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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * ADIS16130 Digital Output, High Precision Angular Rate Sensor driver4 *5 * Copyright 2010 Analog Devices Inc.6 */7 8#include <linux/mutex.h>9#include <linux/kernel.h>10#include <linux/spi/spi.h>11#include <linux/module.h>12 13#include <linux/iio/iio.h>14 15#include <linux/unaligned.h>16 17#define ADIS16130_CON         0x018#define ADIS16130_CON_RD      (1 << 6)19#define ADIS16130_IOP         0x120 21/* 1 = data-ready signal low when unread data on all channels; */22#define ADIS16130_IOP_ALL_RDY (1 << 3)23#define ADIS16130_IOP_SYNC    (1 << 0) /* 1 = synchronization enabled */24#define ADIS16130_RATEDATA    0x8 /* Gyroscope output, rate of rotation */25#define ADIS16130_TEMPDATA    0xA /* Temperature output */26#define ADIS16130_RATECS      0x28 /* Gyroscope channel setup */27#define ADIS16130_RATECS_EN   (1 << 3) /* 1 = channel enable; */28#define ADIS16130_TEMPCS      0x2A /* Temperature channel setup */29#define ADIS16130_TEMPCS_EN   (1 << 3)30#define ADIS16130_RATECONV    0x3031#define ADIS16130_TEMPCONV    0x3232#define ADIS16130_MODE        0x3833#define ADIS16130_MODE_24BIT  (1 << 1) /* 1 = 24-bit resolution; */34 35/**36 * struct adis16130_state - device instance specific data37 * @us:			actual spi_device to write data38 * @buf_lock:		mutex to protect tx and rx39 * @buf:		unified tx/rx buffer40 **/41struct adis16130_state {42	struct spi_device		*us;43	struct mutex			buf_lock;44	u8				buf[4] __aligned(IIO_DMA_MINALIGN);45};46 47static int adis16130_spi_read(struct iio_dev *indio_dev, u8 reg_addr, u32 *val)48{49	int ret;50	struct adis16130_state *st = iio_priv(indio_dev);51	struct spi_transfer xfer = {52		.tx_buf = st->buf,53		.rx_buf = st->buf,54		.len = 4,55	};56 57	mutex_lock(&st->buf_lock);58 59	st->buf[0] = ADIS16130_CON_RD | reg_addr;60	st->buf[1] = st->buf[2] = st->buf[3] = 0;61 62	ret = spi_sync_transfer(st->us, &xfer, 1);63	if (ret == 0)64		*val = get_unaligned_be24(&st->buf[1]);65	mutex_unlock(&st->buf_lock);66 67	return ret;68}69 70static int adis16130_read_raw(struct iio_dev *indio_dev,71			      struct iio_chan_spec const *chan,72			      int *val, int *val2,73			      long mask)74{75	int ret;76	u32 temp;77 78	switch (mask) {79	case IIO_CHAN_INFO_RAW:80		/* Take the iio_dev status lock */81		ret = adis16130_spi_read(indio_dev, chan->address, &temp);82		if (ret)83			return ret;84		*val = temp;85		return IIO_VAL_INT;86	case IIO_CHAN_INFO_SCALE:87		switch (chan->type) {88		case IIO_ANGL_VEL:89			/* 0 degree = 838860, 250 degree = 14260608 */90			*val = 250;91			*val2 = 336440817; /* RAD_TO_DEGREE(14260608 - 8388608) */92			return IIO_VAL_FRACTIONAL;93		case IIO_TEMP:94			/* 0C = 8036283, 105C = 9516048 */95			*val = 105000;96			*val2 = 9516048 - 8036283;97			return IIO_VAL_FRACTIONAL;98		default:99			return -EINVAL;100		}101	case IIO_CHAN_INFO_OFFSET:102		switch (chan->type) {103		case IIO_ANGL_VEL:104			*val = -8388608;105			return IIO_VAL_INT;106		case IIO_TEMP:107			*val = -8036283;108			return IIO_VAL_INT;109		default:110			return -EINVAL;111		}112	}113 114	return -EINVAL;115}116 117static const struct iio_chan_spec adis16130_channels[] = {118	{119		.type = IIO_ANGL_VEL,120		.modified = 1,121		.channel2 = IIO_MOD_Z,122		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |123			BIT(IIO_CHAN_INFO_SCALE) |124			BIT(IIO_CHAN_INFO_OFFSET),125		.address = ADIS16130_RATEDATA,126	}, {127		.type = IIO_TEMP,128		.indexed = 1,129		.channel = 0,130		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |131			BIT(IIO_CHAN_INFO_SCALE) |132			BIT(IIO_CHAN_INFO_OFFSET),133		.address = ADIS16130_TEMPDATA,134	}135};136 137static const struct iio_info adis16130_info = {138	.read_raw = &adis16130_read_raw,139};140 141static int adis16130_probe(struct spi_device *spi)142{143	struct adis16130_state *st;144	struct iio_dev *indio_dev;145 146	/* setup the industrialio driver allocated elements */147	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));148	if (!indio_dev)149		return -ENOMEM;150	st = iio_priv(indio_dev);151	/* this is only used for removal purposes */152	spi_set_drvdata(spi, indio_dev);153	st->us = spi;154	mutex_init(&st->buf_lock);155	indio_dev->name = spi->dev.driver->name;156	indio_dev->channels = adis16130_channels;157	indio_dev->num_channels = ARRAY_SIZE(adis16130_channels);158	indio_dev->info = &adis16130_info;159	indio_dev->modes = INDIO_DIRECT_MODE;160 161	return devm_iio_device_register(&spi->dev, indio_dev);162}163 164static struct spi_driver adis16130_driver = {165	.driver = {166		.name = "adis16130",167	},168	.probe = adis16130_probe,169};170module_spi_driver(adis16130_driver);171 172MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");173MODULE_DESCRIPTION("Analog Devices ADIS16130 High Precision Angular Rate");174MODULE_LICENSE("GPL v2");175MODULE_ALIAS("spi:adis16130");176