ucontrol->value.integer.value[0];
+
+	if (oval == val)
+		goto unlock;
+
+	private->precomp_flt_switch[elem->control] = val;
+
+	/* Send change to the device */
+	err = scarlett2_usb_set_config(
+		mixer, SCARLETT2_CONFIG_PRECOMP_FLT_SWITCH,
+		elem->control, val);
+	if (err == 0)
+		err = 1;
+
+unlock:
+	mutex_unlock(&private->data_mutex);
+	return err;
+}
+
+static int scarlett2_peq_flt_switch_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 oval, val, err = 0;
+
+	mutex_lock(&private->data_mutex);
+
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
+	oval = private->peq_flt_switch[elem->control];
+	val = ucontrol->value.integer.value[0];
+
+	if (oval == val)
+		goto unlock;
+
+	private->peq_flt_switch[elem->control] = val;
+
+	/* Send change to the device */
+	err = scarlett2_usb_set_config(
+		mixer, SCARLETT2_CONFIG_PEQ_FLT_SWITCH,
+		elem->control, val);
+	if (err == 0)
+		err = 1;
+
+unlock:
+	mutex_unlock(&private->data_mutex);
+	return err;
+}
+
+static const struct snd_kcontrol_new scarlett2_precomp_flt_switch_ctl = {
+	.iface = SNDRV_CTL_ELEM_IFACE_CARD,
+	.name = "",
+	.info = snd_ctl_boolean_mono_info,
+	.get  = scarlett2_precomp_flt_switch_ctl_get,
+	.put  = scarlett2_precomp_flt_switch_ctl_put,
+};
+
+static const struct snd_kcontrol_new scarlett2_peq_flt_switch_ctl = {
+	.iface = SNDRV_CTL_ELEM_IFACE_CARD,
+	.name = "",
+	.info = snd_ctl_boolean_mono_info,
+	.get  = scarlett2_peq_flt_switch_ctl_get,
+	.put  = scarlett2_peq_flt_switch_ctl_put,
+};
+
+static int scarlett2_update_filter_values(struct usb_mixer_interface *mixer)
+{
+	struct scarlett2_data *private = mixer->private_data;
+	const struct scarlett2_device_info *info = private->info;
+	int err, i, j, k, src_idx, dst_idx;
+	s32 peq_flt_values[SCARLETT2_DSP_SWITCH_MAX *
+			   SCARLETT2_PEQ_FLT_SLOTS_MAX *
+			   SCARLETT2_BIQUAD_COEFFS];
+
+	if (!info->dsp_input_count)
+		return 0;
+
+	/* Get filter switch values */
+	err = scarlett2_usb_get_config(
+		mixer, SCARLETT2_CONFIG_PRECOMP_FLT_SWITCH,
+		info->dsp_input_count, private->precomp_flt_switch);
+	if (err < 0)
+		return err;
+
+	err = scarlett2_usb_get_config(
+		mixer, SCARLETT2_CONFIG_PEQ_FLT_SWITCH,
+		info->dsp_input_count * info->peq_flt_count,
+		private->peq_flt_switch);
+	if (err < 0)
+		return err;
+
+	/* Get pre-compressor filter values directly */
+	err = scarlett2_usb_get_config(
+		mixer, SCARLETT2_CONFIG_PRECOMP_FLT_PARAMS,
+		info->dsp_input_count *
+			info->precomp_flt_count *
+			SCARLETT2_BIQUAD_COEFFS,
+		private->precomp_flt_values);
+
+	if (err < 0)
+		return err;
+
+	/* PEQ filter values need to be copied via buffer because of
+	 * padding after peq_flt_count up to peq_flt_total_count
+	 */
+	err = scarlett2_usb_get_config(
+		mixer, SCARLETT2_CONFIG_PEQ_FLT_PARAMS,
+		info->dsp_input_count *
+			info->peq_flt_total_count *
+			SCARLETT2_BIQUAD_COEFFS,
+		peq_flt_values);
+
+	for (i = 0, dst_idx = 0; i < info->dsp_input_count; i++) {
+		src_idx = i *
+			  info->peq_flt_total_count *
+			  SCARLETT2_BIQUAD_COEFFS;
+		for (j = 0; j < info->peq_flt_count; j++)
+			for (k = 0;
+			     k < SCARLETT2_BIQUAD_COEFFS;
+			     k++, src_idx++, dst_idx++)
+				private->peq_flt_values[dst_idx] =
+					peq_flt_values[src_idx];
+	}
+
+	return 0;
+}
+
+static int scarlett2_precomp_flt_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 i, idx;
+
+	for (i = 0, idx = elem->control * SCARLETT2_BIQUAD_COEFFS;
+	     i < SCARLETT2_BIQUAD_COEFFS;
+	     i++, idx++)
+		ucontrol->value.integer.value[i] =
+			private->precomp_flt_values[idx];
+
+	return 0;
+}
+
+static int scarlett2_peq_flt_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 i, idx;
+
+	for (i = 0, idx = elem->control * SCARLETT2_BIQUAD_COEFFS;
+	     i < SCARLETT2_BIQUAD_COEFFS;
+	     i++, idx++)
+		ucontrol->value.integer.value[i] =
+			private->peq_flt_values[idx];
+
+	return 0;
+}
+
+static int scarlett2_precomp_flt_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 * SCARLETT2_BIQUAD_COEFFS;
+	int i, 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;
+
+	/* Check if any of the values have changed; if not, return */
+	for (i = 0; i < SCARLETT2_BIQUAD_COEFFS; i++) {
+		oval = private->precomp_flt_values[index + i];
+		val = ucontrol->value.integer.value[i];
+		if (oval != val)
+			break;
+	}
+
+	if (i == SCARLETT2_BIQUAD_COEFFS)
+		goto unlock;
+
+	/* Update the values */
+	for (i = 0; i < SCARLETT2_BIQUAD_COEFFS; i++)
+		private->precomp_flt_values[index + i] =
+			ucontrol->value.integer.value[i];
+
+	/* Send change to the device */
+	err = scarlett2_usb_set_data(
+		mixer, private->config_set->param_buf_addr, 1, index);
+	if (err < 0)
+		goto unlock;
+
+	err = scarlett2_usb_set_config_buf(
+		mixer, SCARLETT2_CONFIG_PRECOMP_FLT_PARAMS,
+		index, SCARLETT2_BIQUAD_COEFFS,
+		&private->precomp_flt_values[index]);
+
+	if (err == 0)
+		err = 1;
+
+unlock:
+	mutex_unlock(&private->data_mutex);
+	return err;
+}
+
+static int scarlett2_peq_flt_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;
+	const struct scarlett2_device_info *info = private->info;
+
+	int src_index = elem->control * SCARLETT2_BIQUAD_COEFFS;
+	int dst_index = (
+		elem->control /
+		info->peq_flt_count *
+		info->peq_flt_total_count +
+		elem->control % info->peq_flt_count
+	) * SCARLETT2_BIQUAD_COEFFS;
+	int i, 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;
+
+	/* Check if any of the values have changed; if not, return */
+	for (i = 0; i < SCARLETT2_BIQUAD_COEFFS; i++) {
+		oval = private->peq_flt_values[src_index + i];
+		val = ucontrol->value.integer.value[i];
+		if (oval != val)
+			break;
+	}
+
+	if (i == SCARLETT2_BIQUAD_COEFFS)
+		goto unlock;
+
+	/* Update the values */
+	for (i = 0; i < SCARLETT2_BIQUAD_COEFFS; i++)
+		private->peq_flt_values[src_index + i] =
+			ucontrol->value.integer.value[i];
+
+	/* Send change to the device */
+	err = scarlett2_usb_set_data(
+		mixer, private->config_set->param_buf_addr, 1, dst_index);
+	if (err < 0)
+		goto unlock;
+
+	err = scarlett2_usb_set_config_buf(
+		mixer, SCARLETT2_CONFIG_PEQ_FLT_PARAMS,
+		dst_index, SCARLETT2_BIQUAD_COEFFS,
+		&private->peq_flt_values[src_index]);
+
+	if (err == 0)
+		err = 1;
+
+unlock:
+	mutex_unlock(&private->data_mutex);
+	return err;
+}
+
+static int scarlett2_flt_ctl_info(
+	struct snd_kcontrol *kctl, struct snd_ctl_elem_info *uinfo)
+{
+	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+	uinfo->count = SCARLETT2_BIQUAD_COEFFS;
+	uinfo->value.integer.min = INT_MIN;
+	uinfo->value.integer.max = INT_MAX;
+	uinfo->value.integer.step = 1;
+	return 0;
+}
+
+static const struct snd_kcontrol_new scarlett2_precomp_flt_ctl = {
+	.iface = SNDRV_CTL_ELEM_IFACE_CARD,
+	.name = "",
+	.info = scarlett2_flt_ctl_info,
+	.get  = scarlett2_precomp_flt_ctl_get,
+	.put  = scarlett2_precomp_flt_ctl_put,
+};
+
+static const struct snd_kcontrol_new scarlett2_peq_flt_ctl = {
+	.iface = SNDRV_CTL_ELEM_IFACE_CARD,
+	.name = "",
+	.info = scarlett2_flt_ctl_info,
+	.get  = scarlett2_peq_flt_ctl_get,
+	.put  = scarlett2_peq_flt_ctl_put,
+};
+
+/*** 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)
@@ -5406,6 +6740,69 @@ static int scarlett2_add_line_out_ctls(struct usb_mixer_interface *mixer)
 
