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18#include <linux/interrupt.h>
19#include <linux/irq.h>
20#include <linux/i2c.h>
21#include <linux/gpio.h>
22#include <linux/slab.h>
23#include <linux/stat.h>
24#include <linux/module.h>
25#include <linux/delay.h>
26
27#include <linux/iio/iio.h>
28#include <linux/iio/sysfs.h>
29#include <linux/iio/events.h>
30#include <linux/iio/buffer.h>
31
32#include <linux/iio/gyro/itg3200.h>
33
34
35int itg3200_write_reg_8(struct iio_dev *indio_dev,
36 u8 reg_address, u8 val)
37{
38 struct itg3200 *st = iio_priv(indio_dev);
39
40 return i2c_smbus_write_byte_data(st->i2c, 0x80 | reg_address, val);
41}
42
43int itg3200_read_reg_8(struct iio_dev *indio_dev,
44 u8 reg_address, u8 *val)
45{
46 struct itg3200 *st = iio_priv(indio_dev);
47 int ret;
48
49 ret = i2c_smbus_read_byte_data(st->i2c, reg_address);
50 if (ret < 0)
51 return ret;
52 *val = ret;
53 return 0;
54}
55
56static int itg3200_read_reg_s16(struct iio_dev *indio_dev, u8 lower_reg_address,
57 int *val)
58{
59 struct itg3200 *st = iio_priv(indio_dev);
60 struct i2c_client *client = st->i2c;
61 int ret;
62 s16 out;
63
64 struct i2c_msg msg[2] = {
65 {
66 .addr = client->addr,
67 .flags = client->flags,
68 .len = 1,
69 .buf = (char *)&lower_reg_address,
70 },
71 {
72 .addr = client->addr,
73 .flags = client->flags | I2C_M_RD,
74 .len = 2,
75 .buf = (char *)&out,
76 },
77 };
78
79 lower_reg_address |= 0x80;
80 ret = i2c_transfer(client->adapter, msg, 2);
81 be16_to_cpus(&out);
82 *val = out;
83
84 return (ret == 2) ? 0 : ret;
85}
86
87static int itg3200_read_raw(struct iio_dev *indio_dev,
88 const struct iio_chan_spec *chan,
89 int *val, int *val2, long info)
90{
91 int ret = 0;
92 u8 reg;
93
94 switch (info) {
95 case IIO_CHAN_INFO_RAW:
96 reg = (u8)chan->address;
97 ret = itg3200_read_reg_s16(indio_dev, reg, val);
98 return IIO_VAL_INT;
99 case IIO_CHAN_INFO_SCALE:
100 *val = 0;
101 if (chan->type == IIO_TEMP)
102 *val2 = 1000000000/280;
103 else
104 *val2 = 1214142;
105 return IIO_VAL_INT_PLUS_NANO;
106 case IIO_CHAN_INFO_OFFSET:
107
108 *val = 23000;
109 return IIO_VAL_INT;
110 default:
111 return -EINVAL;
112 }
113
114 return ret;
115}
116
117static ssize_t itg3200_read_frequency(struct device *dev,
118 struct device_attribute *attr, char *buf)
119{
120 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
121 int ret, sps;
122 u8 val;
123
124 ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_DLPF, &val);
125 if (ret)
126 return ret;
127
128 sps = (val & ITG3200_DLPF_CFG_MASK) ? 1000 : 8000;
129
130 ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_SAMPLE_RATE_DIV, &val);
131 if (ret)
132 return ret;
133
134 sps /= val + 1;
135
136 return sprintf(buf, "%d\n", sps);
137}
138
139static ssize_t itg3200_write_frequency(struct device *dev,
140 struct device_attribute *attr,
141 const char *buf,
142 size_t len)
143{
144 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
145 unsigned val;
146 int ret;
147 u8 t;
148
149 ret = kstrtouint(buf, 10, &val);
150 if (ret)
151 return ret;
152
153 mutex_lock(&indio_dev->mlock);
154
155 ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_DLPF, &t);
156 if (ret)
157 goto err_ret;
158
159 if (val == 0) {
160 ret = -EINVAL;
161 goto err_ret;
162 }
163 t = ((t & ITG3200_DLPF_CFG_MASK) ? 1000u : 8000u) / val - 1;
164
165 ret = itg3200_write_reg_8(indio_dev, ITG3200_REG_SAMPLE_RATE_DIV, t);
166
167err_ret:
168 mutex_unlock(&indio_dev->mlock);
169
170 return ret ? ret : len;
171}
172
173
174
175
176
177static int itg3200_reset(struct iio_dev *indio_dev)
178{
179 struct itg3200 *st = iio_priv(indio_dev);
180 int ret;
181
182 dev_dbg(&st->i2c->dev, "reset device");
183
184 ret = itg3200_write_reg_8(indio_dev,
185 ITG3200_REG_POWER_MANAGEMENT,
186 ITG3200_RESET);
187 if (ret) {
188 dev_err(&st->i2c->dev, "error resetting device");
189 goto error_ret;
190 }
191
192
193 udelay(1500);
194
195 ret = itg3200_write_reg_8(indio_dev,
196 ITG3200_REG_IRQ_CONFIG,
197 ITG3200_IRQ_ACTIVE_HIGH |
198 ITG3200_IRQ_PUSH_PULL |
199 ITG3200_IRQ_LATCH_50US_PULSE |
200 ITG3200_IRQ_LATCH_CLEAR_ANY);
201
202 if (ret)
203 dev_err(&st->i2c->dev, "error init device");
204
205error_ret:
206 return ret;
207}
208
209
210static int itg3200_enable_full_scale(struct iio_dev *indio_dev)
211{
212 u8 val;
213 int ret;
214
215 ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_DLPF, &val);
216 if (ret)
217 goto err_ret;
218
219 val |= ITG3200_DLPF_FS_SEL_2000;
220 return itg3200_write_reg_8(indio_dev, ITG3200_REG_DLPF, val);
