xref: /linux/drivers/input/keyboard/tc3589x-keypad.c (revision b43ab901d671e3e3cad425ea5e9a3c74e266dcdd)
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/init.h>
14 #include <linux/interrupt.h>
15 #include <linux/input.h>
16 #include <linux/platform_device.h>
17 #include <linux/input/matrix_keypad.h>
18 #include <linux/i2c.h>
19 #include <linux/slab.h>
20 #include <linux/mfd/tc3589x.h>
21 
22 /* Maximum supported keypad matrix row/columns size */
23 #define TC3589x_MAX_KPROW               8
24 #define TC3589x_MAX_KPCOL               12
25 
26 /* keypad related Constants */
27 #define TC3589x_MAX_DEBOUNCE_SETTLE     0xFF
28 #define DEDICATED_KEY_VAL		0xFF
29 
30 /* Pull up/down masks */
31 #define TC3589x_NO_PULL_MASK		0x0
32 #define TC3589x_PULL_DOWN_MASK		0x1
33 #define TC3589x_PULL_UP_MASK		0x2
34 #define TC3589x_PULLUP_ALL_MASK		0xAA
35 #define TC3589x_IO_PULL_VAL(index, mask)	((mask)<<((index)%4)*2))
36 
37 /* Bit masks for IOCFG register */
38 #define IOCFG_BALLCFG		0x01
39 #define IOCFG_IG		0x08
40 
41 #define KP_EVCODE_COL_MASK	0x0F
42 #define KP_EVCODE_ROW_MASK	0x70
43 #define KP_RELEASE_EVT_MASK	0x80
44 
45 #define KP_ROW_SHIFT		4
46 
47 #define KP_NO_VALID_KEY_MASK	0x7F
48 
49 /* bit masks for RESTCTRL register */
50 #define TC3589x_KBDRST		0x2
51 #define TC3589x_IRQRST		0x10
52 #define TC3589x_RESET_ALL	0x1B
53 
54 /* KBDMFS register bit mask */
55 #define TC3589x_KBDMFS_EN	0x1
56 
57 /* CLKEN register bitmask */
58 #define KPD_CLK_EN		0x1
59 
60 /* RSTINTCLR register bit mask */
61 #define IRQ_CLEAR		0x1
62 
63 /* bit masks for keyboard interrupts*/
64 #define TC3589x_EVT_LOSS_INT	0x8
65 #define TC3589x_EVT_INT		0x4
66 #define TC3589x_KBD_LOSS_INT	0x2
67 #define TC3589x_KBD_INT		0x1
68 
69 /* bit masks for keyboard interrupt clear*/
70 #define TC3589x_EVT_INT_CLR	0x2
71 #define TC3589x_KBD_INT_CLR	0x1
72 
73 #define TC3589x_KBD_KEYMAP_SIZE     64
74 
75 /**
76  * struct tc_keypad - data structure used by keypad driver
77  * @tc3589x:    pointer to tc35893
78  * @input:      pointer to input device object
79  * @board:      keypad platform device
80  * @krow:	number of rows
81  * @kcol:	number of coloumns
82  * @keymap:     matrix scan code table for keycodes
83  * @keypad_stopped: holds keypad status
84  */
85 struct tc_keypad {
86 	struct tc3589x *tc3589x;
87 	struct input_dev *input;
88 	const struct tc3589x_keypad_platform_data *board;
89 	unsigned int krow;
90 	unsigned int kcol;
91 	unsigned short keymap[TC3589x_KBD_KEYMAP_SIZE];
92 	bool keypad_stopped;
93 };
94 
95 static int tc3589x_keypad_init_key_hardware(struct tc_keypad *keypad)
96 {
97 	int ret;
98 	struct tc3589x *tc3589x = keypad->tc3589x;
99 	u8 settle_time = keypad->board->settle_time;
100 	u8 dbounce_period = keypad->board->debounce_period;
101 	u8 rows = keypad->board->krow & 0xf;	/* mask out the nibble */
102 	u8 column = keypad->board->kcol & 0xf;	/* mask out the nibble */
103 
104 	/* validate platform configurations */
105 	if (keypad->board->kcol > TC3589x_MAX_KPCOL ||
106 	    keypad->board->krow > TC3589x_MAX_KPROW ||
107 	    keypad->board->debounce_period > TC3589x_MAX_DEBOUNCE_SETTLE ||
108 	    keypad->board->settle_time > TC3589x_MAX_DEBOUNCE_SETTLE)
109 		return -EINVAL;
110 
111 	/* configure KBDSIZE 4 LSbits for cols and 4 MSbits for rows */
112 	ret = tc3589x_reg_write(tc3589x, TC3589x_KBDSIZE,
