151 lines
		
	
	
		
			3.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			151 lines
		
	
	
		
			3.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  * MS5611 pressure and temperature sensor driver (SPI bus)
 | |
|  *
 | |
|  * Copyright (c) Tomasz Duszynski <tduszyns@gmail.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/delay.h>
 | |
| #include <linux/module.h>
 | |
| #include <linux/spi/spi.h>
 | |
| #include <linux/of_device.h>
 | |
| 
 | |
| #include "ms5611.h"
 | |
| 
 | |
| static int ms5611_spi_reset(struct device *dev)
 | |
| {
 | |
| 	u8 cmd = MS5611_RESET;
 | |
| 	struct ms5611_state *st = iio_priv(dev_to_iio_dev(dev));
 | |
| 
 | |
| 	return spi_write_then_read(st->client, &cmd, 1, NULL, 0);
 | |
| }
 | |
| 
 | |
| static int ms5611_spi_read_prom_word(struct device *dev, int index, u16 *word)
 | |
| {
 | |
| 	int ret;
 | |
| 	struct ms5611_state *st = iio_priv(dev_to_iio_dev(dev));
 | |
| 
 | |
| 	ret = spi_w8r16be(st->client, MS5611_READ_PROM_WORD + (index << 1));
 | |
| 	if (ret < 0)
 | |
| 		return ret;
 | |
| 
 | |
| 	*word = ret;
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int ms5611_spi_read_adc(struct device *dev, s32 *val)
 | |
| {
 | |
| 	int ret;
 | |
| 	u8 buf[3] = { MS5611_READ_ADC };
 | |
| 	struct ms5611_state *st = iio_priv(dev_to_iio_dev(dev));
 | |
| 
 | |
| 	ret = spi_write_then_read(st->client, buf, 1, buf, 3);
 | |
| 	if (ret < 0)
 | |
| 		return ret;
 | |
| 
 | |
| 	*val = (buf[0] << 16) | (buf[1] << 8) | buf[2];
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int ms5611_spi_read_adc_temp_and_pressure(struct device *dev,
 | |
| 						 s32 *temp, s32 *pressure)
 | |
| {
 | |
| 	int ret;
 | |
| 	struct ms5611_state *st = iio_priv(dev_to_iio_dev(dev));
 | |
| 	const struct ms5611_osr *osr = st->temp_osr;
 | |
| 
 | |
| 	/*
 | |
| 	 * Warning: &osr->cmd MUST be aligned on a word boundary since used as
 | |
| 	 * 2nd argument (void*) of spi_write_then_read.
 | |
| 	 */
 | |
| 	ret = spi_write_then_read(st->client, &osr->cmd, 1, NULL, 0);
 | |
| 	if (ret < 0)
 | |
| 		return ret;
 | |
| 
 | |
| 	usleep_range(osr->conv_usec, osr->conv_usec + (osr->conv_usec / 10UL));
 | |
| 	ret = ms5611_spi_read_adc(dev, temp);
 | |
| 	if (ret < 0)
 | |
| 		return ret;
 | |
| 
 | |
| 	osr = st->pressure_osr;
 | |
| 	ret = spi_write_then_read(st->client, &osr->cmd, 1, NULL, 0);
 | |
| 	if (ret < 0)
 | |
| 		return ret;
 | |
| 
 | |
| 	usleep_range(osr->conv_usec, osr->conv_usec + (osr->conv_usec / 10UL));
 | |
| 	return ms5611_spi_read_adc(dev, pressure);
 | |
| }
 | |
| 
 | |
| static int ms5611_spi_probe(struct spi_device *spi)
 | |
| {
 | |
| 	int ret;
 | |
| 	struct ms5611_state *st;
 | |
| 	struct iio_dev *indio_dev;
 | |
| 
 | |
| 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
 | |
| 	if (!indio_dev)
 | |
| 		return -ENOMEM;
 | |
| 
 | |
| 	spi_set_drvdata(spi, indio_dev);
 | |
| 
 | |
| 	spi->mode = SPI_MODE_0;
 | |
| 	spi->max_speed_hz = 20000000;
 | |
| 	spi->bits_per_word = 8;
 | |
| 	ret = spi_setup(spi);
 | |
| 	if (ret < 0)
 | |
| 		return ret;
 | |
| 
 | |
| 	st = iio_priv(indio_dev);
 | |
| 	st->reset = ms5611_spi_reset;
 | |
| 	st->read_prom_word = ms5611_spi_read_prom_word;
 | |
| 	st->read_adc_temp_and_pressure = ms5611_spi_read_adc_temp_and_pressure;
 | |
| 	st->client = spi;
 | |
| 
 | |
| 	return ms5611_probe(indio_dev, &spi->dev, spi_get_device_id(spi)->name,
 | |
| 			    spi_get_device_id(spi)->driver_data);
 | |
| }
 | |
| 
 | |
| static int ms5611_spi_remove(struct spi_device *spi)
 | |
| {
 | |
| 	return ms5611_remove(spi_get_drvdata(spi));
 | |
| }
 | |
| 
 | |
| #if defined(CONFIG_OF)
 | |
| static const struct of_device_id ms5611_spi_matches[] = {
 | |
| 	{ .compatible = "meas,ms5611" },
 | |
| 	{ .compatible = "ms5611" },
 | |
| 	{ .compatible = "meas,ms5607" },
 | |
| 	{ .compatible = "ms5607" },
 | |
| 	{ }
 | |
| };
 | |
| MODULE_DEVICE_TABLE(of, ms5611_spi_matches);
 | |
| #endif
 | |
| 
 | |
| static const struct spi_device_id ms5611_id[] = {
 | |
| 	{ "ms5611", MS5611 },
 | |
| 	{ "ms5607", MS5607 },
 | |
| 	{ }
 | |
| };
 | |
| MODULE_DEVICE_TABLE(spi, ms5611_id);
 | |
| 
 | |
| static struct spi_driver ms5611_driver = {
 | |
| 	.driver = {
 | |
| 		.name = "ms5611",
 | |
| 		.of_match_table = of_match_ptr(ms5611_spi_matches)
 | |
| 	},
 | |
| 	.id_table = ms5611_id,
 | |
| 	.probe = ms5611_spi_probe,
 | |
| 	.remove = ms5611_spi_remove,
 | |
| };
 | |
| module_spi_driver(ms5611_driver);
 | |
| 
 | |
| MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>");
 | |
| MODULE_DESCRIPTION("MS5611 spi driver");
 | |
| MODULE_LICENSE("GPL v2");
 | 
