mfd: Remove wm8400 custom cache implementation

Save a useful amount of code by removing the custom cache implementation
for wm8400 and using the regmap cache. Also simplify things by not
separately reseting the CODEC registers, this is a sufficiently infrequent
operation that we can simply invalidate the entire cache when this happens.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/include/linux/mfd/wm8400-private.h b/include/linux/mfd/wm8400-private.h
index 0147b69..2de565b 100644
--- a/include/linux/mfd/wm8400-private.h
+++ b/include/linux/mfd/wm8400-private.h
@@ -24,19 +24,14 @@
 #include <linux/mfd/wm8400.h>
 #include <linux/mutex.h>
 #include <linux/platform_device.h>
-
-struct regmap;
+#include <linux/regmap.h>
 
 #define WM8400_REGISTER_COUNT 0x55
 
 struct wm8400 {
 	struct device *dev;
-
-	struct mutex io_lock;
 	struct regmap *regmap;
 
-	u16 reg_cache[WM8400_REGISTER_COUNT];
-
 	struct platform_device regulators[6];
 };
 
@@ -930,6 +925,11 @@
 
 u16 wm8400_reg_read(struct wm8400 *wm8400, u8 reg);
 int wm8400_block_read(struct wm8400 *wm8400, u8 reg, int count, u16 *data);
-int wm8400_set_bits(struct wm8400 *wm8400, u8 reg, u16 mask, u16 val);
+
+static inline int wm8400_set_bits(struct wm8400 *wm8400, u8 reg,
+				  u16 mask, u16 val)
+{
+	return regmap_update_bits(wm8400->regmap, reg, mask, val);
+}
 
 #endif