ALSA: fireface: update isochronous resources when starting packet streaming after...

After bus reset, isochronous resource manager releases all of allocated
isochronous resources. The nodes to restart packet streaming should
request reallocation of the resources.

However, between the bus-reset and invocation of 'struct fw_driver.update'
handler, ALSA PCM application can detect this situation by XRUN because
the target device cancelled to transmit packets once bus-reset occurs.

Due to the above mechanism, ALSA fireface driver just stops packet
streaming in the update handler, thus pcm.prepare handler should
request the reallocation.

This commit requests the reallocation in pcm.prepare callback when
bus generation is changed.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/firewire/fireface/ff-protocol-former.c b/sound/firewire/fireface/ff-protocol-former.c
index 0517eb718f542c39f3ccdd8f453505c3feed3051..bf44cad7985e080697563bdf56a0df34eba37196 100644 (file)
--- a/sound/firewire/fireface/ff-protocol-former.c
+++ b/sound/firewire/fireface/ff-protocol-former.c
@@ -374,8 +374,15 @@ static int ff800_allocate_resources(struct snd_ff *ff, unsigned int rate)
 
 static int ff800_begin_session(struct snd_ff *ff, unsigned int rate)
 {
+       unsigned int generation = ff->rx_resources.generation;
        __le32 reg;
 
+       if (generation != fw_parent_device(ff->unit)->card->generation) {
+               int err = fw_iso_resources_update(&ff->rx_resources);
+               if (err < 0)
+                       return err;
+       }
+
        reg = cpu_to_le32(0x80000000);
        reg |= cpu_to_le32(ff->tx_stream.data_block_quadlets);
        if (fw_parent_device(ff->unit)->max_speed == SCODE_800)
@@ -480,13 +487,22 @@ static int ff400_allocate_resources(struct snd_ff *ff, unsigned int rate)
 
 static int ff400_begin_session(struct snd_ff *ff, unsigned int rate)
 {
+       unsigned int generation = ff->rx_resources.generation;
        __le32 reg;
        int err;
 
-       /*
-        * Set isochronous channel and the number of quadlets of received
-        * packets.
-        */
+       if (generation != fw_parent_device(ff->unit)->card->generation) {
+               err = fw_iso_resources_update(&ff->tx_resources);
+               if (err < 0)
+                       return err;
+
+               err = fw_iso_resources_update(&ff->rx_resources);
+               if (err < 0)
+                       return err;
+       }
+
+       // Set isochronous channel and the number of quadlets of received
+       // packets.
        reg = cpu_to_le32(((ff->rx_stream.data_block_quadlets << 3) << 8) |
                          ff->rx_resources.channel);
        err = snd_fw_transaction(ff->unit, TCODE_WRITE_QUADLET_REQUEST,
@@ -494,11 +510,9 @@ static int ff400_begin_session(struct snd_ff *ff, unsigned int rate)
        if (err < 0)
                return err;
 
-       /*
-        * Set isochronous channel and the number of quadlets of transmitted
-        * packet.
-        */
-       /* TODO: investigate the purpose of this 0x80. */
+       // Set isochronous channel and the number of quadlets of transmitted
+       // packet.
+       // TODO: investigate the purpose of this 0x80.
        reg = cpu_to_le32((0x80 << 24) |
                          (ff->tx_resources.channel << 5) |
                          (ff->tx_stream.data_block_quadlets));
@@ -507,7 +521,7 @@ static int ff400_begin_session(struct snd_ff *ff, unsigned int rate)
        if (err < 0)
                return err;
 
-       /* Allow to transmit packets. */
+       // Allow to transmit packets.
        reg = cpu_to_le32(0x00000001);
        return snd_fw_transaction(ff->unit, TCODE_WRITE_QUADLET_REQUEST,
                                 FF400_ISOC_COMM_START, &reg, sizeof(reg), 0);

diff --git a/sound/firewire/fireface/ff-protocol-latter.c b/sound/firewire/fireface/ff-protocol-latter.c
index 3d12ba5b2a9bab77e2852c05ce439e837bbb8a8d..8d6ebb638e93e7d73b81be6b9dd96bae736a64bb 100644 (file)
--- a/sound/firewire/fireface/ff-protocol-latter.c
+++ b/sound/firewire/fireface/ff-protocol-latter.c
@@ -175,6 +175,7 @@ static int latter_allocate_resources(struct snd_ff *ff, unsigned int rate)
 
 static int latter_begin_session(struct snd_ff *ff, unsigned int rate)
 {
+       unsigned int generation = ff->rx_resources.generation;
        unsigned int flag;
        u32 data;
        __le32 reg;
@@ -189,6 +190,16 @@ static int latter_begin_session(struct snd_ff *ff, unsigned int rate)
        else
                return -EINVAL;
 
+       if (generation != fw_parent_device(ff->unit)->card->generation) {
+               err = fw_iso_resources_update(&ff->tx_resources);
+               if (err < 0)
+                       return err;
+
+               err = fw_iso_resources_update(&ff->rx_resources);
+               if (err < 0)
+                       return err;
+       }
+
        data = (ff->tx_resources.channel << 8) | ff->rx_resources.channel;
        reg = cpu_to_le32(data);
        err = snd_fw_transaction(ff->unit, TCODE_WRITE_QUADLET_REQUEST,

diff --git a/sound/firewire/fireface/ff-stream.c b/sound/firewire/fireface/ff-stream.c
index d9d1b469a8e917ade4438fd3027ef4964ee06840..4f40dfb11979555b86aff7cbec96d26ec319ada8 100644 (file)
--- a/sound/firewire/fireface/ff-stream.c
+++ b/sound/firewire/fireface/ff-stream.c
@@ -234,15 +234,12 @@ void snd_ff_stream_stop_duplex(struct snd_ff *ff)
 
 void snd_ff_stream_update_duplex(struct snd_ff *ff)
 {
-       /* The device discontinue to transfer packets.  */
+       // The device discontinue to transfer packets.
        amdtp_stream_pcm_abort(&ff->tx_stream);
        amdtp_stream_stop(&ff->tx_stream);
 
        amdtp_stream_pcm_abort(&ff->rx_stream);
        amdtp_stream_stop(&ff->rx_stream);
-
-       fw_iso_resources_update(&ff->tx_resources);
-       fw_iso_resources_update(&ff->rx_resources);
 }
 
 void snd_ff_stream_lock_changed(struct snd_ff *ff)