From: Neil Armstrong <narmstrong@baylibre.com>
Date: Fri, 27 Apr 2018 09:56:14 +0000 (+0200)
Subject: regmap: add regmap_update_bits() helper
X-Git-Tag: v2018.07-rc1~197
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=285cbcf97f2b1dcadedb6835b3e9662c7fba0fe2;p=oweals%2Fu-boot.git

regmap: add regmap_update_bits() helper

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@baylibre.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
---

diff --git a/drivers/core/regmap.c b/drivers/core/regmap.c
index fabcc5f53a..8e5c3bcf61 100644
--- a/drivers/core/regmap.c
+++ b/drivers/core/regmap.c
@@ -132,3 +132,17 @@ 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 e96c79dd26..6a574eaa41 100644
--- a/include/regmap.h
+++ b/include/regmap.h
@@ -42,6 +42,16 @@ int regmap_read(struct regmap *map, uint offset, uint *valp);
 #define regmap_read32(map, ptr, member, 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
  *