ASoC: dapm: Consolidate input and output path handling

After the recent cleanups and generalizations of the DAPM algorithm the
handling of input and output paths is now fully symmetric. This means by
making some slight changes to the data structure and using arrays with one
entry for each direction, rather than separate fields, it is possible to
create a generic implementation that is capable of handling both input and
output paths.

Unfortunately this generalization significantly increases the code size on
the hot path of is_connected_{input,output}_ep() and
dapm_widget_invalidate_{input,output}_paths(), which has a negative impact
on the overall performance. The inner loops of those functions are quite
small and the generic implementation adds extra pointer arithmetic in a few
places.

Testing on ARM shows that the combined code size of the specialized
functions is about 50% larger than the generalized function in relative
numbers. But in absolute numbers its less than 200 bytes, which is still
quite small. On the other hand the generalized function increases the
execution time of dapm_power_one_widget() by 30%. Given that this function
is one of the most often called functions of the DAPM framework the
trade-off of getting better performance at expense of generating slightly
larger code at seems to be worth it.

To avoid this still keep two versions of these functions around, one for
input and one for output. But have a generic implementation of the
algorithm which gets inlined by those two versions. And then let the
compiler take care of optimizing it and removing he extra instructions.

This still reduces the source code size as well as the makes making changes
to the implementation more straight forward since the same change does no
longer need to be done in two separate places. Also on the slow paths we
can use a generic implementations that handle both input and output paths.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c
index fa09108..27b7fd9 100644
--- a/sound/soc/soc-dapm.c
+++ b/sound/soc/soc-dapm.c
@@ -47,6 +47,13 @@
 
 #define DAPM_UPDATE_STAT(widget, val) widget->dapm->card->dapm_stats.val++;
 
+#define SND_SOC_DAPM_DIR_REVERSE(x) ((x == SND_SOC_DAPM_DIR_IN) ? \
+	SND_SOC_DAPM_DIR_OUT : SND_SOC_DAPM_DIR_IN)
+
+#define snd_soc_dapm_for_each_direction(dir) \
+	for ((dir) = SND_SOC_DAPM_DIR_IN; (dir) <= SND_SOC_DAPM_DIR_OUT; \
+		(dir)++)
+
 static int snd_soc_dapm_add_path(struct snd_soc_dapm_context *dapm,
 	struct snd_soc_dapm_widget *wsource, struct snd_soc_dapm_widget *wsink,
 	const char *control,
@@ -167,45 +174,59 @@
 }
 
 /*
- * dapm_widget_invalidate_input_paths() - Invalidate the cached number of input
- *  paths
- * @w: The widget for which to invalidate the cached number of input paths
- *
- * The function resets the cached number of inputs for the specified widget and
- * all widgets that can be reached via outgoing paths from the widget.
- *
- * This function must be called if the number of input paths for a widget might
- * have changed. E.g. if the source state of a widget changes or a path is added
- * or activated with the widget as the sink.
+ * Common implementation for dapm_widget_invalidate_input_paths() and
+ * dapm_widget_invalidate_output_paths(). The function is inlined since the
+ * combined size of the two specialized functions is only marginally larger then
+ * the size of the generic function and at the same time the fast path of the
+ * specialized functions is significantly smaller than the generic function.
  */
-static void dapm_widget_invalidate_input_paths(struct snd_soc_dapm_widget *w)
+static __always_inline void dapm_widget_invalidate_paths(
+	struct snd_soc_dapm_widget *w, enum snd_soc_dapm_direction dir)
 {
-	struct snd_soc_dapm_widget *sink;
+	enum snd_soc_dapm_direction rdir = SND_SOC_DAPM_DIR_REVERSE(dir);
+	struct snd_soc_dapm_widget *node;
 	struct snd_soc_dapm_path *p;
 	LIST_HEAD(list);
 
 	dapm_assert_locked(w->dapm);
 
-	if (w->inputs == -1)
+	if (w->endpoints[dir] == -1)
 		return;
 
