linux-sg2042/include/linux/regmap.h

148 lines
4.9 KiB
C

#ifndef __LINUX_REGMAP_H
#define __LINUX_REGMAP_H
/*
* Register map access API
*
* Copyright 2011 Wolfson Microelectronics plc
*
* Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/device.h>
#include <linux/list.h>
struct module;
struct i2c_client;
struct spi_device;
/* An enum of all the supported cache types */
enum regcache_type {
REGCACHE_NONE,
REGCACHE_INDEXED,
REGCACHE_RBTREE,
REGCACHE_LZO
};
/**
* Default value for a register. We use an array of structs rather
* than a simple array as many modern devices have very sparse
* register maps.
*
* @reg: Register address.
* @def: Register default value.
*/
struct reg_default {
unsigned int reg;
unsigned int def;
};
/**
* Configuration for the register map of a device.
*
* @reg_bits: Number of bits in a register address, mandatory.
* @val_bits: Number of bits in a register value, mandatory.
*
* @writeable_reg: Optional callback returning true if the register
* can be written to.
* @readable_reg: Optional callback returning true if the register
* can be read from.
* @volatile_reg: Optional callback returning true if the register
* value can't be cached.
* @precious_reg: Optional callback returning true if the rgister
* should not be read outside of a call from the driver
* (eg, a clear on read interrupt status register).
*
* @max_register: Optional, specifies the maximum valid register index.
* @reg_defaults: Power on reset values for registers (for use with
* register cache support).
* @num_reg_defaults: Number of elements in reg_defaults.
*
* @read_flag_mask: Mask to be set in the top byte of the register when doing
* a read.
* @write_flag_mask: Mask to be set in the top byte of the register when doing
* a write. If both read_flag_mask and write_flag_mask are
* empty the regmap_bus default masks are used.
*
* @cache_type: The actual cache type.
* @reg_defaults_raw: Power on reset values for registers (for use with
* register cache support).
* @num_reg_defaults_raw: Number of elements in reg_defaults_raw.
*/
struct regmap_config {
int reg_bits;
int val_bits;
bool (*writeable_reg)(struct device *dev, unsigned int reg);
bool (*readable_reg)(struct device *dev, unsigned int reg);
bool (*volatile_reg)(struct device *dev, unsigned int reg);
bool (*precious_reg)(struct device *dev, unsigned int reg);
unsigned int max_register;
struct reg_default *reg_defaults;
unsigned int num_reg_defaults;
enum regcache_type cache_type;
const void *reg_defaults_raw;
unsigned int num_reg_defaults_raw;
u8 read_flag_mask;
u8 write_flag_mask;
};
typedef int (*regmap_hw_write)(struct device *dev, const void *data,
size_t count);
typedef int (*regmap_hw_gather_write)(struct device *dev,
const void *reg, size_t reg_len,
const void *val, size_t val_len);
typedef int (*regmap_hw_read)(struct device *dev,
const void *reg_buf, size_t reg_size,
void *val_buf, size_t val_size);
/**
* Description of a hardware bus for the register map infrastructure.
*
* @write: Write operation.
* @gather_write: Write operation with split register/value, return -ENOTSUPP
* if not implemented on a given device.
* @read: Read operation. Data is returned in the buffer used to transmit
* data.
* @read_flag_mask: Mask to be set in the top byte of the register when doing
* a read.
*/
struct regmap_bus {
regmap_hw_write write;
regmap_hw_gather_write gather_write;
regmap_hw_read read;
u8 read_flag_mask;
};
struct regmap *regmap_init(struct device *dev,
const struct regmap_bus *bus,
const struct regmap_config *config);
struct regmap *regmap_init_i2c(struct i2c_client *i2c,
const struct regmap_config *config);
struct regmap *regmap_init_spi(struct spi_device *dev,
const struct regmap_config *config);
void regmap_exit(struct regmap *map);
int regmap_write(struct regmap *map, unsigned int reg, unsigned int val);
int regmap_raw_write(struct regmap *map, unsigned int reg,
const void *val, size_t val_len);
int regmap_read(struct regmap *map, unsigned int reg, unsigned int *val);
int regmap_raw_read(struct regmap *map, unsigned int reg,
void *val, size_t val_len);
int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val,
size_t val_count);
int regmap_update_bits(struct regmap *map, unsigned int reg,
unsigned int mask, unsigned int val);
int regcache_sync(struct regmap *map);
void regcache_cache_only(struct regmap *map, bool enable);
void regcache_cache_bypass(struct regmap *map, bool enable);
#endif