[alsa-devel] [PATCH] Fix forward/rewind support in iec958 plugin
Alexander E. Patrakov
patrakov at gmail.com
Wed Apr 23 20:40:27 CEST 2014
When forwarding or rewinding, the frame counter was not updated. This
could result in corrupted channel status words or misplaced Z-type
preamble.
---
I found the issue by inspecting the code. However, I have no hardware
to test this fix on.
src/pcm/pcm_iec958.c | 64 +++++++++++++++++++++++++++++++++++++++++++++-
src/pcm/pcm_plugin.c | 28 ++++++++++----------
src/pcm/pcm_plugin.h | 72 +++++++++++++++++++++++++++++++++++++++++++++++++---
3 files changed, 145 insertions(+), 19 deletions(-)
diff --git a/src/pcm/pcm_iec958.c b/src/pcm/pcm_iec958.c
index d81b0a1..facf683 100644
--- a/src/pcm/pcm_iec958.c
+++ b/src/pcm/pcm_iec958.c
@@ -416,6 +416,35 @@ static void snd_pcm_iec958_dump(snd_pcm_t *pcm, snd_output_t *out)
snd_pcm_dump(iec->plug.gen.slave, out);
}
+static snd_pcm_sframes_t snd_pcm_iec958_rewind(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
+{
+ unsigned int counter_decrement;
+ snd_pcm_iec958_t *iec = pcm->private_data;
+ snd_pcm_sframes_t result = snd_pcm_plugin_rewind(pcm, frames);
+ if (result <= 0)
+ return result;
+
+ counter_decrement = result % 192;
+ iec->counter += 192 - counter_decrement;
+ iec->counter %= 192;
+ return result;
+}
+
+static snd_pcm_sframes_t snd_pcm_iec958_forward(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
+
+{
+ unsigned int counter_increment;
+ snd_pcm_iec958_t *iec = pcm->private_data;
+ snd_pcm_sframes_t result = snd_pcm_plugin_rewind(pcm, frames);
+ if (result <= 0)
+ return result;
+
+ counter_increment = result % 192;
+ iec->counter += counter_increment;
+ iec->counter %= 192;
+ return result;
+}
+
static const snd_pcm_ops_t snd_pcm_iec958_ops = {
.close = snd_pcm_generic_close,
.info = snd_pcm_generic_info,
@@ -434,6 +463,39 @@ static const snd_pcm_ops_t snd_pcm_iec958_ops = {
.set_chmap = snd_pcm_generic_set_chmap,
};
+
+static const snd_pcm_fast_ops_t snd_pcm_iec958_fast_ops = {
+ .status = snd_pcm_plugin_status,
+ .state = snd_pcm_generic_state,
+ .hwsync = snd_pcm_generic_hwsync,
+ .delay = snd_pcm_plugin_delay,
+ .prepare = snd_pcm_plugin_prepare,
+ .reset = snd_pcm_plugin_reset,
+ .start = snd_pcm_generic_start,
+ .drop = snd_pcm_generic_drop,
+ .drain = snd_pcm_generic_drain,
+ .pause = snd_pcm_generic_pause,
+ .rewindable = snd_pcm_plugin_rewindable,
+ .rewind = snd_pcm_iec958_rewind,
+ .forwardable = snd_pcm_plugin_forwardable,
+ .forward = snd_pcm_iec958_forward,
+ .resume = snd_pcm_generic_resume,
+ .link = snd_pcm_generic_link,
+ .link_slaves = snd_pcm_generic_link_slaves,
+ .unlink = snd_pcm_generic_unlink,
+ .writei = snd_pcm_plugin_writei,
