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author | Gregor Boirie <gregor.boirie@parrot.com> | 2016-09-13 14:23:14 +0200 |
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committer | Jonathan Cameron <jic23@kernel.org> | 2016-09-18 19:42:21 +0100 |
commit | 03b262f2bbf43b82eaef82ffb3bc671d5b5c8da1 (patch) | |
tree | aba7517ff0dfaa1fbf5367985736826cf40974d3 /drivers/iio/pressure/zpa2326_spi.c | |
parent | 063e3303a93fcd64554730145361f102236724cb (diff) | |
download | linux-stable-03b262f2bbf43b82eaef82ffb3bc671d5b5c8da1.tar.gz linux-stable-03b262f2bbf43b82eaef82ffb3bc671d5b5c8da1.tar.bz2 linux-stable-03b262f2bbf43b82eaef82ffb3bc671d5b5c8da1.zip |
iio:pressure: initial zpa2326 barometer support
Introduce driver for Murata ZPA2326 pressure and temperature sensor:
http://www.murata.com/en-us/products/productdetail?partno=ZPA2326-0311A-R
Signed-off-by: Gregor Boirie <gregor.boirie@parrot.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Diffstat (limited to 'drivers/iio/pressure/zpa2326_spi.c')
-rw-r--r-- | drivers/iio/pressure/zpa2326_spi.c | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/drivers/iio/pressure/zpa2326_spi.c b/drivers/iio/pressure/zpa2326_spi.c new file mode 100644 index 000000000000..bd2c1c319fca --- /dev/null +++ b/drivers/iio/pressure/zpa2326_spi.c @@ -0,0 +1,103 @@ +/* + * Murata ZPA2326 SPI pressure and temperature sensor driver + * + * Copyright (c) 2016 Parrot S.A. + * + * Author: Gregor Boirie <gregor.boirie@parrot.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. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + */ + +#include <linux/module.h> +#include <linux/regmap.h> +#include <linux/spi/spi.h> +#include <linux/of_device.h> +#include "zpa2326.h" + +/* + * read_flag_mask: + * - address bit 7 must be set to request a register read operation + * - address bit 6 must be set to request register address auto increment + */ +static const struct regmap_config zpa2326_regmap_spi_config = { + .reg_bits = 8, + .val_bits = 8, + .writeable_reg = zpa2326_isreg_writeable, + .readable_reg = zpa2326_isreg_readable, + .precious_reg = zpa2326_isreg_precious, + .max_register = ZPA2326_TEMP_OUT_H_REG, + .read_flag_mask = BIT(7) | BIT(6), + .cache_type = REGCACHE_NONE, +}; + +static int zpa2326_probe_spi(struct spi_device *spi) +{ + struct regmap *regmap; + int err; + + regmap = devm_regmap_init_spi(spi, &zpa2326_regmap_spi_config); + if (IS_ERR(regmap)) { + dev_err(&spi->dev, "failed to init registers map"); + return PTR_ERR(regmap); + } + + /* + * Enforce SPI slave settings to prevent from DT misconfiguration. + * + * Clock is idle high. Sampling happens on trailing edge, i.e., rising + * edge. Maximum bus frequency is 1 MHz. Registers are 8 bits wide. + */ + spi->mode = SPI_MODE_3; + spi->max_speed_hz = min(spi->max_speed_hz, 1000000U); + spi->bits_per_word = 8; + err = spi_setup(spi); + if (err < 0) + return err; + + return zpa2326_probe(&spi->dev, spi_get_device_id(spi)->name, + spi->irq, ZPA2326_DEVICE_ID, regmap); +} + +static int zpa2326_remove_spi(struct spi_device *spi) +{ + zpa2326_remove(&spi->dev); + + return 0; +} + +static const struct spi_device_id zpa2326_spi_ids[] = { + { "zpa2326", 0 }, + { }, +}; +MODULE_DEVICE_TABLE(spi, zpa2326_spi_ids); + +#if defined(CONFIG_OF) +static const struct of_device_id zpa2326_spi_matches[] = { + { .compatible = "murata,zpa2326" }, + { } +}; +MODULE_DEVICE_TABLE(of, zpa2326_spi_matches); +#endif + +static struct spi_driver zpa2326_spi_driver = { + .driver = { + .name = "zpa2326-spi", + .of_match_table = of_match_ptr(zpa2326_spi_matches), + .pm = ZPA2326_PM_OPS, + }, + .probe = zpa2326_probe_spi, + .remove = zpa2326_remove_spi, + .id_table = zpa2326_spi_ids, +}; +module_spi_driver(zpa2326_spi_driver); + +MODULE_AUTHOR("Gregor Boirie <gregor.boirie@parrot.com>"); +MODULE_DESCRIPTION("SPI driver for Murata ZPA2326 pressure sensor"); +MODULE_LICENSE("GPL v2"); |