1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * OMAP4 Keypad Driver
4 *
5 * Copyright (C) 2010 Texas Instruments
6 *
7 * Author: Abraham Arce <x0066660@ti.com>
8 * Initial Code: Syed Rafiuddin <rafiuddin.syed@ti.com>
9 */
10
11 #include <linux/module.h>
12 #include <linux/interrupt.h>
13 #include <linux/platform_device.h>
14 #include <linux/errno.h>
15 #include <linux/io.h>
16 #include <linux/of.h>
17 #include <linux/input.h>
18 #include <linux/input/matrix_keypad.h>
19 #include <linux/slab.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/pm_wakeirq.h>
22
23 /* OMAP4 registers */
24 #define OMAP4_KBD_REVISION 0x00
25 #define OMAP4_KBD_SYSCONFIG 0x10
26 #define OMAP4_KBD_SYSSTATUS 0x14
27 #define OMAP4_KBD_IRQSTATUS 0x18
28 #define OMAP4_KBD_IRQENABLE 0x1C
29 #define OMAP4_KBD_WAKEUPENABLE 0x20
30 #define OMAP4_KBD_PENDING 0x24
31 #define OMAP4_KBD_CTRL 0x28
32 #define OMAP4_KBD_DEBOUNCINGTIME 0x2C
33 #define OMAP4_KBD_LONGKEYTIME 0x30
34 #define OMAP4_KBD_TIMEOUT 0x34
35 #define OMAP4_KBD_STATEMACHINE 0x38
36 #define OMAP4_KBD_ROWINPUTS 0x3C
37 #define OMAP4_KBD_COLUMNOUTPUTS 0x40
38 #define OMAP4_KBD_FULLCODE31_0 0x44
39 #define OMAP4_KBD_FULLCODE63_32 0x48
40
41 /* OMAP4 bit definitions */
42 #define OMAP4_DEF_IRQENABLE_EVENTEN BIT(0)
43 #define OMAP4_DEF_IRQENABLE_LONGKEY BIT(1)
44 #define OMAP4_DEF_WUP_EVENT_ENA BIT(0)
45 #define OMAP4_DEF_WUP_LONG_KEY_ENA BIT(1)
46 #define OMAP4_DEF_CTRL_NOSOFTMODE BIT(1)
47 #define OMAP4_DEF_CTRL_PTV_SHIFT 2
48
49 /* OMAP4 values */
50 #define OMAP4_VAL_IRQDISABLE 0x0
51
52 /*
53 * Errata i689: If a key is released for a time shorter than debounce time,
54 * the keyboard will idle and never detect the key release. The workaround
55 * is to use at least a 12ms debounce time. See omap5432 TRM chapter
56 * "26.4.6.2 Keyboard Controller Timer" for more information.
