1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * itg3200_core.c -- support InvenSense ITG3200
4 * Digital 3-Axis Gyroscope driver
5 *
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 filter
12 * - Support power management
13 */
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/delay.h>
22
23 #include <linux/iio/iio.h>
24 #include <linux/iio/sysfs.h>
25 #include <linux/iio/events.h>
26 #include <linux/iio/buffer.h>
27
28 #include <linux/iio/gyro/itg3200.h>
29
30
itg3200_write_reg_8(struct iio_dev * indio_dev,u8 reg_address,u8 val)31 int itg3200_write_reg_8(struct iio_dev *indio_dev,
32 u8 reg_address, u8 val)
33 {
34 struct itg3200 *st = iio_priv(indio_dev);
35
36 return i2c_smbus_write_byte_data(st->i2c, 0x80 | reg_address, val);
37 }
38
itg3200_read_reg_8(struct iio_dev * indio_dev,u8 reg_address,u8 * val)39 int itg3200_read_reg_8(struct iio_dev *indio_dev,
40 u8 reg_address, u8 *val)
41 {
42 struct itg3200 *st = iio_priv(indio_dev);
43 int ret;
44
45 ret = i2c_smbus_read_byte_data(st->i2c, reg_address);
46 if (ret < 0)
47 return ret;
48 *val = ret;
49 return 0;
50 }
51
itg3200_read_reg_s16(struct iio_dev * indio_dev,u8 lower_reg_address,int * val)52 static int itg3200_read_reg_s16(struct iio_dev *indio_dev, u8 lower_reg_address,
53 int *val)
54 {
55 struct itg3200 *st = iio_priv(indio_dev);
56 struct i2c_client *client = st->i2c;
57 int ret;
58 s16 out;
59
60 struct i2c_msg msg[2] = {
61 {
62 .addr = client->addr,
63 .flags = client->flags,
64 .len = 1,
65 .buf = (char *)&lower_reg_address,
66 },
67 {
68 .addr = client->addr,
69 .flags = client->flags | I2C_M_RD,
70 .len = 2,
71 .buf = (char *)&out,
72 },
73 };
74
75 lower_reg_address |= 0x80;
76 ret = i2c_transfer(client->adapter, msg, 2);
77 be16_to_cpus(&out);
78 *val = out;
79
80 return (ret == 2) ? 0 : ret;
81 }
82
itg3200_read_raw(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,int * val,int * val2,long info)83 static int itg3200_read_raw(struct iio_dev *indio_dev,
84 const struct iio_chan_spec *chan,
85 int *val, int *val2, long info)
86 {
87 int ret = 0;
88 u8 reg;
89 u8 regval;
90
91 switch (info) {
92 case IIO_CHAN_INFO_RAW:
93 reg = (u8)chan->address;
94 ret = itg3200_read_reg_s16(indio_dev, reg, val);
95 return IIO_VAL_INT;
96 case IIO_CHAN_INFO_SCALE:
97 *val = 0;
98 if (chan->type == IIO_TEMP)
99 *val2 = 1000000000/280;
100 else
101 *val2 = 1214142; /* (1 / 14,375) * (PI / 180) */
102 return IIO_VAL_INT_PLUS_NANO;
103 case IIO_CHAN_INFO_OFFSET:
104 /* Only the temperature channel has an offset */
105 *val = 23000;
106 return IIO_VAL_INT;
107 case IIO_CHAN_INFO_SAMP_FREQ:
108 ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_DLPF, ®val);
109 if (ret)
110 return ret;
111
112 *val = (regval & ITG3200_DLPF_CFG_MASK) ? 1000 : 8000;
113
114 ret = itg3200_read_reg_8(indio_dev,
115 ITG3200_REG_SAMPLE_RATE_DIV,
116 ®val);
117 if (ret)
118 return ret;
119
120 *val /= regval + 1;
121 return IIO_VAL_INT;
122
123 default:
124 return -EINVAL;
125 }
126 }
127
itg3200_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)128 static int itg3200_write_raw(struct iio_dev *indio_dev,
129 struct iio_chan_spec const *chan,
130 int val,
131 int val2,
132 long mask)
133 {
134 int ret;
135 u8 t;
136
137 switch (mask) {
138 case IIO_CHAN_INFO_SAMP_FREQ:
139 if (val == 0 || val2 != 0)
140 return -EINVAL;
141
142 mutex_lock(&indio_dev->mlock);
143
144 ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_DLPF, &t);
145 if (ret) {
146 mutex_unlock(&indio_dev->mlock);
147 return ret;
148 }
149 t = ((t & ITG3200_DLPF_CFG_MASK) ? 1000u : 8000u) / val - 1;
150
151 ret = itg3200_write_reg_8(indio_dev,
152 ITG3200_REG_SAMPLE_RATE_DIV,
153 t);
154
