regmap: Add regmap_init_mem_range()

Right now, the base of a regmap can only be obtained from the device
tree. This makes it impossible for devices which calculate the base at
runtime to use a regmap. An example of such a device is the Cadence
Sierra PHY.

Allow creating a regmap with one range whose start and size can be
specified by the driver based on calculations at runtime.

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

diff --git a/drivers/core/regmap.c b/drivers/core/regmap.c
index 173ae80..a9087df 100644 (file)
--- a/drivers/core/regmap.c
+++ b/drivers/core/regmap.c
@@ -164,6 +164,33 @@ err:
        return ret;
 }
 
+int regmap_init_mem_range(ofnode node, ulong r_start, ulong r_size,
+                         struct regmap **mapp)
+{
+       struct regmap *map;
+       struct regmap_range *range;
+
+       map = regmap_alloc(1);
+       if (!map)
+               return -ENOMEM;
+
+       range = &map->ranges[0];
+       range->start = r_start;
+       range->size = r_size;
+
+       if (ofnode_read_bool(node, "little-endian"))
+               map->endianness = REGMAP_LITTLE_ENDIAN;
+       else if (ofnode_read_bool(node, "big-endian"))
+               map->endianness = REGMAP_BIG_ENDIAN;
+       else if (ofnode_read_bool(node, "native-endian"))
+               map->endianness = REGMAP_NATIVE_ENDIAN;
+       else /* Default: native endianness */
+               map->endianness = REGMAP_NATIVE_ENDIAN;
+
+       *mapp = map;
+       return 0;
+}
+
 int regmap_init_mem(ofnode node, struct regmap **mapp)
 {
        struct regmap_range *range;

diff --git a/include/regmap.h b/include/regmap.h
index e6c59df..7c8ad04 100644 (file)
--- a/include/regmap.h
+++ b/include/regmap.h
@@ -351,6 +351,25 @@ int regmap_init_mem_platdata(struct udevice *dev, fdt_val_t *reg, int count,
 int regmap_init_mem_index(ofnode node, struct regmap **mapp, int index);
 
 /**
+ * regmap_init_mem_range() - Set up a new memory region for ofnode with the
+ *                          specified range.
+ *
+ * @node:      The ofnode for the map.
+ * @r_start:   Start of the range.
+ * @r_size:    Size of the range.
+ * @mapp:      Returns allocated map.
+ *
+ * Return: 0 in success, -errno otherwise
+ *
+ * This creates a regmap with one range where instead of extracting the range
+ * from 'node', it is created based on the parameters specified. This is
+ * useful when a driver needs to calculate the base of the regmap at runtime,
+ * and can't specify it in device tree.
+ */
+int regmap_init_mem_range(ofnode node, ulong r_start, ulong r_size,
+                         struct regmap **mapp);
+
+/**
  * devm_regmap_init() - Initialise register map (device managed)
  *
  * @dev: Device that will be interacted with