drivers/base/regmap/regcache-flat.c

   1 /*
   2  * Register cache access API - flat caching support
   3  *
   4  * Copyright 2012 Wolfson Microelectronics plc
   5  *
   6  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/slab.h>
  14 #include <linux/device.h>
  15 #include <linux/seq_file.h>
  16
  17 #include "internal.h"
  18
  19 static int regcache_flat_init(struct regmap *map)
  20 {
  21         int i;
  22         unsigned int *cache;
  23
  24         map->cache = kzalloc(sizeof(unsigned int) * (map->max_register + 1),
  25                              GFP_KERNEL);
  26         if (!map->cache)
  27                 return -ENOMEM;
  28
  29         cache = map->cache;
  30
  31         for (i = 0; i < map->num_reg_defaults; i++)
  32                 cache[map->reg_defaults[i].reg] = map->reg_defaults[i].def;
  33
  34         return 0;
  35 }
  36
  37 static int regcache_flat_exit(struct regmap *map)
  38 {
  39         kfree(map->cache);
  40         map->cache = NULL;
  41
  42         return 0;
  43 }
  44
  45 static int regcache_flat_read(struct regmap *map,
  46                               unsigned int reg, unsigned int *value)
  47 {
  48         unsigned int *cache = map->cache;
  49
  50         *value = cache[reg];
  51
  52         return 0;
  53 }
  54
  55 static int regcache_flat_write(struct regmap *map, unsigned int reg,
  56                                unsigned int value)
  57 {
  58         unsigned int *cache = map->cache;
  59
  60         cache[reg] = value;
  61
  62         return 0;
  63 }
  64
  65 struct regcache_ops regcache_flat_ops = {
  66         .type = REGCACHE_FLAT,
  67         .name = "flat",
  68         .init = regcache_flat_init,
  69         .exit = regcache_flat_exit,
  70         .read = regcache_flat_read,
  71         .write = regcache_flat_write,
  72 };