 /*** Create the analogue input controls ***/
 
+static int scarlett2_add_dsp_ctls(struct usb_mixer_interface *mixer, int i)
+{
+	struct scarlett2_data *private = mixer->private_data;
+	const struct scarlett2_device_info *info = private->info;
+	int j, err;
+	char s[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
+	const char *compr_fmt = "Line In %d Compressor %s";
+	const char *flt_switch_fmt = "Line In %d %s Filter Enable";
+	const char *flt_fmt = "Line In %d %s Coefficients %d";
+
+	/* Add compressor controls */
+	for (j = 0; j < SCARLETT2_COMPRESSOR_PARAM_COUNT; j++) {
+		const struct compressor_param *param = &compressor_params[j];
+		int idx = i * SCARLETT2_COMPRESSOR_PARAM_COUNT + j;
+
+		scnprintf(s, sizeof(s), compr_fmt, i + 1, param->name);
+		err = scarlett2_add_new_ctl(
+			mixer, &scarlett2_compressor_ctl,
+			i * SCARLETT2_COMPRESSOR_PARAM_COUNT + j,
+			1, s, &private->compressor_ctls[idx]);
+		if (err < 0)
+			return err;
+	}
+
+	/* Add filter enable controls */
+	scnprintf(s, sizeof(s), flt_switch_fmt, i + 1, "Pre-Comp");
+	err = scarlett2_add_new_ctl(
+		mixer, &scarlett2_precomp_flt_switch_ctl,
+		i, 1, s, &private->precomp_flt_switch_ctls[i]);
+	if (err < 0)
+		return err;
+
+	scnprintf(s, sizeof(s), flt_switch_fmt, i + 1, "PEQ");
+	err = scarlett2_add_new_ctl(
+		mixer, &scarlett2_peq_flt_switch_ctl,
+		i, 1, s, &private->peq_flt_switch_ctls[i]);
+	if (err < 0)
+		return err;
+
+	/* Add filter coefficient controls */
+	for (j = 0; j < info->precomp_flt_count; j++) {
+		scnprintf(s, sizeof(s), flt_fmt, i + 1, "Pre-Comp", j + 1);
+		err = scarlett2_add_new_ctl(
+			mixer, &scarlett2_precomp_flt_ctl,
+			i * info->precomp_flt_count + j,
+			1, s, &private->precomp_flt_switch_ctls[j]);
+		if (err < 0)
+			return err;
+	}
+
+	for (j = 0; j < info->peq_flt_count; j++) {
+		scnprintf(s, sizeof(s), flt_fmt, i + 1, "PEQ", j + 1);
+		err = scarlett2_add_new_ctl(
+			mixer, &scarlett2_peq_flt_ctl,
+			i * info->peq_flt_count + j,
+			1, s, &private->peq_flt_switch_ctls[j]);
+		if (err < 0)
+			return err;
+	}
+
+	return 0;
+}
+
 static int scarlett2_add_line_in_ctls(struct usb_mixer_interface *mixer)
 {
 	struct scarlett2_data *private = mixer->private_data;
@@ -5445,6 +6842,29 @@ static int scarlett2_add_line_in_ctls(struct usb_mixer_interface *mixer)
 			return err;
 	}
 
+	/* Add input DSP controls */
+	for (i = 0; i < info->dsp_input_count; i++) {
+		scnprintf(s, sizeof(s), fmt, i + 1, "DSP", "Switch");
+		err = scarlett2_add_new_ctl(mixer, &scarlett2_dsp_ctl,
+					    i, 1, s, &private->dsp_ctls[i]);
+		if (err < 0)
+			return err;
+
+		err = scarlett2_add_dsp_ctls(mixer, i);
+		if (err < 0)
+			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++) {
@@ -5481,58 +6901,81 @@ static int scarlett2_add_line_in_ctls(struct usb_mixer_interface *mixer)
 			return err;
 	}
 
-	/* Add software-controllable input gain controls */
-	if (info->gain_input_count) {
+	/* Add input select/link controls */
+	if (scarlett2_has_config_item(private,
+				      SCARLETT2_CONFIG_INPUT_SELECT_SWITCH)) {
 		err = scarlett2_add_new_ctl(
 			mixer, &scarlett2_input_select_ctl, 0, 1,
 			"Input Select Capture Enum",
 			&private->input_select_ctl);
 		if (err < 0)
 			return err;
+	}
 
-		for (i = 0; i < info->gain_input_count; i++) {
-			if (i % 2) {
-				scnprintf(s, sizeof(s),
-					  "Line In %d-%d Link Capture Switch",
-					  i, i + 1);
-				err = scarlett2_add_new_ctl(
-					mixer, &scarlett2_input_link_ctl,
-					i / 2, 1, s,
-					&private->input_link_ctls[i / 2]);
-				if (err < 0)
-					return err;
-			}
-
-			scnprintf(s, sizeof(s), fmt, i + 1,
-				  "Gain", "Volume");
+	if (scarlett2_has_config_item(private,
+				      SCARLETT2_CONFIG_INPUT_LINK_SWITCH)) {
+		for (i = 0; i < info->gain_input_count / 2; i++) {
+			scnprintf(s, sizeof(s),
+				  "Line In %d-%d Link Capture Switch",
+				  (i * 2) + 1, (i * 2) + 2);
 			err = scarlett2_add_new_ctl(
-				mixer, &scarlett2_input_gain_ctl,
-				i, 1, s, &private->input_gain_ctls[i]);
+				mixer, &scarlett2_input_link_ctl,
+				i, 1, s, &private->input_link_ctls[i]);
 			if (err < 0)
 				return err;
+		}
+	}
 
-			scnprintf(s, sizeof(s), fmt, i + 1,
-				  "Autogain", "Switch");
-			err = scarlett2_add_new_ctl(
-				mixer, &scarlett2_autogain_switch_ctl,
-				i, 1, s, &private->autogain_ctls[i]);
-			if (err < 0)
-				return err;
+	/* Add software-controllable input gain controls */
+	for (i = 0; i < info->gain_input_count; i++) {
+		scnprintf(s, sizeof(s), fmt, i + 1,
+			  "Gain", "Volume");
+		err = scarlett2_add_new_ctl(
+			mixer, &scarlett2_input_gain_ctl,
+			i, 1, s, &private->input_gain_ctls[i]);
+		if (err < 0)
+			return err;
+		private->input_gain_ctls[i]->tlv.p =
+			private->config_set->input_gain_tlv;
 
