xref: /openbmc/linux/drivers/input/keyboard/lm8323.c (revision c900529f3d9161bfde5cca0754f83b4d3c3e0220)
1  // SPDX-License-Identifier: GPL-2.0-only
2  /*
3   * drivers/i2c/chips/lm8323.c
4   *
5   * Copyright (C) 2007-2009 Nokia Corporation
6   *
7   * Written by Daniel Stone <daniel.stone@nokia.com>
8   *            Timo O. Karjalainen <timo.o.karjalainen@nokia.com>
9   *
10   * Updated by Felipe Balbi <felipe.balbi@nokia.com>
11   */
12  
13  #include <linux/module.h>
14  #include <linux/i2c.h>
15  #include <linux/interrupt.h>
16  #include <linux/sched.h>
17  #include <linux/mutex.h>
18  #include <linux/delay.h>
19  #include <linux/input.h>
20  #include <linux/leds.h>
21  #include <linux/platform_data/lm8323.h>
22  #include <linux/pm.h>
23  #include <linux/slab.h>
24  
25  /* Commands to send to the chip. */
26  #define LM8323_CMD_READ_ID		0x80 /* Read chip ID. */
27  #define LM8323_CMD_WRITE_CFG		0x81 /* Set configuration item. */
28  #define LM8323_CMD_READ_INT		0x82 /* Get interrupt status. */
29  #define LM8323_CMD_RESET		0x83 /* Reset, same as external one */
30  #define LM8323_CMD_WRITE_PORT_SEL	0x85 /* Set GPIO in/out. */
31  #define LM8323_CMD_WRITE_PORT_STATE	0x86 /* Set GPIO pullup. */
32  #define LM8323_CMD_READ_PORT_SEL	0x87 /* Get GPIO in/out. */
33  #define LM8323_CMD_READ_PORT_STATE	0x88 /* Get GPIO pullup. */
34  #define LM8323_CMD_READ_FIFO		0x89 /* Read byte from FIFO. */
35  #define LM8323_CMD_RPT_READ_FIFO	0x8a /* Read FIFO (no increment). */
36  #define LM8323_CMD_SET_ACTIVE		0x8b /* Set active time. */
37  #define LM8323_CMD_READ_ERR		0x8c /* Get error status. */
38  #define LM8323_CMD_READ_ROTATOR		0x8e /* Read rotator status. */
39  #define LM8323_CMD_SET_DEBOUNCE		0x8f /* Set debouncing time. */
40  #define LM8323_CMD_SET_KEY_SIZE		0x90 /* Set keypad size. */
41  #define LM8323_CMD_READ_KEY_SIZE	0x91 /* Get keypad size. */
42  #define LM8323_CMD_READ_CFG		0x92 /* Get configuration item. */
43  #define LM8323_CMD_WRITE_CLOCK		0x93 /* Set clock config. */
44  #define LM8323_CMD_READ_CLOCK		0x94 /* Get clock config. */
45  #define LM8323_CMD_PWM_WRITE		0x95 /* Write PWM script. */
46  #define LM8323_CMD_START_PWM		0x96 /* Start PWM engine. */
47  #define LM8323_CMD_STOP_PWM		0x97 /* Stop PWM engine. */
48  
49  /* Interrupt status. */
50  #define INT_KEYPAD			0x01 /* Key event. */
51  #define INT_ROTATOR			0x02 /* Rotator event. */
52  #define INT_ERROR			0x08 /* Error: use CMD_READ_ERR. */
53  #define INT_NOINIT			0x10 /* Lost configuration. */
54  #define INT_PWM1			0x20 /* PWM1 stopped. */
55  #define INT_PWM2			0x40 /* PWM2 stopped. */
56  #define INT_PWM3			0x80 /* PWM3 stopped. */
57  
58  /* Errors (signalled by INT_ERROR, read with CMD_READ_ERR). */
59  #define ERR_BADPAR			0x01 /* Bad parameter. */
60  #define ERR_CMDUNK			0x02 /* Unknown command. */
61  #define ERR_KEYOVR			0x04 /* Too many keys pressed. */
62  #define ERR_FIFOOVER			0x40 /* FIFO overflow. */
63  
64  /* Configuration keys (CMD_{WRITE,READ}_CFG). */
65  #define CFG_MUX1SEL			0x01 /* Select MUX1_OUT input. */
66  #define CFG_MUX1EN			0x02 /* Enable MUX1_OUT. */
67  #define CFG_MUX2SEL			0x04 /* Select MUX2_OUT input. */
68  #define CFG_MUX2EN			0x08 /* Enable MUX2_OUT. */
69  #define CFG_PSIZE			0x20 /* Package size (must be 0). */
70  #define CFG_ROTEN			0x40 /* Enable rotator. */
71  