113 			(rows << KP_ROW_SHIFT) | column);
114 	if (ret < 0)
115 		return ret;
116 
117 	/* configure dedicated key config, no dedicated key selected */
118 	ret = tc3589x_reg_write(tc3589x, TC3589x_KBCFG_LSB, DEDICATED_KEY_VAL);
119 	if (ret < 0)
120 		return ret;
121 
122 	ret = tc3589x_reg_write(tc3589x, TC3589x_KBCFG_MSB, DEDICATED_KEY_VAL);
123 	if (ret < 0)
124 		return ret;
125 
126 	/* Configure settle time */
127 	ret = tc3589x_reg_write(tc3589x, TC3589x_KBDSETTLE_REG, settle_time);
128 	if (ret < 0)
129 		return ret;
130 
131 	/* Configure debounce time */
132 	ret = tc3589x_reg_write(tc3589x, TC3589x_KBDBOUNCE, dbounce_period);
133 	if (ret < 0)
134 		return ret;
135 
136 	/* Start of initialise keypad GPIOs */
137 	ret = tc3589x_set_bits(tc3589x, TC3589x_IOCFG, 0x0, IOCFG_IG);
138 	if (ret < 0)
139 		return ret;
140 
141 	/* Configure pull-up resistors for all row GPIOs */
142 	ret = tc3589x_reg_write(tc3589x, TC3589x_IOPULLCFG0_LSB,
143 					TC3589x_PULLUP_ALL_MASK);
144 	if (ret < 0)
145 		return ret;
146 
147 	ret = tc3589x_reg_write(tc3589x, TC3589x_IOPULLCFG0_MSB,
148 					TC3589x_PULLUP_ALL_MASK);
149 	if (ret < 0)
150 		return ret;
151 
152 	/* Configure pull-up resistors for all column GPIOs */
153 	ret = tc3589x_reg_write(tc3589x, TC3589x_IOPULLCFG1_LSB,
154 			TC3589x_PULLUP_ALL_MASK);
155 	if (ret < 0)
156 		return ret;
157 
158 	ret = tc3589x_reg_write(tc3589x, TC3589x_IOPULLCFG1_MSB,
159 			TC3589x_PULLUP_ALL_MASK);
160 	if (ret < 0)
161 		return ret;
162 
163 	ret = tc3589x_reg_write(tc3589x, TC3589x_IOPULLCFG2_LSB,
164 			TC3589x_PULLUP_ALL_MASK);
165 
166 	return ret;
167 }
168 
169 #define TC35893_DATA_REGS		4
170 #define TC35893_KEYCODE_FIFO_EMPTY	0x7f
171 #define TC35893_KEYCODE_FIFO_CLEAR	0xff
172 #define TC35893_KEYPAD_ROW_SHIFT	0x3
173 
174 static irqreturn_t tc3589x_keypad_irq(int irq, void *dev)
175 {
176 	struct tc_keypad *keypad = dev;
177 	struct tc3589x *tc3589x = keypad->tc3589x;
178 	u8 i, row_index, col_index, kbd_code, up;
179 	u8 code;
180 
181 	for (i = 0; i < TC35893_DATA_REGS * 2; i++) {
182 		kbd_code = tc3589x_reg_read(tc3589x, TC3589x_EVTCODE_FIFO);
183 
184 		/* loop till fifo is empty and no more keys are pressed */
185 		if (kbd_code == TC35893_KEYCODE_FIFO_EMPTY ||
186 				kbd_code == TC35893_KEYCODE_FIFO_CLEAR)
187 			continue;
188 
189 		/* valid key is found */
190 		col_index = kbd_code & KP_EVCODE_COL_MASK;
191 		row_index = (kbd_code & KP_EVCODE_ROW_MASK) >> KP_ROW_SHIFT;
192 		code = MATRIX_SCAN_CODE(row_index, col_index,
193 						TC35893_KEYPAD_ROW_SHIFT);
194 		up = kbd_code & KP_RELEASE_EVT_MASK;
195 
196 		input_event(keypad->input, EV_MSC, MSC_SCAN, code);
197 		input_report_key(keypad->input, keypad->keymap[code], !up);
198 		input_sync(keypad->input);
199 	}
200 
201 	/* clear IRQ */
202 	tc3589x_set_bits(tc3589x, TC3589x_KBDIC,
203 			0x0, TC3589x_EVT_INT_CLR | TC3589x_KBD_INT_CLR);
204 	/* enable IRQ */
205 	tc3589x_set_bits(tc3589x, TC3589x_KBDMSK,
206 			0x0, TC3589x_EVT_LOSS_INT | TC3589x_EVT_INT);
207 
208 	return IRQ_HANDLED;
209 }
210 
211 static int tc3589x_keypad_enable(struct tc_keypad *keypad)
212 {
213 	struct tc3589x *tc3589x = keypad->tc3589x;
214 	int ret;
215 
216 	/* pull the keypad module out of reset */
217 	ret = tc3589x_set_bits(tc3589x, TC3589x_RSTCTRL, TC3589x_KBDRST, 0x0);
218 	if (ret < 0)
219 		return ret;
220 
