diff --git a/sound/firewire/oxfw/Makefile b/sound/firewire/oxfw/Makefile
index 53b5572..4ee2c97 100644
--- a/sound/firewire/oxfw/Makefile
+++ b/sound/firewire/oxfw/Makefile
@@ -1,2 +1,3 @@
-snd-oxfw-objs := oxfw_stream.o oxfw_control.o oxfw_proc.o oxfw_pcm.o oxfw.o
+snd-oxfw-objs := oxfw_command.o oxfw_stream.o oxfw_control.o oxfw_proc.o \
+		 oxfw_pcm.o oxfw.o
 obj-m += snd-oxfw.o
diff --git a/sound/firewire/oxfw/oxfw.c b/sound/firewire/oxfw/oxfw.c
index d900718..825377a 100644
--- a/sound/firewire/oxfw/oxfw.c
+++ b/sound/firewire/oxfw/oxfw.c
@@ -97,10 +97,7 @@ static int oxfw_probe(struct fw_unit *unit,
 	oxfw->unit = unit;
 	oxfw->device_info = (const struct device_info *)id->driver_data;
 
-	if (oxfw->device_info == &griffin_firewave)
-		err = firewave_stream_discover(oxfw);
-	else
-		err = lacie_speakers_stream_discover(oxfw);
+	err = snd_oxfw_stream_discover(oxfw);
 	if (err < 0)
 		goto error;
 
diff --git a/sound/firewire/oxfw/oxfw.h b/sound/firewire/oxfw/oxfw.h
index e845581..b21dfce 100644
--- a/sound/firewire/oxfw/oxfw.h
+++ b/sound/firewire/oxfw/oxfw.h
@@ -59,15 +59,45 @@ struct snd_oxfw {
 	s16 volume_max;
 };
 
+/*
+ * AV/C Stream Format Information Specification 1.1 Working Draft
+ * (Apr 2005, 1394TA)
+ */
+int avc_stream_get_format(struct fw_unit *unit,
+			  enum avc_general_plug_dir dir, unsigned int pid,
+			  u8 *buf, unsigned int *len, unsigned int eid);
+static inline int
+avc_stream_get_format_single(struct fw_unit *unit,
+			     enum avc_general_plug_dir dir, unsigned int pid,
+			     u8 *buf, unsigned int *len)
+{
+	return avc_stream_get_format(unit, dir, pid, buf, len, 0xff);
+}
+static inline int
+avc_stream_get_format_list(struct fw_unit *unit,
+			   enum avc_general_plug_dir dir, unsigned int pid,
+			   u8 *buf, unsigned int *len,
+			   unsigned int eid)
+{
+	return avc_stream_get_format(unit, dir, pid, buf, len, eid);
+}
+
+/*
+ * AV/C Digital Interface Command Set General Specification 4.2
+ * (Sep 2004, 1394TA)
+ */
+int avc_general_inquiry_sig_fmt(struct fw_unit *unit, unsigned int rate,
+				enum avc_general_plug_dir dir,
+				unsigned short pid);
+
 int snd_oxfw_stream_init_simplex(struct snd_oxfw *oxfw);
 int snd_oxfw_stream_start_simplex(struct snd_oxfw *oxfw, unsigned int rate,
 				  unsigned int pcm_channels);
 void snd_oxfw_stream_stop_simplex(struct snd_oxfw *oxfw);
 void snd_oxfw_stream_destroy_simplex(struct snd_oxfw *oxfw);
 void snd_oxfw_stream_update_simplex(struct snd_oxfw *oxfw);
+int snd_oxfw_stream_discover(struct snd_oxfw *oxfw);
 
-int firewave_stream_discover(struct snd_oxfw *oxfw);
-int lacie_speakers_stream_discover(struct snd_oxfw *oxfw);
 int snd_oxfw_create_pcm(struct snd_oxfw *oxfw);
 
