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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/pm.h>
34#include <linux/i2c/lm8323.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
131struct 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
145struct 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 */
174static 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 */
211static 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 */
239static 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 */
248static inline u8 lm8323_whichkey(u8 event)
249{
250 return event & 0x7f;
251}
252
253static inline int lm8323_ispress(u8 event)
254{
255 return (event & 0x80) ? 1 : 0;
256}
257
258static 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
309static 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
327static 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
333static 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
363static 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 */
376static 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 & (1 << (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 */
417static 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
428static 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 */
440static 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
453static 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
509static 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
534static 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
543static 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;
549 unsigned long time;
550
551 ret = strict_strtoul(buf, 10, &time);
552 /* Numbers only, please. */
553 if (ret)
554 return -EINVAL;
555
556 pwm->fade_time = time;
557
558 return strlen(buf);
559}
560static DEVICE_ATTR(time, 0644, lm8323_pwm_show_time, lm8323_pwm_store_time);
561
562static int init_pwm(struct lm8323_chip *lm, int id, struct device *dev,
563 const char *name)
564{
565 struct lm8323_pwm *pwm;
566
567 BUG_ON(id > 3);
568
569 pwm = &lm->pwm[id - 1];
570
571 pwm->id = id;
572 pwm->fade_time = 0;
573 pwm->brightness = 0;
574 pwm->desired_brightness = 0;
575 pwm->running = false;
576 pwm->enabled = false;
577 INIT_WORK(&pwm->work, lm8323_pwm_work);
578 mutex_init(&pwm->lock);
579 pwm->chip = lm;
580
581 if (name) {
582 pwm->cdev.name = name;
583 pwm->cdev.brightness_set = lm8323_pwm_set_brightness;
584 if (led_classdev_register(dev, &pwm->cdev) < 0) {
585 dev_err(dev, "couldn't register PWM %d\n", id);
586 return -1;
587 }
588 if (device_create_file(pwm->cdev.dev,
589 &dev_attr_time) < 0) {
590 dev_err(dev, "couldn't register time attribute\n");
591 led_classdev_unregister(&pwm->cdev);
592 return -1;
593 }
594 pwm->enabled = true;
595 }
596
597 return 0;
598}
599
600static struct i2c_driver lm8323_i2c_driver;
601
602static 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
610static 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 long i;
617
618 ret = strict_strtoul(buf, 10, &i);
619
620 mutex_lock(&lm->lock);
621 lm->kp_enabled = !i;
622 mutex_unlock(&lm->lock);
623
624 return count;
625}
626static DEVICE_ATTR(disable_kp, 0644, lm8323_show_disable, lm8323_set_disable);
627
628static int __devinit lm8323_probe(struct i2c_client *client,
629 const struct i2c_device_id *id)
630{
631 struct lm8323_platform_data *pdata = client->dev.platform_data;
632 struct input_dev *idev;
633 struct lm8323_chip *lm;
634 int pwm;
635 int i, err;
636 unsigned long tmo;
637 u8 data[2];
638
639 if (!pdata || !pdata->size_x || !pdata->size_y) {
640 dev_err(&client->dev, "missing platform_data\n");
641 return -EINVAL;
642 }
643
644 if (pdata->size_x > 8) {
645 dev_err(&client->dev, "invalid x size %d specified\n",
646 pdata->size_x);
647 return -EINVAL;
648 }
649
650 if (pdata->size_y > 12) {
651 dev_err(&client->dev, "invalid y size %d specified\n",
652 pdata->size_y);
653 return -EINVAL;
654 }
655
656 lm = kzalloc(sizeof *lm, GFP_KERNEL);
657 idev = input_allocate_device();
658 if (!lm || !idev) {
659 err = -ENOMEM;
660 goto fail1;
661 }
662
663 lm->client = client;
664 lm->idev = idev;
665 mutex_init(&lm->lock);
666
667 lm->size_x = pdata->size_x;
668 lm->size_y = pdata->size_y;
669 dev_vdbg(&client->dev, "Keypad size: %d x %d\n",
670 lm->size_x, lm->size_y);
671
672 lm->debounce_time = pdata->debounce_time;
673 lm->active_time = pdata->active_time;
674
675 lm8323_reset(lm);
676
677 /* Nothing's set up to service the IRQ yet, so just spin for max.
