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		unsigned int reg = map->reg_defaults[i].reg;
42		unsigned int index = regcache_flat_get_index(map, reg);
43
44		cache[index] = map->reg_defaults[i].def;
45	}
46
47	return 0;
48}
49
50static int regcache_flat_exit(struct regmap *map)
51{
52	kfree(map->cache);
53	map->cache = NULL;
54
55	return 0;
56}
57
58static int regcache_flat_read(struct regmap *map,
59			      unsigned int reg, unsigned int *value)
60{
61	unsigned int *cache = map->cache;
62	unsigned int index = regcache_flat_get_index(map, reg);
63
64	*value = cache[index];
65
66	return 0;
67}
68
69static int regcache_flat_write(struct regmap *map, unsigned int reg,
70			       unsigned int value)
71{
72	unsigned int *cache = map->cache;
73	unsigned int index = regcache_flat_get_index(map, reg);
74
75	cache[index] = value;
76
77	return 0;
78}
79
80struct regcache_ops regcache_flat_ops = {
81	.type = REGCACHE_FLAT,
82	.name = "flat",
83	.init = regcache_flat_init,
84	.exit = regcache_flat_exit,
85	.read = regcache_flat_read,
86	.write = regcache_flat_write,
87};