72  /* Clock settings (CMD_{WRITE,READ}_CLOCK). */
73  #define CLK_RCPWM_INTERNAL		0x00
74  #define CLK_RCPWM_EXTERNAL		0x03
75  #define CLK_SLOWCLKEN			0x08 /* Enable 32.768kHz clock. */
76  #define CLK_SLOWCLKOUT			0x40 /* Enable slow pulse output. */
77  
78  /* The possible addresses corresponding to CONFIG1 and CONFIG2 pin wirings. */
79  #define LM8323_I2C_ADDR00		(0x84 >> 1)	/* 1000 010x */
80  #define LM8323_I2C_ADDR01		(0x86 >> 1)	/* 1000 011x */
81  #define LM8323_I2C_ADDR10		(0x88 >> 1)	/* 1000 100x */
82  #define LM8323_I2C_ADDR11		(0x8A >> 1)	/* 1000 101x */
83  
84  /* Key event fifo length */
85  #define LM8323_FIFO_LEN			15
86  
87  /* Commands for PWM engine; feed in with PWM_WRITE. */
88  /* Load ramp counter from duty cycle field (range 0 - 0xff). */
89  #define PWM_SET(v)			(0x4000 | ((v) & 0xff))
90  /* Go to start of script. */
91  #define PWM_GOTOSTART			0x0000
92  /*
93   * Stop engine (generates interrupt).  If reset is 1, clear the program
94   * counter, else leave it.
95   */
96  #define PWM_END(reset)			(0xc000 | (!!(reset) << 11))
97  /*
98   * Ramp.  If s is 1, divide clock by 512, else divide clock by 16.
99   * Take t clock scales (up to 63) per step, for n steps (up to 126).
100   * If u is set, ramp up, else ramp down.
101   */
102  #define PWM_RAMP(s, t, n, u)		((!!(s) << 14) | ((t) & 0x3f) << 8 | \
103  					 ((n) & 0x7f) | ((u) ? 0 : 0x80))
104  /*
105   * Loop (i.e. jump back to pos) for a given number of iterations (up to 63).
106   * If cnt is zero, execute until PWM_END is encountered.
107   */
108  #define PWM_LOOP(cnt, pos)		(0xa000 | (((cnt) & 0x3f) << 7) | \
109  					 ((pos) & 0x3f))
110  /*
111   * Wait for trigger.  Argument is a mask of channels, shifted by the channel
112   * number, e.g. 0xa for channels 3 and 1.  Note that channels are numbered
113   * from 1, not 0.
114   */
115  #define PWM_WAIT_TRIG(chans)		(0xe000 | (((chans) & 0x7) << 6))
116  /* Send trigger.  Argument is same as PWM_WAIT_TRIG. */
117  #define PWM_SEND_TRIG(chans)		(0xe000 | ((chans) & 0x7))
118  
119  struct lm8323_pwm {
120  	int			id;
121  	int			fade_time;
122  	int			brightness;
123  	int			desired_brightness;
124  	bool			enabled;
125  	bool			running;
126  	/* pwm lock */
127  	struct mutex		lock;
128  	struct work_struct	work;
129  	struct led_classdev	cdev;
130  	struct lm8323_chip	*chip;
131  };
132  
133  struct lm8323_chip {
134  	/* device lock */
135  	struct mutex		lock;
136  	struct i2c_client	*client;
137  	struct input_dev	*idev;
138  	bool			kp_enabled;
139  	bool			pm_suspend;
140  	unsigned		keys_down;
141  	char			phys[32];
142  	unsigned short		keymap[LM8323_KEYMAP_SIZE];
143  	int			size_x;
144  	int			size_y;
145  	int			debounce_time;
146  	int			active_time;
147  	struct lm8323_pwm	pwm[LM8323_NUM_PWMS];
148  };
149  
150  #define client_to_lm8323(c)	container_of(c, struct lm8323_chip, client)
151  #define dev_to_lm8323(d)	container_of(d, struct lm8323_chip, client->dev)
152  #define cdev_to_pwm(c)		container_of(c, struct lm8323_pwm, cdev)
153  #define work_to_pwm(w)		container_of(w, struct lm8323_pwm, work)
154  
155  #define LM8323_MAX_DATA 8
156  
157  /*
158   * To write, we just access the chip's address in write mode, and dump the
159   * command and data out on the bus.  The command byte and data are taken as
160   * sequential u8s out of varargs, to a maximum of LM8323_MAX_DATA.