-			scnprintf(s, sizeof(s), fmt, i + 1,
-				  "Autogain Status", "Enum");
-			err = scarlett2_add_new_ctl(
-				mixer, &scarlett2_autogain_status_ctl,
-				i, 1, s, &private->autogain_status_ctls[i]);
+		scnprintf(s, sizeof(s), fmt, i + 1,
+			  "Autogain", "Switch");
+		err = scarlett2_add_new_ctl(
+			mixer, &scarlett2_autogain_switch_ctl,
+			i, 1, s, &private->autogain_ctls[i]);
+		if (err < 0)
+			return err;
+
+		scnprintf(s, sizeof(s), fmt, i + 1,
+			  "Autogain Status", "Enum");
+		err = scarlett2_add_new_ctl(
+			mixer, &scarlett2_autogain_status_ctl,
+			i, 1, s, &private->autogain_status_ctls[i]);
+	}
+
+	/* Add autogain target controls */
+	for (i = 0; i < SCARLETT2_AG_TARGET_COUNT; i++)
+		if (scarlett2_has_config_item(private,
+					      scarlett2_ag_target_configs[i])) {
 
-			scnprintf(s, sizeof(s), fmt, i + 1,
-				  "Safe", "Switch");
+			scnprintf(s, sizeof(s), "Autogain %s Target",
+				  scarlett2_ag_target_names[i]);
 			err = scarlett2_add_new_ctl(
-				mixer, &scarlett2_safe_ctl,
-				i, 1, s, &private->safe_ctls[i]);
+				mixer, &scarlett2_ag_target_ctl,
+				i, 1, s, &private->ag_target_ctls[i]);
 			if (err < 0)
 				return err;
 		}
+
+	/* Add safe-mode input switch controls */
+	for (i = 0; i < info->safe_input_count; i++) {
+		scnprintf(s, sizeof(s), fmt, i + 1,
+			  "Safe", "Switch");
+		err = scarlett2_add_new_ctl(
+			mixer, &scarlett2_safe_ctl,
+			i, 1, s, &private->safe_ctls[i]);
+		if (err < 0)
+			return err;
 	}
 
 	/* Add PCM Input Switch control */
@@ -6383,413 +7826,238 @@ static int scarlett2_add_power_status_ctl(struct usb_mixer_interface *mixer)
 				     &private->power_status_ctl);
 }
 
-/*** Cleanup/Suspend Callbacks ***/
+/*** Bluetooth Volume ***/
 
-static void scarlett2_private_free(struct usb_mixer_interface *mixer)
-{
-	struct scarlett2_data *private = mixer->private_data;
-
-	cancel_delayed_work_sync(&private->work);
-	kfree(private);
-	mixer->private_data = NULL;
-}
-
-static void scarlett2_private_suspend(struct usb_mixer_interface *mixer)
+static int scarlett2_update_bluetooth_volume(struct usb_mixer_interface *mixer)
 {
 	struct scarlett2_data *private = mixer->private_data;
+	int err;
 
-	if (cancel_delayed_work_sync(&private->work))
-		scarlett2_config_save(private->mixer);
-}
-
-/*** Initialisation ***/
-
-static void scarlett2_count_io(struct scarlett2_data *private)
-{
-	const struct scarlett2_device_info *info = private->info;
-	const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
-	int port_type, srcs = 0, dsts = 0;
-
-	/* Count the number of mux sources and destinations */
-	for (port_type = 0;
-	     port_type < SCARLETT2_PORT_TYPE_COUNT;
-	     port_type++) {
-		srcs += port_count[port_type][SCARLETT2_PORT_IN];
-		dsts += port_count[port_type][SCARLETT2_PORT_OUT];
-	}
-
-	private->num_mux_srcs = srcs;
-	private->num_mux_dsts = dsts;
-
-	/* Mixer inputs are mux outputs and vice versa.
-	 * Scarlett Gen 4 DSP I/O uses SCARLETT2_PORT_TYPE_MIX but
-	 * doesn't have mixer controls.
-	 */
-	private->num_mix_in =
-		port_count[SCARLETT2_PORT_TYPE_MIX][SCARLETT2_PORT_OUT] -
-			info->dsp_count;
+	private->bluetooth_updated = 0;
 
-	private->num_mix_out =
-		port_count[SCARLETT2_PORT_TYPE_MIX][SCARLETT2_PORT_IN] -
-			info->dsp_count;
+	if (!private->info->has_bluetooth)
+		return 0;
 
-	/* Number of analogue line outputs */
-	private->num_line_out =
-		port_count[SCARLETT2_PORT_TYPE_ANALOGUE][SCARLETT2_PORT_OUT];
+	err = scarlett2_usb_get_config(mixer,
+				       SCARLETT2_CONFIG_BLUETOOTH_VOLUME,
+				       1, &private->bluetooth_volume);
+	if (err < 0)
+		return err;
 
-	/* Number of monitor mix controls */
-	private->num_monitor_mix_ctls =
-		info->direct_monitor * 2 * private->num_mix_in;
+	return 0;
 }
 
-/* Look through the interface descriptors for the Focusrite Control
- * interface (bInterfaceClass = 255 Vendor Specific Class) and set
- * bInterfaceNumber, bEndpointAddress, wMaxPacketSize, and bInterval
- * in private
- */
-static int scarlett2_find_fc_interface(struct usb_device *dev,
-				       struct scarlett2_data *private)
+static int scarlett2_bluetooth_volume_ctl_get(struct snd_kcontrol *kctl,
+					     struct snd_ctl_elem_value *ucontrol)
 {
-	struct usb_host_config *config = dev->actconfig;
-	int i;
+	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;
 
-	for (i = 0; i < config->desc.bNumInterfaces; i++) {
-		struct usb_interface *intf = config->interface[i];
-		struct usb_interface_descriptor *desc =
-			&intf->altsetting[0].desc;
-		struct usb_endpoint_descriptor *epd;
+	mutex_lock(&private->data_mutex);
 
-		if (desc->bInterfaceClass != 255)
-			continue;
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
 
-		epd = get_endpoint(intf->altsetting, 0);
-		private->bInterfaceNumber = desc->bInterfaceNumber;
-		private->bEndpointAddress = epd->bEndpointAddress &
-			USB_ENDPOINT_NUMBER_MASK;
-		private->wMaxPacketSize = le16_to_cpu(epd->wMaxPacketSize);
-		private->bInterval = epd->bInterval;
-		return 0;
+	if (private->bluetooth_updated) {
+		err = scarlett2_update_bluetooth_volume(mixer);
+		if (err < 0)
+			goto unlock;
 	}
+	ucontrol->value.integer.value[0] = private->bluetooth_volume;
 
-	return -EINVAL;
+unlock:
+	mutex_unlock(&private->data_mutex);
+	return err;
 }
 
-/* Initialise private data */
-static int scarlett2_init_private(struct usb_mixer_interface *mixer,
-				  const struct scarlett2_device_entry *entry)
+static int scarlett2_bluetooth_volume_ctl_put(struct snd_kcontrol *kctl,
+					     struct snd_ctl_elem_value *ucontrol)
 {
-	struct scarlett2_data *private =
-		kzalloc(sizeof(struct scarlett2_data), GFP_KERNEL);
+	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 oval, val, err = 0;
 
-	if (!private)
-		return -ENOMEM;
+	mutex_lock(&private->data_mutex);
 
-	mutex_init(&private->usb_mutex);
-	mutex_init(&private->data_mutex);
-	INIT_DELAYED_WORK(&private->work, scarlett2_config_save_work);
+	if (private->hwdep_in_use) {
+		err = -EBUSY;
+		goto unlock;
+	}
 
-	mixer->private_data = private;
-	mixer->private_free = scarlett2_private_free;
-	mixer->private_suspend = scarlett2_private_suspend;
+	oval = private->bluetooth_volume;
+	val = clamp(ucontrol->value.integer.value[0],
+		    0L, (long)SCARLETT2_MAX_BLUETOOTH_VOLUME);
 
-	private->info = entry->info;
-	private->config_set = entry->info->config_set;
-	private->series_name = entry->series_name;
-	scarlett2_count_io(private);
-	private->scarlett2_seq = 0;
-	private->mixer = mixer;
+	if (oval == val)
+		goto unlock;
 
