xref: /openbmc/linux/drivers/input/keyboard/lm8323.c (revision 85ab3738)
1 /*
2  * drivers/i2c/chips/lm8323.c
3  *
4  * Copyright (C) 2007-2009 Nokia Corporation
5  *
6  * Written by Daniel Stone <daniel.stone@nokia.com>
7  *            Timo O. Karjalainen <timo.o.karjalainen@nokia.com>
8  *
9  * Updated by Felipe Balbi <felipe.balbi@nokia.com>
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation (version 2 of the License only).
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23  */
24 
25 #include <linux/module.h>
26 #include <linux/i2c.h>
27 #include <linux/interrupt.h>
28 #include <linux/sched.h>
29 #include <linux/mutex.h>
30 #include <linux/delay.h>
31 #include <linux/input.h>
32 #include <linux/leds.h>
33 #include <linux/platform_data/lm8323.h>
34 #include <linux/pm.h>
35 #include <linux/slab.h>
36 
37 /* Commands to send to the chip. */
38 #define LM8323_CMD_READ_ID		0x80 /* Read chip ID. */
39 #define LM8323_CMD_WRITE_CFG		0x81 /* Set configuration item. */
40 #define LM8323_CMD_READ_INT		0x82 /* Get interrupt status. */
41 #define LM8323_CMD_RESET		0x83 /* Reset, same as external one */
42 #define LM8323_CMD_WRITE_PORT_SEL	0x85 /* Set GPIO in/out. */
43 #define LM8323_CMD_WRITE_PORT_STATE	0x86 /* Set GPIO pullup. */
44 #define LM8323_CMD_READ_PORT_SEL	0x87 /* Get GPIO in/out. */
45 #define LM8323_CMD_READ_PORT_STATE	0x88 /* Get GPIO pullup. */
46 #define LM8323_CMD_READ_FIFO		0x89 /* Read byte from FIFO. */
47 #define LM8323_CMD_RPT_READ_FIFO	0x8a /* Read FIFO (no increment). */
48 #define LM8323_CMD_SET_ACTIVE		0x8b /* Set active time. */
49 #define LM8323_CMD_READ_ERR		0x8c /* Get error status. */
50 #define LM8323_CMD_READ_ROTATOR		0x8e /* Read rotator status. */
51 #define LM8323_CMD_SET_DEBOUNCE		0x8f /* Set debouncing time. */
52 #define LM8323_CMD_SET_KEY_SIZE		0x90 /* Set keypad size. */
53 #define LM8323_CMD_READ_KEY_SIZE	0x91 /* Get keypad size. */
54 #define LM8323_CMD_READ_CFG		0x92 /* Get configuration item. */
55 #define LM8323_CMD_WRITE_CLOCK		0x93 /* Set clock config. */
56 #define LM8323_CMD_READ_CLOCK		0x94 /* Get clock config. */
57 #define LM8323_CMD_PWM_WRITE		0x95 /* Write PWM script. */
58 #define LM8323_CMD_START_PWM		0x96 /* Start PWM engine. */
59 #define LM8323_CMD_STOP_PWM		0x97 /* Stop PWM engine. */
60 
61 /* Interrupt status. */
62 #define INT_KEYPAD			0x01 /* Key event. */
63 #define INT_ROTATOR			0x02 /* Rotator event. */
64 #define INT_ERROR			0x08 /* Error: use CMD_READ_ERR. */
65 #define INT_NOINIT			0x10 /* Lost configuration. */
66 #define INT_PWM1			0x20 /* PWM1 stopped. */
67 #define INT_PWM2			0x40 /* PWM2 stopped. */
68 #define INT_PWM3			0x80 /* PWM3 stopped. */
69 
70 /* Errors (signalled by INT_ERROR, read with CMD_READ_ERR). */
71 #define ERR_BADPAR			0x01 /* Bad parameter. */
72 #define ERR_CMDUNK			0x02 /* Unknown command. */
73 #define ERR_KEYOVR			0x04 /* Too many keys pressed. */
74 #define ERR_FIFOOVER			0x40 /* FIFO overflow. */
75 
76 /* Configuration keys (CMD_{WRITE,READ}_CFG). */
77 #define CFG_MUX1SEL			0x01 /* Select MUX1_OUT input. */
78 #define CFG_MUX1EN			0x02 /* Enable MUX1_OUT. */
79 #define CFG_MUX2SEL			0x04 /* Select MUX2_OUT input. */
80 #define CFG_MUX2EN			0x08 /* Enable MUX2_OUT. */
81 #define CFG_PSIZE			0x20 /* Package size (must be 0). */
82 #define CFG_ROTEN			0x40 /* Enable rotator. */
