1/*
2 * Copyright (C) ST-Ericsson SA 2010
3 *
4 * Author: Jayeeta Banerjee <jayeeta.banerjee@stericsson.com>
5 * Author: Sundar Iyer <sundar.iyer@stericsson.com>
6 *
7 * License Terms: GNU General Public License, version 2
8 *
9 * TC35893 MFD Keypad Controller driver
10 */
11
12#include <linux/module.h>
13#include <linux/interrupt.h>
14#include <linux/input.h>
15#include <linux/platform_device.h>
16#include <linux/input/matrix_keypad.h>
17#include <linux/i2c.h>
18#include <linux/slab.h>
19#include <linux/mfd/tc3589x.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 tc35893_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 */
83struct 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 */
104struct 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
114static 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
189static 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
226static 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
262static 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
292static 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
313static 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
321static const struct tc3589x_keypad_platform_data *
322tc3589x_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	int proplen;
329
330	if (!np)
331		return ERR_PTR(-ENODEV);
332
333	plat = devm_kzalloc(dev, sizeof(*plat), GFP_KERNEL);
334	if (!plat)
335		return ERR_PTR(-ENOMEM);
336
337	of_property_read_u32(np, "keypad,num-columns", &cols);
338	of_property_read_u32(np, "keypad,num-rows", &rows);
339	plat->kcol = (u8) cols;
340	plat->krow = (u8) rows;
341	if (!plat->krow || !plat->kcol ||
342	     plat->krow > TC_KPD_ROWS || plat->kcol > TC_KPD_COLUMNS) {
343		dev_err(dev,
344			"keypad columns/rows not properly specified (%ux%u)\n",
345			plat->kcol, plat->krow);
346		return ERR_PTR(-EINVAL);
347	}
348
349	if (!of_get_property(np, "linux,keymap", &proplen)) {
350		dev_err(dev, "property linux,keymap not found\n");
351		return ERR_PTR(-ENOENT);
352	}
353
354	plat->no_autorepeat = of_property_read_bool(np, "linux,no-autorepeat");
355	plat->enable_wakeup = of_property_read_bool(np, "linux,wakeup");
356
357	/* The custom delay format is ms/16 */
358	of_property_read_u32(np, "debounce-delay-ms", &debounce_ms);
359	if (debounce_ms)
360		plat->debounce_period = debounce_ms * 16;
361	else
362		plat->debounce_period = TC_KPD_DEBOUNCE_PERIOD;
363
364	plat->settle_time = TC_KPD_SETTLE_TIME;
365	/* FIXME: should be property of the IRQ resource? */
366	plat->irqtype = IRQF_TRIGGER_FALLING;
367
368	return plat;
369}
370
371static int tc3589x_keypad_probe(struct platform_device *pdev)
372{
373	struct tc3589x *tc3589x = dev_get_drvdata(pdev->dev.parent);
374	struct tc_keypad *keypad;
375	struct input_dev *input;
376	const struct tc3589x_keypad_platform_data *plat;
377	int error, irq;
378
379	plat = tc3589x_keypad_of_probe(&pdev->dev);
380	if (IS_ERR(plat)) {
381		dev_err(&pdev->dev, "invalid keypad platform data\n");
382		return PTR_ERR(plat);
383	}
384
385	irq = platform_get_irq(pdev, 0);
386	if (irq < 0)
387		return irq;
388
389	keypad = kzalloc(sizeof(struct tc_keypad), GFP_KERNEL);
390	input = input_allocate_device();
391	if (!keypad || !input) {
392		dev_err(&pdev->dev, "failed to allocate keypad memory\n");
393		error = -ENOMEM;
394		goto err_free_mem;
395	}
396
397	keypad->board = plat;
398	keypad->input = input;
399	keypad->tc3589x = tc3589x;
400
