vl53l0x-i2c.c

  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Support for ST VL53L0X FlightSense ToF Ranging Sensor on a i2c bus.
  4 *
  5 * Copyright (C) 2016 STMicroelectronics Imaging Division.
  6 * Copyright (C) 2018 Song Qiang <songqiang1304521@gmail.com>
  7 * Copyright (C) 2020 Ivan Drobyshevskyi <drobyshevskyi@gmail.com>
  8 *
  9 * Datasheet available at
 10 * <https://www.st.com/resource/en/datasheet/vl53l0x.pdf>
 11 *
 12 * Default 7-bit i2c slave address 0x29.
 13 *
 14 * TODO: FIFO buffer, continuous mode, range selection, sensor ID check.
 15 */
 16
 17#include <linux/delay.h>
 18#include <linux/gpio/consumer.h>
 19#include <linux/i2c.h>
 20#include <linux/irq.h>
 21#include <linux/interrupt.h>
 22#include <linux/module.h>
 23#include <linux/unaligned.h>
 24
 25#include <linux/iio/iio.h>
 26#include <linux/iio/buffer.h>
 27#include <linux/iio/trigger.h>
 28#include <linux/iio/trigger_consumer.h>
 29#include <linux/iio/triggered_buffer.h>
 30
 31#define VL_REG_SYSRANGE_START				0x00
 32
 33#define VL_REG_SYSRANGE_MODE_MASK			GENMASK(3, 0)
 34#define VL_REG_SYSRANGE_MODE_SINGLESHOT			0x00
 35#define VL_REG_SYSRANGE_MODE_START_STOP			BIT(0)
 36#define VL_REG_SYSRANGE_MODE_BACKTOBACK			BIT(1)
 37#define VL_REG_SYSRANGE_MODE_TIMED			BIT(2)
 38#define VL_REG_SYSRANGE_MODE_HISTOGRAM			BIT(3)
 39
 40#define VL_REG_SYSTEM_INTERRUPT_CONFIG_GPIO		0x0A
 41#define VL_REG_SYSTEM_INTERRUPT_GPIO_NEW_SAMPLE_READY	BIT(2)
 42
 43#define VL_REG_SYSTEM_INTERRUPT_CLEAR			0x0B
 44
 45#define VL_REG_RESULT_INT_STATUS			0x13
 46#define VL_REG_RESULT_RANGE_STATUS			0x14
 47#define VL_REG_IDENTIFICATION_MODEL_ID			0xC0
 48#define VL_REG_RESULT_RANGE_STATUS_COMPLETE		BIT(0)
 49
 50#define VL53L0X_MODEL_ID_VAL				0xEE
 51#define VL53L0X_CONTINUOUS_MODE				0x02
 52#define VL53L0X_SINGLE_MODE				0x01
 53
 54struct vl53l0x_data {
 55	struct i2c_client *client;
 56	struct completion completion;
 57	struct regulator *vdd_supply;
 58	struct gpio_desc *reset_gpio;
 59	struct iio_trigger *trig;
 60};
 61
 62static int vl53l0x_clear_irq(struct vl53l0x_data *data)
 63{	int ret;
 64
 65	ret = i2c_smbus_write_byte_data(data->client,
 66					VL_REG_SYSTEM_INTERRUPT_CLEAR, 1);
 67	if (ret < 0) {
 68		dev_err(&data->client->dev, "failed to clear irq: %d\n", ret);
 69		return -EINVAL;
 70	}
 71
 72	return 0;
 73}
 74
 75static irqreturn_t vl53l0x_trigger_handler(int irq, void *priv)
 76{
 77	struct iio_poll_func *pf = priv;
 78	struct iio_dev *indio_dev = pf->indio_dev;
 79	struct vl53l0x_data *data = iio_priv(indio_dev);
 80	u8 buffer[12];
 81	int ret;
 82	struct {
 83		u16 chan;
 84		aligned_s64 timestamp;
 85	} scan = { };
 86
 87	ret = i2c_smbus_read_i2c_block_data(data->client,
 88					VL_REG_RESULT_RANGE_STATUS,
 89					sizeof(buffer), buffer);
 90	if (ret < 0)
 91		return ret;
 92	else if (ret != 12)
 93		return -EREMOTEIO;
 94
 95	scan.chan = get_unaligned_be16(&buffer[10]);