161   */
lm8323_write(struct lm8323_chip * lm,int len,...)162  static int lm8323_write(struct lm8323_chip *lm, int len, ...)
163  {
164  	int ret, i;
165  	va_list ap;
166  	u8 data[LM8323_MAX_DATA];
167  
168  	va_start(ap, len);
169  
170  	if (unlikely(len > LM8323_MAX_DATA)) {
171  		dev_err(&lm->client->dev, "tried to send %d bytes\n", len);
172  		va_end(ap);
173  		return 0;
174  	}
175  
176  	for (i = 0; i < len; i++)
177  		data[i] = va_arg(ap, int);
178  
179  	va_end(ap);
180  
181  	/*
182  	 * If the host is asleep while we send the data, we can get a NACK
183  	 * back while it wakes up, so try again, once.
184  	 */
185  	ret = i2c_master_send(lm->client, data, len);
186  	if (unlikely(ret == -EREMOTEIO))
187  		ret = i2c_master_send(lm->client, data, len);
188  	if (unlikely(ret != len))
189  		dev_err(&lm->client->dev, "sent %d bytes of %d total\n",
190  			len, ret);
191  
192  	return ret;
193  }
194  
195  /*
196   * To read, we first send the command byte to the chip and end the transaction,
197   * then access the chip in read mode, at which point it will send the data.
198   */
lm8323_read(struct lm8323_chip * lm,u8 cmd,u8 * buf,int len)199  static int lm8323_read(struct lm8323_chip *lm, u8 cmd, u8 *buf, int len)
200  {
201  	int ret;
202  
203  	/*
204  	 * If the host is asleep while we send the byte, we can get a NACK
205  	 * back while it wakes up, so try again, once.
206  	 */
207  	ret = i2c_master_send(lm->client, &cmd, 1);
208  	if (unlikely(ret == -EREMOTEIO))
209  		ret = i2c_master_send(lm->client, &cmd, 1);
210  	if (unlikely(ret != 1)) {
211  		dev_err(&lm->client->dev, "sending read cmd 0x%02x failed\n",
212  			cmd);
213  		return 0;
214  	}
215  
216  	ret = i2c_master_recv(lm->client, buf, len);
217  	if (unlikely(ret != len))
218  		dev_err(&lm->client->dev, "wanted %d bytes, got %d\n",
219  			len, ret);
220  
221  	return ret;
222  }
223  
224  /*
225   * Set the chip active time (idle time before it enters halt).
226   */
lm8323_set_active_time(struct lm8323_chip * lm,int time)227  static void lm8323_set_active_time(struct lm8323_chip *lm, int time)
228  {
229  	lm8323_write(lm, 2, LM8323_CMD_SET_ACTIVE, time >> 2);
230  }
231  
232  /*
233   * The signals are AT-style: the low 7 bits are the keycode, and the top
234   * bit indicates the state (1 for down, 0 for up).
235   */
lm8323_whichkey(u8 event)236  static inline u8 lm8323_whichkey(u8 event)
237  {
238  	return event & 0x7f;
239  }
240  
lm8323_ispress(u8 event)241  static inline int lm8323_ispress(u8 event)
242  {
243  	return (event & 0x80) ? 1 : 0;
244  }
245  
process_keys(struct lm8323_chip * lm)246  static void process_keys(struct lm8323_chip *lm)
247  {
248  	u8 event;
249  	u8 key_fifo[LM8323_FIFO_LEN + 1];
250  	int old_keys_down = lm->keys_down;
251  	int ret;
252  	int i = 0;
253  
254  	/*
255  	 * Read all key events from the FIFO at once. Next READ_FIFO clears the
256  	 * FIFO even if we didn't read all events previously.