221
222err_ret:
223 return ret;
224}
225
226static int itg3200_initial_setup(struct iio_dev *indio_dev)
227{
228 struct itg3200 *st = iio_priv(indio_dev);
229 int ret;
230 u8 val;
231
232 ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_ADDRESS, &val);
233 if (ret)
234 goto err_ret;
235
236 if (((val >> 1) & 0x3f) != 0x34) {
237 dev_err(&st->i2c->dev, "invalid reg value 0x%02x", val);
238 ret = -ENXIO;
239 goto err_ret;
240 }
241
242 ret = itg3200_reset(indio_dev);
243 if (ret)
244 goto err_ret;
245
246 ret = itg3200_enable_full_scale(indio_dev);
247err_ret:
248 return ret;
249}
250
251#define ITG3200_ST \
252 { .sign = 's', .realbits = 16, .storagebits = 16, .endianness = IIO_BE }
253
254#define ITG3200_GYRO_CHAN(_mod) { \
255 .type = IIO_ANGL_VEL, \
256 .modified = 1, \
257 .channel2 = IIO_MOD_ ## _mod, \
258 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
259 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
260 .address = ITG3200_REG_GYRO_ ## _mod ## OUT_H, \
261 .scan_index = ITG3200_SCAN_GYRO_ ## _mod, \
262 .scan_type = ITG3200_ST, \
263}
264
265static const struct iio_chan_spec itg3200_channels[] = {
266 {
267 .type = IIO_TEMP,
268 .channel2 = IIO_NO_MOD,
269 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
270 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
271 BIT(IIO_CHAN_INFO_SCALE),
272 .address = ITG3200_REG_TEMP_OUT_H,
273 .scan_index = ITG3200_SCAN_TEMP,
274 .scan_type = ITG3200_ST,
275 },
276 ITG3200_GYRO_CHAN(X),
277 ITG3200_GYRO_CHAN(Y),
278 ITG3200_GYRO_CHAN(Z),
279 IIO_CHAN_SOFT_TIMESTAMP(ITG3200_SCAN_ELEMENTS),
280};
281
282
283static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO, itg3200_read_frequency,
284 itg3200_write_frequency);
285
286static struct attribute *itg3200_attributes[] = {
287 &iio_dev_attr_sampling_frequency.dev_attr.attr,
288 NULL
289};
290
291static const struct attribute_group itg3200_attribute_group = {
292 .attrs = itg3200_attributes,
293};
294
295static const struct iio_info itg3200_info = {
296 .attrs = &itg3200_attribute_group,
297 .read_raw = &itg3200_read_raw,
298 .driver_module = THIS_MODULE,
299};
300
301static const unsigned long itg3200_available_scan_masks[] = { 0xffffffff, 0x0 };
302
303static int itg3200_probe(struct i2c_client *client,
304 const struct i2c_device_id *id)
305{
306 int ret;
307 struct itg3200 *st;
308 struct iio_dev *indio_dev;
309
310 dev_dbg(&client->dev, "probe I2C dev with IRQ %i", client->irq);
311
312 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));
313 if (!indio_dev)
314 return -ENOMEM;
315
316 st = iio_priv(indio_dev);
317
318 i2c_set_clientdata(client, indio_dev);
319 st->i2c = client;
320
321 indio_dev->dev.parent = &client->dev;
322 indio_dev->name = client->dev.driver->name;
323 indio_dev->channels = itg3200_channels;
324 indio_dev->num_channels = ARRAY_SIZE(itg3200_channels);
325 indio_dev->available_scan_masks = itg3200_available_scan_masks;
326 indio_dev->info = &itg3200_info;
327 indio_dev->modes = INDIO_DIRECT_MODE;
328
329 ret = itg3200_buffer_configure(indio_dev);
330 if (ret)
331 return ret;
332
333 if (client->irq) {
334 ret = itg3200_probe_trigger(indio_dev);
335 if (ret)
336 goto error_unconfigure_buffer;
337 }
338
339 ret = itg3200_initial_setup(indio_dev);
340 if (ret)
341 goto error_remove_trigger;
342
343 ret = iio_device_register(indio_dev);
344 if (ret)
345 goto error_remove_trigger;
346
347 return 0;
348
349error_remove_trigger:
350 if (client->irq)
351 itg3200_remove_trigger(indio_dev);
352error_unconfigure_buffer:
353 itg3200_buffer_unconfigure(indio_dev);
354 return ret;
355}
356
357static int itg3200_remove(struct i2c_client *client)
358{
359 struct iio_dev *indio_dev = i2c_get_clientdata(client);
360
361 iio_device_unregister(indio_dev);
362
363 if (client->irq)
364 itg3200_remove_trigger(indio_dev);
365
366 itg3200_buffer_unconfigure(indio_dev);
367
368 return 0;
369}
370
371static const struct i2c_device_id itg3200_id[] = {
372 { "itg3200", 0 },
373 { }
374};
375MODULE_DEVICE_TABLE(i2c, itg3200_id);
376
377static struct i2c_driver itg3200_driver = {
378 .driver = {
379 .owner = THIS_MODULE,
380 .name = "itg3200",
381 },
382 .id_table = itg3200_id,
383 .probe = itg3200_probe,
384 .remove = itg3200_remove,
385};
386
387module_i2c_driver(itg3200_driver);
388
389MODULE_AUTHOR("Christian Strobel <christian.strobel@iis.fraunhofer.de>");
390MODULE_DESCRIPTION("ITG3200 Gyroscope I2C driver");
391MODULE_LICENSE("GPL v2");
392
