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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * ADIS16080/100 Yaw Rate Gyroscope with SPI driver4 *5 * Copyright 2010 Analog Devices Inc.6 */7#include <linux/delay.h>8#include <linux/mutex.h>9#include <linux/device.h>10#include <linux/kernel.h>11#include <linux/spi/spi.h>12#include <linux/slab.h>13#include <linux/sysfs.h>14#include <linux/module.h>15 16#include <linux/iio/iio.h>17#include <linux/iio/sysfs.h>18 19#define ADIS16080_DIN_GYRO   (0 << 10) /* Gyroscope output */20#define ADIS16080_DIN_TEMP   (1 << 10) /* Temperature output */21#define ADIS16080_DIN_AIN1   (2 << 10)22#define ADIS16080_DIN_AIN2   (3 << 10)23 24/*25 * 1: Write contents on DIN to control register.26 * 0: No changes to control register.27 */28 29#define ADIS16080_DIN_WRITE  (1 << 15)30 31struct adis16080_chip_info {32	int scale_val;33	int scale_val2;34};35 36/**37 * struct adis16080_state - device instance specific data38 * @us:			actual spi_device to write data39 * @info:		chip specific parameters40 * @buf:		transmit or receive buffer41 * @lock:		lock to protect buffer during reads42 **/43struct adis16080_state {44	struct spi_device		*us;45	const struct adis16080_chip_info *info;46	struct mutex			lock;47 48	__be16 buf __aligned(IIO_DMA_MINALIGN);49};50 51static int adis16080_read_sample(struct iio_dev *indio_dev,52		u16 addr, int *val)53{54	struct adis16080_state *st = iio_priv(indio_dev);55	int ret;56	struct spi_transfer	t[] = {57		{58			.tx_buf		= &st->buf,59			.len		= 2,60			.cs_change	= 1,61		}, {62			.rx_buf		= &st->buf,63			.len		= 2,64		},65	};66 67	st->buf = cpu_to_be16(addr | ADIS16080_DIN_WRITE);68 69	ret = spi_sync_transfer(st->us, t, ARRAY_SIZE(t));70	if (ret == 0)71		*val = sign_extend32(be16_to_cpu(st->buf), 11);72 73	return ret;74}75 76static int adis16080_read_raw(struct iio_dev *indio_dev,77			     struct iio_chan_spec const *chan,78			     int *val,79			     int *val2,80			     long mask)81{82	struct adis16080_state *st = iio_priv(indio_dev);83	int ret;84 85	switch (mask) {86	case IIO_CHAN_INFO_RAW:87		mutex_lock(&st->lock);88		ret = adis16080_read_sample(indio_dev, chan->address, val);89		mutex_unlock(&st->lock);90		return ret ? ret : IIO_VAL_INT;91	case IIO_CHAN_INFO_SCALE:92		switch (chan->type) {93		case IIO_ANGL_VEL:94			*val = st->info->scale_val;95			*val2 = st->info->scale_val2;96			return IIO_VAL_FRACTIONAL;97		case IIO_VOLTAGE:98			/* VREF = 5V, 12 bits */99			*val = 5000;100			*val2 = 12;101			return IIO_VAL_FRACTIONAL_LOG2;102		case IIO_TEMP:103			/* 85 C = 585, 25 C = 0 */104			*val = 85000 - 25000;105			*val2 = 585;106			return IIO_VAL_FRACTIONAL;107		default:108			return -EINVAL;109		}110	case IIO_CHAN_INFO_OFFSET:111		switch (chan->type) {112		case IIO_VOLTAGE:113			/* 2.5 V = 0 */114			*val = 2048;115			return IIO_VAL_INT;116		case IIO_TEMP:117			/* 85 C = 585, 25 C = 0 */118			*val = DIV_ROUND_CLOSEST(25 * 585, 85 - 25);119			return IIO_VAL_INT;120		default:121			return -EINVAL;122		}123	default:124		break;125	}126 127	return -EINVAL;128}129 130static const struct iio_chan_spec adis16080_channels[] = {131	{132		.type = IIO_ANGL_VEL,133		.modified = 1,134		.channel2 = IIO_MOD_Z,135		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |136			BIT(IIO_CHAN_INFO_SCALE),137		.address = ADIS16080_DIN_GYRO,138	}, {139		.type = IIO_VOLTAGE,140		.indexed = 1,141		.channel = 0,142		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |143			BIT(IIO_CHAN_INFO_SCALE) |144			BIT(IIO_CHAN_INFO_OFFSET),145		.address = ADIS16080_DIN_AIN1,146	}, {147		.type = IIO_VOLTAGE,148		.indexed = 1,149		.channel = 1,150		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |151			BIT(IIO_CHAN_INFO_SCALE) |152			BIT(IIO_CHAN_INFO_OFFSET),153		.address = ADIS16080_DIN_AIN2,154	}, {155		.type = IIO_TEMP,156		.indexed = 1,157		.channel = 0,158		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |159			BIT(IIO_CHAN_INFO_SCALE) |160			BIT(IIO_CHAN_INFO_OFFSET),161		.address = ADIS16080_DIN_TEMP,162	}163};164 165static const struct iio_info adis16080_info = {166	.read_raw = &adis16080_read_raw,167};168 169enum {170	ID_ADIS16080,171	ID_ADIS16100,172};173 174static const struct adis16080_chip_info adis16080_chip_info[] = {175	[ID_ADIS16080] = {176		/* 80 degree = 819, 819 rad = 46925 degree */177		.scale_val = 80,178		.scale_val2 = 46925,179	},180	[ID_ADIS16100] = {181		/* 300 degree = 1230, 1230 rad = 70474 degree */182		.scale_val = 300,183		.scale_val2 = 70474,184	},185};186 187static int adis16080_probe(struct spi_device *spi)188{189	const struct spi_device_id *id = spi_get_device_id(spi);190	struct adis16080_state *st;191	struct iio_dev *indio_dev;192 193	/* setup the industrialio driver allocated elements */194	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));195	if (!indio_dev)196		return -ENOMEM;197	st = iio_priv(indio_dev);198 199	mutex_init(&st->lock);200 201	/* Allocate the comms buffers */202	st->us = spi;203	st->info = &adis16080_chip_info[id->driver_data];204 205	indio_dev->name = spi->dev.driver->name;206	indio_dev->channels = adis16080_channels;207	indio_dev->num_channels = ARRAY_SIZE(adis16080_channels);208	indio_dev->info = &adis16080_info;209	indio_dev->modes = INDIO_DIRECT_MODE;210 211	return devm_iio_device_register(&spi->dev, indio_dev);212}213 214static const struct spi_device_id adis16080_ids[] = {215	{ "adis16080", ID_ADIS16080 },216	{ "adis16100", ID_ADIS16100 },217	{},218};219MODULE_DEVICE_TABLE(spi, adis16080_ids);220 221static struct spi_driver adis16080_driver = {222	.driver = {223		.name = "adis16080",224	},225	.probe = adis16080_probe,226	.id_table = adis16080_ids,227};228module_spi_driver(adis16080_driver);229 230MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");231MODULE_DESCRIPTION("Analog Devices ADIS16080/100 Yaw Rate Gyroscope Driver");232MODULE_LICENSE("GPL v2");233