After bus reset, isochronous resource manager releases all of allocated isochronous resources. The nodes to transfer isochronous packet 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 --- sound/firewire/dice/dice-stream.c | 10 ++++++++++ 1 file changed, 10 insertions(+)
diff --git a/sound/firewire/dice/dice-stream.c b/sound/firewire/dice/dice-stream.c index 6bbf7421a53c..f61b99a72655 100644 --- a/sound/firewire/dice/dice-stream.c +++ b/sound/firewire/dice/dice-stream.c @@ -399,6 +399,7 @@ static int start_streams(struct snd_dice *dice, enum amdtp_stream_direction dir, */ int snd_dice_stream_start_duplex(struct snd_dice *dice) { + unsigned int generation = dice->rx_resources[0].generation; struct reg_params tx_params, rx_params; unsigned int i; unsigned int rate; @@ -421,6 +422,15 @@ int snd_dice_stream_start_duplex(struct snd_dice *dice) } }
+ if (generation != fw_parent_device(dice->unit)->card->generation) { + for (i = 0; i < MAX_STREAMS; ++i) { + if (i < tx_params.count) + fw_iso_resources_update(dice->tx_resources + i); + if (i < rx_params.count) + fw_iso_resources_update(dice->rx_resources + i); + } + } + // Check required streams are running or not. err = snd_dice_transaction_get_rate(dice, &rate); if (err < 0)