1 /*
2 * MPU3050 Tri-axis gyroscope driver
3 *
4 * Copyright (C) 2011 Wistron Co.Ltd
5 * Joseph Lai <joseph_lai@wistron.com>
6 *
7 * Trimmed down by Alan Cox <alan@linux.intel.com> to produce this version
8 *
9 * This is a 'lite' version of the driver, while we consider the right way
10 * to present the other features to user space. In particular it requires the
11 * device has an IRQ, and it only provides an input interface, so is not much
12 * use for device orientation. A fuller version is available from the Meego
13 * tree.
14 *
15 * This program is based on bma023.c.
16 *
17 * This program is free software; you can redistribute it and/or modify
18 * it under the terms of the GNU General Public License as published by
19 * the Free Software Foundation; version 2 of the License.
20 *
21 * This program is distributed in the hope that it will be useful, but
22 * WITHOUT ANY WARRANTY; without even the implied warranty of
23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
24 * General Public License for more details.
25 *
26 * You should have received a copy of the GNU General Public License along
27 * with this program; if not, write to the Free Software Foundation, Inc.,
28 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
29 *
30 */
31
32 #include <linux/module.h>
33 #include <linux/init.h>
34 #include <linux/interrupt.h>
35 #include <linux/platform_device.h>
36 #include <linux/mutex.h>
37 #include <linux/err.h>
38 #include <linux/i2c.h>
39 #include <linux/input.h>
40 #include <linux/delay.h>
41 #include <linux/slab.h>
42 #include <linux/pm_runtime.h>
43
44 #define MPU3050_CHIP_ID 0x69
45
46 #define MPU3050_AUTO_DELAY 1000
47
48 #define MPU3050_MIN_VALUE -32768
49 #define MPU3050_MAX_VALUE 32767
50
51 #define MPU3050_DEFAULT_POLL_INTERVAL 200
52 #define MPU3050_DEFAULT_FS_RANGE 3
53
54 /* Register map */
55 #define MPU3050_CHIP_ID_REG 0x00
56 #define MPU3050_SMPLRT_DIV 0x15
57 #define MPU3050_DLPF_FS_SYNC 0x16
58 #define MPU3050_INT_CFG 0x17
59 #define MPU3050_XOUT_H 0x1D
60 #define MPU3050_PWR_MGM 0x3E
61 #define MPU3050_PWR_MGM_POS 6
62
63 /* Register bits */
64
65 /* DLPF_FS_SYNC */
66 #define MPU3050_EXT_SYNC_NONE 0x00
67 #define MPU3050_EXT_SYNC_TEMP 0x20
68 #define MPU3050_EXT_SYNC_GYROX 0x40
69 #define MPU3050_EXT_SYNC_GYROY 0x60
70 #define MPU3050_EXT_SYNC_GYROZ 0x80
71 #define MPU3050_EXT_SYNC_ACCELX 0xA0
72 #define MPU3050_EXT_SYNC_ACCELY 0xC0
73 #define MPU3050_EXT_SYNC_ACCELZ 0xE0
74 #define MPU3050_EXT_SYNC_MASK 0xE0
75 #define MPU3050_FS_250DPS 0x00
76 #define MPU3050_FS_500DPS 0x08
77 #define MPU3050_FS_1000DPS 0x10
78 #define MPU3050_FS_2000DPS 0x18
79 #define MPU3050_FS_MASK 0x18
80 #define MPU3050_DLPF_CFG_256HZ_NOLPF2 0x00
81 #define MPU3050_DLPF_CFG_188HZ 0x01
82 #define MPU3050_DLPF_CFG_98HZ 0x02
83 #define MPU3050_DLPF_CFG_42HZ 0x03
84 #define MPU3050_DLPF_CFG_20HZ 0x04
85 #define MPU3050_DLPF_CFG_10HZ 0x05
86 #define MPU3050_DLPF_CFG_5HZ 0x06
87 #define MPU3050_DLPF_CFG_2100HZ_NOLPF 0x07
88 #define MPU3050_DLPF_CFG_MASK 0x07
89 /* INT_CFG */
90 #define MPU3050_RAW_RDY_EN 0x01
91 #define MPU3050_MPU_RDY_EN 0x02
92 #define MPU3050_LATCH_INT_EN 0x04
93 /* PWR_MGM */
94 #define MPU3050_PWR_MGM_PLL_X 0x01
95 #define MPU3050_PWR_MGM_PLL_Y 0x02
96 #define MPU3050_PWR_MGM_PLL_Z 0x03
97 #define MPU3050_PWR_MGM_CLKSEL 0x07
98 #define MPU3050_PWR_MGM_STBY_ZG 0x08
99 #define MPU3050_PWR_MGM_STBY_YG 0x10
100 #define MPU3050_PWR_MGM_STBY_XG 0x20
101 #define MPU3050_PWR_MGM_SLEEP 0x40
102 #define MPU3050_PWR_MGM_RESET 0x80
103 #define MPU3050_PWR_MGM_MASK 0x40
104
105 struct axis_data {
106 s16 x;
107 s16 y;
108 s16 z;
109 };
110
111 struct mpu3050_sensor {
112 struct i2c_client *client;
113 struct device *dev;
114 struct input_dev *idev;
115 };
116
117 /**
118 * mpu3050_xyz_read_reg - read the axes values
119 * @buffer: provide register addr and get register
120 * @length: length of register
121 *
122 * Reads the register values in one transaction or returns a negative
123 * error code on failure.