257  	 */
258  	ret = lm8323_read(lm, LM8323_CMD_READ_FIFO, key_fifo, LM8323_FIFO_LEN);
259  
260  	if (ret < 0) {
261  		dev_err(&lm->client->dev, "Failed reading fifo \n");
262  		return;
263  	}
264  	key_fifo[ret] = 0;
265  
266  	while ((event = key_fifo[i++])) {
267  		u8 key = lm8323_whichkey(event);
268  		int isdown = lm8323_ispress(event);
269  		unsigned short keycode = lm->keymap[key];
270  
271  		dev_vdbg(&lm->client->dev, "key 0x%02x %s\n",
272  			 key, isdown ? "down" : "up");
273  
274  		if (lm->kp_enabled) {
275  			input_event(lm->idev, EV_MSC, MSC_SCAN, key);
276  			input_report_key(lm->idev, keycode, isdown);
277  			input_sync(lm->idev);
278  		}
279  
280  		if (isdown)
281  			lm->keys_down++;
282  		else
283  			lm->keys_down--;
284  	}
285  
286  	/*
287  	 * Errata: We need to ensure that the chip never enters halt mode
288  	 * during a keypress, so set active time to 0.  When it's released,
289  	 * we can enter halt again, so set the active time back to normal.
290  	 */
291  	if (!old_keys_down && lm->keys_down)
292  		lm8323_set_active_time(lm, 0);
293  	if (old_keys_down && !lm->keys_down)
294  		lm8323_set_active_time(lm, lm->active_time);
295  }
296  
lm8323_process_error(struct lm8323_chip * lm)297  static void lm8323_process_error(struct lm8323_chip *lm)
298  {
299  	u8 error;
300  
301  	if (lm8323_read(lm, LM8323_CMD_READ_ERR, &error, 1) == 1) {
302  		if (error & ERR_FIFOOVER)
303  			dev_vdbg(&lm->client->dev, "fifo overflow!\n");
304  		if (error & ERR_KEYOVR)
305  			dev_vdbg(&lm->client->dev,
306  					"more than two keys pressed\n");
307  		if (error & ERR_CMDUNK)
308  			dev_vdbg(&lm->client->dev,
309  					"unknown command submitted\n");
310  		if (error & ERR_BADPAR)
311  			dev_vdbg(&lm->client->dev, "bad command parameter\n");
312  	}
313  }
314  
lm8323_reset(struct lm8323_chip * lm)315  static void lm8323_reset(struct lm8323_chip *lm)
316  {
317  	/* The docs say we must pass 0xAA as the data byte. */
318  	lm8323_write(lm, 2, LM8323_CMD_RESET, 0xAA);
319  }
320  
lm8323_configure(struct lm8323_chip * lm)321  static int lm8323_configure(struct lm8323_chip *lm)
322  {
323  	int keysize = (lm->size_x << 4) | lm->size_y;
324  	int clock = (CLK_SLOWCLKEN | CLK_RCPWM_EXTERNAL);
325  	int debounce = lm->debounce_time >> 2;
326  	int active = lm->active_time >> 2;
327  
328  	/*
329  	 * Active time must be greater than the debounce time: if it's
330  	 * a close-run thing, give ourselves a 12ms buffer.
331  	 */
332  	if (debounce >= active)
333  		active = debounce + 3;
334  
335  	lm8323_write(lm, 2, LM8323_CMD_WRITE_CFG, 0);
336  	lm8323_write(lm, 2, LM8323_CMD_WRITE_CLOCK, clock);
337  	lm8323_write(lm, 2, LM8323_CMD_SET_KEY_SIZE, keysize);
338  	lm8323_set_active_time(lm, lm->active_time);
339  	lm8323_write(lm, 2, LM8323_CMD_SET_DEBOUNCE, debounce);
340  	lm8323_write(lm, 3, LM8323_CMD_WRITE_PORT_STATE, 0xff, 0xff);
341  	lm8323_write(lm, 3, LM8323_CMD_WRITE_PORT_SEL, 0, 0);
342  
343  	/*
344  	 * Not much we can do about errors at this point, so just hope
345  	 * for the best.
346  	 */
347  
348  	return 0;
349  }
350  
pwm_done(struct lm8323_pwm * pwm)351  static void pwm_done(struct lm8323_pwm *pwm)
352  {
353  	mutex_lock(&pwm->lock);
354  	pwm->running = false;
355  	if (pwm->desired_brightness != pwm->brightness)
356  		schedule_work(&pwm->work);
357  	mutex_unlock(&pwm->lock);
358  }
359  
360  /*
361   * Bottom half: handle the interrupt by posting key events, or dealing with
362   * errors appropriately.
