3 files changed, 97 insertions, 6 deletions

diff --git a/sound/soc/sof/ipc.c b/sound/soc/sof/ipc.c
index 0034e7a34a1d..53593df95155 100644
--- a/sound/soc/sof/ipc.c
+++ b/sound/soc/sof/ipc.c
@@ -744,9 +744,31 @@ int snd_sof_ipc_set_get_comp_data(struct snd_sof_control *scontrol,
 	struct sof_ipc_fw_ready *ready = &sdev->fw_ready;
 	struct sof_ipc_fw_version *v = &ready->version;
 	struct sof_ipc_ctrl_data_params sparams;
+	struct snd_sof_widget *swidget;
+	bool widget_found = false;
 	size_t send_bytes;
 	int err;
 
+	list_for_each_entry(swidget, &sdev->widget_list, list) {
+		if (swidget->comp_id == scontrol->comp_id) {
+			widget_found = true;
+			break;
+		}
+	}
+
+	if (!widget_found) {
+		dev_err(sdev->dev, "error: can't find widget with id %d\n", scontrol->comp_id);
+		return -EINVAL;
+	}
+
+	/*
+	 * Volatile controls should always be part of static pipelines and the widget use_count
+	 * would always be > 0 in this case. For the others, just return the cached value if the
+	 * widget is not set up.
+	 */
+	if (!swidget->use_count)
+		return 0;
+
 	/* read or write firmware volume */
 	if (scontrol->readback_offset != 0) {
 		/* write/read value header via mmaped region */
diff --git a/sound/soc/sof/sof-audio.c b/sound/soc/sof/sof-audio.c
index 4bed50847f1d..7a4aaabf091e 100644
--- a/sound/soc/sof/sof-audio.c
+++ b/sound/soc/sof/sof-audio.c
@@ -83,7 +83,53 @@ static int sof_widget_kcontrol_setup(struct snd_sof_dev *sdev, struct snd_sof_wi
 	return 0;
 }
 
-static int sof_widget_setup(struct snd_sof_dev *sdev, struct snd_sof_widget *swidget)
+int sof_widget_free(struct snd_sof_dev *sdev, struct snd_sof_widget *swidget)
+{
+	struct sof_ipc_free ipc_free = {
+		.hdr = {
+			.size = sizeof(ipc_free),
+			.cmd = SOF_IPC_GLB_TPLG_MSG,
+		},
+		.id = swidget->comp_id,
+	};
+	struct sof_ipc_reply reply;
+	int ret;
+
+	if (!swidget->private)
+		return 0;
+
+	/* only free when use_count is 0 */
+	if (--swidget->use_count)
+		return 0;
+
+	switch (swidget->id) {
+	case snd_soc_dapm_scheduler:
+		ipc_free.hdr.cmd |= SOF_IPC_TPLG_PIPE_FREE;
+		break;
+	case snd_soc_dapm_buffer:
+		ipc_free.hdr.cmd |= SOF_IPC_TPLG_BUFFER_FREE;
+		break;
+	default:
+		ipc_free.hdr.cmd |= SOF_IPC_TPLG_COMP_FREE;
+		break;
+	}
+
+	ret = sof_ipc_tx_message(sdev->ipc, ipc_free.hdr.cmd, &ipc_free, sizeof(ipc_free),
+				 &reply, sizeof(reply));
+	if (ret < 0) {
+		dev_err(sdev->dev, "error: failed to free widget %s\n", swidget->widget->name);
+		swidget->use_count++;
+		return ret;
+	}
+
+	swidget->complete = 0;
+	dev_dbg(sdev->dev, "widget %s freed\n", swidget->widget->name);
+
+	return 0;
+}
+EXPORT_SYMBOL(sof_widget_free);
+
+int sof_widget_setup(struct snd_sof_dev *sdev, struct snd_sof_widget *swidget)
 {
 	struct sof_ipc_pipe_new *pipeline;
 	struct sof_ipc_comp_reply r;
@@ -97,11 +143,15 @@ static int sof_widget_setup(struct snd_sof_dev *sdev, struct snd_sof_widget *swi
 	if (!swidget->private)
 		return 0;
 
