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