363   */
lm8323_irq(int irq,void * _lm)364  static irqreturn_t lm8323_irq(int irq, void *_lm)
365  {
366  	struct lm8323_chip *lm = _lm;
367  	u8 ints;
368  	int i;
369  
370  	mutex_lock(&lm->lock);
371  
372  	while ((lm8323_read(lm, LM8323_CMD_READ_INT, &ints, 1) == 1) && ints) {
373  		if (likely(ints & INT_KEYPAD))
374  			process_keys(lm);
375  		if (ints & INT_ROTATOR) {
376  			/* We don't currently support the rotator. */
377  			dev_vdbg(&lm->client->dev, "rotator fired\n");
378  		}
379  		if (ints & INT_ERROR) {
380  			dev_vdbg(&lm->client->dev, "error!\n");
381  			lm8323_process_error(lm);
382  		}
383  		if (ints & INT_NOINIT) {
384  			dev_err(&lm->client->dev, "chip lost config; "
385  						  "reinitialising\n");
386  			lm8323_configure(lm);
387  		}
388  		for (i = 0; i < LM8323_NUM_PWMS; i++) {
389  			if (ints & (INT_PWM1 << i)) {
390  				dev_vdbg(&lm->client->dev,
391  					 "pwm%d engine completed\n", i);
392  				pwm_done(&lm->pwm[i]);
393  			}
394  		}
395  	}
396  
397  	mutex_unlock(&lm->lock);
398  
399  	return IRQ_HANDLED;
400  }
401  
402  /*
403   * Read the chip ID.
404   */
lm8323_read_id(struct lm8323_chip * lm,u8 * buf)405  static int lm8323_read_id(struct lm8323_chip *lm, u8 *buf)
406  {
407  	int bytes;
408  
409  	bytes = lm8323_read(lm, LM8323_CMD_READ_ID, buf, 2);
410  	if (unlikely(bytes != 2))
411  		return -EIO;
412  
413  	return 0;
414  }
415  
lm8323_write_pwm_one(struct lm8323_pwm * pwm,int pos,u16 cmd)416  static void lm8323_write_pwm_one(struct lm8323_pwm *pwm, int pos, u16 cmd)
417  {
418  	lm8323_write(pwm->chip, 4, LM8323_CMD_PWM_WRITE, (pos << 2) | pwm->id,
419  		     (cmd & 0xff00) >> 8, cmd & 0x00ff);
420  }
421  
422  /*
423   * Write a script into a given PWM engine, concluding with PWM_END.
424   * If 'kill' is nonzero, the engine will be shut down at the end
425   * of the script, producing a zero output. Otherwise the engine
426   * will be kept running at the final PWM level indefinitely.
427   */
lm8323_write_pwm(struct lm8323_pwm * pwm,int kill,int len,const u16 * cmds)428  static void lm8323_write_pwm(struct lm8323_pwm *pwm, int kill,
429  			     int len, const u16 *cmds)
430  {
431  	int i;
432  
433  	for (i = 0; i < len; i++)
434  		lm8323_write_pwm_one(pwm, i, cmds[i]);
435  
436  	lm8323_write_pwm_one(pwm, i++, PWM_END(kill));
437  	lm8323_write(pwm->chip, 2, LM8323_CMD_START_PWM, pwm->id);
438  	pwm->running = true;
439  }
440  
lm8323_pwm_work(struct work_struct * work)441  static void lm8323_pwm_work(struct work_struct *work)
442  {
443  	struct lm8323_pwm *pwm = work_to_pwm(work);
444  	int div512, perstep, steps, hz, up, kill;
445  	u16 pwm_cmds[3];
446  	int num_cmds = 0;
447  
448  	mutex_lock(&pwm->lock);
449  
450  	/*
451  	 * Do nothing if we're already at the requested level,
452  	 * or previous setting is not yet complete. In the latter
453  	 * case we will be called again when the previous PWM script
454  	 * finishes.
455  	 */
456  	if (pwm->running || pwm->desired_brightness == pwm->brightness)
457  		goto out;
458  
459  	kill = (pwm->desired_brightness == 0);
460  	up = (pwm->desired_brightness > pwm->brightness);
461  	steps = abs(pwm->desired_brightness - pwm->brightness);
462  
463  	/*
464  	 * Convert time (in ms) into a divisor (512 or 16 on a refclk of
465  	 * 32768Hz), and number of ticks per step.
