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11#include <linux/err.h>
12#include <linux/init.h>
13#include <linux/i2c.h>
14#include <linux/delay.h>
15#include <linux/module.h>
16#include <linux/mod_devicetable.h>
17#include <linux/pm_runtime.h>
18#include <linux/iio/iio.h>
19#include <linux/iio/sysfs.h>
20#include <linux/iio/buffer.h>
21#include <linux/iio/trigger.h>
22#include <linux/iio/triggered_buffer.h>
23#include <linux/iio/trigger_consumer.h>
24
25#define LIDAR_REG_CONTROL 0x00
26#define LIDAR_REG_CONTROL_ACQUIRE BIT(2)
27
28#define LIDAR_REG_STATUS 0x01
29#define LIDAR_REG_STATUS_INVALID BIT(3)
30#define LIDAR_REG_STATUS_READY BIT(0)
31
32#define LIDAR_REG_DATA_HBYTE 0x0f
33#define LIDAR_REG_DATA_LBYTE 0x10
34#define LIDAR_REG_DATA_WORD_READ BIT(7)
35
36#define LIDAR_REG_PWR_CONTROL 0x65
37
38#define LIDAR_DRV_NAME "lidar"
39
40struct lidar_data {
41 struct iio_dev *indio_dev;
42 struct i2c_client *client;
43
44 int (*xfer)(struct lidar_data *data, u8 reg, u8 *val, int len);
45 int i2c_enabled;
46
47
48 struct {
49 u16 chan;
50 s64 timestamp __aligned(8);
51 } scan;
52};
53
54static const struct iio_chan_spec lidar_channels[] = {
55 {
56 .type = IIO_DISTANCE,
57 .info_mask_separate =
58 BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
59 .scan_index = 0,
60 .scan_type = {
61 .sign = 'u',
62 .realbits = 16,
63 .storagebits = 16,
64 },
65 },
66 IIO_CHAN_SOFT_TIMESTAMP(1),
67};
68
69static int lidar_i2c_xfer(struct lidar_data *data, u8 reg, u8 *val, int len)
70{
71 struct i2c_client *client = data->client;
72 struct i2c_msg msg[2];
73 int ret;
74
75 msg[0].addr = client->addr;
76 msg[0].flags = client->flags | I2C_M_STOP;
77 msg[0].len = 1;
78 msg[0].buf = (char *) ®
79
80 msg[1].addr = client->addr;
81 msg[1].flags = client->flags | I2C_M_RD;
82 msg[1].len = len;
83 msg[1].buf = (char *) val;
84
85 ret = i2c_transfer(client->adapter, msg, 2);
86
87 return (ret == 2) ? 0 : -EIO;
88}
89
90static int lidar_smbus_xfer(struct lidar_data *data, u8 reg, u8 *val, int len)
91{
92 struct i2c_client *client = data->client;
93 int ret;
94
95
96
97
98
99
100 while (len--) {
101 ret = i2c_smbus_write_byte(client, reg++);
102 if (ret < 0) {
103 dev_err(&client->dev, "cannot write addr value");
104 return ret;
105 }
106
107 ret = i2c_smbus_read_byte(client);
108 if (ret < 0) {
109 dev_err(&client->dev, "cannot read data value");
110 return ret;
111 }
112
113 *(val++) = ret;
114 }
115
116 return 0;
117}
118
119static int lidar_read_byte(struct lidar_data *data, u8 reg)
120{
121 int ret;
122 u8 val;
123
124 ret = data->xfer(data, reg, &val, 1);
125 if (ret < 0)
126 return ret;
127
128 return val;
129}
130
131static inline int lidar_write_control(struct lidar_data *data, int val)
132{
133 return i2c_smbus_write_byte_data(data->client, LIDAR_REG_CONTROL, val);
134}
135
136static inline int lidar_write_power(struct lidar_data *data, int val)
137{
138 return i2c_smbus_write_byte_data(data->client,
139 LIDAR_REG_PWR_CONTROL, val);
140}
141
142static int lidar_read_measurement(struct lidar_data *data, u16 *reg)
143{
144 __be16 value;
145 int ret = data->xfer(data, LIDAR_REG_DATA_HBYTE |
146 (data->i2c_enabled ? LIDAR_REG_DATA_WORD_READ : 0),
147 (u8 *) &value, 2);
148
149 if (!ret)
150 *reg = be16_to_cpu(value);
151
152 return ret;
153}
154
155static int lidar_get_measurement(struct lidar_data *data, u16 *reg)
156{
157 struct i2c_client *client = data->client;
158 int tries = 10;
159 int ret;
160
161 ret = pm_runtime_resume_and_get(&client->dev);
162 if (ret < 0)
163 return ret;
164
165
166 ret = lidar_write_control(data, LIDAR_REG_CONTROL_ACQUIRE);
167 if (ret < 0) {
168 dev_err(&client->dev, "cannot send start measurement command");
169 pm_runtime_put_noidle(&client->dev);
170 return ret;
171 }
172
173 while (tries--) {
174 usleep_range(1000, 2000);
175
176 ret = lidar_read_byte(data, LIDAR_REG_STATUS);
177 if (ret < 0)
178 break;
179
180
181 if (ret & LIDAR_REG_STATUS_INVALID) {
182 *reg = 0;
183 ret = -EINVAL;
184 break;
185 }
186
187
188 if (!(ret & LIDAR_REG_STATUS_READY)) {
189 ret = lidar_read_measurement(data, reg);
190 break;
191 }
192 ret = -EIO;
193 }
194 pm_runtime_mark_last_busy(&client->dev);
195 pm_runtime_put_autosuspend(&client->dev);
196
197 return ret;
198}
199
200static int lidar_read_raw(struct iio_dev *indio_dev,
201 struct iio_chan_spec const *chan,
202 int *val, int *val2, long mask)
203{
204 struct lidar_data *data = iio_priv(indio_dev);
205 int ret = -EINVAL;
206