124 */
mpu3050_xyz_read_reg(struct i2c_client * client,u8 * buffer,int length)125 static int mpu3050_xyz_read_reg(struct i2c_client *client,
126 u8 *buffer, int length)
127 {
128 /*
129 * Annoying we can't make this const because the i2c layer doesn't
130 * declare input buffers const.
131 */
132 char cmd = MPU3050_XOUT_H;
133 struct i2c_msg msg[] = {
134 {
135 .addr = client->addr,
136 .flags = 0,
137 .len = 1,
138 .buf = &cmd,
139 },
140 {
141 .addr = client->addr,
142 .flags = I2C_M_RD,
143 .len = length,
144 .buf = buffer,
145 },
146 };
147
148 return i2c_transfer(client->adapter, msg, 2);
149 }
150
151 /**
152 * mpu3050_read_xyz - get co-ordinates from device
153 * @client: i2c address of sensor
154 * @coords: co-ordinates to update
155 *
156 * Return the converted X Y and Z co-ordinates from the sensor device
157 */
mpu3050_read_xyz(struct i2c_client * client,struct axis_data * coords)158 static void mpu3050_read_xyz(struct i2c_client *client,
159 struct axis_data *coords)
160 {
161 u16 buffer[3];
162
163 mpu3050_xyz_read_reg(client, (u8 *)buffer, 6);
164 coords->x = be16_to_cpu(buffer[0]);
165 coords->y = be16_to_cpu(buffer[1]);
166 coords->z = be16_to_cpu(buffer[2]);
167 dev_dbg(&client->dev, "%s: x %d, y %d, z %d\n", __func__,
168 coords->x, coords->y, coords->z);
169 }
170
171 /**
172 * mpu3050_set_power_mode - set the power mode
173 * @client: i2c client for the sensor
174 * @val: value to switch on/off of power, 1: normal power, 0: low power
175 *
176 * Put device to normal-power mode or low-power mode.
177 */
mpu3050_set_power_mode(struct i2c_client * client,u8 val)178 static void mpu3050_set_power_mode(struct i2c_client *client, u8 val)
179 {
180 u8 value;
181
182 value = i2c_smbus_read_byte_data(client, MPU3050_PWR_MGM);
183 value = (value & ~MPU3050_PWR_MGM_MASK) |
184 (((val << MPU3050_PWR_MGM_POS) & MPU3050_PWR_MGM_MASK) ^
185 MPU3050_PWR_MGM_MASK);
186 i2c_smbus_write_byte_data(client, MPU3050_PWR_MGM, value);
187 }
188
189 /**
190 * mpu3050_input_open - called on input event open
191 * @input: input dev of opened device
192 *
193 * The input layer calls this function when input event is opened. The
194 * function will push the device to resume. Then, the device is ready
195 * to provide data.
196 */
mpu3050_input_open(struct input_dev * input)197 static int mpu3050_input_open(struct input_dev *input)
198 {
199 struct mpu3050_sensor *sensor = input_get_drvdata(input);
200 int error;
201
202 pm_runtime_get(sensor->dev);
203
204 /* Enable interrupts */
205 error = i2c_smbus_write_byte_data(sensor->client, MPU3050_INT_CFG,
206 MPU3050_LATCH_INT_EN |
207 MPU3050_RAW_RDY_EN |
208 MPU3050_MPU_RDY_EN);
209 if (error < 0) {
210 pm_runtime_put(sensor->dev);
211 return error;
212 }
213
214 return 0;
215 }
216
217 /**
218 * mpu3050_input_close - called on input event close
219 * @input: input dev of closed device
220 *
221 * The input layer calls this function when input event is closed. The
222 * function will push the device to suspend.
223 */
mpu3050_input_close(struct input_dev * input)224 static void mpu3050_input_close(struct input_dev *input)
225 {
226 struct mpu3050_sensor *sensor = input_get_drvdata(input);
227
228 pm_runtime_put(sensor->dev);
229 }
230
231 /**
232 * mpu3050_interrupt_thread - handle an IRQ
233 * @irq: interrupt numner
234 * @data: the sensor
235 *
236 * Called by the kernel single threaded after an interrupt occurs. Read
237 * the sensor data and generate an input event for it.
