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-rw-r--r--src/Makefile8
-rw-r--r--src/pcm.c121
-rw-r--r--src/pcm_hw.c118
-rw-r--r--src/pcm_io.h47
-rw-r--r--src/pcm_plugin.c718
-rw-r--r--src/snd_card_plugin.c149
-rw-r--r--src/snd_card_plugin.h74
7 files changed, 1195 insertions, 40 deletions
diff --git a/src/Makefile b/src/Makefile
index aa00484..b278f47 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -15,7 +15,7 @@ INCLUDE_DIRS = -I ../include
override CFLAGS := $(WARNINGS) $(INCLUDE_DIRS) -fPIC $(CFLAGS)
VPATH = ../include/tinyalsa
-OBJECTS = limits.o mixer.o pcm.o
+OBJECTS = limits.o mixer.o pcm.o pcm_plugin.o pcm_hw.o snd_card_plugin.o
LIBVERSION_MAJOR = $(TINYALSA_VERSION_MAJOR)
LIBVERSION = $(TINYALSA_VERSION)
@@ -25,10 +25,16 @@ all: libtinyalsa.a libtinyalsa.so
pcm.o: pcm.c pcm.h
+pcm_plugin.o: pcm_plugin.c pcm_io.h
+
+pcm_hw.o: pcm_hw.c pcm_io.h
+
limits.o: limits.c limits.h
mixer.o: mixer.c mixer.h
+snd_card_plugin.o: snd_card_plugin.c snd_card_plugin.h
+
libtinyalsa.a: $(OBJECTS)
$(AR) $(ARFLAGS) $@ $^
diff --git a/src/pcm.c b/src/pcm.c
index a32871e..7a8defc 100644
--- a/src/pcm.c
+++ b/src/pcm.c
@@ -59,6 +59,8 @@
#include <tinyalsa/pcm.h>
#include <tinyalsa/limits.h>
+#include "pcm_io.h"
+#include "snd_card_plugin.h"
#ifndef PARAM_MAX
#define PARAM_MAX SNDRV_PCM_HW_PARAM_LAST_INTERVAL
@@ -68,6 +70,7 @@
#define SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP (1<<2)
#endif /* SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP */
+
static inline int param_is_mask(int p)
{
return (p >= SNDRV_PCM_HW_PARAM_FIRST_MASK) &&
@@ -234,6 +237,12 @@ struct pcm {
long pcm_delay;
/** The subdevice corresponding to the PCM */
unsigned int subdevice;
+ /** Pointer to the pcm ops, either hw or plugin */
+ const struct pcm_ops *ops;
+ /** Private data for pcm_hw or pcm_plugin */
+ void *data;
+ /** Pointer to the pcm node from snd card definition */
+ struct snd_node *snd_node;
};
static int oops(struct pcm *pcm, int e, const char *fmt, ...)
@@ -383,7 +392,7 @@ int pcm_set_config(struct pcm *pcm, const struct pcm_config *config)
param_set_mask(&params, SNDRV_PCM_HW_PARAM_ACCESS,
SNDRV_PCM_ACCESS_RW_INTERLEAVED);
- if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_HW_PARAMS, &params)) {
+ if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_HW_PARAMS, &params)) {
int errno_copy = errno;
oops(pcm, -errno, "cannot set hw params");
return -errno_copy;
@@ -440,7 +449,7 @@ int pcm_set_config(struct pcm *pcm, const struct pcm_config *config)
while (pcm->boundary * 2 <= INT_MAX - pcm->buffer_size)
pcm->boundary *= 2;
- if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_SW_PARAMS, &sparams)) {
+ if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_SW_PARAMS, &sparams)) {
int errno_copy = errno;
oops(pcm, -errno, "cannot set sw params");
return -errno_copy;
@@ -519,7 +528,8 @@ static int pcm_sync_ptr(struct pcm *pcm, int flags)
}
} else {
pcm->sync_ptr->flags = flags;
- if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_SYNC_PTR, pcm->sync_ptr) < 0) {
+ if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_SYNC_PTR,
+ pcm->sync_ptr) < 0) {
oops(pcm, errno, "failed to sync mmap ptr");
return -1;
}
@@ -599,19 +609,30 @@ struct pcm_params *pcm_params_get(unsigned int card, unsigned int device,
unsigned int flags)
{
struct snd_pcm_hw_params *params;
- char fn[256];
+ void *snd_node = NULL, *data;
+ const struct pcm_ops *ops;
int fd;
- snprintf(fn, sizeof(fn), "/dev/snd/pcmC%uD%u%c", card, device,
- flags & PCM_IN ? 'c' : 'p');
-
- if (flags & PCM_NONBLOCK)
- fd = open(fn, O_RDWR | O_NONBLOCK);
- else
- fd = open(fn, O_RDWR);
+ ops = &hw_ops;
+ fd = ops->open(card, device, flags, &data, snd_node);
+#ifdef TINYALSA_USES_PLUGINS
+ if (fd < 0) {
+ int pcm_type;
+ snd_node = snd_utils_open_pcm(card, device);
+ pcm_type = snd_utils_get_node_type(snd_node);
+ if (!snd_node || pcm_type != SND_NODE_TYPE_PLUGIN) {
+ fprintf(stderr, "no device (hw/plugin) for card(%u), device(%u)",
+ card, device);
+ goto err_open;
+ }
+ ops = &plug_ops;
+ fd = ops->open(card, device, flags, &data, snd_node);
+ }
+#endif
if (fd < 0) {
- fprintf(stderr, "cannot open device '%s': %s\n", fn, strerror(errno));
+ fprintf(stderr, "cannot open card(%d) device (%d): %s\n",
+ card, device, strerror(errno));
goto err_open;
}
@@ -620,19 +641,27 @@ struct pcm_params *pcm_params_get(unsigned int card, unsigned int device,
goto err_calloc;
param_init(params);
- if (ioctl(fd, SNDRV_PCM_IOCTL_HW_REFINE, params)) {
+ if (ops->ioctl(data, SNDRV_PCM_IOCTL_HW_REFINE, params)) {
fprintf(stderr, "SNDRV_PCM_IOCTL_HW_REFINE error (%d)\n", errno);
goto err_hw_refine;
}
- close(fd);
+#ifdef TINYALSA_USES_PLUGINS
+ if (snd_node)
+ snd_utils_close_dev_node(snd_node);
+#endif
+ ops->close(data);
return (struct pcm_params *)params;
err_hw_refine:
free(params);
err_calloc:
- close(fd);
+#ifdef TINYALSA_USES_PLUGINS
