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_resume_and_get(dev);
183 if (error)
184 return IRQ_NONE;
185
186 low = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE31_0);
187 high = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE63_32);
188 keys = low | (u64)high << 32;
189
190 omap4_keypad_scan_keys(keypad_data, keys);
191
192 /* clear pending interrupts */
193 kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
194 kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
195
196 pm_runtime_mark_last_busy(dev);
197 pm_runtime_put_autosuspend(dev);
198
199 return IRQ_HANDLED;
200 }
201
omap4_keypad_open(struct input_dev * input)202 static int omap4_keypad_open(struct input_dev *input)
203 {
204 struct omap4_keypad *keypad_data = input_get_drvdata(input);
205 struct device *dev = input->dev.parent;
206 int error;
207
208 error = pm_runtime_resume_and_get(dev);
209 if (error)
210 return error;
211
212 disable_irq(keypad_data->irq);
213
214 kbd_writel(keypad_data, OMAP4_KBD_CTRL,
215 OMAP4_DEF_CTRL_NOSOFTMODE |
216 (OMAP4_KEYPAD_PTV_DIV_128 << OMAP4_DEF_CTRL_PTV_SHIFT));
217 kbd_writel(keypad_data, OMAP4_KBD_DEBOUNCINGTIME,
218 OMAP4_VAL_DEBOUNCINGTIME_16MS);
219 /* clear pending interrupts */
220 kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
221 kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
222 kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
223 OMAP4_DEF_IRQENABLE_EVENTEN);
224 kbd_writel(keypad_data, OMAP4_KBD_WAKEUPENABLE,
225 OMAP4_DEF_WUP_EVENT_ENA);
226
227 enable_irq(keypad_data->irq);
228
229 pm_runtime_mark_last_busy(dev);
230 pm_runtime_put_autosuspend(dev);
231
232 return 0;
233 }
234
omap4_keypad_stop(struct omap4_keypad * keypad_data)235 static void omap4_keypad_stop(struct omap4_keypad *keypad_data)
236 {
237 /* Disable interrupts and wake-up events */
238 kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
239 OMAP4_VAL_IRQDISABLE);
240 kbd_writel(keypad_data, OMAP4_KBD_WAKEUPENABLE, 0);
241
242 /* clear pending interrupts */
243 kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
244 kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
245 }
246
omap4_keypad_close(struct input_dev * input)247 static void omap4_keypad_close(struct input_dev *input)
248 {
249 struct omap4_keypad *keypad_data = input_get_drvdata(input);
250 struct device *dev = input->dev.parent;
251 int error;
252
253 error = pm_runtime_resume_and_get(dev);
254 if (error)
255 dev_err(dev, "%s: pm_runtime_resume_and_get() failed: %d\n",
256 __func__, error);
257
258 disable_irq(keypad_data->irq);
259 omap4_keypad_stop(keypad_data);
260 enable_irq(keypad_data->irq);
261
262 pm_runtime_mark_last_busy(dev);
263 pm_runtime_put_autosuspend(dev);
264 }
265
omap4_keypad_parse_dt(struct device * dev,struct omap4_keypad * keypad_data)266 static int omap4_keypad_parse_dt(struct device *dev,
267 struct omap4_keypad *keypad_data)
268 {
269 struct device_node *np = dev->of_node;
270 int err;
271
272 err = matrix_keypad_parse_properties(dev, &keypad_data->rows,
273 &keypad_data->cols);
274 if (err)
275 return err;
276
277 if (of_get_property(np, "linux,input-no-autorepeat", NULL))
278 keypad_data->no_autorepeat = true;
279
280 return 0;
281 }
282
omap4_keypad_check_revision(struct device * dev,struct omap4_keypad * keypad_data)283 static int omap4_keypad_check_revision(struct device *dev,
284 struct omap4_keypad *keypad_data)
285 {
286 unsigned int rev;
287
288 rev = __raw_readl(keypad_data->base + OMAP4_KBD_REVISION);
289 rev &= 0x03 << 30;
290 rev >>= 30;
291 switch (rev) {
292 case KBD_REVISION_OMAP4:
293 keypad_data->reg_offset = 0x00;
294 keypad_data->irqreg_offset = 0x00;
295 break;
296 case KBD_REVISION_OMAP5:
297 keypad_data->reg_offset = 0x10;
298 keypad_data->irqreg_offset = 0x0c;
299 break;
300 default:
301 dev_err(dev, "Keypad reports unsupported revision %d", rev);
302 return -EINVAL;
303 }
304
305 return 0;
306 }
307
308 /*
309 * Errata ID i689 "1.32 Keyboard Key Up Event Can Be Missed".
310 * Interrupt may not happen for key-up events. We must clear stuck
311 * key-up events after the keyboard hardware has auto-idled.
