1/*
2 * Copyright (C) 2011 Kionix, Inc.
3 * Written by Chris Hudson <chudson@kionix.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
17 * 02111-1307, USA
18 */
19
20#include <linux/delay.h>
21#include <linux/i2c.h>
22#include <linux/input.h>
23#include <linux/interrupt.h>
24#include <linux/module.h>
25#include <linux/slab.h>
26#include <linux/input/kxtj9.h>
27#include <linux/input-polldev.h>
28
29#define NAME "kxtj9"
30#define G_MAX 8000
31/* OUTPUT REGISTERS */
32#define XOUT_L 0x06
33#define WHO_AM_I 0x0F
34/* CONTROL REGISTERS */
35#define INT_REL 0x1A
36#define CTRL_REG1 0x1B
37#define INT_CTRL1 0x1E
38#define DATA_CTRL 0x21
39/* CONTROL REGISTER 1 BITS */
40#define PC1_OFF 0x7F
41#define PC1_ON (1 << 7)
42/* Data ready funtion enable bit: set during probe if using irq mode */
43#define DRDYE (1 << 5)
44/* DATA CONTROL REGISTER BITS */
45#define ODR12_5F 0
46#define ODR25F 1
47#define ODR50F 2
48#define ODR100F 3
49#define ODR200F 4
50#define ODR400F 5
51#define ODR800F 6
52/* INTERRUPT CONTROL REGISTER 1 BITS */
53/* Set these during probe if using irq mode */
54#define KXTJ9_IEL (1 << 3)
55#define KXTJ9_IEA (1 << 4)
56#define KXTJ9_IEN (1 << 5)
57/* INPUT_ABS CONSTANTS */
58#define FUZZ 3
59#define FLAT 3
60/* RESUME STATE INDICES */
61#define RES_DATA_CTRL 0
62#define RES_CTRL_REG1 1
63#define RES_INT_CTRL1 2
64#define RESUME_ENTRIES 3
65
66/*
67 * The following table lists the maximum appropriate poll interval for each
68 * available output data rate.
69 */
70static const struct {
71 unsigned int cutoff;
72 u8 mask;
73} kxtj9_odr_table[] = {
74 { 3, ODR800F },
75 { 5, ODR400F },
76 { 10, ODR200F },
77 { 20, ODR100F },
78 { 40, ODR50F },
79 { 80, ODR25F },
80 { 0, ODR12_5F},
81};
82
83struct kxtj9_data {
84 struct i2c_client *client;
85 struct kxtj9_platform_data pdata;
86 struct input_dev *input_dev;
87#ifdef CONFIG_INPUT_KXTJ9_POLLED_MODE
88 struct input_polled_dev *poll_dev;
89#endif
90 unsigned int last_poll_interval;
91 u8 shift;
92 u8 ctrl_reg1;
93 u8 data_ctrl;
94 u8 int_ctrl;
95};
96
97static int kxtj9_i2c_read(struct kxtj9_data *tj9, u8 addr, u8 *data, int len)
98{
99 struct i2c_msg msgs[] = {
100 {
101 .addr = tj9->client->addr,
102 .flags = tj9->client->flags,
103 .len = 1,
104 .buf = &addr,
105 },
106 {
107 .addr = tj9->client->addr,
108 .flags = tj9->client->flags | I2C_M_RD,
109 .len = len,
110 .buf = data,
111 },
112 };
113
114 return i2c_transfer(tj9->client->adapter, msgs, 2);
115}
116
117static void kxtj9_report_acceleration_data(struct kxtj9_data *tj9)
118{
119 s16 acc_data[3]; /* Data bytes from hardware xL, xH, yL, yH, zL, zH */
120 s16 x, y, z;
121 int err;
122
123 err = kxtj9_i2c_read(tj9, XOUT_L, (u8 *)acc_data, 6);
124 if (err < 0)
125 dev_err(&tj9->client->dev, "accelerometer data read failed\n");
126
127 x = le16_to_cpu(acc_data[tj9->pdata.axis_map_x]);
128 y = le16_to_cpu(acc_data[tj9->pdata.axis_map_y]);
129 z = le16_to_cpu(acc_data[tj9->pdata.axis_map_z]);
130
131 x >>= tj9->shift;
132 y >>= tj9->shift;
133 z >>= tj9->shift;
134
135 input_report_abs(tj9->input_dev, ABS_X, tj9->pdata.negate_x ? -x : x);
136 input_report_abs(tj9->input_dev, ABS_Y, tj9->pdata.negate_y ? -y : y);
137 input_report_abs(tj9->input_dev, ABS_Z, tj9->pdata.negate_z ? -z : z);
138 input_sync(tj9->input_dev);
139}
140
141static irqreturn_t kxtj9_isr(int irq, void *dev)
142{