678 * 100ms until we can configure. */
679 tmo = jiffies + msecs_to_jiffies(100);
680 while (lm8323_read(lm, LM8323_CMD_READ_INT, data, 1) == 1) {
681 if (data[0] & INT_NOINIT)
682 break;
683
684 if (time_after(jiffies, tmo)) {
685 dev_err(&client->dev,
686 "timeout waiting for initialisation\n");
687 break;
688 }
689
690 msleep(1);
691 }
692
693 lm8323_configure(lm);
694
695 /* If a true probe check the device */
696 if (lm8323_read_id(lm, data) != 0) {
697 dev_err(&client->dev, "device not found\n");
698 err = -ENODEV;
699 goto fail1;
700 }
701
702 for (pwm = 0; pwm < LM8323_NUM_PWMS; pwm++) {
703 err = init_pwm(lm, pwm + 1, &client->dev,
704 pdata->pwm_names[pwm]);
705 if (err < 0)
706 goto fail2;
707 }
708
709 lm->kp_enabled = true;
710 err = device_create_file(&client->dev, &dev_attr_disable_kp);
711 if (err < 0)
712 goto fail2;
713
714 idev->name = pdata->name ? : "LM8323 keypad";
715 snprintf(lm->phys, sizeof(lm->phys),
716 "%s/input-kp", dev_name(&client->dev));
717 idev->phys = lm->phys;
718
719 idev->evbit[0] = BIT(EV_KEY) | BIT(EV_MSC);
720 __set_bit(MSC_SCAN, idev->mscbit);
721 for (i = 0; i < LM8323_KEYMAP_SIZE; i++) {
722 __set_bit(pdata->keymap[i], idev->keybit);
723 lm->keymap[i] = pdata->keymap[i];
724 }
725 __clear_bit(KEY_RESERVED, idev->keybit);
726
727 if (pdata->repeat)
728 __set_bit(EV_REP, idev->evbit);
729
730 err = input_register_device(idev);
731 if (err) {
732 dev_dbg(&client->dev, "error registering input device\n");
733 goto fail3;
734 }
735
736 err = request_threaded_irq(client->irq, NULL, lm8323_irq,
737 IRQF_TRIGGER_LOW|IRQF_ONESHOT, "lm8323", lm);
738 if (err) {
739 dev_err(&client->dev, "could not get IRQ %d\n", client->irq);
740 goto fail4;
741 }
742
743 i2c_set_clientdata(client, lm);
744
745 device_init_wakeup(&client->dev, 1);
746 enable_irq_wake(client->irq);
747
748 return 0;
749
750fail4:
751 input_unregister_device(idev);
752 idev = NULL;
753fail3:
754 device_remove_file(&client->dev, &dev_attr_disable_kp);
755fail2:
756 while (--pwm >= 0)
757 if (lm->pwm[pwm].enabled) {
758 device_remove_file(lm->pwm[pwm].cdev.dev,
759 &dev_attr_time);
760 led_classdev_unregister(&lm->pwm[pwm].cdev);
761 }
762fail1:
763 input_free_device(idev);
764 kfree(lm);
765 return err;
766}
767
768static int __devexit lm8323_remove(struct i2c_client *client)
769{
770 struct lm8323_chip *lm = i2c_get_clientdata(client);
771 int i;
772
773 disable_irq_wake(client->irq);
774 free_irq(client->irq, lm);
775
776 input_unregister_device(lm->idev);
777
778 device_remove_file(&lm->client->dev, &dev_attr_disable_kp);
779
780 for (i = 0; i < 3; i++)
781 if (lm->pwm[i].enabled) {
782 device_remove_file(lm->pwm[i].cdev.dev, &dev_attr_time);
783 led_classdev_unregister(&lm->pwm[i].cdev);
784 }
785
786 kfree(lm);
787
788 return 0;
789}
790
791#ifdef CONFIG_PM
792/*
793 * We don't need to explicitly suspend the chip, as it already switches off
794 * when there's no activity.
