[PATCH v3 4/9] regmap: Allow left shifting register offset before access

[Pratyush Yadav]

Drivers can configure it to adjust the final read/write location.

Signed-off-by: Pratyush Yadav <p.ya...@ti.com>
Reviewed-by: Simon Glass <s...@chromium.org>
---

Notes:
    No changes in v3.

 drivers/core/regmap.c | 6 +++++-
 include/regmap.h      | 6 ++++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/core/regmap.c b/drivers/core/regmap.c
index c71b961234..173ae80890 100644
--- a/drivers/core/regmap.c
+++ b/drivers/core/regmap.c
@@ -261,8 +261,10 @@ struct regmap *devm_regmap_init(struct udevice *dev,
                return ERR_PTR(rc);
 
        map = *mapp;
-       if (config)
+       if (config) {
                map->width = config->width;
+               map->reg_offset_shift = config->reg_offset_shift;
+       }
 
        devres_add(dev, mapp);
        return *mapp;
@@ -349,6 +351,7 @@ int regmap_raw_read_range(struct regmap *map, uint 
range_num, uint offset,
        }
        range = &map->ranges[range_num];
 
+       offset <<= map->reg_offset_shift;
        if (offset + val_len > range->size) {
                debug("%s: offset/size combination invalid\n", __func__);
                return -ERANGE;
@@ -458,6 +461,7 @@ int regmap_raw_write_range(struct regmap *map, uint 
range_num, uint offset,
        }
        range = &map->ranges[range_num];
 
+       offset <<= map->reg_offset_shift;
        if (offset + val_len > range->size) {
                debug("%s: offset/size combination invalid\n", __func__);
                return -ERANGE;
diff --git a/include/regmap.h b/include/regmap.h
index 19474e6de1..e6c59dfbce 100644
--- a/include/regmap.h
+++ b/include/regmap.h
@@ -82,9 +82,12 @@ struct regmap_bus;
  *
  * @width:             Width of the read/write operations. Defaults to
  *                     REGMAP_SIZE_32 if set to 0.
+ * @reg_offset_shift   Left shift the register offset by this value before
+ *                     performing read or write.
  */
 struct regmap_config {
        enum regmap_size_t width;
+       u32 reg_offset_shift;
 };
 
 /**
@@ -92,12 +95,15 @@ struct regmap_config {
  *
  * @width:             Width of the read/write operations. Defaults to
  *                     REGMAP_SIZE_32 if set to 0.
+ * @reg_offset_shift   Left shift the register offset by this value before
+ *                     performing read or write.
  * @range_count:       Number of ranges available within the map
  * @ranges:            Array of ranges
  */
 struct regmap {
        enum regmap_endianness_t endianness;
        enum regmap_size_t width;
+       u32 reg_offset_shift;
        int range_count;
        struct regmap_range ranges[0];
 };
-- 
2.28.0