+ if (snd_node)
+ snd_utils_close_dev_node(snd_node);
+#endif
+ ops->close(data);
err_open:
return NULL;
}
@@ -787,8 +816,8 @@ int pcm_close(struct pcm *pcm)
munmap(pcm->mmap_buffer, pcm_frames_to_bytes(pcm, pcm->buffer_size));
}
- if (pcm->fd >= 0)
- close(pcm->fd);
+ snd_utils_close_dev_node(pcm->snd_node);
+ pcm->ops->close(pcm->data);
pcm->buffer_size = 0;
pcm->fd = -1;
free(pcm);
@@ -851,29 +880,39 @@ struct pcm *pcm_open(unsigned int card, unsigned int device,
{
struct pcm *pcm;
struct snd_pcm_info info;
- char fn[256];
int rc;
pcm = calloc(1, sizeof(struct pcm));
if (!pcm)
return &bad_pcm;
- snprintf(fn, sizeof(fn), "/dev/snd/pcmC%uD%u%c", card, device,
- flags & PCM_IN ? 'c' : 'p');
-
- pcm->flags = flags;
-
- if (flags & PCM_NONBLOCK)
- pcm->fd = open(fn, O_RDWR | O_NONBLOCK);
- else
- pcm->fd = open(fn, O_RDWR);
+ /* Default to hw_ops, attemp plugin open only if hw (/dev/snd/pcm*) open fails */
+ pcm->ops = &hw_ops;
+ pcm->fd = pcm->ops->open(card, device, flags, &pcm->data, NULL);
+#ifdef TINYALSA_USES_PLUGINS
+ if (pcm->fd < 0) {
+ int pcm_type;
+ pcm->snd_node = snd_utils_open_pcm(card, device);
+ pcm_type = snd_utils_get_node_type(pcm->snd_node);
+ if (!pcm->snd_node || pcm_type != SND_NODE_TYPE_PLUGIN) {
+ oops(pcm, -ENODEV, "no device (hw/plugin) for card(%u), device(%u)",
+ card, device);
+ return pcm;
+ }
+ pcm->ops = &plug_ops;
+ pcm->fd = pcm->ops->open(card, device, flags, &pcm->data, pcm->snd_node);
+ }
+#endif
if (pcm->fd < 0) {
- oops(pcm, errno, "cannot open device '%s'", fn);
+ oops(pcm, errno, "cannot open device (%u) for card (%u)",
+ device, card);
return pcm;
}
- if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_INFO, &info)) {
+ pcm->flags = flags;
+
+ if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_INFO, &info)) {
oops(pcm, errno, "cannot get info");
goto fail_close;
}
@@ -891,7 +930,7 @@ struct pcm *pcm_open(unsigned int card, unsigned int device,
#ifdef SNDRV_PCM_IOCTL_TTSTAMP
if (pcm->flags & PCM_MONOTONIC) {
int arg = SNDRV_PCM_TSTAMP_TYPE_MONOTONIC;
- rc = ioctl(pcm->fd, SNDRV_PCM_IOCTL_TTSTAMP, &arg);
+ rc = pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_TTSTAMP, &arg);
if (rc < 0) {
oops(pcm, rc, "cannot set timestamp type");
goto fail;
@@ -911,7 +950,11 @@ fail:
if (flags & PCM_MMAP)
munmap(pcm->mmap_buffer, pcm_frames_to_bytes(pcm, pcm->buffer_size));
fail_close:
- close(pcm->fd);
+#ifdef TINYALSA_USES_PLUGINS
+ if (pcm->snd_node)
+ snd_utils_close_dev_node(pcm->snd_node);
+#endif
+ pcm->ops->close(pcm->data);
pcm->fd = -1;
return pcm;
}
@@ -970,7 +1013,7 @@ int pcm_unlink(struct pcm *pcm)
*/
int pcm_prepare(struct pcm *pcm)
{
- if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_PREPARE) < 0)
+ if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_PREPARE) < 0)
return oops(pcm, errno, "cannot prepare channel");
/* get appl_ptr and avail_min from kernel */
@@ -991,7 +1034,7 @@ int pcm_start(struct pcm *pcm)
return -1;
if (pcm->mmap_status->state != PCM_STATE_RUNNING) {
- if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_START) < 0)
+ if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_START) < 0)
return oops(pcm, errno, "cannot start channel");
}
@@ -1005,7 +1048,7 @@ int pcm_start(struct pcm *pcm)
*/
int pcm_stop(struct pcm *pcm)
{
- if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_DROP) < 0)
+ if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_DROP) < 0)
return oops(pcm, errno, "cannot stop channel");
return 0;
@@ -1288,7 +1331,7 @@ int pcm_mmap_transfer(struct pcm *pcm, void *buffer, unsigned int frames)
*/
if (!is_playback && state == PCM_STATE_PREPARED &&
frames >= pcm->config.start_threshold) {
- err = ioctl(pcm->fd, SNDRV_PCM_IOCTL_START);
+ err = pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_START);
if (err == -1)
return -1;
/* state = PCM_STATE_RUNNING */
@@ -1326,7 +1369,7 @@ int pcm_mmap_transfer(struct pcm *pcm, void *buffer, unsigned int frames)
/* start playback if written >= start_threshold */
if (is_playback && state == PCM_STATE_PREPARED &&
pcm->buffer_size - avail >= pcm->config.start_threshold) {
- err = ioctl(pcm->fd, SNDRV_PCM_IOCTL_START);
+ err = pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_START);
if (err == -1)
break;
}
@@ -1365,9 +1408,9 @@ static int pcm_rw_transfer(struct pcm *pcm, void *data, unsigned int frames)
transfer.frames = frames;
transfer.result = 0;
- res = ioctl(pcm->fd, is_playback
- ? SNDRV_PCM_IOCTL_WRITEI_FRAMES
- : SNDRV_PCM_IOCTL_READI_FRAMES, &transfer);
+ res = pcm->ops->ioctl(pcm->data, is_playback
+ ? SNDRV_PCM_IOCTL_WRITEI_FRAMES
+ : SNDRV_PCM_IOCTL_READI_FRAMES, &transfer);
return res == 0 ? (int) transfer.result : -1;
}
diff --git a/src/pcm_hw.c b/src/pcm_hw.c
new file mode 100644
index 0000000..1e67e9b
--- /dev/null
+++ b/src/pcm_hw.c
@@ -0,0 +1,118 @@
+/* pcm_hw.c
+** Copyright (c) 2019, The Linux Foundation.