795 */
796static int lm8323_suspend(struct device *dev)
797{
798 struct i2c_client *client = to_i2c_client(dev);
799 struct lm8323_chip *lm = i2c_get_clientdata(client);
800 int i;
801
802 irq_set_irq_wake(client->irq, 0);
803 disable_irq(client->irq);
804
805 mutex_lock(&lm->lock);
806 lm->pm_suspend = true;
807 mutex_unlock(&lm->lock);
808
809 for (i = 0; i < 3; i++)
810 if (lm->pwm[i].enabled)
811 led_classdev_suspend(&lm->pwm[i].cdev);
812
813 return 0;
814}
815
816static int lm8323_resume(struct device *dev)
817{
818 struct i2c_client *client = to_i2c_client(dev);
819 struct lm8323_chip *lm = i2c_get_clientdata(client);
820 int i;
821
822 mutex_lock(&lm->lock);
823 lm->pm_suspend = false;
824 mutex_unlock(&lm->lock);
825
826 for (i = 0; i < 3; i++)
827 if (lm->pwm[i].enabled)
828 led_classdev_resume(&lm->pwm[i].cdev);
829
830 enable_irq(client->irq);
831 irq_set_irq_wake(client->irq, 1);
832
833 return 0;
834}
835#endif
836
837static SIMPLE_DEV_PM_OPS(lm8323_pm_ops, lm8323_suspend, lm8323_resume);
838
839static const struct i2c_device_id lm8323_id[] = {
840 { "lm8323", 0 },
841 { }
842};
843
844static struct i2c_driver lm8323_i2c_driver = {
845 .driver = {
846 .name = "lm8323",
847 .pm = &lm8323_pm_ops,
848 },
849 .probe = lm8323_probe,
850 .remove = __devexit_p(lm8323_remove),
851 .id_table = lm8323_id,
852};
853MODULE_DEVICE_TABLE(i2c, lm8323_id);
854
855static int __init lm8323_init(void)
856{
857 return i2c_add_driver(&lm8323_i2c_driver);
858}
859module_init(lm8323_init);
860
861static void __exit lm8323_exit(void)
862{
863 i2c_del_driver(&lm8323_i2c_driver);
864}
865module_exit(lm8323_exit);
866
867MODULE_AUTHOR("Timo O. Karjalainen <timo.o.karjalainen@nokia.com>");
868MODULE_AUTHOR("Daniel Stone");
869MODULE_AUTHOR("Felipe Balbi <felipe.balbi@nokia.com>");
870MODULE_DESCRIPTION("LM8323 keypad driver");
871MODULE_LICENSE("GPL");
872
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
119struct 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
133struct 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 */
162static 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 */
199static 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 */
227static 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 */
236static inline u8 lm8323_whichkey(u8 event)
237{
238 return event & 0x7f;
239}
240
241static inline int lm8323_ispress(u8 event)
242{
243 return (event & 0x80) ? 1 : 0;
244}
245
246static 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
297static 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
315static 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
321static 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
351static 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 */
364static 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 */
405static 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
416static 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 */
428static 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
441static 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
497static 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
522static 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
531static 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}
547static DEVICE_ATTR(time, 0644, lm8323_pwm_show_time, lm8323_pwm_store_time);
548
549static struct attribute *lm8323_pwm_attrs[] = {
550 &dev_attr_time.attr,
551 NULL
552};
553ATTRIBUTE_GROUPS(lm8323_pwm);
554
555static int init_pwm(struct lm8323_chip *lm, int id, struct device *dev,
