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
24#include <linux/iio/iio.h>
25
26#define VL_REG_SYSRANGE_START				0x00
27
28#define VL_REG_SYSRANGE_MODE_MASK			GENMASK(3, 0)
29#define VL_REG_SYSRANGE_MODE_SINGLESHOT			0x00
30#define VL_REG_SYSRANGE_MODE_START_STOP			BIT(0)
31#define VL_REG_SYSRANGE_MODE_BACKTOBACK			BIT(1)
32#define VL_REG_SYSRANGE_MODE_TIMED			BIT(2)
33#define VL_REG_SYSRANGE_MODE_HISTOGRAM			BIT(3)
34
35#define VL_REG_SYSTEM_INTERRUPT_CONFIG_GPIO		0x0A
36#define VL_REG_SYSTEM_INTERRUPT_GPIO_NEW_SAMPLE_READY	BIT(2)
37
38#define VL_REG_SYSTEM_INTERRUPT_CLEAR			0x0B
39
40#define VL_REG_RESULT_INT_STATUS			0x13
41#define VL_REG_RESULT_RANGE_STATUS			0x14
42#define VL_REG_RESULT_RANGE_STATUS_COMPLETE		BIT(0)
43
44struct vl53l0x_data {
45	struct i2c_client *client;
46	struct completion completion;
47	struct regulator *vdd_supply;
48	struct gpio_desc *reset_gpio;
49};
50
51static irqreturn_t vl53l0x_handle_irq(int irq, void *priv)
52{
53	struct iio_dev *indio_dev = priv;
54	struct vl53l0x_data *data = iio_priv(indio_dev);
55
56	complete(&data->completion);
57
58	return IRQ_HANDLED;
59}
60
61static int vl53l0x_configure_irq(struct i2c_client *client,
62				 struct iio_dev *indio_dev)
63{
64	int irq_flags = irq_get_trigger_type(client->irq);
65	struct vl53l0x_data *data = iio_priv(indio_dev);
66	int ret;
67
68	if (!irq_flags)
69		irq_flags = IRQF_TRIGGER_FALLING;
70
71	ret = devm_request_irq(&client->dev, client->irq, vl53l0x_handle_irq,
72			irq_flags, indio_dev->name, indio_dev);
73	if (ret) {
74		dev_err(&client->dev, "devm_request_irq error: %d\n", ret);
75		return ret;
76	}
77
78	ret = i2c_smbus_write_byte_data(data->client,
79			VL_REG_SYSTEM_INTERRUPT_CONFIG_GPIO,
80			VL_REG_SYSTEM_INTERRUPT_GPIO_NEW_SAMPLE_READY);
81	if (ret < 0)
82		dev_err(&client->dev, "failed to configure IRQ: %d\n", ret);
83
84	return ret;
85}
86
87static void vl53l0x_clear_irq(struct vl53l0x_data *data)
88{
89	struct device *dev = &data->client->dev;
90	int ret;
91
92	ret = i2c_smbus_write_byte_data(data->client,
93					VL_REG_SYSTEM_INTERRUPT_CLEAR, 1);
94	if (ret < 0)
95		dev_err(dev, "failed to clear error irq: %d\n", ret);
96
97	ret = i2c_smbus_write_byte_data(data->client,
98					VL_REG_SYSTEM_INTERRUPT_CLEAR, 0);
99	if (ret < 0)
100		dev_err(dev, "failed to clear range irq: %d\n", ret);
101
102	ret = i2c_smbus_read_byte_data(data->client, VL_REG_RESULT_INT_STATUS);
103	if (ret < 0 || ret & 0x07)
104		dev_err(dev, "failed to clear irq: %d\n", ret);
105}
106
107static int vl53l0x_read_proximity(struct vl53l0x_data *data,
108				  const struct iio_chan_spec *chan,
109				  int *val)
110{
111	struct i2c_client *client = data->client;
112	u16 tries = 20;
113	u8 buffer[12];
114	int ret;
115	unsigned long time_left;
116
117	ret = i2c_smbus_write_byte_data(client, VL_REG_SYSRANGE_START, 1);
118	if (ret < 0)
119		return ret;
120
121	if (data->client->irq) {
122		reinit_completion(&data->completion);
123
124		time_left = wait_for_completion_timeout(&data->completion, HZ/10);
125		if (time_left == 0)
126			return -ETIMEDOUT;
127
128		vl53l0x_clear_irq(data);
129	} else {
130		do {
131			ret = i2c_smbus_read_byte_data(client,
132					       VL_REG_RESULT_RANGE_STATUS);
133			if (ret < 0)
134				return ret;
135
136			if (ret & VL_REG_RESULT_RANGE_STATUS_COMPLETE)
137				break;
138
139			usleep_range(1000, 5000);
140		} while (--tries);
141		if (!tries)
142			return -ETIMEDOUT;
143	}
144
145	ret = i2c_smbus_read_i2c_block_data(client, VL_REG_RESULT_RANGE_STATUS,
146					    12, buffer);
147	if (ret < 0)
148		return ret;
149	else if (ret != 12)
150		return -EREMOTEIO;
151
152	/* Values should be between 30~1200 in millimeters. */
153	*val = (buffer[10] << 8) + buffer[11];
154
155	return 0;
156}
157
158static const struct iio_chan_spec vl53l0x_channels[] = {
159	{
