linux/drivers/base/regmap/regmap-spi.c
Stephen Warren 0135bbcc7a regmap: introduce explicit bus_context for bus callbacks
The only context needed by I2C and SPI bus definitions is the device
itself; this can be converted to an i2c_client or spi_device in order
to perform IO on the device. However, other bus types may need more
context in order to perform IO. Enable this by having regmap_init accept
a bus_context parameter, and pass this to all bus callbacks. The
existing callbacks simply pass the struct device here. Future bus types
may pass something else.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-06 10:47:34 +01:00

93 lines
2.5 KiB
C

/*
* Register map access API - SPI support
*
* 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/regmap.h>
#include <linux/spi/spi.h>
#include <linux/init.h>
#include <linux/module.h>
static int regmap_spi_write(void *context, const void *data, size_t count)
{
struct device *dev = context;
struct spi_device *spi = to_spi_device(dev);
return spi_write(spi, data, count);
}
static int regmap_spi_gather_write(void *context,
const void *reg, size_t reg_len,
const void *val, size_t val_len)
{
struct device *dev = context;
struct spi_device *spi = to_spi_device(dev);
struct spi_message m;
struct spi_transfer t[2] = { { .tx_buf = reg, .len = reg_len, },
{ .tx_buf = val, .len = val_len, }, };
spi_message_init(&m);
spi_message_add_tail(&t[0], &m);
spi_message_add_tail(&t[1], &m);
return spi_sync(spi, &m);
}
static int regmap_spi_read(void *context,
const void *reg, size_t reg_size,
void *val, size_t val_size)
{
struct device *dev = context;
struct spi_device *spi = to_spi_device(dev);
return spi_write_then_read(spi, reg, reg_size, val, val_size);
}
static struct regmap_bus regmap_spi = {
.write = regmap_spi_write,
.gather_write = regmap_spi_gather_write,
.read = regmap_spi_read,
.read_flag_mask = 0x80,
};
/**
* regmap_init_spi(): Initialise register map
*
* @spi: Device that will be interacted with
* @config: Configuration for register map
*
* The return value will be an ERR_PTR() on error or a valid pointer to
* a struct regmap.
*/
struct regmap *regmap_init_spi(struct spi_device *spi,
const struct regmap_config *config)
{
return regmap_init(&spi->dev, &regmap_spi, &spi->dev, config);
}
EXPORT_SYMBOL_GPL(regmap_init_spi);
/**
* devm_regmap_init_spi(): Initialise register map
*
* @spi: Device that will be interacted with
* @config: Configuration for register map
*
* The return value will be an ERR_PTR() on error or a valid pointer
* to a struct regmap. The map will be automatically freed by the
* device management code.
*/
struct regmap *devm_regmap_init_spi(struct spi_device *spi,
const struct regmap_config *config)
{
return devm_regmap_init(&spi->dev, &regmap_spi, &spi->dev, config);
}
EXPORT_SYMBOL_GPL(devm_regmap_init_spi);
MODULE_LICENSE("GPL");