-	return scarlett2_find_fc_interface(mixer->chip->dev, private);
+	private->bluetooth_volume = val;
+	err = scarlett2_usb_set_config(mixer,
+				       SCARLETT2_CONFIG_BLUETOOTH_VOLUME,
+				       0, val);
+	if (err == 0)
+		err = 1;
+
+unlock:
+	mutex_unlock(&private->data_mutex);
+	return err;
 }
 
-/* Cargo cult proprietary initialisation sequence */
-static int scarlett2_usb_init(struct usb_mixer_interface *mixer)
+static int scarlett2_bluetooth_volume_ctl_info(
+	struct snd_kcontrol *kctl, struct snd_ctl_elem_info *uinfo)
 {
-	struct usb_device *dev = mixer->chip->dev;
-	struct scarlett2_data *private = mixer->private_data;
-	u8 step0_buf[24];
-	u8 step2_buf[84];
-	int err;
-
-	if (usb_pipe_type_check(dev, usb_sndctrlpipe(dev, 0)))
-		return -EINVAL;
-
-	/* step 0 */
-	err = scarlett2_usb_rx(dev, private->bInterfaceNumber,
-			       SCARLETT2_USB_CMD_INIT,
-			       step0_buf, sizeof(step0_buf));
-	if (err < 0)
-		return err;
-
-	/* step 1 */
-	private->scarlett2_seq = 1;
-	err = scarlett2_usb(mixer, SCARLETT2_USB_INIT_1, NULL, 0, NULL, 0);
-	if (err < 0)
-		return err;
-
-	/* step 2 */
-	private->scarlett2_seq = 1;
-	err = scarlett2_usb(mixer, SCARLETT2_USB_INIT_2,
-			    NULL, 0,
-			    step2_buf, sizeof(step2_buf));
-	if (err < 0)
-		return err;
-
-	/* extract 4-byte firmware version from step2_buf[8] */
-	private->firmware_version = le32_to_cpu(*(__le32 *)(step2_buf + 8));
-	usb_audio_info(mixer->chip,
-		       "Firmware version %d\n",
-		       private->firmware_version);
-
+	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+	uinfo->count = 1;
+	uinfo->value.integer.min = 0;
+	uinfo->value.integer.max = SCARLETT2_MAX_BLUETOOTH_VOLUME;
+	uinfo->value.integer.step = 1;
 	return 0;
 }
 
-/* Get the flash segment numbers for the App_Settings and App_Upgrade
- * segments and put them in the private data
- */
-static int scarlett2_get_flash_segment_nums(struct usb_mixer_interface *mixer)
+static const struct snd_kcontrol_new scarlett2_bluetooth_volume_ctl = {
+	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+	.name = "",
+	.info = scarlett2_bluetooth_volume_ctl_info,
+	.get  = scarlett2_bluetooth_volume_ctl_get,
+	.put  = scarlett2_bluetooth_volume_ctl_put,
+};
+
+static int scarlett2_add_bluetooth_volume_ctl(
+	struct usb_mixer_interface *mixer)
 {
 	struct scarlett2_data *private = mixer->private_data;
-	int err, count, i;
-
-	struct {
-		__le32 size;
-		__le32 count;
-		u8 unknown[8];
-	} __packed flash_info;
-
-	struct {
-		__le32 size;
-		__le32 flags;
-		char name[16];
-	} __packed segment_info;
 
-	err = scarlett2_usb(mixer, SCARLETT2_USB_INFO_FLASH,
-			    NULL, 0,
-			    &flash_info, sizeof(flash_info));
-	if (err < 0)
-		return err;
-
-	count = le32_to_cpu(flash_info.count);
-
-	/* sanity check count */
-	if (count < SCARLETT2_SEGMENT_NUM_MIN ||
-	    count > SCARLETT2_SEGMENT_NUM_MAX + 1) {
-		usb_audio_err(mixer->chip,
-			      "invalid flash segment count: %d\n", count);
-		return -EINVAL;
-	}
-
-	for (i = 0; i < count; i++) {
-		__le32 segment_num_req = cpu_to_le32(i);
-		int flash_segment_id;
-
-		err = scarlett2_usb(mixer, SCARLETT2_USB_INFO_SEGMENT,
-				    &segment_num_req, sizeof(segment_num_req),
-				    &segment_info, sizeof(segment_info));
-		if (err < 0) {
-			usb_audio_err(mixer->chip,
-				"failed to get flash segment info %d: %d\n",
-				i, err);
-			return err;
-		}
-
-		if (!strncmp(segment_info.name,
-			     SCARLETT2_SEGMENT_SETTINGS_NAME, 16))
-			flash_segment_id = SCARLETT2_SEGMENT_ID_SETTINGS;
-		else if (!strncmp(segment_info.name,
-				  SCARLETT2_SEGMENT_FIRMWARE_NAME, 16))
-			flash_segment_id = SCARLETT2_SEGMENT_ID_FIRMWARE;
-		else
-			continue;
-
-		private->flash_segment_nums[flash_segment_id] = i;
-		private->flash_segment_blocks[flash_segment_id] =
-			le32_to_cpu(segment_info.size) /
-				SCARLETT2_FLASH_BLOCK_SIZE;
-	}
-
-	/* segment 0 is App_Gold and we never want to touch that, so
-	 * use 0 as the "not-found" value
-	 */
-	if (!private->flash_segment_nums[SCARLETT2_SEGMENT_ID_SETTINGS]) {
-		usb_audio_err(mixer->chip,
-			      "failed to find flash segment %s\n",
-			      SCARLETT2_SEGMENT_SETTINGS_NAME);
-		return -EINVAL;
-	}
-	if (!private->flash_segment_nums[SCARLETT2_SEGMENT_ID_FIRMWARE]) {
-		usb_audio_err(mixer->chip,
-			      "failed to find flash segment %s\n",
-			      SCARLETT2_SEGMENT_FIRMWARE_NAME);
-		return -EINVAL;
-	}
+	if (!private->info->has_bluetooth)
+		return 0;
 
-	return 0;
+	/* Add Bluetooth volume control */
+	return scarlett2_add_new_ctl(mixer, &scarlett2_bluetooth_volume_ctl,
+				     0, 1, "Bluetooth Capture Volume",
+				     &private->bluetooth_volume_ctl);
 }
 
-/* Read configuration from the interface on start */
-static int scarlett2_read_configs(struct usb_mixer_interface *mixer)
+/*** S/PDIF Mode Controls ***/
+
+static int scarlett2_update_spdif_mode(struct usb_mixer_interface *mixer)
 {
 	struct scarlett2_data *private = mixer->private_data;
-	const struct scarlett2_device_info *info = private->info;
 	int err, i;
+	u8 mode;
+	const u8 *mode_values = private->info->spdif_mode_values;
 
-	if (scarlett2_has_config_item(private, SCARLETT2_CONFIG_MSD_SWITCH)) {
-		err = scarlett2_usb_get_config(
-			mixer, SCARLETT2_CONFIG_MSD_SWITCH,
-			1, &private->msd_switch);
-		if (err < 0)
-			return err;
-	}
-
-	if (private->firmware_version < info->min_firmware_version) {
-		usb_audio_err(mixer->chip,
-			      "Focusrite %s firmware version %d is too old; "
-			      "need %d",
-			      private->series_name,
-			      private->firmware_version,
-			      info->min_firmware_version);
-		return 0;
-	}
-
-	/* no other controls are created if MSD mode is on */
-	if (private->msd_switch)
+	if (!private->info->spdif_mode_control_name)
 		return 0;
 
-	err = scarlett2_update_input_level(mixer);
-	if (err < 0)
-		return err;
-
-	err = scarlett2_update_input_pad(mixer);
+	err = scarlett2_usb_get_config(mixer, SCARLETT2_CONFIG_SPDIF_MODE,
+				       1, &mode);
 	if (err < 0)
 		return err;
 
-	err = scarlett2_update_input_air(mixer);
-	if (err < 0)
-		return err;
+	private->spdif_mode = 0;
 