160		.type = IIO_DISTANCE,
161		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
162				      BIT(IIO_CHAN_INFO_SCALE),
163	},
164};
165
166static int vl53l0x_read_raw(struct iio_dev *indio_dev,
167			    const struct iio_chan_spec *chan,
168			    int *val, int *val2, long mask)
169{
170	struct vl53l0x_data *data = iio_priv(indio_dev);
171	int ret;
172
173	if (chan->type != IIO_DISTANCE)
174		return -EINVAL;
175
176	switch (mask) {
177	case IIO_CHAN_INFO_RAW:
178		ret = vl53l0x_read_proximity(data, chan, val);
179		if (ret < 0)
180			return ret;
181
182		return IIO_VAL_INT;
183	case IIO_CHAN_INFO_SCALE:
184		*val = 0;
185		*val2 = 1000;
186
187		return IIO_VAL_INT_PLUS_MICRO;
188	default:
189		return -EINVAL;
190	}
191}
192
193static const struct iio_info vl53l0x_info = {
194	.read_raw = vl53l0x_read_raw,
195};
196
197static void vl53l0x_power_off(void *_data)
198{
199	struct vl53l0x_data *data = _data;
200
201	gpiod_set_value_cansleep(data->reset_gpio, 1);
202
203	regulator_disable(data->vdd_supply);
204}
205
206static int vl53l0x_power_on(struct vl53l0x_data *data)
207{
208	int ret;
209
210	ret = regulator_enable(data->vdd_supply);
211	if (ret)
212		return ret;
213
214	gpiod_set_value_cansleep(data->reset_gpio, 0);
215
216	usleep_range(3200, 5000);
217
218	return 0;
219}
220
221static int vl53l0x_probe(struct i2c_client *client)
222{
223	struct vl53l0x_data *data;
224	struct iio_dev *indio_dev;
225	int error;
226
227	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
228	if (!indio_dev)
229		return -ENOMEM;
230
231	data = iio_priv(indio_dev);
232	data->client = client;
233	i2c_set_clientdata(client, indio_dev);
234
235	if (!i2c_check_functionality(client->adapter,
236				     I2C_FUNC_SMBUS_READ_I2C_BLOCK |
237				     I2C_FUNC_SMBUS_BYTE_DATA))
238		return -EOPNOTSUPP;
239
240	data->vdd_supply = devm_regulator_get(&client->dev, "vdd");
241	if (IS_ERR(data->vdd_supply))
242		return dev_err_probe(&client->dev, PTR_ERR(data->vdd_supply),
243				     "Unable to get VDD regulator\n");
244
245	data->reset_gpio = devm_gpiod_get_optional(&client->dev, "reset", GPIOD_OUT_HIGH);
246	if (IS_ERR(data->reset_gpio))
247		return dev_err_probe(&client->dev, PTR_ERR(data->reset_gpio),
248				     "Cannot get reset GPIO\n");
249
250	error = vl53l0x_power_on(data);
251	if (error)
252		return dev_err_probe(&client->dev, error,
253				     "Failed to power on the chip\n");
254
255	error = devm_add_action_or_reset(&client->dev, vl53l0x_power_off, data);
256	if (error)
257		return dev_err_probe(&client->dev, error,
258				     "Failed to install poweroff action\n");
259
260	indio_dev->name = "vl53l0x";
261	indio_dev->info = &vl53l0x_info;
262	indio_dev->channels = vl53l0x_channels;
263	indio_dev->num_channels = ARRAY_SIZE(vl53l0x_channels);
264	indio_dev->modes = INDIO_DIRECT_MODE;
265
266	/* usage of interrupt is optional */
267	if (client->irq) {
268		int ret;
269
270		init_completion(&data->completion);
271
272		ret = vl53l0x_configure_irq(client, indio_dev);
273		if (ret)
274			return ret;
275	}
276
277	return devm_iio_device_register(&client->dev, indio_dev);
278}
279
280static const struct i2c_device_id vl53l0x_id[] = {
281	{ "vl53l0x", 0 },
282	{ }
283};
284MODULE_DEVICE_TABLE(i2c, vl53l0x_id);
285
286static const struct of_device_id st_vl53l0x_dt_match[] = {
287	{ .compatible = "st,vl53l0x", },
288	{ }
289};
290MODULE_DEVICE_TABLE(of, st_vl53l0x_dt_match);
291
292static struct i2c_driver vl53l0x_driver = {
293	.driver = {
294		.name = "vl53l0x-i2c",
295		.of_match_table = st_vl53l0x_dt_match,
296	},
297	.probe = vl53l0x_probe,
298	.id_table = vl53l0x_id,
299};
300module_i2c_driver(vl53l0x_driver);
301
302MODULE_AUTHOR("Song Qiang <songqiang1304521@gmail.com>");
303MODULE_DESCRIPTION("ST vl53l0x ToF ranging sensor driver");
304MODULE_LICENSE("GPL v2");
305