 int snd_oxfw_create_mixer(struct snd_oxfw *oxfw);
diff --git a/sound/firewire/oxfw/oxfw_command.c b/sound/firewire/oxfw/oxfw_command.c
new file mode 100644
index 0000000..e3599d1
--- /dev/null
+++ b/sound/firewire/oxfw/oxfw_command.c
@@ -0,0 +1,113 @@
+/*
+ * oxfw_command.c - a part of driver for OXFW970/971 based devices
+ *
+ * Copyright (c) 2014 Takashi Sakamoto
+ *
+ * Licensed under the terms of the GNU General Public License, version 2.
+ */
+
+#include "oxfw.h"
+
+int avc_stream_get_format(struct fw_unit *unit,
+			  enum avc_general_plug_dir dir, unsigned int pid,
+			  u8 *buf, unsigned int *len, unsigned int eid)
+{
+	unsigned int subfunc;
+	int err;
+
+	if (eid == 0xff)
+		subfunc = 0xc0;	/* SINGLE */
+	else
+		subfunc = 0xc1;	/* LIST */
+
+	buf[0] = 0x01;		/* STATUS */
+	buf[1] = 0xff;		/* UNIT */
+	buf[2] = 0xbf;		/* EXTENDED STREAM FORMAT INFORMATION */
+	buf[3] = subfunc;	/* SINGLE or LIST */
+	buf[4] = dir;		/* Plug Direction */
+	buf[5] = 0x00;		/* Unit */
+	buf[6] = 0x00;		/* PCR (Isochronous Plug) */
+	buf[7] = 0xff & pid;	/* Plug ID */
+	buf[8] = 0xff;		/* Padding */
+	buf[9] = 0xff;		/* support status in response */
+	buf[10] = 0xff & eid;	/* entry ID for LIST subfunction */
+	buf[11] = 0xff;		/* padding */
+
+	/* do transaction and check buf[1-7] are the same against command */
+	err = fcp_avc_transaction(unit, buf, 12, buf, *len,
+				  BIT(1) | BIT(2) | BIT(3) | BIT(4) | BIT(5) |
+				  BIT(6) | BIT(7));
+	if ((err > 0) && (err < 10))
+		err = -EIO;
+	else if (buf[0] == 0x08)	/* NOT IMPLEMENTED */
+		err = -ENOSYS;
+	else if (buf[0] == 0x0a)	/* REJECTED */
+		err = -EINVAL;
+	else if (buf[0] == 0x0b)	/* IN TRANSITION */
+		err = -EAGAIN;
+	/* LIST subfunction has entry ID */
+	else if ((subfunc == 0xc1) && (buf[10] != eid))
+		err = -EIO;
+	if (err < 0)
+		goto end;
+
+	/* keep just stream format information */
+	if (subfunc == 0xc0) {
+		memmove(buf, buf + 10, err - 10);
+		*len = err - 10;
+	} else {
+		memmove(buf, buf + 11, err - 11);
+		*len = err - 11;
+	}
+
+	err = 0;
+end:
+	return err;
+}
+
+int avc_general_inquiry_sig_fmt(struct fw_unit *unit, unsigned int rate,
+				enum avc_general_plug_dir dir,
+				unsigned short pid)
+{
+	unsigned int sfc;
+	u8 *buf;
+	int err;
+
+	for (sfc = 0; sfc < CIP_SFC_COUNT; sfc++) {
+		if (amdtp_rate_table[sfc] == rate)
+			break;
+	}
+	if (sfc == CIP_SFC_COUNT)
+		return -EINVAL;
+
+	buf = kzalloc(8, GFP_KERNEL);
+	if (buf == NULL)
+		return -ENOMEM;
+
+	buf[0] = 0x02;		/* SPECIFIC INQUIRY */
+	buf[1] = 0xff;		/* UNIT */
+	if (dir == AVC_GENERAL_PLUG_DIR_IN)
+		buf[2] = 0x19;	/* INPUT PLUG SIGNAL FORMAT */
+	else
+		buf[2] = 0x18;	/* OUTPUT PLUG SIGNAL FORMAT */
+	buf[3] = 0xff & pid;	/* plug id */
+	buf[4] = 0x90;		/* EOH_1, Form_1, FMT. AM824 */
+	buf[5] = 0x07 & sfc;	/* FDF-hi. AM824, frequency */
+	buf[6] = 0xff;		/* FDF-mid. AM824, SYT hi (not used) */
+	buf[7] = 0xff;		/* FDF-low. AM824, SYT lo (not used) */
+
+	/* do transaction and check buf[1-5] are the same against command */
+	err = fcp_avc_transaction(unit, buf, 8, buf, 8,
+				  BIT(1) | BIT(2) | BIT(3) | BIT(4) | BIT(5));
+	if ((err > 0) && (err < 8))
+		err = -EIO;
+	else if (buf[0] == 0x08)	/* NOT IMPLEMENTED */
+		err = -ENOSYS;
+	if (err < 0)
+		goto end;
+
+	err = 0;
+end:
+	kfree(buf);
+	return err;
+}
diff --git a/sound/firewire/oxfw/oxfw_stream.c b/sound/firewire/oxfw/oxfw_stream.c
index 2d09df8..0d81bba 100644
--- a/sound/firewire/oxfw/oxfw_stream.c
+++ b/sound/firewire/oxfw/oxfw_stream.c
@@ -8,6 +8,7 @@
 