-	err = scarlett2_update_input_phantom(mixer);
-	if (err < 0)
-		return err;
-
-	err = scarlett2_update_direct_monitor(mixer);
-	if (err < 0)
-		return err;
-
-	/* the rest of the configuration is for devices with a mixer */
-	if (!scarlett2_has_mixer(private))
-		return 0;
-
-	err = scarlett2_update_monitor_mix(mixer);
-	if (err < 0)
-		return err;
-
-	err = scarlett2_update_monitor_other(mixer);
-	if (err < 0)
-		return err;
+	for (i = 0; *mode_values != 0xff; i++, mode_values++)
+		if (*mode_values == mode) {
+			private->spdif_mode = i;
+			break;
+		}
 
-	if (scarlett2_has_config_item(private,
-				      SCARLETT2_CONFIG_STANDALONE_SWITCH)) {
-		err = scarlett2_usb_get_config(
-			mixer, SCARLETT2_CONFIG_STANDALONE_SWITCH,
-			1, &private->standalone_switch);
-		if (err < 0)
-			return err;
-	}
+	return 0;
+}
 
-	if (scarlett2_has_config_item(private,
-				      SCARLETT2_CONFIG_POWER_EXT)) {
-		err = scarlett2_update_power_status(mixer);
-		if (err < 0)
-			return err;
-	}
+static int scarlett2_spdif_mode_ctl_info(struct snd_kcontrol *kctl,
+					   struct snd_ctl_elem_info *uinfo)
+{
+	struct usb_mixer_elem_info *elem = kctl->private_data;
+	struct scarlett2_data *private = elem->head.mixer->private_data;
+	const char * const *mode_texts = private->info->spdif_mode_texts;
+	int count = 0;
 
-	err = scarlett2_update_sync(mixer);
-	if (err < 0)
-		return err;
+	while (*mode_texts++)
+		count++;
 
-	if (scarlett2_has_config_item(private,
-				      SCARLETT2_CONFIG_LINE_OUT_VOLUME)) {
-		s16 sw_vol[SCARLETT2_ANALOGUE_MAX];
+	return snd_ctl_enum_info(uinfo, 1, count,
+				 private->info->spdif_mode_texts);
+}
 
-		/* read SW line out volume */
-		err = scarlett2_usb_get_config(
-			mixer, SCARLETT2_CONFIG_LINE_OUT_VOLUME,
-			private->num_line_out, &sw_vol);
-		if (err < 0)
-			return err;
+static int scarlett2_spdif_mode_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;
 
-		for (i = 0; i < private->num_line_out; i++)
-			private->vol[i] = clamp(
-				sw_vol[i] + SCARLETT2_VOLUME_BIAS,
-				0, SCARLETT2_VOLUME_BIAS);
+	ucontrol->value.enumerated.item[0] = private->spdif_mode;
+	return 0;
+}
 
-		/* read SW mute */
-		err = scarlett2_usb_get_config(
-			mixer, SCARLETT2_CONFIG_MUTE_SWITCH,
-			private->num_line_out, &private->mute_switch);
-		if (err < 0)
-			return err;
+static int scarlett2_spdif_mode_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 oval, val, err = 0;
+	int i;
 
-		for (i = 0; i < private->num_line_out; i++)
-			private->mute_switch[i] =
-				!!private->mute_switch[i];
+	mutex_lock(&private->data_mutex);
 
-		/* read SW/HW switches */
-		if (scarlett2_has_config_item(private,
-					      SCARLETT2_CONFIG_SW_HW_SWITCH)) {
-			err = scarlett2_usb_get_config(
-				mixer, SCARLETT2_CONFIG_SW_HW_SWITCH,
-				private->num_line_out,
-				&private->vol_sw_hw_switch);
-			if (err < 0)
-				return err;
+	oval = private->spdif_mode;
+	val = ucontrol->value.enumerated.item[0];
 
-			for (i = 0; i < private->num_line_out; i++)
-				private->vol_sw_hw_switch[i] =
-					!!private->vol_sw_hw_switch[i];
-		}
+	if (val < 0) {
+		err = -EINVAL;
+		goto unlock;
 	}
 
-	err = scarlett2_update_volumes(mixer);
-	if (err < 0)
-		return err;
+	for (i = 0; i <= val; i++)
+		if (private->info->spdif_mode_values[i] == 0xff) {
+			err = -EINVAL;
+			goto unlock;
+		}
 
-	err = scarlett2_update_dim_mute(mixer);
-	if (err < 0)
-		return err;
+	if (oval == val)
+		goto unlock;
 
-	err = scarlett2_update_input_select(mixer);
-	if (err < 0)
-		return err;
+	private->spdif_mode = val;
 
-	err = scarlett2_update_input_gain(mixer);
-	if (err < 0)
-		return err;
+	err = scarlett2_usb_set_config(
+		mixer, SCARLETT2_CONFIG_SPDIF_MODE, 0,
+		private->info->spdif_mode_values[val]);
+	if (!err)
+		err = 1;
 
-	err = scarlett2_update_autogain(mixer);
-	if (err < 0)
-		return err;
+unlock:
+	mutex_unlock(&private->data_mutex);
+	return err;
+}
 
-	err = scarlett2_update_input_safe(mixer);
-	if (err < 0)
-		return err;
+static const struct snd_kcontrol_new scarlett2_spdif_mode_ctl = {
+	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+	.name = "",
+	.info = scarlett2_spdif_mode_ctl_info,
+	.get  = scarlett2_spdif_mode_ctl_get,
+	.put  = scarlett2_spdif_mode_ctl_put,
+};
 
-	if (scarlett2_has_config_item(private,
-				      SCARLETT2_CONFIG_PCM_INPUT_SWITCH)) {
-		err = scarlett2_update_pcm_input_switch(mixer);
-		if (err < 0)
-			return err;
-	}
+static int scarlett2_add_spdif_mode_ctl(struct usb_mixer_interface *mixer)
+{
+	struct scarlett2_data *private = mixer->private_data;
 
-	err = scarlett2_update_mix(mixer);
-	if (err < 0)
-		return err;
+	if (!private->info->spdif_mode_control_name)
+		return 0;
 
-	return scarlett2_usb_get_mux(mixer);
+	return scarlett2_add_new_ctl(mixer, &scarlett2_spdif_mode_ctl,
+				     0, 1,
+				     private->info->spdif_mode_control_name,
+				     NULL);
 }
 
+/*** Notification Handlers ***/
+
 /* Notify on sync change */
 static void scarlett2_notify_sync(struct usb_mixer_interface *mixer)
 {
@@ -6902,6 +8170,36 @@ static void scarlett2_notify_input_air(struct usb_mixer_interface *mixer)
 			       &private->air_ctls[i]->id);
 }
 
+/* Notify on input DSP switch change */
+static void scarlett2_notify_input_dsp(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_dsp_updated = 1;
+
+	for (i = 0; i < info->dsp_input_count; i++)
+		snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
+			       &private->dsp_ctls[i]->id);
+}
+
+/* Notify on input mute switch change */
+static 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)
 {
@@ -6936,7 +8234,8 @@ static void scarlett2_notify_input_select(struct usb_mixer_interface *mixer)
 	const struct scarlett2_device_info *info = private->info;
 	int i;
 
-	if (!info->gain_input_count)
+	if (!scarlett2_has_config_item(private,
+				       SCARLETT2_CONFIG_INPUT_SELECT_SWITCH))
 		return;
 
 	private->input_select_updated = 1;
@@ -6988,6 +8287,12 @@ static void scarlett2_notify_autogain(struct usb_mixer_interface *mixer)
 			       &private->autogain_status_ctls[i]->id);
 	}
 
+	for (i = 0; i < SCARLETT2_AG_TARGET_COUNT; i++)
+		if (scarlett2_has_config_item(private,
+					      scarlett2_ag_target_configs[i]))
+			snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO,
+				       &private->ag_target_ctls[i]->id);
+
 	scarlett2_autogain_notify_access(mixer);
 }
 
