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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * leds-tca6507
4 *
5 * The TCA6507 is a programmable LED controller that can drive 7
6 * separate lines either by holding them low, or by pulsing them
7 * with modulated width.
8 * The modulation can be varied in a simple pattern to produce a
9 * blink or double-blink.
10 *
11 * This driver can configure each line either as a 'GPIO' which is
12 * out-only (pull-up resistor required) or as an LED with variable
13 * brightness and hardware-assisted blinking.
14 *
15 * Apart from OFF and ON there are three programmable brightness
16 * levels which can be programmed from 0 to 15 and indicate how many
17 * 500usec intervals in each 8msec that the led is 'on'. The levels
18 * are named MASTER, BANK0 and BANK1.
19 *
20 * There are two different blink rates that can be programmed, each
21 * with separate time for rise, on, fall, off and second-off. Thus if
22 * 3 or more different non-trivial rates are required, software must
23 * be used for the extra rates. The two different blink rates must
24 * align with the two levels BANK0 and BANK1. This driver does not
25 * support double-blink so 'second-off' always matches 'off'.
26 *
27 * Only 16 different times can be programmed in a roughly logarithmic
28 * scale from 64ms to 16320ms. To be precise the possible times are:
29 * 0, 64, 128, 192, 256, 384, 512, 768,
30 * 1024, 1536, 2048, 3072, 4096, 5760, 8128, 16320
31 *
32 * Times that cannot be closely matched with these must be handled in
33 * software. This driver allows 12.5% error in matching.
34 *
35 * This driver does not allow rise/fall rates to be set explicitly.
36 * When trying to match a given 'on' or 'off' period, an appropriate
37 * pair of 'change' and 'hold' times are chosen to get a close match.
38 * If the target delay is even, the 'change' number will be the
39 * smaller; if odd, the 'hold' number will be the smaller.
40
41 * Choosing pairs of delays with 12.5% errors allows us to match
42 * delays in the ranges: 56-72, 112-144, 168-216, 224-27504,
43 * 28560-36720.
44 * 26% of the achievable sums can be matched by multiple pairings.
45 * For example 1536 == 1536+0, 1024+512, or 768+768.
46 * This driver will always choose the pairing with the least
47 * maximum - 768+768 in this case. Other pairings are not available.
48 *
49 * Access to the 3 levels and 2 blinks are on a first-come,
50 * first-served basis. Access can be shared by multiple leds if they
51 * have the same level and either same blink rates, or some don't
52 * blink. When a led changes, it relinquishes access and tries again,
53 * so it might lose access to hardware blink.
54 *
55 * If a blink engine cannot be allocated, software blink is used. If
56 * the desired brightness cannot be allocated, the closest available
57 * non-zero brightness is used. As 'full' is always available, the
58 * worst case would be to have two different blink rates at '1', with
59 * Max at '2', then other leds will have to choose between '2' and
60 * '16'. Hopefully this is not likely.
61 *
62 * Each bank (BANK0 and BANK1) has two usage counts - LEDs using the
63 * brightness and LEDs using the blink. It can only be reprogrammed
64 * when the appropriate counter is zero. The MASTER level has a
65 * single usage count.
66 *
67 * Each LED has programmable 'on' and 'off' time as milliseconds.
68 * With each there is a flag saying if it was explicitly requested or
69 * defaulted. Similarly the banks know if each time was explicit or a
70 * default. Defaults are permitted to be changed freely - they are
71 * not recognised when matching.
72 */
73
74#include <linux/module.h>
75#include <linux/slab.h>
76#include <linux/leds.h>
77#include <linux/err.h>
78#include <linux/i2c.h>
79#include <linux/gpio/driver.h>
80#include <linux/property.h>
81#include <linux/workqueue.h>
82
83/* LED select registers determine the source that drives LED outputs */
84#define TCA6507_LS_LED_OFF 0x0 /* Output HI-Z (off) */
85#define TCA6507_LS_LED_OFF1 0x1 /* Output HI-Z (off) - not used */
86#define TCA6507_LS_LED_PWM0 0x2 /* Output LOW with Bank0 rate */
87#define TCA6507_LS_LED_PWM1 0x3 /* Output LOW with Bank1 rate */
88#define TCA6507_LS_LED_ON 0x4 /* Output LOW (on) */
