52 lines
1.7 KiB
Diff
52 lines
1.7 KiB
Diff
From: Stefan Hajnoczi <stefanha@gmail.com>
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Date: Sat, 10 Dec 2011 02:12:31 +0100
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Subject: [016/106] staging: line6: wait for urbs in snd_line6_prepare()
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commit 665f3f506b1c2684d6f78d6d03c038d1712e561d upstream.
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The .trigger() pcm callbacks are not allowed to block and cannot wait
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until urbs have completed. We need to ensure that stopping, preparing,
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and then restarting a stream always works.
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Currently the driver will sometimes return -EBUSY when restarting the
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stream because urbs have not completed yet. This can be triggered by
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jackd from userspace.
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The solution is to wait on urbs in the .prepare() pcm callback since
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blocking is allowed in that callback. This guarantees that all urbs are
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quiesced and ready to be submitted when the start trigger callback is
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invoked.
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Signed-off-by: Stefan Hajnoczi <stefanha@gmail.com>
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Signed-off-by: Markus Grabner <grabner@icg.tugraz.at>
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Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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---
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drivers/staging/line6/pcm.c | 14 ++++++++++++++
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1 file changed, 14 insertions(+)
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diff --git a/drivers/staging/line6/pcm.c b/drivers/staging/line6/pcm.c
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index c3e5002..68727b2 100644
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--- a/drivers/staging/line6/pcm.c
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+++ b/drivers/staging/line6/pcm.c
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@@ -474,6 +474,20 @@ int snd_line6_prepare(struct snd_pcm_substream *substream)
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{
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struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
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+ switch (substream->stream) {
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+ case SNDRV_PCM_STREAM_PLAYBACK:
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+ line6_unlink_wait_clear_audio_out_urbs(line6pcm);
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+ break;
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+
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+ case SNDRV_PCM_STREAM_CAPTURE:
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+ line6_unlink_wait_clear_audio_in_urbs(line6pcm);
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+ break;
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+
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+ default:
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+ MISSING_CASE;
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+ }
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+
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+
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if (!test_and_set_bit(BIT_PREPARED, &line6pcm->flags)) {
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line6pcm->count_out = 0;
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line6pcm->pos_out = 0;
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