[U-Boot] [PATCH v9 08/16] regmap: Add raw read/write functions
Mario Six
mario.six at gdsys.cc
Fri Sep 28 07:27:32 UTC 2018
The regmap functions currently assume that all register map accesses
have a data width of 32 bits, but there are maps that have different
widths.
To rectify this, implement the regmap_raw_read and regmap_raw_write
functions from the Linux kernel API that specify the width of a desired
read or write operation on a regmap.
Implement the regmap_read and regmap_write functions using these raw
functions in a backwards-compatible manner.
Reviewed-by: Anatolij Gustschin <agust at denx.de>
Signed-off-by: Mario Six <mario.six at gdsys.cc>
---
v8 -> v9:
* Removed forgotten "fpgamap" in documentation
v7 -> v8:
No changes
v6 -> v7:
* Fixed wrong variable type in 64-bit read (u32 -> u64)
* Added 64-bit case in write function
v5 -> v6:
* Corrected format specifier
* Added support for 64-bit reads/writes
v4 -> v5:
No changes
v3 -> v4:
* Switched 'ranges[0] + offset' to 'ranges[0].start + offset'
* Explained the difference between the raw and non-raw read/write
functions better in the docs
v2 -> v3:
* Implement the "raw" functions from Linux instead of adding a size
parameter to the regmap_{read,write} functions
* Fixed style violation
* Improved error handling
v1 -> v2:
New in v2
---
drivers/core/regmap.c | 64 +++++++++++++++++++++++++++++++++++++++++++++------
include/regmap.h | 58 ++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 115 insertions(+), 7 deletions(-)
diff --git a/drivers/core/regmap.c b/drivers/core/regmap.c
index 154426269d9..1025099797f 100644
--- a/drivers/core/regmap.c
+++ b/drivers/core/regmap.c
@@ -188,22 +188,72 @@ int regmap_uninit(struct regmap *map)
return 0;
}
+int regmap_raw_read(struct regmap *map, uint offset, void *valp, size_t val_len)
+{
+ void *ptr;
+
+ ptr = map_physmem(map->ranges[0].start + offset, val_len, MAP_NOCACHE);
+
+ switch (val_len) {
+ case REGMAP_SIZE_8:
+ *((u8 *)valp) = in_8((u8 *)ptr);
+ break;
+ case REGMAP_SIZE_16:
+ *((u16 *)valp) = in_le16((u16 *)ptr);
+ break;
+ case REGMAP_SIZE_32:
+ *((u32 *)valp) = in_le32((u32 *)ptr);
+ break;
+#if defined(in_le64) && defined(readq)
+ case REGMAP_SIZE_64:
+ *((u64 *)valp) = in_le64((u64 *)ptr);
+ break;
+#endif
+ default:
+ debug("%s: regmap size %zu unknown\n", __func__, val_len);
+ return -EINVAL;
+ }
+ return 0;
+}
+
int regmap_read(struct regmap *map, uint offset, uint *valp)
{
- u32 *ptr = map_physmem(map->ranges[0].start + offset, 4, MAP_NOCACHE);
+ return regmap_raw_read(map, offset, valp, REGMAP_SIZE_32);
+}
- *valp = le32_to_cpu(readl(ptr));
+int regmap_raw_write(struct regmap *map, uint offset, const void *val,
+ size_t val_len)
+{
+ void *ptr;
+
+ ptr = map_physmem(map->ranges[0].start + offset, val_len, MAP_NOCACHE);
+
+ switch (val_len) {
+ case REGMAP_SIZE_8:
+ out_8((u8 *)ptr, *((u8 *)val));
+ break;
+ case REGMAP_SIZE_16:
+ out_le16((u16 *)ptr, *((u16 *)val));
+ break;
+ case REGMAP_SIZE_32:
+ out_le32((u32 *)ptr, *((u32 *)val));
+ break;
+#if defined(out_le64) && defined(writeq)
+ case REGMAP_SIZE_64:
+ out_le64((u64 *)ptr, *((u64 *)val));
+ break;
+#endif
+ default:
+ debug("%s: regmap size %zu unknown\n", __func__, val_len);
+ return -EINVAL;
+ }
return 0;
}
