diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index 4de137bc..e2200f2 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -21,12 +21,24 @@
 struct spi_device;
 
 /**
+ * Default value for a register.  We use an array of structs rather
+ * than a simple array as many modern devices have very sparse
+ * register maps.
+ *
+ * @reg: Register address.
+ * @def: Register default value.
+ */
+struct reg_default {
+	unsigned int reg;
+	unsigned int def;
+};
+
+/**
  * Configuration for the register map of a device.
  *
  * @reg_bits: Number of bits in a register address, mandatory.
  * @val_bits: Number of bits in a register value, mandatory.
  *
- * @max_register: Optional, specifies the maximum valid register index.
  * @writeable_reg: Optional callback returning true if the register
  *                 can be written to.
  * @readable_reg: Optional callback returning true if the register
@@ -36,16 +48,24 @@
  * @precious_reg: Optional callback returning true if the rgister
  *                should not be read outside of a call from the driver
  *                (eg, a clear on read interrupt status register).
+ *
+ * @max_register: Optional, specifies the maximum valid register index.
+ * @reg_defaults: Power on reset values for registers (for use with
+ *                register cache support).
+ * @num_reg_defaults: Number of elements in reg_defaults.
  */
 struct regmap_config {
 	int reg_bits;
 	int val_bits;
 
-	unsigned int max_register;
 	bool (*writeable_reg)(struct device *dev, unsigned int reg);
 	bool (*readable_reg)(struct device *dev, unsigned int reg);
 	bool (*volatile_reg)(struct device *dev, unsigned int reg);
 	bool (*precious_reg)(struct device *dev, unsigned int reg);
+
+	unsigned int max_register;
+	struct reg_default *reg_defaults;
+	int num_reg_defaults;
 };
 
 typedef int (*regmap_hw_write)(struct device *dev, const void *data,