mirror of
https://github.com/torvalds/linux.git
synced 2024-12-28 13:51:44 +00:00
e4a70e3e7d
Add support to STM HTS221 humidity + temperature sensor http://www.st.com/resource/en/datasheet/hts221.pdf - continuous mode support - i2c support - spi support - trigger mode support Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@st.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
126 lines
2.7 KiB
C
126 lines
2.7 KiB
C
/*
|
|
* STMicroelectronics hts221 spi driver
|
|
*
|
|
* Copyright 2016 STMicroelectronics Inc.
|
|
*
|
|
* Lorenzo Bianconi <lorenzo.bianconi@st.com>
|
|
*
|
|
* Licensed under the GPL-2.
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/spi/spi.h>
|
|
#include <linux/slab.h>
|
|
#include "hts221.h"
|
|
|
|
#define SENSORS_SPI_READ 0x80
|
|
#define SPI_AUTO_INCREMENT 0x40
|
|
|
|
static int hts221_spi_read(struct device *dev, u8 addr, int len, u8 *data)
|
|
{
|
|
int err;
|
|
struct spi_device *spi = to_spi_device(dev);
|
|
struct iio_dev *iio_dev = spi_get_drvdata(spi);
|
|
struct hts221_hw *hw = iio_priv(iio_dev);
|
|
|
|
struct spi_transfer xfers[] = {
|
|
{
|
|
.tx_buf = hw->tb.tx_buf,
|
|
.bits_per_word = 8,
|
|
.len = 1,
|
|
},
|
|
{
|
|
.rx_buf = hw->tb.rx_buf,
|
|
.bits_per_word = 8,
|
|
.len = len,
|
|
}
|
|
};
|
|
|
|
if (len > 1)
|
|
addr |= SPI_AUTO_INCREMENT;
|
|
hw->tb.tx_buf[0] = addr | SENSORS_SPI_READ;
|
|
|
|
err = spi_sync_transfer(spi, xfers, ARRAY_SIZE(xfers));
|
|
if (err < 0)
|
|
return err;
|
|
|
|
memcpy(data, hw->tb.rx_buf, len * sizeof(u8));
|
|
|
|
return len;
|
|
}
|
|
|
|
static int hts221_spi_write(struct device *dev, u8 addr, int len, u8 *data)
|
|
{
|
|
struct spi_device *spi = to_spi_device(dev);
|
|
struct iio_dev *iio_dev = spi_get_drvdata(spi);
|
|
struct hts221_hw *hw = iio_priv(iio_dev);
|
|
|
|
struct spi_transfer xfers = {
|
|
.tx_buf = hw->tb.tx_buf,
|
|
.bits_per_word = 8,
|
|
.len = len + 1,
|
|
};
|
|
|
|
if (len >= HTS221_TX_MAX_LENGTH)
|
|
return -ENOMEM;
|
|
|
|
if (len > 1)
|
|
addr |= SPI_AUTO_INCREMENT;
|
|
hw->tb.tx_buf[0] = addr;
|
|
memcpy(&hw->tb.tx_buf[1], data, len);
|
|
|
|
return spi_sync_transfer(spi, &xfers, 1);
|
|
}
|
|
|
|
static const struct hts221_transfer_function hts221_transfer_fn = {
|
|
.read = hts221_spi_read,
|
|
.write = hts221_spi_write,
|
|
};
|
|
|
|
static int hts221_spi_probe(struct spi_device *spi)
|
|
{
|
|
struct hts221_hw *hw;
|
|
struct iio_dev *iio_dev;
|
|
|
|
iio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*hw));
|
|
if (!iio_dev)
|
|
return -ENOMEM;
|
|
|
|
spi_set_drvdata(spi, iio_dev);
|
|
|
|
hw = iio_priv(iio_dev);
|
|
hw->name = spi->modalias;
|
|
hw->dev = &spi->dev;
|
|
hw->irq = spi->irq;
|
|
hw->tf = &hts221_transfer_fn;
|
|
|
|
return hts221_probe(iio_dev);
|
|
}
|
|
|
|
static const struct of_device_id hts221_spi_of_match[] = {
|
|
{ .compatible = "st,hts221", },
|
|
{},
|
|
};
|
|
MODULE_DEVICE_TABLE(of, hts221_spi_of_match);
|
|
|
|
static const struct spi_device_id hts221_spi_id_table[] = {
|
|
{ HTS221_DEV_NAME },
|
|
{},
|
|
};
|
|
MODULE_DEVICE_TABLE(spi, hts221_spi_id_table);
|
|
|
|
static struct spi_driver hts221_driver = {
|
|
.driver = {
|
|
.name = "hts221_spi",
|
|
.of_match_table = of_match_ptr(hts221_spi_of_match),
|
|
},
|
|
.probe = hts221_spi_probe,
|
|
.id_table = hts221_spi_id_table,
|
|
};
|
|
module_spi_driver(hts221_driver);
|
|
|
|
MODULE_AUTHOR("Lorenzo Bianconi <lorenzo.bianconi@st.com>");
|
|
MODULE_DESCRIPTION("STMicroelectronics hts221 spi driver");
|
|
MODULE_LICENSE("GPL v2");
|