// SPDX-License-Identifier: GPL-2.0//// Register cache access API - flat caching support//// Copyright 2012 Wolfson Microelectronics plc//// Author: Mark Brown <broonie@opensource.wolfsonmicro.com> #include <linux/bitmap.h>#include <linux/bitops.h>#include <linux/device.h>#include <linux/limits.h>#include <linux/overflow.h>#include <linux/seq_file.h>#include <linux/slab.h> #include "internal.h" static inline unsigned int regcache_flat_get_index(const struct regmap *map,						   unsigned int reg){	return regcache_get_index_by_order(map, reg);} struct regcache_flat_data {	unsigned long *valid;	unsigned int data[];}; static int regcache_flat_init(struct regmap *map){	unsigned int cache_size;	struct regcache_flat_data *cache; 	if (!map || map->reg_stride_order < 0 || !map->max_register_is_set)		return -EINVAL; 	cache_size = regcache_flat_get_index(map, map->max_register) + 1;	cache = kzalloc_flex(*cache, data, cache_size, map->alloc_flags);	if (!cache)		return -ENOMEM; 	cache->valid = bitmap_zalloc(cache_size, map->alloc_flags);	if (!cache->valid)		goto err_free; 	map->cache = cache; 	return 0; err_free:	kfree(cache);	return -ENOMEM;} static int regcache_flat_exit(struct regmap *map){	struct regcache_flat_data *cache = map->cache; 	if (cache)		bitmap_free(cache->valid); 	kfree(cache);	map->cache = NULL; 	return 0;} static int regcache_flat_populate(struct regmap *map){	struct regcache_flat_data *cache = map->cache;	unsigned int i; 	for (i = 0; i < map->num_reg_defaults; i++) {		unsigned int reg = map->reg_defaults[i].reg;		unsigned int index = regcache_flat_get_index(map, reg); 		cache->data[index] = map->reg_defaults[i].def;		__set_bit(index, cache->valid);	} 	if (map->reg_default_cb) {		dev_dbg(map->dev,			"Populating regcache_flat using reg_default_cb callback\n"); 		for (i = 0; i <= map->max_register; i += map->reg_stride) {			unsigned int index = regcache_flat_get_index(map, i);			unsigned int value; 			if (test_bit(index, cache->valid))				continue; 			if (map->reg_default_cb(map->dev, i, &value))				continue; 			cache->data[index] = value;			__set_bit(index, cache->valid);		}	} 	return 0;} static int regcache_flat_read(struct regmap *map,			      unsigned int reg, unsigned int *value){	struct regcache_flat_data *cache = map->cache;	unsigned int index = regcache_flat_get_index(map, reg); 	/* legacy behavior: ignore validity, but warn the user */	if (unlikely(!test_bit(index, cache->valid)))		dev_warn_once(map->dev,			"using zero-initialized flat cache, this may cause unexpected behavior"); 	*value = cache->data[index]; 	return 0;} static int regcache_flat_sparse_read(struct regmap *map,				     unsigned int reg, unsigned int *value){	struct regcache_flat_data *cache = map->cache;	unsigned int index = regcache_flat_get_index(map, reg); 	if (unlikely(!test_bit(index, cache->valid)))		return -ENOENT; 	*value = cache->data[index]; 	return 0;} static int regcache_flat_write(struct regmap *map, unsigned int reg,			       unsigned int value){	struct regcache_flat_data *cache = map->cache;	unsigned int index = regcache_flat_get_index(map, reg); 	cache->data[index] = value;	__set_bit(index, cache->valid); 	return 0;} static int regcache_flat_drop(struct regmap *map, unsigned int min,			      unsigned int max){	struct regcache_flat_data *cache = map->cache;	unsigned int bitmap_min = regcache_flat_get_index(map, min);	unsigned int bitmap_max = regcache_flat_get_index(map, max); 	bitmap_clear(cache->valid, bitmap_min, bitmap_max + 1 - bitmap_min); 	return 0;} struct regcache_ops regcache_flat_ops = {	.type = REGCACHE_FLAT,	.name = "flat",	.init = regcache_flat_init,	.exit = regcache_flat_exit,	.populate = regcache_flat_populate,	.read = regcache_flat_read,	.write = regcache_flat_write,}; struct regcache_ops regcache_flat_sparse_ops = {	.type = REGCACHE_FLAT_S,	.name = "flat-sparse",	.init = regcache_flat_init,	.exit = regcache_flat_exit,	.populate = regcache_flat_populate,	.read = regcache_flat_sparse_read,	.write = regcache_flat_write,	.drop = regcache_flat_drop,};