Merge "clk: Provide OF helper to mark clocks as CRITICAL"

drivers/clk/clk.c

@@ -3863,6 +3863,41 @@ static int parent_ready(struct device_node *np)
 	}
 }
 
+/**
+ * of_clk_detect_critical() - set CLK_IS_CRITICAL flag from Device Tree
+ * @np: Device node pointer associated with clock provider
+ * @index: clock index
+ * @flags: pointer to clk_core->flags
+ *
+ * Detects if the clock-critical property exists and, if so, sets the
+ * corresponding CLK_IS_CRITICAL flag.
+ *
+ * Do not use this function. It exists only for legacy Device Tree
+ * bindings, such as the one-clock-per-node style that are outdated.
+ * Those bindings typically put all clock data into .dts and the Linux
+ * driver has no clock data, thus making it impossible to set this flag
+ * correctly from the driver. Only those drivers may call
+ * of_clk_detect_critical from their setup functions.
+ *
+ * Return: error code or zero on success
+ */
+int of_clk_detect_critical(struct device_node *np,
+					  int index, unsigned long *flags)
+{
+	struct property *prop;
+	const __be32 *cur;
+	uint32_t idx;
+
+	if (!np || !flags)
+		return -EINVAL;
+
+	of_property_for_each_u32(np, "clock-critical", prop, cur, idx)
+		if (index == idx)
+			*flags |= CLK_IS_CRITICAL;
+
+	return 0;
+}
+
 /**
  * of_clk_init() - Scan and init clock providers from the DT
  * @matches: array of compatible values and init functions for providers.

include/linux/clk-provider.h

@@ -788,7 +788,8 @@ int of_clk_get_parent_count(struct device_node *np);
 int of_clk_parent_fill(struct device_node *np, const char **parents,
 		       unsigned int size);
 const char *of_clk_get_parent_name(struct device_node *np, int index);
-
+int of_clk_detect_critical(struct device_node *np, int index,
+			    unsigned long *flags);
 void of_clk_init(const struct of_device_id *matches);
 
 #else /* !CONFIG_OF */
@@ -826,6 +827,13 @@ static inline const char *of_clk_get_parent_name(struct device_node *np,
 {
 	return NULL;
 }
+
+static inline int of_clk_detect_critical(struct device_node *np, int index,
+					  unsigned long *flags)
+{
+	return 0;
+}
+
 #define of_clk_init(matches) \
 	{ while (0); }
 #endif /* CONFIG_OF */