[U-Boot] [PATCH v7 08/12] dm: regmap: Implement simple regmap_read & regmap_write

Paul Burton paul.burton at imgtec.com
Thu Sep 8 08:47:35 CEST 2016


The regmap_read & regmap_write functions were previously declared in
regmap.h but not implemented anywhere. The regmap implementation &
commit message of 6f98b7504f70 ("dm: Add support for register maps
(regmap)") indicate that only memory mapped accesses are supported for
now, so providing simple implementations of regmap_read & regmap_write
is trivial. The access size is presumed to be 4 bytes & endianness is
presumed native, which are the defaults for the regmap code in Linux.

Signed-off-by: Paul Burton <paul.burton at imgtec.com>
Reviewed-by: Simon Glass <sjg at chromium.org>

---

Changes in v7:
- Use map_physmem instead of ioremap, as it's more generic
- Use plain readl & writel, not __raw_ variants

Changes in v6: None
Changes in v5: None
Changes in v4:
- Tweak whitespace

Changes in v3: None
Changes in v2:
- New patch

 drivers/core/regmap.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/drivers/core/regmap.c b/drivers/core/regmap.c
index 0299ff0..c68bcba 100644
--- a/drivers/core/regmap.c
+++ b/drivers/core/regmap.c
@@ -13,6 +13,8 @@
 #include <mapmem.h>
 #include <regmap.h>
 
+#include <asm/io.h>
+
 DECLARE_GLOBAL_DATA_PTR;
 
 static struct regmap *regmap_alloc_count(int count)
@@ -117,3 +119,21 @@ int regmap_uninit(struct regmap *map)
 
 	return 0;
 }
+
+int regmap_read(struct regmap *map, uint offset, uint *valp)
+{
+	uint32_t *ptr = map_physmem(map->base + offset, 4, MAP_NOCACHE);
+
+	*valp = le32_to_cpu(readl(ptr));
+
+	return 0;
+}
+
+int regmap_write(struct regmap *map, uint offset, uint val)
+{
+	uint32_t *ptr = map_physmem(map->base + offset, 4, MAP_NOCACHE);
+
+	writel(cpu_to_le32(val), ptr);
+
+	return 0;
+}
-- 
2.9.3



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