1 files changed, 77 insertions, 13 deletions

diff --git a/drivers/remoteproc/qcom_common.c b/drivers/remoteproc/qcom_common.c
index 9028cea2d81e..48b399af9c83 100644
--- a/drivers/remoteproc/qcom_common.c
+++ b/drivers/remoteproc/qcom_common.c
@@ -12,6 +12,7 @@
 #include <linux/module.h>
 #include <linux/notifier.h>
 #include <linux/remoteproc.h>
+#include <linux/remoteproc/qcom_rproc.h>
 #include <linux/rpmsg/qcom_glink.h>
 #include <linux/rpmsg/qcom_smd.h>
 #include <linux/soc/qcom/mdt_loader.h>
@@ -23,7 +24,14 @@
 #define to_smd_subdev(d) container_of(d, struct qcom_rproc_subdev, subdev)
 #define to_ssr_subdev(d) container_of(d, struct qcom_rproc_ssr, subdev)
 
-static BLOCKING_NOTIFIER_HEAD(ssr_notifiers);
+struct qcom_ssr_subsystem {
+	const char *name;
+	struct srcu_notifier_head notifier_list;
+	struct list_head list;
+};
+
+static LIST_HEAD(qcom_ssr_subsystem_list);
+static DEFINE_MUTEX(qcom_ssr_subsys_lock);
 
 static int glink_subdev_start(struct rproc_subdev *subdev)
 {
@@ -189,37 +197,83 @@ void qcom_remove_smd_subdev(struct rproc *rproc, struct qcom_rproc_subdev *smd)
 }
 EXPORT_SYMBOL_GPL(qcom_remove_smd_subdev);
 
+static struct qcom_ssr_subsystem *qcom_ssr_get_subsys(const char *name)
+{
+	struct qcom_ssr_subsystem *info;
+
+	mutex_lock(&qcom_ssr_subsys_lock);
+	/* Match in the global qcom_ssr_subsystem_list with name */
+	list_for_each_entry(info, &qcom_ssr_subsystem_list, list)
+		if (!strcmp(info->name, name))
+			goto out;
+
+	info = kzalloc(sizeof(*info), GFP_KERNEL);
+	if (!info) {
+		info = ERR_PTR(-ENOMEM);
+		goto out;
+	}
+	info->name = kstrdup_const(name, GFP_KERNEL);
+	srcu_init_notifier_head(&info->notifier_list);
+
+	/* Add to global notification list */
+	list_add_tail(&info->list, &qcom_ssr_subsystem_list);
+
+out:
+	mutex_unlock(&qcom_ssr_subsys_lock);
+	return info;
+}
+
 /**
  * qcom_register_ssr_notifier() - register SSR notification handler
- * @nb:		notifier_block to notify for restart notifications
+ * @name:	Subsystem's SSR name
+ * @nb:		notifier_block to be invoked upon subsystem's state change
  *
- * Returns 0 on success, negative errno on failure.
+ * This registers the @nb notifier block as part the notifier chain for a
+ * remoteproc associated with @name. The notifier block's callback
+ * will be invoked when the remote processor's SSR events occur
+ * (pre/post startup and pre/post shutdown).
  *
- * This register the @notify function as handler for restart notifications. As
- * remote processors are stopped this function will be called, with the SSR
- * name passed as a parameter.
+ * Return: a subsystem cookie on success, ERR_PTR on failure.
  */
-int qcom_register_ssr_notifier(struct notifier_block *nb)
+void *qcom_register_ssr_notifier(const char *name, struct notifier_block *nb)
 {
-	return blocking_notifier_chain_register(&ssr_notifiers, nb);
+	struct qcom_ssr_subsystem *info;
+
+	info = qcom_ssr_get_subsys(name);
+	if (IS_ERR(info))
+		return info;
+
+	srcu_notifier_chain_register(&info->notifier_list, nb);
+
+	return &info->notifier_list;
 }
 EXPORT_SYMBOL_GPL(qcom_register_ssr_notifier);
 
 /**
  * qcom_unregister_ssr_notifier() - unregister SSR notification handler
+ * @notify:	subsystem cookie returned from qcom_register_ssr_notifier
  * @nb:		notifier_block to unregister
+ *
+ * This function will unregister the notifier from the particular notifier
+ * chain.
+ *
+ * Return: 0 on success, %ENOENT otherwise.
  */
-void qcom_unregister_ssr_notifier(struct notifier_block *nb)
+int qcom_unregister_ssr_notifier(void *notify, struct notifier_block *nb)
 {
-	blocking_notifier_chain_unregister(&ssr_notifiers, nb);
+	return srcu_notifier_chain_unregister(notify, nb);
 }
 EXPORT_SYMBOL_GPL(qcom_unregister_ssr_notifier);
 
 static void ssr_notify_unprepare(struct rproc_subdev *subdev)
 {
 	struct qcom_rproc_ssr *ssr = to_ssr_subdev(subdev);
+	struct qcom_ssr_notify_data data = {
+		.name = ssr->info->name,
+		.crashed = false,
+	};
 
-	blocking_notifier_call_chain(&ssr_notifiers, 0, (void *)ssr->name);
+	srcu_notifier_call_chain(&ssr->info->notifier_list, 0, &data);
 }
 
 /**
@@ -229,12 +283,21 @@ static void ssr_notify_unprepare(struct rproc_subdev *subdev)
  * @ssr_name:	identifier to use for notifications originating from @rproc
  *
  * As the @ssr is registered with the @rproc SSR events will be sent to all
- * registered listeners in the system as the remoteproc is shut down.
+ * registered listeners for the remoteproc when it's SSR events occur
+ * (pre/post startup and pre/post shutdown).
  */
 void qcom_add_ssr_subdev(struct rproc *rproc, struct qcom_rproc_ssr *ssr,
 			 const char *ssr_name)
 {
-	ssr->name = ssr_name;
+	struct qcom_ssr_subsystem *info;
+
+	info = qcom_ssr_get_subsys(ssr_name);
+	if (IS_ERR(info)) {
+		dev_err(&rproc->dev, "Failed to add ssr subdevice\n");
+		return;
+	}
+
+	ssr->info = info;
 	ssr->subdev.unprepare = ssr_notify_unprepare;
 
 	rproc_add_subdev(rproc, &ssr->subdev);
@@ -249,6 +312,7 @@ EXPORT_SYMBOL_GPL(qcom_add_ssr_subdev);
 void qcom_remove_ssr_subdev(struct rproc *rproc, struct qcom_rproc_ssr *ssr)
 {
 	rproc_remove_subdev(rproc, &ssr->subdev);
+	ssr->info = NULL;
 }
 EXPORT_SYMBOL_GPL(qcom_remove_ssr_subdev);