+ .writen = snd_pcm_plugin_writen,
+ .readi = snd_pcm_plugin_readi,
+ .readn = snd_pcm_plugin_readn,
+ .avail_update = snd_pcm_plugin_avail_update,
+ .mmap_commit = snd_pcm_plugin_mmap_commit,
+ .htimestamp = snd_pcm_generic_htimestamp,
+ .poll_descriptors_count = snd_pcm_generic_poll_descriptors_count,
+ .poll_descriptors = snd_pcm_generic_poll_descriptors,
+ .poll_revents = snd_pcm_generic_poll_revents,
+ .may_wait_for_avail_min = snd_pcm_generic_may_wait_for_avail_min,
+};
+
/**
* \brief Creates a new IEC958 subframe conversion PCM
* \param pcmp Returns created PCM handle
@@ -495,7 +557,7 @@ int snd_pcm_iec958_open(snd_pcm_t **pcmp, const char *name, snd_pcm_format_t sfo
return err;
}
pcm->ops = &snd_pcm_iec958_ops;
- pcm->fast_ops = &snd_pcm_plugin_fast_ops;
+ pcm->fast_ops = &snd_pcm_iec958_fast_ops;
pcm->private_data = iec;
pcm->poll_fd = slave->poll_fd;
pcm->poll_events = slave->poll_events;
diff --git a/src/pcm/pcm_plugin.c b/src/pcm/pcm_plugin.c
index 17157e8..022d908 100644
--- a/src/pcm/pcm_plugin.c
+++ b/src/pcm/pcm_plugin.c
@@ -137,7 +137,7 @@ void snd_pcm_plugin_init(snd_pcm_plugin_t *plugin)
snd_atomic_write_init(&plugin->watom);
}
-static int snd_pcm_plugin_delay(snd_pcm_t *pcm, snd_pcm_sframes_t *delayp)
+int snd_pcm_plugin_delay(snd_pcm_t *pcm, snd_pcm_sframes_t *delayp)
{
snd_pcm_plugin_t *plugin = pcm->private_data;
snd_pcm_sframes_t sd;
@@ -154,7 +154,7 @@ static int snd_pcm_plugin_delay(snd_pcm_t *pcm, snd_pcm_sframes_t *delayp)
return 0;
}
-static int snd_pcm_plugin_prepare(snd_pcm_t *pcm)
+int snd_pcm_plugin_prepare(snd_pcm_t *pcm)
{
snd_pcm_plugin_t *plugin = pcm->private_data;
int err;
@@ -175,7 +175,7 @@ static int snd_pcm_plugin_prepare(snd_pcm_t *pcm)
return 0;
}
-static int snd_pcm_plugin_reset(snd_pcm_t *pcm)
+int snd_pcm_plugin_reset(snd_pcm_t *pcm)
{
snd_pcm_plugin_t *plugin = pcm->private_data;
int err;
@@ -196,12 +196,12 @@ static int snd_pcm_plugin_reset(snd_pcm_t *pcm)
return 0;
}
-static snd_pcm_sframes_t snd_pcm_plugin_rewindable(snd_pcm_t *pcm)
+snd_pcm_sframes_t snd_pcm_plugin_rewindable(snd_pcm_t *pcm)
{
return snd_pcm_mmap_hw_avail(pcm);
}
-static snd_pcm_sframes_t snd_pcm_plugin_rewind(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
+snd_pcm_sframes_t snd_pcm_plugin_rewind(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
{
snd_pcm_plugin_t *plugin = pcm->private_data;
snd_pcm_sframes_t n = snd_pcm_mmap_hw_avail(pcm);
@@ -224,12 +224,12 @@ static snd_pcm_sframes_t snd_pcm_plugin_rewind(snd_pcm_t *pcm, snd_pcm_uframes_t
return (snd_pcm_sframes_t) sframes;
}
-static snd_pcm_sframes_t snd_pcm_plugin_forwardable(snd_pcm_t *pcm)
+snd_pcm_sframes_t snd_pcm_plugin_forwardable(snd_pcm_t *pcm)
{