@@ -6999,12 +8304,12 @@ static void scarlett2_notify_input_safe(struct usb_mixer_interface *mixer)
 	const struct scarlett2_device_info *info = private->info;
 	int i;
 
-	if (!info->gain_input_count)
+	if (!info->safe_input_count)
 		return;
 
 	private->input_safe_updated = 1;
 
-	for (i = 0; i < info->gain_input_count; i++)
+	for (i = 0; i < info->safe_input_count; i++)
 		snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
 			       &private->safe_ctls[i]->id);
 }
@@ -7107,6 +8412,33 @@ static void scarlett2_notify_pcm_input_switch(struct usb_mixer_interface *mixer)
 	scarlett2_notify_mux(mixer);
 }
 
+/* Notify on Bluetooth change */
+static void scarlett2_notify_bluetooth(struct usb_mixer_interface *mixer)
+{
+	struct snd_card *card = mixer->chip->card;
+	struct scarlett2_data *private = mixer->private_data;
+
+	if (!private->info->has_bluetooth)
+		return;
+
+	private->bluetooth_updated = 1;
+
+	snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
+		       &private->bluetooth_volume_ctl->id);
+}
+
+/* Handle acknowledgement that a command was received; let
+ * scarlett2_usb() know that it can proceed
+ */
+static void scarlett2_notify_ack(struct usb_mixer_interface *mixer)
+{
+	struct scarlett2_data *private = mixer->private_data;
+
+	/* if running == 0, ignore ACKs */
+	if (private->running)
+		complete(&private->cmd_done);
+}
+
 /* Interrupt callback */
 static void scarlett2_notify(struct urb *urb)
 {
@@ -7123,6 +8455,12 @@ static void scarlett2_notify(struct urb *urb)
 
 	data = le32_to_cpu(*(__le32 *)urb->transfer_buffer);
 
+	/* Ignore notifications except ACK during initialisation.
+	 * ACK is 0x00000001 on every device.
+	 */
+	if (private->running < 2)
+		data &= 1;
+
 	while (data && notifications->mask) {
 		if (data & notifications->mask) {
 			data &= ~notifications->mask;
@@ -7143,9 +8481,141 @@ requeue:
 	    ustatus != -ESHUTDOWN) {
 		urb->dev = mixer->chip->dev;
 		usb_submit_urb(urb, GFP_ATOMIC);
+	} else {
+		complete(&private->cmd_done);
 	}
 }
 
+/*** Cleanup/Suspend Callbacks ***/
+
+static void scarlett2_private_free(struct usb_mixer_interface *mixer)
+{
+	struct scarlett2_data *private = mixer->private_data;
+
+	cancel_delayed_work_sync(&private->work);
+	kfree(private);
+	mixer->private_data = NULL;
+}
+
+static void scarlett2_private_suspend(struct usb_mixer_interface *mixer)
+{
+	struct scarlett2_data *private = mixer->private_data;
+
+	if (cancel_delayed_work_sync(&private->work))
+		scarlett2_config_save(private->mixer);
+}
+
+/*** Initialisation ***/
+
+static void scarlett2_count_io(struct scarlett2_data *private)
+{
+	const struct scarlett2_device_info *info = private->info;
+	const struct scarlett2_config_set *config_set = info->config_set;
+	const int (*port_count)[SCARLETT2_PORT_DIRNS] = info->port_count;
+	int port_type, srcs = 0, dsts = 0, i;
+
+	/* Count the number of mux sources and destinations */
+	for (port_type = 0;
+	     port_type < SCARLETT2_PORT_TYPE_COUNT;
+	     port_type++) {
+		srcs += port_count[port_type][SCARLETT2_PORT_IN];
+		dsts += port_count[port_type][SCARLETT2_PORT_OUT];
+	}
+
+	private->num_mux_srcs = srcs;
+	private->num_mux_dsts = dsts;
+
+	/* Mixer inputs are mux outputs and vice versa.
+	 * Scarlett Gen 4 DSP I/O uses SCARLETT2_PORT_TYPE_MIX but
+	 * doesn't have mixer controls.
+	 */
+	private->num_mix_in =
+		port_count[SCARLETT2_PORT_TYPE_MIX][SCARLETT2_PORT_OUT] -
+			info->dsp_count;
+
+	private->num_mix_out =
+		port_count[SCARLETT2_PORT_TYPE_MIX][SCARLETT2_PORT_IN] -
+			info->dsp_count;
+
+	/* Number of analogue line outputs */
+	private->num_line_out =
+		port_count[SCARLETT2_PORT_TYPE_ANALOGUE][SCARLETT2_PORT_OUT];
+
+	/* Number of monitor mix controls */
+	private->num_monitor_mix_ctls =
+		info->direct_monitor * 2 * private->num_mix_in;
+
+	/* Number of autogain status texts */
+	if (config_set->autogain_status_texts) {
+		const char * const *texts = config_set->autogain_status_texts;
+
+		for (i = 0; texts[i]; i++)
+			;
+		private->num_autogain_status_texts = i;
+	}
+}
+
+/* Look through the interface descriptors for the Focusrite Control
+ * interface (bInterfaceClass = 255 Vendor Specific Class) and set
+ * bInterfaceNumber, bEndpointAddress, wMaxPacketSize, and bInterval
+ * in private
+ */
+static int scarlett2_find_fc_interface(struct usb_device *dev,
+				       struct scarlett2_data *private)
+{
+	struct usb_host_config *config = dev->actconfig;
+	int i;
+
+	for (i = 0; i < config->desc.bNumInterfaces; i++) {
+		struct usb_interface *intf = config->interface[i];
+		struct usb_interface_descriptor *desc =
+			&intf->altsetting[0].desc;
+		struct usb_endpoint_descriptor *epd;
+
+		if (desc->bInterfaceClass != 255)
+			continue;
+
+		epd = get_endpoint(intf->altsetting, 0);
+		private->bInterfaceNumber = desc->bInterfaceNumber;
+		private->bEndpointAddress = epd->bEndpointAddress &
+			USB_ENDPOINT_NUMBER_MASK;
+		private->wMaxPacketSize = le16_to_cpu(epd->wMaxPacketSize);
+		private->bInterval = epd->bInterval;
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+/* Initialise private data */
+static int scarlett2_init_private(struct usb_mixer_interface *mixer,
+				  const struct scarlett2_device_entry *entry)
+{
+	struct scarlett2_data *private =
+		kzalloc(sizeof(struct scarlett2_data), GFP_KERNEL);
+
+	if (!private)
+		return -ENOMEM;
+
+	mutex_init(&private->usb_mutex);
+	mutex_init(&private->data_mutex);
+	INIT_DELAYED_WORK(&private->work, scarlett2_config_save_work);
+
+	mixer->private_data = private;
+	mixer->private_free = scarlett2_private_free;
+	mixer->private_suspend = scarlett2_private_suspend;
+
+	private->info = entry->info;
+	private->config_set = entry->info->config_set;
+	private->series_name = entry->series_name;
+	scarlett2_count_io(private);
+	private->scarlett2_seq = 0;
+	private->mixer = mixer;
+
+	return scarlett2_find_fc_interface(mixer->chip->dev, private);
+}
+
+/* Submit a URB to receive notifications from the device */
 static int scarlett2_init_notify(struct usb_mixer_interface *mixer)
 {
 	struct usb_device *dev = mixer->chip->dev;
@@ -7174,9 +8644,341 @@ static int scarlett2_init_notify(struct usb_mixer_interface *mixer)
 			 transfer_buffer, private->wMaxPacketSize,
 			 scarlett2_notify, mixer, private->bInterval);
 
+	init_completion(&private->cmd_done);
+
 	return usb_submit_urb(mixer->urb, GFP_KERNEL);
 }
 