143 struct kxtj9_data *tj9 = dev;
144 int err;
145
146 /* data ready is the only possible interrupt type */
147 kxtj9_report_acceleration_data(tj9);
148
149 err = i2c_smbus_read_byte_data(tj9->client, INT_REL);
150 if (err < 0)
151 dev_err(&tj9->client->dev,
152 "error clearing interrupt status: %d\n", err);
153
154 return IRQ_HANDLED;
155}
156
157static int kxtj9_update_g_range(struct kxtj9_data *tj9, u8 new_g_range)
158{
159 switch (new_g_range) {
160 case KXTJ9_G_2G:
161 tj9->shift = 4;
162 break;
163 case KXTJ9_G_4G:
164 tj9->shift = 3;
165 break;
166 case KXTJ9_G_8G:
167 tj9->shift = 2;
168 break;
169 default:
170 return -EINVAL;
171 }
172
173 tj9->ctrl_reg1 &= 0xe7;
174 tj9->ctrl_reg1 |= new_g_range;
175
176 return 0;
177}
178
179static int kxtj9_update_odr(struct kxtj9_data *tj9, unsigned int poll_interval)
180{
181 int err;
182 int i;
183
184 /* Use the lowest ODR that can support the requested poll interval */
185 for (i = 0; i < ARRAY_SIZE(kxtj9_odr_table); i++) {
186 tj9->data_ctrl = kxtj9_odr_table[i].mask;
187 if (poll_interval < kxtj9_odr_table[i].cutoff)
188 break;
189 }
190
191 err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, 0);
192 if (err < 0)
193 return err;
194
195 err = i2c_smbus_write_byte_data(tj9->client, DATA_CTRL, tj9->data_ctrl);
196 if (err < 0)
197 return err;
198
199 err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, tj9->ctrl_reg1);
200 if (err < 0)
201 return err;
202
203 return 0;
204}
205
206static int kxtj9_device_power_on(struct kxtj9_data *tj9)
207{
208 if (tj9->pdata.power_on)
209 return tj9->pdata.power_on();
210
211 return 0;
212}
213
214static void kxtj9_device_power_off(struct kxtj9_data *tj9)
215{
216 int err;
217
218 tj9->ctrl_reg1 &= PC1_OFF;
219 err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, tj9->ctrl_reg1);
220 if (err < 0)
221 dev_err(&tj9->client->dev, "soft power off failed\n");
222
223 if (tj9->pdata.power_off)
224 tj9->pdata.power_off();
225}
226
227static int kxtj9_enable(struct kxtj9_data *tj9)
228{
229 int err;
230
231 err = kxtj9_device_power_on(tj9);
232 if (err < 0)
233 return err;
234
235 /* ensure that PC1 is cleared before updating control registers */
236 err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, 0);
237 if (err < 0)
238 return err;
239
240 /* only write INT_CTRL_REG1 if in irq mode */
241 if (tj9->client->irq) {
242 err = i2c_smbus_write_byte_data(tj9->client,
243 INT_CTRL1, tj9->int_ctrl);
244 if (err < 0)
245 return err;
246 }
247
248 err = kxtj9_update_g_range(tj9, tj9->pdata.g_range);
249 if (err < 0)
250 return err;
251
252 /* turn on outputs */
253 tj9->ctrl_reg1 |= PC1_ON;
254 err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, tj9->ctrl_reg1);
255 if (err < 0)
256 return err;
257
258 err = kxtj9_update_odr(tj9, tj9->last_poll_interval);
259 if (err < 0)
260 return err;
261
262 /* clear initial interrupt if in irq mode */
263 if (tj9->client->irq) {
264 err = i2c_smbus_read_byte_data(tj9->client, INT_REL);
265 if (err < 0) {
266 dev_err(&tj9->client->dev,
267 "error clearing interrupt: %d\n", err);
268 goto fail;
269 }
270 }
271
272 return 0;
273
274fail:
275 kxtj9_device_power_off(tj9);
276 return err;
277}
278
279static void kxtj9_disable(struct kxtj9_data *tj9)
280{
281 kxtj9_device_power_off(tj9);
282}
283
284static int kxtj9_input_open(struct input_dev *input)
285{
