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21#include <linux/kernel.h>
22#include <linux/leds.h>
23#include <linux/module.h>
24#include <linux/slab.h>
25#include <linux/jiffies.h>
26#include <linux/i2c.h>
27#include <linux/irq.h>
28#include <linux/interrupt.h>
29#include <linux/input.h>
30
31#define QT2160_VALID_CHIPID 0x11
32
33#define QT2160_CMD_CHIPID 0
34#define QT2160_CMD_CODEVER 1
35#define QT2160_CMD_GSTAT 2
36#define QT2160_CMD_KEYS3 3
37#define QT2160_CMD_KEYS4 4
38#define QT2160_CMD_SLIDE 5
39#define QT2160_CMD_GPIOS 6
40#define QT2160_CMD_SUBVER 7
41#define QT2160_CMD_CALIBRATE 10
42#define QT2160_CMD_DRIVE_X 70
43#define QT2160_CMD_PWMEN_X 74
44#define QT2160_CMD_PWM_DUTY 76
45
46#define QT2160_NUM_LEDS_X 8
47
48#define QT2160_CYCLE_INTERVAL (2*HZ)
49
50static unsigned char qt2160_key2code[] = {
51 KEY_0, KEY_1, KEY_2, KEY_3,
52 KEY_4, KEY_5, KEY_6, KEY_7,
53 KEY_8, KEY_9, KEY_A, KEY_B,
54 KEY_C, KEY_D, KEY_E, KEY_F,
55};
56
57#ifdef CONFIG_LEDS_CLASS
58struct qt2160_led {
59 struct qt2160_data *qt2160;
60 struct led_classdev cdev;
61 struct work_struct work;
62 char name[32];
63 int id;
64 enum led_brightness new_brightness;
65};
66#endif
67
68struct qt2160_data {
69 struct i2c_client *client;
70 struct input_dev *input;
71 struct delayed_work dwork;
72 spinlock_t lock;
73 unsigned short keycodes[ARRAY_SIZE(qt2160_key2code)];
74 u16 key_matrix;
75#ifdef CONFIG_LEDS_CLASS
76 struct qt2160_led leds[QT2160_NUM_LEDS_X];
77 struct mutex led_lock;
78#endif
79};
80
81static int qt2160_read(struct i2c_client *client, u8 reg);
82static int qt2160_write(struct i2c_client *client, u8 reg, u8 data);
83
84#ifdef CONFIG_LEDS_CLASS
85
86static void qt2160_led_work(struct work_struct *work)
87{
88 struct qt2160_led *led = container_of(work, struct qt2160_led, work);
89 struct qt2160_data *qt2160 = led->qt2160;
90 struct i2c_client *client = qt2160->client;
91 int value = led->new_brightness;
92 u32 drive, pwmen;
93
94 mutex_lock(&qt2160->led_lock);
95
96 drive = qt2160_read(client, QT2160_CMD_DRIVE_X);
97 pwmen = qt2160_read(client, QT2160_CMD_PWMEN_X);
98 if (value != LED_OFF) {
99 drive |= (1 << led->id);
100 pwmen |= (1 << led->id);
101
102 } else {
103 drive &= ~(1 << led->id);
104 pwmen &= ~(1 << led->id);
105 }
106 qt2160_write(client, QT2160_CMD_DRIVE_X, drive);
107 qt2160_write(client, QT2160_CMD_PWMEN_X, pwmen);
108
109
110
111
112
113 if (value != LED_OFF)
114 qt2160_write(client, QT2160_CMD_PWM_DUTY, value);
115
116 mutex_unlock(&qt2160->led_lock);
117}
118
119static void qt2160_led_set(struct led_classdev *cdev,
120 enum led_brightness value)
121{
122 struct qt2160_led *led = container_of(cdev, struct qt2160_led, cdev);
123
124 led->new_brightness = value;
125 schedule_work(&led->work);
126}
127
128#endif
129
130static int qt2160_read_block(struct i2c_client *client,
131 u8 inireg, u8 *buffer, unsigned int count)
132{
133 int error, idx = 0;
134
135
136
137
138
139
140 if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
141
142 error = i2c_smbus_write_byte(client, inireg + idx);
143 if (error) {
144 dev_err(&client->dev,
145 "couldn't send request. Returned %d\n", error);
146 return error;
147 }
148
149 error = i2c_master_recv(client, buffer, count);
150 if (error != count) {
151 dev_err(&client->dev,
152 "couldn't read registers. Returned %d bytes\n", error);
153 return error;
154 }
155 } else {
156
157 while (count--) {
158 int data;
159
160 error = i2c_smbus_write_byte(client, inireg + idx);
161 if (error) {
162 dev_err(&client->dev,
163 "couldn't send request. Returned %d\n", error);
164 return error;
165 }
166
167 data = i2c_smbus_read_byte(client);
168 if (data < 0) {
169 dev_err(&client->dev,
170 "couldn't read register. Returned %d\n", data);
171 return data;
172 }
173
174 buffer[idx++] = data;
175 }
176 }
177
178 return 0;
179}
180
181static int qt2160_get_key_matrix(struct qt2160_data *qt2160)
182{
