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8#include <linux/kernel.h>
9#include <linux/leds.h>
10#include <linux/module.h>
11#include <linux/slab.h>
12#include <linux/jiffies.h>
13#include <linux/i2c.h>
14#include <linux/irq.h>
15#include <linux/interrupt.h>
16#include <linux/input.h>
17
18#define QT2160_VALID_CHIPID 0x11
19
20#define QT2160_CMD_CHIPID 0
21#define QT2160_CMD_CODEVER 1
22#define QT2160_CMD_GSTAT 2
23#define QT2160_CMD_KEYS3 3
24#define QT2160_CMD_KEYS4 4
25#define QT2160_CMD_SLIDE 5
26#define QT2160_CMD_GPIOS 6
27#define QT2160_CMD_SUBVER 7
28#define QT2160_CMD_CALIBRATE 10
29#define QT2160_CMD_DRIVE_X 70
30#define QT2160_CMD_PWMEN_X 74
31#define QT2160_CMD_PWM_DUTY 76
32
33#define QT2160_NUM_LEDS_X 8
34
35#define QT2160_CYCLE_INTERVAL (2*HZ)
36
37static unsigned char qt2160_key2code[] = {
38 KEY_0, KEY_1, KEY_2, KEY_3,
39 KEY_4, KEY_5, KEY_6, KEY_7,
40 KEY_8, KEY_9, KEY_A, KEY_B,
41 KEY_C, KEY_D, KEY_E, KEY_F,
42};
43
44#ifdef CONFIG_LEDS_CLASS
45struct qt2160_led {
46 struct qt2160_data *qt2160;
47 struct led_classdev cdev;
48 char name[32];
49 int id;
50 enum led_brightness brightness;
51};
52#endif
53
54struct qt2160_data {
55 struct i2c_client *client;
56 struct input_dev *input;
57 struct delayed_work dwork;
58 unsigned short keycodes[ARRAY_SIZE(qt2160_key2code)];
59 u16 key_matrix;
60#ifdef CONFIG_LEDS_CLASS
61 struct qt2160_led leds[QT2160_NUM_LEDS_X];
62#endif
63};
64
65static int qt2160_read(struct i2c_client *client, u8 reg);
66static int qt2160_write(struct i2c_client *client, u8 reg, u8 data);
67
68#ifdef CONFIG_LEDS_CLASS
69
70static int qt2160_led_set(struct led_classdev *cdev,
71 enum led_brightness value)
72{
73 struct qt2160_led *led = container_of(cdev, struct qt2160_led, cdev);
74 struct qt2160_data *qt2160 = led->qt2160;
75 struct i2c_client *client = qt2160->client;
76 u32 drive, pwmen;
77
78 if (value != led->brightness) {
79 drive = qt2160_read(client, QT2160_CMD_DRIVE_X);
80 pwmen = qt2160_read(client, QT2160_CMD_PWMEN_X);
81 if (value != LED_OFF) {
82 drive |= BIT(led->id);
83 pwmen |= BIT(led->id);
84
85 } else {
86 drive &= ~BIT(led->id);
87 pwmen &= ~BIT(led->id);
88 }
89 qt2160_write(client, QT2160_CMD_DRIVE_X, drive);
90 qt2160_write(client, QT2160_CMD_PWMEN_X, pwmen);
91
92
93
94
95
96 if (value != LED_OFF)
97 qt2160_write(client, QT2160_CMD_PWM_DUTY, value);
98
99 led->brightness = value;
100 }
101
102 return 0;
103}
104
105#endif
106
107static int qt2160_read_block(struct i2c_client *client,
108 u8 inireg, u8 *buffer, unsigned int count)
109{
110 int error, idx = 0;
111
112
113
114
115
116
117 if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
118
119 error = i2c_smbus_write_byte(client, inireg + idx);
120 if (error) {
121 dev_err(&client->dev,
122 "couldn't send request. Returned %d\n", error);
123 return error;
124 }
125
126 error = i2c_master_recv(client, buffer, count);
127 if (error != count) {
128 dev_err(&client->dev,
129 "couldn't read registers. Returned %d bytes\n", error);
130 return error;
131 }
132 } else {
133
134 while (count--) {
135 int data;
136
137 error = i2c_smbus_write_byte(client, inireg + idx);
138 if (error) {
139 dev_err(&client->dev,
140 "couldn't send request. Returned %d\n", error);
141 return error;
142 }
143
144 data = i2c_smbus_read_byte(client);
145 if (data < 0) {
146 dev_err(&client->dev,
147 "couldn't read register. Returned %d\n", data);
148 return data;
149 }
150
151 buffer[idx++] = data;
152 }
153 }
154
155 return 0;
156}
157
158static int qt2160_get_key_matrix(struct qt2160_data *qt2160)
159{
160 struct i2c_client *client = qt2160->client;
161 struct input_dev *input = qt2160->input;
162 u8 regs[6];