int regmap_write(struct regmap *map, uint offset, uint val)
{
- u32 *ptr = map_physmem(map->ranges[0].start + offset, 4, MAP_NOCACHE);
-
- writel(cpu_to_le32(val), ptr);
-
- return 0;
+ return regmap_raw_write(map, offset, &val, REGMAP_SIZE_32);
}
int regmap_update_bits(struct regmap *map, uint offset, uint mask, uint val)
diff --git a/include/regmap.h b/include/regmap.h
index 32f75e06f59..f23664e8ba1 100644
--- a/include/regmap.h
+++ b/include/regmap.h
@@ -8,6 +8,21 @@
#define __REGMAP_H
/**
+ * enum regmap_size_t - Access sizes for regmap reads and writes
+ *
+ * @REGMAP_SIZE_8: 8-bit read/write access size
+ * @REGMAP_SIZE_16: 16-bit read/write access size
+ * @REGMAP_SIZE_32: 32-bit read/write access size
+ * @REGMAP_SIZE_64: 64-bit read/write access size
+ */
+enum regmap_size_t {
+ REGMAP_SIZE_8 = 1,
+ REGMAP_SIZE_16 = 2,
+ REGMAP_SIZE_32 = 4,
+ REGMAP_SIZE_64 = 8,
+};
+
+/**
* struct regmap_range - a register map range
*
* @start: Start address
@@ -41,6 +56,10 @@ struct regmap {
* @offset: Offset in the regmap to write to
* @val: Data to write to the regmap at the specified offset
*
+ * Note that this function will only write values of 32 bit width to the
+ * regmap; if the size of data to be read is different, the regmap_raw_write
+ * function can be used.
+ *
* Return: 0 if OK, -ve on error
*/
int regmap_write(struct regmap *map, uint offset, uint val);
@@ -53,10 +72,49 @@ int regmap_write(struct regmap *map, uint offset, uint val);
* @valp: Pointer to the buffer to receive the data read from the regmap
* at the specified offset
*
+ * Note that this function will only read values of 32 bit width from the
+ * regmap; if the size of data to be read is different, the regmap_raw_read
+ * function can be used.
+ *
* Return: 0 if OK, -ve on error
*/
int regmap_read(struct regmap *map, uint offset, uint *valp);
+/**
+ * regmap_raw_write() - Write a value of specified length to a regmap
+ *
+ * @map: Regmap to write to
+ * @offset: Offset in the regmap to write to
+ * @val: Value to write to the regmap at the specified offset
+ * @val_len: Length of the data to be written to the regmap
+ *
+ * Note that this function will, as opposed to regmap_write, write data of
+ * arbitrary length to the regmap, and not just 32-bit values, and is thus a
+ * generalized version of regmap_write.
+ *
+ * Return: 0 if OK, -ve on error
+ */
+int regmap_raw_write(struct regmap *map, uint offset, const void *val,
+ size_t val_len);
+
+/**
+ * regmap_raw_read() - Read a value of specified length from a regmap
+ *
+ * @map: Regmap to read from
+ * @offset: Offset in the regmap to read from
+ * @valp: Pointer to the buffer to receive the data read from the regmap
+ * at the specified offset
+ * @val_len: Length of the data to be read from the regmap
+ *
+ * Note that this function will, as opposed to regmap_read, read data of
+ * arbitrary length from the regmap, and not just 32-bit values, and is thus a
+ * generalized version of regmap_read.
+ *
+ * Return: 0 if OK, -ve on error
+ */
+int regmap_raw_read(struct regmap *map, uint offset, void *valp,
+ size_t val_len);
+
#define regmap_write32(map, ptr, member, val) \
regmap_write(map, (uint32_t *)(ptr)->member - (uint32_t *)(ptr), val)
--
2.11.0
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