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1// SPDX-License-Identifier: GPL-2.02/*3 * MS5611 pressure and temperature sensor driver (SPI bus)4 *5 * Copyright (c) Tomasz Duszynski <tduszyns@gmail.com>6 *7 */8 9#include <linux/delay.h>10#include <linux/module.h>11#include <linux/spi/spi.h>12#include <linux/mod_devicetable.h>13 14#include <linux/unaligned.h>15 16#include "ms5611.h"17 18static int ms5611_spi_reset(struct ms5611_state *st)19{20 u8 cmd = MS5611_RESET;21 22 return spi_write_then_read(st->client, &cmd, 1, NULL, 0);23}24 25static int ms5611_spi_read_prom_word(struct ms5611_state *st, int index,26 u16 *word)27{28 int ret;29 30 ret = spi_w8r16be(st->client, MS5611_READ_PROM_WORD + (index << 1));31 if (ret < 0)32 return ret;33 34 *word = ret;35 36 return 0;37}38 39static int ms5611_spi_read_adc(struct ms5611_state *st, s32 *val)40{41 int ret;42 u8 buf[3] = { MS5611_READ_ADC };43 44 ret = spi_write_then_read(st->client, buf, 1, buf, 3);45 if (ret < 0)46 return ret;47 48 *val = get_unaligned_be24(&buf[0]);49 50 return 0;51}52 53static int ms5611_spi_read_adc_temp_and_pressure(struct ms5611_state *st,54 s32 *temp, s32 *pressure)55{56 int ret;57 const struct ms5611_osr *osr = st->temp_osr;58 59 /*60 * Warning: &osr->cmd MUST be aligned on a word boundary since used as61 * 2nd argument (void*) of spi_write_then_read.62 */63 ret = spi_write_then_read(st->client, &osr->cmd, 1, NULL, 0);64 if (ret < 0)65 return ret;66 67 usleep_range(osr->conv_usec, osr->conv_usec + (osr->conv_usec / 10UL));68 ret = ms5611_spi_read_adc(st, temp);69 if (ret < 0)70 return ret;71 72 osr = st->pressure_osr;73 ret = spi_write_then_read(st->client, &osr->cmd, 1, NULL, 0);74 if (ret < 0)75 return ret;76 77 usleep_range(osr->conv_usec, osr->conv_usec + (osr->conv_usec / 10UL));78 return ms5611_spi_read_adc(st, pressure);79}80 81static int ms5611_spi_probe(struct spi_device *spi)82{83 int ret;84 struct ms5611_state *st;85 struct iio_dev *indio_dev;86 87 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));88 if (!indio_dev)89 return -ENOMEM;90 91 spi_set_drvdata(spi, indio_dev);92 93 spi->mode = SPI_MODE_0;94 spi->max_speed_hz = min(spi->max_speed_hz, 20000000U);95 spi->bits_per_word = 8;96 ret = spi_setup(spi);97 if (ret < 0)98 return ret;99 100 st = iio_priv(indio_dev);101 st->reset = ms5611_spi_reset;102 st->read_prom_word = ms5611_spi_read_prom_word;103 st->read_adc_temp_and_pressure = ms5611_spi_read_adc_temp_and_pressure;104 st->client = spi;105 106 return ms5611_probe(indio_dev, &spi->dev, spi_get_device_id(spi)->name,107 spi_get_device_id(spi)->driver_data);108}109 110static const struct of_device_id ms5611_spi_matches[] = {111 { .compatible = "meas,ms5611" },112 { .compatible = "meas,ms5607" },113 { }114};115MODULE_DEVICE_TABLE(of, ms5611_spi_matches);116 117static const struct spi_device_id ms5611_id[] = {118 { "ms5611", MS5611 },119 { "ms5607", MS5607 },120 { }121};122MODULE_DEVICE_TABLE(spi, ms5611_id);123 124static struct spi_driver ms5611_driver = {125 .driver = {126 .name = "ms5611",127 .of_match_table = ms5611_spi_matches128 },129 .id_table = ms5611_id,130 .probe = ms5611_spi_probe,131};132module_spi_driver(ms5611_driver);133 134MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>");135MODULE_DESCRIPTION("MS5611 spi driver");136MODULE_LICENSE("GPL v2");137MODULE_IMPORT_NS(IIO_MS5611);138