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/interrupt.h>
34 #include <linux/platform_device.h>
35 #include <linux/mutex.h>
36 #include <linux/err.h>
37 #include <linux/i2c.h>
38 #include <linux/input.h>
39 #include <linux/delay.h>
40 #include <linux/slab.h>
41 #include <linux/pm_runtime.h>
42
43 #define MPU3050_CHIP_ID 0x69
44
45 #define MPU3050_AUTO_DELAY 1000
46
47 #define MPU3050_MIN_VALUE -32768
48 #define MPU3050_MAX_VALUE 32767
49
50 #define MPU3050_DEFAULT_POLL_INTERVAL 200
51 #define MPU3050_DEFAULT_FS_RANGE 3
52
53 /* Register map */
54 #define MPU3050_CHIP_ID_REG 0x00
55 #define MPU3050_SMPLRT_DIV 0x15
56 #define MPU3050_DLPF_FS_SYNC 0x16
57 #define MPU3050_INT_CFG 0x17
58 #define MPU3050_XOUT_H 0x1D
59 #define MPU3050_PWR_MGM 0x3E
60 #define MPU3050_PWR_MGM_POS 6
61
62 /* Register bits */
63
64 /* DLPF_FS_SYNC */
65 #define MPU3050_EXT_SYNC_NONE 0x00
66 #define MPU3050_EXT_SYNC_TEMP 0x20
67 #define MPU3050_EXT_SYNC_GYROX 0x40
68 #define MPU3050_EXT_SYNC_GYROY 0x60
69 #define MPU3050_EXT_SYNC_GYROZ 0x80
70 #define MPU3050_EXT_SYNC_ACCELX 0xA0
71 #define MPU3050_EXT_SYNC_ACCELY 0xC0
72 #define MPU3050_EXT_SYNC_ACCELZ 0xE0
73 #define MPU3050_EXT_SYNC_MASK 0xE0
74 #define MPU3050_FS_250DPS 0x00
75 #define MPU3050_FS_500DPS 0x08
76 #define MPU3050_FS_1000DPS 0x10
77 #define MPU3050_FS_2000DPS 0x18
78 #define MPU3050_FS_MASK 0x18
79 #define MPU3050_DLPF_CFG_256HZ_NOLPF2 0x00
80 #define MPU3050_DLPF_CFG_188HZ 0x01
81 #define MPU3050_DLPF_CFG_98HZ 0x02
82 #define MPU3050_DLPF_CFG_42HZ 0x03
83 #define MPU3050_DLPF_CFG_20HZ 0x04
84 #define MPU3050_DLPF_CFG_10HZ 0x05
85 #define MPU3050_DLPF_CFG_5HZ 0x06
86 #define MPU3050_DLPF_CFG_2100HZ_NOLPF 0x07
87 #define MPU3050_DLPF_CFG_MASK 0x07
88 /* INT_CFG */
89 #define MPU3050_RAW_RDY_EN 0x01
90 #define MPU3050_MPU_RDY_EN 0x02
91 #define MPU3050_LATCH_INT_EN 0x04
92 /* PWR_MGM */
93 #define MPU3050_PWR_MGM_PLL_X 0x01
94 #define MPU3050_PWR_MGM_PLL_Y 0x02
95 #define MPU3050_PWR_MGM_PLL_Z 0x03
96 #define MPU3050_PWR_MGM_CLKSEL 0x07
97 #define MPU3050_PWR_MGM_STBY_ZG 0x08
98 #define MPU3050_PWR_MGM_STBY_YG 0x10
99 #define MPU3050_PWR_MGM_STBY_XG 0x20
100 #define MPU3050_PWR_MGM_SLEEP 0x40
101 #define MPU3050_PWR_MGM_RESET 0x80
102 #define MPU3050_PWR_MGM_MASK 0x40
103
104 struct axis_data {
105 s16 x;
106 s16 y;
107 s16 z;
108 };
109
110 struct mpu3050_sensor {
111 struct i2c_client *client;
112 struct device *dev;
113 struct input_dev *idev;
114 };
115
116 /**
117 * mpu3050_xyz_read_reg - read the axes values
118 * @buffer: provide register addr and get register
119 * @length: length of register
120 *
121 * Reads the register values in one transaction or returns a negative
122 * error code on failure.
123 */
mpu3050_xyz_read_reg(struct i2c_client * client,u8 * buffer,int length)124 static int mpu3050_xyz_read_reg(struct i2c_client *client,
125 u8 *buffer, int length)
126 {
127 /*
128 * Annoying we can't make this const because the i2c layer doesn't
129 * declare input buffers const.