556 const char *name)
557{
558 struct lm8323_pwm *pwm;
559
560 BUG_ON(id > 3);
561
562 pwm = &lm->pwm[id - 1];
563
564 pwm->id = id;
565 pwm->fade_time = 0;
566 pwm->brightness = 0;
567 pwm->desired_brightness = 0;
568 pwm->running = false;
569 pwm->enabled = false;
570 INIT_WORK(&pwm->work, lm8323_pwm_work);
571 mutex_init(&pwm->lock);
572 pwm->chip = lm;
573
574 if (name) {
575 pwm->cdev.name = name;
576 pwm->cdev.brightness_set = lm8323_pwm_set_brightness;
577 pwm->cdev.groups = lm8323_pwm_groups;
578 if (led_classdev_register(dev, &pwm->cdev) < 0) {
579 dev_err(dev, "couldn't register PWM %d\n", id);
580 return -1;
581 }
582 pwm->enabled = true;
583 }
584
585 return 0;
586}
587
588static struct i2c_driver lm8323_i2c_driver;
589
590static ssize_t lm8323_show_disable(struct device *dev,
591 struct device_attribute *attr, char *buf)
592{
593 struct lm8323_chip *lm = dev_get_drvdata(dev);
594
595 return sprintf(buf, "%u\n", !lm->kp_enabled);
596}
597
598static ssize_t lm8323_set_disable(struct device *dev,
599 struct device_attribute *attr,
600 const char *buf, size_t count)
601{
602 struct lm8323_chip *lm = dev_get_drvdata(dev);
603 int ret;
604 unsigned int i;
605
606 ret = kstrtouint(buf, 10, &i);
607 if (ret)
608 return ret;
609
610 mutex_lock(&lm->lock);
611 lm->kp_enabled = !i;
612 mutex_unlock(&lm->lock);
613
614 return count;
615}
616static DEVICE_ATTR(disable_kp, 0644, lm8323_show_disable, lm8323_set_disable);
617
618static int lm8323_probe(struct i2c_client *client)
619{
620 struct lm8323_platform_data *pdata = dev_get_platdata(&client->dev);
621 struct input_dev *idev;
622 struct lm8323_chip *lm;
623 int pwm;
624 int i, err;
625 unsigned long tmo;
626 u8 data[2];
627
628 if (!pdata || !pdata->size_x || !pdata->size_y) {
629 dev_err(&client->dev, "missing platform_data\n");
630 return -EINVAL;
631 }
632
633 if (pdata->size_x > 8) {
634 dev_err(&client->dev, "invalid x size %d specified\n",
635 pdata->size_x);
636 return -EINVAL;
637 }
638
639 if (pdata->size_y > 12) {
640 dev_err(&client->dev, "invalid y size %d specified\n",
641 pdata->size_y);
642 return -EINVAL;
643 }
644
645 lm = kzalloc(sizeof *lm, GFP_KERNEL);
646 idev = input_allocate_device();
647 if (!lm || !idev) {
648 err = -ENOMEM;
649 goto fail1;
650 }
651
652 lm->client = client;
653 lm->idev = idev;
654 mutex_init(&lm->lock);
655
656 lm->size_x = pdata->size_x;
657 lm->size_y = pdata->size_y;
658 dev_vdbg(&client->dev, "Keypad size: %d x %d\n",
659 lm->size_x, lm->size_y);
660
661 lm->debounce_time = pdata->debounce_time;
662 lm->active_time = pdata->active_time;
663
664 lm8323_reset(lm);
665
666 /* Nothing's set up to service the IRQ yet, so just spin for max.
667 * 100ms until we can configure. */
668 tmo = jiffies + msecs_to_jiffies(100);
669 while (lm8323_read(lm, LM8323_CMD_READ_INT, data, 1) == 1) {
670 if (data[0] & INT_NOINIT)
671 break;
672
673 if (time_after(jiffies, tmo)) {
674 dev_err(&client->dev,
675 "timeout waiting for initialisation\n");
676 break;
677 }
678
679 msleep(1);
680 }
681
682 lm8323_configure(lm);
683
684 /* If a true probe check the device */
685 if (lm8323_read_id(lm, data) != 0) {
686 dev_err(&client->dev, "device not found\n");
687 err = -ENODEV;
688 goto fail1;
689 }
690
691 for (pwm = 0; pwm < LM8323_NUM_PWMS; pwm++) {
692 err = init_pwm(lm, pwm + 1, &client->dev,
693 pdata->pwm_names[pwm]);
694 if (err < 0)
695 goto fail2;
696 }
697
698 lm->kp_enabled = true;
699 err = device_create_file(&client->dev, &dev_attr_disable_kp);
700 if (err < 0)
701 goto fail2;
702