183 struct i2c_client *client = qt2160->client;
184 struct input_dev *input = qt2160->input;
185 u8 regs[6];
186 u16 old_matrix, new_matrix;
187 int ret, i, mask;
188
189 dev_dbg(&client->dev, "requesting keys...\n");
190
191
192
193
194
195 ret = qt2160_read_block(client, QT2160_CMD_GSTAT, regs, 6);
196 if (ret) {
197 dev_err(&client->dev,
198 "could not perform chip read.\n");
199 return ret;
200 }
201
202 old_matrix = qt2160->key_matrix;
203 qt2160->key_matrix = new_matrix = (regs[2] << 8) | regs[1];
204
205 mask = 0x01;
206 for (i = 0; i < 16; ++i, mask <<= 1) {
207 int keyval = new_matrix & mask;
208
209 if ((old_matrix & mask) != keyval) {
210 input_report_key(input, qt2160->keycodes[i], keyval);
211 dev_dbg(&client->dev, "key %d %s\n",
212 i, keyval ? "pressed" : "released");
213 }
214 }
215
216 input_sync(input);
217
218 return 0;
219}
220
221static irqreturn_t qt2160_irq(int irq, void *_qt2160)
222{
223 struct qt2160_data *qt2160 = _qt2160;
224 unsigned long flags;
225
226 spin_lock_irqsave(&qt2160->lock, flags);
227
228 mod_delayed_work(system_wq, &qt2160->dwork, 0);
229
230 spin_unlock_irqrestore(&qt2160->lock, flags);
231
232 return IRQ_HANDLED;
233}
234
235static void qt2160_schedule_read(struct qt2160_data *qt2160)
236{
237 spin_lock_irq(&qt2160->lock);
238 schedule_delayed_work(&qt2160->dwork, QT2160_CYCLE_INTERVAL);
239 spin_unlock_irq(&qt2160->lock);
240}
241
242static void qt2160_worker(struct work_struct *work)
243{
244 struct qt2160_data *qt2160 =
245 container_of(work, struct qt2160_data, dwork.work);
246
247 dev_dbg(&qt2160->client->dev, "worker\n");
248
249 qt2160_get_key_matrix(qt2160);
250
251
252 qt2160_schedule_read(qt2160);
253}
254
255static int qt2160_read(struct i2c_client *client, u8 reg)
256{
257 int ret;
258
259 ret = i2c_smbus_write_byte(client, reg);
260 if (ret) {
261 dev_err(&client->dev,
262 "couldn't send request. Returned %d\n", ret);
263 return ret;
264 }
265
266 ret = i2c_smbus_read_byte(client);
267 if (ret < 0) {
268 dev_err(&client->dev,
269 "couldn't read register. Returned %d\n", ret);
270 return ret;
271 }
272
273 return ret;
274}
275
276static int qt2160_write(struct i2c_client *client, u8 reg, u8 data)
277{
278 int ret;
279
280 ret = i2c_smbus_write_byte_data(client, reg, data);
281 if (ret < 0)
282 dev_err(&client->dev,
283 "couldn't write data. Returned %d\n", ret);
284
285 return ret;
286}
287
288#ifdef CONFIG_LEDS_CLASS
289
290static int qt2160_register_leds(struct qt2160_data *qt2160)
291{
292 struct i2c_client *client = qt2160->client;
293 int ret;
294 int i;
295
296 mutex_init(&qt2160->led_lock);
297
298 for (i = 0; i < QT2160_NUM_LEDS_X; i++) {
299 struct qt2160_led *led = &qt2160->leds[i];
300
301 snprintf(led->name, sizeof(led->name), "qt2160:x%d", i);
302 led->cdev.name = led->name;
303 led->cdev.brightness_set = qt2160_led_set;
304 led->cdev.brightness = LED_OFF;
305 led->id = i;
306 led->qt2160 = qt2160;
307
308 INIT_WORK(&led->work, qt2160_led_work);
309
310 ret = led_classdev_register(&client->dev, &led->cdev);
311 if (ret < 0)
312 return ret;
313 }
314
315
316 qt2160_write(client, QT2160_CMD_DRIVE_X, 0);
317 qt2160_write(client, QT2160_CMD_PWMEN_X, 0);
318 qt2160_write(client, QT2160_CMD_PWM_DUTY, 0);
319
320 return 0;
321}
322
323static void qt2160_unregister_leds(struct qt2160_data *qt2160)
324{
325 int i;
326
327 for (i = 0; i < QT2160_NUM_LEDS_X; i++) {
328 led_classdev_unregister(&qt2160->leds[i].cdev);
329 cancel_work_sync(&qt2160->leds[i].work);
330 }
331}
332
333#else
334
335static inline int qt2160_register_leds(struct qt2160_data *qt2160)
336{
337 return 0;
338}
339
340static inline void qt2160_unregister_leds(struct qt2160_data *qt2160)
341{
342}
343
344#endif
345
346static bool qt2160_identify(struct i2c_client *client)
347{
348 int id, ver, rev;
349
350
351 id = qt2160_read(client, QT2160_CMD_CHIPID);
352 if (id != QT2160_VALID_CHIPID) {