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+** * Redistributions of source code must retain the above copyright
+** notice, this list of conditions and the following disclaimer.
+** * Redistributions in binary form must reproduce the above
+** copyright notice, this list of conditions and the following
+** disclaimer in the documentation and/or other materials provided
+** with the distribution.
+** * Neither the name of The Linux Foundation nor the names of its
+** contributors may be used to endorse or promote products derived
+** from this software without specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
+** WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+** MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
+** ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
+** BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+** BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+** WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+** OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
+** IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+**/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <fcntl.h>
+#include <stdarg.h>
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+#include <poll.h>
+
+#include <sys/ioctl.h>
+#include <linux/ioctl.h>
+#include <sound/asound.h>
+#include <tinyalsa/asoundlib.h>
+
+#include "pcm_io.h"
+
+struct pcm_hw_data {
+ /** Card number of the pcm device */
+ unsigned int card;
+ /** Device number for the pcm device */
+ unsigned int device;
+ /** File descriptor to the pcm device file node */
+ unsigned int fd;
+ /** Pointer to the pcm node from snd card definiton */
+ struct snd_node *node;
+};
+
+static void pcm_hw_close(void *data)
+{
+ struct pcm_hw_data *hw_data = data;
+
+ if (hw_data->fd > 0)
+ close(hw_data->fd);
+
+ free(hw_data);
+}
+
+static int pcm_hw_ioctl(void *data, unsigned int cmd, ...)
+{
+ struct pcm_hw_data *hw_data = data;
+ va_list ap;
+ void *arg;
+
+ va_start(ap, cmd);
+ arg = va_arg(ap, void *);
+ va_end(ap);
+
+ return ioctl(hw_data->fd, cmd, arg);
+}
+
+static int pcm_hw_open(unsigned int card, unsigned int device,
+ unsigned int flags, void **data, struct snd_node *node)
+{
+ struct pcm_hw_data *hw_data;
+ char fn[256];
+ int fd;
+
+ hw_data = calloc(1, sizeof(*hw_data));
+ if (!hw_data) {
+ return -ENOMEM;
+ }
+
+ snprintf(fn, sizeof(fn), "/dev/snd/pcmC%uD%u%c", card, device,
+ flags & PCM_IN ? 'c' : 'p');
+ if (flags & PCM_NONBLOCK)
+ fd = open(fn, O_RDWR|O_NONBLOCK);
+ else
+ fd = open(fn, O_RDWR);
+
+ if (fd < 0) {
+ return fd;
+ }
+
+ hw_data->card = card;
+ hw_data->device = device;
+ hw_data->fd = fd;
+ hw_data->node = node;
+
+ *data = hw_data;
+
+ return fd;
+}
+
+const struct pcm_ops hw_ops = {
+ .open = pcm_hw_open,
+ .close = pcm_hw_close,
+ .ioctl = pcm_hw_ioctl,
+};
+
diff --git a/src/pcm_io.h b/src/pcm_io.h
new file mode 100644
index 0000000..1b68ac8
--- /dev/null
+++ b/src/pcm_io.h
@@ -0,0 +1,47 @@
+/* pcm_io.h
+** Copyright (c) 2019, The Linux Foundation.
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+** * Redistributions of source code must retain the above copyright
+** notice, this list of conditions and the following disclaimer.
+** * Redistributions in binary form must reproduce the above
+** copyright notice, this list of conditions and the following
+** disclaimer in the documentation and/or other materials provided
+** with the distribution.
+** * Neither the name of The Linux Foundation nor the names of its
+** contributors may be used to endorse or promote products derived
+** from this software without specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
+** WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+** MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
+** ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
+** BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+** BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+** WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+** OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
+** IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+**/
+
+#ifndef TINYALSA_SRC_PCM_IO_H
+#define TINYALSA_SRC_PCM_IO_H
+
+#include <sound/asound.h>
+
+struct snd_node;
+
+struct pcm_ops {
+ int (*open) (unsigned int card, unsigned int device,
+ unsigned int flags, void **data, struct snd_node *node);
+ void (*close) (void *data);
+ int (*ioctl) (void *data, unsigned int cmd, ...);
+};
+
+extern const struct pcm_ops hw_ops;
+extern const struct pcm_ops plug_ops;
+
+#endif /* TINYALSA_SRC_PCM_IO_H */
diff --git a/src/pcm_plugin.c b/src/pcm_plugin.c
new file mode 100644
index 0000000..695ad2c
--- /dev/null
+++ b/src/pcm_plugin.c
@@ -0,0 +1,718 @@
+/* pcm_plugin.c
+** Copyright (c) 2019, The Linux Foundation.
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+** * Redistributions of source code must retain the above copyright
+** notice, this list of conditions and the following disclaimer.
+** * Redistributions in binary form must reproduce the above
+** copyright notice, this list of conditions and the following
+** disclaimer in the documentation and/or other materials provided
+** with the distribution.