 96	iio_push_to_buffers_with_ts(indio_dev, &scan, sizeof(scan),
 97				    iio_get_time_ns(indio_dev));
 98
 99	iio_trigger_notify_done(indio_dev->trig);
100	vl53l0x_clear_irq(data);
101
102	return IRQ_HANDLED;
103}
104
105static irqreturn_t vl53l0x_threaded_irq(int irq, void *priv)
106{
107	struct iio_dev *indio_dev = priv;
108	struct vl53l0x_data *data = iio_priv(indio_dev);
109
110	if (iio_buffer_enabled(indio_dev))
111		iio_trigger_poll_nested(indio_dev->trig);
112	else
113		complete(&data->completion);
114
115	return IRQ_HANDLED;
116}
117
118static int vl53l0x_configure_irq(struct i2c_client *client,
119				 struct iio_dev *indio_dev)
120{
121	int irq_flags = irq_get_trigger_type(client->irq);
122	struct vl53l0x_data *data = iio_priv(indio_dev);
123	int ret;
124
125	if (!irq_flags)
126		irq_flags = IRQF_TRIGGER_FALLING;
127
128	ret = devm_request_threaded_irq(&client->dev, client->irq,
129			NULL, vl53l0x_threaded_irq,
130			irq_flags | IRQF_ONESHOT, indio_dev->name, indio_dev);
131	if (ret) {
132		dev_err(&client->dev, "devm_request_irq error: %d\n", ret);
133		return ret;
134	}
135
136	ret = i2c_smbus_write_byte_data(data->client,
137			VL_REG_SYSTEM_INTERRUPT_CONFIG_GPIO,
138			VL_REG_SYSTEM_INTERRUPT_GPIO_NEW_SAMPLE_READY);
139	if (ret < 0)
140		dev_err(&client->dev, "failed to configure IRQ: %d\n", ret);
141
142	return ret;
143}
144
145static int vl53l0x_read_proximity(struct vl53l0x_data *data,
146				  const struct iio_chan_spec *chan,
147				  int *val)
148{
149	struct i2c_client *client = data->client;
150	u16 tries = 20;
151	u8 buffer[12];
152	int ret;
153	unsigned long time_left;
154
155	ret = i2c_smbus_write_byte_data(client, VL_REG_SYSRANGE_START, 1);
156	if (ret < 0)
157		return ret;
158
159	if (data->client->irq) {
160		reinit_completion(&data->completion);
161
162		time_left = wait_for_completion_timeout(&data->completion, HZ/10);
163		if (time_left == 0)
164			return -ETIMEDOUT;
165
166		ret = vl53l0x_clear_irq(data);
167		if (ret < 0)
168			return ret;
169	} else {
170		do {
171			ret = i2c_smbus_read_byte_data(client,
172					       VL_REG_RESULT_RANGE_STATUS);
173			if (ret < 0)
174				return ret;
175
176			if (ret & VL_REG_RESULT_RANGE_STATUS_COMPLETE)
177				break;
178
179			usleep_range(1000, 5000);
180		} while (--tries);
181		if (!tries)
182			return -ETIMEDOUT;
183	}
184
185	ret = i2c_smbus_read_i2c_block_data(client, VL_REG_RESULT_RANGE_STATUS,
186					    12, buffer);
187	if (ret < 0)
188		return ret;
189	else if (ret != 12)
190		return -EREMOTEIO;
191
192	/* Values should be between 30~1200 in millimeters. */
193	*val = get_unaligned_be16(&buffer[10]);
194
195	return 0;
196}
197
198static const struct iio_chan_spec vl53l0x_channels[] = {
199	{
200		.type = IIO_DISTANCE,
201		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
202				      BIT(IIO_CHAN_INFO_SCALE),
203		.scan_index = 0,
204		.scan_type = {
205			.sign = 'u',