286 struct kxtj9_data *tj9 = input_get_drvdata(input);
287
288 return kxtj9_enable(tj9);
289}
290
291static void kxtj9_input_close(struct input_dev *dev)
292{
293 struct kxtj9_data *tj9 = input_get_drvdata(dev);
294
295 kxtj9_disable(tj9);
296}
297
298static void kxtj9_init_input_device(struct kxtj9_data *tj9,
299 struct input_dev *input_dev)
300{
301 __set_bit(EV_ABS, input_dev->evbit);
302 input_set_abs_params(input_dev, ABS_X, -G_MAX, G_MAX, FUZZ, FLAT);
303 input_set_abs_params(input_dev, ABS_Y, -G_MAX, G_MAX, FUZZ, FLAT);
304 input_set_abs_params(input_dev, ABS_Z, -G_MAX, G_MAX, FUZZ, FLAT);
305
306 input_dev->name = "kxtj9_accel";
307 input_dev->id.bustype = BUS_I2C;
308 input_dev->dev.parent = &tj9->client->dev;
309}
310
311static int kxtj9_setup_input_device(struct kxtj9_data *tj9)
312{
313 struct input_dev *input_dev;
314 int err;
315
316 input_dev = input_allocate_device();
317 if (!input_dev) {
318 dev_err(&tj9->client->dev, "input device allocate failed\n");
319 return -ENOMEM;
320 }
321
322 tj9->input_dev = input_dev;
323
324 input_dev->open = kxtj9_input_open;
325 input_dev->close = kxtj9_input_close;
326 input_set_drvdata(input_dev, tj9);
327
328 kxtj9_init_input_device(tj9, input_dev);
329
330 err = input_register_device(tj9->input_dev);
331 if (err) {
332 dev_err(&tj9->client->dev,
333 "unable to register input polled device %s: %d\n",
334 tj9->input_dev->name, err);
335 input_free_device(tj9->input_dev);
336 return err;
337 }
338
339 return 0;
340}
341
342/*
343 * When IRQ mode is selected, we need to provide an interface to allow the user
344 * to change the output data rate of the part. For consistency, we are using
345 * the set_poll method, which accepts a poll interval in milliseconds, and then
346 * calls update_odr() while passing this value as an argument. In IRQ mode, the
347 * data outputs will not be read AT the requested poll interval, rather, the
348 * lowest ODR that can support the requested interval. The client application
349 * will be responsible for retrieving data from the input node at the desired
350 * interval.
351 */
352
353/* Returns currently selected poll interval (in ms) */
354static ssize_t kxtj9_get_poll(struct device *dev,
355 struct device_attribute *attr, char *buf)
356{
357 struct i2c_client *client = to_i2c_client(dev);
358 struct kxtj9_data *tj9 = i2c_get_clientdata(client);
359
360 return sprintf(buf, "%d\n", tj9->last_poll_interval);
361}
362
363/* Allow users to select a new poll interval (in ms) */
364static ssize_t kxtj9_set_poll(struct device *dev, struct device_attribute *attr,
365 const char *buf, size_t count)
366{
367 struct i2c_client *client = to_i2c_client(dev);
368 struct kxtj9_data *tj9 = i2c_get_clientdata(client);
369 struct input_dev *input_dev = tj9->input_dev;
370 unsigned int interval;
371 int error;
372
373 error = kstrtouint(buf, 10, &interval);
374 if (error < 0)
375 return error;
376
377 /* Lock the device to prevent races with open/close (and itself) */
378 mutex_lock(&input_dev->mutex);
379
380 disable_irq(client->irq);
381
382 /*
383 * Set current interval to the greater of the minimum interval or
384 * the requested interval
385 */
386 tj9->last_poll_interval = max(interval, tj9->pdata.min_interval);
387
388 kxtj9_update_odr(tj9, tj9->last_poll_interval);
389
390 enable_irq(client->irq);
391 mutex_unlock(&input_dev->mutex);