+** * Neither the name of The Linux Foundation nor the names of its
+** contributors may be used to endorse or promote products derived
+** from this software without specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
+** WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+** MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
+** ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
+** BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+** BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+** WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+** OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
+** IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+**/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <fcntl.h>
+#include <stdarg.h>
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+#include <poll.h>
+#include <dlfcn.h>
+
+#include <sys/ioctl.h>
+#include <linux/ioctl.h>
+#include <sound/asound.h>
+#include <tinyalsa/asoundlib.h>
+#include <tinyalsa/plugin.h>
+
+#include "pcm_io.h"
+#include "snd_card_plugin.h"
+
+/* 2 words of uint32_t = 64 bits of mask */
+#define PCM_MASK_SIZE (2)
+#define ARRAY_SIZE(a) \
+ (sizeof(a) / sizeof(a[0]))
+
+#define PCM_PARAM_GET_MASK(p, n) \
+ &p->masks[n - SNDRV_PCM_HW_PARAM_FIRST_MASK];
+
+enum {
+ PCM_PLUG_HW_PARAM_SELECT_MIN,
+ PCM_PLUG_HW_PARAM_SELECT_MAX,
+ PCM_PLUG_HW_PARAM_SELECT_VAL,
+};
+
+enum {
+ PCM_PLUG_STATE_OPEN,
+ PCM_PLUG_STATE_SETUP,
+ PCM_PLUG_STATE_PREPARED,
+ PCM_PLUG_STATE_RUNNING,
+};
+
+struct pcm_plug_data {
+ unsigned int card;
+ unsigned int device;
+ unsigned int fd;
+ unsigned int flags;
+
+ void *dl_hdl;
+ /** pointer to plugin operation */
+ const struct pcm_plugin_ops *ops;
+ struct pcm_plugin *plugin;
+ void *dev_node;
+};
+
+static unsigned int param_list[] = {
+ SNDRV_PCM_HW_PARAM_SAMPLE_BITS,
+ SNDRV_PCM_HW_PARAM_CHANNELS,
+ SNDRV_PCM_HW_PARAM_RATE,
+ SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
+ SNDRV_PCM_HW_PARAM_PERIODS,
+};
+
+static void pcm_plug_close(void *data)
+{
+ struct pcm_plug_data *plug_data = data;
+ struct pcm_plugin *plugin = plug_data->plugin;
+
+ plug_data->ops->close(plugin);
+ dlclose(plug_data->dl_hdl);
+
+ free(plug_data);
+}
+
+static int pcm_plug_info(struct pcm_plug_data *plug_data,
+ struct snd_pcm_info *info)
+{
+ int stream = SNDRV_PCM_STREAM_PLAYBACK;
+ int ret = 0, val = -1;
+ char *name;
+
+ memset(info, 0, sizeof(*info));
+
+ if (plug_data->flags & PCM_IN) {
+ stream = SNDRV_PCM_STREAM_CAPTURE;
+ ret = snd_utils_get_int(plug_data->dev_node, "capture", &val);
+ if (ret || !val) {
+ fprintf(stderr, "%s: not a capture device\n", __func__);
+ return -EINVAL;
+ }
+ } else {
+ stream = SNDRV_PCM_STREAM_PLAYBACK;
+ ret = snd_utils_get_int(plug_data->dev_node, "playback", &val);
+ if (ret || !val) {
+ fprintf(stderr, "%s: not a playback device\n", __func__);
+ return -EINVAL;
+ }
+ }
+
+ info->stream = stream;
+ info->card = plug_data->card;
+ info->device = plug_data->device;
+
+ ret = snd_utils_get_str(plug_data->dev_node, "name", &name);
+ if (ret) {
+ fprintf(stderr, "%s: failed to get pcm device name\n", __func__);
+ return ret;
+ }
+
+ strncpy((char *)info->id, name, sizeof(info->id));
+ strncpy((char *)info->name, name, sizeof(info->name));
+ strncpy((char *)info->subname, name, sizeof(info->subname));
+
+ info->subdevices_count = 1;
+
+ return ret;
+}
+
+static void pcm_plug_set_mask(struct snd_pcm_hw_params *p, int n, uint64_t v)
+{
+ struct snd_mask *mask;
+
+ mask = PCM_PARAM_GET_MASK(p, n);
+
+ mask->bits[0] |= (v & 0xFFFFFFFF);
+ mask->bits[1] |= ((v >> 32) & 0xFFFFFFFF);
+ /*
+ * currently only supporting 64 bits, may need to update to support
+ * more than 64 bits
+ */
+}
+
+static void pcm_plug_set_interval(struct snd_pcm_hw_params *params,
+ int p, struct pcm_plugin_min_max *v, int is_integer)
+{
+ struct snd_interval *i;
+
+ i = &params->intervals[p - SNDRV_PCM_HW_PARAM_FIRST_INTERVAL];
+
+ i->min = v->min;
+ i->max = v->max;
+
+ if (is_integer)
+ i->integer = 1;
+}
+
+static int pcm_plug_frames_to_bytes(unsigned int frames,
+ unsigned int frame_bits)
+{
+ return (frames * (frame_bits / 8));
+}
+
+static int pcm_plug_bytes_to_frames(unsigned int size,
+ unsigned int frame_bits)
+{
+ return (size * 8) / frame_bits;
+}
+
+static int pcm_plug_get_params(struct pcm_plugin *plugin,
+ struct snd_pcm_hw_params *params)
+{
+ struct pcm_plugin_min_max bw, ch, pb, periods;
+ struct pcm_plugin_min_max val;
+ struct pcm_plugin_min_max frame_bits, buffer_bytes;
+
+ /*
+ * populate the struct snd_pcm_hw_params structure
+ * using the hw_param constraints provided by plugin
+ * via the plugin->constraints
+ */
+
+ /* Set the mask params */
+ pcm_plug_set_mask(params, SNDRV_PCM_HW_PARAM_ACCESS,
+ plugin->constraints->access);
+ pcm_plug_set_mask(params, SNDRV_PCM_HW_PARAM_FORMAT,
+ plugin->constraints->format);
+ pcm_plug_set_mask(params, SNDRV_PCM_HW_PARAM_SUBFORMAT,
+ SNDRV_PCM_SUBFORMAT_STD);
+
+ /* Set the standard interval params */
