linux/drivers/base/regmap/regcache-flat.c
Jan Dakinevich 0ec74ad3c1
regmap: rework ->max_register handling
When regmap consists of single register, 'regmap' subsystem is unable to
understand whether ->max_register is set or not, because in both cases it
is equal to zero. It leads to that the logic based on value of
->max_register doesn't work. For example using of REGCACHE_FLAT fails.

This patch introduces an extra parameter to regmap config, indicating
that zero value in ->max_register is authentic.

Signed-off-by: Jan Dakinevich <jan.dakinevich@salutedevices.com>
Link: https://lore.kernel.org/r/20240126200836.1829995-1-jan.dakinevich@salutedevices.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2024-02-05 14:32:35 +00:00

84 lines
1.8 KiB
C

// 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/device.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);
}
static int regcache_flat_init(struct regmap *map)
{
int i;
unsigned int *cache;
if (!map || map->reg_stride_order < 0 || !map->max_register_is_set)
return -EINVAL;
map->cache = kcalloc(regcache_flat_get_index(map, map->max_register)
+ 1, sizeof(unsigned int), GFP_KERNEL);
if (!map->cache)
return -ENOMEM;
cache = map->cache;
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[index] = map->reg_defaults[i].def;
}
return 0;
}
static int regcache_flat_exit(struct regmap *map)
{
kfree(map->cache);
map->cache = NULL;
return 0;
}
static int regcache_flat_read(struct regmap *map,
unsigned int reg, unsigned int *value)
{
unsigned int *cache = map->cache;
unsigned int index = regcache_flat_get_index(map, reg);
*value = cache[index];
return 0;
}
static int regcache_flat_write(struct regmap *map, unsigned int reg,
unsigned int value)
{
unsigned int *cache = map->cache;
unsigned int index = regcache_flat_get_index(map, reg);
cache[index] = value;
return 0;
}
struct regcache_ops regcache_flat_ops = {
.type = REGCACHE_FLAT,
.name = "flat",
.init = regcache_flat_init,
.exit = regcache_flat_exit,
.read = regcache_flat_read,
.write = regcache_flat_write,
};