57 */
58 #define OMAP4_KEYPAD_PTV_DIV_128 0x6
59 #define OMAP4_KEYPAD_DEBOUNCINGTIME_MS(dbms, ptv) \
60 ((((dbms) * 1000) / ((1 << ((ptv) + 1)) * (1000000 / 32768))) - 1)
61 #define OMAP4_VAL_DEBOUNCINGTIME_16MS \
62 OMAP4_KEYPAD_DEBOUNCINGTIME_MS(16, OMAP4_KEYPAD_PTV_DIV_128)
63 #define OMAP4_KEYPAD_AUTOIDLE_MS 50 /* Approximate measured time */
64 #define OMAP4_KEYPAD_IDLE_CHECK_MS (OMAP4_KEYPAD_AUTOIDLE_MS / 2)
65
66 enum {
67 KBD_REVISION_OMAP4 = 0,
68 KBD_REVISION_OMAP5,
69 };
70
71 struct omap4_keypad {
72 struct input_dev *input;
73
74 void __iomem *base;
75 unsigned int irq;
76 struct mutex lock; /* for key scan */
77
78 unsigned int rows;
79 unsigned int cols;
80 u32 reg_offset;
81 u32 irqreg_offset;
82 unsigned int row_shift;
83 bool no_autorepeat;
84 u64 keys;
85 unsigned short *keymap;
86 };
87
kbd_readl(struct omap4_keypad * keypad_data,u32 offset)88 static int kbd_readl(struct omap4_keypad *keypad_data, u32 offset)
89 {
90 return __raw_readl(keypad_data->base +
91 keypad_data->reg_offset + offset);
92 }
93
kbd_writel(struct omap4_keypad * keypad_data,u32 offset,u32 value)94 static void kbd_writel(struct omap4_keypad *keypad_data, u32 offset, u32 value)
95 {
96 __raw_writel(value,
97 keypad_data->base + keypad_data->reg_offset + offset);
98 }
99
kbd_read_irqreg(struct omap4_keypad * keypad_data,u32 offset)100 static int kbd_read_irqreg(struct omap4_keypad *keypad_data, u32 offset)
101 {
102 return __raw_readl(keypad_data->base +
103 keypad_data->irqreg_offset + offset);
104 }
105
kbd_write_irqreg(struct omap4_keypad * keypad_data,u32 offset,u32 value)106 static void kbd_write_irqreg(struct omap4_keypad *keypad_data,
107 u32 offset, u32 value)
108 {
109 __raw_writel(value,
110 keypad_data->base + keypad_data->irqreg_offset + offset);
111 }
112
omap4_keypad_report_keys(struct omap4_keypad * keypad_data,u64 keys,bool down)113 static int omap4_keypad_report_keys(struct omap4_keypad *keypad_data,
114 u64 keys, bool down)
115 {
116 struct input_dev *input_dev = keypad_data->input;
117 unsigned int col, row, code;
118 DECLARE_BITMAP(mask, 64);
119 unsigned long bit;
120 int events = 0;
121
122 bitmap_from_u64(mask, keys);
123
124 for_each_set_bit(bit, mask, keypad_data->rows * BITS_PER_BYTE) {
125 row = bit / BITS_PER_BYTE;
126 col = bit % BITS_PER_BYTE;
127 code = MATRIX_SCAN_CODE(row, col, keypad_data->row_shift);
128
129 input_event(input_dev, EV_MSC, MSC_SCAN, code);
130 input_report_key(input_dev, keypad_data->keymap[code], down);
131
132 events++;
133 }
134
135 if (events)
136 input_sync(input_dev);
137
138 return events;
139 }
140
omap4_keypad_scan_keys(struct omap4_keypad * keypad_data,u64 keys)141 static void omap4_keypad_scan_keys(struct omap4_keypad *keypad_data, u64 keys)
142 {
143 u64 changed;
144
145 mutex_lock(&keypad_data->lock);
146
147 changed = keys ^ keypad_data->keys;
148
149 /*
150 * Report key up events separately and first. This matters in case we
151 * lost key-up interrupt and just now catching up.
