For supporting the explicit in-kernel copy of PCM buffer data, and
also for further code refactoring, three new PCM ops, copy_user,
copy_kernel and fill_silence, are introduced. The old copy and
silence ops will be deprecated and removed later once when all callers
are converted.
The copy_kernel ops is the new one, and it's supposed to transfer the
PCM data from the given kernel buffer to the hardware ring-buffer (or
vice-versa depending on the stream direction), while the copy_user ops
is equivalent with the former copy ops, to transfer the data from the
user-space buffer.
The major difference of the new copy_* and fill_silence ops from the
previous ops is that the new ops take bytes instead of frames for size
and position arguments. It has two merits: first, it allows the
callback implementation often simpler (just call directly memcpy() &
co), and second, it may unify the implementations of both interleaved
and non-interleaved cases, as we'll see in the later patch.
As of this stage, copy_kernel ops isn't referred yet, but only
copy_user is used.
Signed-off-by: Takashi Iwai
---
include/sound/pcm.h | 7 +
sound/core/pcm_lib.c | 89 +++-
sound/soc/soc-pcm.c | 3 ++
3 files changed, 84 insertions(+), 15 deletions(-)
diff --git a/include/sound/pcm.h b/include/sound/pcm.h
index c609b891c4c2..a065415191d8 100644
--- a/include/sound/pcm.h
+++ b/include/sound/pcm.h
@@ -83,6 +83,13 @@ struct snd_pcm_ops {
void __user *buf, snd_pcm_uframes_t count);
int (*silence)(struct snd_pcm_substream *substream, int channel,
snd_pcm_uframes_t pos, snd_pcm_uframes_t count);
+ int (*fill_silence)(struct snd_pcm_substream *substream, int channel,
+ unsigned long pos, unsigned long bytes);
+ int (*copy_user)(struct snd_pcm_substream *substream, int channel,
+unsigned long pos, void __user *buf,
+unsigned long bytes);
+ int (*copy_kernel)(struct snd_pcm_substream *substream, int channel,
+ unsigned long pos, void *buf, unsigned long bytes);
struct page *(*page)(struct snd_pcm_substream *substream,
unsigned long offset);
int (*mmap)(struct snd_pcm_substream *substream, struct vm_area_struct
*vma);
diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c
index ab4b1d1e44ee..9334fc2c20c8 100644
--- a/sound/core/pcm_lib.c
+++ b/sound/core/pcm_lib.c
@@ -55,6 +55,8 @@ void snd_pcm_playback_silence(struct snd_pcm_substream
*substream, snd_pcm_ufram
{
struct snd_pcm_runtime *runtime = substream->runtime;
snd_pcm_uframes_t frames, ofs, transfer;
+ char *hwbuf;
+ int err;
if (runtime->silence_size < runtime->boundary) {
snd_pcm_sframes_t noise_dist, n;
@@ -109,27 +111,37 @@ void snd_pcm_playback_silence(struct snd_pcm_substream
*substream, snd_pcm_ufram
transfer = ofs + frames > runtime->buffer_size ?
runtime->buffer_size - ofs : frames;
if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED) {
- if (substream->ops->silence) {
- int err;
+ if (substream->ops->fill_silence) {
+ err = substream->ops->fill_silence(substream, 0,
+
frames_to_bytes(runtime, ofs),
+
frames_to_bytes(runtime, transfer));
+ snd_BUG_ON(err < 0);
+ } else if (substream->ops->silence) {
err = substream->ops->silence(substream, -1,
ofs, transfer);
snd_BUG_ON(err < 0);
} else {
- char *hwbuf = runtime->dma_area +
frames_to_bytes(runtime, ofs);
+ hwbuf = runtime->dma_area +
frames_to_bytes(runtime, ofs);
snd_pcm_format_set_silence(runtime->format,
hwbuf, transfer * runtime->channels);
}
} else {
unsigned int c;
unsigned int channels = runtime->channels;
- if (substream->ops->silence) {
+ if (substream->ops->fill_silence) {
+ for (c = 0; c < channels; ++c) {
+ err =
substream->ops->fill_silence(substream, c,
+
samples_to_bytes(runtime, ofs),
+
samples_to_bytes(runtime, transfer));
+ snd_BUG_ON
