ALSA: fireface: update isochronous resources when starting packet streaming after...
authorTakashi Sakamoto <o-takashi@sakamocchi.jp>
Sun, 2 Jun 2019 07:12:57 +0000 (16:12 +0900)
committerTakashi Iwai <tiwai@suse.de>
Tue, 11 Jun 2019 09:36:25 +0000 (11:36 +0200)
commitb88f4d7c3812e3f3f746895cc4475b02c530303e
tree0926c390748d8461131328130a4532f49d113107
parent55162d2bb0e86b2d0f87a82713b1e7ee761bf8a8
ALSA: fireface: update isochronous resources when starting packet streaming after bus-reset

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>
sound/firewire/fireface/ff-protocol-former.c
sound/firewire/fireface/ff-protocol-latter.c
sound/firewire/fireface/ff-stream.c