+ pcm_plug_set_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS,
+ &plugin->constraints->bit_width, 1);
+ pcm_plug_set_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS,
+ &plugin->constraints->channels, 1);
+ pcm_plug_set_interval(params, SNDRV_PCM_HW_PARAM_RATE,
+ &plugin->constraints->rate, 1);
+ pcm_plug_set_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
+ &plugin->constraints->period_bytes, 0);
+ pcm_plug_set_interval(params, SNDRV_PCM_HW_PARAM_PERIODS,
+ &plugin->constraints->periods, 1);
+
+ /* set the calculated interval params */
+
+ bw.min = plugin->constraints->bit_width.min;
+ bw.max = plugin->constraints->bit_width.max;
+
+ ch.min = plugin->constraints->channels.min;
+ ch.max = plugin->constraints->channels.max;
+
+ pb.min = plugin->constraints->period_bytes.min;
+ pb.max = plugin->constraints->period_bytes.max;
+
+ periods.min = plugin->constraints->periods.min;
+ periods.max = plugin->constraints->periods.max;
+
+ /* Calculate and set frame bits */
+ frame_bits.min = bw.min * ch.min;
+ frame_bits.max = bw.max * ch.max;
+ pcm_plug_set_interval(params, SNDRV_PCM_HW_PARAM_FRAME_BITS,
+ &frame_bits, 1);
+
+
+ /* Calculate and set period_size in frames */
+ val.min = pcm_plug_bytes_to_frames(pb.min, frame_bits.min);
+ val.max = pcm_plug_bytes_to_frames(pb.max, frame_bits.min);
+ pcm_plug_set_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
+ &val, 1);
+
+ /* Calculate and set buffer_bytes */
+ buffer_bytes.min = pb.min * periods.min;
+ buffer_bytes.max = pb.max * periods.max;
+ pcm_plug_set_interval(params, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
+ &buffer_bytes, 1);
+
+ /* Calculate and set buffer_size in frames */
+ val.min = pcm_plug_bytes_to_frames(buffer_bytes.min, frame_bits.min);
+ val.max = pcm_plug_bytes_to_frames(buffer_bytes.max, frame_bits.min);
+ pcm_plug_set_interval(params, SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
+ &val, 1);
+ return 0;
+}
+
+static int pcm_plug_masks_refine(struct snd_pcm_hw_params *p,
+ struct snd_pcm_hw_params *c)
+{
+ struct snd_mask *req_mask;
+ struct snd_mask *con_mask;
+ unsigned int idx, i, masks;
+
+ masks = SNDRV_PCM_HW_PARAM_LAST_MASK - SNDRV_PCM_HW_PARAM_FIRST_MASK;
+
+ for (idx = 0; idx <= masks; idx++) {
+
+ if (!(p->rmask & (1 << (idx + SNDRV_PCM_HW_PARAM_FIRST_MASK))))
+ continue;
+
+ req_mask = PCM_PARAM_GET_MASK(p, idx);
+ con_mask = PCM_PARAM_GET_MASK(c, idx);
+
+ /*
+ * set the changed mask if requested mask value is not the same as
+ * constrained mask value
+ */
+ if (memcmp(req_mask, con_mask, PCM_MASK_SIZE * sizeof(uint32_t)))
+ p->cmask |= 1 << (idx + SNDRV_PCM_HW_PARAM_FIRST_MASK);
+
+ /* Actually change the requested mask to constrained mask */
+ for (i = 0; i < PCM_MASK_SIZE; i++)
+ req_mask->bits[i] &= con_mask->bits[i];
+ }
+
+ return 0;
+}
+
+static int pcm_plug_interval_refine(struct snd_pcm_hw_params *p,
+ struct snd_pcm_hw_params *c)
+{
+ struct snd_interval *ri;
+ struct snd_interval *ci;
+ unsigned int idx;
+ unsigned int intervals;
+ int changed = 0;
+
+ intervals = SNDRV_PCM_HW_PARAM_LAST_INTERVAL -
+ SNDRV_PCM_HW_PARAM_FIRST_INTERVAL;
+
+ for (idx = 0; idx <= intervals; idx++) {
+ ri = &p->intervals[idx];
+ ci = &c->intervals[idx];
+
+ if (!(p->rmask & (1 << (idx + SNDRV_PCM_HW_PARAM_FIRST_INTERVAL)) ))
+ continue;
+
+ if (ri->min < ci->min) {
+ ri->min = ci->min;
+ ri->openmin = ci->openmin;
+ changed = 1;
+ } else if (ri->min == ci->min && !ri->openmin && ci->openmin) {
+ ri->openmin = 1;
+ changed = 1;
+ }
+
+ if (ri->max > ci->max) {
+ ri->max = ci->max;
+ ri->openmax = ci->openmax;
+ changed = 1;
+ } else if (ri->max == ci->max && !ri->openmax && ci->openmax) {
+ ri->openmax = 1;
+ changed = 1;
+ };
+
+ if (!ri->integer && ci->integer) {
+ ri->integer = 1;
+ changed = 1;
+ }
+
+ if (ri->integer) {
+ if (ri->openmin) {
+ ri->min++;
+ ri->openmin = 0;
+ }
+ if (ri->openmax) {
+ ri->max--;
+ ri->openmax = 0;
+ }
+ } else if (!ri->openmin && !ri->openmax && ri->min == ri->max) {
+ ri->integer = 1;
+ }
+
+ /* Set the changed mask */
+ if (changed)
+ p->cmask |= (1 << (idx + SNDRV_PCM_HW_PARAM_FIRST_INTERVAL));
+ }
+
+ return 0;
+}
+
+
+static int pcm_plug_hw_params_refine(struct snd_pcm_hw_params *p,
+ struct snd_pcm_hw_params *c)
+{
+ int rc;
+
+ rc = pcm_plug_masks_refine(p, c);
+ if (rc) {
+ fprintf(stderr, "%s: masks refine failed %d\n", __func__, rc);
+ return rc;
+ }
+
+ rc = pcm_plug_interval_refine(p, c);
+ if (rc) {
+ fprintf(stderr, "%s: interval refine failed %d\n", __func__, rc);
+ return rc;
+ }
+
+ /* clear the requested params */
+ p->rmask = 0;
+
+ return rc;
+}
+
+static int __pcm_plug_hrefine(struct pcm_plug_data *plug_data,
+ struct snd_pcm_hw_params *params)
+{
+ struct pcm_plugin *plugin = plug_data->plugin;
+ struct snd_pcm_hw_params plug_params;
+ int rc;
+
+ memset(&plug_params, 0, sizeof(plug_params));
+ rc = pcm_plug_get_params(plugin, &plug_params);
+ if (rc) {
+ fprintf(stderr, "%s: pcm_plug_get_params failed %d\n",
+ __func__, rc);
+ return -EINVAL;
+ }
