[alsa-devel] [PATCH 01/15] ALSA: firewire-tascam: code refactoring for registration of isochronous channels

This commit is a part of preparation to perform allocation/release of isochronous channels in pcm.hw_params/hw_free callbacks.

The registration of isochronous channels is done just after allocation of isochronous resources. This commit separates the registration just before starting packet streaming.

Signed-off-by: Takashi Sakamoto o-takashi@sakamocchi.jp --- sound/firewire/tascam/tascam-stream.c | 84 +++++++++++++-------------- 1 file changed, 40 insertions(+), 44 deletions(-)

diff --git a/sound/firewire/tascam/tascam-stream.c b/sound/firewire/tascam/tascam-stream.c index f1657a4e0621..7cddd9ece4ee 100644 --- a/sound/firewire/tascam/tascam-stream.c +++ b/sound/firewire/tascam/tascam-stream.c @@ -195,6 +195,19 @@ static void finish_session(struct snd_tscm *tscm) TSCM_ADDR_BASE + TSCM_OFFSET_ISOC_RX_ON, &reg, sizeof(reg), 0);

+ // Unregister channels. + reg = cpu_to_be32(0x00000000); + snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST, + TSCM_ADDR_BASE + TSCM_OFFSET_ISOC_TX_CH, + &reg, sizeof(reg), 0); + reg = cpu_to_be32(0x00000000); + snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST, + TSCM_ADDR_BASE + TSCM_OFFSET_UNKNOWN, + &reg, sizeof(reg), 0); + reg = cpu_to_be32(0x00000000); + snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST, + TSCM_ADDR_BASE + TSCM_OFFSET_ISOC_RX_CH, + &reg, sizeof(reg), 0); }

static int begin_session(struct snd_tscm *tscm) @@ -202,6 +215,30 @@ static int begin_session(struct snd_tscm *tscm) __be32 reg; int err;

+ // Register the isochronous channel for transmitting stream. + reg = cpu_to_be32(tscm->tx_resources.channel); + err = snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST, + TSCM_ADDR_BASE + TSCM_OFFSET_ISOC_TX_CH, + &reg, sizeof(reg), 0); + if (err < 0) + return err; + + // Unknown. + reg = cpu_to_be32(0x00000002); + err = snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST, + TSCM_ADDR_BASE + TSCM_OFFSET_UNKNOWN, + &reg, sizeof(reg), 0); + if (err < 0) + return err; + + // Register the isochronous channel for receiving stream. + reg = cpu_to_be32(tscm->rx_resources.channel); + err = snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST, + TSCM_ADDR_BASE + TSCM_OFFSET_ISOC_RX_CH, + &reg, sizeof(reg), 0); + if (err < 0) + return err; + reg = cpu_to_be32(0x00000001); err = snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST, TSCM_ADDR_BASE + TSCM_OFFSET_START_STREAMING, @@ -216,7 +253,7 @@ static int begin_session(struct snd_tscm *tscm) if (err < 0) return err;

- /* Set an option for unknown purpose. */ + // Set an option for unknown purpose. reg = cpu_to_be32(0x00002000); err = snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST, TSCM_ADDR_BASE + TSCM_OFFSET_SET_OPTION, @@ -224,7 +261,7 @@ static int begin_session(struct snd_tscm *tscm) if (err < 0) return err;

- /* Start multiplexing PCM samples on packets. */ + // Start multiplexing PCM samples on packets. reg = cpu_to_be32(0x00000001); return snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST, @@ -234,30 +271,13 @@ static int begin_session(struct snd_tscm *tscm)

static void release_resources(struct snd_tscm *tscm) { - __be32 reg; - - /* Unregister channels. */ - reg = cpu_to_be32(0x00000000); - snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST, - TSCM_ADDR_BASE + TSCM_OFFSET_ISOC_TX_CH, - &reg, sizeof(reg), 0); - reg = cpu_to_be32(0x00000000); - snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST, - TSCM_ADDR_BASE + TSCM_OFFSET_UNKNOWN, - &reg, sizeof(reg), 0); - reg = cpu_to_be32(0x00000000); - snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST, - TSCM_ADDR_BASE + TSCM_OFFSET_ISOC_RX_CH, - &reg, sizeof(reg), 0); - - /* Release isochronous resources. */ + // Release isochronous resources. fw_iso_resources_free(&tscm->tx_resources); fw_iso_resources_free(&tscm->rx_resources); }

static int keep_resources(struct snd_tscm *tscm, unsigned int rate) { - __be32 reg; int err;

/* Keep resources for in-stream. */ @@ -280,30 +300,6 @@ static int keep_resources(struct snd_tscm *tscm, unsigned int rate) if (err < 0) return err;

- /* Register the isochronous channel for transmitting stream. */ - reg = cpu_to_be32(tscm->tx_resources.channel); - err = snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST, - TSCM_ADDR_BASE + TSCM_OFFSET_ISOC_TX_CH, - &reg, sizeof(reg), 0); - if (err < 0) - goto error; - - /* Unknown */ - reg = cpu_to_be32(0x00000002); - err = snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST, - TSCM_ADDR_BASE + TSCM_OFFSET_UNKNOWN, - &reg, sizeof(reg), 0); - if (err < 0) - goto error; - - /* Register the isochronous channel for receiving stream. */ - reg = cpu_to_be32(tscm->rx_resources.channel); - err = snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST, - TSCM_ADDR_BASE + TSCM_OFFSET_ISOC_RX_CH, - &reg, sizeof(reg), 0); - if (err < 0) - goto error; - return 0; error: release_resources(tscm);