-	w->inputs = -1;
 	list_add_tail(&w->work_list, &list);
+	w->endpoints[dir] = -1;
 
 	list_for_each_entry(w, &list, work_list) {
-		snd_soc_dapm_widget_for_each_sink_path(w, p) {
+		snd_soc_dapm_widget_for_each_path(w, dir, p) {
 			if (p->is_supply || p->weak || !p->connect)
 				continue;
-			sink = p->sink;
-			if (sink->inputs != -1) {
-				sink->inputs = -1;
-				list_add_tail(&sink->work_list, &list);
+			node = p->node[rdir];
+			if (node->endpoints[dir] != -1) {
+				node->endpoints[dir] = -1;
+				list_add_tail(&node->work_list, &list);
 			}
 		}
 	}
 }
 
 /*
+ * dapm_widget_invalidate_input_paths() - Invalidate the cached number of
+ *  input paths
+ * @w: The widget for which to invalidate the cached number of input paths
+ *
+ * Resets the cached number of inputs for the specified widget and all widgets
+ * that can be reached via outcoming paths from the widget.
+ *
+ * This function must be called if the number of output paths for a widget might
+ * have changed. E.g. if the source state of a widget changes or a path is added
+ * or activated with the widget as the sink.
+ */
+static void dapm_widget_invalidate_input_paths(struct snd_soc_dapm_widget *w)
+{
+	dapm_widget_invalidate_paths(w, SND_SOC_DAPM_DIR_IN);
+}
+
+/*
  * dapm_widget_invalidate_output_paths() - Invalidate the cached number of
  *  output paths
  * @w: The widget for which to invalidate the cached number of output paths
@@ -219,29 +240,7 @@
  */
 static void dapm_widget_invalidate_output_paths(struct snd_soc_dapm_widget *w)
 {
-	struct snd_soc_dapm_widget *source;
-	struct snd_soc_dapm_path *p;
-	LIST_HEAD(list);
-
-	dapm_assert_locked(w->dapm);
-
-	if (w->outputs == -1)
-		return;
-
-	w->outputs = -1;
-	list_add_tail(&w->work_list, &list);
-
-	list_for_each_entry(w, &list, work_list) {
-		snd_soc_dapm_widget_for_each_source_path(w, p) {
-			if (p->is_supply || p->weak || !p->connect)
-				continue;
-			source = p->source;
-			if (source->outputs != -1) {
-				source->outputs = -1;
-				list_add_tail(&source->work_list, &list);
-			}
-		}
-	}
+	dapm_widget_invalidate_paths(w, SND_SOC_DAPM_DIR_OUT);
 }
 
 /*
@@ -270,9 +269,9 @@
 	 * endpoints is either connected or disconnected that sum won't change,
 	 * so there is no need to re-check the path.
 	 */
-	if (p->source->inputs != 0)
+	if (p->source->endpoints[SND_SOC_DAPM_DIR_IN] != 0)
 		dapm_widget_invalidate_input_paths(p->sink);
-	if (p->sink->outputs != 0)
+	if (p->sink->endpoints[SND_SOC_DAPM_DIR_OUT] != 0)
 		dapm_widget_invalidate_output_paths(p->source);
 }
 
@@ -283,11 +282,11 @@
 	mutex_lock(&card->dapm_mutex);
 
 	list_for_each_entry(w, &card->widgets, list) {
-		if (w->is_sink || w->is_source) {
+		if (w->is_ep) {
 			dapm_mark_dirty(w, "Rechecking endpoints");
-			if (w->is_sink)
+			if (w->is_ep & SND_SOC_DAPM_EP_SINK)
 				dapm_widget_invalidate_output_paths(w);
-			if (w->is_source)
+			if (w->is_ep & SND_SOC_DAPM_EP_SOURCE)
 				dapm_widget_invalidate_input_paths(w);
 		}
 	}
@@ -923,18 +922,18 @@
 static int dapm_new_mux(struct snd_soc_dapm_widget *w)
 {
 	struct snd_soc_dapm_context *dapm = w->dapm;
+	enum snd_soc_dapm_direction dir;
 	struct snd_soc_dapm_path *path;
-	struct list_head *paths;
 	const char *type;
 	int ret;
 
