drivers/core/regmap.c

   1 /*
   2  * Copyright (c) 2015 Google, Inc
   3  * Written by Simon Glass <sjg@chromium.org>
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 #include <common.h>
   9 #include <dm.h>
  10 #include <errno.h>
  11 #include <libfdt.h>
  12 #include <malloc.h>
  13 #include <mapmem.h>
  14 #include <regmap.h>
  15
  16 DECLARE_GLOBAL_DATA_PTR;
  17
  18 int regmap_init_mem(struct udevice *dev, struct regmap **mapp)
  19 {
  20         const void *blob = gd->fdt_blob;
  21         struct regmap_range *range;
  22         const fdt32_t *cell;
  23         struct regmap *map;
  24         int count;
  25         int addr_len, size_len, both_len;
  26         int parent;
  27         int len;
  28
  29         parent = dev->parent->of_offset;
  30         addr_len = fdt_address_cells(blob, parent);
  31         size_len = fdt_size_cells(blob, parent);
  32         both_len = addr_len + size_len;
  33
  34         cell = fdt_getprop(blob, dev->of_offset, "reg", &len);
  35         len /= sizeof(*cell);
  36         count = len / both_len;
  37         if (!cell || !count)
  38                 return -EINVAL;
  39
  40         map = malloc(sizeof(struct regmap));
  41         if (!map)
  42                 return -ENOMEM;
  43
  44         if (count <= 1) {
  45                 map->range = &map->base_range;
  46         } else {
  47                 map->range = malloc(count * sizeof(struct regmap_range));
  48                 if (!map->range) {
  49                         free(map);
  50                         return -ENOMEM;
  51                 }
  52         }
  53
  54         map->base = fdtdec_get_number(cell, addr_len);
  55         map->range_count = count;
  56
  57         for (range = map->range; count > 0;
  58              count--, cell += both_len, range++) {
  59                 range->start = fdtdec_get_number(cell, addr_len);
  60                 range->size = fdtdec_get_number(cell + addr_len, size_len);
  61         }
  62
  63         *mapp = map;
  64
  65         return 0;
  66 }
  67
  68 void *regmap_get_range(struct regmap *map, unsigned int range_num)
  69 {
  70         struct regmap_range *range;
  71
  72         if (range_num >= map->range_count)
  73                 return NULL;
  74         range = &map->range[range_num];
  75
  76         return map_sysmem(range->start, range->size);
  77 }
  78
  79 int regmap_uninit(struct regmap *map)
  80 {
  81         if (map->range_count > 1)
  82                 free(map->range);
  83         free(map);
  84
  85         return 0;
  86 }