ALSA: fireface: allocate isochronous resources in mode-specific implementation

The way to maintain isochronous resources on bus is different between
Fireface 400/800.

This commit is a preparation. This commit moves a function to allocate resource to
model-dependent implementation.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/firewire/fireface/ff-protocol-ff400.c

@@ -15,19 +15,60 @@
 #define FF400_TX_PACKET_FORMAT	0x00008010050cull
 #define FF400_ISOC_COMM_STOP	0x000080100510ull
 
-static int ff400_begin_session(struct snd_ff *ff, unsigned int rate)
+/*
+ * Fireface 400 manages isochronous channel number in 3 bit field. Therefore,
+ * we can allocate between 0 and 7 channel.
+ */
+static int keep_resources(struct snd_ff *ff, unsigned int rate)
 {
-	__le32 reg;
-	int i, err;
+	enum snd_ff_stream_mode mode;
+	int i;
+	int err;
 
-	/* Check whether the given value is supported or not. */
+	// Check whether the given value is supported or not.
 	for (i = 0; i < CIP_SFC_COUNT; i++) {
 		if (amdtp_rate_table[i] == rate)
 			break;
 	}
-	if (i == CIP_SFC_COUNT)
+	if (i >= CIP_SFC_COUNT)
 		return -EINVAL;
 
+	err = snd_ff_stream_get_multiplier_mode(i, &mode);
+	if (err < 0)
+		return err;
+
+	/* Keep resources for in-stream. */
+	ff->tx_resources.channels_mask = 0x00000000000000ffuLL;
+	err = fw_iso_resources_allocate(&ff->tx_resources,
+			amdtp_stream_get_max_payload(&ff->tx_stream),
+			fw_parent_device(ff->unit)->max_speed);
+	if (err < 0)
+		return err;
+
+	/* Keep resources for out-stream. */
+	err = amdtp_ff_set_parameters(&ff->rx_stream, rate,
+				      ff->spec->pcm_playback_channels[mode]);
+	if (err < 0)
+		return err;
+	ff->rx_resources.channels_mask = 0x00000000000000ffuLL;
+	err = fw_iso_resources_allocate(&ff->rx_resources,
+			amdtp_stream_get_max_payload(&ff->rx_stream),
+			fw_parent_device(ff->unit)->max_speed);
+	if (err < 0)
+		fw_iso_resources_free(&ff->tx_resources);
+
+	return err;
+}
+
+static int ff400_begin_session(struct snd_ff *ff, unsigned int rate)
+{
+	__le32 reg;
+	int err;
+
+	err = keep_resources(ff, rate);
+	if (err < 0)
+		return err;
+
 	/* Set the number of data blocks transferred in a second. */
 	reg = cpu_to_le32(rate);
 	err = snd_fw_transaction(ff->unit, TCODE_WRITE_QUADLET_REQUEST,

sound/firewire/fireface/ff-stream.c

@@ -31,54 +31,6 @@ int snd_ff_stream_get_multiplier_mode(enum cip_sfc sfc,
 	return 0;
 }
 
-/*
- * Fireface 400 manages isochronous channel number in 3 bit field. Therefore,
- * we can allocate between 0 and 7 channel.
- */
-static int keep_resources(struct snd_ff *ff, unsigned int rate)
-{
-	enum snd_ff_stream_mode mode;
-	int i;
-	int err;
-
-	for (i = 0; i < CIP_SFC_COUNT; ++i) {
-		if (amdtp_rate_table[i] == rate)
-			break;
-	}
-	if (i == CIP_SFC_COUNT)
-		return -EINVAL;
-
-	err = snd_ff_stream_get_multiplier_mode(i, &mode);
-	if (err < 0)
-		return err;
-
-	/* Keep resources for in-stream. */
-	err = amdtp_ff_set_parameters(&ff->tx_stream, rate,
-				      ff->spec->pcm_capture_channels[mode]);
-	if (err < 0)
-		return err;
-	ff->tx_resources.channels_mask = 0x00000000000000ffuLL;
-	err = fw_iso_resources_allocate(&ff->tx_resources,
-			amdtp_stream_get_max_payload(&ff->tx_stream),
-			fw_parent_device(ff->unit)->max_speed);
-	if (err < 0)
-		return err;
-
-	/* Keep resources for out-stream. */
-	err = amdtp_ff_set_parameters(&ff->rx_stream, rate,
-				      ff->spec->pcm_playback_channels[mode]);
-	if (err < 0)
-		return err;
-	ff->rx_resources.channels_mask = 0x00000000000000ffuLL;
-	err = fw_iso_resources_allocate(&ff->rx_resources,
-			amdtp_stream_get_max_payload(&ff->rx_stream),
-			fw_parent_device(ff->unit)->max_speed);
-	if (err < 0)
-		fw_iso_resources_free(&ff->tx_resources);
-
-	return err;
-}
-
 static void release_resources(struct snd_ff *ff)
 {
 	fw_iso_resources_free(&ff->tx_resources);
@@ -214,9 +166,29 @@ int snd_ff_stream_start_duplex(struct snd_ff *ff, unsigned int rate)
 	 * packets. Then, the device transfers packets.
 	 */
 	if (!amdtp_stream_running(&ff->rx_stream)) {
-		err = keep_resources(ff, rate);
+		enum snd_ff_stream_mode mode;
+		int i;
+
+		for (i = 0; i < CIP_SFC_COUNT; ++i) {
+			if (amdtp_rate_table[i] == rate)
+				break;
+		}
+		if (i >= CIP_SFC_COUNT)
+			return -EINVAL;
+
+		err = snd_ff_stream_get_multiplier_mode(i, &mode);
 		if (err < 0)
-			goto error;
+			return err;
+
+		err = amdtp_ff_set_parameters(&ff->tx_stream, rate,
+					ff->spec->pcm_capture_channels[mode]);
+		if (err < 0)
+			return err;
+
+		err = amdtp_ff_set_parameters(&ff->rx_stream, rate,
+					ff->spec->pcm_playback_channels[mode]);
+		if (err < 0)
+			return err;
 
 		err = ff->spec->protocol->begin_session(ff, rate);
 		if (err < 0)