 #include "oxfw.h"
 
+#define AVC_GENERIC_FRAME_MAXIMUM_BYTES	512
 #define CALLBACK_TIMEOUT	200
 
 /*
@@ -24,6 +25,19 @@ static const unsigned int oxfw_rate_table[] = {
 	[5] = 192000,
 };
 
+/*
+ * See Table 5.7 – Sampling frequency for Multi-bit Audio
+ * at AV/C Stream Format Information Specification 1.1 (Apr 2005, 1394TA)
+ */
+static const unsigned int avc_stream_rate_table[] = {
+	[0] = 0x02,
+	[1] = 0x03,
+	[2] = 0x04,
+	[3] = 0x0a,
+	[4] = 0x05,
+	[5] = 0x07,
+};
+
 int snd_oxfw_stream_init_simplex(struct snd_oxfw *oxfw)
 {
 	int err;
@@ -109,6 +123,28 @@ end:
 	return err;
 }
 
+static int check_connection_used_by_others(struct snd_oxfw *oxfw)
+{
+	struct cmp_connection *conn;
+	struct amdtp_stream *stream;
+	bool used;
+	int err;
+
+	stream = &oxfw->rx_stream;
+	conn = &oxfw->in_conn;
+
+	err = cmp_connection_check_used(conn, &used);
+	if ((err >= 0) && used && !amdtp_stream_running(stream)) {
+		dev_err(&oxfw->unit->device,
+			"Connection established by others: %cPCR[%d]\n",
+			(conn->direction == CMP_OUTPUT) ? 'o' : 'i',
+			conn->pcr_index);
+		err = -EBUSY;
+	}
+
+	return err;
+}
+
 int snd_oxfw_stream_start_simplex(struct snd_oxfw *oxfw, unsigned int rate,
 				  unsigned int pcm_channels)
 {
@@ -117,6 +153,14 @@ int snd_oxfw_stream_start_simplex(struct snd_oxfw *oxfw, unsigned int rate,
 
 	mutex_lock(&oxfw->mutex);
 
+	/*
+	 * Considering JACK/FFADO streaming:
+	 * TODO: This can be removed hwdep functionality becomes popular.
+	 */
+	err = check_connection_used_by_others(oxfw);
+	if (err < 0)
+		goto end;
+
 	/* packet queueing error */
 	if (amdtp_streaming_error(&oxfw->rx_stream))
 		stop_stream(oxfw);
@@ -182,36 +226,221 @@ void snd_oxfw_stream_update_simplex(struct snd_oxfw *oxfw)
 	}
 }
 
