tegrakernel/kernel/kernel-4.9/drivers/iio/pressure/bmp280-spi.c

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2022-02-16 09:13:02 -06:00
/*
* SPI interface for the BMP280 driver
*
* Inspired by the older BMP085 driver drivers/misc/bmp085-spi.c
*/
#include <linux/module.h>
#include <linux/spi/spi.h>
#include <linux/err.h>
#include <linux/regmap.h>
#include "bmp280.h"
static int bmp280_regmap_spi_write(void *context, const void *data,
size_t count)
{
struct device *dev = context;
struct spi_device *spi = to_spi_device(dev);
u8 buf[2];
memcpy(buf, data, 2);
/*
* The SPI register address (= full register address without bit 7) and
* the write command (bit7 = RW = '0')
*/
buf[0] &= ~0x80;
return spi_write_then_read(spi, buf, 2, NULL, 0);
}
static int bmp280_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 bmp280_regmap_bus = {
.write = bmp280_regmap_spi_write,
.read = bmp280_regmap_spi_read,
.reg_format_endian_default = REGMAP_ENDIAN_BIG,
.val_format_endian_default = REGMAP_ENDIAN_BIG,
};
static int bmp280_spi_probe(struct spi_device *spi)
{
const struct spi_device_id *id = spi_get_device_id(spi);
struct regmap *regmap;
const struct regmap_config *regmap_config;
int ret;
spi->bits_per_word = 8;
ret = spi_setup(spi);
if (ret < 0) {
dev_err(&spi->dev, "spi_setup failed!\n");
return ret;
}
switch (id->driver_data) {
case BMP180_CHIP_ID:
regmap_config = &bmp180_regmap_config;
break;
case BMP280_CHIP_ID:
case BME280_CHIP_ID:
regmap_config = &bmp280_regmap_config;
break;
default:
return -EINVAL;
}
regmap = devm_regmap_init(&spi->dev,
&bmp280_regmap_bus,
&spi->dev,
regmap_config);
if (IS_ERR(regmap)) {
dev_err(&spi->dev, "failed to allocate register map\n");
return PTR_ERR(regmap);
}
return bmp280_common_probe(&spi->dev,
regmap,
id->driver_data,
id->name,
spi->irq);
}
static int bmp280_spi_remove(struct spi_device *spi)
{
return bmp280_common_remove(&spi->dev);
}
static const struct of_device_id bmp280_of_spi_match[] = {
{ .compatible = "bosch,bmp085", },
{ .compatible = "bosch,bmp180", },
{ .compatible = "bosch,bmp181", },
{ .compatible = "bosch,bmp280", },
{ .compatible = "bosch,bme280", },
{ },
};
MODULE_DEVICE_TABLE(of, bmp280_of_spi_match);
static const struct spi_device_id bmp280_spi_id[] = {
{ "bmp180", BMP180_CHIP_ID },
{ "bmp181", BMP180_CHIP_ID },
{ "bmp280", BMP280_CHIP_ID },
{ "bme280", BME280_CHIP_ID },
{ }
};
MODULE_DEVICE_TABLE(spi, bmp280_spi_id);
static struct spi_driver bmp280_spi_driver = {
.driver = {
.name = "bmp280",
.of_match_table = bmp280_of_spi_match,
.pm = &bmp280_dev_pm_ops,
},
.id_table = bmp280_spi_id,
.probe = bmp280_spi_probe,
.remove = bmp280_spi_remove,
};
module_spi_driver(bmp280_spi_driver);
MODULE_DESCRIPTION("BMP280 SPI bus driver");
MODULE_LICENSE("GPL");