238 */
mpu3050_interrupt_thread(int irq,void * data)239 static irqreturn_t mpu3050_interrupt_thread(int irq, void *data)
240 {
241 struct mpu3050_sensor *sensor = data;
242 struct axis_data axis;
243
244 mpu3050_read_xyz(sensor->client, &axis);
245
246 input_report_abs(sensor->idev, ABS_X, axis.x);
247 input_report_abs(sensor->idev, ABS_Y, axis.y);
248 input_report_abs(sensor->idev, ABS_Z, axis.z);
249 input_sync(sensor->idev);
250
251 return IRQ_HANDLED;
252 }
253
254 /**
255 * mpu3050_hw_init - initialize hardware
256 * @sensor: the sensor
257 *
258 * Called during device probe; configures the sampling method.
259 */
mpu3050_hw_init(struct mpu3050_sensor * sensor)260 static int __devinit mpu3050_hw_init(struct mpu3050_sensor *sensor)
261 {
262 struct i2c_client *client = sensor->client;
263 int ret;
264 u8 reg;
265
266 /* Reset */
267 ret = i2c_smbus_write_byte_data(client, MPU3050_PWR_MGM,
268 MPU3050_PWR_MGM_RESET);
269 if (ret < 0)
270 return ret;
271
272 ret = i2c_smbus_read_byte_data(client, MPU3050_PWR_MGM);
273 if (ret < 0)
274 return ret;
275
276 ret &= ~MPU3050_PWR_MGM_CLKSEL;
277 ret |= MPU3050_PWR_MGM_PLL_Z;
278 ret = i2c_smbus_write_byte_data(client, MPU3050_PWR_MGM, ret);
279 if (ret < 0)
280 return ret;
281
282 /* Output frequency divider. The poll interval */
283 ret = i2c_smbus_write_byte_data(client, MPU3050_SMPLRT_DIV,
284 MPU3050_DEFAULT_POLL_INTERVAL - 1);
285 if (ret < 0)
286 return ret;
287
288 /* Set low pass filter and full scale */
289 reg = MPU3050_DEFAULT_FS_RANGE;
290 reg |= MPU3050_DLPF_CFG_42HZ << 3;
291 reg |= MPU3050_EXT_SYNC_NONE << 5;
292 ret = i2c_smbus_write_byte_data(client, MPU3050_DLPF_FS_SYNC, reg);
293 if (ret < 0)
294 return ret;
295
296 return 0;
297 }
298
299 /**
300 * mpu3050_probe - device detection callback
301 * @client: i2c client of found device
302 * @id: id match information
303 *
304 * The I2C layer calls us when it believes a sensor is present at this
305 * address. Probe to see if this is correct and to validate the device.
306 *
307 * If present install the relevant sysfs interfaces and input device.
308 */
mpu3050_probe(struct i2c_client * client,const struct i2c_device_id * id)309 static int __devinit mpu3050_probe(struct i2c_client *client,
310 const struct i2c_device_id *id)
311 {
312 struct mpu3050_sensor *sensor;
313 struct input_dev *idev;
314 int ret;
315 int error;
316
317 sensor = kzalloc(sizeof(struct mpu3050_sensor), GFP_KERNEL);
318 idev = input_allocate_device();
319 if (!sensor || !idev) {
320 dev_err(&client->dev, "failed to allocate driver data\n");
321 error = -ENOMEM;
322 goto err_free_mem;
323 }
324
325 sensor->client = client;
326 sensor->dev = &client->dev;
327 sensor->idev = idev;
328
329 mpu3050_set_power_mode(client, 1);
330 msleep(10);
331
332 ret = i2c_smbus_read_byte_data(client, MPU3050_CHIP_ID_REG);
333 if (ret < 0) {
334 dev_err(&client->dev, "failed to detect device\n");
335 error = -ENXIO;
336 goto err_free_mem;
337 }
338
339 if (ret != MPU3050_CHIP_ID) {
340 dev_err(&client->dev, "unsupported chip id\n");
341 error = -ENXIO;
342 goto err_free_mem;
343 }
344
345 idev->name = "MPU3050";
346 idev->id.bustype = BUS_I2C;
347 idev->dev.parent = &client->dev;
348
349 idev->open = mpu3050_input_open;
350 idev->close = mpu3050_input_close;
351
352 __set_bit(EV_ABS, idev->evbit);
353 input_set_abs_params(idev, ABS_X,
354 MPU3050_MIN_VALUE, MPU3050_MAX_VALUE, 0, 0);
355 input_set_abs_params(idev, ABS_Y,
356 MPU3050_MIN_VALUE, MPU3050_MAX_VALUE, 0, 0);
357 input_set_abs_params(idev, ABS_Z,
