1 files changed, 44 insertions, 10 deletions

diff --git a/drivers/soc/qcom/smem_state.c b/drivers/soc/qcom/smem_state.c
index d2b558438deb..cc5be8019b6a 100644
--- a/drivers/soc/qcom/smem_state.c
+++ b/drivers/soc/qcom/smem_state.c
@@ -3,6 +3,7 @@
  * Copyright (c) 2015, Sony Mobile Communications Inc.
  * Copyright (c) 2012-2013, The Linux Foundation. All rights reserved.
  */
+#include <linux/cleanup.h>
 #include <linux/device.h>
 #include <linux/list.h>
 #include <linux/module.h>
@@ -60,20 +61,15 @@ static struct qcom_smem_state *of_node_to_state(struct device_node *np)
 {
 	struct qcom_smem_state *state;
 
-	mutex_lock(&list_lock);
+	guard(mutex)(&list_lock);
 
 	list_for_each_entry(state, &smem_states, list) {
 		if (state->of_node == np) {
 			kref_get(&state->refcount);
-			goto unlock;
+			return state;
 		}
 	}
-	state = ERR_PTR(-EPROBE_DEFER);
-
-unlock:
-	mutex_unlock(&list_lock);
-
-	return state;
+	return ERR_PTR(-EPROBE_DEFER);
 }
 
 /**
@@ -116,7 +112,8 @@ struct qcom_smem_state *qcom_smem_state_get(struct device *dev,
 
 	if (args.args_count != 1) {
 		dev_err(dev, "invalid #qcom,smem-state-cells\n");
-		return ERR_PTR(-EINVAL);
+		state = ERR_PTR(-EINVAL);
+		goto put;
 	}
 
 	state = of_node_to_state(args.np);
@@ -136,6 +133,7 @@ static void qcom_smem_state_release(struct kref *ref)
 	struct qcom_smem_state *state = container_of(ref, struct qcom_smem_state, refcount);
 
 	list_del(&state->list);
+	of_node_put(state->of_node);
 	kfree(state);
 }
 
@@ -151,6 +149,42 @@ void qcom_smem_state_put(struct qcom_smem_state *state)
 }
 EXPORT_SYMBOL_GPL(qcom_smem_state_put);
 
+static void devm_qcom_smem_state_release(struct device *dev, void *res)
+{
+	qcom_smem_state_put(*(struct qcom_smem_state **)res);
+}
+
+/**
+ * devm_qcom_smem_state_get() - acquire handle to a devres managed state
+ * @dev:	client device pointer
+ * @con_id:	name of the state to lookup
+ * @bit:	flags from the state reference, indicating which bit's affected
+ *
+ * Returns handle to the state, or ERR_PTR(). qcom_smem_state_put() is called
+ * automatically when @dev is removed.
+ */
+struct qcom_smem_state *devm_qcom_smem_state_get(struct device *dev,
+						 const char *con_id,
+						 unsigned *bit)
+{
+	struct qcom_smem_state **ptr, *state;
+
+	ptr = devres_alloc(devm_qcom_smem_state_release, sizeof(*ptr), GFP_KERNEL);
+	if (!ptr)
+		return ERR_PTR(-ENOMEM);
+
+	state = qcom_smem_state_get(dev, con_id, bit);
+	if (!IS_ERR(state)) {
+		*ptr = state;
+		devres_add(dev, ptr);
+	} else {
+		devres_free(ptr);
+	}
+
+	return state;
+}
+EXPORT_SYMBOL_GPL(devm_qcom_smem_state_get);
+
 /**
  * qcom_smem_state_register() - register a new state
  * @of_node:	of_node used for matching client lookups
@@ -169,7 +203,7 @@ struct qcom_smem_state *qcom_smem_state_register(struct device_node *of_node,
 
 	kref_init(&state->refcount);
 
-	state->of_node = of_node;
+	state->of_node = of_node_get(of_node);
 	state->ops = *ops;
 	state->priv = priv;