2 files changed, 100 insertions, 0 deletions

diff --git a/drivers/firmware/ti_sci.c b/drivers/firmware/ti_sci.c
index 3fbbb61012c4..852043531233 100644
--- a/drivers/firmware/ti_sci.c
+++ b/drivers/firmware/ti_sci.c
@@ -1764,6 +1764,89 @@ const struct ti_sci_handle *devm_ti_sci_get_handle(struct device *dev)
 }
 EXPORT_SYMBOL_GPL(devm_ti_sci_get_handle);
 
+/**
+ * ti_sci_get_by_phandle() - Get the TI SCI handle using DT phandle
+ * @np:		device node
+ * @property:	property name containing phandle on TISCI node
+ *
+ * NOTE: The function does not track individual clients of the framework
+ * and is expected to be maintained by caller of TI SCI protocol library.
+ * ti_sci_put_handle must be balanced with successful ti_sci_get_by_phandle
+ * Return: pointer to handle if successful, else:
+ * -EPROBE_DEFER if the instance is not ready
+ * -ENODEV if the required node handler is missing
+ * -EINVAL if invalid conditions are encountered.
+ */
+const struct ti_sci_handle *ti_sci_get_by_phandle(struct device_node *np,
+						  const char *property)
+{
+	struct ti_sci_handle *handle = NULL;
+	struct device_node *ti_sci_np;
+	struct ti_sci_info *info;
+	struct list_head *p;
+
+	if (!np) {
+		pr_err("I need a device pointer\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	ti_sci_np = of_parse_phandle(np, property, 0);
+	if (!ti_sci_np)
+		return ERR_PTR(-ENODEV);
+
+	mutex_lock(&ti_sci_list_mutex);
+	list_for_each(p, &ti_sci_list) {
+		info = list_entry(p, struct ti_sci_info, node);
+		if (ti_sci_np == info->dev->of_node) {
+			handle = &info->handle;
+			info->users++;
+			break;
+		}
+	}
+	mutex_unlock(&ti_sci_list_mutex);
+	of_node_put(ti_sci_np);
+
+	if (!handle)
+		return ERR_PTR(-EPROBE_DEFER);
+
+	return handle;
+}
+EXPORT_SYMBOL_GPL(ti_sci_get_by_phandle);
+
+/**
+ * devm_ti_sci_get_by_phandle() - Managed get handle using phandle
+ * @dev:	Device pointer requesting TISCI handle
+ * @property:	property name containing phandle on TISCI node
+ *
+ * NOTE: This releases the handle once the device resources are
+ * no longer needed. MUST NOT BE released with ti_sci_put_handle.
+ * The function does not track individual clients of the framework
+ * and is expected to be maintained by caller of TI SCI protocol library.
+ *
+ * Return: 0 if all went fine, else corresponding error.
+ */
+const struct ti_sci_handle *devm_ti_sci_get_by_phandle(struct device *dev,
+						       const char *property)
+{
+	const struct ti_sci_handle *handle;
+	const struct ti_sci_handle **ptr;
+
+	ptr = devres_alloc(devm_ti_sci_release, sizeof(*ptr), GFP_KERNEL);
+	if (!ptr)
+		return ERR_PTR(-ENOMEM);
+	handle = ti_sci_get_by_phandle(dev_of_node(dev), property);
+
+	if (!IS_ERR(handle)) {
+		*ptr = handle;
+		devres_add(dev, ptr);
+	} else {
+		devres_free(ptr);
+	}
+
+	return handle;
+}
+EXPORT_SYMBOL_GPL(devm_ti_sci_get_by_phandle);
+
 static int tisci_reboot_handler(struct notifier_block *nb, unsigned long mode,
 				void *cmd)
 {
diff --git a/include/linux/soc/ti/ti_sci_protocol.h b/include/linux/soc/ti/ti_sci_protocol.h
index 18435e5c6364..515587e9d373 100644
--- a/include/linux/soc/ti/ti_sci_protocol.h
+++ b/include/linux/soc/ti/ti_sci_protocol.h
@@ -217,6 +217,10 @@ struct ti_sci_handle {
 const struct ti_sci_handle *ti_sci_get_handle(struct device *dev);
 int ti_sci_put_handle(const struct ti_sci_handle *handle);
 const struct ti_sci_handle *devm_ti_sci_get_handle(struct device *dev);
+const struct ti_sci_handle *ti_sci_get_by_phandle(struct device_node *np,
+						  const char *property);
+const struct ti_sci_handle *devm_ti_sci_get_by_phandle(struct device *dev,
+						       const char *property);
 
 #else	/* CONFIG_TI_SCI_PROTOCOL */
 
@@ -236,6 +240,19 @@ const struct ti_sci_handle *devm_ti_sci_get_handle(struct device *dev)
 	return ERR_PTR(-EINVAL);
 }
 
+static inline
+const struct ti_sci_handle *ti_sci_get_by_phandle(struct device_node *np,
+						  const char *property)
+{
+	return ERR_PTR(-EINVAL);
+}
+
+static inline
+const struct ti_sci_handle *devm_ti_sci_get_by_phandle(struct device *dev,
+						       const char *property)
+{
+	return ERR_PTR(-EINVAL);
+}
 #endif	/* CONFIG_TI_SCI_PROTOCOL */
 
 #endif	/* __TISCI_PROTOCOL_H */