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/i2c.h>
19 #include <linux/interrupt.h>
20 #include <linux/module.h>
21
22 #include <linux/iio/iio.h>
23
24 #define VL_REG_SYSRANGE_START 0x00
25
26 #define VL_REG_SYSRANGE_MODE_MASK GENMASK(3, 0)
27 #define VL_REG_SYSRANGE_MODE_SINGLESHOT 0x00
28 #define VL_REG_SYSRANGE_MODE_START_STOP BIT(0)
29 #define VL_REG_SYSRANGE_MODE_BACKTOBACK BIT(1)
30 #define VL_REG_SYSRANGE_MODE_TIMED BIT(2)
31 #define VL_REG_SYSRANGE_MODE_HISTOGRAM BIT(3)
32
33 #define VL_REG_SYSTEM_INTERRUPT_CONFIG_GPIO 0x0A
34 #define VL_REG_SYSTEM_INTERRUPT_GPIO_NEW_SAMPLE_READY BIT(2)
35
36 #define VL_REG_SYSTEM_INTERRUPT_CLEAR 0x0B
37
38 #define VL_REG_RESULT_INT_STATUS 0x13
39 #define VL_REG_RESULT_RANGE_STATUS 0x14
40 #define VL_REG_RESULT_RANGE_STATUS_COMPLETE BIT(0)
41
42 struct vl53l0x_data {
43 struct i2c_client *client;
44 struct completion completion;
45 };
46
vl53l0x_handle_irq(int irq, void *priv)47 static irqreturn_t vl53l0x_handle_irq(int irq, void *priv)
48 {
49 struct iio_dev *indio_dev = priv;
50 struct vl53l0x_data *data = iio_priv(indio_dev);
51
52 complete(&data->completion);
53
54 return IRQ_HANDLED;
55 }
56
vl53l0x_configure_irq(struct i2c_client *client, struct iio_dev *indio_dev)57 static int vl53l0x_configure_irq(struct i2c_client *client,
58 struct iio_dev *indio_dev)
59 {
60 struct vl53l0x_data *data = iio_priv(indio_dev);
61 int ret;
62
63 ret = devm_request_irq(&client->dev, client->irq, vl53l0x_handle_irq,
64 IRQF_TRIGGER_FALLING, indio_dev->name, indio_dev);
65 if (ret) {
66 dev_err(&client->dev, "devm_request_irq error: %d\n", ret);
67 return ret;
68 }
69
70 ret = i2c_smbus_write_byte_data(data->client,
71 VL_REG_SYSTEM_INTERRUPT_CONFIG_GPIO,
72 VL_REG_SYSTEM_INTERRUPT_GPIO_NEW_SAMPLE_READY);
73 if (ret < 0)
74 dev_err(&client->dev, "failed to configure IRQ: %d\n", ret);
75
76 return ret;
77 }
78
vl53l0x_clear_irq(struct vl53l0x_data *data)79 static void vl53l0x_clear_irq(struct vl53l0x_data *data)
80 {
81 struct device *dev = &data->client->dev;
82 int ret;
83
84 ret = i2c_smbus_write_byte_data(data->client,
85 VL_REG_SYSTEM_INTERRUPT_CLEAR, 1);
86 if (ret < 0)
87 dev_err(dev, "failed to clear error irq: %d\n", ret);
88
89 ret = i2c_smbus_write_byte_data(data->client,
90 VL_REG_SYSTEM_INTERRUPT_CLEAR, 0);
91 if (ret < 0)
92 dev_err(dev, "failed to clear range irq: %d\n", ret);
93
94 ret = i2c_smbus_read_byte_data(data->client, VL_REG_RESULT_INT_STATUS);
95 if (ret < 0 || ret & 0x07)
96 dev_err(dev, "failed to clear irq: %d\n", ret);
97 }
98
vl53l0x_read_proximity(struct vl53l0x_data *data, const struct iio_chan_spec *chan, int *val)99 static int vl53l0x_read_proximity(struct vl53l0x_data *data,
100 const struct iio_chan_spec *chan,
101 int *val)
102 {
103 struct i2c_client *client = data->client;
104 u16 tries = 20;
105 u8 buffer[12];
106 int ret;
107 unsigned long time_left;
108
109 ret = i2c_smbus_write_byte_data(client, VL_REG_SYSRANGE_START, 1);
110 if (ret < 0)
111 return ret;
112
113 if (data->client->irq) {
114 reinit_completion(&data->completion);
115
116 time_left = wait_for_completion_timeout(&data->completion, HZ/10);
117 if (time_left == 0)
118 return -ETIMEDOUT;
119
