1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) ST-Ericsson SA 2010
4 *
5 * Author: Jayeeta Banerjee <jayeeta.banerjee@stericsson.com>
6 * Author: Sundar Iyer <sundar.iyer@stericsson.com>
7 *
8 * TC35893 MFD Keypad Controller driver
9 */
10
11 #include <linux/module.h>
12 #include <linux/interrupt.h>
13 #include <linux/input.h>
14 #include <linux/platform_device.h>
15 #include <linux/input/matrix_keypad.h>
16 #include <linux/i2c.h>
17 #include <linux/slab.h>
18 #include <linux/mfd/tc3589x.h>
19 #include <linux/device.h>
20
21 /* Maximum supported keypad matrix row/columns size */
22 #define TC3589x_MAX_KPROW 8
23 #define TC3589x_MAX_KPCOL 12
24
25 /* keypad related Constants */
26 #define TC3589x_MAX_DEBOUNCE_SETTLE 0xFF
27 #define DEDICATED_KEY_VAL 0xFF
28
29 /* Pull up/down masks */
30 #define TC3589x_NO_PULL_MASK 0x0
31 #define TC3589x_PULL_DOWN_MASK 0x1
32 #define TC3589x_PULL_UP_MASK 0x2
33 #define TC3589x_PULLUP_ALL_MASK 0xAA
34 #define TC3589x_IO_PULL_VAL(index, mask) ((mask)<<((index)%4)*2)
35
36 /* Bit masks for IOCFG register */
37 #define IOCFG_BALLCFG 0x01
38 #define IOCFG_IG 0x08
39
40 #define KP_EVCODE_COL_MASK 0x0F
41 #define KP_EVCODE_ROW_MASK 0x70
42 #define KP_RELEASE_EVT_MASK 0x80
43
44 #define KP_ROW_SHIFT 4
45
46 #define KP_NO_VALID_KEY_MASK 0x7F
47
48 /* bit masks for RESTCTRL register */
49 #define TC3589x_KBDRST 0x2
50 #define TC3589x_IRQRST 0x10
51 #define TC3589x_RESET_ALL 0x1B
52
53 /* KBDMFS register bit mask */
54 #define TC3589x_KBDMFS_EN 0x1
55
56 /* CLKEN register bitmask */
57 #define KPD_CLK_EN 0x1
58
59 /* RSTINTCLR register bit mask */
60 #define IRQ_CLEAR 0x1
61
62 /* bit masks for keyboard interrupts*/
63 #define TC3589x_EVT_LOSS_INT 0x8
64 #define TC3589x_EVT_INT 0x4
65 #define TC3589x_KBD_LOSS_INT 0x2
66 #define TC3589x_KBD_INT 0x1
67
68 /* bit masks for keyboard interrupt clear*/
69 #define TC3589x_EVT_INT_CLR 0x2
70 #define TC3589x_KBD_INT_CLR 0x1
71
72 /**
73 * struct tc3589x_keypad_platform_data - platform specific keypad data
74 * @keymap_data: matrix scan code table for keycodes
75 * @krow: mask for available rows, value is 0xFF
76 * @kcol: mask for available columns, value is 0xFF
77 * @debounce_period: platform specific debounce time
78 * @settle_time: platform specific settle down time
79 * @irqtype: type of interrupt, falling or rising edge
80 * @enable_wakeup: specifies if keypad event can wake up system from sleep
81 * @no_autorepeat: flag for auto repetition
82 */
83 struct tc3589x_keypad_platform_data {
84 const struct matrix_keymap_data *keymap_data;
85 u8 krow;
86 u8 kcol;
87 u8 debounce_period;
88 u8 settle_time;
89 unsigned long irqtype;
90 bool enable_wakeup;
91 bool no_autorepeat;
92 };
93
94 /**
95 * struct tc_keypad - data structure used by keypad driver
96 * @tc3589x: pointer to tc35893
97 * @input: pointer to input device object
98 * @board: keypad platform device
99 * @krow: number of rows
100 * @kcol: number of columns
101 * @keymap: matrix scan code table for keycodes