+
+ return pcm_plug_hw_params_refine(params, &plug_params);
+
+}
+
+static int pcm_plug_hrefine(struct pcm_plug_data *plug_data,
+ struct snd_pcm_hw_params *params)
+{
+ return __pcm_plug_hrefine(plug_data, params);
+}
+
+static int pcm_plug_interval_select(struct snd_pcm_hw_params *p,
+ unsigned int param, unsigned int select, unsigned int val)
+{
+ struct snd_interval *i;
+
+ if (param < SNDRV_PCM_HW_PARAM_FIRST_INTERVAL ||
+ param > SNDRV_PCM_HW_PARAM_LAST_INTERVAL)
+ return -EINVAL;
+
+ i = &p->intervals[param - SNDRV_PCM_HW_PARAM_FIRST_INTERVAL];
+
+ if (!i->min)
+ return -EINVAL;
+
+ switch (select) {
+
+ case PCM_PLUG_HW_PARAM_SELECT_MIN:
+ i->max = i->min;
+ break;
+
+ case PCM_PLUG_HW_PARAM_SELECT_MAX:
+ i->min = i->max;
+ break;
+
+ case PCM_PLUG_HW_PARAM_SELECT_VAL:
+ i->min = i->max = val;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static void pcm_plug_hw_params_set(struct snd_pcm_hw_params *p)
+{
+ unsigned int i, select;
+ unsigned int bw, ch, period_sz, periods;
+ unsigned int val1, val2, offset;
+
+ offset = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL;
+
+ /* Select the min values first */
+ select = PCM_PLUG_HW_PARAM_SELECT_MIN;
+ for (i = 0; i < ARRAY_SIZE(param_list); i++)
+ pcm_plug_interval_select(p, param_list[i], select, 0);
+
+ /* Select calculated values */
+ select = PCM_PLUG_HW_PARAM_SELECT_VAL;
+ bw = (p->intervals[SNDRV_PCM_HW_PARAM_SAMPLE_BITS - offset]).min;
+ ch = (p->intervals[SNDRV_PCM_HW_PARAM_CHANNELS - offset]).min;
+ period_sz = (p->intervals[SNDRV_PCM_HW_PARAM_PERIOD_SIZE - offset]).min;
+ periods = (p->intervals[SNDRV_PCM_HW_PARAM_PERIODS - offset]).min;
+
+ val1 = bw * ch; // frame_bits;
+ pcm_plug_interval_select(p, SNDRV_PCM_HW_PARAM_FRAME_BITS, select, val1);
+
+ val2 = pcm_plug_frames_to_bytes(period_sz, val1); // period_bytes;
+ pcm_plug_interval_select(p, SNDRV_PCM_HW_PARAM_PERIOD_BYTES, select,
+ val2);
+
+ val2 = period_sz * periods; //buffer_size;
+ pcm_plug_interval_select(p, SNDRV_PCM_HW_PARAM_BUFFER_SIZE, select, val2);
+
+ val2 = pcm_plug_frames_to_bytes(period_sz * periods, val1); //buffer_bytes;
+ pcm_plug_interval_select(p, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, select, val2);
+}
+
+static int pcm_plug_hparams(struct pcm_plug_data *plug_data,
+ struct snd_pcm_hw_params *params)
+{
+ struct pcm_plugin *plugin = plug_data->plugin;
+ int rc;
+
+ if (plugin->state != PCM_PLUG_STATE_OPEN)
+ return -EBADFD;
+
+ params->rmask = ~0U;
+
+ rc = __pcm_plug_hrefine(plug_data, params);
+ if (rc) {
+ fprintf(stderr, "%s: __pcm_plug_hrefine failed %d\n",
+ __func__, rc);
+ return rc;
+ }
+
+ pcm_plug_hw_params_set(params);
+
+ rc = plug_data->ops->hw_params(plugin, params);
+ if (!rc)
+ plugin->state = PCM_PLUG_STATE_SETUP;
+
+ return rc;
+}
+
+static int pcm_plug_sparams(struct pcm_plug_data *plug_data,
+ struct snd_pcm_sw_params *params)
+{
+ struct pcm_plugin *plugin = plug_data->plugin;
+
+ if (plugin->state != PCM_PLUG_STATE_SETUP)
+ return -EBADFD;
+
+ return plug_data->ops->sw_params(plugin, params);
+}
+
+static int pcm_plug_sync_ptr(struct pcm_plug_data *plug_data,
+ struct snd_pcm_sync_ptr *sync_ptr)
+{
+ struct pcm_plugin *plugin = plug_data->plugin;
+
+ return plug_data->ops->sync_ptr(plugin, sync_ptr);
+}
+
+static int pcm_plug_writei_frames(struct pcm_plug_data *plug_data,
+ struct snd_xferi *x)
+{
+ struct pcm_plugin *plugin = plug_data->plugin;
+
+ if (plugin->state != PCM_PLUG_STATE_PREPARED &&
+ plugin->state != PCM_PLUG_STATE_RUNNING)
+ return -EBADFD;
+
+ return plug_data->ops->writei_frames(plugin, x);
+}
+
+static int pcm_plug_readi_frames(struct pcm_plug_data *plug_data,
+ struct snd_xferi *x)
+{
+ struct pcm_plugin *plugin = plug_data->plugin;
+
+ if (plugin->state != PCM_PLUG_STATE_RUNNING)
+ return -EBADFD;
+
+ return plug_data->ops->readi_frames(plugin, x);
+}
+
+static int pcm_plug_ttstamp(struct pcm_plug_data *plug_data,
+ int *tstamp)
+{
+ struct pcm_plugin *plugin = plug_data->plugin;
+
+ if (plugin->state != PCM_PLUG_STATE_RUNNING)
+ return -EBADFD;
+
+ return plug_data->ops->ttstamp(plugin, tstamp);
+}
+
+static int pcm_plug_prepare(struct pcm_plug_data *plug_data)
+{
+ struct pcm_plugin *plugin = plug_data->plugin;
+ int rc;
+
+ if (plugin->state != PCM_PLUG_STATE_SETUP)
+ return -EBADFD;
+
+ rc = plug_data->ops->prepare(plugin);
+ if (!rc)
+ plugin->state = PCM_PLUG_STATE_PREPARED;
+
+ return rc;
+}
+
+static int pcm_plug_start(struct pcm_plug_data *plug_data)
+{
+ struct pcm_plugin *plugin = plug_data->plugin;
+ int rc;
+
+ if (plugin->state != PCM_PLUG_STATE_PREPARED)
+ return -EBADFD;
+
+ rc = plug_data->ops->start(plugin);
+ if (!rc)
+ plugin->state = PCM_PLUG_STATE_RUNNING;
+
+ return rc;
+}
+
+static int pcm_plug_drop(struct pcm_plug_data *plug_data)
+{
+ struct pcm_plugin *plugin = plug_data->plugin;
+ int rc;
+
+ rc = plug_data->ops->drop(plugin);
+ if (!rc)
+ plugin->state = PCM_PLUG_STATE_SETUP;
+
+ return rc;
+}
+
+static int pcm_plug_ioctl(void *data, unsigned int cmd, ...)