89#define TCA6507_LS_LED_MIR 0x5 /* Output LOW with Master Intensity */
90#define TCA6507_LS_BLINK0 0x6 /* Blink at Bank0 rate */
91#define TCA6507_LS_BLINK1 0x7 /* Blink at Bank1 rate */
92
93struct tca6507_platform_data {
94 struct led_platform_data leds;
95#ifdef CONFIG_GPIOLIB
96 int gpio_base;
97#endif
98};
99
100#define TCA6507_MAKE_GPIO 1
101
102enum {
103 BANK0,
104 BANK1,
105 MASTER,
106};
107static int bank_source[3] = {
108 TCA6507_LS_LED_PWM0,
109 TCA6507_LS_LED_PWM1,
110 TCA6507_LS_LED_MIR,
111};
112static int blink_source[2] = {
113 TCA6507_LS_BLINK0,
114 TCA6507_LS_BLINK1,
115};
116
117/* PWM registers */
118#define TCA6507_REG_CNT 11
119
120/*
121 * 0x00, 0x01, 0x02 encode the TCA6507_LS_* values, each output
122 * owns one bit in each register
123 */
124#define TCA6507_FADE_ON 0x03
125#define TCA6507_FULL_ON 0x04
126#define TCA6507_FADE_OFF 0x05
127#define TCA6507_FIRST_OFF 0x06
128#define TCA6507_SECOND_OFF 0x07
129#define TCA6507_MAX_INTENSITY 0x08
130#define TCA6507_MASTER_INTENSITY 0x09
131#define TCA6507_INITIALIZE 0x0A
132
133#define INIT_CODE 0x8
134
135#define TIMECODES 16
136static int time_codes[TIMECODES] = {
137 0, 64, 128, 192, 256, 384, 512, 768,
138 1024, 1536, 2048, 3072, 4096, 5760, 8128, 16320
139};
140
141/* Convert an led.brightness level (0..255) to a TCA6507 level (0..15) */
142static inline int TO_LEVEL(int brightness)
143{
144 return brightness >> 4;
145}
146
147/* ...and convert back */
148static inline int TO_BRIGHT(int level)
149{
150 if (level)
151 return (level << 4) | 0xf;
152 return 0;
153}
154
155#define NUM_LEDS 7
156struct tca6507_chip {
157 int reg_set; /* One bit per register where
158 * a '1' means the register
159 * should be written */
160 u8 reg_file[TCA6507_REG_CNT];
161 /* Bank 2 is Master Intensity and doesn't use times */
162 struct bank {
163 int level;
164 int ontime, offtime;
165 int on_dflt, off_dflt;
166 int time_use, level_use;
167 } bank[3];
168 struct i2c_client *client;
169 struct work_struct work;
170 spinlock_t lock;
171
172 struct tca6507_led {
173 struct tca6507_chip *chip;
174 struct led_classdev led_cdev;
175 int num;
176 int ontime, offtime;
177 int on_dflt, off_dflt;
178 int bank; /* Bank used, or -1 */
179 int blink; /* Set if hardware-blinking */
180 } leds[NUM_LEDS];
181#ifdef CONFIG_GPIOLIB
182 struct gpio_chip gpio;
183 int gpio_map[NUM_LEDS];
184#endif
185};
186
187static const struct i2c_device_id tca6507_id[] = {
188 { "tca6507" },
189 { }
190};
191MODULE_DEVICE_TABLE(i2c, tca6507_id);
192
193static int choose_times(int msec, int *c1p, int *c2p)
194{
195 /*
196 * Choose two timecodes which add to 'msec' as near as
197 * possible. The first returned is the 'on' or 'off' time.
198 * The second is to be used as a 'fade-on' or 'fade-off' time.
199 * If 'msec' is even, the first will not be smaller than the
200 * second. If 'msec' is odd, the first will not be larger
201 * than the second.
202 * If we cannot get a sum within 1/8 of 'msec' fail with
203 * -EINVAL, otherwise return the sum that was achieved, plus 1
204 * if the first is smaller.
205 * If two possibilities are equally good (e.g. 512+0,
206 * 256+256), choose the first pair so there is more
207 * change-time visible (i.e. it is softer).
208 */
209 int c1, c2;
210 int tmax = msec * 9 / 8;
211 int tmin = msec * 7 / 8;
212 int diff = 65536;
213
214 /* We start at '1' to ensure we never even think of choosing a
215 * total time of '0'.
216 */
217 for (c1 = 1; c1 < TIMECODES; c1++) {
218 int t = time_codes[c1];
219 if (t*2 < tmin)
220 continue;
221 if (t > tmax)
222 break;
223 for (c2 = 0; c2 <= c1; c2++) {
224 int tt = t + time_codes[c2];
225 int d;
226 if (tt < tmin)
227 continue;
228 if (tt > tmax)
229 break;
230 /* This works! */
231 d = abs(msec - tt);
232 if (d >= diff)
233 continue;
234 /* Best yet */
235 *c1p = c1;
236 *c2p = c2;
237 diff = d;
238 if (d == 0)
239 return msec;
240 }
241 }
242 if (diff < 65536) {
243 int actual;
244 if (msec & 1) {
245 swap(*c2p, *c1p);
246 }
247 actual = time_codes[*c1p] + time_codes[*c2p];
248 if (*c1p < *c2p)
249 return actual + 1;
250 else
251 return actual;
252 }
253 /* No close match */
254 return -EINVAL;
255}
256
257/*
258 * Update the register file with the appropriate 3-bit state for the
259 * given led.
