diff --git a/include/uapi/sound/firewire.h b/include/uapi/sound/firewire.h
index a8df8fb03b52..bb5ecff73896 100644
--- a/include/uapi/sound/firewire.h
+++ b/include/uapi/sound/firewire.h
@@ -145,6 +145,34 @@ struct snd_firewire_motu_register_dsp_meter {
 	__u8 data[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_METER_COUNT];
 };
 
+#define SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_COUNT		4
+#define SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_SRC_COUNT	20
+
+/**
+ * snd_firewire_motu_register_dsp_parameter - the container for parameters of DSP controlled
+ *					      by register access.
+ * @mixer.source.gain: The gain of source to mixer.
+ * @mixer.source.pan: The L/R balance of source to mixer.
+ * @mixer.source.flag: The flag of source to mixer, including mute, solo.
+ * @mixer.source.paired_balance: The L/R balance of paired source to mixer, only for 4 pre and
+ *				 Audio Express.
+ * @mixer.source.paired_width: The width of paired source to mixer, only for 4 pre and
+ *			       Audio Express.
+ *
+ * The structure expresses the set of parameters for DSP controlled by register access.
+ */
+struct snd_firewire_motu_register_dsp_parameter {
+	struct {
+		struct {
+			__u8 gain[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_SRC_COUNT];
+			__u8 pan[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_SRC_COUNT];
+			__u8 flag[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_SRC_COUNT];
+			__u8 paired_balance[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_SRC_COUNT];
+			__u8 paired_width[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_SRC_COUNT];
+		} source[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_COUNT];
+	} mixer;
+};
+
 // In below MOTU models, software is allowed to control their DSP by command in frame of
 // asynchronous transaction to 0x'ffff'0001'0000:
 //
diff --git a/sound/firewire/motu/motu-register-dsp-message-parser.c b/sound/firewire/motu/motu-register-dsp-message-parser.c
index fe804615294c..6df40e5ee9db 100644
--- a/sound/firewire/motu/motu-register-dsp-message-parser.c
+++ b/sound/firewire/motu/motu-register-dsp-message-parser.c
@@ -82,6 +82,11 @@ struct msg_parser {
 	spinlock_t lock;
 	struct snd_firewire_motu_register_dsp_meter meter;
 	bool meter_pos_quirk;
+
+	struct snd_firewire_motu_register_dsp_parameter param;
+	u8 prev_mixer_src_type;
+	u8 mixer_ch;
+	u8 mixer_src_ch;
 };
 
 int snd_motu_register_dsp_message_parser_new(struct snd_motu *motu)
@@ -99,6 +104,12 @@ int snd_motu_register_dsp_message_parser_new(struct snd_motu *motu)
 
 int snd_motu_register_dsp_message_parser_init(struct snd_motu *motu)
 {
+	struct msg_parser *parser = motu->message_parser;
+
+	parser->prev_mixer_src_type = INVALID;
+	parser->mixer_ch = 0xff;
+	parser->mixer_src_ch = 0xff;
+
 	return 0;
 }
 
@@ -126,6 +137,59 @@ void snd_motu_register_dsp_message_parser_parse(struct snd_motu *motu, const str
 			buffer += data_block_quadlets;
 
 			switch (msg_type) {
+			case MIXER_SELECT:
+			{
+				u8 mixer_ch = val / 0x20;
+				if (mixer_ch < SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_COUNT) {
+					parser->mixer_src_ch = 0;
+					parser->mixer_ch = mixer_ch;
+				}
+				break;
+			}
+			case MIXER_SRC_GAIN:
+			case MIXER_SRC_PAN:
+			case MIXER_SRC_FLAG:
+			case MIXER_SRC_PAIRED_BALANCE:
+			case MIXER_SRC_PAIRED_WIDTH:
+			{
+				struct snd_firewire_motu_register_dsp_parameter *param = &parser->param;
+				u8 mixer_ch = parser->mixer_ch;
+				u8 mixer_src_ch = parser->mixer_src_ch;
+
+				if (msg_type != parser->prev_mixer_src_type)
+					mixer_src_ch = 0;
+				else
+					++mixer_src_ch;
+				parser->prev_mixer_src_type = msg_type;
+
+				if (mixer_ch < SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_COUNT &&
+				    mixer_src_ch < SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_SRC_COUNT) {
+					u8 mixer_ch = parser->mixer_ch;
+
+					switch (msg_type) {
+					case MIXER_SRC_GAIN:
+						param->mixer.source[mixer_ch].gain[mixer_src_ch] = val;
+						break;
+					case MIXER_SRC_PAN:
+						param->mixer.source[mixer_ch].pan[mixer_src_ch] = val;
+						break;
+					case MIXER_SRC_FLAG:
+						param->mixer.source[mixer_ch].flag[mixer_src_ch] = val;
+						break;
+					case MIXER_SRC_PAIRED_BALANCE:
+						param->mixer.source[mixer_ch].paired_balance[mixer_src_ch] = val;
+						break;
+					case MIXER_SRC_PAIRED_WIDTH:
+						param->mixer.source[mixer_ch].paired_width[mixer_src_ch] = val;
+						break;
+					default:
+						break;
+					}
+
+					parser->mixer_src_ch = mixer_src_ch;
+				}
+				break;
+			}
 			case METER:
 			{
 				u8 pos;