+{
+ struct pcm_plug_data *plug_data = data;
+ struct pcm_plugin *plugin = plug_data->plugin;
+ int ret;
+ va_list ap;
+ void *arg;
+
+ va_start(ap, cmd);
+ arg = va_arg(ap, void *);
+ va_end(ap);
+
+ switch (cmd) {
+ case SNDRV_PCM_IOCTL_INFO:
+ ret = pcm_plug_info(plug_data, arg);
+ break;
+ case SNDRV_PCM_IOCTL_TTSTAMP:
+ ret = pcm_plug_ttstamp(plug_data, arg);
+ break;
+ case SNDRV_PCM_IOCTL_HW_REFINE:
+ ret = pcm_plug_hrefine(plug_data, arg);
+ break;
+ case SNDRV_PCM_IOCTL_HW_PARAMS:
+ ret = pcm_plug_hparams(plug_data, arg);
+ break;
+ case SNDRV_PCM_IOCTL_SW_PARAMS:
+ ret = pcm_plug_sparams(plug_data, arg);
+ break;
+ case SNDRV_PCM_IOCTL_SYNC_PTR:
+ ret = pcm_plug_sync_ptr(plug_data, arg);
+ break;
+ case SNDRV_PCM_IOCTL_PREPARE:
+ ret = pcm_plug_prepare(plug_data);
+ break;
+ case SNDRV_PCM_IOCTL_START:
+ ret = pcm_plug_start(plug_data);
+ break;
+ case SNDRV_PCM_IOCTL_DROP:
+ ret = pcm_plug_drop(plug_data);
+ break;
+ case SNDRV_PCM_IOCTL_WRITEI_FRAMES:
+ ret = pcm_plug_writei_frames(plug_data, arg);
+ break;
+ case SNDRV_PCM_IOCTL_READI_FRAMES:
+ ret = pcm_plug_readi_frames(plug_data, arg);
+ break;
+ default:
+ ret = plug_data->ops->ioctl(plugin, cmd, arg);
+ break;
+ }
+
+ return ret;
+}
+
+static int pcm_plug_open(unsigned int card, unsigned int device,
+ unsigned int flags, void **data, struct snd_node *pcm_node)
+{
+ struct pcm_plug_data *plug_data;
+ void *dl_hdl;
+ int rc = 0;
+ char *so_name;
+
+ plug_data = calloc(1, sizeof(*plug_data));
+ if (!plug_data) {
+ return -ENOMEM;
+ }
+
+ rc = snd_utils_get_str(pcm_node, "so-name", &so_name);
+ if (rc) {
+ fprintf(stderr, "%s: failed to get plugin lib name\n", __func__);
+ goto err_get_lib;
+ }
+
+ dl_hdl = dlopen(so_name, RTLD_NOW);
+ if (!dl_hdl) {
+ fprintf(stderr, "%s: unable to open %s\n", __func__, so_name);
+ goto err_dl_open;
+ } else {
+ fprintf(stderr, "%s: dlopen successful for %s\n", __func__, so_name);
+ }
+
+ dlerror();
+
+ plug_data->ops = dlsym(dl_hdl, "pcm_plugin_ops");
+ if (!plug_data->ops) {
+ fprintf(stderr, "%s: dlsym to open fn failed, err = '%s'\n",
+ __func__, dlerror());
+ goto err_dlsym;
+ }
+
+ rc = plug_data->ops->open(&plug_data->plugin, card, device, flags);
+ if (rc) {
+ fprintf(stderr, "%s: failed to open plugin\n", __func__);
+ goto err_open;
+ }
+
+ plug_data->dl_hdl = dl_hdl;
+ plug_data->card = card;
+ plug_data->device = device;
+ plug_data->dev_node = pcm_node;
+ plug_data->flags = flags;
+
+ *data = plug_data;
+
+ plug_data->plugin->state = PCM_PLUG_STATE_OPEN;
+
+ return 0;
+
+err_open:
+err_dlsym:
+ dlclose(dl_hdl);
+err_get_lib:
+err_dl_open:
+ free(plug_data);
+
+ return rc;
+}
+
+const struct pcm_ops plug_ops = {
+ .open = pcm_plug_open,
+ .close = pcm_plug_close,
+ .ioctl = pcm_plug_ioctl,
+};
diff --git a/src/snd_card_plugin.c b/src/snd_card_plugin.c
new file mode 100644
index 0000000..17912a2
--- /dev/null
+++ b/src/snd_card_plugin.c
@@ -0,0 +1,149 @@
+/* snd_card_plugin.c
+** Copyright (c) 2019, The Linux Foundation.
