From 86fc59ef818beb0e1945d17f8e734898baba7e4e Mon Sep 17 00:00:00 2001 From: Colin Foster Date: Sun, 13 Mar 2022 15:45:23 -0700 Subject: [PATCH 1/2] 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: Colin Foster Link: https://lore.kernel.org/r/20220313224524.399947-2-colin.foster@in-advantage.com Signed-off-by: Mark Brown --- drivers/base/regmap/internal.h | 1 + drivers/base/regmap/regmap.c | 5 +++++ include/linux/regmap.h | 3 +++ 3 files changed, 9 insertions(+) --- a/drivers/base/regmap/internal.h +++ b/drivers/base/regmap/internal.h @@ -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); --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -823,6 +823,7 @@ struct regmap *__regmap_init(struct devi 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); @@ -1737,6 +1738,7 @@ static int _regmap_raw_write_impl(struct 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); @@ -1907,6 +1909,7 @@ static int _regmap_bus_formatted_write(v return ret; } + reg >>= map->format.reg_downshift; map->format.format_write(map, reg, val); trace_regmap_hw_write_start(map, reg, 1); @@ -2348,6 +2351,7 @@ static int _regmap_raw_multi_reg_write(s 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); @@ -2675,6 +2679,7 @@ static int _regmap_raw_read(struct regma 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); --- a/include/linux/regmap.h +++ b/include/linux/regmap.h @@ -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;