83 
84 /* Clock settings (CMD_{WRITE,READ}_CLOCK). */
85 #define CLK_RCPWM_INTERNAL		0x00
86 #define CLK_RCPWM_EXTERNAL		0x03
87 #define CLK_SLOWCLKEN			0x08 /* Enable 32.768kHz clock. */
88 #define CLK_SLOWCLKOUT			0x40 /* Enable slow pulse output. */
89 
90 /* The possible addresses corresponding to CONFIG1 and CONFIG2 pin wirings. */
91 #define LM8323_I2C_ADDR00		(0x84 >> 1)	/* 1000 010x */
92 #define LM8323_I2C_ADDR01		(0x86 >> 1)	/* 1000 011x */
93 #define LM8323_I2C_ADDR10		(0x88 >> 1)	/* 1000 100x */
94 #define LM8323_I2C_ADDR11		(0x8A >> 1)	/* 1000 101x */
95 
96 /* Key event fifo length */
97 #define LM8323_FIFO_LEN			15
98 
99 /* Commands for PWM engine; feed in with PWM_WRITE. */
100 /* Load ramp counter from duty cycle field (range 0 - 0xff). */
101 #define PWM_SET(v)			(0x4000 | ((v) & 0xff))
102 /* Go to start of script. */
103 #define PWM_GOTOSTART			0x0000
104 /*
105  * Stop engine (generates interrupt).  If reset is 1, clear the program
106  * counter, else leave it.
107  */
108 #define PWM_END(reset)			(0xc000 | (!!(reset) << 11))
109 /*
110  * Ramp.  If s is 1, divide clock by 512, else divide clock by 16.
111  * Take t clock scales (up to 63) per step, for n steps (up to 126).
112  * If u is set, ramp up, else ramp down.
113  */
114 #define PWM_RAMP(s, t, n, u)		((!!(s) << 14) | ((t) & 0x3f) << 8 | \
115 					 ((n) & 0x7f) | ((u) ? 0 : 0x80))
116 /*
117  * Loop (i.e. jump back to pos) for a given number of iterations (up to 63).
118  * If cnt is zero, execute until PWM_END is encountered.
119  */
120 #define PWM_LOOP(cnt, pos)		(0xa000 | (((cnt) & 0x3f) << 7) | \
121 					 ((pos) & 0x3f))
122 /*
123  * Wait for trigger.  Argument is a mask of channels, shifted by the channel
124  * number, e.g. 0xa for channels 3 and 1.  Note that channels are numbered
125  * from 1, not 0.
126  */
127 #define PWM_WAIT_TRIG(chans)		(0xe000 | (((chans) & 0x7) << 6))
128 /* Send trigger.  Argument is same as PWM_WAIT_TRIG. */
129 #define PWM_SEND_TRIG(chans)		(0xe000 | ((chans) & 0x7))
130 
131 struct lm8323_pwm {
132 	int			id;
133 	int			fade_time;
134 	int			brightness;
135 	int			desired_brightness;
136 	bool			enabled;
137 	bool			running;
138 	/* pwm lock */
139 	struct mutex		lock;
140 	struct work_struct	work;
141 	struct led_classdev	cdev;
142 	struct lm8323_chip	*chip;
143 };
144 
145 struct lm8323_chip {
146 	/* device lock */
147 	struct mutex		lock;
148 	struct i2c_client	*client;
149 	struct input_dev	*idev;
150 	bool			kp_enabled;
151 	bool			pm_suspend;
152 	unsigned		keys_down;
153 	char			phys[32];
154 	unsigned short		keymap[LM8323_KEYMAP_SIZE];
155 	int			size_x;
156 	int			size_y;
157 	int			debounce_time;
158 	int			active_time;
159 	struct lm8323_pwm	pwm[LM8323_NUM_PWMS];
160 };
161 
162 #define client_to_lm8323(c)	container_of(c, struct lm8323_chip, client)
163 #define dev_to_lm8323(d)	container_of(d, struct lm8323_chip, client->dev)
164 #define cdev_to_pwm(c)		container_of(c, struct lm8323_pwm, cdev)
165 #define work_to_pwm(w)		container_of(w, struct lm8323_pwm, work)
166 
167 #define LM8323_MAX_DATA 8
168 
169 /*
170  * To write, we just access the chip's address in write mode, and dump the
171  * command and data out on the bus.  The command byte and data are taken as
172  * sequential u8s out of varargs, to a maximum of LM8323_MAX_DATA.
