This source file includes following definitions.
- imx_keypad_scan_matrix
- imx_keypad_fire_events
- imx_keypad_check_for_events
- imx_keypad_irq_handler
- imx_keypad_config
- imx_keypad_inhibit
- imx_keypad_close
- imx_keypad_open
- imx_keypad_probe
- imx_kbd_noirq_suspend
- imx_kbd_noirq_resume
1
2
3
4
5
6 #include <linux/clk.h>
7 #include <linux/delay.h>
8 #include <linux/device.h>
9 #include <linux/err.h>
10 #include <linux/input/matrix_keypad.h>
11 #include <linux/interrupt.h>
12 #include <linux/io.h>
13 #include <linux/jiffies.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/of.h>
17 #include <linux/platform_device.h>
18 #include <linux/slab.h>
19 #include <linux/timer.h>
20
21
22
23
24 #define KPCR 0x00
25
26 #define KPSR 0x02
27 #define KBD_STAT_KPKD (0x1 << 0)
28 #define KBD_STAT_KPKR (0x1 << 1)
29 #define KBD_STAT_KDSC (0x1 << 2)
30 #define KBD_STAT_KRSS (0x1 << 3)
31 #define KBD_STAT_KDIE (0x1 << 8)
32 #define KBD_STAT_KRIE (0x1 << 9)
33 #define KBD_STAT_KPPEN (0x1 << 10)
34
35 #define KDDR 0x04
36 #define KPDR 0x06
37
38 #define MAX_MATRIX_KEY_ROWS 8
39 #define MAX_MATRIX_KEY_COLS 8
40 #define MATRIX_ROW_SHIFT 3
41
42 #define MAX_MATRIX_KEY_NUM (MAX_MATRIX_KEY_ROWS * MAX_MATRIX_KEY_COLS)
43
44 struct imx_keypad {
45
46 struct clk *clk;
47 struct input_dev *input_dev;
48 void __iomem *mmio_base;
49
50 int irq;
51 struct timer_list check_matrix_timer;
52
53
54
55
56
57 #define IMX_KEYPAD_SCANS_FOR_STABILITY 3
58 int stable_count;
59
60 bool enabled;
61
62
63 unsigned short rows_en_mask;
64 unsigned short cols_en_mask;
65
66 unsigned short keycodes[MAX_MATRIX_KEY_NUM];
67
68
69
70
71
72
73 unsigned short matrix_stable_state[MAX_MATRIX_KEY_COLS];
74 unsigned short matrix_unstable_state[MAX_MATRIX_KEY_COLS];
75 };
76
77
78 static void imx_keypad_scan_matrix(struct imx_keypad *keypad,
79 unsigned short *matrix_volatile_state)
80 {
81 int col;
82 unsigned short reg_val;
83
84 for (col = 0; col < MAX_MATRIX_KEY_COLS; col++) {
85 if ((keypad->cols_en_mask & (1 << col)) == 0)
86 continue;
87
88
89
90
91
92
93 reg_val = readw(keypad->mmio_base + KPDR);
94 reg_val |= 0xff00;
95 writew(reg_val, keypad->mmio_base + KPDR);
96
97 reg_val = readw(keypad->mmio_base + KPCR);
98 reg_val &= ~((keypad->cols_en_mask & 0xff) << 8);
99 writew(reg_val, keypad->mmio_base + KPCR);
100
101 udelay(2);
102
103 reg_val = readw(keypad->mmio_base + KPCR);
104 reg_val |= (keypad->cols_en_mask & 0xff) << 8;
105 writew(reg_val, keypad->mmio_base + KPCR);
106
107
108
109
110
111
112 reg_val = readw(keypad->mmio_base + KPDR);
113 reg_val &= ~(1 << (8 + col));
114 writew(reg_val, keypad->mmio_base + KPDR);
115
116
117
118
119
120 udelay(5);
121
122
123
124
125
126 reg_val = readw(keypad->mmio_base + KPDR);
127 matrix_volatile_state[col] = (~reg_val) & keypad->rows_en_mask;
128 }
129
130
131
132
133
