From 665f3f506b1c2684d6f78d6d03c038d1712e561d Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Sat, 10 Dec 2011 02:12:31 +0100 Subject: [PATCH] staging: line6: wait for urbs in snd_line6_prepare() The .trigger() pcm callbacks are not allowed to block and cannot wait until urbs have completed. We need to ensure that stopping, preparing, and then restarting a stream always works. Currently the driver will sometimes return -EBUSY when restarting the stream because urbs have not completed yet. This can be triggered by jackd from userspace. The solution is to wait on urbs in the .prepare() pcm callback since blocking is allowed in that callback. This guarantees that all urbs are quiesced and ready to be submitted when the start trigger callback is invoked. Signed-off-by: Stefan Hajnoczi Signed-off-by: Markus Grabner Signed-off-by: Greg Kroah-Hartman --- drivers/staging/line6/pcm.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/drivers/staging/line6/pcm.c b/drivers/staging/line6/pcm.c index c3e5002c2af..68727b2dfb8 100644 --- a/drivers/staging/line6/pcm.c +++ b/drivers/staging/line6/pcm.c @@ -474,6 +474,20 @@ int snd_line6_prepare(struct snd_pcm_substream *substream) { struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream); + switch (substream->stream) { + case SNDRV_PCM_STREAM_PLAYBACK: + line6_unlink_wait_clear_audio_out_urbs(line6pcm); + break; + + case SNDRV_PCM_STREAM_CAPTURE: + line6_unlink_wait_clear_audio_in_urbs(line6pcm); + break; + + default: + MISSING_CASE; + } + + if (!test_and_set_bit(BIT_PREPARED, &line6pcm->flags)) { line6pcm->count_out = 0; line6pcm->pos_out = 0; -- 2.39.5