 	switch (w->id) {
 	case snd_soc_dapm_mux:
-		paths = &w->sources;
+		dir = SND_SOC_DAPM_DIR_OUT;
 		type = "mux";
 		break;
 	case snd_soc_dapm_demux:
-		paths = &w->sinks;
+		dir = SND_SOC_DAPM_DIR_IN;
 		type = "demux";
 		break;
 	default:
@@ -948,7 +947,7 @@
 		return -EINVAL;
 	}
 
-	if (list_empty(paths)) {
+	if (list_empty(&w->edges[dir])) {
 		dev_err(dapm->dev, "ASoC: %s %s has no paths\n", type, w->name);
 		return -EINVAL;
 	}
@@ -957,16 +956,9 @@
 	if (ret < 0)
 		return ret;
 
-	if (w->id == snd_soc_dapm_mux) {
-		snd_soc_dapm_widget_for_each_source_path(w, path) {
-			if (path->name)
-				dapm_kcontrol_add_path(w->kcontrols[0], path);
-		}
-	} else {
-		snd_soc_dapm_widget_for_each_sink_path(w, path) {
-			if (path->name)
-				dapm_kcontrol_add_path(w->kcontrols[0], path);
-		}
+	snd_soc_dapm_widget_for_each_path(w, dir, path) {
+		if (path->name)
+			dapm_kcontrol_add_path(w->kcontrols[0], path);
 	}
 
 	return 0;
@@ -1055,18 +1047,32 @@
 	return 0;
 }
 
-/*
- * Recursively check for a completed path to an active or physically connected
- * output widget. Returns number of complete paths.
- */
-static int is_connected_output_ep(struct snd_soc_dapm_widget *widget,
-	struct list_head *list)
+static void trace_snd_soc_dapm_path(struct snd_soc_dapm_widget *w,
+	enum snd_soc_dapm_direction dir, struct snd_soc_dapm_path *p)
 {
+	if (dir == SND_SOC_DAPM_DIR_IN)
+		trace_snd_soc_dapm_input_path(w, p);
+	else
+		trace_snd_soc_dapm_output_path(w, p);
+}
+
+/*
+ * Common implementation for is_connected_output_ep() and
+ * is_connected_input_ep(). The function is inlined since the combined size of
+ * the two specialized functions is only marginally larger then the size of the
+ * generic function and at the same time the fast path of the specialized
+ * functions is significantly smaller than the generic function.
+ */
+static __always_inline int is_connected_ep(struct snd_soc_dapm_widget *widget,
+	struct list_head *list, enum snd_soc_dapm_direction dir,
+	int (*fn)(struct snd_soc_dapm_widget *, struct list_head *))
+{
+	enum snd_soc_dapm_direction rdir = SND_SOC_DAPM_DIR_REVERSE(dir);
 	struct snd_soc_dapm_path *path;
 	int con = 0;
 
-	if (widget->outputs >= 0)
-		return widget->outputs;
+	if (widget->endpoints[dir] >= 0)
+		return widget->endpoints[dir];
 
 	DAPM_UPDATE_STAT(widget, path_checks);
 
@@ -1074,12 +1080,12 @@
 	if (list)
 		list_add_tail(&widget->work_list, list);
 
-	if (widget->is_sink && widget->connected) {
-		widget->outputs = snd_soc_dapm_suspend_check(widget);
-		return widget->outputs;
+	if ((widget->is_ep & SND_SOC_DAPM_DIR_TO_EP(dir)) && widget->connected) {
+		widget->endpoints[dir] = snd_soc_dapm_suspend_check(widget);
+		return widget->endpoints[dir];
 	}
 