466  	 */
467  	if ((pwm->fade_time / steps) > (32768 / 512)) {
468  		div512 = 1;
469  		hz = 32768 / 512;
470  	} else {
471  		div512 = 0;
472  		hz = 32768 / 16;
473  	}
474  
475  	perstep = (hz * pwm->fade_time) / (steps * 1000);
476  
477  	if (perstep == 0)
478  		perstep = 1;
479  	else if (perstep > 63)
480  		perstep = 63;
481  
482  	while (steps) {
483  		int s;
484  
485  		s = min(126, steps);
486  		pwm_cmds[num_cmds++] = PWM_RAMP(div512, perstep, s, up);
487  		steps -= s;
488  	}
489  
490  	lm8323_write_pwm(pwm, kill, num_cmds, pwm_cmds);
491  	pwm->brightness = pwm->desired_brightness;
492  
493   out:
494  	mutex_unlock(&pwm->lock);
495  }
496  
lm8323_pwm_set_brightness(struct led_classdev * led_cdev,enum led_brightness brightness)497  static void lm8323_pwm_set_brightness(struct led_classdev *led_cdev,
498  				      enum led_brightness brightness)
499  {
500  	struct lm8323_pwm *pwm = cdev_to_pwm(led_cdev);
501  	struct lm8323_chip *lm = pwm->chip;
502  
503  	mutex_lock(&pwm->lock);
504  	pwm->desired_brightness = brightness;
505  	mutex_unlock(&pwm->lock);
506  
507  	if (in_interrupt()) {
508  		schedule_work(&pwm->work);
509  	} else {
510  		/*
511  		 * Schedule PWM work as usual unless we are going into suspend
512  		 */
513  		mutex_lock(&lm->lock);
514  		if (likely(!lm->pm_suspend))
515  			schedule_work(&pwm->work);
516  		else
517  			lm8323_pwm_work(&pwm->work);
518  		mutex_unlock(&lm->lock);
519  	}
520  }
521  
lm8323_pwm_show_time(struct device * dev,struct device_attribute * attr,char * buf)522  static ssize_t lm8323_pwm_show_time(struct device *dev,
523  		struct device_attribute *attr, char *buf)
524  {
525  	struct led_classdev *led_cdev = dev_get_drvdata(dev);
526  	struct lm8323_pwm *pwm = cdev_to_pwm(led_cdev);
527  
528  	return sprintf(buf, "%d\n", pwm->fade_time);
529  }
530  
lm8323_pwm_store_time(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)531  static ssize_t lm8323_pwm_store_time(struct device *dev,
532  		struct device_attribute *attr, const char *buf, size_t len)
533  {
534  	struct led_classdev *led_cdev = dev_get_drvdata(dev);
535  	struct lm8323_pwm *pwm = cdev_to_pwm(led_cdev);
536  	int ret, time;
537  
538  	ret = kstrtoint(buf, 10, &time);
539  	/* Numbers only, please. */
540  	if (ret)
541  		return ret;
542  
543  	pwm->fade_time = time;
544  
545  	return strlen(buf);
546  }
547  static DEVICE_ATTR(time, 0644, lm8323_pwm_show_time, lm8323_pwm_store_time);
548  
549  static struct attribute *lm8323_pwm_attrs[] = {
550  	&dev_attr_time.attr,
551  	NULL
552  };
553  ATTRIBUTE_GROUPS(lm8323_pwm);
554  
init_pwm(struct lm8323_chip * lm,int id,struct device * dev,const char * name)555  static int init_pwm(struct lm8323_chip *lm, int id, struct device *dev,
556  		    const char *name)
557  {
558  	struct lm8323_pwm *pwm;
559  	int err;
560  
561  	BUG_ON(id > 3);
562  
563  	pwm = &lm->pwm[id - 1];
564  
565  	pwm->id = id;
566  	pwm->fade_time = 0;
567  	pwm->brightness = 0;
568  	pwm->desired_brightness = 0;
569  	pwm->running = false;
