diff options
Diffstat (limited to 'drivers/iio/pressure/bmp280-spi.c')
-rw-r--r-- | drivers/iio/pressure/bmp280-spi.c | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/drivers/iio/pressure/bmp280-spi.c b/drivers/iio/pressure/bmp280-spi.c new file mode 100644 index 000000000000..17bc95586f9e --- /dev/null +++ b/drivers/iio/pressure/bmp280-spi.c @@ -0,0 +1,125 @@ +/* + * 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"); |