-	snd_soc_dapm_widget_for_each_sink_path(widget, path) {
+	snd_soc_dapm_widget_for_each_path(widget, rdir, path) {
 		DAPM_UPDATE_STAT(widget, neighbour_checks);
 
 		if (path->weak || path->is_supply)
@@ -1088,65 +1094,40 @@
 		if (path->walking)
 			return 1;
 
-		trace_snd_soc_dapm_output_path(widget, path);
+		trace_snd_soc_dapm_path(widget, dir, path);
 
 		if (path->connect) {
 			path->walking = 1;
-			con += is_connected_output_ep(path->sink, list);
+			con += fn(path->node[dir], list);
 			path->walking = 0;
 		}
 	}
 
-	widget->outputs = con;
+	widget->endpoints[dir] = con;
 
 	return con;
 }
 
 /*
  * Recursively check for a completed path to an active or physically connected
+ * output widget. Returns number of complete paths.
+ */
+static int is_connected_output_ep(struct snd_soc_dapm_widget *widget,
+	struct list_head *list)
+{
+	return is_connected_ep(widget, list, SND_SOC_DAPM_DIR_OUT,
+			is_connected_output_ep);
+}
+
+/*
+ * Recursively check for a completed path to an active or physically connected
  * input widget. Returns number of complete paths.
  */
 static int is_connected_input_ep(struct snd_soc_dapm_widget *widget,
 	struct list_head *list)
 {
-	struct snd_soc_dapm_path *path;
-	int con = 0;
-
-	if (widget->inputs >= 0)
-		return widget->inputs;
-
-	DAPM_UPDATE_STAT(widget, path_checks);
-
-	/* do we need to add this widget to the list ? */
-	if (list)
-		list_add_tail(&widget->work_list, list);
-
-	if (widget->is_source && widget->connected) {
-		widget->inputs = snd_soc_dapm_suspend_check(widget);
-		return widget->inputs;
-	}
-
-	snd_soc_dapm_widget_for_each_source_path(widget, path) {
-		DAPM_UPDATE_STAT(widget, neighbour_checks);
-
-		if (path->weak || path->is_supply)
-			continue;
-
-		if (path->walking)
-			return 1;
-
-		trace_snd_soc_dapm_input_path(widget, path);
-
-		if (path->connect) {
-			path->walking = 1;
-			con += is_connected_input_ep(path->source, list);
-			path->walking = 0;
-		}
-	}
-
-	widget->inputs = con;
-
-	return con;
+	return is_connected_ep(widget, list, SND_SOC_DAPM_DIR_IN,
+			is_connected_input_ep);
 }
 
 /**
@@ -1177,8 +1158,8 @@
 	 * to reset the cached number of inputs and outputs.
 	 */
 	list_for_each_entry(w, &card->widgets, list) {
-		w->inputs = -1;
-		w->outputs = -1;
+		w->endpoints[SND_SOC_DAPM_DIR_IN] = -1;
+		w->endpoints[SND_SOC_DAPM_DIR_OUT] = -1;
 	}
 
 	if (stream == SNDRV_PCM_STREAM_PLAYBACK)
@@ -1922,6 +1903,7 @@
 {
 	struct snd_soc_dapm_widget *w = file->private_data;
 	struct snd_soc_card *card = w->dapm->card;
+	enum snd_soc_dapm_direction dir, rdir;
 	char *buf;
 	int in, out;
 	ssize_t ret;
@@ -1958,25 +1940,21 @@
 				w->sname,
 				w->active ? "active" : "inactive");
 
-	snd_soc_dapm_widget_for_each_source_path(w, p) {
-		if (p->connected && !p->connected(w, p->source))
-			continue;
+	snd_soc_dapm_for_each_direction(dir) {
+		rdir = SND_SOC_DAPM_DIR_REVERSE(dir);
+		snd_soc_dapm_widget_for_each_path(w, dir, p) {
+			if (p->connected && !p->connected(w, p->node[rdir]))
+				continue;
 