155 mutex_unlock(&indio_dev->mlock);
156 return ret;
157
158 default:
159 return -EINVAL;
160 }
161 }
162
163 /*
164 * Reset device and internal registers to the power-up-default settings
165 * Use the gyro clock as reference, as suggested by the datasheet
166 */
itg3200_reset(struct iio_dev * indio_dev)167 static int itg3200_reset(struct iio_dev *indio_dev)
168 {
169 struct itg3200 *st = iio_priv(indio_dev);
170 int ret;
171
172 dev_dbg(&st->i2c->dev, "reset device");
173
174 ret = itg3200_write_reg_8(indio_dev,
175 ITG3200_REG_POWER_MANAGEMENT,
176 ITG3200_RESET);
177 if (ret) {
178 dev_err(&st->i2c->dev, "error resetting device");
179 goto error_ret;
180 }
181
182 /* Wait for PLL (1ms according to datasheet) */
183 udelay(1500);
184
185 ret = itg3200_write_reg_8(indio_dev,
186 ITG3200_REG_IRQ_CONFIG,
187 ITG3200_IRQ_ACTIVE_HIGH |
188 ITG3200_IRQ_PUSH_PULL |
189 ITG3200_IRQ_LATCH_50US_PULSE |
190 ITG3200_IRQ_LATCH_CLEAR_ANY);
191
192 if (ret)
193 dev_err(&st->i2c->dev, "error init device");
194
195 error_ret:
196 return ret;
197 }
198
199 /* itg3200_enable_full_scale() - Disables the digital low pass filter */
itg3200_enable_full_scale(struct iio_dev * indio_dev)200 static int itg3200_enable_full_scale(struct iio_dev *indio_dev)
201 {
202 u8 val;
203 int ret;
204
205 ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_DLPF, &val);
206 if (ret)
207 goto err_ret;
208
209 val |= ITG3200_DLPF_FS_SEL_2000;
210 return itg3200_write_reg_8(indio_dev, ITG3200_REG_DLPF, val);
211
212 err_ret:
213 return ret;
214 }
215
itg3200_initial_setup(struct iio_dev * indio_dev)216 static int itg3200_initial_setup(struct iio_dev *indio_dev)
217 {
218 struct itg3200 *st = iio_priv(indio_dev);
219 int ret;
220 u8 val;
221
222 ret = itg3200_reset(indio_dev);
223 if (ret)
224 goto err_ret;
225
226 ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_ADDRESS, &val);
227 if (ret)
228 goto err_ret;
229
230 if (((val >> 1) & 0x3f) != 0x34) {
231 dev_err(&st->i2c->dev, "invalid reg value 0x%02x", val);
232 ret = -ENXIO;
233 goto err_ret;
234 }
235
236 ret = itg3200_enable_full_scale(indio_dev);
237 err_ret:
238 return ret;
239 }
240
241 static const struct iio_mount_matrix *
itg3200_get_mount_matrix(const struct iio_dev * indio_dev,const struct iio_chan_spec * chan)242 itg3200_get_mount_matrix(const struct iio_dev *indio_dev,
243 const struct iio_chan_spec *chan)
244 {
245 struct itg3200 *data = iio_priv(indio_dev);
246
247 return &data->orientation;
248 }
249
250 static const struct iio_chan_spec_ext_info itg3200_ext_info[] = {
251 IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, itg3200_get_mount_matrix),
252 { }
253 };
254
255 #define ITG3200_ST \
256 { .sign = 's', .realbits = 16, .storagebits = 16, .endianness = IIO_BE }
257
258 #define ITG3200_GYRO_CHAN(_mod) { \
259 .type = IIO_ANGL_VEL, \
260 .modified = 1, \
261 .channel2 = IIO_MOD_ ## _mod, \
262 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
263 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
264 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
265 .address = ITG3200_REG_GYRO_ ## _mod ## OUT_H, \
266 .scan_index = ITG3200_SCAN_GYRO_ ## _mod, \
267 .scan_type = ITG3200_ST, \
268 .ext_info = itg3200_ext_info, \
269 }
270
271 static const struct iio_chan_spec itg3200_channels[] = {
272 {
273 .type = IIO_TEMP,
274 .channel2 = IIO_NO_MOD,
275 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
276 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
277 BIT(IIO_CHAN_INFO_SCALE),
278 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
279 .address = ITG3200_REG_TEMP_OUT_H,
280 .scan_index = ITG3200_SCAN_TEMP,
281 .scan_type = ITG3200_ST,
282 },
