clk: Extend clock control with an optional data field

Some systems require more than a single ID to identify and configure any
clock provider. For those scenarios add an optional data field to the
clock control structure.
Reviewed-by: NTom Rini <trini@konsulko.com>
Signed-off-by: NAndreas Dannenberg <dannenberg@ti.com>
Signed-off-by: NLokesh Vutla <lokeshvutla@ti.com>

include/clk.h

@@ -40,10 +40,12 @@ struct udevice;
  *
  * @dev: The device which implements the clock signal.
  * @id: The clock signal ID within the provider.
+ * @data: An optional data field for scenarios where a single integer ID is not
+ *	  sufficient. If used, it can be populated through an .of_xlate op and
+ *	  processed during the various clock ops.
  *
- * Currently, the clock API assumes that a single integer ID is enough to
- * identify and configure any clock signal for any clock provider. If this
- * assumption becomes invalid in the future, the struct could be expanded to
+ * Should additional information to identify and configure any clock signal
+ * for any provider be required in the future, the struct could be expanded to
  * either (a) add more fields to allow clock providers to store additional
  * information, or (b) replace the id field with an opaque pointer, which the
  * provider would dynamically allocated during its .of_xlate op, and process
@@ -53,10 +55,10 @@ struct udevice;
 struct clk {
 	struct udevice *dev;
 	/*
-	 * Written by of_xlate. We assume a single id is enough for now. In the
-	 * future, we might add more fields here.
+	 * Written by of_xlate. In the future, we might add more fields here.
 	 */
 	unsigned long id;
+	unsigned long data;
 };
 
 /**