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regmap: allow a defined reg_base to be added to every address 

There's an inconsistency that arises when a register set can be accessed
internally via MMIO, or externally via SPI. The VSC7514 chip allows both
modes of operation. When internally accessed, the system utilizes __iomem,
devm_ioremap_resource, and devm_regmap_init_mmio.

For SPI it isn't possible to utilize memory-mapped IO. To properly operate,
the resource base must be added to the register before every operation.

Signed-off-by: Colin Foster <colin.foster@in-advantage.com>
Link: https://lore.kernel.org/r/20220313224524.399947-3-colin.foster@in-advantage.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Colin Foster 2022-03-13 15:45:24 -07:00 committed by Mark Brown
parent 86fc59ef81
commit 0074f3f2b1
No known key found for this signature in database
GPG Key ID: 24D68B725D5487D0
3 changed files with 10 additions and 0 deletions
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1
drivers/base/regmap/internal.h
View File

@ -63,6 +63,7 @@ struct regmap {
regmap_unlock unlock;
void *lock_arg; /* This is passed to lock/unlock functions */
gfp_t alloc_flags;
unsigned int reg_base;
struct device *dev; /* Device we do I/O on */
void *work_buf; /* Scratch buffer used to format I/O */

6
drivers/base/regmap/regmap.c
View File

@ -821,6 +821,8 @@ struct regmap *__regmap_init(struct device *dev,
else
map->alloc_flags = GFP_KERNEL;
map->reg_base = config->reg_base;
map->format.reg_bytes = DIV_ROUND_UP(config->reg_bits, 8);
map->format.pad_bytes = config->pad_bits / 8;
map->format.reg_downshift = config->reg_downshift;
@ -1736,6 +1738,7 @@ static int _regmap_raw_write_impl(struct regmap *map, unsigned int reg,
return ret;
}
reg += map->reg_base;
reg >>= map->format.reg_downshift;
map->format.format_reg(map->work_buf, reg, map->reg_shift);
regmap_set_work_buf_flag_mask(map, map->format.reg_bytes,
@ -1907,6 +1910,7 @@ static int _regmap_bus_formatted_write(void *context, unsigned int reg,
return ret;
}
reg += map->reg_base;
reg >>= map->format.reg_downshift;
map->format.format_write(map, reg, val);
@ -2349,6 +2353,7 @@ static int _regmap_raw_multi_reg_write(struct regmap *map,
unsigned int reg = regs[i].reg;
unsigned int val = regs[i].def;
trace_regmap_hw_write_start(map, reg, 1);
reg += map->reg_base;
reg >>= map->format.reg_downshift;
map->format.format_reg(u8, reg, map->reg_shift);
u8 += reg_bytes + pad_bytes;
@ -2677,6 +2682,7 @@ static int _regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
return ret;
}
reg += map->reg_base;
reg >>= map->format.reg_downshift;
map->format.format_reg(map->work_buf, reg, map->reg_shift);
regmap_set_work_buf_flag_mask(map, map->format.reg_bytes,

3
include/linux/regmap.h
View File

@ -239,6 +239,8 @@ typedef void (*regmap_unlock)(void *);
* used.
* @reg_downshift: The number of bits to downshift the register before
* performing any operations.
* @reg_base: Value to be added to every register address before performing any
* operation.
* @pad_bits: Number of bits of padding between register and value.
* @val_bits: Number of bits in a register value, mandatory.
*
@ -363,6 +365,7 @@ struct regmap_config {
int reg_bits;
int reg_stride;
int reg_downshift;
unsigned int reg_base;
int pad_bits;
int val_bits;