134 reg_val = readw(keypad->mmio_base + KPDR);
135 reg_val &= 0x00ff;
136 writew(reg_val, keypad->mmio_base + KPDR);
137 }
138
139
140
141
142
143 static void imx_keypad_fire_events(struct imx_keypad *keypad,
144 unsigned short *matrix_volatile_state)
145 {
146 struct input_dev *input_dev = keypad->input_dev;
147 int row, col;
148
149 for (col = 0; col < MAX_MATRIX_KEY_COLS; col++) {
150 unsigned short bits_changed;
151 int code;
152
153 if ((keypad->cols_en_mask & (1 << col)) == 0)
154 continue;
155
156 bits_changed = keypad->matrix_stable_state[col] ^
157 matrix_volatile_state[col];
158
159 if (bits_changed == 0)
160 continue;
161
162 for (row = 0; row < MAX_MATRIX_KEY_ROWS; row++) {
163 if ((keypad->rows_en_mask & (1 << row)) == 0)
164 continue;
165 if ((bits_changed & (1 << row)) == 0)
166 continue;
167
168 code = MATRIX_SCAN_CODE(row, col, MATRIX_ROW_SHIFT);
169 input_event(input_dev, EV_MSC, MSC_SCAN, code);
170 input_report_key(input_dev, keypad->keycodes[code],
171 matrix_volatile_state[col] & (1 << row));
172 dev_dbg(&input_dev->dev, "Event code: %d, val: %d",
173 keypad->keycodes[code],
174 matrix_volatile_state[col] & (1 << row));
175 }
176 }
177 input_sync(input_dev);
178 }
179
180
181
182
183 static void imx_keypad_check_for_events(struct timer_list *t)
184 {
185 struct imx_keypad *keypad = from_timer(keypad, t, check_matrix_timer);
186 unsigned short matrix_volatile_state[MAX_MATRIX_KEY_COLS];
187 unsigned short reg_val;
188 bool state_changed, is_zero_matrix;
189 int i;
190
191 memset(matrix_volatile_state, 0, sizeof(matrix_volatile_state));
192
193 imx_keypad_scan_matrix(keypad, matrix_volatile_state);
194
195 state_changed = false;
196 for (i = 0; i < MAX_MATRIX_KEY_COLS; i++) {
197 if ((keypad->cols_en_mask & (1 << i)) == 0)
198 continue;
199
200 if (keypad->matrix_unstable_state[i] ^ matrix_volatile_state[i]) {
201 state_changed = true;
202 break;
203 }
204 }
205
206
207
208
209
210
211
212
213 if (state_changed) {
214 memcpy(keypad->matrix_unstable_state, matrix_volatile_state,
215 sizeof(matrix_volatile_state));
216 keypad->stable_count = 0;
217 } else
218 keypad->stable_count++;
219
220
221
222
223
224 if (keypad->stable_count < IMX_KEYPAD_SCANS_FOR_STABILITY) {
225 mod_timer(&keypad->check_matrix_timer,
226 jiffies + msecs_to_jiffies(10));
227 return;
228 }
229
230
231
232
233
234
235
236 if (keypad->stable_count == IMX_KEYPAD_SCANS_FOR_STABILITY) {
237 imx_keypad_fire_events(keypad, matrix_volatile_state);
238
239 memcpy(keypad->matrix_stable_state, matrix_volatile_state,
240 sizeof(matrix_volatile_state));
241 }
242
243 is_zero_matrix = true;
244 for (i = 0; i < MAX_MATRIX_KEY_COLS; i++) {
245 if (matrix_volatile_state[i] != 0) {
246 is_zero_matrix = false;
247 break;
248 }
249 }
250
251
252 if (is_zero_matrix) {
253
254
255
256
257
258 reg_val = readw(keypad->mmio_base + KPSR);
