ALSA: bebob: code refactoring for model-dependent quirks

This commit adds enumeration and structure member as code refactoring
regarding to model-dependent quirks.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20210611035003.26852-4-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/firewire/bebob/bebob.c

@@ -159,6 +159,30 @@ check_audiophile_booted(struct fw_unit *unit)
 	return strncmp(name, "FW Audiophile Bootloader", 24) != 0;
 }
 
+static int detect_quirks(struct snd_bebob *bebob, const struct ieee1394_device_id *entry)
+{
+	if (entry->vendor_id == VEN_MAUDIO1) {
+		switch (entry->model_id) {
+		case MODEL_MAUDIO_PROFIRELIGHTBRIDGE:
+			// M-Audio ProFire Lightbridge has a quirk to transfer packets with
+			// discontinuous cycle or data block counter in early stage of packet
+			// streaming. The cycle span from the first packet with event is variable.
+			bebob->quirks |= SND_BEBOB_QUIRK_INITIAL_DISCONTINUOUS_DBC;
+			break;
+		case MODEL_MAUDIO_FW1814:
+		case MODEL_MAUDIO_PROJECTMIX:
+			// At high sampling rate, M-Audio special firmware transmits empty packet
+			// with the value of dbc incremented by 8.
+			bebob->quirks |= SND_BEBOB_QUIRK_WRONG_DBC;
+			break;
+		default:
+			break;
+		}
+	}
+
+	return 0;
+}
+
 static int bebob_probe(struct fw_unit *unit, const struct ieee1394_device_id *entry)
 {
 	unsigned int card_index;
@@ -219,6 +243,10 @@ static int bebob_probe(struct fw_unit *unit, const struct ieee1394_device_id *en
 	if (err < 0)
 		goto error;
 
+	err = detect_quirks(bebob, entry);
+	if (err < 0)
+		goto error;
+
 	if (bebob->spec == &maudio_special_spec) {
 		if (entry->model_id == MODEL_MAUDIO_FW1814)
 			err = snd_bebob_maudio_special_discover(bebob, true);
@@ -230,12 +258,6 @@ static int bebob_probe(struct fw_unit *unit, const struct ieee1394_device_id *en
 	if (err < 0)
 		goto error;
 
-	// M-Audio ProFire Lightbridge has a quirk to transfer packets with discontinuous cycle or
-	// data block counter in early stage of packet streaming. The cycle span from the first
-	// packet with event is variable.
-	if (entry->vendor_id == VEN_MAUDIO1 && entry->model_id == MODEL_MAUDIO_PROFIRELIGHTBRIDGE)
-		bebob->discontinuity_quirk = true;
-
 	err = snd_bebob_stream_init_duplex(bebob);
 	if (err < 0)
 		goto error;

sound/firewire/bebob/bebob.h

@@ -75,6 +75,11 @@ struct snd_bebob_spec {
 	const struct snd_bebob_meter_spec *meter;
 };
 
+enum snd_bebob_quirk {
+	SND_BEBOB_QUIRK_INITIAL_DISCONTINUOUS_DBC,
+	SND_BEBOB_QUIRK_WRONG_DBC,
+};
+
 struct snd_bebob {
 	struct snd_card *card;
 	struct fw_unit *unit;
@@ -84,6 +89,7 @@ struct snd_bebob {
 	spinlock_t lock;
 
 	const struct snd_bebob_spec *spec;
+	unsigned int quirks;	// Combination of snd_bebob_quirk enumerations.
 
 	unsigned int midi_input_ports;
 	unsigned int midi_output_ports;
@@ -109,8 +115,6 @@ struct snd_bebob {
 	/* for M-Audio special devices */
 	void *maudio_special_quirk;
 
-	bool discontinuity_quirk;
-
 	struct amdtp_domain domain;
 };
 

sound/firewire/bebob/bebob_stream.c

@@ -430,6 +430,7 @@ static int start_stream(struct snd_bebob *bebob, struct amdtp_stream *stream)
 
 static int init_stream(struct snd_bebob *bebob, struct amdtp_stream *stream)
 {
+	unsigned int flags = CIP_BLOCKING;
 	enum amdtp_stream_direction dir_stream;
 	struct cmp_connection *conn;
 	enum cmp_direction dir_conn;
@@ -445,24 +446,21 @@ static int init_stream(struct snd_bebob *bebob, struct amdtp_stream *stream)
 		dir_conn = CMP_INPUT;
 	}
 
+	if (stream == &bebob->tx_stream) {
+		if (bebob->quirks & SND_BEBOB_QUIRK_WRONG_DBC)
+			flags |= CIP_EMPTY_HAS_WRONG_DBC;
+	}
+
 	err = cmp_connection_init(conn, bebob->unit, dir_conn, 0);
 	if (err < 0)
 		return err;
 
-	err = amdtp_am824_init(stream, bebob->unit, dir_stream, CIP_BLOCKING);
+	err = amdtp_am824_init(stream, bebob->unit, dir_stream, flags);
 	if (err < 0) {
 		cmp_connection_destroy(conn);
 		return err;
 	}
 
-	if (stream == &bebob->tx_stream) {
-		// At high sampling rate, M-Audio special firmware transmits
-		// empty packet with the value of dbc incremented by 8 but the
-		// others are valid to IEC 61883-1.
-		if (bebob->maudio_special_quirk)
-			bebob->tx_stream.flags |= CIP_EMPTY_HAS_WRONG_DBC;
-	}
-
 	return 0;
 }
 
@@ -630,7 +628,7 @@ int snd_bebob_stream_start_duplex(struct snd_bebob *bebob)
 		if (err < 0)
 			goto error;
 
-		if (!bebob->discontinuity_quirk)
+		if (!(bebob->quirks & SND_BEBOB_QUIRK_INITIAL_DISCONTINUOUS_DBC))
 			tx_init_skip_cycles = 0;
 		else
 			tx_init_skip_cycles = 16000;