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+** * Redistributions of source code must retain the above copyright
+** notice, this list of conditions and the following disclaimer.
+** * Redistributions in binary form must reproduce the above
+** copyright notice, this list of conditions and the following
+** disclaimer in the documentation and/or other materials provided
+** with the distribution.
+** * Neither the name of The Linux Foundation nor the names of its
+** contributors may be used to endorse or promote products derived
+** from this software without specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
+** WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+** MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
+** ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
+** BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+** BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+** WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+** OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
+** IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+**/
+
+#include "snd_card_plugin.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+
+#define SND_DLSYM(h, p, s, err) \
+do { \
+ err = 0; \
+ p = dlsym(h, s); \
+ if (!p) \
+ err = -ENODEV; \
+} while(0)
+
+int snd_utils_get_int(struct snd_node *node, const char *prop, int *val)
+{
+ if (!node || !node->card_node || !node->dev_node)
+ return SND_NODE_TYPE_HW;
+
+ return node->ops->get_int(node->dev_node, prop, val);
+}
+
+int snd_utils_get_str(struct snd_node *node, const char *prop, char **val)
+{
+ if (!node || !node->card_node || !node->dev_node)
+ return SND_NODE_TYPE_HW;
+
+ return node->ops->get_str(node->dev_node, prop, val);
+}
+
+void snd_utils_close_dev_node(struct snd_node *node)
+{
+ if (!node)
+ return;
+
+ if (node->card_node)
+ node->ops->close_card(node->card_node);
+
+ if (node->dl_hdl)
+ dlclose(node->dl_hdl);
+
+ free(node);
+}
+
+enum snd_node_type snd_utils_get_node_type(struct snd_node *node)
+{
+ int val = SND_NODE_TYPE_HW;
+
+ if (!node || !node->card_node || !node->dev_node)
+ return SND_NODE_TYPE_HW;
+
+ node->ops->get_int(node->dev_node, "type", &val);
+
+ return val;
+};
+
+static int snd_utils_resolve_symbols(struct snd_node *node)
+{
+ void *dl = node->dl_hdl;
+ int err;
+ SND_DLSYM(dl, node->ops, "snd_card_ops", err);
+ return err;
+}
+
+static struct snd_node *snd_utils_open_dev_node(unsigned int card,
+ unsigned int device,
+ int dev_type)
+{
+ struct snd_node *node;
+ int rc = 0;
+
+ node = calloc(1, sizeof(*node));
+ if (!node)
+ return NULL;
+
+ node->dl_hdl = dlopen("libsndcardparser.so", RTLD_NOW);
+ if (!node->dl_hdl) {
+ goto err_dl_open;
+ }
+
+ rc = snd_utils_resolve_symbols(node);
+ if (rc < 0)
+ goto err_resolve_symbols;
+
+ node->card_node = node->ops->open_card(card);
+ if (!node->card_node)
+ goto err_resolve_symbols;
+
+ if (dev_type == NODE_PCM) {
+ node->dev_node = node->ops->get_pcm(node->card_node, device);
+ } else {
+ node->dev_node = node->ops->get_mixer(node->card_node);
+ }
+
+ if (!node->dev_node)
+ goto err_get_node;
+
+ return node;
+
+err_get_node:
+ node->ops->close_card(node->card_node);
+
+err_resolve_symbols:
+ dlclose(node->dl_hdl);
+
+err_dl_open:
+ free(node);
+ return NULL;
+}
+
+struct snd_node* snd_utils_open_pcm(unsigned int card,
+ unsigned int device)
+{
+ return snd_utils_open_dev_node(card, device, NODE_PCM);
+}
+
+struct snd_node* snd_utils_open_mixer(unsigned int card)
+{
+ return snd_utils_open_dev_node(card, 0, NODE_MIXER);
+}
diff --git a/src/snd_card_plugin.h b/src/snd_card_plugin.h
new file mode 100644
index 0000000..b80695e
--- /dev/null
+++ b/src/snd_card_plugin.h
@@ -0,0 +1,74 @@
+/* snd_utils.h
+** Copyright (c) 2019, The Linux Foundation.
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+** * Redistributions of source code must retain the above copyright
+** notice, this list of conditions and the following disclaimer.
+** * Redistributions in binary form must reproduce the above
+** copyright notice, this list of conditions and the following
+** disclaimer in the documentation and/or other materials provided
+** with the distribution.
+** * Neither the name of The Linux Foundation nor the names of its
+** contributors may be used to endorse or promote products derived
+** from this software without specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
+** WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+** MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
+** ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
+** BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+** BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+** WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+** OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
+** IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+**/
+
+#ifndef TINYALSA_SRC_SND_CARD_UTILS_H
+#define TINYALSA_SRC_SND_CARD_UTILS_H
+
+#include <tinyalsa/plugin.h>
+
+#include <dlfcn.h>
+
+/** Encapsulates the pcm device definition from
+ * the sound card definition configuration file.
+ */
+struct snd_node {
+ /** Pointer the card definition */
+ void *card_node;
+ /** Pointer to device definition, either PCM or MIXER device */
+ void *dev_node;
+ /** Pointer to the sound card parser library */
+ void *dl_hdl;
+ /** A pointer to the operations structure. */
+ const struct snd_node_ops* ops;
+};
+
+enum snd_node_type {
+ SND_NODE_TYPE_HW = 0,
+ SND_NODE_TYPE_PLUGIN,
+ SND_NODE_TYPE_INVALID,
+};
+
+enum {
+ NODE_PCM,
+ NODE_MIXER
+};
+
+struct snd_node *snd_utils_open_pcm(unsigned int card, unsigned int device);
+
+struct snd_node *snd_utils_open_mixer(unsigned int card);
+
+void snd_utils_close_dev_node(struct snd_node *node);
+
+enum snd_node_type snd_utils_get_node_type(struct snd_node *node);
+
+int snd_utils_get_int(struct snd_node *node, const char *prop, int *val);
+
+int snd_utils_get_str(struct snd_node *node, const char *prop, char **val);
+
+#endif /* end of TINYALSA_SRC_SND_CARD_UTILS_H */