Unverified Commit 86fc59ef authored by Colin Foster's avatar Colin Foster Committed by Mark Brown
Browse files

regmap: add configurable downshift for addresses 



Add an additional reg_downshift to be applied to register addresses before
any register accesses. An example of a device that uses this is a VSC7514
chip, which require each register address to be downshifted by two if the
access is performed over a SPI bus.

Signed-off-by: default avatarColin Foster <colin.foster@in-advantage.com>
Link: https://lore.kernel.org/r/20220313224524.399947-2-colin.foster@in-advantage.com


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent 2d232978

drivers/base/regmap/internal.h

+1 −0
Original line number Diff line number Diff line
@@ -31,6 +31,7 @@ struct regmap_format { 
	size_t buf_size;

	size_t reg_bytes;

	size_t pad_bytes;

	size_t reg_downshift;

	size_t val_bytes;

	void (*format_write)(struct regmap *map,

			     unsigned int reg, unsigned int val);

drivers/base/regmap/regmap.c

+5 −0
Original line number Diff line number Diff line
@@ -823,6 +823,7 @@ struct regmap *__regmap_init(struct device *dev, 


	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;

	map->format.val_bytes = DIV_ROUND_UP(config->val_bits, 8);

	map->format.buf_size = DIV_ROUND_UP(config->reg_bits +

			config->val_bits + config->pad_bits, 8);
@@ -1735,6 +1736,7 @@ static int _regmap_raw_write_impl(struct regmap *map, unsigned int reg, 
			return ret;

	}



	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,

				      map->write_flag_mask);
@@ -1905,6 +1907,7 @@ static int _regmap_bus_formatted_write(void *context, unsigned int reg, 
			return ret;

	}



	reg >>= map->format.reg_downshift;

	map->format.format_write(map, reg, val);



	trace_regmap_hw_write_start(map, reg, 1);
@@ -2346,6 +2349,7 @@ 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->format.reg_downshift;

		map->format.format_reg(u8, reg, map->reg_shift);

		u8 += reg_bytes + pad_bytes;

		map->format.format_val(u8, val, 0);
@@ -2673,6 +2677,7 @@ static int _regmap_raw_read(struct regmap *map, unsigned int reg, void *val, 
			return ret;

	}



	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,

				      map->read_flag_mask);

include/linux/regmap.h

+3 −0
Original line number Diff line number Diff line
@@ -237,6 +237,8 @@ typedef void (*regmap_unlock)(void *); 
 * @reg_stride: The register address stride. Valid register addresses are a

 *              multiple of this value. If set to 0, a value of 1 will be

 *              used.

 * @reg_downshift: The number of bits to downshift the register before

 *		   performing any operations.

 * @pad_bits: Number of bits of padding between register and value.

 * @val_bits: Number of bits in a register value, mandatory.

 *
@@ -360,6 +362,7 @@ struct regmap_config { 


	int reg_bits;

	int reg_stride;

	int reg_downshift;

	int pad_bits;

	int val_bits;