130 */
131 char cmd = MPU3050_XOUT_H;
132 struct i2c_msg msg[] = {
133 {
134 .addr = client->addr,
135 .flags = 0,
136 .len = 1,
137 .buf = &cmd,
138 },
139 {
140 .addr = client->addr,
141 .flags = I2C_M_RD,
142 .len = length,
143 .buf = buffer,
144 },
145 };
146
147 return i2c_transfer(client->adapter, msg, 2);
148 }
149
150 /**
151 * mpu3050_read_xyz - get co-ordinates from device
152 * @client: i2c address of sensor
153 * @coords: co-ordinates to update
154 *
155 * Return the converted X Y and Z co-ordinates from the sensor device
156 */
mpu3050_read_xyz(struct i2c_client * client,struct axis_data * coords)157 static void mpu3050_read_xyz(struct i2c_client *client,
158 struct axis_data *coords)
159 {
160 u16 buffer[3];
161
162 mpu3050_xyz_read_reg(client, (u8 *)buffer, 6);
163 coords->x = be16_to_cpu(buffer[0]);
164 coords->y = be16_to_cpu(buffer[1]);
165 coords->z = be16_to_cpu(buffer[2]);
166 dev_dbg(&client->dev, "%s: x %d, y %d, z %d\n", __func__,
167 coords->x, coords->y, coords->z);
168 }
169
170 /**
171 * mpu3050_set_power_mode - set the power mode
172 * @client: i2c client for the sensor
173 * @val: value to switch on/off of power, 1: normal power, 0: low power
174 *
175 * Put device to normal-power mode or low-power mode.
176 */
mpu3050_set_power_mode(struct i2c_client * client,u8 val)177 static void mpu3050_set_power_mode(struct i2c_client *client, u8 val)
178 {
179 u8 value;
180
181 value = i2c_smbus_read_byte_data(client, MPU3050_PWR_MGM);
182 value = (value & ~MPU3050_PWR_MGM_MASK) |
183 (((val << MPU3050_PWR_MGM_POS) & MPU3050_PWR_MGM_MASK) ^
184 MPU3050_PWR_MGM_MASK);
185 i2c_smbus_write_byte_data(client, MPU3050_PWR_MGM, value);
186 }
187
188 /**
189 * mpu3050_input_open - called on input event open
190 * @input: input dev of opened device
191 *
192 * The input layer calls this function when input event is opened. The
193 * function will push the device to resume. Then, the device is ready
194 * to provide data.
195 */
mpu3050_input_open(struct input_dev * input)196 static int mpu3050_input_open(struct input_dev *input)
197 {
198 struct mpu3050_sensor *sensor = input_get_drvdata(input);
199 int error;
200
201 pm_runtime_get(sensor->dev);
202
203 /* Enable interrupts */
204 error = i2c_smbus_write_byte_data(sensor->client, MPU3050_INT_CFG,
205 MPU3050_LATCH_INT_EN |
206 MPU3050_RAW_RDY_EN |
207 MPU3050_MPU_RDY_EN);
208 if (error < 0) {
209 pm_runtime_put(sensor->dev);
210 return error;
211 }
212
213 return 0;
214 }
215
216 /**
217 * mpu3050_input_close - called on input event close
218 * @input: input dev of closed device
219 *
220 * The input layer calls this function when input event is closed. The
221 * function will push the device to suspend.
222 */
mpu3050_input_close(struct input_dev * input)223 static void mpu3050_input_close(struct input_dev *input)
224 {
225 struct mpu3050_sensor *sensor = input_get_drvdata(input);
226
227 pm_runtime_put(sensor->dev);
228 }
229
230 /**
231 * mpu3050_interrupt_thread - handle an IRQ
232 * @irq: interrupt numner
233 * @data: the sensor
234 *
235 * Called by the kernel single threaded after an interrupt occurs. Read
236 * the sensor data and generate an input event for it.
237 */
mpu3050_interrupt_thread(int irq,void * data)238 static irqreturn_t mpu3050_interrupt_thread(int irq, void *data)
239 {
240 struct mpu3050_sensor *sensor = data;
241 struct axis_data axis;
242
243 mpu3050_read_xyz(sensor->client, &axis);
244
245 input_report_abs(sensor->idev, ABS_X, axis.x);
246 input_report_abs(sensor->idev, ABS_Y, axis.y);
247 input_report_abs(sensor->idev, ABS_Z, axis.z);
248 input_sync(sensor->idev);
249
250 return IRQ_HANDLED;
251 }
252
253 /**
254 * mpu3050_hw_init - initialize hardware
255 * @sensor: the sensor
256 *
257 * Called during device probe; configures the sampling method.