152 */
153 omap4_keypad_report_keys(keypad_data, changed & ~keys, false);
154
155 /* Report key down events */
156 omap4_keypad_report_keys(keypad_data, changed & keys, true);
157
158 keypad_data->keys = keys;
159
160 mutex_unlock(&keypad_data->lock);
161 }
162
163 /* Interrupt handlers */
omap4_keypad_irq_handler(int irq,void * dev_id)164 static irqreturn_t omap4_keypad_irq_handler(int irq, void *dev_id)
165 {
166 struct omap4_keypad *keypad_data = dev_id;
167
168 if (kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS))
169 return IRQ_WAKE_THREAD;
170
171 return IRQ_NONE;
172 }
173
omap4_keypad_irq_thread_fn(int irq,void * dev_id)174 static irqreturn_t omap4_keypad_irq_thread_fn(int irq, void *dev_id)
175 {
176 struct omap4_keypad *keypad_data = dev_id;
177 struct device *dev = keypad_data->input->dev.parent;
178 u32 low, high;
179 int error;
180 u64 keys;
181
182 error = pm_runtime_get_sync(dev);
183 if (error < 0) {
184 pm_runtime_put_noidle(dev);
185 return IRQ_NONE;
186 }
187
188 low = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE31_0);
189 high = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE63_32);
190 keys = low | (u64)high << 32;
191
192 omap4_keypad_scan_keys(keypad_data, keys);
193
194 /* clear pending interrupts */
195 kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
196 kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
197
198 pm_runtime_mark_last_busy(dev);
199 pm_runtime_put_autosuspend(dev);
200
201 return IRQ_HANDLED;
202 }
203
omap4_keypad_open(struct input_dev * input)204 static int omap4_keypad_open(struct input_dev *input)
205 {
206 struct omap4_keypad *keypad_data = input_get_drvdata(input);
207 struct device *dev = input->dev.parent;
208 int error;
209
210 error = pm_runtime_get_sync(dev);
211 if (error < 0) {
212 pm_runtime_put_noidle(dev);
213 return error;
214 }
215
216 disable_irq(keypad_data->irq);
217
218 kbd_writel(keypad_data, OMAP4_KBD_CTRL,
219 OMAP4_DEF_CTRL_NOSOFTMODE |
220 (OMAP4_KEYPAD_PTV_DIV_128 << OMAP4_DEF_CTRL_PTV_SHIFT));
221 kbd_writel(keypad_data, OMAP4_KBD_DEBOUNCINGTIME,
222 OMAP4_VAL_DEBOUNCINGTIME_16MS);
223 /* clear pending interrupts */
224 kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
225 kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
226 kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
227 OMAP4_DEF_IRQENABLE_EVENTEN);
228 kbd_writel(keypad_data, OMAP4_KBD_WAKEUPENABLE,
229 OMAP4_DEF_WUP_EVENT_ENA);
230
231 enable_irq(keypad_data->irq);
232
233 pm_runtime_mark_last_busy(dev);
234 pm_runtime_put_autosuspend(dev);
235
236 return 0;
237 }
238
omap4_keypad_stop(struct omap4_keypad * keypad_data)239 static void omap4_keypad_stop(struct omap4_keypad *keypad_data)
240 {
241 /* Disable interrupts and wake-up events */
242 kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
243 OMAP4_VAL_IRQDISABLE);
244 kbd_writel(keypad_data, OMAP4_KBD_WAKEUPENABLE, 0);
245
246 /* clear pending interrupts */
247 kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
248 kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
249 }
250
omap4_keypad_close(struct input_dev * input)251 static void omap4_keypad_close(struct input_dev *input)
252 {
253 struct omap4_keypad *keypad_data = input_get_drvdata(input);
254 struct device *dev = input->dev.parent;
255 int error;
256
257 error = pm_runtime_get_sync(dev);
258 if (error < 0)
259 pm_runtime_put_noidle(dev);
260
261 disable_irq(keypad_data->irq);
262 omap4_keypad_stop(keypad_data);
263 enable_irq(keypad_data->irq);
264
265 pm_runtime_mark_last_busy(dev);
266 pm_runtime_put_autosuspend(dev);
267 }
268
omap4_keypad_parse_dt(struct device * dev,struct omap4_keypad * keypad_data)269 static int omap4_keypad_parse_dt(struct device *dev,
270 struct omap4_keypad *keypad_data)
271 {
272 struct device_node *np = dev->of_node;
273 int err;
274
275 err = matrix_keypad_parse_properties(dev, &keypad_data->rows,
276 &keypad_data->cols);
277 if (err)
278 return err;
279
280 if (of_get_property(np, "linux,input-no-autorepeat", NULL))
281 keypad_data->no_autorepeat = true;
282
283 return 0;
284 }
285
omap4_keypad_check_revision(struct device * dev,struct omap4_keypad * keypad_data)286 static int omap4_keypad_check_revision(struct device *dev,
287 struct omap4_keypad *keypad_data)
288 {
289 unsigned int rev;
290
291 rev = __raw_readl(keypad_data->base + OMAP4_KBD_REVISION);
292 rev &= 0x03 << 30;
293 rev >>= 30;
294 switch (rev) {
295 case KBD_REVISION_OMAP4:
296 keypad_data->reg_offset = 0x00;
297 keypad_data->irqreg_offset = 0x00;
298 break;
299 case KBD_REVISION_OMAP5:
300 keypad_data->reg_offset = 0x10;
301 keypad_data->irqreg_offset = 0x0c;
302 break;
303 default:
304 dev_err(dev, "Keypad reports unsupported revision %d", rev);
305 return -EINVAL;
306 }
307
308 return 0;
309 }
310
311 /*
312 * Errata ID i689 "1.32 Keyboard Key Up Event Can Be Missed".