392
393 return count;
394}
395
396static DEVICE_ATTR(poll, S_IRUGO|S_IWUSR, kxtj9_get_poll, kxtj9_set_poll);
397
398static struct attribute *kxtj9_attributes[] = {
399 &dev_attr_poll.attr,
400 NULL
401};
402
403static struct attribute_group kxtj9_attribute_group = {
404 .attrs = kxtj9_attributes
405};
406
407
408#ifdef CONFIG_INPUT_KXTJ9_POLLED_MODE
409static void kxtj9_poll(struct input_polled_dev *dev)
410{
411 struct kxtj9_data *tj9 = dev->private;
412 unsigned int poll_interval = dev->poll_interval;
413
414 kxtj9_report_acceleration_data(tj9);
415
416 if (poll_interval != tj9->last_poll_interval) {
417 kxtj9_update_odr(tj9, poll_interval);
418 tj9->last_poll_interval = poll_interval;
419 }
420}
421
422static void kxtj9_polled_input_open(struct input_polled_dev *dev)
423{
424 struct kxtj9_data *tj9 = dev->private;
425
426 kxtj9_enable(tj9);
427}
428
429static void kxtj9_polled_input_close(struct input_polled_dev *dev)
430{
431 struct kxtj9_data *tj9 = dev->private;
432
433 kxtj9_disable(tj9);
434}
435
436static int kxtj9_setup_polled_device(struct kxtj9_data *tj9)
437{
438 int err;
439 struct input_polled_dev *poll_dev;
440 poll_dev = input_allocate_polled_device();
441
442 if (!poll_dev) {
443 dev_err(&tj9->client->dev,
444 "Failed to allocate polled device\n");
445 return -ENOMEM;
446 }
447
448 tj9->poll_dev = poll_dev;
449 tj9->input_dev = poll_dev->input;
450
451 poll_dev->private = tj9;
452 poll_dev->poll = kxtj9_poll;
453 poll_dev->open = kxtj9_polled_input_open;
454 poll_dev->close = kxtj9_polled_input_close;
455
456 kxtj9_init_input_device(tj9, poll_dev->input);
457
458 err = input_register_polled_device(poll_dev);
459 if (err) {
460 dev_err(&tj9->client->dev,
461 "Unable to register polled device, err=%d\n", err);
462 input_free_polled_device(poll_dev);
463 return err;
464 }
465
466 return 0;
467}
468
469static void kxtj9_teardown_polled_device(struct kxtj9_data *tj9)
470{
471 input_unregister_polled_device(tj9->poll_dev);
472 input_free_polled_device(tj9->poll_dev);
473}
474
475#else
476
477static inline int kxtj9_setup_polled_device(struct kxtj9_data *tj9)
478{
479 return -ENOSYS;
480}
481
482static inline void kxtj9_teardown_polled_device(struct kxtj9_data *tj9)
483{
484}
485
486#endif
487
488static int kxtj9_verify(struct kxtj9_data *tj9)
489{
490 int retval;
491
492 retval = kxtj9_device_power_on(tj9);
493 if (retval < 0)
494 return retval;
495
496 retval = i2c_smbus_read_byte_data(tj9->client, WHO_AM_I);
497 if (retval < 0) {
498 dev_err(&tj9->client->dev, "read err int source\n");
499 goto out;
500 }
501
502 retval = (retval != 0x07 && retval != 0x08) ? -EIO : 0;
503
504out:
505 kxtj9_device_power_off(tj9);
506 return retval;
507}
508
509static int kxtj9_probe(struct i2c_client *client,
510 const struct i2c_device_id *id)
511{
512 const struct kxtj9_platform_data *pdata =
513 dev_get_platdata(&client->dev);
514 struct kxtj9_data *tj9;
515 int err;
516
517 if (!i2c_check_functionality(client->adapter,
518 I2C_FUNC_I2C | I2C_FUNC_SMBUS_BYTE_DATA)) {
519 dev_err(&client->dev, "client is not i2c capable\n");
520 return -ENXIO;
521 }
522
523 if (!pdata) {
524 dev_err(&client->dev, "platform data is NULL; exiting\n");
525 return -EINVAL;
526 }
527
528 tj9 = kzalloc(sizeof(*tj9), GFP_KERNEL);
529 if (!tj9) {
530 dev_err(&client->dev,