163 u16 old_matrix, new_matrix;
164 int ret, i, mask;
165
166 dev_dbg(&client->dev, "requesting keys...\n");
167
168
169
170
171
172 ret = qt2160_read_block(client, QT2160_CMD_GSTAT, regs, 6);
173 if (ret) {
174 dev_err(&client->dev,
175 "could not perform chip read.\n");
176 return ret;
177 }
178
179 old_matrix = qt2160->key_matrix;
180 qt2160->key_matrix = new_matrix = (regs[2] << 8) | regs[1];
181
182 mask = 0x01;
183 for (i = 0; i < 16; ++i, mask <<= 1) {
184 int keyval = new_matrix & mask;
185
186 if ((old_matrix & mask) != keyval) {
187 input_report_key(input, qt2160->keycodes[i], keyval);
188 dev_dbg(&client->dev, "key %d %s\n",
189 i, keyval ? "pressed" : "released");
190 }
191 }
192
193 input_sync(input);
194
195 return 0;
196}
197
198static irqreturn_t qt2160_irq(int irq, void *_qt2160)
199{
200 struct qt2160_data *qt2160 = _qt2160;
201
202 mod_delayed_work(system_wq, &qt2160->dwork, 0);
203
204 return IRQ_HANDLED;
205}
206
207static void qt2160_schedule_read(struct qt2160_data *qt2160)
208{
209 schedule_delayed_work(&qt2160->dwork, QT2160_CYCLE_INTERVAL);
210}
211
212static void qt2160_worker(struct work_struct *work)
213{
214 struct qt2160_data *qt2160 =
215 container_of(work, struct qt2160_data, dwork.work);
216
217 dev_dbg(&qt2160->client->dev, "worker\n");
218
219 qt2160_get_key_matrix(qt2160);
220
221
222 qt2160_schedule_read(qt2160);
223}
224
225static int qt2160_read(struct i2c_client *client, u8 reg)
226{
227 int ret;
228
229 ret = i2c_smbus_write_byte(client, reg);
230 if (ret) {
231 dev_err(&client->dev,
232 "couldn't send request. Returned %d\n", ret);
233 return ret;
234 }
235
236 ret = i2c_smbus_read_byte(client);
237 if (ret < 0) {
238 dev_err(&client->dev,
239 "couldn't read register. Returned %d\n", ret);
240 return ret;
241 }
242
243 return ret;
244}
245
246static int qt2160_write(struct i2c_client *client, u8 reg, u8 data)
247{
248 int ret;
249
250 ret = i2c_smbus_write_byte_data(client, reg, data);
251 if (ret < 0)
252 dev_err(&client->dev,
253 "couldn't write data. Returned %d\n", ret);
254
255 return ret;
256}
257
258#ifdef CONFIG_LEDS_CLASS
259
260static int qt2160_register_leds(struct qt2160_data *qt2160)
261{
262 struct i2c_client *client = qt2160->client;
263 int ret;
264 int i;
265
266 for (i = 0; i < QT2160_NUM_LEDS_X; i++) {
267 struct qt2160_led *led = &qt2160->leds[i];
268
269 snprintf(led->name, sizeof(led->name), "qt2160:x%d", i);
270 led->cdev.name = led->name;
271 led->cdev.brightness_set_blocking = qt2160_led_set;
272 led->cdev.brightness = LED_OFF;
273 led->id = i;
274 led->qt2160 = qt2160;
275
276 ret = led_classdev_register(&client->dev, &led->cdev);
277 if (ret < 0)
278 return ret;
279 }
280
281
282 qt2160_write(client, QT2160_CMD_DRIVE_X, 0);
283 qt2160_write(client, QT2160_CMD_PWMEN_X, 0);
284 qt2160_write(client, QT2160_CMD_PWM_DUTY, 0);
285
286 return 0;
287}
288
289static void qt2160_unregister_leds(struct qt2160_data *qt2160)
290{
291 int i;
292
293 for (i = 0; i < QT2160_NUM_LEDS_X; i++)
294 led_classdev_unregister(&qt2160->leds[i].cdev);
295}
296
297#else
298
299static inline int qt2160_register_leds(struct qt2160_data *qt2160)
300{
301 return 0;
302}
303
304static inline void qt2160_unregister_leds(struct qt2160_data *qt2160)
305{
306}
307
308#endif
309
310static bool qt2160_identify(struct i2c_client *client)
311{
312 int id, ver, rev;
313
314
315 id = qt2160_read(client, QT2160_CMD_CHIPID);
316 if (id != QT2160_VALID_CHIPID) {
317 dev_err(&client->dev, "ID %d not supported\n", id);
318 return false;
319 }
320
321
322 ver = qt2160_read(client, QT2160_CMD_CODEVER);
323 if (ver < 0) {
324 dev_err(&client->dev, "could not get firmware version\n");
