regulator: core: Allow drivers to pass in a regmap

Since many regulators use regmap for register I/O and since there's quite
a few very common patterns in the code allow drivers to pass in a regmap
to the core for use in generic code.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@ti.com>

drivers/regulator/core.c

@@ -24,6 +24,7 @@
 #include <linux/suspend.h>
 #include <linux/delay.h>
 #include <linux/of.h>
+#include <linux/regmap.h>
 #include <linux/regulator/of_regulator.h>
 #include <linux/regulator/consumer.h>
 #include <linux/regulator/driver.h>
@@ -2877,6 +2878,7 @@ regulator_register(const struct regulator_desc *regulator_desc,
 	rdev->reg_data = config->driver_data;
 	rdev->owner = regulator_desc->owner;
 	rdev->desc = regulator_desc;
+	rdev->regmap = config->regmap;
 	INIT_LIST_HEAD(&rdev->consumer_list);
 	INIT_LIST_HEAD(&rdev->list);
 	BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);

include/linux/regulator/driver.h

@@ -19,6 +19,7 @@
 #include <linux/notifier.h>
 #include <linux/regulator/consumer.h>
 
+struct regmap;
 struct regulator_dev;
 struct regulator_init_data;
 
@@ -187,12 +188,14 @@ struct regulator_desc {
  * @driver_data: private regulator data
  * @of_node: OpenFirmware node to parse for device tree bindings (may be
  *           NULL).
+ * @regmap: regmap to use for core regmap helpers
  */
 struct regulator_config {
 	struct device *dev;
 	const struct regulator_init_data *init_data;
 	void *driver_data;
 	struct device_node *of_node;
+	struct regmap *regmap;
 };
 
 /*
@@ -223,6 +226,7 @@ struct regulator_dev {
 	struct device dev;
 	struct regulation_constraints *constraints;
 	struct regulator *supply;	/* for tree */
+	struct regmap *regmap;
 
 	struct delayed_work disable_work;
 	int deferred_disables;