Add support for routes

Signed-off-by: Mark Farrugia <mark.farrugia@fiberdyne.com.au>

2 files changed, 210 insertions, 39 deletions

diff --git a/include/avirt/avirt.h b/include/avirt/avirt.h
index f1c4060..1ebed32 100644
--- a/include/avirt/avirt.h
+++ b/include/avirt/avirt.h
@@ -23,7 +23,46 @@
 #ifndef _AVIRT_H_
 #define _AVIRT_H_
 
+#define MAX_STREAMS 16
+#define MAX_NAME_LEN 80
+
 #include <alsa/asoundlib.h>
+#include <stdbool.h>
+
+/**
+ * AVIRT Audio Path info
+ */
+typedef struct snd_avirt_audiopath snd_avirt_audiopath;
+struct snd_avirt_audiopath {
+  const char *uid; /* Unique identifier */
+  const char *name; /* Pretty name */
+  unsigned int version[3]; /* Version - Major.Minor.Ext */
+
+  // MUST be at the end
+  struct snd_avirt_audiopath *route_from_ap;
+  struct snd_avirt_audiopath *route_to_ap;
+};
+
+/*
+ * Audio stream configuration
+ */
+struct snd_avirt_stream {
+  const char name[MAX_NAME_LEN]; /* Stream name */
+  const char map[MAX_NAME_LEN]; /* Stream Audio Path mapping */
+  unsigned int channels; /* Stream channel count */
+  unsigned int direction; /* Stream direction */
+};
+
+/**
+ * Audio routing
+ */
+struct snd_avirt_route {
+  const char name[MAX_NAME_LEN]; /* Route name */
+  unsigned int channels; /* Route channel count */
+  unsigned int direction; /* Stream direction */
+  struct snd_avirt_audiopath *from_ap;
+  struct snd_avirt_audiopath *to_ap;
+};
 
 /**
  * snd_avirt_stream_new - Create a stream in AVIRT
@@ -32,6 +71,7 @@
  * @direction: The stream direction
  *             (SND_PCM_STREAM_PLAYBACK or SND_PCM_STREAM_CAPTURE)
  * @map: The audio path to map this stream to
+ * @internal: Make the PCM internal.
  * @return: 0 on success, negative ERRNO otherwise
  *
  * Each stream creates a PCM device for the AVIRT sound card.
@@ -39,7 +79,29 @@
  * is called.
  */
 int snd_avirt_stream_new(const char *name, unsigned int channels, int direction,
-                         const char *map);
+                         const char *map, bool internal);
+
+/**
+ * snd_avirt_route_new - Create a route between Audio Paths in AVIRT
+ * @name: The name of the route.
+ * @channels: Number of channels for the route
+ * @direction: The route stream direction
+ *             (SND_PCM_STREAM_PLAYBACK or SND_PCM_STREAM_CAPTURE)
+ * @from_ap: The Audio Path UID to route audio from
+ * @to_ap: The Audio Path UID to route audio to
+ * @return: 0 on success, negative ERRNO otherwise
+ *
+ * Allows Audio Paths to be piped together to allow for modular processing
+ * and/or networking. The "to" Audio Path must be able to accept a stream
+ * input whose channel count equals to "from" Audio Path's output channel
+ * count.
+ */
+int snd_avirt_route_new(const char *name, int channels, int direction,
+                        const char *from_ap, const char *to_ap);
+
+int snd_avirt_routes(struct snd_avirt_route **routes, int *count);
+int snd_avirt_streams(struct snd_avirt_stream **streams, int *count);
+int snd_avirt_audiopaths(struct snd_avirt_audiopath **audiopaths, int *count);
 
 /**
  * snd_avirt_card_seal - Finalize AVIRT stream creation and register sound card
diff --git a/src/avirt-config.c b/src/avirt-config.c
index 0f92540..267c727 100644
--- a/src/avirt-config.c
+++ b/src/avirt-config.c
@@ -29,8 +29,12 @@
 #include <sys/mount.h>
 