173  */
174 static int lm8323_write(struct lm8323_chip *lm, int len, ...)
175 {
176 	int ret, i;
177 	va_list ap;
178 	u8 data[LM8323_MAX_DATA];
179 
180 	va_start(ap, len);
181 
182 	if (unlikely(len > LM8323_MAX_DATA)) {
183 		dev_err(&lm->client->dev, "tried to send %d bytes\n", len);
184 		va_end(ap);
185 		return 0;
186 	}
187 
188 	for (i = 0; i < len; i++)
189 		data[i] = va_arg(ap, int);
190 
191 	va_end(ap);
192 
193 	/*
194 	 * If the host is asleep while we send the data, we can get a NACK
195 	 * back while it wakes up, so try again, once.
196 	 */
197 	ret = i2c_master_send(lm->client, data, len);
198 	if (unlikely(ret == -EREMOTEIO))
199 		ret = i2c_master_send(lm->client, data, len);
200 	if (unlikely(ret != len))
201 		dev_err(&lm->client->dev, "sent %d bytes of %d total\n",
202 			len, ret);
203 
204 	return ret;
205 }
206 
207 /*
208  * To read, we first send the command byte to the chip and end the transaction,
209  * then access the chip in read mode, at which point it will send the data.
210  */
211 static int lm8323_read(struct lm8323_chip *lm, u8 cmd, u8 *buf, int len)
212 {
213 	int ret;
214 
215 	/*
216 	 * If the host is asleep while we send the byte, we can get a NACK
217 	 * back while it wakes up, so try again, once.
218 	 */
219 	ret = i2c_master_send(lm->client, &cmd, 1);
220 	if (unlikely(ret == -EREMOTEIO))
221 		ret = i2c_master_send(lm->client, &cmd, 1);
222 	if (unlikely(ret != 1)) {
223 		dev_err(&lm->client->dev, "sending read cmd 0x%02x failed\n",
224 			cmd);
225 		return 0;
226 	}
227 
228 	ret = i2c_master_recv(lm->client, buf, len);
229 	if (unlikely(ret != len))
230 		dev_err(&lm->client->dev, "wanted %d bytes, got %d\n",
231 			len, ret);
232 
233 	return ret;
234 }
235 
236 /*
237  * Set the chip active time (idle time before it enters halt).
238  */
239 static void lm8323_set_active_time(struct lm8323_chip *lm, int time)
240 {
241 	lm8323_write(lm, 2, LM8323_CMD_SET_ACTIVE, time >> 2);
242 }
243 
244 /*
245  * The signals are AT-style: the low 7 bits are the keycode, and the top
246  * bit indicates the state (1 for down, 0 for up).
247  */
248 static inline u8 lm8323_whichkey(u8 event)
249 {
250 	return event & 0x7f;
251 }
252 
253 static inline int lm8323_ispress(u8 event)
254 {
255 	return (event & 0x80) ? 1 : 0;
256 }
257 
258 static void process_keys(struct lm8323_chip *lm)
259 {
260 	u8 event;
261 	u8 key_fifo[LM8323_FIFO_LEN + 1];
262 	int old_keys_down = lm->keys_down;
263 	int ret;
264 	int i = 0;
265 
266 	/*
267 	 * Read all key events from the FIFO at once. Next READ_FIFO clears the
268 	 * FIFO even if we didn't read all events previously.