703 idev->name = pdata->name ? : "LM8323 keypad";
704 snprintf(lm->phys, sizeof(lm->phys),
705 "%s/input-kp", dev_name(&client->dev));
706 idev->phys = lm->phys;
707
708 idev->evbit[0] = BIT(EV_KEY) | BIT(EV_MSC);
709 __set_bit(MSC_SCAN, idev->mscbit);
710 for (i = 0; i < LM8323_KEYMAP_SIZE; i++) {
711 __set_bit(pdata->keymap[i], idev->keybit);
712 lm->keymap[i] = pdata->keymap[i];
713 }
714 __clear_bit(KEY_RESERVED, idev->keybit);
715
716 if (pdata->repeat)
717 __set_bit(EV_REP, idev->evbit);
718
719 err = input_register_device(idev);
720 if (err) {
721 dev_dbg(&client->dev, "error registering input device\n");
722 goto fail3;
723 }
724
725 err = request_threaded_irq(client->irq, NULL, lm8323_irq,
726 IRQF_TRIGGER_LOW|IRQF_ONESHOT, "lm8323", lm);
727 if (err) {
728 dev_err(&client->dev, "could not get IRQ %d\n", client->irq);
729 goto fail4;
730 }
731
732 i2c_set_clientdata(client, lm);
733
734 device_init_wakeup(&client->dev, 1);
735 enable_irq_wake(client->irq);
736
737 return 0;
738
739fail4:
740 input_unregister_device(idev);
741 idev = NULL;
742fail3:
743 device_remove_file(&client->dev, &dev_attr_disable_kp);
744fail2:
745 while (--pwm >= 0)
746 if (lm->pwm[pwm].enabled)
747 led_classdev_unregister(&lm->pwm[pwm].cdev);
748fail1:
749 input_free_device(idev);
750 kfree(lm);
751 return err;
752}
753
754static void lm8323_remove(struct i2c_client *client)
755{
756 struct lm8323_chip *lm = i2c_get_clientdata(client);
757 int i;
758
759 disable_irq_wake(client->irq);
760 free_irq(client->irq, lm);
761
762 input_unregister_device(lm->idev);
763
764 device_remove_file(&lm->client->dev, &dev_attr_disable_kp);
765
766 for (i = 0; i < 3; i++)
767 if (lm->pwm[i].enabled)
768 led_classdev_unregister(&lm->pwm[i].cdev);
769
770 kfree(lm);
771}
772
773/*
774 * We don't need to explicitly suspend the chip, as it already switches off
775 * when there's no activity.
776 */
777static int lm8323_suspend(struct device *dev)
778{
779 struct i2c_client *client = to_i2c_client(dev);
780 struct lm8323_chip *lm = i2c_get_clientdata(client);
781 int i;
782
783 irq_set_irq_wake(client->irq, 0);
784 disable_irq(client->irq);
785
786 mutex_lock(&lm->lock);
787 lm->pm_suspend = true;
788 mutex_unlock(&lm->lock);
789
790 for (i = 0; i < 3; i++)
791 if (lm->pwm[i].enabled)
792 led_classdev_suspend(&lm->pwm[i].cdev);
793
794 return 0;
795}
796
797static int lm8323_resume(struct device *dev)
798{
799 struct i2c_client *client = to_i2c_client(dev);
800 struct lm8323_chip *lm = i2c_get_clientdata(client);
801 int i;
802
803 mutex_lock(&lm->lock);
804 lm->pm_suspend = false;
805 mutex_unlock(&lm->lock);
806
807 for (i = 0; i < 3; i++)
808 if (lm->pwm[i].enabled)
809 led_classdev_resume(&lm->pwm[i].cdev);
810
811 enable_irq(client->irq);
812 irq_set_irq_wake(client->irq, 1);
813
814 return 0;
815}
816
817static DEFINE_SIMPLE_DEV_PM_OPS(lm8323_pm_ops, lm8323_suspend, lm8323_resume);
818
819static const struct i2c_device_id lm8323_id[] = {
820 { "lm8323", 0 },
821 { }
822};
823
824static struct i2c_driver lm8323_i2c_driver = {
825 .driver = {
826 .name = "lm8323",
827 .pm = pm_sleep_ptr(&lm8323_pm_ops),
828 },
829 .probe_new = lm8323_probe,
830 .remove = lm8323_remove,
831 .id_table = lm8323_id,
832};
833MODULE_DEVICE_TABLE(i2c, lm8323_id);
834
835module_i2c_driver(lm8323_i2c_driver);
836
837MODULE_AUTHOR("Timo O. Karjalainen <timo.o.karjalainen@nokia.com>");
838MODULE_AUTHOR("Daniel Stone");
839MODULE_AUTHOR("Felipe Balbi <felipe.balbi@nokia.com>");
840MODULE_DESCRIPTION("LM8323 keypad driver");
841MODULE_LICENSE("GPL");
842