内核3.1引入一套新的API regmap,目的是提取出关于I2C SPI irq等相关注册、使能以及读写的公共部分,以提高代码的可重用性,并且使得在使用如上内核基础组件时变得更为简单易用。
0 基础结构
- struct regmap_config {
- int reg_bits;
- int pad_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;
- const 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;
- };
1 初始化regmap
- regmap_init_i2c(struct i2c_client *i2c, struct regmap_config *config);
- regmap_init_spi(struct spi_device *spi, strcut regmap_config *config);
- regmap_add_irq_chip(struct regmap *map, int irq, int irq_flags, int irq_base, struct regmap_irq_chip *chip, struct regmap_irq_chip_data **data);
前两个是用来关联i2c或者spi设备和regmap_config的,第三个用来在关联后的regmap上注册 irq
2 使用regmap
在初始化好regmap之后,就可以调用regmap提供的read/write/update等操作了。
- regmap_write(struct regmap *map, int reg, int val);
- regmap_raw_write(struct regmap *map, int reg, void *val, size_t val_len);
- regmap_read(struct regmap *map, int reg, int *val);
- regmap_raw_read(struct regmap *map, int reg, void *val, size_t val_len);
- regmap_bulk_read(struct regmap *map, int reg, void *val, size_t val_count);
- regmap_update_bits(struct regmap *map, int reg, int mask, int val);
- regcache_cache_bypass(arizona->regmap, true);
3 释放regmap
- regmap_exit(struct regmap *map);
文章出处:http://blog.csdn.net/hellowxwworld/article/details/10737569
[转载]regmap使用介绍
原文:http://www.cnblogs.com/gesaint/p/3985798.html