 #define AVIRT_CONFIGFS_PATH_STREAMS "/config/snd-avirt/streams/"
-#define AVIRT_CONFIGFS_PATH_MAXLEN 64
-#define AVIRT_DEVICE_PATH "/dev/snd/by-path/platform-snd_avirt"
+#define AVIRT_CONFIGFS_PATH_ROUTES  "/config/snd-avirt/routes/"
+#define AVIRT_SYSFS_PATH_AUDIOPATHS "/sys/class/snd_avirt/core/audiopaths/"
+#define AVIRT_DEVICE_PATH           "/dev/snd/by-path/platform-snd_avirt"
+
+#define AVIRT_CONFIGFS_PATH_MAXLEN  64
+#define AVIRT_SYSFS_PATH_MAXLEN     80
 
 /**
  * Logging macros
@@ -141,6 +145,32 @@ static int mount_configfs()
   return err;
 }
 
+static int audiopath_exists(const char *uid)
+{
+  DIR *dir;
+  char path[AVIRT_SYSFS_PATH_MAXLEN];
+
+  // Check that the Audio Paths exist
+  strcpy(path, AVIRT_SYSFS_PATH_AUDIOPATHS);
+  strcat(path, uid);
+  dir = opendir(path);
+  if (dir)
+  {
+    closedir(dir);
+    return 0;
+  }
+  else if (errno == ENOENT)
+  {
+    AVIRT_ERROR_V("Audio Path '%s' does not exist", uid);
+  }
+  else
+  {
+    AVIRT_ERROR("Could not check for Audio Path existence");
+  }
+
+  return -errno;
+}
+
 static int find_mixer_selem(const char *name, snd_mixer_t **handle,
                             snd_mixer_elem_t **selem)
 {
@@ -178,6 +208,52 @@ close_handle:
   return retval;
 }
 
+static int snd_avirt_configfs_item_new(const char *name,
+                                       unsigned int direction,
+                                       char *path, bool internal)
+{
+  int err;
+
+  IS_CONFIGFS_MOUNTED();
+
+  // Check if card is already sealed
+  if (card_sealed)
+  {
+    AVIRT_ERROR("Card is already sealed!");
+    return -EPERM;
+  }
+
+  // This indicates to AVIRT the direction of the item
+  switch (direction) {
+    case SND_PCM_STREAM_PLAYBACK:
+      strcat(path, "playback_");
+      break;
+    case SND_PCM_STREAM_CAPTURE:
+      strcat(path, "capture_");
+      break;
+    default:
+      return -EINVAL;
+  }
+
+  if ((AVIRT_CONFIGFS_PATH_MAXLEN - strlen(path)) < strlen(name))
+  {
+    AVIRT_ERROR_V("Cannot create config item '%s' since name is too long!", name);
+    return -ENOMEM;
+  }
+
+  strcat(path, name);
+  if (internal)
+    strcat(path, "__internal");
+  err = mkdir(path, S_IRWXU | S_IRWXG | S_IRWXO);
+  if (err < 0)
+  {
+    AVIRT_ERROR_V("Cannot create config item '%s' at directory '%s'", name, path);
+    return err;
+  }
+
+  return 0;
+}
+
 int snd_avirt_card_index_get(int idx)
 {
   int open_dev, err = 0;
@@ -303,9 +379,8 @@ close_handle:
 }
 
 int snd_avirt_stream_new(const char *name, unsigned int channels, int direction,
-                         const char *map)
+                         const char *map, bool internal)
 {
-  int err;
   char path[AVIRT_CONFIGFS_PATH_MAXLEN];
   char path_attr[AVIRT_CONFIGFS_PATH_MAXLEN];
 
@@ -315,41 +390,8 @@ int snd_avirt_stream_new(const char *name, unsigned int channels, int direction,
     return -ERANGE;
   }
 
-  IS_CONFIGFS_MOUNTED();
-
-  // Check if card is already sealed
-  if (card_sealed)
-  {
-    AVIRT_ERROR("Card is already sealed!");
-    return -EPERM;
-  }
-
-  // This indicates to AVIRT the direction of the stream
   strcpy(path, AVIRT_CONFIGFS_PATH_STREAMS);
-  switch (direction) {
-    case SND_PCM_STREAM_PLAYBACK:
-      strcat(path, "playback_");
-      break;
-    case SND_PCM_STREAM_CAPTURE:
-      strcat(path, "capture_");
-      break;
-    default:
-      return -EINVAL;
-  }
-
-  if ((AVIRT_CONFIGFS_PATH_MAXLEN - strlen(path)) < strlen(name))
-  {
-    AVIRT_ERROR_V("Cannot create stream '%s' since name is too long!", name);
-    return -ENOMEM;
-  }
-
-  strcat(path, name);
-  err = mkdir(path, S_IRWXU | S_IRWXG | S_IRWXO);
-  if (err < 0)
-  {
-    AVIRT_ERROR_V("Cannot create stream '%s' at directory '%s'", name, path);
-    return err;
-  }
+  CHK_ERR(snd_avirt_configfs_item_new(name, direction, path, internal), "");
 