-		if (p->connect)
-			ret += snprintf(buf + ret, PAGE_SIZE - ret,
-					" in  \"%s\" \"%s\"\n",
-					p->name ? p->name : "static",
-					p->source->name);
-	}
-	snd_soc_dapm_widget_for_each_sink_path(w, p) {
-		if (p->connected && !p->connected(w, p->sink))
-			continue;
+			if (!p->connect)
+				continue;
 
-		if (p->connect)
 			ret += snprintf(buf + ret, PAGE_SIZE - ret,
-					" out \"%s\" \"%s\"\n",
+					" %s  \"%s\" \"%s\"\n",
+					(rdir == SND_SOC_DAPM_DIR_IN) ? "in" : "out",
 					p->name ? p->name : "static",
-					p->sink->name);
+					p->node[rdir]->name);
+		}
 	}
 
 	mutex_unlock(&card->dapm_mutex);
@@ -2276,8 +2254,8 @@
 
 static void dapm_free_path(struct snd_soc_dapm_path *path)
 {
-	list_del(&path->list_sink);
-	list_del(&path->list_source);
+	list_del(&path->list_node[SND_SOC_DAPM_DIR_IN]);
+	list_del(&path->list_node[SND_SOC_DAPM_DIR_OUT]);
 	list_del(&path->list_kcontrol);
 	list_del(&path->list);
 	kfree(path);
@@ -2286,6 +2264,7 @@
 void snd_soc_dapm_free_widget(struct snd_soc_dapm_widget *w)
 {
 	struct snd_soc_dapm_path *p, *next_p;
+	enum snd_soc_dapm_direction dir;
 
 	list_del(&w->list);
 	/*
@@ -2293,11 +2272,10 @@
 	 * While removing the path, remove reference to it from both
 	 * source and sink widgets so that path is removed only once.
 	 */
-	list_for_each_entry_safe(p, next_p, &w->sources, list_sink)
-		dapm_free_path(p);
-
-	list_for_each_entry_safe(p, next_p, &w->sinks, list_source)
-		dapm_free_path(p);
+	snd_soc_dapm_for_each_direction(dir) {
+		snd_soc_dapm_widget_for_each_path_safe(w, dir, p, next_p)
+			dapm_free_path(p);
+	}
 
 	kfree(w->kcontrols);
 	kfree_const(w->name);
@@ -2418,20 +2396,22 @@
  */
 static void dapm_update_widget_flags(struct snd_soc_dapm_widget *w)
 {
+	enum snd_soc_dapm_direction dir;
 	struct snd_soc_dapm_path *p;
+	unsigned int ep;
 
 	switch (w->id) {
 	case snd_soc_dapm_input:
 		/* On a fully routed card a input is never a source */
 		if (w->dapm->card->fully_routed)
-			break;
-		w->is_source = 1;
+			return;
+		ep = SND_SOC_DAPM_EP_SOURCE;
 		snd_soc_dapm_widget_for_each_source_path(w, p) {
 			if (p->source->id == snd_soc_dapm_micbias ||
 				p->source->id == snd_soc_dapm_mic ||
 				p->source->id == snd_soc_dapm_line ||
 				p->source->id == snd_soc_dapm_output) {
-					w->is_source = 0;
+					ep = 0;
 					break;
 			}
 		}
@@ -2439,25 +2419,30 @@
 	case snd_soc_dapm_output:
 		/* On a fully routed card a output is never a sink */
 		if (w->dapm->card->fully_routed)
-			break;
-		w->is_sink = 1;
+			return;
+		ep = SND_SOC_DAPM_EP_SINK;
 		snd_soc_dapm_widget_for_each_sink_path(w, p) {
 			if (p->sink->id == snd_soc_dapm_spk ||
 				p->sink->id == snd_soc_dapm_hp ||
 				p->sink->id == snd_soc_dapm_line ||
 				p->sink->id == snd_soc_dapm_input) {
-					w->is_sink = 0;
+					ep = 0;
 					break;
 			}
 		}
 		break;
 	case snd_soc_dapm_line:
-		w->is_sink = !list_empty(&w->sources);
-		w->is_source = !list_empty(&w->sinks);
+		ep = 0;
+		snd_soc_dapm_for_each_direction(dir) {
+			if (!list_empty(&w->edges[dir]))
+				ep |= SND_SOC_DAPM_DIR_TO_EP(dir);
+		}
 		break;
 	default:
-		break;
+		return;
 	}
+
+	w->is_ep = ep;
 }
 