120 vl53l0x_clear_irq(data);
121 } else {
122 do {
123 ret = i2c_smbus_read_byte_data(client,
124 VL_REG_RESULT_RANGE_STATUS);
125 if (ret < 0)
126 return ret;
127
128 if (ret & VL_REG_RESULT_RANGE_STATUS_COMPLETE)
129 break;
130
131 usleep_range(1000, 5000);
132 } while (--tries);
133 if (!tries)
134 return -ETIMEDOUT;
135 }
136
137 ret = i2c_smbus_read_i2c_block_data(client, VL_REG_RESULT_RANGE_STATUS,
138 12, buffer);
139 if (ret < 0)
140 return ret;
141 else if (ret != 12)
142 return -EREMOTEIO;
143
144 /* Values should be between 30~1200 in millimeters. */
145 *val = (buffer[10] << 8) + buffer[11];
146
147 return 0;
148 }
149
150 static const struct iio_chan_spec vl53l0x_channels[] = {
151 {
152 .type = IIO_DISTANCE,
153 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
154 BIT(IIO_CHAN_INFO_SCALE),
155 },
156 };
157
vl53l0x_read_raw(struct iio_dev *indio_dev, const struct iio_chan_spec *chan, int *val, int *val2, long mask)158 static int vl53l0x_read_raw(struct iio_dev *indio_dev,
159 const struct iio_chan_spec *chan,
160 int *val, int *val2, long mask)
161 {
162 struct vl53l0x_data *data = iio_priv(indio_dev);
163 int ret;
164
165 if (chan->type != IIO_DISTANCE)
166 return -EINVAL;
167
168 switch (mask) {
169 case IIO_CHAN_INFO_RAW:
170 ret = vl53l0x_read_proximity(data, chan, val);
171 if (ret < 0)
172 return ret;
173
174 return IIO_VAL_INT;
175 case IIO_CHAN_INFO_SCALE:
176 *val = 0;
177 *val2 = 1000;
178
179 return IIO_VAL_INT_PLUS_MICRO;
180 default:
181 return -EINVAL;
182 }
183 }
184
185 static const struct iio_info vl53l0x_info = {
186 .read_raw = vl53l0x_read_raw,
187 };
188
vl53l0x_probe(struct i2c_client *client)189 static int vl53l0x_probe(struct i2c_client *client)
190 {
191 struct vl53l0x_data *data;
192 struct iio_dev *indio_dev;
193
194 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
195 if (!indio_dev)
196 return -ENOMEM;
197
198 data = iio_priv(indio_dev);
199 data->client = client;
200 i2c_set_clientdata(client, indio_dev);
201
202 if (!i2c_check_functionality(client->adapter,
203 I2C_FUNC_SMBUS_READ_I2C_BLOCK |
204 I2C_FUNC_SMBUS_BYTE_DATA))
205 return -EOPNOTSUPP;
206
207 indio_dev->name = "vl53l0x";
208 indio_dev->info = &vl53l0x_info;
209 indio_dev->channels = vl53l0x_channels;
210 indio_dev->num_channels = ARRAY_SIZE(vl53l0x_channels);
211 indio_dev->modes = INDIO_DIRECT_MODE;
212
213 /* usage of interrupt is optional */
214 if (client->irq) {
215 int ret;
216
217 init_completion(&data->completion);
218
219 ret = vl53l0x_configure_irq(client, indio_dev);
220 if (ret)
221 return ret;
222 }
223
224 return devm_iio_device_register(&client->dev, indio_dev);
225 }
226
227 static const struct of_device_id st_vl53l0x_dt_match[] = {
228 { .compatible = "st,vl53l0x", },
229 { }
230 };
231 MODULE_DEVICE_TABLE(of, st_vl53l0x_dt_match);
232
233 static struct i2c_driver vl53l0x_driver = {
234 .driver = {
235 .name = "vl53l0x-i2c",
236 .of_match_table = st_vl53l0x_dt_match,
237 },
238 .probe_new = vl53l0x_probe,
239 };
240 module_i2c_driver(vl53l0x_driver);
241
242 MODULE_AUTHOR("Song Qiang <songqiang1304521@gmail.com>");
243 MODULE_DESCRIPTION("ST vl53l0x ToF ranging sensor driver");
244 MODULE_LICENSE("GPL v2");
245