570  	pwm->enabled = false;
571  	INIT_WORK(&pwm->work, lm8323_pwm_work);
572  	mutex_init(&pwm->lock);
573  	pwm->chip = lm;
574  
575  	if (name) {
576  		pwm->cdev.name = name;
577  		pwm->cdev.brightness_set = lm8323_pwm_set_brightness;
578  		pwm->cdev.groups = lm8323_pwm_groups;
579  
580  		err = devm_led_classdev_register(dev, &pwm->cdev);
581  		if (err) {
582  			dev_err(dev, "couldn't register PWM %d: %d\n", id, err);
583  			return err;
584  		}
585  		pwm->enabled = true;
586  	}
587  
588  	return 0;
589  }
590  
lm8323_show_disable(struct device * dev,struct device_attribute * attr,char * buf)591  static ssize_t lm8323_show_disable(struct device *dev,
592  				   struct device_attribute *attr, char *buf)
593  {
594  	struct lm8323_chip *lm = dev_get_drvdata(dev);
595  
596  	return sprintf(buf, "%u\n", !lm->kp_enabled);
597  }
598  
lm8323_set_disable(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)599  static ssize_t lm8323_set_disable(struct device *dev,
600  				  struct device_attribute *attr,
601  				  const char *buf, size_t count)
602  {
603  	struct lm8323_chip *lm = dev_get_drvdata(dev);
604  	int ret;
605  	unsigned int i;
606  
607  	ret = kstrtouint(buf, 10, &i);
608  	if (ret)
609  		return ret;
610  
611  	mutex_lock(&lm->lock);
612  	lm->kp_enabled = !i;
613  	mutex_unlock(&lm->lock);
614  
615  	return count;
616  }
617  static DEVICE_ATTR(disable_kp, 0644, lm8323_show_disable, lm8323_set_disable);
618  
619  static struct attribute *lm8323_attrs[] = {
620  	&dev_attr_disable_kp.attr,
621  	NULL,
622  };
623  ATTRIBUTE_GROUPS(lm8323);
624  
lm8323_probe(struct i2c_client * client)625  static int lm8323_probe(struct i2c_client *client)
626  {
627  	struct lm8323_platform_data *pdata = dev_get_platdata(&client->dev);
628  	struct input_dev *idev;
629  	struct lm8323_chip *lm;
630  	int pwm;
631  	int i, err;
632  	unsigned long tmo;
633  	u8 data[2];
634  
635  	if (!pdata || !pdata->size_x || !pdata->size_y) {
636  		dev_err(&client->dev, "missing platform_data\n");
637  		return -EINVAL;
638  	}
639  
640  	if (pdata->size_x > 8) {
641  		dev_err(&client->dev, "invalid x size %d specified\n",
642  			pdata->size_x);
643  		return -EINVAL;
644  	}
645  
646  	if (pdata->size_y > 12) {
647  		dev_err(&client->dev, "invalid y size %d specified\n",
648  			pdata->size_y);
649  		return -EINVAL;
650  	}
651  
652  	lm = devm_kzalloc(&client->dev, sizeof(*lm), GFP_KERNEL);
653  	if (!lm)
654  		return -ENOMEM;
655  
656  	idev = devm_input_allocate_device(&client->dev);
657  	if (!idev)
658  		return -ENOMEM;
659  
660  	lm->client = client;
661  	lm->idev = idev;
662  	mutex_init(&lm->lock);
663  
664  	lm->size_x = pdata->size_x;
665  	lm->size_y = pdata->size_y;
666  	dev_vdbg(&client->dev, "Keypad size: %d x %d\n",
667  		 lm->size_x, lm->size_y);
668  
669  	lm->debounce_time = pdata->debounce_time;
670  	lm->active_time = pdata->active_time;
671  
672  	lm8323_reset(lm);
673  
674  	/*
675  	 * Nothing's set up to service the IRQ yet, so just spin for max.
676  	 * 100ms until we can configure.
