[ALSA] Remove PCM xfer_align sw params

The xfer_align sw_params parameter has never been used in a sane manner,
and no one understands what this does exactly.  The current
implementation looks also buggy because it allows write of shorter size
than xfer_align.  So, if you do partial writes, the write isn't actually
aligned at all.
Removing this parameter will make some pcm_lib_* code more readable
(and less buggy).

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>

1 files changed, 4 insertions, 14 deletions

diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c
index f9f9b3fe956e..c1c1556105c0 100644
--- a/sound/core/pcm_lib.c
+++ b/sound/core/pcm_lib.c
@@ -1628,8 +1628,6 @@ static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
 
         if (size == 0)
                 return 0;
-        if (size > runtime->xfer_align)
-                size -= size % runtime->xfer_align;
 
         snd_pcm_stream_lock_irq(substream);
         switch (runtime->status->state) {
@@ -1657,9 +1655,7 @@ static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
                 avail = snd_pcm_playback_avail(runtime);
                 if (!avail ||
                     (snd_pcm_running(substream) &&
-                     ((avail < runtime->control->avail_min && size > avail) ||
-                      (size >= runtime->xfer_align &&
-                       avail < runtime->xfer_align)))) {
+                     (avail < runtime->control->avail_min && size > avail))) {
                         wait_queue_t wait;
                         enum { READY, SIGNALED, ERROR, SUSPENDED, EXPIRED, DROPPED } state;
                         long tout;
@@ -1731,8 +1727,6 @@ static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
                                 break;
                         }
                 }
-                if (avail > runtime->xfer_align)
-                        avail -= avail % runtime->xfer_align;
                 frames = size > avail ? avail : size;
                 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
                 if (frames > cont)
@@ -1900,8 +1894,6 @@ static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
 
         if (size == 0)
                 return 0;
-        if (size > runtime->xfer_align)
-                size -= size % runtime->xfer_align;
 
         snd_pcm_stream_lock_irq(substream);
         switch (runtime->status->state) {
@@ -1936,12 +1928,12 @@ static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
               __draining:
                 avail = snd_pcm_capture_avail(runtime);
                 if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
-                        if (avail < runtime->xfer_align) {
+                        if (!avail) {
                                 err = -EPIPE;
                                 goto _end_unlock;
                         }
-                } else if ((avail < runtime->control->avail_min && size > avail) ||
-                           (size >= runtime->xfer_align && avail < runtime->xfer_align)) {
+                } else if (avail < runtime->control->avail_min &&
+                           size > avail) {
                         wait_queue_t wait;
                         enum { READY, SIGNALED, ERROR, SUSPENDED, EXPIRED, DROPPED } state;
                         long tout;
@@ -2014,8 +2006,6 @@ static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
                                 break;
                         }
                 }
-                if (avail > runtime->xfer_align)
-                        avail -= avail % runtime->xfer_align;
                 frames = size > avail ? avail : size;
                 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
                 if (frames > cont)