206			.realbits = 12,
207			.storagebits = 16,
208		},
209	},
210	IIO_CHAN_SOFT_TIMESTAMP(1),
211};
212
213static int vl53l0x_read_raw(struct iio_dev *indio_dev,
214			    const struct iio_chan_spec *chan,
215			    int *val, int *val2, long mask)
216{
217	struct vl53l0x_data *data = iio_priv(indio_dev);
218	int ret;
219
220	if (chan->type != IIO_DISTANCE)
221		return -EINVAL;
222
223	switch (mask) {
224	case IIO_CHAN_INFO_RAW:
225		ret = vl53l0x_read_proximity(data, chan, val);
226		if (ret < 0)
227			return ret;
228
229		return IIO_VAL_INT;
230	case IIO_CHAN_INFO_SCALE:
231		*val = 0;
232		*val2 = 1000;
233
234		return IIO_VAL_INT_PLUS_MICRO;
235	default:
236		return -EINVAL;
237	}
238}
239
240static int vl53l0x_validate_trigger(struct iio_dev *indio_dev, struct iio_trigger *trig)
241{
242	struct vl53l0x_data *data = iio_priv(indio_dev);
243
244	return data->trig == trig ? 0 : -EINVAL;
245}
246
247static const struct iio_info vl53l0x_info = {
248	.read_raw = vl53l0x_read_raw,
249	.validate_trigger = vl53l0x_validate_trigger,
250};
251
252static void vl53l0x_power_off(void *_data)
253{
254	struct vl53l0x_data *data = _data;
255
256	gpiod_set_value_cansleep(data->reset_gpio, 1);
257
258	regulator_disable(data->vdd_supply);
259}
260
261static int vl53l0x_power_on(struct vl53l0x_data *data)
262{
263	int ret;
264
265	ret = regulator_enable(data->vdd_supply);
266	if (ret)
267		return ret;
268
269	gpiod_set_value_cansleep(data->reset_gpio, 0);
270
271	usleep_range(3200, 5000);
272
273	return 0;
274}
275
276static int vl53l0x_buffer_postenable(struct iio_dev *indio_dev)
277{
278	struct vl53l0x_data *data = iio_priv(indio_dev);
279
280	return i2c_smbus_write_byte_data(data->client, VL_REG_SYSRANGE_START,
281						VL53L0X_CONTINUOUS_MODE);
282}
283
284static int vl53l0x_buffer_postdisable(struct iio_dev *indio_dev)
285{
286	struct vl53l0x_data *data = iio_priv(indio_dev);
287	int ret;
288
289	ret = i2c_smbus_write_byte_data(data->client, VL_REG_SYSRANGE_START,
290						VL53L0X_SINGLE_MODE);
291	if (ret < 0)
292		return ret;
293
294	/* Let the ongoing reading finish */
295	reinit_completion(&data->completion);
296	wait_for_completion_timeout(&data->completion, HZ / 10);
297
298	return vl53l0x_clear_irq(data);
299}
300
301static const struct iio_buffer_setup_ops iio_triggered_buffer_setup_ops = {
302	.postenable = &vl53l0x_buffer_postenable,
303	.postdisable = &vl53l0x_buffer_postdisable,
304};
305
306static const struct iio_trigger_ops vl53l0x_trigger_ops = {
307	.validate_device = iio_trigger_validate_own_device,
308};
309
310static int vl53l0x_probe(struct i2c_client *client)
311{
312	struct vl53l0x_data *data;
313	struct iio_dev *indio_dev;
314	int ret;
315
316	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
317	if (!indio_dev)
318		return -ENOMEM;
319
320	data = iio_priv(indio_dev);
321	data->client = client;
322	i2c_set_clientdata(client, indio_dev);
