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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * itg3200_core.c -- support InvenSense ITG32004 *                   Digital 3-Axis Gyroscope driver5 *6 * Copyright (c) 2011 Christian Strobel <christian.strobel@iis.fraunhofer.de>7 * Copyright (c) 2011 Manuel Stahl <manuel.stahl@iis.fraunhofer.de>8 * Copyright (c) 2012 Thorsten Nowak <thorsten.nowak@iis.fraunhofer.de>9 *10 * TODO:11 * - Support digital low pass filter12 * - Support power management13 */14 15#include <linux/interrupt.h>16#include <linux/irq.h>17#include <linux/i2c.h>18#include <linux/slab.h>19#include <linux/stat.h>20#include <linux/module.h>21#include <linux/mutex.h>22#include <linux/delay.h>23 24#include <linux/iio/iio.h>25#include <linux/iio/sysfs.h>26#include <linux/iio/events.h>27#include <linux/iio/buffer.h>28 29#include <linux/iio/gyro/itg3200.h>30 31 32int itg3200_write_reg_8(struct iio_dev *indio_dev,33		u8 reg_address, u8 val)34{35	struct itg3200 *st = iio_priv(indio_dev);36 37	return i2c_smbus_write_byte_data(st->i2c, 0x80 | reg_address, val);38}39 40int itg3200_read_reg_8(struct iio_dev *indio_dev,41		u8 reg_address, u8 *val)42{43	struct itg3200 *st = iio_priv(indio_dev);44	int ret;45 46	ret = i2c_smbus_read_byte_data(st->i2c, reg_address);47	if (ret < 0)48		return ret;49	*val = ret;50	return 0;51}52 53static int itg3200_read_reg_s16(struct iio_dev *indio_dev, u8 lower_reg_address,54		int *val)55{56	struct itg3200 *st = iio_priv(indio_dev);57	struct i2c_client *client = st->i2c;58	int ret;59	s16 out;60 61	struct i2c_msg msg[2] = {62		{63			.addr = client->addr,64			.flags = client->flags,65			.len = 1,66			.buf = (char *)&lower_reg_address,67		},68		{69			.addr = client->addr,70			.flags = client->flags | I2C_M_RD,71			.len = 2,72			.buf = (char *)&out,73		},74	};75 76	lower_reg_address |= 0x80;77	ret = i2c_transfer(client->adapter, msg, 2);78	be16_to_cpus(&out);79	*val = out;80 81	return (ret == 2) ? 0 : ret;82}83 84static int itg3200_read_raw(struct iio_dev *indio_dev,85		const struct iio_chan_spec *chan,86		int *val, int *val2, long info)87{88	int ret = 0;89	u8 reg;90	u8 regval;91 92	switch (info) {93	case IIO_CHAN_INFO_RAW:94		reg = (u8)chan->address;95		ret = itg3200_read_reg_s16(indio_dev, reg, val);96		return IIO_VAL_INT;97	case IIO_CHAN_INFO_SCALE:98		*val = 0;99		if (chan->type == IIO_TEMP)100			*val2 = 1000000000/280;101		else102			*val2 = 1214142; /* (1 / 14,375) * (PI / 180) */103		return IIO_VAL_INT_PLUS_NANO;104	case IIO_CHAN_INFO_OFFSET:105		/* Only the temperature channel has an offset */106		*val = 23000;107		return IIO_VAL_INT;108	case IIO_CHAN_INFO_SAMP_FREQ:109		ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_DLPF, &regval);110		if (ret)111			return ret;112 113		*val = (regval & ITG3200_DLPF_CFG_MASK) ? 1000 : 8000;114 115		ret = itg3200_read_reg_8(indio_dev,116					 ITG3200_REG_SAMPLE_RATE_DIV,117					 &regval);118		if (ret)119			return ret;120 121		*val /= regval + 1;122		return IIO_VAL_INT;123 124	default:125		return -EINVAL;126	}127}128 129static int itg3200_write_raw(struct iio_dev *indio_dev,130			     struct iio_chan_spec const *chan,131			     int val,132			     int val2,133			     long mask)134{135	struct itg3200 *st = iio_priv(indio_dev);136	int ret;137	u8 t;138 139	switch (mask) {140	case IIO_CHAN_INFO_SAMP_FREQ:141		if (val == 0 || val2 != 0)142			return -EINVAL;143 144		mutex_lock(&st->lock);145 146		ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_DLPF, &t);147		if (ret) {148			mutex_unlock(&st->lock);149			return ret;150		}151		t = ((t & ITG3200_DLPF_CFG_MASK) ? 