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 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 }; 73