return snd_pcm_mmap_avail(pcm);
}
-static snd_pcm_sframes_t snd_pcm_plugin_forward(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
+snd_pcm_sframes_t snd_pcm_plugin_forward(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
{
snd_pcm_plugin_t *plugin = pcm->private_data;
snd_pcm_sframes_t n = snd_pcm_mmap_avail(pcm);
@@ -347,7 +347,7 @@ static snd_pcm_sframes_t snd_pcm_plugin_read_areas(snd_pcm_t *pcm,
}
-static snd_pcm_sframes_t
+snd_pcm_sframes_t
snd_pcm_plugin_writei(snd_pcm_t *pcm, const void *buffer, snd_pcm_uframes_t size)
{
snd_pcm_channel_area_t areas[pcm->channels];
@@ -356,7 +356,7 @@ snd_pcm_plugin_writei(snd_pcm_t *pcm, const void *buffer, snd_pcm_uframes_t size
snd_pcm_plugin_write_areas);
}
-static snd_pcm_sframes_t
+snd_pcm_sframes_t
snd_pcm_plugin_writen(snd_pcm_t *pcm, void **bufs, snd_pcm_uframes_t size)
{
snd_pcm_channel_area_t areas[pcm->channels];
@@ -365,7 +365,7 @@ snd_pcm_plugin_writen(snd_pcm_t *pcm, void **bufs, snd_pcm_uframes_t size)
snd_pcm_plugin_write_areas);
}
-static snd_pcm_sframes_t
+snd_pcm_sframes_t
snd_pcm_plugin_readi(snd_pcm_t *pcm, void *buffer, snd_pcm_uframes_t size)
{
snd_pcm_channel_area_t areas[pcm->channels];
@@ -374,7 +374,7 @@ snd_pcm_plugin_readi(snd_pcm_t *pcm, void *buffer, snd_pcm_uframes_t size)
snd_pcm_plugin_read_areas);
}
-static snd_pcm_sframes_t
+snd_pcm_sframes_t
snd_pcm_plugin_readn(snd_pcm_t *pcm, void **bufs, snd_pcm_uframes_t size)
{
snd_pcm_channel_area_t areas[pcm->channels];
@@ -383,7 +383,7 @@ snd_pcm_plugin_readn(snd_pcm_t *pcm, void **bufs, snd_pcm_uframes_t size)
snd_pcm_plugin_read_areas);
}
-static snd_pcm_sframes_t
+snd_pcm_sframes_t
snd_pcm_plugin_mmap_commit(snd_pcm_t *pcm,
snd_pcm_uframes_t offset ATTRIBUTE_UNUSED,
snd_pcm_uframes_t size)
@@ -452,7 +452,7 @@ snd_pcm_plugin_mmap_commit(snd_pcm_t *pcm,
return xfer;
}
-static snd_pcm_sframes_t snd_pcm_plugin_avail_update(snd_pcm_t *pcm)
+snd_pcm_sframes_t snd_pcm_plugin_avail_update(snd_pcm_t *pcm)
{
snd_pcm_plugin_t *plugin = pcm->private_data;
snd_pcm_t *slave = plugin->gen.slave;
@@ -516,7 +516,7 @@ static snd_pcm_sframes_t snd_pcm_plugin_avail_update(snd_pcm_t *pcm)
}
}
-static int snd_pcm_plugin_status(snd_pcm_t *pcm, snd_pcm_status_t * status)
+int snd_pcm_plugin_status(snd_pcm_t *pcm, snd_pcm_status_t * status)
{
snd_pcm_plugin_t *plugin = pcm->private_data;
snd_pcm_sframes_t err;
diff --git a/src/pcm/pcm_plugin.h b/src/pcm/pcm_plugin.h
index 7ee7c7f..7734369 100644
--- a/src/pcm/pcm_plugin.h
+++ b/src/pcm/pcm_plugin.h
@@ -50,14 +50,42 @@ typedef struct {
} snd_pcm_plugin_t;
/* make local functions really local */
-#define snd_pcm_plugin_init \
- snd1_pcm_plugin_init
-#define snd_pcm_plugin_fast_ops \
- snd1_pcm_plugin_fast_ops