+	/* widget already set up */
+	if (++swidget->use_count > 1)
+		return 0;
+
 	ret = sof_pipeline_core_enable(sdev, swidget);
 	if (ret < 0) {
 		dev_err(sdev->dev, "error: failed to enable target core: %d for widget %s\n",
 			ret, swidget->widget->name);
-		return ret;
+		goto use_count_dec;
 	}
 
 	switch (swidget->id) {
@@ -134,7 +184,7 @@ static int sof_widget_setup(struct snd_sof_dev *sdev, struct snd_sof_widget *swi
 	}
 	if (ret < 0) {
 		dev_err(sdev->dev, "error: failed to load widget %s\n", swidget->widget->name);
-		return ret;
+		goto use_count_dec;
 	}
 
 	/* restore kcontrols for widget */
@@ -147,8 +197,13 @@ static int sof_widget_setup(struct snd_sof_dev *sdev, struct snd_sof_widget *swi
 
 	dev_dbg(sdev->dev, "widget %s setup complete\n", swidget->widget->name);
 
+	return 0;
+
+use_count_dec:
+	swidget->use_count--;
 	return ret;
 }
+EXPORT_SYMBOL(sof_widget_setup);
 
 /*
  * helper to determine if there are only D0i3 compatible
@@ -258,6 +313,9 @@ int sof_set_up_pipelines(struct device *dev)
 
 	/* restore pipeline components */
 	list_for_each_entry_reverse(swidget, &sdev->widget_list, list) {
+		/* reset widget use_count after resuming */
+		swidget->use_count = 0;
+
 		ret = sof_widget_setup(sdev, swidget);
 		if (ret < 0)
 			return ret;
@@ -325,16 +383,23 @@ int sof_set_up_pipelines(struct device *dev)
 	return 0;
 }
 
-/* This function doesn't free widgets. It only resets the set up status for all routes */
+/*
+ * This function doesn't free widgets. It only resets the set up status for all routes and
+ * use_count for all widgets.
+ */
 void sof_tear_down_pipelines(struct device *dev)
 {
 	struct snd_sof_dev *sdev = dev_get_drvdata(dev);
+	struct snd_sof_widget *swidget;
 	struct snd_sof_route *sroute;
 
 	/*
-	 * No need to protect sroute->setup as this function is called only during the suspend
-	 * callback and all streams should be suspended by then
+	 * No need to protect swidget->use_count and sroute->setup as this function is called only
+	 * during the suspend callback and all streams should be suspended by then
 	 */
+	list_for_each_entry(swidget, &sdev->widget_list, list)
+		swidget->use_count = 0;
+
 	list_for_each_entry(sroute, &sdev->route_list, list)
 		sroute->setup = false;
 }
diff --git a/sound/soc/sof/sof-audio.h b/sound/soc/sof/sof-audio.h
index f1f630028c21..6ac623137026 100644
--- a/sound/soc/sof/sof-audio.h
+++ b/sound/soc/sof/sof-audio.h
@@ -89,6 +89,7 @@ struct snd_sof_widget {
 	int comp_id;
 	int pipeline_id;
 	int complete;
+	int use_count; /* use_count will be protected by the PCM mutex held by the core */
 	int core;
 	int id;
 
@@ -252,4 +253,7 @@ bool snd_sof_dsp_only_d0i3_compatible_stream_active(struct snd_sof_dev *sdev);
 int sof_machine_register(struct snd_sof_dev *sdev, void *pdata);
 void sof_machine_unregister(struct snd_sof_dev *sdev, void *pdata);
 
+int sof_widget_setup(struct snd_sof_dev *sdev, struct snd_sof_widget *swidget);
+int sof_widget_free(struct snd_sof_dev *sdev, struct snd_sof_widget *swidget);
+
 #endif