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
regcache_flat_get_index(const struct regmap * map,unsigned int reg)19 static 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
regcache_flat_init(struct regmap * map)25 static 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
regcache_flat_exit(struct regmap * map)47 static int regcache_flat_exit(struct regmap *map)
48 {
49 kfree(map->cache);
50 map->cache = NULL;
51
52 return 0;
53 }
54
regcache_flat_read(struct regmap * map,unsigned int reg,unsigned int * value)55 static 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
regcache_flat_write(struct regmap * map,unsigned int reg,unsigned int value)65 static 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
75 struct 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