#define snd_pcm_plugin_undo_read_generic \
snd1_pcm_plugin_undo_read_generic
#define snd_pcm_plugin_undo_write_generic \
snd1_pcm_plugin_undo_write_generic
+#define snd_pcm_plugin_init \
+ snd1_pcm_plugin_init
+#define snd_pcm_plugin_delay \
+ snd1_pcm_plugin_delay
+#define snd_pcm_plugin_prepare \
+ snd1_pcm_plugin_prepare
+#define snd_pcm_plugin_reset \
+ snd1_pcm_plugin_reset
+#define snd_pcm_plugin_rewindable \
+ snd1_pcm_plugin_rewindable
+#define snd_pcm_plugin_rewind \
+ snd1_pcm_plugin_rewind
+#define snd_pcm_plugin_forwardable \
+ snd1_pcm_plugin_forwardable
+#define snd_pcm_plugin_forward \
+ snd1_pcm_plugin_forward
+#define snd_pcm_plugin_writei \
+ snd1_pcm_plugin_writei
+#define snd_pcm_plugin_writen \
+ snd1_pcm_plugin_writen
+#define snd_pcm_plugin_readi \
+ snd1_pcm_plugin_readi
+#define snd_pcm_plugin_readn \
+ snd1_pcm_plugin_readn
+#define snd_pcm_plugin_mmap_commit \
+ snd1_pcm_plugin_mmap_commit
+#define snd_pcm_plugin_avail_update \
+ snd1_pcm_plugin_avail_update
+#define snd_pcm_plugin_status \
+ snd1_pcm_plugin_status
+#define snd_pcm_plugin_fast_ops \
+ snd1_pcm_plugin_fast_ops
void snd_pcm_plugin_init(snd_pcm_plugin_t *plugin);
@@ -77,6 +105,42 @@ snd_pcm_sframes_t snd_pcm_plugin_undo_write_generic
snd_pcm_uframes_t res_size, /* size of result areas */
snd_pcm_uframes_t slave_undo_size);
+int snd_pcm_plugin_delay(snd_pcm_t *pcm, snd_pcm_sframes_t *delayp);
+int snd_pcm_plugin_prepare(snd_pcm_t *pcm);
+int snd_pcm_plugin_reset(snd_pcm_t *pcm);
+snd_pcm_sframes_t snd_pcm_plugin_rewindable(snd_pcm_t *pcm);
+snd_pcm_sframes_t snd_pcm_plugin_rewind(snd_pcm_t *pcm, snd_pcm_uframes_t frames);
+snd_pcm_sframes_t snd_pcm_plugin_forwardable(snd_pcm_t *pcm);
+snd_pcm_sframes_t snd_pcm_plugin_forward(snd_pcm_t *pcm, snd_pcm_uframes_t frames);
+
+snd_pcm_sframes_t snd_pcm_plugin_writei
+ (snd_pcm_t *pcm,
+ const void *buffer,
+ snd_pcm_uframes_t size);
+
+snd_pcm_sframes_t snd_pcm_plugin_writen
+ (snd_pcm_t *pcm,
+ void **bufs,
+ snd_pcm_uframes_t size);
+
+snd_pcm_sframes_t snd_pcm_plugin_readi
+ (snd_pcm_t *pcm,
+ void *buffer,
+ snd_pcm_uframes_t size);
+
+snd_pcm_sframes_t snd_pcm_plugin_readn
+ (snd_pcm_t *pcm,
+ void **bufs,
+ snd_pcm_uframes_t size);
+
+snd_pcm_sframes_t snd_pcm_plugin_mmap_commit
+ (snd_pcm_t *pcm,
+ snd_pcm_uframes_t offset,
+ snd_pcm_uframes_t size);
+
+snd_pcm_sframes_t snd_pcm_plugin_avail_update(snd_pcm_t *pcm);
+int snd_pcm_plugin_status(snd_pcm_t *pcm, snd_pcm_status_t * status);
+
/* make local functions really local */
#define snd_pcm_linear_get_index snd1_pcm_linear_get_index
#define snd_pcm_linear_put_index snd1_pcm_linear_put_index
--
1.9.2
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