 static int snd_soc_dapm_check_dynamic_path(struct snd_soc_dapm_context *dapm,
@@ -2510,6 +2495,8 @@
 	int (*connected)(struct snd_soc_dapm_widget *source,
 			 struct snd_soc_dapm_widget *sink))
 {
+	struct snd_soc_dapm_widget *widgets[2];
+	enum snd_soc_dapm_direction dir;
 	struct snd_soc_dapm_path *path;
 	int ret;
 
@@ -2542,13 +2529,14 @@
 	if (!path)
 		return -ENOMEM;
 
-	path->source = wsource;
-	path->sink = wsink;
+	path->node[SND_SOC_DAPM_DIR_IN] = wsource;
+	path->node[SND_SOC_DAPM_DIR_OUT] = wsink;
+	widgets[SND_SOC_DAPM_DIR_IN] = wsource;
+	widgets[SND_SOC_DAPM_DIR_OUT] = wsink;
+
 	path->connected = connected;
 	INIT_LIST_HEAD(&path->list);
 	INIT_LIST_HEAD(&path->list_kcontrol);
-	INIT_LIST_HEAD(&path->list_source);
-	INIT_LIST_HEAD(&path->list_sink);
 
 	if (wsource->is_supply || wsink->is_supply)
 		path->is_supply = 1;
@@ -2586,14 +2574,13 @@
 	}
 
 	list_add(&path->list, &dapm->card->paths);
-	list_add(&path->list_sink, &wsink->sources);
-	list_add(&path->list_source, &wsource->sinks);
+	snd_soc_dapm_for_each_direction(dir)
+		list_add(&path->list_node[dir], &widgets[dir]->edges[dir]);
 
-	dapm_update_widget_flags(wsource);
-	dapm_update_widget_flags(wsink);
-
-	dapm_mark_dirty(wsource, "Route added");
-	dapm_mark_dirty(wsink, "Route added");
+	snd_soc_dapm_for_each_direction(dir) {
+		dapm_update_widget_flags(widgets[dir]);
+		dapm_mark_dirty(widgets[dir], "Route added");
+	}
 
 	if (dapm->card->instantiated && path->connect)
 		dapm_path_invalidate(path);
@@ -3275,6 +3262,7 @@
 snd_soc_dapm_new_control_unlocked(struct snd_soc_dapm_context *dapm,
 			 const struct snd_soc_dapm_widget *widget)
 {
+	enum snd_soc_dapm_direction dir;
 	struct snd_soc_dapm_widget *w;
 	const char *prefix;
 	int ret;
@@ -3329,27 +3317,27 @@
 
 	switch (w->id) {
 	case snd_soc_dapm_mic:
-		w->is_source = 1;
+		w->is_ep = SND_SOC_DAPM_EP_SOURCE;
 		w->power_check = dapm_generic_check_power;
 		break;
 	case snd_soc_dapm_input:
 		if (!dapm->card->fully_routed)
-			w->is_source = 1;
+			w->is_ep = SND_SOC_DAPM_EP_SOURCE;
 		w->power_check = dapm_generic_check_power;
 		break;
 	case snd_soc_dapm_spk:
 	case snd_soc_dapm_hp:
-		w->is_sink = 1;
+		w->is_ep = SND_SOC_DAPM_EP_SINK;
 		w->power_check = dapm_generic_check_power;
 		break;
 	case snd_soc_dapm_output:
 		if (!dapm->card->fully_routed)
-			w->is_sink = 1;
+			w->is_ep = SND_SOC_DAPM_EP_SINK;
 		w->power_check = dapm_generic_check_power;
 		break;
 	case snd_soc_dapm_vmid:
 	case snd_soc_dapm_siggen:
-		w->is_source = 1;
+		w->is_ep = SND_SOC_DAPM_EP_SOURCE;
 		w->power_check = dapm_always_on_check_power;
 		break;
 	case snd_soc_dapm_mux:
@@ -3383,14 +3371,14 @@
 	}
 