269 	 */
270 	ret = lm8323_read(lm, LM8323_CMD_READ_FIFO, key_fifo, LM8323_FIFO_LEN);
271 
272 	if (ret < 0) {
273 		dev_err(&lm->client->dev, "Failed reading fifo \n");
274 		return;
275 	}
276 	key_fifo[ret] = 0;
277 
278 	while ((event = key_fifo[i++])) {
279 		u8 key = lm8323_whichkey(event);
280 		int isdown = lm8323_ispress(event);
281 		unsigned short keycode = lm->keymap[key];
282 
283 		dev_vdbg(&lm->client->dev, "key 0x%02x %s\n",
284 			 key, isdown ? "down" : "up");
285 
286 		if (lm->kp_enabled) {
287 			input_event(lm->idev, EV_MSC, MSC_SCAN, key);
288 			input_report_key(lm->idev, keycode, isdown);
289 			input_sync(lm->idev);
290 		}
291 
292 		if (isdown)
293 			lm->keys_down++;
294 		else
295 			lm->keys_down--;
296 	}
297 
298 	/*
299 	 * Errata: We need to ensure that the chip never enters halt mode
300 	 * during a keypress, so set active time to 0.  When it's released,
301 	 * we can enter halt again, so set the active time back to normal.
302 	 */
303 	if (!old_keys_down && lm->keys_down)
304 		lm8323_set_active_time(lm, 0);
305 	if (old_keys_down && !lm->keys_down)
306 		lm8323_set_active_time(lm, lm->active_time);
307 }
308 
309 static void lm8323_process_error(struct lm8323_chip *lm)
310 {
311 	u8 error;
312 
313 	if (lm8323_read(lm, LM8323_CMD_READ_ERR, &error, 1) == 1) {
314 		if (error & ERR_FIFOOVER)
315 			dev_vdbg(&lm->client->dev, "fifo overflow!\n");
316 		if (error & ERR_KEYOVR)
317 			dev_vdbg(&lm->client->dev,
318 					"more than two keys pressed\n");
319 		if (error & ERR_CMDUNK)
320 			dev_vdbg(&lm->client->dev,
321 					"unknown command submitted\n");
322 		if (error & ERR_BADPAR)
323 			dev_vdbg(&lm->client->dev, "bad command parameter\n");
324 	}
325 }
326 
327 static void lm8323_reset(struct lm8323_chip *lm)
328 {
329 	/* The docs say we must pass 0xAA as the data byte. */
330 	lm8323_write(lm, 2, LM8323_CMD_RESET, 0xAA);
331 }
332 
333 static int lm8323_configure(struct lm8323_chip *lm)
334 {
335 	int keysize = (lm->size_x << 4) | lm->size_y;
336 	int clock = (CLK_SLOWCLKEN | CLK_RCPWM_EXTERNAL);
337 	int debounce = lm->debounce_time >> 2;
338 	int active = lm->active_time >> 2;
339 
340 	/*
341 	 * Active time must be greater than the debounce time: if it's
342 	 * a close-run thing, give ourselves a 12ms buffer.
343 	 */
344 	if (debounce >= active)
345 		active = debounce + 3;
346 
347 	lm8323_write(lm, 2, LM8323_CMD_WRITE_CFG, 0);
348 	lm8323_write(lm, 2, LM8323_CMD_WRITE_CLOCK, clock);
349 	lm8323_write(lm, 2, LM8323_CMD_SET_KEY_SIZE, keysize);
350 	lm8323_set_active_time(lm, lm->active_time);
351 	lm8323_write(lm, 2, LM8323_CMD_SET_DEBOUNCE, debounce);
352 	lm8323_write(lm, 3, LM8323_CMD_WRITE_PORT_STATE, 0xff, 0xff);
353 	lm8323_write(lm, 3, LM8323_CMD_WRITE_PORT_SEL, 0, 0);
354 
355 	/*
356 	 * Not much we can do about errors at this point, so just hope
357 	 * for the best.
358 	 */
359 
360 	return 0;
361 }
362 
363 static void pwm_done(struct lm8323_pwm *pwm)
364 {
365 	mutex_lock(&pwm->lock);
366 	pwm->running = false;
367 	if (pwm->desired_brightness != pwm->brightness)
368 		schedule_work(&pwm->work);
369 	mutex_unlock(&pwm->lock);
370 }
371 
372 /*
373  * Bottom half: handle the interrupt by posting key events, or dealing with
374  * errors appropriately.