259 reg_val |= KBD_STAT_KPKD | KBD_STAT_KDSC;
260 writew(reg_val, keypad->mmio_base + KPSR);
261
262 reg_val = readw(keypad->mmio_base + KPSR);
263 reg_val |= KBD_STAT_KDIE;
264 reg_val &= ~KBD_STAT_KRIE;
265 writew(reg_val, keypad->mmio_base + KPSR);
266 } else {
267
268
269
270
271
272
273 mod_timer(&keypad->check_matrix_timer,
274 jiffies + msecs_to_jiffies(60));
275
276 reg_val = readw(keypad->mmio_base + KPSR);
277 reg_val |= KBD_STAT_KPKR | KBD_STAT_KRSS;
278 writew(reg_val, keypad->mmio_base + KPSR);
279
280 reg_val = readw(keypad->mmio_base + KPSR);
281 reg_val |= KBD_STAT_KRIE;
282 reg_val &= ~KBD_STAT_KDIE;
283 writew(reg_val, keypad->mmio_base + KPSR);
284 }
285 }
286
287 static irqreturn_t imx_keypad_irq_handler(int irq, void *dev_id)
288 {
289 struct imx_keypad *keypad = dev_id;
290 unsigned short reg_val;
291
292 reg_val = readw(keypad->mmio_base + KPSR);
293
294
295 reg_val &= ~(KBD_STAT_KRIE | KBD_STAT_KDIE);
296
297 reg_val |= KBD_STAT_KPKR | KBD_STAT_KPKD;
298 writew(reg_val, keypad->mmio_base + KPSR);
299
300 if (keypad->enabled) {
301
302 keypad->stable_count = 0;
303
304
305 mod_timer(&keypad->check_matrix_timer,
306 jiffies + msecs_to_jiffies(2));
307 }
308
309 return IRQ_HANDLED;
310 }
311
312 static void imx_keypad_config(struct imx_keypad *keypad)
313 {
314 unsigned short reg_val;
315
316
317
318
319
320 reg_val = readw(keypad->mmio_base + KPCR);
321 reg_val |= keypad->rows_en_mask & 0xff;
322 reg_val |= (keypad->cols_en_mask & 0xff) << 8;
323 writew(reg_val, keypad->mmio_base + KPCR);
324
325
326 reg_val = readw(keypad->mmio_base + KPDR);
327 reg_val &= 0x00ff;
328 writew(reg_val, keypad->mmio_base + KPDR);
329
330
331 writew(0xff00, keypad->mmio_base + KDDR);
332
333
334
335
336
337 reg_val = readw(keypad->mmio_base + KPSR);
338 reg_val |= KBD_STAT_KPKR | KBD_STAT_KPKD |
339 KBD_STAT_KDSC | KBD_STAT_KRSS;
340 writew(reg_val, keypad->mmio_base + KPSR);
341
342
343 reg_val |= KBD_STAT_KDIE;
344 reg_val &= ~KBD_STAT_KRIE;
345 writew(reg_val, keypad->mmio_base + KPSR);
346 }
347
348 static void imx_keypad_inhibit(struct imx_keypad *keypad)
349 {
350 unsigned short reg_val;
351
352
353 reg_val = readw(keypad->mmio_base + KPSR);
354 reg_val &= ~(KBD_STAT_KRIE | KBD_STAT_KDIE);
355 reg_val |= KBD_STAT_KPKR | KBD_STAT_KPKD;
356 writew(reg_val, keypad->mmio_base + KPSR);
357
358
359 reg_val = (keypad->cols_en_mask & 0xff) << 8;
360 writew(reg_val, keypad->mmio_base + KPCR);
361 }
362
363 static void imx_keypad_close(struct input_dev *dev)
364 {
365 struct imx_keypad *keypad = input_get_drvdata(dev);
366
367 dev_dbg(&dev->dev, ">%s\n", __func__);
368
369
370 keypad->enabled = false;
371 synchronize_irq(keypad->irq);
372 del_timer_sync(&keypad->check_matrix_timer);
373
374 imx_keypad_inhibit(keypad);
375
376
377 clk_disable_unprepare(keypad->clk);
378 }
379
380 static int imx_keypad_open(struct input_dev *dev)