102 * @keypad_stopped: holds keypad status
103 */
104 struct tc_keypad {
105 struct tc3589x *tc3589x;
106 struct input_dev *input;
107 const struct tc3589x_keypad_platform_data *board;
108 unsigned int krow;
109 unsigned int kcol;
110 unsigned short *keymap;
111 bool keypad_stopped;
112 };
113
tc3589x_keypad_init_key_hardware(struct tc_keypad * keypad)114 static int tc3589x_keypad_init_key_hardware(struct tc_keypad *keypad)
115 {
116 int ret;
117 struct tc3589x *tc3589x = keypad->tc3589x;
118 const struct tc3589x_keypad_platform_data *board = keypad->board;
119
120 /* validate platform configuration */
121 if (board->kcol > TC3589x_MAX_KPCOL || board->krow > TC3589x_MAX_KPROW)
122 return -EINVAL;
123
124 /* configure KBDSIZE 4 LSbits for cols and 4 MSbits for rows */
125 ret = tc3589x_reg_write(tc3589x, TC3589x_KBDSIZE,
126 (board->krow << KP_ROW_SHIFT) | board->kcol);
127 if (ret < 0)
128 return ret;
129
130 /* configure dedicated key config, no dedicated key selected */
131 ret = tc3589x_reg_write(tc3589x, TC3589x_KBCFG_LSB, DEDICATED_KEY_VAL);
132 if (ret < 0)
133 return ret;
134
135 ret = tc3589x_reg_write(tc3589x, TC3589x_KBCFG_MSB, DEDICATED_KEY_VAL);
136 if (ret < 0)
137 return ret;
138
139 /* Configure settle time */
140 ret = tc3589x_reg_write(tc3589x, TC3589x_KBDSETTLE_REG,
141 board->settle_time);
142 if (ret < 0)
143 return ret;
144
145 /* Configure debounce time */
146 ret = tc3589x_reg_write(tc3589x, TC3589x_KBDBOUNCE,
147 board->debounce_period);
148 if (ret < 0)
149 return ret;
150
151 /* Start of initialise keypad GPIOs */
152 ret = tc3589x_set_bits(tc3589x, TC3589x_IOCFG, 0x0, IOCFG_IG);
153 if (ret < 0)
154 return ret;
155
156 /* Configure pull-up resistors for all row GPIOs */
157 ret = tc3589x_reg_write(tc3589x, TC3589x_IOPULLCFG0_LSB,
158 TC3589x_PULLUP_ALL_MASK);
159 if (ret < 0)
160 return ret;
161
162 ret = tc3589x_reg_write(tc3589x, TC3589x_IOPULLCFG0_MSB,
163 TC3589x_PULLUP_ALL_MASK);
164 if (ret < 0)
165 return ret;
166
167 /* Configure pull-up resistors for all column GPIOs */
168 ret = tc3589x_reg_write(tc3589x, TC3589x_IOPULLCFG1_LSB,
169 TC3589x_PULLUP_ALL_MASK);
170 if (ret < 0)
171 return ret;
172
173 ret = tc3589x_reg_write(tc3589x, TC3589x_IOPULLCFG1_MSB,
174 TC3589x_PULLUP_ALL_MASK);
175 if (ret < 0)
176 return ret;
177
178 ret = tc3589x_reg_write(tc3589x, TC3589x_IOPULLCFG2_LSB,
179 TC3589x_PULLUP_ALL_MASK);
180
181 return ret;
182 }
183
184 #define TC35893_DATA_REGS 4
185 #define TC35893_KEYCODE_FIFO_EMPTY 0x7f
186 #define TC35893_KEYCODE_FIFO_CLEAR 0xff
187 #define TC35893_KEYPAD_ROW_SHIFT 0x3
188
tc3589x_keypad_irq(int irq,void * dev)189 static irqreturn_t tc3589x_keypad_irq(int irq, void *dev)
190 {
191 struct tc_keypad *keypad = dev;
192 struct tc3589x *tc3589x = keypad->tc3589x;
193 u8 i, row_index, col_index, kbd_code, up;
194 u8 code;
195
196 for (i = 0; i < TC35893_DATA_REGS * 2; i++) {
197 kbd_code = tc3589x_reg_read(tc3589x, TC3589x_EVTCODE_FIFO);
198
199 /* loop till fifo is empty and no more keys are pressed */