375  */
376 static irqreturn_t lm8323_irq(int irq, void *_lm)
377 {
378 	struct lm8323_chip *lm = _lm;
379 	u8 ints;
380 	int i;
381 
382 	mutex_lock(&lm->lock);
383 
384 	while ((lm8323_read(lm, LM8323_CMD_READ_INT, &ints, 1) == 1) && ints) {
385 		if (likely(ints & INT_KEYPAD))
386 			process_keys(lm);
387 		if (ints & INT_ROTATOR) {
388 			/* We don't currently support the rotator. */
389 			dev_vdbg(&lm->client->dev, "rotator fired\n");
390 		}
391 		if (ints & INT_ERROR) {
392 			dev_vdbg(&lm->client->dev, "error!\n");
393 			lm8323_process_error(lm);
394 		}
395 		if (ints & INT_NOINIT) {
396 			dev_err(&lm->client->dev, "chip lost config; "
397 						  "reinitialising\n");
398 			lm8323_configure(lm);
399 		}
400 		for (i = 0; i < LM8323_NUM_PWMS; i++) {
401 			if (ints & (INT_PWM1 << i)) {
402 				dev_vdbg(&lm->client->dev,
403 					 "pwm%d engine completed\n", i);
404 				pwm_done(&lm->pwm[i]);
405 			}
406 		}
407 	}
408 
409 	mutex_unlock(&lm->lock);
410 
411 	return IRQ_HANDLED;
412 }
413 
414 /*
415  * Read the chip ID.
416  */
417 static int lm8323_read_id(struct lm8323_chip *lm, u8 *buf)
418 {
419 	int bytes;
420 
421 	bytes = lm8323_read(lm, LM8323_CMD_READ_ID, buf, 2);
422 	if (unlikely(bytes != 2))
423 		return -EIO;
424 
425 	return 0;
426 }
427 
428 static void lm8323_write_pwm_one(struct lm8323_pwm *pwm, int pos, u16 cmd)
429 {
430 	lm8323_write(pwm->chip, 4, LM8323_CMD_PWM_WRITE, (pos << 2) | pwm->id,
431 		     (cmd & 0xff00) >> 8, cmd & 0x00ff);
432 }
433 
434 /*
435  * Write a script into a given PWM engine, concluding with PWM_END.
436  * If 'kill' is nonzero, the engine will be shut down at the end
437  * of the script, producing a zero output. Otherwise the engine
438  * will be kept running at the final PWM level indefinitely.
439  */
440 static void lm8323_write_pwm(struct lm8323_pwm *pwm, int kill,
441 			     int len, const u16 *cmds)
442 {
443 	int i;
444 
445 	for (i = 0; i < len; i++)
446 		lm8323_write_pwm_one(pwm, i, cmds[i]);
447 
448 	lm8323_write_pwm_one(pwm, i++, PWM_END(kill));
449 	lm8323_write(pwm->chip, 2, LM8323_CMD_START_PWM, pwm->id);
450 	pwm->running = true;
451 }
452 
453 static void lm8323_pwm_work(struct work_struct *work)
454 {
455 	struct lm8323_pwm *pwm = work_to_pwm(work);
456 	int div512, perstep, steps, hz, up, kill;
457 	u16 pwm_cmds[3];
458 	int num_cmds = 0;
459 
460 	mutex_lock(&pwm->lock);
461 
462 	/*
463 	 * Do nothing if we're already at the requested level,
464 	 * or previous setting is not yet complete. In the latter
465 	 * case we will be called again when the previous PWM script
466 	 * finishes.
467 	 */
468 	if (pwm->running || pwm->desired_brightness == pwm->brightness)
469 		goto out;
470 
471 	kill = (pwm->desired_brightness == 0);
472 	up = (pwm->desired_brightness > pwm->brightness);
473 	steps = abs(pwm->desired_brightness - pwm->brightness);
474 
475 	/*
476 	 * Convert time (in ms) into a divisor (512 or 16 on a refclk of
477 	 * 32768Hz), and number of ticks per step.
