Remove ugly hack in rate plugin poll_descriptors callback

The rate plugin has ugly hacks in poll_descriptors callback to adjust
avail_min when partial read/write occurs.  This causes often unexpected
problems like XRUNs, especially with two-period cases.

Let's remove that beast, it's rather harmful than useful.

Signed-off-by: Stas Sergeev <stsp@aknet.ru>

diff --git a/src/pcm/pcm_rate.c b/src/pcm/pcm_rate.c
index 71d16bab541805a9d3647ebf9b8c16c11d063ade..aa1b36cca30a0a07777c7787963f98a1183d0c46 100644 (file)
--- a/src/pcm/pcm_rate.c
+++ b/src/pcm/pcm_rate.c
@@ -715,38 +715,6 @@ static snd_pcm_sframes_t snd_pcm_rate_forward(snd_pcm_t *pcm, snd_pcm_uframes_t
        return n;
 }
 
-static int snd_pcm_rate_poll_descriptors(snd_pcm_t *pcm, struct pollfd *pfds, unsigned int space)
-{
-       snd_pcm_rate_t *rate = pcm->private_data;
-       snd_pcm_uframes_t avail_min;
-       int ret, err;
-
-       ret = snd_pcm_generic_poll_descriptors(pcm, pfds, space);
-       if (ret < 0)
-               return ret;
-
-       avail_min = rate->appl_ptr % pcm->period_size;
-       if (avail_min > 0) {
-               recalc(pcm, &avail_min);
-               if (avail_min < rate->gen.slave->buffer_size &&
-                   avail_min != rate->gen.slave->period_size)
-                       avail_min++;    /* 1st small little rounding correction */
-               if (avail_min < rate->gen.slave->buffer_size &&
-                   avail_min != rate->gen.slave->period_size)
-                       avail_min++;    /* 2nd small little rounding correction */
-               avail_min += rate->orig_avail_min;
-       } else {
-               avail_min = rate->orig_avail_min;
-       }
-       if (rate->sw_params.avail_min == avail_min)
-               return ret;
-       rate->sw_params.avail_min = avail_min;
-       err = snd_pcm_sw_params(rate->gen.slave, &rate->sw_params);
-       if (err < 0)
-               return err;
-       return ret;
-}
-
 static int snd_pcm_rate_commit_area(snd_pcm_t *pcm, snd_pcm_rate_t *rate,
                                    snd_pcm_uframes_t appl_offset,
                                    snd_pcm_uframes_t size,
@@ -1229,7 +1197,7 @@ static snd_pcm_fast_ops_t snd_pcm_rate_fast_ops = {
        .avail_update = snd_pcm_rate_avail_update,
        .mmap_commit = snd_pcm_rate_mmap_commit,
        .poll_descriptors_count = snd_pcm_generic_poll_descriptors_count,
-       .poll_descriptors = snd_pcm_rate_poll_descriptors,
+       .poll_descriptors = snd_pcm_generic_poll_descriptors,
        .poll_revents = snd_pcm_rate_poll_revents,
 };