401	input->id.bustype = BUS_I2C;
402	input->name = pdev->name;
403	input->dev.parent = &pdev->dev;
404
405	input->open = tc3589x_keypad_open;
406	input->close = tc3589x_keypad_close;
407
408	error = matrix_keypad_build_keymap(plat->keymap_data, NULL,
409					   TC3589x_MAX_KPROW, TC3589x_MAX_KPCOL,
410					   NULL, input);
411	if (error) {
412		dev_err(&pdev->dev, "Failed to build keymap\n");
413		goto err_free_mem;
414	}
415
416	keypad->keymap = input->keycode;
417
418	input_set_capability(input, EV_MSC, MSC_SCAN);
419	if (!plat->no_autorepeat)
420		__set_bit(EV_REP, input->evbit);
421
422	input_set_drvdata(input, keypad);
423
424	error = request_threaded_irq(irq, NULL, tc3589x_keypad_irq,
425				     plat->irqtype | IRQF_ONESHOT,
426				     "tc3589x-keypad", keypad);
427	if (error < 0) {
428		dev_err(&pdev->dev,
429				"Could not allocate irq %d,error %d\n",
430				irq, error);
431		goto err_free_mem;
432	}
433
434	error = input_register_device(input);
435	if (error) {
436		dev_err(&pdev->dev, "Could not register input device\n");
437		goto err_free_irq;
438	}
439
440	/* let platform decide if keypad is a wakeup source or not */
441	device_init_wakeup(&pdev->dev, plat->enable_wakeup);
442	device_set_wakeup_capable(&pdev->dev, plat->enable_wakeup);
443
444	platform_set_drvdata(pdev, keypad);
445
446	return 0;
447
448err_free_irq:
449	free_irq(irq, keypad);
450err_free_mem:
451	input_free_device(input);
452	kfree(keypad);
453	return error;
454}
455
456static int tc3589x_keypad_remove(struct platform_device *pdev)
457{
458	struct tc_keypad *keypad = platform_get_drvdata(pdev);
459	int irq = platform_get_irq(pdev, 0);
460
461	if (!keypad->keypad_stopped)
462		tc3589x_keypad_disable(keypad);
463
464	free_irq(irq, keypad);
465
466	input_unregister_device(keypad->input);
467
468	kfree(keypad);
469
470	return 0;
471}
472
473#ifdef CONFIG_PM_SLEEP
474static int tc3589x_keypad_suspend(struct device *dev)
475{
476	struct platform_device *pdev = to_platform_device(dev);
477	struct tc_keypad *keypad = platform_get_drvdata(pdev);
478	int irq = platform_get_irq(pdev, 0);
479
480	/* keypad is already off; we do nothing */
481	if (keypad->keypad_stopped)
482		return 0;
483
484	/* if device is not a wakeup source, disable it for powersave */
485	if (!device_may_wakeup(&pdev->dev))
486		tc3589x_keypad_disable(keypad);
487	else
488		enable_irq_wake(irq);
489
490	return 0;
491}
492
493static int tc3589x_keypad_resume(struct device *dev)
494{
495	struct platform_device *pdev = to_platform_device(dev);
496	struct tc_keypad *keypad = platform_get_drvdata(pdev);
497	int irq = platform_get_irq(pdev, 0);
498
499	if (!keypad->keypad_stopped)
500		return 0;
501
502	/* enable the device to resume normal operations */
503	if (!device_may_wakeup(&pdev->dev))
504		tc3589x_keypad_enable(keypad);
505	else
506		disable_irq_wake(irq);
507
508	return 0;
509}
510#endif
511
512static SIMPLE_DEV_PM_OPS(tc3589x_keypad_dev_pm_ops,
513			 tc3589x_keypad_suspend, tc3589x_keypad_resume);
514
515static struct platform_driver tc3589x_keypad_driver = {
516	.driver	= {
517		.name	= "tc3589x-keypad",
518		.pm	= &tc3589x_keypad_dev_pm_ops,
519	},
520	.probe	= tc3589x_keypad_probe,
521	.remove	= tc3589x_keypad_remove,
522};
523module_platform_driver(tc3589x_keypad_driver);
524
525MODULE_LICENSE("GPL v2");
526MODULE_AUTHOR("Jayeeta Banerjee/Sundar Iyer");
527MODULE_DESCRIPTION("TC35893 Keypad Driver");
528MODULE_ALIAS("platform:tc3589x-keypad");
529