221 	/* configure KBDMFS */
222 	ret = tc3589x_set_bits(tc3589x, TC3589x_KBDMFS, 0x0, TC3589x_KBDMFS_EN);
223 	if (ret < 0)
224 		return ret;
225 
226 	/* enable the keypad clock */
227 	ret = tc3589x_set_bits(tc3589x, TC3589x_CLKEN, 0x0, KPD_CLK_EN);
228 	if (ret < 0)
229 		return ret;
230 
231 	/* clear pending IRQs */
232 	ret =  tc3589x_set_bits(tc3589x, TC3589x_RSTINTCLR, 0x0, 0x1);
233 	if (ret < 0)
234 		return ret;
235 
236 	/* enable the IRQs */
237 	ret = tc3589x_set_bits(tc3589x, TC3589x_KBDMSK, 0x0,
238 					TC3589x_EVT_LOSS_INT | TC3589x_EVT_INT);
239 	if (ret < 0)
240 		return ret;
241 
242 	keypad->keypad_stopped = false;
243 
244 	return ret;
245 }
246 
247 static int tc3589x_keypad_disable(struct tc_keypad *keypad)
248 {
249 	struct tc3589x *tc3589x = keypad->tc3589x;
250 	int ret;
251 
252 	/* clear IRQ */
253 	ret = tc3589x_set_bits(tc3589x, TC3589x_KBDIC,
254 			0x0, TC3589x_EVT_INT_CLR | TC3589x_KBD_INT_CLR);
255 	if (ret < 0)
256 		return ret;
257 
258 	/* disable all interrupts */
259 	ret = tc3589x_set_bits(tc3589x, TC3589x_KBDMSK,
260 			~(TC3589x_EVT_LOSS_INT | TC3589x_EVT_INT), 0x0);
261 	if (ret < 0)
262 		return ret;
263 
264 	/* disable the keypad module */
265 	ret = tc3589x_set_bits(tc3589x, TC3589x_CLKEN, 0x1, 0x0);
266 	if (ret < 0)
267 		return ret;
268 
269 	/* put the keypad module into reset */
270 	ret = tc3589x_set_bits(tc3589x, TC3589x_RSTCTRL, TC3589x_KBDRST, 0x1);
271 
272 	keypad->keypad_stopped = true;
273 
274 	return ret;
275 }
276 
277 static int tc3589x_keypad_open(struct input_dev *input)
278 {
279 	int error;
280 	struct tc_keypad *keypad = input_get_drvdata(input);
281 
282 	/* enable the keypad module */
283 	error = tc3589x_keypad_enable(keypad);
284 	if (error < 0) {
285 		dev_err(&input->dev, "failed to enable keypad module\n");
286 		return error;
287 	}
288 
289 	error = tc3589x_keypad_init_key_hardware(keypad);
290 	if (error < 0) {
291 		dev_err(&input->dev, "failed to configure keypad module\n");
292 		return error;
293 	}
294 
295 	return 0;
296 }
297 
298 static void tc3589x_keypad_close(struct input_dev *input)
299 {
300 	struct tc_keypad *keypad = input_get_drvdata(input);
301 
302 	/* disable the keypad module */
303 	tc3589x_keypad_disable(keypad);
304 }
305 
306 static int __devinit tc3589x_keypad_probe(struct platform_device *pdev)
307 {
308 	struct tc3589x *tc3589x = dev_get_drvdata(pdev->dev.parent);
309 	struct tc_keypad *keypad;
310 	struct input_dev *input;
311 	const struct tc3589x_keypad_platform_data *plat;
312 	int error, irq;
313 
314 	plat = tc3589x->pdata->keypad;
315 	if (!plat) {
316 		dev_err(&pdev->dev, "invalid keypad platform data\n");
317 		return -EINVAL;
318 	}
319 
320 	irq = platform_get_irq(pdev, 0);
321 	if (irq < 0)
322 		return irq;
323 
324 	keypad = kzalloc(sizeof(struct tc_keypad), GFP_KERNEL);
325 	input = input_allocate_device();
326 	if (!keypad || !input) {
327 		dev_err(&pdev->dev, "failed to allocate keypad memory\n");
328 		error = -ENOMEM;
329 		goto err_free_mem;
330 	}
331 
332 	keypad->board = plat;
333 	keypad->input = input;
334 	keypad->tc3589x = tc3589x;
335 
336 	input->id.bustype = BUS_I2C;
337 	input->name = pdev->name;
338 	input->dev.parent = &pdev->dev;
339 
340 	input->keycode = keypad->keymap;
341 	input->keycodesize = sizeof(keypad->keymap[0]);
342 	input->keycodemax = ARRAY_SIZE(keypad->keymap);