200 if (kbd_code == TC35893_KEYCODE_FIFO_EMPTY ||
201 kbd_code == TC35893_KEYCODE_FIFO_CLEAR)
202 continue;
203
204 /* valid key is found */
205 col_index = kbd_code & KP_EVCODE_COL_MASK;
206 row_index = (kbd_code & KP_EVCODE_ROW_MASK) >> KP_ROW_SHIFT;
207 code = MATRIX_SCAN_CODE(row_index, col_index,
208 TC35893_KEYPAD_ROW_SHIFT);
209 up = kbd_code & KP_RELEASE_EVT_MASK;
210
211 input_event(keypad->input, EV_MSC, MSC_SCAN, code);
212 input_report_key(keypad->input, keypad->keymap[code], !up);
213 input_sync(keypad->input);
214 }
215
216 /* clear IRQ */
217 tc3589x_set_bits(tc3589x, TC3589x_KBDIC,
218 0x0, TC3589x_EVT_INT_CLR | TC3589x_KBD_INT_CLR);
219 /* enable IRQ */
220 tc3589x_set_bits(tc3589x, TC3589x_KBDMSK,
221 0x0, TC3589x_EVT_LOSS_INT | TC3589x_EVT_INT);
222
223 return IRQ_HANDLED;
224 }
225
tc3589x_keypad_enable(struct tc_keypad * keypad)226 static int tc3589x_keypad_enable(struct tc_keypad *keypad)
227 {
228 struct tc3589x *tc3589x = keypad->tc3589x;
229 int ret;
230
231 /* pull the keypad module out of reset */
232 ret = tc3589x_set_bits(tc3589x, TC3589x_RSTCTRL, TC3589x_KBDRST, 0x0);
233 if (ret < 0)
234 return ret;
235
236 /* configure KBDMFS */
237 ret = tc3589x_set_bits(tc3589x, TC3589x_KBDMFS, 0x0, TC3589x_KBDMFS_EN);
238 if (ret < 0)
239 return ret;
240
241 /* enable the keypad clock */
242 ret = tc3589x_set_bits(tc3589x, TC3589x_CLKEN, 0x0, KPD_CLK_EN);
243 if (ret < 0)
244 return ret;
245
246 /* clear pending IRQs */
247 ret = tc3589x_set_bits(tc3589x, TC3589x_RSTINTCLR, 0x0, 0x1);
248 if (ret < 0)
249 return ret;
250
251 /* enable the IRQs */
252 ret = tc3589x_set_bits(tc3589x, TC3589x_KBDMSK, 0x0,
253 TC3589x_EVT_LOSS_INT | TC3589x_EVT_INT);
254 if (ret < 0)
255 return ret;
256
257 keypad->keypad_stopped = false;
258
259 return ret;
260 }
261
tc3589x_keypad_disable(struct tc_keypad * keypad)262 static int tc3589x_keypad_disable(struct tc_keypad *keypad)
263 {
264 struct tc3589x *tc3589x = keypad->tc3589x;
265 int ret;
266
267 /* clear IRQ */
268 ret = tc3589x_set_bits(tc3589x, TC3589x_KBDIC,
269 0x0, TC3589x_EVT_INT_CLR | TC3589x_KBD_INT_CLR);
270 if (ret < 0)
271 return ret;
272
273 /* disable all interrupts */
274 ret = tc3589x_set_bits(tc3589x, TC3589x_KBDMSK,
275 ~(TC3589x_EVT_LOSS_INT | TC3589x_EVT_INT), 0x0);
276 if (ret < 0)
277 return ret;
278
279 /* disable the keypad module */
280 ret = tc3589x_set_bits(tc3589x, TC3589x_CLKEN, 0x1, 0x0);
281 if (ret < 0)
282 return ret;
283
284 /* put the keypad module into reset */
285 ret = tc3589x_set_bits(tc3589x, TC3589x_RSTCTRL, TC3589x_KBDRST, 0x1);
286
287 keypad->keypad_stopped = true;
288
289 return ret;
290 }
291
tc3589x_keypad_open(struct input_dev * input)292 static int tc3589x_keypad_open(struct input_dev *input)
293 {
294 int error;
295 struct tc_keypad *keypad = input_get_drvdata(input);
296
297 /* enable the keypad module */
298 error = tc3589x_keypad_enable(keypad);
299 if (error < 0) {
300 dev_err(&input->dev, "failed to enable keypad module\n");
301 return error;
302 }
303