353 dev_err(&client->dev, "ID %d not supported\n", id);
354 return false;
355 }
356
357
358 ver = qt2160_read(client, QT2160_CMD_CODEVER);
359 if (ver < 0) {
360 dev_err(&client->dev, "could not get firmware version\n");
361 return false;
362 }
363
364
365 rev = qt2160_read(client, QT2160_CMD_SUBVER);
366 if (rev < 0) {
367 dev_err(&client->dev, "could not get firmware revision\n");
368 return false;
369 }
370
371 dev_info(&client->dev, "AT42QT2160 firmware version %d.%d.%d\n",
372 ver >> 4, ver & 0xf, rev);
373
374 return true;
375}
376
377static int qt2160_probe(struct i2c_client *client,
378 const struct i2c_device_id *id)
379{
380 struct qt2160_data *qt2160;
381 struct input_dev *input;
382 int i;
383 int error;
384
385
386 error = i2c_check_functionality(client->adapter,
387 I2C_FUNC_SMBUS_BYTE);
388 if (!error) {
389 dev_err(&client->dev, "%s adapter not supported\n",
390 dev_driver_string(&client->adapter->dev));
391 return -ENODEV;
392 }
393
394 if (!qt2160_identify(client))
395 return -ENODEV;
396
397
398 qt2160 = kzalloc(sizeof(struct qt2160_data), GFP_KERNEL);
399 input = input_allocate_device();
400 if (!qt2160 || !input) {
401 dev_err(&client->dev, "insufficient memory\n");
402 error = -ENOMEM;
403 goto err_free_mem;
404 }
405
406 qt2160->client = client;
407 qt2160->input = input;
408 INIT_DELAYED_WORK(&qt2160->dwork, qt2160_worker);
409 spin_lock_init(&qt2160->lock);
410
411 input->name = "AT42QT2160 Touch Sense Keyboard";
412 input->id.bustype = BUS_I2C;
413
414 input->keycode = qt2160->keycodes;
415 input->keycodesize = sizeof(qt2160->keycodes[0]);
416 input->keycodemax = ARRAY_SIZE(qt2160_key2code);
417
418 __set_bit(EV_KEY, input->evbit);
419 __clear_bit(EV_REP, input->evbit);
420 for (i = 0; i < ARRAY_SIZE(qt2160_key2code); i++) {
421 qt2160->keycodes[i] = qt2160_key2code[i];
422 __set_bit(qt2160_key2code[i], input->keybit);
423 }
424 __clear_bit(KEY_RESERVED, input->keybit);
425
426
427 error = qt2160_write(client, QT2160_CMD_CALIBRATE, 1);
428 if (error) {
429 dev_err(&client->dev, "failed to calibrate device\n");
430 goto err_free_mem;
431 }
432
433 if (client->irq) {
434 error = request_irq(client->irq, qt2160_irq,
435 IRQF_TRIGGER_FALLING, "qt2160", qt2160);
436 if (error) {
437 dev_err(&client->dev,
438 "failed to allocate irq %d\n", client->irq);
439 goto err_free_mem;
440 }
441 }
442
443 error = qt2160_register_leds(qt2160);
444 if (error) {
445 dev_err(&client->dev, "Failed to register leds\n");
446 goto err_free_irq;
447 }
448
449 error = input_register_device(qt2160->input);
450 if (error) {
451 dev_err(&client->dev,
452 "Failed to register input device\n");
453 goto err_unregister_leds;
454 }
455
456 i2c_set_clientdata(client, qt2160);
457 qt2160_schedule_read(qt2160);
458
459 return 0;
460
461err_unregister_leds:
462 qt2160_unregister_leds(qt2160);
463err_free_irq:
464 if (client->irq)
465 free_irq(client->irq, qt2160);
466err_free_mem:
467 input_free_device(input);
468 kfree(qt2160);
469 return error;
470}
471
472static int qt2160_remove(struct i2c_client *client)
473{
474 struct qt2160_data *qt2160 = i2c_get_clientdata(client);
475
476 qt2160_unregister_leds(qt2160);
477
478
479 if (client->irq)
480 free_irq(client->irq, qt2160);
481
482 cancel_delayed_work_sync(&qt2160->dwork);
483
484 input_unregister_device(qt2160->input);
485 kfree(qt2160);
486
487 return 0;
488}
489
490static const struct i2c_device_id qt2160_idtable[] = {
491 { "qt2160", 0, },
492 { }
493};
494
495MODULE_DEVICE_TABLE(i2c, qt2160_idtable);
496
497static struct i2c_driver qt2160_driver = {
498 .driver = {
499 .name = "qt2160",
500 },
501
502 .id_table = qt2160_idtable,
503 .probe = qt2160_probe,
504 .remove = qt2160_remove,
505};
506
507module_i2c_driver(qt2160_driver);
508
509MODULE_AUTHOR("Raphael Derosso Pereira <raphaelpereira@gmail.com>");
510MODULE_DESCRIPTION("Driver for AT42QT2160 Touch Sensor");
511MODULE_LICENSE("GPL");
512
