Rework routing system

- Add 'route' to snd_avirt_stream, remove from audio path
- Add route checking - ensure that source ap and ink ap have
compatible hw params
- Add private data support for both source and sink Audio
Paths, to ensure that the PCM can hold multiple private data(s).
- Add ability to use copy_kernel and exttriggers from AVIRT instead of from Audio Paths
- Reintroduce pcm_trigger and pcm_prepare, so that 
they may be called appropriately from AVIRT, rather
than child Audio Paths.

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

1 files changed, 113 insertions, 40 deletions

diff --git a/configfs.c b/configfs.c
index 5668cb3..bc10efb 100644
--- a/configfs.c
+++ b/configfs.c
@@ -68,6 +68,66 @@ CFG_SND_AVIRT_CHANNELS(stream);
 CFG_SND_AVIRT_DIRECTION_RO(route);
 CFG_SND_AVIRT_CHANNELS(route);
 
+/*
+ * Check PCM hw params between a source and a sink
+ */
+#define CHK_ROUTE_ERR(source_hw, sink_hw, field)                                \
+	do {                                                                    \
+		if (source_hw->field != sink_hw->field) {                       \
+			D_ERRORK(                                               \
+				"Route HW mismatch: ##field (src:%d, sink:%d)", \
+				source_hw->field, sink_hw->field);              \
+			return -1;                                              \
+		}                                                               \
+	} while (0)
+
+/*
+ * Check the a route's source and sink Audio Path's hardware params, to ensure
+ * compatibility
+ */
+static int cfg_snd_avirt_route_verify_hw(struct snd_avirt_audiopath *source_ap,
+					 struct snd_avirt_audiopath *sink_ap)
+{
+	const struct snd_pcm_hardware *source_hw = source_ap->hw;
+	const struct snd_pcm_hardware *sink_hw = sink_ap->hw;
+
+	CHK_ROUTE_ERR(source_hw, sink_hw, channels_max);
+	CHK_ROUTE_ERR(source_hw, sink_hw, channels_min);
+	CHK_ROUTE_ERR(source_hw, sink_hw, rate_max);
+	CHK_ROUTE_ERR(source_hw, sink_hw, rate_min);
+	CHK_ROUTE_ERR(source_hw, sink_hw, rates);
+
+	return 0;
+}
+
+/*
+ * Store the Audio Path endpoint (source or sink), and check compatiblity
+ */
+static int cfg_snd_avirt_route_ap_store(struct snd_avirt_route *route,
+					struct snd_avirt_audiopath *ap,
+					snd_avirt_route_endpoint endpoint)
+{
+	/* If other endpoint is set, we want to check that the two Audio Path
+	 * endpoints are compatible before we set this endpoint */
+	if (route->endpoint_ap[!endpoint]) {
+		if (!cfg_snd_avirt_route_verify_hw(
+			    route->endpoint_ap[!endpoint], ap)) {
+			route->endpoint_ap[endpoint] = ap;
+			D_INFOK("Route successfully created: '%s' [%s -> %s]",
+				route->uid, ap->uid,
+				route->endpoint_ap[!endpoint]->uid);
+			return 0;
+		} else {
+			D_ERRORK("Route could not be created: %s", route->uid);
+			return -1;
+		}
+	} else {
+		route->endpoint_ap[endpoint] = ap;
+	}
+
+	return 0;
+}
+
 static ssize_t cfg_snd_avirt_stream_map_show(struct config_item *item,
 					     char *page)
 {
@@ -98,85 +158,100 @@ static struct configfs_attribute *cfg_snd_avirt_stream_attrs[] = {
 	NULL,
 };
 
-static ssize_t cfg_snd_avirt_route_to_ap_show(struct config_item *item,
-					      char *page)
+static ssize_t cfg_snd_avirt_route_sink_ap_show(struct config_item *item,
+						char *page)
 {
 	struct snd_avirt_route *route = snd_avirt_route_from_config_item(item);
+	if (!route) {
+		D_ERRORK("Cannot get route!");
+		goto exit_err;
+	}
 
-	if (route)
-		if (route->to_ap)
-			return sprintf(page, "%s\n", route->to_ap->uid);
+	if (route->endpoint_ap[SND_AVIRT_ROUTE_SINK])
+		return sprintf(page, "%s\n",
+			       route->endpoint_ap[SND_AVIRT_ROUTE_SINK]->uid);
 