-int firewave_stream_discover(struct snd_oxfw *oxfw)
+/*
+ * See Table 6.16 - AM824 Stream Format
+ *     Figure 6.19 - format_information field for AM824 Compound
+ * in AV/C Stream Format Information Specification 1.1 (Apr 2005, 1394TA)
+ * Also 'Clause 12 AM824 sequence adaption layers' in IEC 61883-6:2005
+ */
+static int parse_stream_formation(u8 *buf, unsigned int len,
+				  struct snd_oxfw_stream_formation *formation)
 {
-	/* 6 channels for PCM at 32.0/44.1/48.0/96.0kHz */
-	oxfw->rx_stream_formations[0].rate = oxfw_rate_table[0];
-	oxfw->rx_stream_formations[1].rate = oxfw_rate_table[1];
-	oxfw->rx_stream_formations[2].rate = oxfw_rate_table[2];
-	oxfw->rx_stream_formations[3].rate = oxfw_rate_table[4];
-	oxfw->rx_stream_formations[0].pcm = 6;
-	oxfw->rx_stream_formations[1].pcm = 6;
-	oxfw->rx_stream_formations[2].pcm = 6;
-	oxfw->rx_stream_formations[3].pcm = 6;
-
-	/* 2 channels for PCM at 48.0/96.0kHz */
-	oxfw->rx_stream_formations[4].rate = oxfw_rate_table[2];
-	oxfw->rx_stream_formations[5].rate = oxfw_rate_table[4];
-	oxfw->rx_stream_formations[4].pcm = 2;
-	oxfw->rx_stream_formations[5].pcm = 2;
+	unsigned int i, e, channels, format;
+
+	if (len < 3)
+		return -EINVAL;
+
+	/*
+	 * this module can support a hierarchy combination that:
+	 *  Root:	Audio and Music (0x90)
+	 *  Level 1:	AM824 Compound  (0x40)
+	 */
+	if ((buf[0] != 0x90) || (buf[1] != 0x40))
+		return -ENOSYS;
+
+	/* check the sampling rate */
+	for (i = 0; i < ARRAY_SIZE(avc_stream_rate_table); i++) {
+		if (buf[2] == avc_stream_rate_table[i])
+			break;
+	}
+	if (i == ARRAY_SIZE(avc_stream_rate_table))
+		return -ENOSYS;
+
+	memset(formation, 0, sizeof(struct snd_oxfw_stream_formation));
+	formation->rate = oxfw_rate_table[i];
+
+	for (e = 0; e < buf[4]; e++) {
+		channels = buf[5 + e * 2];
+		format = buf[6 + e * 2];
+
+		switch (format) {
+		/* IEC 60958 Conformant, currently handled as MBLA */
+		case 0x00:
+		/* Multi Bit Linear Audio (Raw) */
+		case 0x06:
+			formation->pcm += channels;
+			break;
+		/* MIDI Conformant */
+		case 0x0d:
+			formation->midi += channels;
+			break;
+		/* IEC 61937-3 to 7 */
+		case 0x01:
+		case 0x02:
+		case 0x03:
+		case 0x04:
+		case 0x05:
+		/* Multi Bit Linear Audio */
+		case 0x07:	/* DVD-Audio */
+		case 0x0c:	/* High Precision */
+		/* One Bit Audio */
+		case 0x08:	/* (Plain) Raw */
+		case 0x09:	/* (Plain) SACD */
+		case 0x0a:	/* (Encoded) Raw */
+		case 0x0b:	/* (Encoded) SACD */
+		/* SMPTE Time-Code conformant */
+		case 0x0e:
+		/* Sample Count */
+		case 0x0f:
+		/* Anciliary Data */
+		case 0x10:
+		/* Synchronization Stream (Stereo Raw audio) */
+		case 0x40:
+		/* Don't care */
+		case 0xff:
+		default:
+			return -ENOSYS;	/* not supported */
+		}
+	}
+
+	if (formation->pcm  > AMDTP_MAX_CHANNELS_FOR_PCM ||
+	    formation->midi > AMDTP_MAX_CHANNELS_FOR_MIDI)
+		return -ENOSYS;
 
 	return 0;
 }
 
-int lacie_speakers_stream_discover(struct snd_oxfw *oxfw)
+static int
+assume_stream_formations(struct snd_oxfw *oxfw, enum avc_general_plug_dir dir,
+			 unsigned int pid, u8 *buf, unsigned int *len,
+			 struct snd_oxfw_stream_formation *formations)
 {
-	unsigned int i;
+	unsigned int rate, pcm_channels, midi_channels, i, eid;
+	int err;
 
-	/* 2 channels for MBLA at 32.0/44.1/48.0/88.2/96.0kHz */
-	for (i = 0; i < 5; i++) {
-		oxfw->rx_stream_formations[i].rate = oxfw_rate_table[i];
-		oxfw->rx_stream_formations[i].pcm = 2;
+	/* get formation at current sampling rate */
+	err = avc_stream_get_format_single(oxfw->unit, dir, pid, buf, len);
+	if (err < 0) {
+		dev_err(&oxfw->unit->device,
+		"fail to get current stream format for isoc %s plug %d:%d\n",
+			(dir == AVC_GENERAL_PLUG_DIR_IN) ? "in" : "out",
+			pid, err);
+		goto end;
 	}
 