531 "failed to allocate memory for module data\n");
532 return -ENOMEM;
533 }
534
535 tj9->client = client;
536 tj9->pdata = *pdata;
537
538 if (pdata->init) {
539 err = pdata->init();
540 if (err < 0)
541 goto err_free_mem;
542 }
543
544 err = kxtj9_verify(tj9);
545 if (err < 0) {
546 dev_err(&client->dev, "device not recognized\n");
547 goto err_pdata_exit;
548 }
549
550 i2c_set_clientdata(client, tj9);
551
552 tj9->ctrl_reg1 = tj9->pdata.res_12bit | tj9->pdata.g_range;
553 tj9->last_poll_interval = tj9->pdata.init_interval;
554
555 if (client->irq) {
556 /* If in irq mode, populate INT_CTRL_REG1 and enable DRDY. */
557 tj9->int_ctrl |= KXTJ9_IEN | KXTJ9_IEA | KXTJ9_IEL;
558 tj9->ctrl_reg1 |= DRDYE;
559
560 err = kxtj9_setup_input_device(tj9);
561 if (err)
562 goto err_pdata_exit;
563
564 err = request_threaded_irq(client->irq, NULL, kxtj9_isr,
565 IRQF_TRIGGER_RISING | IRQF_ONESHOT,
566 "kxtj9-irq", tj9);
567 if (err) {
568 dev_err(&client->dev, "request irq failed: %d\n", err);
569 goto err_destroy_input;
570 }
571
572 err = sysfs_create_group(&client->dev.kobj, &kxtj9_attribute_group);
573 if (err) {
574 dev_err(&client->dev, "sysfs create failed: %d\n", err);
575 goto err_free_irq;
576 }
577
578 } else {
579 err = kxtj9_setup_polled_device(tj9);
580 if (err)
581 goto err_pdata_exit;
582 }
583
584 return 0;
585
586err_free_irq:
587 free_irq(client->irq, tj9);
588err_destroy_input:
589 input_unregister_device(tj9->input_dev);
590err_pdata_exit:
591 if (tj9->pdata.exit)
592 tj9->pdata.exit();
593err_free_mem:
594 kfree(tj9);
595 return err;
596}
597
598static int kxtj9_remove(struct i2c_client *client)
599{
600 struct kxtj9_data *tj9 = i2c_get_clientdata(client);
601
602 if (client->irq) {
603 sysfs_remove_group(&client->dev.kobj, &kxtj9_attribute_group);
604 free_irq(client->irq, tj9);
605 input_unregister_device(tj9->input_dev);
606 } else {
607 kxtj9_teardown_polled_device(tj9);
608 }
609
610 if (tj9->pdata.exit)
611 tj9->pdata.exit();
612
613 kfree(tj9);
614
615 return 0;
616}
617
618static int __maybe_unused kxtj9_suspend(struct device *dev)
619{
620 struct i2c_client *client = to_i2c_client(dev);
621 struct kxtj9_data *tj9 = i2c_get_clientdata(client);
622 struct input_dev *input_dev = tj9->input_dev;
623
624 mutex_lock(&input_dev->mutex);
625
626 if (input_dev->users)
627 kxtj9_disable(tj9);
628
629 mutex_unlock(&input_dev->mutex);
630 return 0;
631}
632
633static int __maybe_unused kxtj9_resume(struct device *dev)
634{
635 struct i2c_client *client = to_i2c_client(dev);
636 struct kxtj9_data *tj9 = i2c_get_clientdata(client);
637 struct input_dev *input_dev = tj9->input_dev;
638
639 mutex_lock(&input_dev->mutex);
640
641 if (input_dev->users)
642 kxtj9_enable(tj9);
643
644 mutex_unlock(&input_dev->mutex);
645 return 0;
646}
647
648static SIMPLE_DEV_PM_OPS(kxtj9_pm_ops, kxtj9_suspend, kxtj9_resume);
649
650static const struct i2c_device_id kxtj9_id[] = {
651 { NAME, 0 },
652 { },
653};
654
655MODULE_DEVICE_TABLE(i2c, kxtj9_id);
656
657static struct i2c_driver kxtj9_driver = {
658 .driver = {
659 .name = NAME,
660 .pm = &kxtj9_pm_ops,
661 },
662 .probe = kxtj9_probe,
663 .remove = kxtj9_remove,
664 .id_table = kxtj9_id,
665};
666
667module_i2c_driver(kxtj9_driver);
668
669MODULE_DESCRIPTION("KXTJ9 accelerometer driver");
670MODULE_AUTHOR("Chris Hudson <chudson@kionix.com>");
671MODULE_LICENSE("GPL");
672