358 MPU3050_MIN_VALUE, MPU3050_MAX_VALUE, 0, 0);
359
360 input_set_drvdata(idev, sensor);
361
362 pm_runtime_set_active(&client->dev);
363
364 error = mpu3050_hw_init(sensor);
365 if (error)
366 goto err_pm_set_suspended;
367
368 error = request_threaded_irq(client->irq,
369 NULL, mpu3050_interrupt_thread,
370 IRQF_TRIGGER_RISING,
371 "mpu3050", sensor);
372 if (error) {
373 dev_err(&client->dev,
374 "can't get IRQ %d, error %d\n", client->irq, error);
375 goto err_pm_set_suspended;
376 }
377
378 error = input_register_device(idev);
379 if (error) {
380 dev_err(&client->dev, "failed to register input device\n");
381 goto err_free_irq;
382 }
383
384 pm_runtime_enable(&client->dev);
385 pm_runtime_set_autosuspend_delay(&client->dev, MPU3050_AUTO_DELAY);
386
387 return 0;
388
389 err_free_irq:
390 free_irq(client->irq, sensor);
391 err_pm_set_suspended:
392 pm_runtime_set_suspended(&client->dev);
393 err_free_mem:
394 input_free_device(idev);
395 kfree(sensor);
396 return error;
397 }
398
399 /**
400 * mpu3050_remove - remove a sensor
401 * @client: i2c client of sensor being removed
402 *
403 * Our sensor is going away, clean up the resources.
404 */
mpu3050_remove(struct i2c_client * client)405 static int __devexit mpu3050_remove(struct i2c_client *client)
406 {
407 struct mpu3050_sensor *sensor = i2c_get_clientdata(client);
408
409 pm_runtime_disable(&client->dev);
410 pm_runtime_set_suspended(&client->dev);
411
412 free_irq(client->irq, sensor);
413 input_unregister_device(sensor->idev);
414 kfree(sensor);
415
416 return 0;
417 }
418
419 #ifdef CONFIG_PM
420 /**
421 * mpu3050_suspend - called on device suspend
422 * @dev: device being suspended
423 *
424 * Put the device into sleep mode before we suspend the machine.
425 */
mpu3050_suspend(struct device * dev)426 static int mpu3050_suspend(struct device *dev)
427 {
428 struct i2c_client *client = to_i2c_client(dev);
429
430 mpu3050_set_power_mode(client, 0);
431
432 return 0;
433 }
434
435 /**
436 * mpu3050_resume - called on device resume
437 * @dev: device being resumed
438 *
439 * Put the device into powered mode on resume.
440 */
mpu3050_resume(struct device * dev)441 static int mpu3050_resume(struct device *dev)
442 {
443 struct i2c_client *client = to_i2c_client(dev);
444
445 mpu3050_set_power_mode(client, 1);
446 msleep(100); /* wait for gyro chip resume */
447
448 return 0;
449 }
450 #endif
451
452 static UNIVERSAL_DEV_PM_OPS(mpu3050_pm, mpu3050_suspend, mpu3050_resume, NULL);
453
454 static const struct i2c_device_id mpu3050_ids[] = {
455 { "mpu3050", 0 },
456 { }
457 };
458 MODULE_DEVICE_TABLE(i2c, mpu3050_ids);
459
460 static const struct of_device_id mpu3050_of_match[] = {
461 { .compatible = "invn,mpu3050", },
462 { },
463 };
464 MODULE_DEVICE_TABLE(of, mpu3050_of_match);
465
466 static struct i2c_driver mpu3050_i2c_driver = {
467 .driver = {
468 .name = "mpu3050",
469 .owner = THIS_MODULE,
470 .pm = &mpu3050_pm,
471 .of_match_table = mpu3050_of_match,
472 },
473 .probe = mpu3050_probe,
474 .remove = __devexit_p(mpu3050_remove),
475 .id_table = mpu3050_ids,
476 };
477
mpu3050_init(void)478 static int __init mpu3050_init(void)
479 {
480 return i2c_add_driver(&mpu3050_i2c_driver);
481 }
482 module_init(mpu3050_init);
483
mpu3050_exit(void)484 static void __exit mpu3050_exit(void)
485 {
486 i2c_del_driver(&mpu3050_i2c_driver);
487 }
488 module_exit(mpu3050_exit);
489
490 MODULE_AUTHOR("Wistron Corp.");
491 MODULE_DESCRIPTION("MPU3050 Tri-axis gyroscope driver");
492 MODULE_LICENSE("GPL");
493