-	return 0;
+	/* parse and set stream formation */
+	eid = 0;
+	err = parse_stream_formation(buf, *len, &formations[eid]);
+	if (err < 0)
+		goto end;
+
+	rate = formations[eid].rate;
+	pcm_channels = formations[eid].pcm;
+	midi_channels = formations[eid].midi;
+
+	/* apply the formation for each available sampling rate */
+	for (i = 0; i < ARRAY_SIZE(oxfw_rate_table); i++) {
+		if (rate == oxfw_rate_table[i])
+			continue;
+
+		err = avc_general_inquiry_sig_fmt(oxfw->unit,
+						  oxfw_rate_table[i],
+						  dir, pid);
+		if (err < 0)
+			continue;
+
+		eid++;
+		formations[eid].rate = oxfw_rate_table[i];
+		formations[eid].pcm = pcm_channels;
+		formations[eid].midi = midi_channels;
+	}
+
+	err = 0;
+end:
+	return err;
+}
+
+static int fill_stream_formations(struct snd_oxfw *oxfw,
+				  enum avc_general_plug_dir dir,
+				  unsigned short pid)
+{
+	u8 *buf;
+	struct snd_oxfw_stream_formation *formations;
+	unsigned int len, eid = 0;
+	int err;
+
+	buf = kmalloc(AVC_GENERIC_FRAME_MAXIMUM_BYTES, GFP_KERNEL);
+	if (buf == NULL)
+		return -ENOMEM;
+
+	formations = oxfw->rx_stream_formations;
+
+	/* get first entry */
+	len = AVC_GENERIC_FRAME_MAXIMUM_BYTES;
+	err = avc_stream_get_format_list(oxfw->unit, dir, 0, buf, &len, 0);
+	if (err == -ENOSYS) {
+		/* LIST subfunction is not implemented */
+		len = AVC_GENERIC_FRAME_MAXIMUM_BYTES;
+		err = assume_stream_formations(oxfw, dir, pid, buf, &len,
+					       formations);
+		goto end;
+	} else if (err < 0) {
+		dev_err(&oxfw->unit->device,
+			"fail to get stream format %d for isoc %s plug %d:%d\n",
+			eid, (dir == AVC_GENERAL_PLUG_DIR_IN) ? "in" : "out",
+			pid, err);
+		goto end;
+	}
+
+	/* LIST subfunction is implemented */
+	while (eid < SND_OXFW_STREAM_FORMAT_ENTRIES) {
+		/* parse and set stream formation */
+		err = parse_stream_formation(buf, len, &formations[eid]);
+		if (err < 0)
+			break;
+
+		/* get next entry */
+		len = AVC_GENERIC_FRAME_MAXIMUM_BYTES;
+		err = avc_stream_get_format_list(oxfw->unit, dir, 0,
+						 buf, &len, ++eid);
+		/* No entries remained. */
+		if (err == -EINVAL) {
+			err = 0;
+			break;
+		} else if (err < 0) {
+			dev_err(&oxfw->unit->device,
+			"fail to get stream format %d for isoc %s plug %d:%d\n",
+				eid, (dir == AVC_GENERAL_PLUG_DIR_IN) ? "in" :
+									"out",
+				pid, err);
+			break;
+		}
+	}
+end:
+	kfree(buf);
+	return err;
+}
+
+int snd_oxfw_stream_discover(struct snd_oxfw *oxfw)
+{
+	u8 plugs[AVC_PLUG_INFO_BUF_BYTES];
+	int err;
+
+	/* the number of plugs for isoc in/out, ext in/out  */
+	err = avc_general_get_plug_info(oxfw->unit, 0x1f, 0x07, 0x00, plugs);
+	if (err < 0) {
+		dev_err(&oxfw->unit->device,
+		"fail to get info for isoc/external in/out plugs: %d\n",
+			err);
+		goto end;
+	} else if (plugs[0] == 0) {
+		err = -ENOSYS;
+		goto end;
+	}
+
+	/* use iPCR[0] if exists */
+	if (plugs[0] > 0)
+		err = fill_stream_formations(oxfw, AVC_GENERAL_PLUG_DIR_IN, 0);
+end:
+	return err;
 }
