regmap: allow busses to request formatting with specific endianness
Add a field to struct regmap_bus that allows bus drivers to request that
register addresses and values be formatted with a specific endianness.
The default endianness is unchanged from current operation: Big.
Implement native endian formatting/parsing for 16- and 32-bit values.
This will be enough to support regmap-mmio.c.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index 56af22e..26136b5 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -43,6 +43,14 @@
#ifdef CONFIG_REGMAP
+enum regmap_endian {
+ /* Unspecified -> 0 -> Backwards compatible default */
+ REGMAP_ENDIAN_DEFAULT = 0,
+ REGMAP_ENDIAN_BIG,
+ REGMAP_ENDIAN_LITTLE,
+ REGMAP_ENDIAN_NATIVE,
+};
+
/**
* Configuration for the register map of a device.
*
@@ -84,6 +92,12 @@
* @reg_defaults_raw: Power on reset values for registers (for use with
* register cache support).
* @num_reg_defaults_raw: Number of elements in reg_defaults_raw.
+ * @reg_format_endian: Endianness for formatted register addresses. If this is
+ * DEFAULT, the @reg_format_endian_default value from the
+ * regmap bus is used.
+ * @val_format_endian: Endianness for formatted register values. If this is
+ * DEFAULT, the @reg_format_endian_default value from the
+ * regmap bus is used.
*/
struct regmap_config {
const char *name;
@@ -109,6 +123,9 @@
u8 write_flag_mask;
bool use_single_rw;
+
+ enum regmap_endian reg_format_endian;
+ enum regmap_endian val_format_endian;
};
typedef int (*regmap_hw_write)(void *context, const void *data,
@@ -133,6 +150,12 @@
* data.
* @read_flag_mask: Mask to be set in the top byte of the register when doing
* a read.
+ * @reg_format_endian_default: Default endianness for formatted register
+ * addresses. Used when the regmap_config specifies DEFAULT. If this is
+ * DEFAULT, BIG is assumed.
+ * @val_format_endian_default: Default endianness for formatted register
+ * values. Used when the regmap_config specifies DEFAULT. If this is
+ * DEFAULT, BIG is assumed.
*/
struct regmap_bus {
bool fast_io;
@@ -141,6 +164,8 @@
regmap_hw_read read;
regmap_hw_free_context free_context;
u8 read_flag_mask;
+ enum regmap_endian reg_format_endian_default;
+ enum regmap_endian val_format_endian_default;
};
struct regmap *regmap_init(struct device *dev,