478 	 */
479 	if ((pwm->fade_time / steps) > (32768 / 512)) {
480 		div512 = 1;
481 		hz = 32768 / 512;
482 	} else {
483 		div512 = 0;
484 		hz = 32768 / 16;
485 	}
486 
487 	perstep = (hz * pwm->fade_time) / (steps * 1000);
488 
489 	if (perstep == 0)
490 		perstep = 1;
491 	else if (perstep > 63)
492 		perstep = 63;
493 
494 	while (steps) {
495 		int s;
496 
497 		s = min(126, steps);
498 		pwm_cmds[num_cmds++] = PWM_RAMP(div512, perstep, s, up);
499 		steps -= s;
500 	}
501 
502 	lm8323_write_pwm(pwm, kill, num_cmds, pwm_cmds);
503 	pwm->brightness = pwm->desired_brightness;
504 
505  out:
506 	mutex_unlock(&pwm->lock);
507 }
508 
509 static void lm8323_pwm_set_brightness(struct led_classdev *led_cdev,
510 				      enum led_brightness brightness)
511 {
512 	struct lm8323_pwm *pwm = cdev_to_pwm(led_cdev);
513 	struct lm8323_chip *lm = pwm->chip;
514 
515 	mutex_lock(&pwm->lock);
516 	pwm->desired_brightness = brightness;
517 	mutex_unlock(&pwm->lock);
518 
519 	if (in_interrupt()) {
520 		schedule_work(&pwm->work);
521 	} else {
522 		/*
523 		 * Schedule PWM work as usual unless we are going into suspend
524 		 */
525 		mutex_lock(&lm->lock);
526 		if (likely(!lm->pm_suspend))
527 			schedule_work(&pwm->work);
528 		else
529 			lm8323_pwm_work(&pwm->work);
530 		mutex_unlock(&lm->lock);
531 	}
532 }
533 
534 static ssize_t lm8323_pwm_show_time(struct device *dev,
535 		struct device_attribute *attr, char *buf)
536 {
537 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
538 	struct lm8323_pwm *pwm = cdev_to_pwm(led_cdev);
539 
540 	return sprintf(buf, "%d\n", pwm->fade_time);
541 }
542 
543 static ssize_t lm8323_pwm_store_time(struct device *dev,
544 		struct device_attribute *attr, const char *buf, size_t len)
545 {
546 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
547 	struct lm8323_pwm *pwm = cdev_to_pwm(led_cdev);
548 	int ret, time;
549 
550 	ret = kstrtoint(buf, 10, &time);
551 	/* Numbers only, please. */
552 	if (ret)
553 		return ret;
554 
555 	pwm->fade_time = time;
556 
557 	return strlen(buf);
558 }
559 static DEVICE_ATTR(time, 0644, lm8323_pwm_show_time, lm8323_pwm_store_time);
560 
561 static struct attribute *lm8323_pwm_attrs[] = {
562 	&dev_attr_time.attr,
563 	NULL
564 };
565 ATTRIBUTE_GROUPS(lm8323_pwm);
566 
567 static int init_pwm(struct lm8323_chip *lm, int id, struct device *dev,
568 		    const char *name)
569 {
570 	struct lm8323_pwm *pwm;
571 
572 	BUG_ON(id > 3);
573 
574 	pwm = &lm->pwm[id - 1];
575 
576 	pwm->id = id;
577 	pwm->fade_time = 0;
578 	pwm->brightness = 0;
579 	pwm->desired_brightness = 0;
580 	pwm->running = false;
581 	pwm->enabled = false;
582 	INIT_WORK(&pwm->work, lm8323_pwm_work);
583 	mutex_init(&pwm->lock);
584 	pwm->chip = lm;
585 
586 	if (name) {
587 		pwm->cdev.name = name;
588 		pwm->cdev.brightness_set = lm8323_pwm_set_brightness;
589 		pwm->cdev.groups = lm8323_pwm_groups;
590 		if (led_classdev_register(dev, &pwm->cdev) < 0) {
591 			dev_err(dev, "couldn't register PWM %d\n", id);
592 			return -1;
593 		}
594 		pwm->enabled = true;
595 	}
596 
597 	return 0;
598 }
599 
600 static struct i2c_driver lm8323_i2c_driver;
601 
602 static ssize_t lm8323_show_disable(struct device *dev,
603 				   struct device_attribute *attr, char *buf)
604 {
605 	struct lm8323_chip *lm = dev_get_drvdata(dev);
