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 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 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 47 static int regcache_flat_exit(struct regmap *map) 48 { 49 kfree(map->cache); 50 map->cache = NULL; 51 52 return 0; 53 } 54 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 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