304 error = tc3589x_keypad_init_key_hardware(keypad);
305 if (error < 0) {
306 dev_err(&input->dev, "failed to configure keypad module\n");
307 return error;
308 }
309
310 return 0;
311 }
312
tc3589x_keypad_close(struct input_dev * input)313 static void tc3589x_keypad_close(struct input_dev *input)
314 {
315 struct tc_keypad *keypad = input_get_drvdata(input);
316
317 /* disable the keypad module */
318 tc3589x_keypad_disable(keypad);
319 }
320
321 static const struct tc3589x_keypad_platform_data *
tc3589x_keypad_of_probe(struct device * dev)322 tc3589x_keypad_of_probe(struct device *dev)
323 {
324 struct device_node *np = dev->of_node;
325 struct tc3589x_keypad_platform_data *plat;
326 u32 cols, rows;
327 u32 debounce_ms;
328
329 if (!np)
330 return ERR_PTR(-ENODEV);
331
332 plat = devm_kzalloc(dev, sizeof(*plat), GFP_KERNEL);
333 if (!plat)
334 return ERR_PTR(-ENOMEM);
335
336 of_property_read_u32(np, "keypad,num-columns", &cols);
337 of_property_read_u32(np, "keypad,num-rows", &rows);
338 plat->kcol = (u8) cols;
339 plat->krow = (u8) rows;
340 if (!plat->krow || !plat->kcol ||
341 plat->krow > TC_KPD_ROWS || plat->kcol > TC_KPD_COLUMNS) {
342 dev_err(dev,
343 "keypad columns/rows not properly specified (%ux%u)\n",
344 plat->kcol, plat->krow);
345 return ERR_PTR(-EINVAL);
346 }
347
348 if (!of_property_present(np, "linux,keymap")) {
349 dev_err(dev, "property linux,keymap not found\n");
350 return ERR_PTR(-ENOENT);
351 }
352
353 plat->no_autorepeat = of_property_read_bool(np, "linux,no-autorepeat");
354
355 plat->enable_wakeup = of_property_read_bool(np, "wakeup-source") ||
356 /* legacy name */
357 of_property_read_bool(np, "linux,wakeup");
358
359 /* The custom delay format is ms/16 */
360 of_property_read_u32(np, "debounce-delay-ms", &debounce_ms);
361 if (debounce_ms)
362 plat->debounce_period = debounce_ms * 16;
363 else
364 plat->debounce_period = TC_KPD_DEBOUNCE_PERIOD;
365
366 plat->settle_time = TC_KPD_SETTLE_TIME;
367 /* FIXME: should be property of the IRQ resource? */
368 plat->irqtype = IRQF_TRIGGER_FALLING;
369
370 return plat;
371 }
372
tc3589x_keypad_probe(struct platform_device * pdev)373 static int tc3589x_keypad_probe(struct platform_device *pdev)
374 {
375 struct tc3589x *tc3589x = dev_get_drvdata(pdev->dev.parent);
376 struct tc_keypad *keypad;
377 struct input_dev *input;
378 const struct tc3589x_keypad_platform_data *plat;
379 int error, irq;
380
381 plat = tc3589x_keypad_of_probe(&pdev->dev);
382 if (IS_ERR(plat)) {
383 dev_err(&pdev->dev, "invalid keypad platform data\n");
384 return PTR_ERR(plat);
385 }
386
387 irq = platform_get_irq(pdev, 0);
388 if (irq < 0)
389 return irq;
390
391 keypad = devm_kzalloc(&pdev->dev, sizeof(struct tc_keypad),
392 GFP_KERNEL);
393 if (!keypad)
394 return -ENOMEM;
395
396 input = devm_input_allocate_device(&pdev->dev);
397 if (!input) {
398 dev_err(&pdev->dev, "failed to allocate input device\n");
399 return -ENOMEM;
400 }
401
402 keypad->board = plat;
403 keypad->input = input;
404 keypad->tc3589x = tc3589x;