258 */
mpu3050_hw_init(struct mpu3050_sensor * sensor)259 static int mpu3050_hw_init(struct mpu3050_sensor *sensor)
260 {
261 struct i2c_client *client = sensor->client;
262 int ret;
263 u8 reg;
264
265 /* Reset */
266 ret = i2c_smbus_write_byte_data(client, MPU3050_PWR_MGM,
267 MPU3050_PWR_MGM_RESET);
268 if (ret < 0)
269 return ret;
270
271 ret = i2c_smbus_read_byte_data(client, MPU3050_PWR_MGM);
272 if (ret < 0)
273 return ret;
274
275 ret &= ~MPU3050_PWR_MGM_CLKSEL;
276 ret |= MPU3050_PWR_MGM_PLL_Z;
277 ret = i2c_smbus_write_byte_data(client, MPU3050_PWR_MGM, ret);
278 if (ret < 0)
279 return ret;
280
281 /* Output frequency divider. The poll interval */
282 ret = i2c_smbus_write_byte_data(client, MPU3050_SMPLRT_DIV,
283 MPU3050_DEFAULT_POLL_INTERVAL - 1);
284 if (ret < 0)
285 return ret;
286
287 /* Set low pass filter and full scale */
288 reg = MPU3050_DEFAULT_FS_RANGE;
289 reg |= MPU3050_DLPF_CFG_42HZ << 3;
290 reg |= MPU3050_EXT_SYNC_NONE << 5;
291 ret = i2c_smbus_write_byte_data(client, MPU3050_DLPF_FS_SYNC, reg);
292 if (ret < 0)
293 return ret;
294
295 return 0;
296 }
297
298 /**
299 * mpu3050_probe - device detection callback
300 * @client: i2c client of found device
301 * @id: id match information
302 *
303 * The I2C layer calls us when it believes a sensor is present at this
304 * address. Probe to see if this is correct and to validate the device.
305 *
306 * If present install the relevant sysfs interfaces and input device.
307 */
mpu3050_probe(struct i2c_client * client,const struct i2c_device_id * id)308 static int mpu3050_probe(struct i2c_client *client,
309 const struct i2c_device_id *id)
310 {
311 struct mpu3050_sensor *sensor;
312 struct input_dev *idev;
313 int ret;
314 int error;
315
316 sensor = kzalloc(sizeof(struct mpu3050_sensor), GFP_KERNEL);
317 idev = input_allocate_device();
318 if (!sensor || !idev) {
319 dev_err(&client->dev, "failed to allocate driver data\n");
320 error = -ENOMEM;
321 goto err_free_mem;
322 }
323
324 sensor->client = client;
325 sensor->dev = &client->dev;
326 sensor->idev = idev;
327
328 mpu3050_set_power_mode(client, 1);
329 msleep(10);
330
331 ret = i2c_smbus_read_byte_data(client, MPU3050_CHIP_ID_REG);
332 if (ret < 0) {
333 dev_err(&client->dev, "failed to detect device\n");
334 error = -ENXIO;
335 goto err_free_mem;
336 }
337
338 if (ret != MPU3050_CHIP_ID) {
339 dev_err(&client->dev, "unsupported chip id\n");
340 error = -ENXIO;
341 goto err_free_mem;
342 }
343
344 idev->name = "MPU3050";
345 idev->id.bustype = BUS_I2C;
346 idev->dev.parent = &client->dev;
347
348 idev->open = mpu3050_input_open;
349 idev->close = mpu3050_input_close;
350
351 __set_bit(EV_ABS, idev->evbit);
352 input_set_abs_params(idev, ABS_X,
353 MPU3050_MIN_VALUE, MPU3050_MAX_VALUE, 0, 0);
354 input_set_abs_params(idev, ABS_Y,
355 MPU3050_MIN_VALUE, MPU3050_MAX_VALUE, 0, 0);
356 input_set_abs_params(idev, ABS_Z,
357 MPU3050_MIN_VALUE, MPU3050_MAX_VALUE, 0, 0);
358
359 input_set_drvdata(idev, sensor);
360
361 pm_runtime_set_active(&client->dev);
362
363 error = mpu3050_hw_init(sensor);
364 if (error)
365 goto err_pm_set_suspended;
366
367 error = request_threaded_irq(client->irq,
368 NULL, mpu3050_interrupt_thread,
369 IRQF_TRIGGER_RISING | IRQF_ONESHOT,
370 "mpu3050", sensor);
371 if (error) {
372 dev_err(&client->dev,
373 "can't get IRQ %d, error %d\n", client->irq, error);
374 goto err_pm_set_suspended;
375 }
376
377 error = input_register_device(idev);
378 if (error) {
379 dev_err(&client->dev, "failed to register input device\n");
380 goto err_free_irq;
381 }
382
383 pm_runtime_enable(&client->dev);
384 pm_runtime_set_autosuspend_delay(&client->dev, MPU3050_AUTO_DELAY);
385 i2c_set_clientdata(client, sensor);
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 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 .pm = &mpu3050_pm,
470 .of_match_table = mpu3050_of_match,
471 },
472 .probe = mpu3050_probe,
473 .remove = mpu3050_remove,
474 .id_table = mpu3050_ids,
475 };
476
477 module_i2c_driver(mpu3050_i2c_driver);
478
479 MODULE_AUTHOR("Wistron Corp.");
480 MODULE_DESCRIPTION("MPU3050 Tri-axis gyroscope driver");
481 MODULE_LICENSE("GPL");
482