323
324	if (!i2c_check_functionality(client->adapter,
325				     I2C_FUNC_SMBUS_READ_I2C_BLOCK |
326				     I2C_FUNC_SMBUS_BYTE_DATA))
327		return -EOPNOTSUPP;
328
329	ret = i2c_smbus_read_byte_data(data->client, VL_REG_IDENTIFICATION_MODEL_ID);
330	if (ret < 0)
331		return -EINVAL;
332
333	if (ret != VL53L0X_MODEL_ID_VAL)
334		dev_info(&client->dev, "Unknown model id: 0x%x", ret);
335
336	data->vdd_supply = devm_regulator_get(&client->dev, "vdd");
337	if (IS_ERR(data->vdd_supply))
338		return dev_err_probe(&client->dev, PTR_ERR(data->vdd_supply),
339				     "Unable to get VDD regulator\n");
340
341	data->reset_gpio = devm_gpiod_get_optional(&client->dev, "reset", GPIOD_OUT_HIGH);
342	if (IS_ERR(data->reset_gpio))
343		return dev_err_probe(&client->dev, PTR_ERR(data->reset_gpio),
344				     "Cannot get reset GPIO\n");
345
346	ret = vl53l0x_power_on(data);
347	if (ret)
348		return dev_err_probe(&client->dev, ret,
349				     "Failed to power on the chip\n");
350
351	ret = devm_add_action_or_reset(&client->dev, vl53l0x_power_off, data);
352	if (ret)
353		return ret;
354
355	indio_dev->name = "vl53l0x";
356	indio_dev->info = &vl53l0x_info;
357	indio_dev->channels = vl53l0x_channels;
358	indio_dev->num_channels = ARRAY_SIZE(vl53l0x_channels);
359	indio_dev->modes = INDIO_DIRECT_MODE;
360
361	/* usage of interrupt is optional */
362	if (client->irq) {
363		init_completion(&data->completion);
364
365		data->trig = devm_iio_trigger_alloc(&client->dev, "%s-dev%d",
366						indio_dev->name,
367						iio_device_id(indio_dev));
368		if (!data->trig)
369			return -ENOMEM;
370
371		data->trig->ops = &vl53l0x_trigger_ops;
372		iio_trigger_set_drvdata(data->trig, indio_dev);
373		ret = devm_iio_trigger_register(&client->dev, data->trig);
374		if (ret)
375			return ret;
376
377		indio_dev->trig = iio_trigger_get(data->trig);
378
379		ret = vl53l0x_configure_irq(client, indio_dev);
380		if (ret)
381			return ret;
382
383		ret = devm_iio_triggered_buffer_setup(&client->dev,
384					indio_dev,
385					NULL,
386					&vl53l0x_trigger_handler,
387					&iio_triggered_buffer_setup_ops);
388		if (ret)
389			return ret;
390	}
391
392	return devm_iio_device_register(&client->dev, indio_dev);
393}
394
395static const struct i2c_device_id vl53l0x_id[] = {
396	{ "vl53l0x" },
397	{ }
398};
399MODULE_DEVICE_TABLE(i2c, vl53l0x_id);
400
401static const struct of_device_id st_vl53l0x_dt_match[] = {
402	{ .compatible = "st,vl53l0x", },
403	{ }
404};
405MODULE_DEVICE_TABLE(of, st_vl53l0x_dt_match);
406
407static struct i2c_driver vl53l0x_driver = {
408	.driver = {
409		.name = "vl53l0x-i2c",
410		.of_match_table = st_vl53l0x_dt_match,
411	},
412	.probe = vl53l0x_probe,
413	.id_table = vl53l0x_id,
414};
415module_i2c_driver(vl53l0x_driver);
416
417MODULE_AUTHOR("Song Qiang <songqiang1304521@gmail.com>");
418MODULE_DESCRIPTION("ST vl53l0x ToF ranging sensor driver");
419MODULE_LICENSE("GPL v2");