1000u : 8000u) / val - 1;152 153		ret = itg3200_write_reg_8(indio_dev,154					  ITG3200_REG_SAMPLE_RATE_DIV,155					  t);156 157		mutex_unlock(&st->lock);158		return ret;159 160	default:161		return -EINVAL;162	}163}164 165/*166 * Reset device and internal registers to the power-up-default settings167 * Use the gyro clock as reference, as suggested by the datasheet168 */169static int itg3200_reset(struct iio_dev *indio_dev)170{171	struct itg3200 *st = iio_priv(indio_dev);172	int ret;173 174	dev_dbg(&st->i2c->dev, "reset device");175 176	ret = itg3200_write_reg_8(indio_dev,177			ITG3200_REG_POWER_MANAGEMENT,178			ITG3200_RESET);179	if (ret) {180		dev_err(&st->i2c->dev, "error resetting device");181		goto error_ret;182	}183 184	/* Wait for PLL (1ms according to datasheet) */185	udelay(1500);186 187	ret = itg3200_write_reg_8(indio_dev,188			ITG3200_REG_IRQ_CONFIG,189			ITG3200_IRQ_ACTIVE_HIGH |190			ITG3200_IRQ_PUSH_PULL |191			ITG3200_IRQ_LATCH_50US_PULSE |192			ITG3200_IRQ_LATCH_CLEAR_ANY);193 194	if (ret)195		dev_err(&st->i2c->dev, "error init device");196 197error_ret:198	return ret;199}200 201/* itg3200_enable_full_scale() - Disables the digital low pass filter */202static int itg3200_enable_full_scale(struct iio_dev *indio_dev)203{204	u8 val;205	int ret;206 207	ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_DLPF, &val);208	if (ret)209		goto err_ret;210 211	val |= ITG3200_DLPF_FS_SEL_2000;212	return itg3200_write_reg_8(indio_dev, ITG3200_REG_DLPF, val);213 214err_ret:215	return ret;216}217 218static int itg3200_initial_setup(struct iio_dev *indio_dev)219{220	struct itg3200 *st = iio_priv(indio_dev);221	int ret;222	u8 val;223 224	ret = itg3200_reset(indio_dev);225	if (ret)226		goto err_ret;227 228	ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_ADDRESS, &val);229	if (ret)230		goto err_ret;231 232	if (((val >> 1) & 0x3f) != 0x34) {233		dev_err(&st->i2c->dev, "invalid reg value 0x%02x", val);234		ret = -ENXIO;235		goto err_ret;236	}237 238	ret = itg3200_enable_full_scale(indio_dev);239err_ret:240	return ret;241}242 243static const struct iio_mount_matrix *244itg3200_get_mount_matrix(const struct iio_dev *indio_dev,245			  const struct iio_chan_spec *chan)246{247	struct itg3200 *data = iio_priv(indio_dev);248 249	return &data->orientation;250}251 252static const struct iio_chan_spec_ext_info itg3200_ext_info[] = {253	IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, itg3200_get_mount_matrix),254	{ }255};256 257#define ITG3200_ST						\258	{ .sign = 's', .realbits = 16, .storagebits = 16, .endianness = IIO_BE }259 260#define ITG3200_GYRO_CHAN(_mod) { \261	.type = IIO_ANGL_VEL, \262	.modified = 1, \263	.channel2 = IIO_MOD_ ## _mod, \264	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \265	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \266	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \267	.address = ITG3200_REG_GYRO_ ## _mod ## OUT_H, \268	.scan_index = ITG3200_SCAN_GYRO_ ## _mod, \269	.scan_type = ITG3200_ST, \270	.ext_info = itg3200_ext_info, \271}272 273static const struct iio_chan_spec itg3200_channels[] = {274	{275		.type = IIO_TEMP,276		.channel2 = IIO_NO_MOD,277		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),278		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |279		BIT(IIO_CHAN_INFO_SCALE),280		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),281		