381 {
382 struct imx_keypad *keypad = input_get_drvdata(dev);
383 int error;
384
385 dev_dbg(&dev->dev, ">%s\n", __func__);
386
387
388 error = clk_prepare_enable(keypad->clk);
389 if (error)
390 return error;
391
392
393 keypad->enabled = true;
394
395 imx_keypad_config(keypad);
396
397
398 if ((readw(keypad->mmio_base + KPDR) & keypad->rows_en_mask) == 0) {
399 dev_err(&dev->dev,
400 "too many keys pressed, control pins initialisation\n");
401 goto open_err;
402 }
403
404 return 0;
405
406 open_err:
407 imx_keypad_close(dev);
408 return -EIO;
409 }
410
411 #ifdef CONFIG_OF
412 static const struct of_device_id imx_keypad_of_match[] = {
413 { .compatible = "fsl,imx21-kpp", },
414 { }
415 };
416 MODULE_DEVICE_TABLE(of, imx_keypad_of_match);
417 #endif
418
419 static int imx_keypad_probe(struct platform_device *pdev)
420 {
421 const struct matrix_keymap_data *keymap_data =
422 dev_get_platdata(&pdev->dev);
423 struct imx_keypad *keypad;
424 struct input_dev *input_dev;
425 int irq, error, i, row, col;
426
427 if (!keymap_data && !pdev->dev.of_node) {
428 dev_err(&pdev->dev, "no keymap defined\n");
429 return -EINVAL;
430 }
431
432 irq = platform_get_irq(pdev, 0);
433 if (irq < 0)
434 return irq;
435
436 input_dev = devm_input_allocate_device(&pdev->dev);
437 if (!input_dev) {
438 dev_err(&pdev->dev, "failed to allocate the input device\n");
439 return -ENOMEM;
440 }
441
442 keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad), GFP_KERNEL);
443 if (!keypad) {
444 dev_err(&pdev->dev, "not enough memory for driver data\n");
445 return -ENOMEM;
446 }
447
448 keypad->input_dev = input_dev;
449 keypad->irq = irq;
450 keypad->stable_count = 0;
451
452 timer_setup(&keypad->check_matrix_timer,
453 imx_keypad_check_for_events, 0);
454
455 keypad->mmio_base = devm_platform_ioremap_resource(pdev, 0);
456 if (IS_ERR(keypad->mmio_base))
457 return PTR_ERR(keypad->mmio_base);
458
459 keypad->clk = devm_clk_get(&pdev->dev, NULL);
460 if (IS_ERR(keypad->clk)) {
461 dev_err(&pdev->dev, "failed to get keypad clock\n");
462 return PTR_ERR(keypad->clk);
463 }
464
465
466 input_dev->name = pdev->name;
467 input_dev->id.bustype = BUS_HOST;
468 input_dev->dev.parent = &pdev->dev;
469 input_dev->open = imx_keypad_open;
470 input_dev->close = imx_keypad_close;
471
472 error = matrix_keypad_build_keymap(keymap_data, NULL,
473 MAX_MATRIX_KEY_ROWS,
474 MAX_MATRIX_KEY_COLS,
475 keypad->keycodes, input_dev);
476 if (error) {
477 dev_err(&pdev->dev, "failed to build keymap\n");
478 return error;
479 }
480
481
482 for (row = 0; row < MAX_MATRIX_KEY_ROWS; row++) {
483 for (col = 0; col < MAX_MATRIX_KEY_COLS; col++) {
484 i = MATRIX_SCAN_CODE(row, col, MATRIX_ROW_SHIFT);
485 if (keypad->keycodes[i] != KEY_RESERVED) {
486 keypad->rows_en_mask |= 1 << row;
487 keypad->cols_en_mask |= 1 << col;
488 }
489 }
490 }
