[PATCH] power_domain: Add power_domain_get_by_name()

[Marek Vasut <marex@denx.de>]

Implement power_domain_get_by_name() convenience function which parses
DT property 'power-domain-names' and looks up power domain by matching
name.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Patrick Delaunay <patrick.delaunay@foss.st.com>
Cc: Simon Glass <sjg@chromium.org>
---
 drivers/power/domain/power-domain-uclass.c | 14 ++++++++++++++
 include/power-domain.h                     | 21 +++++++++++++++++++++
 2 files changed, 35 insertions(+)

diff --git a/drivers/power/domain/power-domain-uclass.c b/drivers/power/domain/power-domain-uclass.c
index 0c5823ceddf..74c33d4e2e0 100644
--- a/drivers/power/domain/power-domain-uclass.c
+++ b/drivers/power/domain/power-domain-uclass.c
@@ -80,6 +80,20 @@ int power_domain_get_by_index(struct udevice *dev,
 	return 0;
 }
 
+int power_domain_get_by_name(struct udevice *dev,
+			     struct power_domain *power_domain, const char *name)
+{
+	int index;
+
+	index = dev_read_stringlist_search(dev, "power-domain-names", name);
+	if (index < 0) {
+		debug("fdt_stringlist_search() failed: %d\n", index);
+		return index;
+	}
+
+	return power_domain_get_by_index(dev, power_domain, index);
+}
+
 int power_domain_get(struct udevice *dev, struct power_domain *power_domain)
 {
 	return power_domain_get_by_index(dev, power_domain, 0);
diff --git a/include/power-domain.h b/include/power-domain.h
index 113276b5119..2ff6c77cd76 100644
--- a/include/power-domain.h
+++ b/include/power-domain.h
@@ -107,6 +107,27 @@ int power_domain_get_by_index(struct udevice *dev,
 }
 #endif
 
+/**
+ * power_domain_get_by_name - Get the named power domain for a device.
+ *
+ * @dev:		The client device.
+ * @power_domain:	A pointer to a power domain struct to initialize.
+ * @name:		Power domain name to be powered on.
+ *
+ * Return: 0 if OK, or a negative error code.
+ */
+#if CONFIG_IS_ENABLED(POWER_DOMAIN)
+int power_domain_get_by_name(struct udevice *dev,
+			     struct power_domain *power_domain, const char *name);
+#else
+static inline
+int power_domain_get_by_name(struct udevice *dev,
+			     struct power_domain *power_domain, const char *name)
+{
+	return -ENOSYS;
+}
+#endif
+
 /**
  * power_domain_free - Free a previously requested power domain.
  *
-- 
2.35.1