+/* Cargo cult proprietary initialisation sequence */
+static int scarlett2_usb_init(struct usb_mixer_interface *mixer)
+{
+	struct usb_device *dev = mixer->chip->dev;
+	struct scarlett2_data *private = mixer->private_data;
+	u8 step0_buf[24];
+	u8 step2_buf[84];
+	int err;
+
+	if (usb_pipe_type_check(dev, usb_sndctrlpipe(dev, 0)))
+		return -EINVAL;
+
+	/* step 0 */
+	err = scarlett2_usb_rx(dev, private->bInterfaceNumber,
+			       SCARLETT2_USB_CMD_INIT,
+			       step0_buf, sizeof(step0_buf));
+	if (err < 0)
+		return err;
+
+	/* Set up the interrupt polling for notifications.
+	 * When running is:
+	 * 0: all notifications are ignored
+	 * 1: only ACKs are handled
+	 * 2: all notifications are handled
+	 */
+	err = scarlett2_init_notify(mixer);
+	if (err < 0)
+		return err;
+
+	/* sleep for a moment in case of an outstanding ACK */
+	msleep(20);
+
+	/* start handling ACKs, but no other notifications until the
+	 * ALSA controls have been created
+	 */
+	private->running = 1;
+
+	/* step 1 */
+	private->scarlett2_seq = 1;
+	err = scarlett2_usb(mixer, SCARLETT2_USB_INIT_1, NULL, 0, NULL, 0);
+	if (err < 0)
+		return err;
+
+	/* step 2 */
+	private->scarlett2_seq = 1;
+	err = scarlett2_usb(mixer, SCARLETT2_USB_INIT_2,
+			    NULL, 0,
+			    step2_buf, sizeof(step2_buf));
+	if (err < 0)
+		return err;
+
+	/* extract 4-byte firmware version from step2_buf[8] */
+	private->firmware_version = le32_to_cpu(*(__le32 *)(step2_buf + 8));
+	usb_audio_info(mixer->chip,
+		       "Firmware version %d\n",
+		       private->firmware_version);
+
+	return 0;
+}
+
+/* Get the flash segment numbers for the App_Settings and App_Upgrade
+ * segments and put them in the private data
+ */
+static int scarlett2_get_flash_segment_nums(struct usb_mixer_interface *mixer)
+{
+	struct scarlett2_data *private = mixer->private_data;
+	int err, count, i;
+
+	struct {
+		__le32 size;
+		__le32 count;
+		u8 unknown[8];
+	} __packed flash_info;
+
+	struct {
+		__le32 size;
+		__le32 flags;
+		char name[16];
+	} __packed segment_info;
+
+	err = scarlett2_usb(mixer, SCARLETT2_USB_INFO_FLASH,
+			    NULL, 0,
+			    &flash_info, sizeof(flash_info));
+	if (err < 0)
+		return err;
+
+	count = le32_to_cpu(flash_info.count);
+
+	/* sanity check count */
+	if (count < SCARLETT2_SEGMENT_NUM_MIN ||
+	    count > SCARLETT2_SEGMENT_NUM_MAX + 1) {
+		usb_audio_err(mixer->chip,
+			      "invalid flash segment count: %d\n", count);
+		return -EINVAL;
+	}
+
+	for (i = 0; i < count; i++) {
+		__le32 segment_num_req = cpu_to_le32(i);
+		int flash_segment_id;
+
+		err = scarlett2_usb(mixer, SCARLETT2_USB_INFO_SEGMENT,
+				    &segment_num_req, sizeof(segment_num_req),
+				    &segment_info, sizeof(segment_info));
+		if (err < 0) {
+			usb_audio_err(mixer->chip,
+				"failed to get flash segment info %d: %d\n",
+				i, err);
+			return err;
+		}
+
+		if (!strncmp(segment_info.name,
+			     SCARLETT2_SEGMENT_SETTINGS_NAME, 16))
+			flash_segment_id = SCARLETT2_SEGMENT_ID_SETTINGS;
+		else if (!strncmp(segment_info.name,
+				  SCARLETT2_SEGMENT_FIRMWARE_NAME, 16))
+			flash_segment_id = SCARLETT2_SEGMENT_ID_FIRMWARE;
+		else
+			continue;
+
+		private->flash_segment_nums[flash_segment_id] = i;
+		private->flash_segment_blocks[flash_segment_id] =
+			le32_to_cpu(segment_info.size) /
+				SCARLETT2_FLASH_BLOCK_SIZE;
+	}
+
+	/* segment 0 is App_Gold and we never want to touch that, so
+	 * use 0 as the "not-found" value
+	 */
+	if (!private->flash_segment_nums[SCARLETT2_SEGMENT_ID_SETTINGS]) {
+		usb_audio_err(mixer->chip,
+			      "failed to find flash segment %s\n",
+			      SCARLETT2_SEGMENT_SETTINGS_NAME);
+		return -EINVAL;
+	}
+	if (!private->flash_segment_nums[SCARLETT2_SEGMENT_ID_FIRMWARE]) {
+		usb_audio_err(mixer->chip,
+			      "failed to find flash segment %s\n",
+			      SCARLETT2_SEGMENT_FIRMWARE_NAME);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/* Read configuration from the interface on start */
+static int scarlett2_read_configs(struct usb_mixer_interface *mixer)
+{
+	struct scarlett2_data *private = mixer->private_data;
+	const struct scarlett2_device_info *info = private->info;
+	int err, i;
+
+	if (scarlett2_has_config_item(private, SCARLETT2_CONFIG_MSD_SWITCH)) {
+		err = scarlett2_usb_get_config(
+			mixer, SCARLETT2_CONFIG_MSD_SWITCH,
+			1, &private->msd_switch);
+		if (err < 0)
+			return err;
+	}
+
+	if (private->firmware_version < info->min_firmware_version) {
+		usb_audio_err(mixer->chip,
+			      "Focusrite %s firmware version %d is too old; "
+			      "need %d",
+			      private->series_name,
+			      private->firmware_version,
+			      info->min_firmware_version);
+		return 0;
+	}
+
+	/* no other controls are created if MSD mode is on */
+	if (private->msd_switch)
+		return 0;
+
+	err = scarlett2_update_input_level(mixer);
+	if (err < 0)
+		return err;
+
+	err = scarlett2_update_input_pad(mixer);
+	if (err < 0)
+		return err;
+
+	err = scarlett2_update_input_air(mixer);
+	if (err < 0)
+		return err;
+
+	err = scarlett2_update_input_dsp(mixer);
+	if (err < 0)
+		return err;
+
+	err = scarlett2_update_compressor_values(mixer);
+	if (err < 0)
+		return err;
+
+	err = scarlett2_update_filter_values(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;
+
+	err = scarlett2_update_direct_monitor(mixer);
+	if (err < 0)
+		return err;
+
+	/* the rest of the configuration is for devices with a mixer */
+	if (!scarlett2_has_mixer(private))
+		return 0;
+
+	err = scarlett2_update_monitor_mix(mixer);
+	if (err < 0)
+		return err;
+
+	err = scarlett2_update_monitor_other(mixer);
+	if (err < 0)
+		return err;
+
+	if (scarlett2_has_config_item(private,
+				      SCARLETT2_CONFIG_STANDALONE_SWITCH)) {
+		err = scarlett2_usb_get_config(
+			mixer, SCARLETT2_CONFIG_STANDALONE_SWITCH,
+			1, &private->standalone_switch);
+		if (err < 0)
+			return err;
+	}
+
+	if (scarlett2_has_config_item(private,
+				      SCARLETT2_CONFIG_POWER_EXT)) {
+		err = scarlett2_update_power_status(mixer);
+		if (err < 0)
+			return err;
+	}
+
+	err = scarlett2_update_sync(mixer);
+	if (err < 0)
+		return err;
+
+	if (scarlett2_has_config_item(private,
+				      SCARLETT2_CONFIG_LINE_OUT_VOLUME)) {
+		s16 sw_vol[SCARLETT2_ANALOGUE_MAX];
+
+		/* read SW line out volume */
+		err = scarlett2_usb_get_config(
+			mixer, SCARLETT2_CONFIG_LINE_OUT_VOLUME,
+			private->num_line_out, &sw_vol);
+		if (err < 0)
+			return err;
+
+		for (i = 0; i < private->num_line_out; i++)
+			private->vol[i] = clamp(
+				sw_vol[i] + SCARLETT2_VOLUME_BIAS,
+				0, SCARLETT2_VOLUME_BIAS);
+
+		/* read SW mute */
+		err = scarlett2_usb_get_config(
+			mixer, SCARLETT2_CONFIG_MUTE_SWITCH,
+			private->num_line_out, &private->mute_switch);
+		if (err < 0)
+			return err;
+
+		for (i = 0; i < private->num_line_out; i++)
+			private->mute_switch[i] =
+				!!private->mute_switch[i];
+
+		/* read SW/HW switches */
+		if (scarlett2_has_config_item(private,
+					      SCARLETT2_CONFIG_SW_HW_SWITCH)) {
+			err = scarlett2_usb_get_config(
+				mixer, SCARLETT2_CONFIG_SW_HW_SWITCH,
+				private->num_line_out,
+				&private->vol_sw_hw_switch);
+			if (err < 0)
+				return err;
+
+			for (i = 0; i < private->num_line_out; i++)
+				private->vol_sw_hw_switch[i] =
+					!!private->vol_sw_hw_switch[i];
+		}
+	}
+
+	err = scarlett2_update_volumes(mixer);
+	if (err < 0)
+		return err;
+
+	err = scarlett2_update_dim_mute(mixer);
+	if (err < 0)
+		return err;
+
+	err = scarlett2_update_input_select(mixer);
+	if (err < 0)
+		return err;
+
+	err = scarlett2_update_input_gain(mixer);
+	if (err < 0)
+		return err;
+
+	err = scarlett2_update_autogain(mixer);
+	if (err < 0)
+		return err;
+
+	err = scarlett2_update_input_safe(mixer);
+	if (err < 0)
+		return err;
+
+	if (scarlett2_has_config_item(private,
+				      SCARLETT2_CONFIG_PCM_INPUT_SWITCH)) {
+		err = scarlett2_update_pcm_input_switch(mixer);
+		if (err < 0)
+			return err;
+	}
+
+	err = scarlett2_update_bluetooth_volume(mixer);
+	if (err < 0)
+		return err;
+
+	err = scarlett2_update_spdif_mode(mixer);
+	if (err < 0)
+		return err;
+
+	err = scarlett2_update_mix(mixer);
+	if (err < 0)
+		return err;
+
+	return scarlett2_usb_get_mux(mixer);
+}
+
 static const struct scarlett2_device_entry *get_scarlett2_device_entry(
 	struct usb_mixer_interface *mixer)
 {
@@ -7297,6 +9099,16 @@ static int snd_scarlett2_controls_create(
 	if (err < 0)
 		return err;
 