283 ITG3200_GYRO_CHAN(X),
284 ITG3200_GYRO_CHAN(Y),
285 ITG3200_GYRO_CHAN(Z),
286 IIO_CHAN_SOFT_TIMESTAMP(ITG3200_SCAN_ELEMENTS),
287 };
288
289 static const struct iio_info itg3200_info = {
290 .read_raw = &itg3200_read_raw,
291 .write_raw = &itg3200_write_raw,
292 };
293
294 static const unsigned long itg3200_available_scan_masks[] = { 0xffffffff, 0x0 };
295
itg3200_probe(struct i2c_client * client,const struct i2c_device_id * id)296 static int itg3200_probe(struct i2c_client *client,
297 const struct i2c_device_id *id)
298 {
299 int ret;
300 struct itg3200 *st;
301 struct iio_dev *indio_dev;
302
303 dev_dbg(&client->dev, "probe I2C dev with IRQ %i", client->irq);
304
305 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));
306 if (!indio_dev)
307 return -ENOMEM;
308
309 st = iio_priv(indio_dev);
310
311 ret = iio_read_mount_matrix(&client->dev, &st->orientation);
312 if (ret)
313 return ret;
314
315 i2c_set_clientdata(client, indio_dev);
316 st->i2c = client;
317
318 indio_dev->name = client->dev.driver->name;
319 indio_dev->channels = itg3200_channels;
320 indio_dev->num_channels = ARRAY_SIZE(itg3200_channels);
321 indio_dev->available_scan_masks = itg3200_available_scan_masks;
322 indio_dev->info = &itg3200_info;
323 indio_dev->modes = INDIO_DIRECT_MODE;
324
325 ret = itg3200_buffer_configure(indio_dev);
326 if (ret)
327 return ret;
328
329 if (client->irq) {
330 ret = itg3200_probe_trigger(indio_dev);
331 if (ret)
332 goto error_unconfigure_buffer;
333 }
334
335 ret = itg3200_initial_setup(indio_dev);
336 if (ret)
337 goto error_remove_trigger;
338
339 ret = iio_device_register(indio_dev);
340 if (ret)
341 goto error_remove_trigger;
342
343 return 0;
344
345 error_remove_trigger:
346 if (client->irq)
347 itg3200_remove_trigger(indio_dev);
348 error_unconfigure_buffer:
349 itg3200_buffer_unconfigure(indio_dev);
350 return ret;
351 }
352
itg3200_remove(struct i2c_client * client)353 static int itg3200_remove(struct i2c_client *client)
354 {
355 struct iio_dev *indio_dev = i2c_get_clientdata(client);
356
357 iio_device_unregister(indio_dev);
358
359 if (client->irq)
360 itg3200_remove_trigger(indio_dev);
361
362 itg3200_buffer_unconfigure(indio_dev);
363
364 return 0;
365 }
366
itg3200_suspend(struct device * dev)367 static int __maybe_unused itg3200_suspend(struct device *dev)
368 {
369 struct iio_dev *indio_dev = dev_get_drvdata(dev);
370 struct itg3200 *st = iio_priv(indio_dev);
371
372 dev_dbg(&st->i2c->dev, "suspend device");
373
374 return itg3200_write_reg_8(indio_dev, ITG3200_REG_POWER_MANAGEMENT,
375 ITG3200_SLEEP);
376 }
377
itg3200_resume(struct device * dev)378 static int __maybe_unused itg3200_resume(struct device *dev)
379 {
380 struct iio_dev *indio_dev = dev_get_drvdata(dev);
381
382 return itg3200_initial_setup(indio_dev);
383 }
384
385 static SIMPLE_DEV_PM_OPS(itg3200_pm_ops, itg3200_suspend, itg3200_resume);
386
387 static const struct i2c_device_id itg3200_id[] = {
388 { "itg3200", 0 },
389 { }
390 };
391 MODULE_DEVICE_TABLE(i2c, itg3200_id);
392
393 static const struct of_device_id itg3200_of_match[] = {
394 { .compatible = "invensense,itg3200" },
395 { }
396 };
397 MODULE_DEVICE_TABLE(of, itg3200_of_match);
398
399 static struct i2c_driver itg3200_driver = {
400 .driver = {
401 .name = "itg3200",
402 .of_match_table = itg3200_of_match,
403 .pm = &itg3200_pm_ops,
404 },
405 .id_table = itg3200_id,
406 .probe = itg3200_probe,
407 .remove = itg3200_remove,
408 };
409
410 module_i2c_driver(itg3200_driver);
411
412 MODULE_AUTHOR("Christian Strobel <christian.strobel@iis.fraunhofer.de>");
413 MODULE_DESCRIPTION("ITG3200 Gyroscope I2C driver");
414 MODULE_LICENSE("GPL v2");
415