From 872f3ac583cb00c14a4dc86b1511cf98618dd671 Mon Sep 17 00:00:00 2001
From: Szymon Mielczarek <szymonx.mielczarek@linux.intel.com>
Date: Fri, 9 Aug 2019 10:40:34 +0200
Subject: [PATCH] ASoC: dapm: Invalidate only paths reachable for a given stream
Git-commit: 872f3ac583cb00c14a4dc86b1511cf98618dd671
Patch-mainline: v5.4-rc1
References: jsc#SLE-16518

By resetting the cached number of endpoints for all card's widgets we may
overwrite previously cached values for other streams. The situation may
happen especially when running streams simultaneously.

Signed-off-by: Szymon Mielczarek <szymonx.mielczarek@linux.intel.com>
Link: https://lore.kernel.org/r/20190809084034.26220-1-szymonx.mielczarek@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 sound/soc/soc-dapm.c | 50 +++++++++++++++++++++++++++++++++++++-------------
 1 file changed, 37 insertions(+), 13 deletions(-)

diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c
index d09bdca63c62..10819b3e0b98 100644
--- a/sound/soc/soc-dapm.c
+++ b/sound/soc/soc-dapm.c
@@ -1128,6 +1128,34 @@ static int dapm_widget_list_create(struct snd_soc_dapm_widget_list **list,
 	return 0;
 }
 
+/*
+ * Recursively reset the cached number of inputs or outputs for the specified
+ * widget and all widgets that can be reached via incoming or outcoming paths
+ * from the widget.
+ */
+static void invalidate_paths_ep(struct snd_soc_dapm_widget *widget,
+	enum snd_soc_dapm_direction dir)
+{
+	enum snd_soc_dapm_direction rdir = SND_SOC_DAPM_DIR_REVERSE(dir);
+	struct snd_soc_dapm_path *path;
+
+	widget->endpoints[dir] = -1;
+
+	snd_soc_dapm_widget_for_each_path(widget, rdir, path) {
+		if (path->weak || path->is_supply)
+			continue;
+
+		if (path->walking)
+			return;
+
+		if (path->connect) {
+			path->walking = 1;
+			invalidate_paths_ep(path->node[dir], dir);
+			path->walking = 0;
+		}
+	}
+}
+
 /*
  * Common implementation for is_connected_output_ep() and
  * is_connected_input_ep(). The function is inlined since the combined size of
@@ -1257,21 +1285,17 @@ int snd_soc_dapm_dai_get_connected_widgets(struct snd_soc_dai *dai, int stream,
 
 	mutex_lock_nested(&card->dapm_mutex, SND_SOC_DAPM_CLASS_RUNTIME);
 
-	/*
-	 * For is_connected_{output,input}_ep fully discover the graph we need
-	 * to reset the cached number of inputs and outputs.
-	 */
-	list_for_each_entry(w, &card->widgets, list) {
-		w->endpoints[SND_SOC_DAPM_DIR_IN] = -1;
-		w->endpoints[SND_SOC_DAPM_DIR_OUT] = -1;
-	}
-
-	if (stream == SNDRV_PCM_STREAM_PLAYBACK)
-		paths = is_connected_output_ep(dai->playback_widget, &widgets,
+	if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
+		w = dai->playback_widget;
+		invalidate_paths_ep(w, SND_SOC_DAPM_DIR_OUT);
+		paths = is_connected_output_ep(w, &widgets,
 				custom_stop_condition);
-	else
-		paths = is_connected_input_ep(dai->capture_widget, &widgets,
+	} else {
+		w = dai->capture_widget;
+		invalidate_paths_ep(w, SND_SOC_DAPM_DIR_IN);
+		paths = is_connected_input_ep(w, &widgets,
 				custom_stop_condition);
+	}
 
 	/* Drop starting point */
 	list_del(widgets.next);
-- 
2.16.4