 	w->dapm = dapm;
-	INIT_LIST_HEAD(&w->sources);
-	INIT_LIST_HEAD(&w->sinks);
 	INIT_LIST_HEAD(&w->list);
 	INIT_LIST_HEAD(&w->dirty);
 	list_add_tail(&w->list, &dapm->card->widgets);
 
-	w->inputs = -1;
-	w->outputs = -1;
+	snd_soc_dapm_for_each_direction(dir) {
+		INIT_LIST_HEAD(&w->edges[dir]);
+		w->endpoints[dir] = -1;
+	}
 
 	/* machine layer set ups unconnected pins and insertions */
 	w->connected = 1;
@@ -3444,14 +3432,17 @@
 	int ret;
 
 	if (WARN_ON(!config) ||
-	    WARN_ON(list_empty(&w->sources) || list_empty(&w->sinks)))
+	    WARN_ON(list_empty(&w->edges[SND_SOC_DAPM_DIR_OUT]) ||
+		    list_empty(&w->edges[SND_SOC_DAPM_DIR_IN])))
 		return -EINVAL;
 
 	/* We only support a single source and sink, pick the first */
-	source_p = list_first_entry(&w->sources, struct snd_soc_dapm_path,
-				    list_sink);
-	sink_p = list_first_entry(&w->sinks, struct snd_soc_dapm_path,
-				  list_source);
+	source_p = list_first_entry(&w->edges[SND_SOC_DAPM_DIR_OUT],
+				    struct snd_soc_dapm_path,
+				    list_node[SND_SOC_DAPM_DIR_OUT]);
+	sink_p = list_first_entry(&w->edges[SND_SOC_DAPM_DIR_IN],
+				    struct snd_soc_dapm_path,
+				    list_node[SND_SOC_DAPM_DIR_IN]);
 
 	source = source_p->source->priv;
 	sink = sink_p->sink->priv;
@@ -3828,6 +3819,7 @@
 	int event)
 {
 	struct snd_soc_dapm_widget *w;
+	unsigned int ep;
 
 	if (stream == SNDRV_PCM_STREAM_PLAYBACK)
 		w = dai->playback_widget;
@@ -3837,12 +3829,22 @@
 	if (w) {
 		dapm_mark_dirty(w, "stream event");
 
+		if (w->id == snd_soc_dapm_dai_in) {
+			ep = SND_SOC_DAPM_EP_SOURCE;
+			dapm_widget_invalidate_input_paths(w);
+		} else {
+			ep = SND_SOC_DAPM_EP_SINK;
+			dapm_widget_invalidate_output_paths(w);
+		}
+
 		switch (event) {
 		case SND_SOC_DAPM_STREAM_START:
 			w->active = 1;
+			w->is_ep = ep;
 			break;
 		case SND_SOC_DAPM_STREAM_STOP:
 			w->active = 0;
+			w->is_ep = 0;
 			break;
 		case SND_SOC_DAPM_STREAM_SUSPEND:
 		case SND_SOC_DAPM_STREAM_RESUME:
@@ -3850,14 +3852,6 @@
 		case SND_SOC_DAPM_STREAM_PAUSE_RELEASE:
 			break;
 		}
-
-		if (w->id == snd_soc_dapm_dai_in) {
-			w->is_source = w->active;
-			dapm_widget_invalidate_input_paths(w);
-		} else {
-			w->is_sink = w->active;
-			dapm_widget_invalidate_output_paths(w);
-		}
 	}
 }