LXR linux/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/device.h>
  14#include <linux/seq_file.h>
  15#include <linux/slab.h>
  16
  17#include "internal.h"
  18
  19static inline unsigned int regcache_flat_get_index(const struct regmap *map,
  20                                                   unsigned int reg)
  21{
  22        return regcache_get_index_by_order(map, reg);
  23}
  24
  25static int regcache_flat_init(struct regmap *map)
  26{
  27        int i;
  28        unsigned int *cache;
  29
  30        if (!map || map->reg_stride_order < 0 || !map->max_register)
  31                return -EINVAL;
  32
  33        map->cache = kcalloc(regcache_flat_get_index(map, map->max_register)
  34                             + 1, sizeof(unsigned int), GFP_KERNEL);
  35        if (!map->cache)
  36                return -ENOMEM;
  37
  38        cache = map->cache;
  39
  40        for (i = 0; i < map->num_reg_defaults; i++)
  41                cache[regcache_flat_get_index(map, map->reg_defaults[i].reg)] =
  42                                map->reg_defaults[i].def;
  43
  44        return 0;
  45}
  46
  47static int regcache_flat_exit(struct regmap *map)
  48{
  49        kfree(map->cache);
  50        map->cache = NULL;
  51
  52        return 0;
  53}
  54
  55static int regcache_flat_read(struct regmap *map,
  56                              unsigned int reg, unsigned int *value)
  57{
  58        unsigned int *cache = map->cache;
  59
  60        *value = cache[regcache_flat_get_index(map, reg)];
  61
  62        return 0;
  63}
  64
  65static int regcache_flat_write(struct regmap *map, unsigned int reg,
  66                               unsigned int value)
  67{
  68        unsigned int *cache = map->cache;
  69
  70        cache[regcache_flat_get_index(map, reg)] = value;
  71
  72        return 0;
  73}
  74
  75struct regcache_ops regcache_flat_ops = {
  76        .type = REGCACHE_FLAT,
  77        .name = "flat",
  78        .init = regcache_flat_init,
  79        .exit = regcache_flat_exit,
  80        .read = regcache_flat_read,
  81        .write = regcache_flat_write,
  82};
  83