   // Write channels
   strcpy(path_attr, path);
@@ -359,6 +401,7 @@ int snd_avirt_stream_new(const char *name, unsigned int channels, int direction,
   if (map)
   {
     // Write mapping
+    memset(path_attr, 0, AVIRT_CONFIGFS_PATH_MAXLEN);
     strcpy(path_attr, path);
     strcat(path_attr, "/map");
     WRITE_TO_PATH(path_attr, "%s", map);
@@ -373,9 +416,64 @@ int snd_avirt_stream_new(const char *name, unsigned int channels, int direction,
   return 0;
 }
 
+int snd_avirt_route_new(const char *name, int channels, int direction,
+                        const char *source_ap, const char *sink_ap)
+{
+  int err;
+  char path[AVIRT_CONFIGFS_PATH_MAXLEN];
+  char path_attr[AVIRT_CONFIGFS_PATH_MAXLEN];
+
+  if ((channels > __INT_MAX__) || (channels == 0))
+  {
+    AVIRT_ERROR_V("Channels '%d' is out of range!", channels);
+    return -ERANGE;
+  }
+
+  // Check that the Audio Paths exist
+  err = audiopath_exists(source_ap);
+  if (err < 0)
+    return err;
+  err = audiopath_exists(sink_ap);
+  if (err < 0)
+    return err;
+
+  strcpy(path, AVIRT_CONFIGFS_PATH_ROUTES);
+  CHK_ERR(snd_avirt_configfs_item_new(name, direction, path, false), "");
+
+  // Write channels
+  strcpy(path_attr, path);
+  strcat(path_attr, "/channels");
+  WRITE_TO_PATH(path_attr, "%d", channels);
+
+  // Write route_sink_ap into route_source_ap's 'to' path
+  memset(path_attr, 0, AVIRT_CONFIGFS_PATH_MAXLEN);
+  strcpy(path_attr, path);
+  strcat(path_attr, "/sink_ap");
+  WRITE_TO_PATH(path_attr, sink_ap);
+
+  // Write route_source_ap into route_sink_ap's 'from' path
+  memset(path_attr, 0, AVIRT_CONFIGFS_PATH_MAXLEN);
+  strcpy(path_attr, path);
+  strcat(path_attr, "/source_ap");
+  WRITE_TO_PATH(path_attr, source_ap);
+
+  CHK_ERR(snd_avirt_stream_new(name, channels, !direction, source_ap, true),
+          "Couldn't create stream: %s", name);
+
+  CHK_ERR(snd_avirt_stream_new(name, channels, direction, sink_ap, false),
+          "Couldn't create stream: %s", name);
+
+  AVIRT_DEBUG_V("Created route: %s -> %s", source_ap, sink_ap);
+
+  return 0;
+}
+
 int snd_avirt_card_seal()
 {
+  char cmd[128];
   char path_sealed[AVIRT_CONFIGFS_PATH_MAXLEN];
+  snd_pcm_info_t *route_pcm_info;
+  int err = 0;
 
   // Check if card is already sealed
   if (card_sealed)
@@ -398,8 +496,19 @@ int snd_avirt_card_seal()
   if (card_index < 0)
     return card_index;
 
+  // TD MF: HACK: Open the UNICENS device
+  snd_pcm_info_alloca(&route_pcm_info);
+  snd_avirt_pcm_info("ep01-6ch", route_pcm_info);
+
+  sprintf(cmd, "speaker-test -Dhw:%d,%d -c6 >/dev/null &",
+         card_index, snd_pcm_info_get_device(route_pcm_info));
+  AVIRT_DEBUG_V("Running router: '%s'", cmd);
+  err = system(cmd);
 
 
+  return 0;
+}
+
 
   return 0;
 }