606 
607 	return sprintf(buf, "%u\n", !lm->kp_enabled);
608 }
609 
610 static ssize_t lm8323_set_disable(struct device *dev,
611 				  struct device_attribute *attr,
612 				  const char *buf, size_t count)
613 {
614 	struct lm8323_chip *lm = dev_get_drvdata(dev);
615 	int ret;
616 	unsigned int i;
617 
618 	ret = kstrtouint(buf, 10, &i);
619 	if (ret)
620 		return ret;
621 
622 	mutex_lock(&lm->lock);
623 	lm->kp_enabled = !i;
624 	mutex_unlock(&lm->lock);
625 
626 	return count;
627 }
628 static DEVICE_ATTR(disable_kp, 0644, lm8323_show_disable, lm8323_set_disable);
629 
630 static int lm8323_probe(struct i2c_client *client,
631 				  const struct i2c_device_id *id)
632 {
633 	struct lm8323_platform_data *pdata = dev_get_platdata(&client->dev);
634 	struct input_dev *idev;
635 	struct lm8323_chip *lm;
636 	int pwm;
637 	int i, err;
638 	unsigned long tmo;
639 	u8 data[2];
640 
641 	if (!pdata || !pdata->size_x || !pdata->size_y) {
642 		dev_err(&client->dev, "missing platform_data\n");
643 		return -EINVAL;
644 	}
645 
646 	if (pdata->size_x > 8) {
647 		dev_err(&client->dev, "invalid x size %d specified\n",
648 			pdata->size_x);
649 		return -EINVAL;
650 	}
651 
652 	if (pdata->size_y > 12) {
653 		dev_err(&client->dev, "invalid y size %d specified\n",
654 			pdata->size_y);
655 		return -EINVAL;
656 	}
657 
658 	lm = kzalloc(sizeof *lm, GFP_KERNEL);
659 	idev = input_allocate_device();
660 	if (!lm || !idev) {
661 		err = -ENOMEM;
662 		goto fail1;
663 	}
664 
665 	lm->client = client;
666 	lm->idev = idev;
667 	mutex_init(&lm->lock);
668 
669 	lm->size_x = pdata->size_x;
670 	lm->size_y = pdata->size_y;
671 	dev_vdbg(&client->dev, "Keypad size: %d x %d\n",
672 		 lm->size_x, lm->size_y);
673 
674 	lm->debounce_time = pdata->debounce_time;
675 	lm->active_time = pdata->active_time;
676 
677 	lm8323_reset(lm);
678 
679 	/* Nothing's set up to service the IRQ yet, so just spin for max.
680 	 * 100ms until we can configure. */
681 	tmo = jiffies + msecs_to_jiffies(100);
682 	while (lm8323_read(lm, LM8323_CMD_READ_INT, data, 1) == 1) {
683 		if (data[0] & INT_NOINIT)
684 			break;
685 
686 		if (time_after(jiffies, tmo)) {
687 			dev_err(&client->dev,
688 				"timeout waiting for initialisation\n");
689 			break;
690 		}
691 
692 		msleep(1);
693 	}
694 
695 	lm8323_configure(lm);
696 
697 	/* If a true probe check the device */
698 	if (lm8323_read_id(lm, data) != 0) {
699 		dev_err(&client->dev, "device not found\n");
700 		err = -ENODEV;
701 		goto fail1;
702 	}
703 
704 	for (pwm = 0; pwm < LM8323_NUM_PWMS; pwm++) {
705 		err = init_pwm(lm, pwm + 1, &client->dev,
706 			       pdata->pwm_names[pwm]);
707 		if (err < 0)
708 			goto fail2;
709 	}
710 
711 	lm->kp_enabled = true;
712 	err = device_create_file(&client->dev, &dev_attr_disable_kp);
713 	if (err < 0)
714 		goto fail2;
715 
716 	idev->name = pdata->name ? : "LM8323 keypad";
717 	snprintf(lm->phys, sizeof(lm->phys),
718 		 "%s/input-kp", dev_name(&client->dev));
719 	idev->phys = lm->phys;
720 
721 	idev->evbit[0] = BIT(EV_KEY) | BIT(EV_MSC);
722 	__set_bit(MSC_SCAN, idev->mscbit);
723 	for (i = 0; i < LM8323_KEYMAP_SIZE; i++) {
724 		__set_bit(pdata->keymap[i], idev->keybit);
725 		lm->keymap[i] = pdata->keymap[i];
726 	}
727 	__clear_bit(KEY_RESERVED, idev->keybit);