312 */
omap4_keypad_runtime_suspend(struct device * dev)313 static int __maybe_unused omap4_keypad_runtime_suspend(struct device *dev)
314 {
315 struct platform_device *pdev = to_platform_device(dev);
316 struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);
317 u32 active;
318
319 active = kbd_readl(keypad_data, OMAP4_KBD_STATEMACHINE);
320 if (active) {
321 pm_runtime_mark_last_busy(dev);
322 return -EBUSY;
323 }
324
325 omap4_keypad_scan_keys(keypad_data, 0);
326
327 return 0;
328 }
329
330 static const struct dev_pm_ops omap4_keypad_pm_ops = {
331 SET_RUNTIME_PM_OPS(omap4_keypad_runtime_suspend, NULL, NULL)
332 };
333
omap4_disable_pm(void * d)334 static void omap4_disable_pm(void *d)
335 {
336 pm_runtime_dont_use_autosuspend(d);
337 pm_runtime_disable(d);
338 }
339
omap4_keypad_probe(struct platform_device * pdev)340 static int omap4_keypad_probe(struct platform_device *pdev)
341 {
342 struct device *dev = &pdev->dev;
343 struct omap4_keypad *keypad_data;
344 struct input_dev *input_dev;
345 struct resource *res;
346 unsigned int max_keys;
347 int irq;
348 int error;
349
350 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
351 if (!res) {
352 dev_err(&pdev->dev, "no base address specified\n");
353 return -EINVAL;
354 }
355
356 irq = platform_get_irq(pdev, 0);
357 if (irq < 0)
358 return irq;
359
360 keypad_data = devm_kzalloc(dev, sizeof(*keypad_data), GFP_KERNEL);
361 if (!keypad_data) {
362 dev_err(dev, "keypad_data memory allocation failed\n");
363 return -ENOMEM;
364 }
365
366 keypad_data->irq = irq;
367 mutex_init(&keypad_data->lock);
368 platform_set_drvdata(pdev, keypad_data);
369
370 error = omap4_keypad_parse_dt(dev, keypad_data);
371 if (error)
372 return error;
373
374 keypad_data->base = devm_ioremap_resource(dev, res);
375 if (IS_ERR(keypad_data->base))
376 return PTR_ERR(keypad_data->base);
377
378 pm_runtime_use_autosuspend(dev);
379 pm_runtime_set_autosuspend_delay(dev, OMAP4_KEYPAD_IDLE_CHECK_MS);
380 pm_runtime_enable(dev);
381
382 error = devm_add_action_or_reset(dev, omap4_disable_pm, dev);
383 if (error) {
384 dev_err(dev, "unable to register cleanup action\n");
385 return error;
386 }
387
388 /*
389 * Enable clocks for the keypad module so that we can read
390 * revision register.
391 */
392 error = pm_runtime_resume_and_get(dev);
393 if (error) {
394 dev_err(dev, "pm_runtime_resume_and_get() failed\n");
395 return error;
396 }
397
398 error = omap4_keypad_check_revision(dev, keypad_data);
399 if (!error) {
400 /* Ensure device does not raise interrupts */
401 omap4_keypad_stop(keypad_data);
402 }
403
404 pm_runtime_mark_last_busy(dev);
405 pm_runtime_put_autosuspend(dev);
406 if (error)
407 return error;
408
409 /* input device allocation */
410 keypad_data->input = input_dev = devm_input_allocate_device(dev);
411 if (!input_dev)
412 return -ENOMEM;
413
414 input_dev->name = pdev->name;
415 input_dev->id.bustype = BUS_HOST;
416 input_dev->id.vendor = 0x0001;
417 input_dev->id.product = 0x0001;
418 input_dev->id.version = 0x0001;
419
420 input_dev->open = omap4_keypad_open;
421 input_dev->close = omap4_keypad_close;
422
423 input_set_capability(input_dev, EV_MSC, MSC_SCAN);
424 if (!keypad_data->no_autorepeat)
425 __set_bit(EV_REP, input_dev->evbit);
426
427 input_set_drvdata(input_dev, keypad_data);
428
429 keypad_data->row_shift = get_count_order(keypad_data->cols);
430 max_keys = keypad_data->rows << keypad_data->row_shift;
431 keypad_data->keymap = devm_kcalloc(dev,
432 max_keys,
433 sizeof(keypad_data->keymap[0]),
434 GFP_KERNEL);
435 if (!keypad_data->keymap) {
436 dev_err(dev, "Not enough memory for keymap\n");
437 return -ENOMEM;
438 }
439
440 error = matrix_keypad_build_keymap(NULL, NULL,
441 keypad_data->rows, keypad_data->cols,
442 keypad_data->keymap, input_dev);
443 if (error) {
444 dev_err(dev, "failed to build keymap\n");
445 return error;
446 }
447
448 error = devm_request_threaded_irq(dev, keypad_data->irq,
449 omap4_keypad_irq_handler,
450 omap4_keypad_irq_thread_fn,
451 IRQF_ONESHOT,
452 "omap4-keypad", keypad_data);
453 if (error) {
454 dev_err(dev, "failed to register interrupt\n");
455 return error;
456 }
457
458 error = input_register_device(keypad_data->input);
459 if (error) {
460 dev_err(dev, "failed to register input device\n");
461 return error;
462 }
463
464 device_init_wakeup(dev, true);
465 error = dev_pm_set_wake_irq(dev, keypad_data->irq);
466 if (error)
467 dev_warn(dev, "failed to set up wakeup irq: %d\n", error);
468
469 return 0;
470 }
471
omap4_keypad_remove(struct platform_device * pdev)472 static int omap4_keypad_remove(struct platform_device *pdev)
473 {
474 dev_pm_clear_wake_irq(&pdev->dev);
475
476 return 0;
477 }
478
479 static const struct of_device_id omap_keypad_dt_match[] = {
480 { .compatible = "ti,omap4-keypad" },
481 {},
482 };
483 MODULE_DEVICE_TABLE(of, omap_keypad_dt_match);
484
485 static struct platform_driver omap4_keypad_driver = {
486 .probe = omap4_keypad_probe,
487 .remove = omap4_keypad_remove,
488 .driver = {
489 .name = "omap4-keypad",
490 .of_match_table = omap_keypad_dt_match,
491 .pm = &omap4_keypad_pm_ops,
492 },
493 };
494 module_platform_driver(omap4_keypad_driver);
495
496 MODULE_AUTHOR("Texas Instruments");
497 MODULE_DESCRIPTION("OMAP4 Keypad Driver");
498 MODULE_LICENSE("GPL");
499 MODULE_ALIAS("platform:omap4-keypad");
500