[U-Boot] [PATCH v2 1/2] regmap: add regmap_update_bits() helper

[Neil Armstrong]

Add the regmap_update_bits() to simply the read/modify/write of registers
in a single command. The function is taken from Linux regmap
implementation.

Signed-off-by: Neil Armstrong <narmstrong at baylibre.com>
---
 drivers/core/regmap.c | 14 ++++++++++++++
 include/regmap.h      | 10 ++++++++++
 2 files changed, 24 insertions(+)

diff --git a/drivers/core/regmap.c b/drivers/core/regmap.c
index 8a0e00f..9fae252 100644
--- a/drivers/core/regmap.c
+++ b/drivers/core/regmap.c
@@ -147,3 +147,17 @@ int regmap_write(struct regmap *map, uint offset, uint val)
 
 	return 0;
 }
+
+int regmap_update_bits(struct regmap *map, uint offset, uint mask, uint val)
+{
+	uint reg;
+	int ret;
+
+	ret = regmap_read(map, offset, &reg);
+	if (ret)
+		return ret;
+
+	reg &= ~mask;
+
+	return regmap_write(map, offset, reg | val);
+}
diff --git a/include/regmap.h b/include/regmap.h
index 493a5d8..1349d40 100644
--- a/include/regmap.h
+++ b/include/regmap.h
@@ -47,6 +47,16 @@ int regmap_read(struct regmap *map, uint offset, uint *valp);
 	regmap_read(map, (uint32_t *)(ptr)->member - (uint32_t *)(ptr), valp)
 
 /**
+ * regmap_update_bits() - Perform a read/modify/write using a mask
+ *
+ * @map:	The map returned by regmap_init_mem*()
+ * @offset:	Offset of the memory
+ * @mask:	Mask to apply to the read value
+ * @val:	Value to apply to the value to write
+ */
+int regmap_update_bits(struct regmap *map, uint offset, uint mask, uint val);
+
+/**
  * regmap_init_mem() - Set up a new register map that uses memory access
  *
  * Use regmap_uninit() to free it.
-- 
2.7.4