405
406 input->id.bustype = BUS_I2C;
407 input->name = pdev->name;
408 input->dev.parent = &pdev->dev;
409
410 input->open = tc3589x_keypad_open;
411 input->close = tc3589x_keypad_close;
412
413 error = matrix_keypad_build_keymap(plat->keymap_data, NULL,
414 TC3589x_MAX_KPROW, TC3589x_MAX_KPCOL,
415 NULL, input);
416 if (error) {
417 dev_err(&pdev->dev, "Failed to build keymap\n");
418 return error;
419 }
420
421 keypad->keymap = input->keycode;
422
423 input_set_capability(input, EV_MSC, MSC_SCAN);
424 if (!plat->no_autorepeat)
425 __set_bit(EV_REP, input->evbit);
426
427 input_set_drvdata(input, keypad);
428
429 tc3589x_keypad_disable(keypad);
430
431 error = devm_request_threaded_irq(&pdev->dev, irq,
432 NULL, tc3589x_keypad_irq,
433 plat->irqtype | IRQF_ONESHOT,
434 "tc3589x-keypad", keypad);
435 if (error) {
436 dev_err(&pdev->dev,
437 "Could not allocate irq %d,error %d\n",
438 irq, error);
439 return error;
440 }
441
442 error = input_register_device(input);
443 if (error) {
444 dev_err(&pdev->dev, "Could not register input device\n");
445 return error;
446 }
447
448 /* let platform decide if keypad is a wakeup source or not */
449 device_init_wakeup(&pdev->dev, plat->enable_wakeup);
450 device_set_wakeup_capable(&pdev->dev, plat->enable_wakeup);
451
452 platform_set_drvdata(pdev, keypad);
453
454 return 0;
455 }
456
tc3589x_keypad_suspend(struct device * dev)457 static int tc3589x_keypad_suspend(struct device *dev)
458 {
459 struct platform_device *pdev = to_platform_device(dev);
460 struct tc_keypad *keypad = platform_get_drvdata(pdev);
461 int irq = platform_get_irq(pdev, 0);
462
463 /* keypad is already off; we do nothing */
464 if (keypad->keypad_stopped)
465 return 0;
466
467 /* if device is not a wakeup source, disable it for powersave */
468 if (!device_may_wakeup(&pdev->dev))
469 tc3589x_keypad_disable(keypad);
470 else
471 enable_irq_wake(irq);
472
473 return 0;
474 }
475
tc3589x_keypad_resume(struct device * dev)476 static int tc3589x_keypad_resume(struct device *dev)
477 {
478 struct platform_device *pdev = to_platform_device(dev);
479 struct tc_keypad *keypad = platform_get_drvdata(pdev);
480 int irq = platform_get_irq(pdev, 0);
481
482 if (!keypad->keypad_stopped)
483 return 0;
484
485 /* enable the device to resume normal operations */
486 if (!device_may_wakeup(&pdev->dev))
487 tc3589x_keypad_enable(keypad);
488 else
489 disable_irq_wake(irq);
490
491 return 0;
492 }
493
494 static DEFINE_SIMPLE_DEV_PM_OPS(tc3589x_keypad_dev_pm_ops,
495 tc3589x_keypad_suspend, tc3589x_keypad_resume);
496
497 static struct platform_driver tc3589x_keypad_driver = {
498 .driver = {
499 .name = "tc3589x-keypad",
500 .pm = pm_sleep_ptr(&tc3589x_keypad_dev_pm_ops),
501 },
502 .probe = tc3589x_keypad_probe,
503 };
504 module_platform_driver(tc3589x_keypad_driver);
505
506 MODULE_LICENSE("GPL v2");
507 MODULE_AUTHOR("Jayeeta Banerjee/Sundar Iyer");
508 MODULE_DESCRIPTION("TC35893 Keypad Driver");
509 MODULE_ALIAS("platform:tc3589x-keypad");
510