[PATCH v2 18/25] ASoC: component: Add generic PCM copy ops

From: Takashi Iwai
Date: Tue Aug 15 2023 - 15:03:54 EST


For following the ALSA PCM core change, a new PCM copy ops is added
toe ASoC component framework: snd_soc_component_driver receives the
copy ops, and snd_soc_pcm_component_copy() helper is provided.

This also fixes a long-standing potential bug where the ASoC driver
covers only copy_user PCM callback and misses the copy from kernel
pointers (such as OSS PCM layer), too.

As of this patch, the old copy_user is still kept, but it'll be
dropped later after all drivers are converted.

Reviewed-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
---
include/sound/soc-component.h | 7 +++++++
sound/soc/soc-component.c | 18 ++++++++++++++++++
sound/soc/soc-pcm.c | 4 +++-
3 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/include/sound/soc-component.h b/include/sound/soc-component.h
index 87f248a06271..8040f001f2fb 100644
--- a/include/sound/soc-component.h
+++ b/include/sound/soc-component.h
@@ -141,6 +141,10 @@ struct snd_soc_component_driver {
struct snd_pcm_substream *substream, int channel,
unsigned long pos, void __user *buf,
unsigned long bytes);
+ int (*copy)(struct snd_soc_component *component,
+ struct snd_pcm_substream *substream, int channel,
+ unsigned long pos, struct iov_iter *buf,
+ unsigned long bytes);
struct page *(*page)(struct snd_soc_component *component,
struct snd_pcm_substream *substream,
unsigned long offset);
@@ -512,6 +516,9 @@ int snd_soc_pcm_component_sync_stop(struct snd_pcm_substream *substream);
int snd_soc_pcm_component_copy_user(struct snd_pcm_substream *substream,
int channel, unsigned long pos,
void __user *buf, unsigned long bytes);
+int snd_soc_pcm_component_copy(struct snd_pcm_substream *substream,
+ int channel, unsigned long pos,
+ struct iov_iter *buf, unsigned long bytes);
struct page *snd_soc_pcm_component_page(struct snd_pcm_substream *substream,
unsigned long offset);
int snd_soc_pcm_component_mmap(struct snd_pcm_substream *substream,
diff --git a/sound/soc/soc-component.c b/sound/soc/soc-component.c
index 4356cc320fea..ffa2dd8a21ba 100644
--- a/sound/soc/soc-component.c
+++ b/sound/soc/soc-component.c
@@ -1052,6 +1052,24 @@ int snd_soc_pcm_component_sync_stop(struct snd_pcm_substream *substream)
return 0;
}

+int snd_soc_pcm_component_copy(struct snd_pcm_substream *substream,
+ int channel, unsigned long pos,
+ struct iov_iter *buf, unsigned long bytes)
+{
+ struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
+ struct snd_soc_component *component;
+ int i;
+
+ /* FIXME. it returns 1st copy now */
+ for_each_rtd_components(rtd, i, component)
+ if (component->driver->copy)
+ return soc_component_ret(component,
+ component->driver->copy(component, substream,
+ channel, pos, buf, bytes));
+
+ return -EINVAL;
+}
+
int snd_soc_pcm_component_copy_user(struct snd_pcm_substream *substream,
int channel, unsigned long pos,
void __user *buf, unsigned long bytes)
diff --git a/sound/soc/soc-pcm.c b/sound/soc/soc-pcm.c
index 8896227e4fb7..71403da28d37 100644
--- a/sound/soc/soc-pcm.c
+++ b/sound/soc/soc-pcm.c
@@ -2973,7 +2973,9 @@ int soc_new_pcm(struct snd_soc_pcm_runtime *rtd, int num)
rtd->ops.ioctl = snd_soc_pcm_component_ioctl;
if (drv->sync_stop)
rtd->ops.sync_stop = snd_soc_pcm_component_sync_stop;
- if (drv->copy_user)
+ if (drv->copy)
+ rtd->ops.copy = snd_soc_pcm_component_copy;
+ else if (drv->copy_user)
rtd->ops.copy_user = snd_soc_pcm_component_copy_user;
if (drv->page)
rtd->ops.page = snd_soc_pcm_component_page;
--
2.35.3