343 
344 	input->open = tc3589x_keypad_open;
345 	input->close = tc3589x_keypad_close;
346 
347 	input_set_drvdata(input, keypad);
348 
349 	input_set_capability(input, EV_MSC, MSC_SCAN);
350 
351 	__set_bit(EV_KEY, input->evbit);
352 	if (!plat->no_autorepeat)
353 		__set_bit(EV_REP, input->evbit);
354 
355 	matrix_keypad_build_keymap(plat->keymap_data, 0x3,
356 			input->keycode, input->keybit);
357 
358 	error = request_threaded_irq(irq, NULL,
359 			tc3589x_keypad_irq, plat->irqtype,
360 			"tc3589x-keypad", keypad);
361 	if (error < 0) {
362 		dev_err(&pdev->dev,
363 				"Could not allocate irq %d,error %d\n",
364 				irq, error);
365 		goto err_free_mem;
366 	}
367 
368 	error = input_register_device(input);
369 	if (error) {
370 		dev_err(&pdev->dev, "Could not register input device\n");
371 		goto err_free_irq;
372 	}
373 
374 	/* let platform decide if keypad is a wakeup source or not */
375 	device_init_wakeup(&pdev->dev, plat->enable_wakeup);
376 	device_set_wakeup_capable(&pdev->dev, plat->enable_wakeup);
377 
378 	platform_set_drvdata(pdev, keypad);
379 
380 	return 0;
381 
382 err_free_irq:
383 	free_irq(irq, keypad);
384 err_free_mem:
385 	input_free_device(input);
386 	kfree(keypad);
387 	return error;
388 }
389 
390 static int __devexit tc3589x_keypad_remove(struct platform_device *pdev)
391 {
392 	struct tc_keypad *keypad = platform_get_drvdata(pdev);
393 	int irq = platform_get_irq(pdev, 0);
394 
395 	if (!keypad->keypad_stopped)
396 		tc3589x_keypad_disable(keypad);
397 
398 	free_irq(irq, keypad);
399 
400 	input_unregister_device(keypad->input);
401 
402 	kfree(keypad);
403 
404 	return 0;
405 }
406 
407 #ifdef CONFIG_PM_SLEEP
408 static int tc3589x_keypad_suspend(struct device *dev)
409 {
410 	struct platform_device *pdev = to_platform_device(dev);
411 	struct tc_keypad *keypad = platform_get_drvdata(pdev);
412 	int irq = platform_get_irq(pdev, 0);
413 
414 	/* keypad is already off; we do nothing */
415 	if (keypad->keypad_stopped)
416 		return 0;
417 
418 	/* if device is not a wakeup source, disable it for powersave */
419 	if (!device_may_wakeup(&pdev->dev))
420 		tc3589x_keypad_disable(keypad);
421 	else
422 		enable_irq_wake(irq);
423 
424 	return 0;
425 }
426 
427 static int tc3589x_keypad_resume(struct device *dev)
428 {
429 	struct platform_device *pdev = to_platform_device(dev);
430 	struct tc_keypad *keypad = platform_get_drvdata(pdev);
431 	int irq = platform_get_irq(pdev, 0);
432 
433 	if (!keypad->keypad_stopped)
434 		return 0;
435 
436 	/* enable the device to resume normal operations */
437 	if (!device_may_wakeup(&pdev->dev))
438 		tc3589x_keypad_enable(keypad);
439 	else
440 		disable_irq_wake(irq);
441 
442 	return 0;
443 }
444 #endif
445 
446 static SIMPLE_DEV_PM_OPS(tc3589x_keypad_dev_pm_ops,
447 			 tc3589x_keypad_suspend, tc3589x_keypad_resume);
448 
449 static struct platform_driver tc3589x_keypad_driver = {
450 	.driver	= {
451 		.name	= "tc3589x-keypad",
452 		.owner	= THIS_MODULE,
453 		.pm	= &tc3589x_keypad_dev_pm_ops,
454 	},
455 	.probe	= tc3589x_keypad_probe,
456 	.remove	= __devexit_p(tc3589x_keypad_remove),
457 };
458 module_platform_driver(tc3589x_keypad_driver);
459 
460 MODULE_LICENSE("GPL v2");
461 MODULE_AUTHOR("Jayeeta Banerjee/Sundar Iyer");
462 MODULE_DESCRIPTION("TC35893 Keypad Driver");
463 MODULE_ALIAS("platform:tc3589x-keypad");
464