+exit_err:
 	return sprintf(page, "\n");
 }
 
-static ssize_t cfg_snd_avirt_route_to_ap_store(struct config_item *item,
-					       const char *page, size_t count)
+static ssize_t cfg_snd_avirt_route_sink_ap_store(struct config_item *item,
+						 const char *page, size_t count)
 {
 	char *uid_ap;
 	struct snd_avirt_route *route = snd_avirt_route_from_config_item(item);
-	struct snd_avirt_audiopath *to_ap;
+	struct snd_avirt_audiopath *sink_ap;
+
+	if (!route) {
+		D_ERRORK("Cannot get route!");
+		goto exit;
+	}
 
 	uid_ap = strsep((char **)&page, "\n");
-	to_ap = snd_avirt_audiopath_get(uid_ap);
-	if (!to_ap) {
+	sink_ap = snd_avirt_audiopath_get(uid_ap);
+	if (!sink_ap) {
 		D_ERRORK("Audio Path '%s' does not exist!", uid_ap);
-		D_ERRORK("Cannot set 'route'->'to_ap'");
-		return count;
+		D_ERRORK("Cannot set 'route'->'sink_ap'");
+		goto exit;
 	}
 
-	route->to_ap = to_ap;
-	if (route->from_ap) {
-		route->from_ap->route_to_ap = to_ap;
-		route->to_ap->route_from_ap = route->from_ap;
-	}
+	cfg_snd_avirt_route_ap_store(route, sink_ap, SND_AVIRT_ROUTE_SINK);
 
+exit:
 	return count;
 }
-CONFIGFS_ATTR(cfg_snd_avirt_route_, to_ap);
+CONFIGFS_ATTR(cfg_snd_avirt_route_, sink_ap);
 
-static ssize_t cfg_snd_avirt_route_from_ap_show(struct config_item *item,
-						char *page)
+static ssize_t cfg_snd_avirt_route_source_ap_show(struct config_item *item,
+						  char *page)
 {
 	struct snd_avirt_route *route = snd_avirt_route_from_config_item(item);
+	if (!route) {
+		D_ERRORK("Cannot get route!");
+		goto exit_err;
+	}
 
-	if (route)
-		if (route->from_ap)
-			return sprintf(page, "%s\n", route->from_ap->uid);
+	if (route->endpoint_ap[SND_AVIRT_ROUTE_SOURCE])
+		return sprintf(page, "%s\n",
+			       route->endpoint_ap[SND_AVIRT_ROUTE_SOURCE]->uid);
 
+exit_err:
 	return sprintf(page, "\n");
 }
 
-static ssize_t cfg_snd_avirt_route_from_ap_store(struct config_item *item,
-						 const char *page, size_t count)
+static ssize_t cfg_snd_avirt_route_source_ap_store(struct config_item *item,
+						   const char *page,
+						   size_t count)
 {
 	char *uid_ap;
 	struct snd_avirt_route *route = snd_avirt_route_from_config_item(item);
-	struct snd_avirt_audiopath *from_ap;
+	struct snd_avirt_audiopath *source_ap;
+
+	if (!route) {
+		D_ERRORK("Cannot get route!");
+		goto exit;
+	}
 
 	uid_ap = strsep((char **)&page, "\n");
-	from_ap = snd_avirt_audiopath_get(uid_ap);
-	if (!from_ap) {
+	source_ap = snd_avirt_audiopath_get(uid_ap);
+	if (!source_ap) {
 		D_ERRORK("Audio Path '%s' does not exist!", uid_ap);
-		D_ERRORK("Cannot set 'route'->'from_ap'");
+		D_ERRORK("Cannot set 'route'->'source_ap'");
 		return count;
 	}
 
-	route->from_ap = from_ap;
-	if (route->to_ap) {
-		route->to_ap->route_from_ap = from_ap;
-		route->from_ap->route_to_ap = route->to_ap;
-	}
+	cfg_snd_avirt_route_ap_store(route, source_ap, SND_AVIRT_ROUTE_SOURCE);
 
+exit:
 	return count;
 }
-CONFIGFS_ATTR(cfg_snd_avirt_route_, from_ap);
+CONFIGFS_ATTR(cfg_snd_avirt_route_, source_ap);
 
 static struct configfs_attribute *cfg_snd_avirt_route_attrs[] = {
 	&cfg_snd_avirt_route_attr_channels,
 	&cfg_snd_avirt_route_attr_direction,
-	&cfg_snd_avirt_route_attr_from_ap,
-	&cfg_snd_avirt_route_attr_to_ap,
+	&cfg_snd_avirt_route_attr_source_ap,
+	&cfg_snd_avirt_route_attr_sink_ap,
 	NULL,
 };
 
@@ -202,7 +277,7 @@ static void cfg_snd_avirt_route_release(struct config_item *item)
 		return;
 	}
 
-	D_INFOK("Release route: %s", route->name);
+	D_INFOK("Release route: %s", route->uid);
 	kfree(route);
 }
 
@@ -297,8 +372,6 @@ cfg_snd_avirt_route_make_item(struct config_group *group, const char *name)
 	config_item_init_type_name(&route->item, name,
 				   &cfg_snd_avirt_route_type);
 
-	D_INFOK("Make route: %s", route->name);
-
 	return &route->item;
 }