313 * Interrupt may not happen for key-up events. We must clear stuck
314 * key-up events after the keyboard hardware has auto-idled.
315 */
omap4_keypad_runtime_suspend(struct device * dev)316 static int __maybe_unused omap4_keypad_runtime_suspend(struct device *dev)
317 {
318 struct platform_device *pdev = to_platform_device(dev);
319 struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);
320 u32 active;
321
322 active = kbd_readl(keypad_data, OMAP4_KBD_STATEMACHINE);
323 if (active) {
324 pm_runtime_mark_last_busy(dev);
325 return -EBUSY;
326 }
327
328 omap4_keypad_scan_keys(keypad_data, 0);
329
330 return 0;
331 }
332
333 static const struct dev_pm_ops omap4_keypad_pm_ops = {
334 SET_RUNTIME_PM_OPS(omap4_keypad_runtime_suspend, NULL, NULL)
335 };
336
omap4_disable_pm(void * d)337 static void omap4_disable_pm(void *d)
338 {
339 pm_runtime_dont_use_autosuspend(d);
340 pm_runtime_disable(d);
341 }
342
omap4_keypad_probe(struct platform_device * pdev)343 static int omap4_keypad_probe(struct platform_device *pdev)
344 {
345 struct device *dev = &pdev->dev;
346 struct omap4_keypad *keypad_data;
347 struct input_dev *input_dev;
348 struct resource *res;
349 unsigned int max_keys;
350 int irq;
351 int error;
352
353 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
354 if (!res) {
355 dev_err(&pdev->dev, "no base address specified\n");
356 return -EINVAL;
357 }
358
359 irq = platform_get_irq(pdev, 0);
360 if (irq < 0)
361 return irq;
362
363 keypad_data = devm_kzalloc(dev, sizeof(*keypad_data), GFP_KERNEL);
364 if (!keypad_data) {
365 dev_err(dev, "keypad_data memory allocation failed\n");
366 return -ENOMEM;
367 }
368
369 keypad_data->irq = irq;
370 mutex_init(&keypad_data->lock);
371 platform_set_drvdata(pdev, keypad_data);
372
373 error = omap4_keypad_parse_dt(dev, keypad_data);
374 if (error)
375 return error;
376
377 keypad_data->base = devm_ioremap_resource(dev, res);
378 if (IS_ERR(keypad_data->base))
379 return PTR_ERR(keypad_data->base);
380
381 pm_runtime_use_autosuspend(dev);
382 pm_runtime_set_autosuspend_delay(dev, OMAP4_KEYPAD_IDLE_CHECK_MS);
383 pm_runtime_enable(dev);
384
385 error = devm_add_action_or_reset(dev, omap4_disable_pm, dev);
386 if (error) {
387 dev_err(dev, "unable to register cleanup action\n");
388 return error;
389 }
390
391 /*
392 * Enable clocks for the keypad module so that we can read
393 * revision register.