325 return false;
326 }
327
328
329 rev = qt2160_read(client, QT2160_CMD_SUBVER);
330 if (rev < 0) {
331 dev_err(&client->dev, "could not get firmware revision\n");
332 return false;
333 }
334
335 dev_info(&client->dev, "AT42QT2160 firmware version %d.%d.%d\n",
336 ver >> 4, ver & 0xf, rev);
337
338 return true;
339}
340
341static int qt2160_probe(struct i2c_client *client,
342 const struct i2c_device_id *id)
343{
344 struct qt2160_data *qt2160;
345 struct input_dev *input;
346 int i;
347 int error;
348
349
350 error = i2c_check_functionality(client->adapter,
351 I2C_FUNC_SMBUS_BYTE);
352 if (!error) {
353 dev_err(&client->dev, "%s adapter not supported\n",
354 dev_driver_string(&client->adapter->dev));
355 return -ENODEV;
356 }
357
358 if (!qt2160_identify(client))
359 return -ENODEV;
360
361
362 qt2160 = kzalloc(sizeof(struct qt2160_data), GFP_KERNEL);
363 input = input_allocate_device();
364 if (!qt2160 || !input) {
365 dev_err(&client->dev, "insufficient memory\n");
366 error = -ENOMEM;
367 goto err_free_mem;
368 }
369
370 qt2160->client = client;
371 qt2160->input = input;
372 INIT_DELAYED_WORK(&qt2160->dwork, qt2160_worker);
373
374 input->name = "AT42QT2160 Touch Sense Keyboard";
375 input->id.bustype = BUS_I2C;
376
377 input->keycode = qt2160->keycodes;
378 input->keycodesize = sizeof(qt2160->keycodes[0]);
379 input->keycodemax = ARRAY_SIZE(qt2160_key2code);
380
381 __set_bit(EV_KEY, input->evbit);
382 __clear_bit(EV_REP, input->evbit);
383 for (i = 0; i < ARRAY_SIZE(qt2160_key2code); i++) {
384 qt2160->keycodes[i] = qt2160_key2code[i];
385 __set_bit(qt2160_key2code[i], input->keybit);
386 }
387 __clear_bit(KEY_RESERVED, input->keybit);
388
389
390 error = qt2160_write(client, QT2160_CMD_CALIBRATE, 1);
391 if (error) {
392 dev_err(&client->dev, "failed to calibrate device\n");
393 goto err_free_mem;
394 }
395
396 if (client->irq) {
397 error = request_irq(client->irq, qt2160_irq,
398 IRQF_TRIGGER_FALLING, "qt2160", qt2160);
399 if (error) {
400 dev_err(&client->dev,
401 "failed to allocate irq %d\n", client->irq);
402 goto err_free_mem;
403 }
404 }
405
406 error = qt2160_register_leds(qt2160);
407 if (error) {
408 dev_err(&client->dev, "Failed to register leds\n");
409 goto err_free_irq;
410 }
411
412 error = input_register_device(qt2160->input);
413 if (error) {
414 dev_err(&client->dev,
415 "Failed to register input device\n");
416 goto err_unregister_leds;
417 }
418
419 i2c_set_clientdata(client, qt2160);
420 qt2160_schedule_read(qt2160);
421
422 return 0;
423
424err_unregister_leds:
425 qt2160_unregister_leds(qt2160);
426err_free_irq:
427 if (client->irq)
428 free_irq(client->irq, qt2160);
429err_free_mem:
430 input_free_device(input);
431 kfree(qt2160);
432 return error;
433}
434
435static int qt2160_remove(struct i2c_client *client)
436{
437 struct qt2160_data *qt2160 = i2c_get_clientdata(client);
438
439 qt2160_unregister_leds(qt2160);
440
441
442 if (client->irq)
443 free_irq(client->irq, qt2160);
444
445 cancel_delayed_work_sync(&qt2160->dwork);
446
447 input_unregister_device(qt2160->input);
448 kfree(qt2160);
449
450 return 0;
451}
452
453static const struct i2c_device_id qt2160_idtable[] = {
454 { "qt2160", 0, },
455 { }
456};
457
458MODULE_DEVICE_TABLE(i2c, qt2160_idtable);
459
460static struct i2c_driver qt2160_driver = {
461 .driver = {
462 .name = "qt2160",
463 },
464
465 .id_table = qt2160_idtable,
466 .probe = qt2160_probe,
467 .remove = qt2160_remove,
468};
469
470module_i2c_driver(qt2160_driver);
471
472MODULE_AUTHOR("Raphael Derosso Pereira <raphaelpereira@gmail.com>");
473MODULE_DESCRIPTION("Driver for AT42QT2160 Touch Sensor");
474MODULE_LICENSE("GPL");
475