+	/* Create the Bluetooth volume control */
+	err = scarlett2_add_bluetooth_volume_ctl(mixer);
+	if (err < 0)
+		return err;
+
+	/* Create the S/PDIF mode control */
+	err = scarlett2_add_spdif_mode_ctl(mixer);
+	if (err < 0)
+		return err;
+
 	/* Set the access mode of controls disabled during
 	 * autogain/phantom power switching.
 	 */
@@ -7305,10 +9117,8 @@ static int snd_scarlett2_controls_create(
 		scarlett2_phantom_update_access(mixer);
 	}
 
-	/* Set up the interrupt polling */
-	err = scarlett2_init_notify(mixer);
-	if (err < 0)
-		return err;
+	/* Start handling all notifications */
+	private->running = 2;
 
 	return 0;
 }
@@ -7397,7 +9207,7 @@ static int scarlett2_reboot(struct usb_mixer_interface *mixer)
 	return scarlett2_usb(mixer, SCARLETT2_USB_REBOOT, NULL, 0, NULL, 0);
 }
 
-/* Select a flash segment for erasing (and possibly writing to) */
+/* Select a flash segment for reading/erasing/writing */
 static int scarlett2_ioctl_select_flash_segment(
 	struct usb_mixer_interface *mixer,
 	unsigned long arg)
@@ -7578,6 +9388,84 @@ static int scarlett2_hwdep_ioctl(struct snd_hwdep *hw, struct file *file,
 	}
 }
 
+static long scarlett2_hwdep_read(struct snd_hwdep *hw,
+				 char __user *buf,
+				 long count, loff_t *offset)
+{
+	struct usb_mixer_interface *mixer = hw->private_data;
+	struct scarlett2_data *private = mixer->private_data;
+	int segment_id, segment_num, err;
+	int flash_size;
+
+	/* SCARLETT2_USB_READ_SEGMENT request data */
+	struct {
+		__le32 segment_num;
+		__le32 offset;
+		__le32 len;
+	} __packed req;
+
+	u8 *resp;
+
+	/* Flash segment must first be selected */
+	if (private->flash_write_state != SCARLETT2_FLASH_WRITE_STATE_SELECTED)
+		return -EINVAL;
+
+	/* Get the selected flash segment number */
+	segment_id = private->selected_flash_segment_id;
+	if (segment_id < 0 || segment_id >= SCARLETT2_SEGMENT_ID_COUNT)
+		return -EINVAL;
+
+	segment_num = private->flash_segment_nums[segment_id];
+	if (segment_num < 0 ||
+	    segment_num > SCARLETT2_SEGMENT_NUM_MAX)
+		return -EFAULT;
+
+	/* Validate the offset and count */
+	if (count < 0 || *offset < 0)
+		return -EINVAL;
+
+	/* Reached EOF? */
+	flash_size = private->flash_segment_blocks[segment_id] *
+		     SCARLETT2_FLASH_BLOCK_SIZE;
+	if (!count || *offset >= flash_size)
+		return 0;
+
+	/* Limit the numbers of bytes read to SCARLETT2_FLASH_RW_MAX */
+	if (count > SCARLETT2_FLASH_RW_MAX)
+		count = SCARLETT2_FLASH_RW_MAX;
+
+	/* Limit read to EOF */
+	if (*offset + count >= flash_size)
+		count = flash_size - *offset;
+
+	/* Create and send the request */
+	req.segment_num = cpu_to_le32(segment_num);
+	req.offset = cpu_to_le32(*offset);
+	req.len = cpu_to_le32(count);
+
+	resp = kzalloc(count, GFP_KERNEL);
+	if (!resp)
+		return -ENOMEM;
+
+	err = scarlett2_usb(mixer, SCARLETT2_USB_READ_SEGMENT,
+			    &req, sizeof(req), resp, count);
+	if (err < 0)
+		goto error;
+
+	/* Copy the response to userspace */
+	if (copy_to_user(buf, resp, count)) {
+		err = -EFAULT;
+		goto error;
+	}
+
+	*offset += count;
+	err = count;
+
+error:
+	kfree(resp);
+	return err;
+}
+
 static long scarlett2_hwdep_write(struct snd_hwdep *hw,
 				  const char __user *buf,
 				  long count, loff_t *offset)
@@ -7596,7 +9484,7 @@ static long scarlett2_hwdep_write(struct snd_hwdep *hw,
 	} __packed *req;
 
 	/* Calculate the maximum permitted in data[] */
-	const size_t max_data_size = SCARLETT2_FLASH_WRITE_MAX -
+	const size_t max_data_size = SCARLETT2_FLASH_RW_MAX -
 				     offsetof(typeof(*req), data);
 
 	/* If erasing, wait for it to complete */
@@ -7633,7 +9521,7 @@ static long scarlett2_hwdep_write(struct snd_hwdep *hw,
 	if (!count)
 		return 0;
 
-	/* Limit the *req size to SCARLETT2_FLASH_WRITE_MAX */
+	/* Limit the *req size to SCARLETT2_FLASH_RW_MAX */
 	if (count > max_data_size)
 		count = max_data_size;
 
@@ -7694,6 +9582,7 @@ static int scarlett2_hwdep_init(struct usb_mixer_interface *mixer)
 	hw->exclusive = 1;
 	hw->ops.open = scarlett2_hwdep_open;
 	hw->ops.ioctl = scarlett2_hwdep_ioctl;
+	hw->ops.read = scarlett2_hwdep_read;
 	hw->ops.write = scarlett2_hwdep_write;
 	hw->ops.release = scarlett2_hwdep_release;