394 */
395 error = pm_runtime_get_sync(dev);
396 if (error < 0) {
397 dev_err(dev, "pm_runtime_get_sync() failed\n");
398 pm_runtime_put_noidle(dev);
399 return error;
400 }
401
402 error = omap4_keypad_check_revision(dev, keypad_data);
403 if (!error) {
404 /* Ensure device does not raise interrupts */
405 omap4_keypad_stop(keypad_data);
406 }
407
408 pm_runtime_mark_last_busy(dev);
409 pm_runtime_put_autosuspend(dev);
410 if (error)
411 return error;
412
413 /* input device allocation */
414 keypad_data->input = input_dev = devm_input_allocate_device(dev);
415 if (!input_dev)
416 return -ENOMEM;
417
418 input_dev->name = pdev->name;
419 input_dev->id.bustype = BUS_HOST;
420 input_dev->id.vendor = 0x0001;
421 input_dev->id.product = 0x0001;
422 input_dev->id.version = 0x0001;
423
424 input_dev->open = omap4_keypad_open;
425 input_dev->close = omap4_keypad_close;
426
427 input_set_capability(input_dev, EV_MSC, MSC_SCAN);
428 if (!keypad_data->no_autorepeat)
429 __set_bit(EV_REP, input_dev->evbit);
430
431 input_set_drvdata(input_dev, keypad_data);
432
433 keypad_data->row_shift = get_count_order(keypad_data->cols);
434 max_keys = keypad_data->rows << keypad_data->row_shift;
435 keypad_data->keymap = devm_kcalloc(dev,
436 max_keys,
437 sizeof(keypad_data->keymap[0]),
438 GFP_KERNEL);
439 if (!keypad_data->keymap) {
440 dev_err(dev, "Not enough memory for keymap\n");
441 return -ENOMEM;
442 }
443
444 error = matrix_keypad_build_keymap(NULL, NULL,
445 keypad_data->rows, keypad_data->cols,
446 keypad_data->keymap, input_dev);
447 if (error) {
448 dev_err(dev, "failed to build keymap\n");
449 return error;
450 }
451
452 error = devm_request_threaded_irq(dev, keypad_data->irq,
453 omap4_keypad_irq_handler,
454 omap4_keypad_irq_thread_fn,
455 IRQF_ONESHOT,
456 "omap4-keypad", keypad_data);
457 if (error) {
458 dev_err(dev, "failed to register interrupt\n");
459 return error;
460 }
461
462 error = input_register_device(keypad_data->input);
463 if (error) {
464 dev_err(dev, "failed to register input device\n");
465 return error;
466 }
467
468 device_init_wakeup(dev, true);
469 error = dev_pm_set_wake_irq(dev, keypad_data->irq);
470 if (error)
471 dev_warn(dev, "failed to set up wakeup irq: %d\n", error);
472
473 return 0;
474 }
475
omap4_keypad_remove(struct platform_device * pdev)476 static int omap4_keypad_remove(struct platform_device *pdev)
477 {
478 dev_pm_clear_wake_irq(&pdev->dev);
479
480 return 0;
481 }
482
483 static const struct of_device_id omap_keypad_dt_match[] = {
484 { .compatible = "ti,omap4-keypad" },
485 {},
486 };
487 MODULE_DEVICE_TABLE(of, omap_keypad_dt_match);
488
489 static struct platform_driver omap4_keypad_driver = {
490 .probe = omap4_keypad_probe,
491 .remove = omap4_keypad_remove,
492 .driver = {
493 .name = "omap4-keypad",
494 .of_match_table = omap_keypad_dt_match,
495 .pm = &omap4_keypad_pm_ops,
496 },
497 };
498 module_platform_driver(omap4_keypad_driver);
499
500 MODULE_AUTHOR("Texas Instruments");
501 MODULE_DESCRIPTION("OMAP4 Keypad Driver");
502 MODULE_LICENSE("GPL");
503 MODULE_ALIAS("platform:omap4-keypad");
504