[alsa-devel] [PATCH 01/16] ALSA: pcm: Introduce copy_silence PCM ops
Takashi Iwai
tiwai at suse.de
Sun May 21 22:09:35 CEST 2017
For supporting the explicit in-kernel copy of PCM buffer data, and
also for reducing the redundant codes for both PCM copy and silence
callbacks, a new ops copy_silence is introduced in this patch. This
is supposed to serve for both copy and silence operations. The
silence operation is distinguished by NULL buffer passed (required
only in playback direction).
Also, the callback receives a new boolean flag, in_kernel, which
indicates that the callback gets called for copying the data from/to
the kernel buffer instead of the user-space buffer. The in_kernel
flag will be used mainly in PCM OSS code for the on-the-fly
conversion. As this patch stands, only in_kernel=false is passed.
The actual usage of in_kernel=true will be introduced later.
Signed-off-by: Takashi Iwai <tiwai at suse.de>
---
include/sound/pcm.h | 3 +++
sound/core/pcm_lib.c | 74 +++++++++++++++++++++++++++++++++++++++++-----------
sound/soc/soc-pcm.c | 1 +
3 files changed, 63 insertions(+), 15 deletions(-)
diff --git a/include/sound/pcm.h b/include/sound/pcm.h
index c609b891c4c2..b9dd813dd885 100644
--- a/include/sound/pcm.h
+++ b/include/sound/pcm.h
@@ -83,6 +83,9 @@ 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 (*copy_silence)(struct snd_pcm_substream *substream, int channel,
+ snd_pcm_uframes_t pos, void __user *buf,
+ snd_pcm_uframes_t count, bool in_kernel);
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..b720cbda017f 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 +111,35 @@ 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->copy_silence) {
+ err = substream->ops->copy_silence(substream,
+ -1, ofs, NULL, transfer, false);
+ 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->copy_silence) {
+ for (c = 0; c < channels; ++c) {
+ err = substream->ops->copy_silence(substream,
+ c, ofs, NULL, transfer, false);
+ snd_BUG_ON(err < 0);
+ }
+ } else if (substream->ops->silence) {
for (c = 0; c < channels; ++c) {
- int err;
err = substream->ops->silence(substream, c, ofs, transfer);
snd_BUG_ON(err < 0);
}
} else {
size_t dma_csize = runtime->dma_bytes / channels;
for (c = 0; c < channels; ++c) {
- char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, ofs);
+ hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, ofs);
snd_pcm_format_set_silence(runtime->format, hwbuf, transfer);
}
}
@@ -1995,7 +2005,12 @@ static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
struct snd_pcm_runtime *runtime = substream->runtime;
int err;
char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
- if (substream->ops->copy) {
+ if (substream->ops->copy_silence) {
+ err = substream->ops->copy_silence(substream, -1, hwoff, buf,
+ frames, false);
+ if (err < 0)
+ return err;
+ } else if (substream->ops->copy) {
if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
return err;
} else {
@@ -2119,7 +2134,8 @@ static int pcm_sanity_check(struct snd_pcm_substream *substream)
if (PCM_RUNTIME_CHECK(substream))
return -ENXIO;
runtime = substream->runtime;
- if (snd_BUG_ON(!substream->ops->copy && !runtime->dma_area))
+ if (snd_BUG_ON(!substream->ops->copy_silence && !substream->ops->copy
+ && !runtime->dma_area))
return -EINVAL;
if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
return -EBADFD;
@@ -2156,8 +2172,21 @@ static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
int err;
void __user **bufs = (void __user **)data;
int channels = runtime->channels;
+ char __user *buf;
int c;
- if (substream->ops->copy) {
+
+ if (substream->ops->copy_silence) {
+ for (c = 0; c < channels; ++c, ++bufs) {
+ if (!*bufs)
+ buf = NULL;
+ else
+ buf = *bufs + samples_to_bytes(runtime, off);
+ err = substream->ops->copy_silence(substream, c, hwoff,
+ buf, frames, false);
+ if (err < 0)
+ return err;
+ }
+ } else if (substream->ops->copy) {
if (snd_BUG_ON(!substream->ops->silence))
return -EINVAL;
for (c = 0; c < channels; ++c, ++bufs) {
@@ -2165,7 +2194,7 @@ static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
return err;
} else {
- char __user *buf = *bufs + samples_to_bytes(runtime, off);
+ buf = *bufs + samples_to_bytes(runtime, off);
if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
return err;
}
@@ -2217,7 +2246,12 @@ static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream,
struct snd_pcm_runtime *runtime = substream->runtime;
int err;
char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
- if (substream->ops->copy) {
+ if (substream->ops->copy_silence) {
+ err = substream->ops->copy_silence(substream, -1, hwoff, buf,
+ frames, false);
+ if (err < 0)
+ return err;
+ } else if (substream->ops->copy) {
if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
return err;
} else {
@@ -2365,10 +2399,22 @@ static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
int err;
void __user **bufs = (void __user **)data;
int channels = runtime->channels;
+ char __user *buf;
+ char *hwbuf;
int c;
- if (substream->ops->copy) {
+
+ if (substream->ops->copy_silence) {
+ for (c = 0; c < channels; ++c, ++bufs) {
+ if (!*bufs)
+ continue;
+ buf = *bufs + samples_to_bytes(runtime, off);
+ err = substream->ops->copy_silence(substream, c, hwoff,
+ buf, frames, false);
+ if (err < 0)
+ return err;
+ }
+ } else if (substream->ops->copy) {
for (c = 0; c < channels; ++c, ++bufs) {
- char __user *buf;
if (*bufs == NULL)
continue;
buf = *bufs + samples_to_bytes(runtime, off);
@@ -2378,8 +2424,6 @@ static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
} else {
snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
for (c = 0; c < channels; ++c, ++bufs) {
- char *hwbuf;
- char __user *buf;
if (*bufs == NULL)
continue;
diff --git a/sound/soc/soc-pcm.c b/sound/soc/soc-pcm.c
index efc5831f205d..3cfb9aa1203b 100644
--- a/sound/soc/soc-pcm.c
+++ b/sound/soc/soc-pcm.c
@@ -2743,6 +2743,7 @@ int soc_new_pcm(struct snd_soc_pcm_runtime *rtd, int num)
if (platform->driver->ops) {
rtd->ops.ack = platform->driver->ops->ack;
+ rtd->ops.copy_silence = platform->driver->ops->copy_silence;
rtd->ops.copy = platform->driver->ops->copy;
rtd->ops.silence = platform->driver->ops->silence;
rtd->ops.page = platform->driver->ops->page;
--
2.13.0
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