cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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ms5611_spi.c (3232B)

      1// SPDX-License-Identifier: GPL-2.0
      2/*
      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 <asm/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 as
     61	 * 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 = 20000000;
     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 void ms5611_spi_remove(struct spi_device *spi)
    111{
    112	ms5611_remove(spi_get_drvdata(spi));
    113}
    114
    115static const struct of_device_id ms5611_spi_matches[] = {
    116	{ .compatible = "meas,ms5611" },
    117	{ .compatible = "meas,ms5607" },
    118	{ }
    119};
    120MODULE_DEVICE_TABLE(of, ms5611_spi_matches);
    121
    122static const struct spi_device_id ms5611_id[] = {
    123	{ "ms5611", MS5611 },
    124	{ "ms5607", MS5607 },
    125	{ }
    126};
    127MODULE_DEVICE_TABLE(spi, ms5611_id);
    128
    129static struct spi_driver ms5611_driver = {
    130	.driver = {
    131		.name = "ms5611",
    132		.of_match_table = ms5611_spi_matches
    133	},
    134	.id_table = ms5611_id,
    135	.probe = ms5611_spi_probe,
    136	.remove = ms5611_spi_remove,
    137};
    138module_spi_driver(ms5611_driver);
    139
    140MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>");
    141MODULE_DESCRIPTION("MS5611 spi driver");
    142MODULE_LICENSE("GPL v2");
    143MODULE_IMPORT_NS(IIO_MS5611);