207 switch (mask) {
208 case IIO_CHAN_INFO_RAW: {
209 u16 reg;
210
211 if (iio_device_claim_direct_mode(indio_dev))
212 return -EBUSY;
213
214 ret = lidar_get_measurement(data, ®);
215 if (!ret) {
216 *val = reg;
217 ret = IIO_VAL_INT;
218 }
219 iio_device_release_direct_mode(indio_dev);
220 break;
221 }
222 case IIO_CHAN_INFO_SCALE:
223 *val = 0;
224 *val2 = 10000;
225 ret = IIO_VAL_INT_PLUS_MICRO;
226 break;
227 }
228
229 return ret;
230}
231
232static irqreturn_t lidar_trigger_handler(int irq, void *private)
233{
234 struct iio_poll_func *pf = private;
235 struct iio_dev *indio_dev = pf->indio_dev;
236 struct lidar_data *data = iio_priv(indio_dev);
237 int ret;
238
239 ret = lidar_get_measurement(data, &data->scan.chan);
240 if (!ret) {
241 iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
242 iio_get_time_ns(indio_dev));
243 } else if (ret != -EINVAL) {
244 dev_err(&data->client->dev, "cannot read LIDAR measurement");
245 }
246
247 iio_trigger_notify_done(indio_dev->trig);
248
249 return IRQ_HANDLED;
250}
251
252static const struct iio_info lidar_info = {
253 .read_raw = lidar_read_raw,
254};
255
256static int lidar_probe(struct i2c_client *client,
257 const struct i2c_device_id *id)
258{
259 struct lidar_data *data;
260 struct iio_dev *indio_dev;
261 int ret;
262
263 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
264 if (!indio_dev)
265 return -ENOMEM;
266 data = iio_priv(indio_dev);
267
268 if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
269 data->xfer = lidar_i2c_xfer;
270 data->i2c_enabled = 1;
271 } else if (i2c_check_functionality(client->adapter,
272 I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_BYTE))
273 data->xfer = lidar_smbus_xfer;
274 else
275 return -EOPNOTSUPP;
276
277 indio_dev->info = &lidar_info;
278 indio_dev->name = LIDAR_DRV_NAME;
279 indio_dev->channels = lidar_channels;
280 indio_dev->num_channels = ARRAY_SIZE(lidar_channels);
281 indio_dev->modes = INDIO_DIRECT_MODE;
282
283 i2c_set_clientdata(client, indio_dev);
284
285 data->client = client;
286 data->indio_dev = indio_dev;
287
288 ret = iio_triggered_buffer_setup(indio_dev, NULL,
289 lidar_trigger_handler, NULL);
290 if (ret)
291 return ret;
292
293 ret = iio_device_register(indio_dev);
294 if (ret)
295 goto error_unreg_buffer;
296
297 pm_runtime_set_autosuspend_delay(&client->dev, 1000);
298 pm_runtime_use_autosuspend(&client->dev);
299
300 ret = pm_runtime_set_active(&client->dev);
301 if (ret)
302 goto error_unreg_buffer;
303 pm_runtime_enable(&client->dev);
304 pm_runtime_idle(&client->dev);
305
306 return 0;
307
308error_unreg_buffer:
309 iio_triggered_buffer_cleanup(indio_dev);
310
311 return ret;
312}
313
314static int lidar_remove(struct i2c_client *client)
315{
316 struct iio_dev *indio_dev = i2c_get_clientdata(client);
317
318 iio_device_unregister(indio_dev);
319 iio_triggered_buffer_cleanup(indio_dev);
320
321 pm_runtime_disable(&client->dev);
322 pm_runtime_set_suspended(&client->dev);
323
324 return 0;
325}
326
327static const struct i2c_device_id lidar_id[] = {
328 {"lidar-lite-v2", 0},
329 {"lidar-lite-v3", 0},
330 { },
331};
332MODULE_DEVICE_TABLE(i2c, lidar_id);
333
334static const struct of_device_id lidar_dt_ids[] = {
335 { .compatible = "pulsedlight,lidar-lite-v2" },
336 { .compatible = "grmn,lidar-lite-v3" },
337 { }
338};
339MODULE_DEVICE_TABLE(of, lidar_dt_ids);
340
341#ifdef CONFIG_PM
342static int lidar_pm_runtime_suspend(struct device *dev)
343{
344 struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
345 struct lidar_data *data = iio_priv(indio_dev);
346
347 return lidar_write_power(data, 0x0f);
348}
349
350static int lidar_pm_runtime_resume(struct device *dev)
351{
352 struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
353 struct lidar_data *data = iio_priv(indio_dev);
354 int ret = lidar_write_power(data, 0);
355
356
357 usleep_range(15000, 20000);
358
359 return ret;
360}
361#endif
362
363static const struct dev_pm_ops lidar_pm_ops = {
364 SET_RUNTIME_PM_OPS(lidar_pm_runtime_suspend,
365 lidar_pm_runtime_resume, NULL)
366};
367
368static struct i2c_driver lidar_driver = {
369 .driver = {
370 .name = LIDAR_DRV_NAME,
371 .of_match_table = lidar_dt_ids,
372 .pm = &lidar_pm_ops,
373 },
374 .probe = lidar_probe,
375 .remove = lidar_remove,
376 .id_table = lidar_id,
377};
378module_i2c_driver(lidar_driver);
379
380MODULE_AUTHOR("Matt Ranostay <matt.ranostay@konsulko.com>");
381MODULE_DESCRIPTION("PulsedLight LIDAR sensor");
382MODULE_LICENSE("GPL");
383
