target/linux/generic/backport-5.15/350-v5.18-regmap-add-configurable-downshift-for-addresses.patch

   1 From 86fc59ef818beb0e1945d17f8e734898baba7e4e Mon Sep 17 00:00:00 2001
   2 From: Colin Foster <colin.foster@in-advantage.com>
   3 Date: Sun, 13 Mar 2022 15:45:23 -0700
   4 Subject: [PATCH 1/2] regmap: add configurable downshift for addresses
   5
   6 Add an additional reg_downshift to be applied to register addresses before
   7 any register accesses. An example of a device that uses this is a VSC7514
   8 chip, which require each register address to be downshifted by two if the
   9 access is performed over a SPI bus.
  10
  11 Signed-off-by: Colin Foster <colin.foster@in-advantage.com>
  12 Link: https://lore.kernel.org/r/20220313224524.399947-2-colin.foster@in-advantage.com
  13 Signed-off-by: Mark Brown <broonie@kernel.org>
  14 ---
  15  drivers/base/regmap/internal.h | 1 +
  16  drivers/base/regmap/regmap.c   | 5 +++++
  17  include/linux/regmap.h         | 3 +++
  18  3 files changed, 9 insertions(+)
  19
  20 --- a/drivers/base/regmap/internal.h
  21 +++ b/drivers/base/regmap/internal.h
  22 @@ -31,6 +31,7 @@ struct regmap_format {
  23         size_t buf_size;
  24         size_t reg_bytes;
  25         size_t pad_bytes;
  26 +       size_t reg_downshift;
  27         size_t val_bytes;
  28         void (*format_write)(struct regmap *map,
  29                              unsigned int reg, unsigned int val);
  30 --- a/drivers/base/regmap/regmap.c
  31 +++ b/drivers/base/regmap/regmap.c
  32 @@ -823,6 +823,7 @@ struct regmap *__regmap_init(struct devi
  33
  34         map->format.reg_bytes = DIV_ROUND_UP(config->reg_bits, 8);
  35         map->format.pad_bytes = config->pad_bits / 8;
  36 +       map->format.reg_downshift = config->reg_downshift;
  37         map->format.val_bytes = DIV_ROUND_UP(config->val_bits, 8);
  38         map->format.buf_size = DIV_ROUND_UP(config->reg_bits +
  39                         config->val_bits + config->pad_bits, 8);
  40 @@ -1737,6 +1738,7 @@ static int _regmap_raw_write_impl(struct
  41                         return ret;
  42         }
  43
  44 +       reg >>= map->format.reg_downshift;
  45         map->format.format_reg(map->work_buf, reg, map->reg_shift);
  46         regmap_set_work_buf_flag_mask(map, map->format.reg_bytes,
  47                                       map->write_flag_mask);
  48 @@ -1907,6 +1909,7 @@ static int _regmap_bus_formatted_write(v
  49                         return ret;
  50         }
  51
  52 +       reg >>= map->format.reg_downshift;
  53         map->format.format_write(map, reg, val);
  54
  55         trace_regmap_hw_write_start(map, reg, 1);
  56 @@ -2348,6 +2351,7 @@ static int _regmap_raw_multi_reg_write(s
  57                 unsigned int reg = regs[i].reg;
  58                 unsigned int val = regs[i].def;
  59                 trace_regmap_hw_write_start(map, reg, 1);
  60 +               reg >>= map->format.reg_downshift;
  61                 map->format.format_reg(u8, reg, map->reg_shift);
  62                 u8 += reg_bytes + pad_bytes;
  63                 map->format.format_val(u8, val, 0);
  64 @@ -2675,6 +2679,7 @@ static int _regmap_raw_read(struct regma
  65                         return ret;
  66         }
  67
  68 +       reg >>= map->format.reg_downshift;
  69         map->format.format_reg(map->work_buf, reg, map->reg_shift);
  70         regmap_set_work_buf_flag_mask(map, map->format.reg_bytes,
  71                                       map->read_flag_mask);
  72 --- a/include/linux/regmap.h
  73 +++ b/include/linux/regmap.h
  74 @@ -237,6 +237,8 @@ typedef void (*regmap_unlock)(void *);
  75   * @reg_stride: The register address stride. Valid register addresses are a
  76   *              multiple of this value. If set to 0, a value of 1 will be
  77   *              used.
  78 + * @reg_downshift: The number of bits to downshift the register before
  79 + *                performing any operations.
  80   * @pad_bits: Number of bits of padding between register and value.
  81   * @val_bits: Number of bits in a register value, mandatory.
  82   *
  83 @@ -360,6 +362,7 @@ struct regmap_config {
  84
  85         int reg_bits;
  86         int reg_stride;
  87 +       int reg_downshift;
  88         int pad_bits;
  89         int val_bits;
  90