491 dev_dbg(&pdev->dev, "enabled rows mask: %x\n", keypad->rows_en_mask);
492 dev_dbg(&pdev->dev, "enabled cols mask: %x\n", keypad->cols_en_mask);
493
494 __set_bit(EV_REP, input_dev->evbit);
495 input_set_capability(input_dev, EV_MSC, MSC_SCAN);
496 input_set_drvdata(input_dev, keypad);
497
498
499 error = clk_prepare_enable(keypad->clk);
500 if (error)
501 return error;
502 imx_keypad_inhibit(keypad);
503 clk_disable_unprepare(keypad->clk);
504
505 error = devm_request_irq(&pdev->dev, irq, imx_keypad_irq_handler, 0,
506 pdev->name, keypad);
507 if (error) {
508 dev_err(&pdev->dev, "failed to request IRQ\n");
509 return error;
510 }
511
512
513 error = input_register_device(input_dev);
514 if (error) {
515 dev_err(&pdev->dev, "failed to register input device\n");
516 return error;
517 }
518
519 platform_set_drvdata(pdev, keypad);
520 device_init_wakeup(&pdev->dev, 1);
521
522 return 0;
523 }
524
525 static int __maybe_unused imx_kbd_noirq_suspend(struct device *dev)
526 {
527 struct platform_device *pdev = to_platform_device(dev);
528 struct imx_keypad *kbd = platform_get_drvdata(pdev);
529 struct input_dev *input_dev = kbd->input_dev;
530 unsigned short reg_val = readw(kbd->mmio_base + KPSR);
531
532
533 mutex_lock(&input_dev->mutex);
534
535 if (input_dev->users)
536 clk_disable_unprepare(kbd->clk);
537
538 mutex_unlock(&input_dev->mutex);
539
540 if (device_may_wakeup(&pdev->dev)) {
541 if (reg_val & KBD_STAT_KPKD)
542 reg_val |= KBD_STAT_KRIE;
543 if (reg_val & KBD_STAT_KPKR)
544 reg_val |= KBD_STAT_KDIE;
545 writew(reg_val, kbd->mmio_base + KPSR);
546
547 enable_irq_wake(kbd->irq);
548 }
549
550 return 0;
551 }
552
553 static int __maybe_unused imx_kbd_noirq_resume(struct device *dev)
554 {
555 struct platform_device *pdev = to_platform_device(dev);
556 struct imx_keypad *kbd = platform_get_drvdata(pdev);
557 struct input_dev *input_dev = kbd->input_dev;
558 int ret = 0;
559
560 if (device_may_wakeup(&pdev->dev))
561 disable_irq_wake(kbd->irq);
562
563 mutex_lock(&input_dev->mutex);
564
565 if (input_dev->users) {
566 ret = clk_prepare_enable(kbd->clk);
567 if (ret)
568 goto err_clk;
569 }
570
571 err_clk:
572 mutex_unlock(&input_dev->mutex);
573
574 return ret;
575 }
576
577 static const struct dev_pm_ops imx_kbd_pm_ops = {
578 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx_kbd_noirq_suspend, imx_kbd_noirq_resume)
579 };
580
581 static struct platform_driver imx_keypad_driver = {
582 .driver = {
583 .name = "imx-keypad",
584 .pm = &imx_kbd_pm_ops,
585 .of_match_table = of_match_ptr(imx_keypad_of_match),
586 },
587 .probe = imx_keypad_probe,
588 };
589 module_platform_driver(imx_keypad_driver);
590
591 MODULE_AUTHOR("Alberto Panizzo <maramaopercheseimorto@gmail.com>");
592 MODULE_DESCRIPTION("IMX Keypad Port Driver");
593 MODULE_LICENSE("GPL v2");
594 MODULE_ALIAS("platform:imx-keypad");