728 
729 	if (pdata->repeat)
730 		__set_bit(EV_REP, idev->evbit);
731 
732 	err = input_register_device(idev);
733 	if (err) {
734 		dev_dbg(&client->dev, "error registering input device\n");
735 		goto fail3;
736 	}
737 
738 	err = request_threaded_irq(client->irq, NULL, lm8323_irq,
739 			  IRQF_TRIGGER_LOW|IRQF_ONESHOT, "lm8323", lm);
740 	if (err) {
741 		dev_err(&client->dev, "could not get IRQ %d\n", client->irq);
742 		goto fail4;
743 	}
744 
745 	i2c_set_clientdata(client, lm);
746 
747 	device_init_wakeup(&client->dev, 1);
748 	enable_irq_wake(client->irq);
749 
750 	return 0;
751 
752 fail4:
753 	input_unregister_device(idev);
754 	idev = NULL;
755 fail3:
756 	device_remove_file(&client->dev, &dev_attr_disable_kp);
757 fail2:
758 	while (--pwm >= 0)
759 		if (lm->pwm[pwm].enabled)
760 			led_classdev_unregister(&lm->pwm[pwm].cdev);
761 fail1:
762 	input_free_device(idev);
763 	kfree(lm);
764 	return err;
765 }
766 
767 static int lm8323_remove(struct i2c_client *client)
768 {
769 	struct lm8323_chip *lm = i2c_get_clientdata(client);
770 	int i;
771 
772 	disable_irq_wake(client->irq);
773 	free_irq(client->irq, lm);
774 
775 	input_unregister_device(lm->idev);
776 
777 	device_remove_file(&lm->client->dev, &dev_attr_disable_kp);
778 
779 	for (i = 0; i < 3; i++)
780 		if (lm->pwm[i].enabled)
781 			led_classdev_unregister(&lm->pwm[i].cdev);
782 
783 	kfree(lm);
784 
785 	return 0;
786 }
787 
788 #ifdef CONFIG_PM_SLEEP
789 /*
790  * We don't need to explicitly suspend the chip, as it already switches off
791  * when there's no activity.
792  */
793 static int lm8323_suspend(struct device *dev)
794 {
795 	struct i2c_client *client = to_i2c_client(dev);
796 	struct lm8323_chip *lm = i2c_get_clientdata(client);
797 	int i;
798 
799 	irq_set_irq_wake(client->irq, 0);
800 	disable_irq(client->irq);
801 
802 	mutex_lock(&lm->lock);
803 	lm->pm_suspend = true;
804 	mutex_unlock(&lm->lock);
805 
806 	for (i = 0; i < 3; i++)
807 		if (lm->pwm[i].enabled)
808 			led_classdev_suspend(&lm->pwm[i].cdev);
809 
810 	return 0;
811 }
812 
813 static int lm8323_resume(struct device *dev)
814 {
815 	struct i2c_client *client = to_i2c_client(dev);
816 	struct lm8323_chip *lm = i2c_get_clientdata(client);
817 	int i;
818 
819 	mutex_lock(&lm->lock);
820 	lm->pm_suspend = false;
821 	mutex_unlock(&lm->lock);
822 
823 	for (i = 0; i < 3; i++)
824 		if (lm->pwm[i].enabled)
825 			led_classdev_resume(&lm->pwm[i].cdev);
826 
827 	enable_irq(client->irq);
828 	irq_set_irq_wake(client->irq, 1);
829 
830 	return 0;
831 }
832 #endif
833 
834 static SIMPLE_DEV_PM_OPS(lm8323_pm_ops, lm8323_suspend, lm8323_resume);
835 
836 static const struct i2c_device_id lm8323_id[] = {
837 	{ "lm8323", 0 },
838 	{ }
839 };
840 
841 static struct i2c_driver lm8323_i2c_driver = {
842 	.driver = {
843 		.name	= "lm8323",
844 		.pm	= &lm8323_pm_ops,
845 	},
846 	.probe		= lm8323_probe,
847 	.remove		= lm8323_remove,
848 	.id_table	= lm8323_id,
849 };
850 MODULE_DEVICE_TABLE(i2c, lm8323_id);
851 
852 module_i2c_driver(lm8323_i2c_driver);
853 
854 MODULE_AUTHOR("Timo O. Karjalainen <timo.o.karjalainen@nokia.com>");
855 MODULE_AUTHOR("Daniel Stone");
856 MODULE_AUTHOR("Felipe Balbi <felipe.balbi@nokia.com>");
857 MODULE_DESCRIPTION("LM8323 keypad driver");
858 MODULE_LICENSE("GPL");
859 
860