git.openwrt.org Git - openwrt/staging/xback.git/blob

   1 From 0074f3f2b1e43d3cedd97e47fb6980db6d2ba79e Mon Sep 17 00:00:00 2001
   2 From: Colin Foster <colin.foster@in-advantage.com>
   3 Date: Sun, 13 Mar 2022 15:45:24 -0700
   4 Subject: [PATCH 2/2] regmap: allow a defined reg_base to be added to every
   5  address
   6
   7 There's an inconsistency that arises when a register set can be accessed
   8 internally via MMIO, or externally via SPI. The VSC7514 chip allows both
   9 modes of operation. When internally accessed, the system utilizes __iomem,
  10 devm_ioremap_resource, and devm_regmap_init_mmio.
  11
  12 For SPI it isn't possible to utilize memory-mapped IO. To properly operate,
  13 the resource base must be added to the register before every operation.
  14
  15 Signed-off-by: Colin Foster <colin.foster@in-advantage.com>
  16 Link: https://lore.kernel.org/r/20220313224524.399947-3-colin.foster@in-advantage.com
  17 Signed-off-by: Mark Brown <broonie@kernel.org>
  18 ---
  19  drivers/base/regmap/internal.h | 1 +
  20  drivers/base/regmap/regmap.c   | 6 ++++++
  21  include/linux/regmap.h         | 3 +++
  22  3 files changed, 10 insertions(+)
  23
  24 --- a/drivers/base/regmap/internal.h
  25 +++ b/drivers/base/regmap/internal.h
  26 @@ -63,6 +63,7 @@ struct regmap {
  27         regmap_unlock unlock;
  28         void *lock_arg; /* This is passed to lock/unlock functions */
  29         gfp_t alloc_flags;
  30 +       unsigned int reg_base;
  31
  32         struct device *dev; /* Device we do I/O on */
  33         void *work_buf;     /* Scratch buffer used to format I/O */
  34 --- a/drivers/base/regmap/regmap.c
  35 +++ b/drivers/base/regmap/regmap.c
  36 @@ -821,6 +821,8 @@ struct regmap *__regmap_init(struct devi
  37         else
  38                 map->alloc_flags = GFP_KERNEL;
  39
  40 +       map->reg_base = config->reg_base;
  41 +
  42         map->format.reg_bytes = DIV_ROUND_UP(config->reg_bits, 8);
  43         map->format.pad_bytes = config->pad_bits / 8;
  44         map->format.reg_downshift = config->reg_downshift;
  45 @@ -1751,6 +1753,7 @@ static int _regmap_raw_write_impl(struct
  46                         return ret;
  47         }
  48
  49 +       reg += map->reg_base;
  50         reg >>= map->format.reg_downshift;
  51         map->format.format_reg(map->work_buf, reg, map->reg_shift);
  52         regmap_set_work_buf_flag_mask(map, map->format.reg_bytes,
  53 @@ -1922,6 +1925,7 @@ static int _regmap_bus_formatted_write(v
  54                         return ret;
  55         }
  56
  57 +       reg += map->reg_base;
  58         reg >>= map->format.reg_downshift;
  59         map->format.format_write(map, reg, val);
  60
  61 @@ -2363,6 +2367,7 @@ static int _regmap_raw_multi_reg_write(s
  62                 unsigned int reg = regs[i].reg;
  63                 unsigned int val = regs[i].def;
  64                 trace_regmap_hw_write_start(map, reg, 1);
  65 +               reg += map->reg_base;
  66                 reg >>= map->format.reg_downshift;
  67                 map->format.format_reg(u8, reg, map->reg_shift);
  68                 u8 += reg_bytes + pad_bytes;
  69 @@ -2689,6 +2694,7 @@ static int _regmap_raw_read(struct regma
  70                         return ret;
  71         }
  72
  73 +       reg += map->reg_base;
  74         reg >>= map->format.reg_downshift;
  75         map->format.format_reg(map->work_buf, reg, map->reg_shift);
  76         regmap_set_work_buf_flag_mask(map, map->format.reg_bytes,
  77 --- a/include/linux/regmap.h
  78 +++ b/include/linux/regmap.h
  79 @@ -239,6 +239,8 @@ typedef void (*regmap_unlock)(void *);
  80   *              used.
  81   * @reg_downshift: The number of bits to downshift the register before
  82   *                performing any operations.
  83 + * @reg_base: Value to be added to every register address before performing any
  84 + *           operation.
  85   * @pad_bits: Number of bits of padding between register and value.
  86   * @val_bits: Number of bits in a register value, mandatory.
  87   *
  88 @@ -369,6 +371,7 @@ struct regmap_config {
  89         int reg_bits;
  90         int reg_stride;
  91         int reg_downshift;
  92 +       unsigned int reg_base;
  93         int pad_bits;
  94         int val_bits;
  95