.address = ITG3200_REG_TEMP_OUT_H,282		.scan_index = ITG3200_SCAN_TEMP,283		.scan_type = ITG3200_ST,284	},285	ITG3200_GYRO_CHAN(X),286	ITG3200_GYRO_CHAN(Y),287	ITG3200_GYRO_CHAN(Z),288	IIO_CHAN_SOFT_TIMESTAMP(ITG3200_SCAN_ELEMENTS),289};290 291static const struct iio_info itg3200_info = {292	.read_raw = &itg3200_read_raw,293	.write_raw = &itg3200_write_raw,294};295 296static const unsigned long itg3200_available_scan_masks[] = { 0xffffffff, 0x0 };297 298static int itg3200_probe(struct i2c_client *client)299{300	int ret;301	struct itg3200 *st;302	struct iio_dev *indio_dev;303 304	dev_dbg(&client->dev, "probe I2C dev with IRQ %i", client->irq);305 306	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));307	if (!indio_dev)308		return -ENOMEM;309 310	st = iio_priv(indio_dev);311 312	ret = iio_read_mount_matrix(&client->dev, &st->orientation);313	if (ret)314		return ret;315 316	i2c_set_clientdata(client, indio_dev);317	st->i2c = client;318 319	indio_dev->name = client->dev.driver->name;320	indio_dev->channels = itg3200_channels;321	indio_dev->num_channels = ARRAY_SIZE(itg3200_channels);322	indio_dev->available_scan_masks = itg3200_available_scan_masks;323	indio_dev->info = &itg3200_info;324	indio_dev->modes = INDIO_DIRECT_MODE;325 326	ret = itg3200_buffer_configure(indio_dev);327	if (ret)328		return ret;329 330	if (client->irq) {331		ret = itg3200_probe_trigger(indio_dev);332		if (ret)333			goto error_unconfigure_buffer;334	}335 336	ret = itg3200_initial_setup(indio_dev);337	if (ret)338		goto error_remove_trigger;339 340	mutex_init(&st->lock);341 342	ret = iio_device_register(indio_dev);343	if (ret)344		goto error_remove_trigger;345 346	return 0;347 348error_remove_trigger:349	if (client->irq)350		itg3200_remove_trigger(indio_dev);351error_unconfigure_buffer:352	itg3200_buffer_unconfigure(indio_dev);353	return ret;354}355 356static void itg3200_remove(struct i2c_client *client)357{358	struct iio_dev *indio_dev = i2c_get_clientdata(client);359 360	iio_device_unregister(indio_dev);361 362	if (client->irq)363		itg3200_remove_trigger(indio_dev);364 365	itg3200_buffer_unconfigure(indio_dev);366}367 368static int itg3200_suspend(struct device *dev)369{370	struct iio_dev *indio_dev = dev_get_drvdata(dev);371	struct itg3200 *st = iio_priv(indio_dev);372 373	dev_dbg(&st->i2c->dev, "suspend device");374 375	return itg3200_write_reg_8(indio_dev, ITG3200_REG_POWER_MANAGEMENT,376				   ITG3200_SLEEP);377}378 379static int itg3200_resume(struct device *dev)380{381	struct iio_dev *indio_dev = dev_get_drvdata(dev);382 383	return itg3200_initial_setup(indio_dev);384}385 386static DEFINE_SIMPLE_DEV_PM_OPS(itg3200_pm_ops, itg3200_suspend,387				itg3200_resume);388 389static const struct i2c_device_id itg3200_id[] = {390	{ "itg3200" },391	{ }392};393MODULE_DEVICE_TABLE(i2c, itg3200_id);394 395static const struct of_device_id itg3200_of_match[] = {396	{ .compatible = "invensense,itg3200" },397	{ }398};399MODULE_DEVICE_TABLE(of, itg3200_of_match);400 401static struct i2c_driver itg3200_driver = {402	.driver = {403		.name	= "itg3200",404		.of_match_table = itg3200_of_match,405		.pm	= pm_sleep_ptr(&itg3200_pm_ops),406	},407	.id_table	= itg3200_id,408	.probe		= itg3200_probe,409	.remove		= itg3200_remove,410};411 412module_i2c_driver(itg3200_driver);413 414MODULE_AUTHOR("Christian Strobel <christian.strobel@iis.fraunhofer.de>");415MODULE_DESCRIPTION("ITG3200 Gyroscope I2C driver");416MODULE_LICENSE("GPL v2");417