677  	 */
678  	tmo = jiffies + msecs_to_jiffies(100);
679  	while (lm8323_read(lm, LM8323_CMD_READ_INT, data, 1) == 1) {
680  		if (data[0] & INT_NOINIT)
681  			break;
682  
683  		if (time_after(jiffies, tmo)) {
684  			dev_err(&client->dev,
685  				"timeout waiting for initialisation\n");
686  			break;
687  		}
688  
689  		msleep(1);
690  	}
691  
692  	lm8323_configure(lm);
693  
694  	/* If a true probe check the device */
695  	if (lm8323_read_id(lm, data) != 0) {
696  		dev_err(&client->dev, "device not found\n");
697  		return -ENODEV;
698  	}
699  
700  	for (pwm = 0; pwm < LM8323_NUM_PWMS; pwm++) {
701  		err = init_pwm(lm, pwm + 1, &client->dev,
702  			       pdata->pwm_names[pwm]);
703  		if (err)
704  			return err;
705  	}
706  
707  	lm->kp_enabled = true;
708  
709  	idev->name = pdata->name ? : "LM8323 keypad";
710  	snprintf(lm->phys, sizeof(lm->phys),
711  		 "%s/input-kp", dev_name(&client->dev));
712  	idev->phys = lm->phys;
713  
714  	idev->evbit[0] = BIT(EV_KEY) | BIT(EV_MSC);
715  	__set_bit(MSC_SCAN, idev->mscbit);
716  	for (i = 0; i < LM8323_KEYMAP_SIZE; i++) {
717  		__set_bit(pdata->keymap[i], idev->keybit);
718  		lm->keymap[i] = pdata->keymap[i];
719  	}
720  	__clear_bit(KEY_RESERVED, idev->keybit);
721  
722  	if (pdata->repeat)
723  		__set_bit(EV_REP, idev->evbit);
724  
725  	err = input_register_device(idev);
726  	if (err) {
727  		dev_dbg(&client->dev, "error registering input device\n");
728  		return err;
729  	}
730  
731  	err = devm_request_threaded_irq(&client->dev, client->irq,
732  					NULL, lm8323_irq,
733  					IRQF_TRIGGER_LOW | IRQF_ONESHOT,
734  					"lm8323", lm);
735  	if (err) {
736  		dev_err(&client->dev, "could not get IRQ %d\n", client->irq);
737  		return err;
738  	}
739  
740  	i2c_set_clientdata(client, lm);
741  
742  	device_init_wakeup(&client->dev, 1);
743  	enable_irq_wake(client->irq);
744  
745  	return 0;
746  }
747  
748  /*
749   * We don't need to explicitly suspend the chip, as it already switches off
750   * when there's no activity.
751   */
lm8323_suspend(struct device * dev)752  static int lm8323_suspend(struct device *dev)
753  {
754  	struct i2c_client *client = to_i2c_client(dev);
755  	struct lm8323_chip *lm = i2c_get_clientdata(client);
756  	int i;
757  
758  	irq_set_irq_wake(client->irq, 0);
759  	disable_irq(client->irq);
760  
761  	mutex_lock(&lm->lock);
762  	lm->pm_suspend = true;
763  	mutex_unlock(&lm->lock);
764  
765  	for (i = 0; i < 3; i++)
766  		if (lm->pwm[i].enabled)
767  			led_classdev_suspend(&lm->pwm[i].cdev);
768  
769  	return 0;
770  }
771  
lm8323_resume(struct device * dev)772  static int lm8323_resume(struct device *dev)
773  {
774  	struct i2c_client *client = to_i2c_client(dev);
775  	struct lm8323_chip *lm = i2c_get_clientdata(client);
776  	int i;
777  
778  	mutex_lock(&lm->lock);
779  	lm->pm_suspend = false;
780  	mutex_unlock(&lm->lock);
781  
782  	for (i = 0; i < 3; i++)
783  		if (lm->pwm[i].enabled)
784  			led_classdev_resume(&lm->pwm[i].cdev);
785  
786  	enable_irq(client->irq);
787  	irq_set_irq_wake(client->irq, 1);
788  
789  	return 0;
790  }
791  
792  static DEFINE_SIMPLE_DEV_PM_OPS(lm8323_pm_ops, lm8323_suspend, lm8323_resume);
793  
794  static const struct i2c_device_id lm8323_id[] = {
795  	{ "lm8323", 0 },
796  	{ }
797  };
798  
799  static struct i2c_driver lm8323_i2c_driver = {
800  	.driver = {
801  		.name		= "lm8323",
802  		.pm		= pm_sleep_ptr(&lm8323_pm_ops),
803  		.dev_groups	= lm8323_groups,
804  	},
805  	.probe		= lm8323_probe,
806  	.id_table	= lm8323_id,
807  };
808  MODULE_DEVICE_TABLE(i2c, lm8323_id);
809  
810  module_i2c_driver(lm8323_i2c_driver);
811  
812  MODULE_AUTHOR("Timo O. Karjalainen <timo.o.karjalainen@nokia.com>");
813  MODULE_AUTHOR("Daniel Stone");
814  MODULE_AUTHOR("Felipe Balbi <felipe.balbi@nokia.com>");
815  MODULE_DESCRIPTION("LM8323 keypad driver");
816  MODULE_LICENSE("GPL");
817  
818