260 */
261static void set_select(struct tca6507_chip *tca, int led, int val)
262{
263 int mask = (1 << led);
264 int bit;
265
266 for (bit = 0; bit < 3; bit++) {
267 int n = tca->reg_file[bit] & ~mask;
268 if (val & (1 << bit))
269 n |= mask;
270 if (tca->reg_file[bit] != n) {
271 tca->reg_file[bit] = n;
272 tca->reg_set |= (1 << bit);
273 }
274 }
275}
276
277/* Update the register file with the appropriate 4-bit code for one
278 * bank or other. This can be used for timers, for levels, or for
279 * initialization.
280 */
281static void set_code(struct tca6507_chip *tca, int reg, int bank, int new)
282{
283 int mask = 0xF;
284 int n;
285 if (bank) {
286 mask <<= 4;
287 new <<= 4;
288 }
289 n = tca->reg_file[reg] & ~mask;
290 n |= new;
291 if (tca->reg_file[reg] != n) {
292 tca->reg_file[reg] = n;
293 tca->reg_set |= 1 << reg;
294 }
295}
296
297/* Update brightness level. */
298static void set_level(struct tca6507_chip *tca, int bank, int level)
299{
300 switch (bank) {
301 case BANK0:
302 case BANK1:
303 set_code(tca, TCA6507_MAX_INTENSITY, bank, level);
304 break;
305 case MASTER:
306 set_code(tca, TCA6507_MASTER_INTENSITY, 0, level);
307 break;
308 }
309 tca->bank[bank].level = level;
310}
311
312/* Record all relevant time codes for a given bank */
313static void set_times(struct tca6507_chip *tca, int bank)
314{
315 int c1, c2;
316 int result;
317
318 result = choose_times(tca->bank[bank].ontime, &c1, &c2);
319 if (result < 0)
320 return;
321 dev_dbg(&tca->client->dev,
322 "Chose on times %d(%d) %d(%d) for %dms\n",
323 c1, time_codes[c1],
324 c2, time_codes[c2], tca->bank[bank].ontime);
325 set_code(tca, TCA6507_FADE_ON, bank, c2);
326 set_code(tca, TCA6507_FULL_ON, bank, c1);
327 tca->bank[bank].ontime = result;
328
329 result = choose_times(tca->bank[bank].offtime, &c1, &c2);
330 dev_dbg(&tca->client->dev,
331 "Chose off times %d(%d) %d(%d) for %dms\n",
332 c1, time_codes[c1],
333 c2, time_codes[c2], tca->bank[bank].offtime);
334 set_code(tca, TCA6507_FADE_OFF, bank, c2);
335 set_code(tca, TCA6507_FIRST_OFF, bank, c1);
336 set_code(tca, TCA6507_SECOND_OFF, bank, c1);
337 tca->bank[bank].offtime = result;
338
339 set_code(tca, TCA6507_INITIALIZE, bank, INIT_CODE);
340}
341
342/* Write all needed register of tca6507 */
343
344static void tca6507_work(struct work_struct *work)
345{
346 struct tca6507_chip *tca = container_of(work, struct tca6507_chip,
347 work);
348 struct i2c_client *cl = tca->client;
349 int set;
350 u8 file[TCA6507_REG_CNT];
351 int r;
352
353 spin_lock_irq(&tca->lock);
354 set = tca->reg_set;
355 memcpy(file, tca->reg_file, TCA6507_REG_CNT);
356 tca->reg_set = 0;
357 spin_unlock_irq(&tca->lock);
358
359 for (r = 0; r < TCA6507_REG_CNT; r++)
360 if (set & (1<<r))
361 i2c_smbus_write_byte_data(cl, r, file[r]);
362}
363
364static void led_release(struct tca6507_led *led)
365{
366 /* If led owns any resource, release it. */
367 struct tca6507_chip *tca = led->chip;
368 if (led->bank >= 0) {
369 struct bank *b = tca->bank + led->bank;
370 if (led->blink)
371 b->time_use--;
372 b->level_use--;
373 }
374 led->blink = 0;
375 led->bank = -1;
376}
377
378static int led_prepare(struct tca6507_led *led)
379{
380 /* Assign this led to a bank, configuring that bank if
381 * necessary. */
382 int level = TO_LEVEL(led->led_cdev.brightness);
383 struct tca6507_chip *tca = led->chip;
384 int c1, c2;
385 int i;
386 struct bank *b;
387 int need_init = 0;
388
389 led->led_cdev.brightness = TO_BRIGHT(level);
390 if (level == 0) {
391 set_select(tca, led->num, TCA6507_LS_LED_OFF);
392 return 0;
393 }
394
395 if (led->ontime == 0 || led->offtime == 0) {
396 /*
397 * Just set the brightness, choosing first usable
398 * bank. If none perfect, choose best. Count
399 * backwards so we check MASTER bank first to avoid
400 * wasting a timer.
401 */
402 int best = -1;/* full-on */
403 int diff = 15-level;
404
405 if (level == 15) {
406 set_select(tca, led->num, TCA6507_LS_LED_ON);
407 return 0;
408 }
409
410 for (i = MASTER; i >= BANK0; i--) {
411 int d;
412 if (tca->bank[i].level == level ||
413 tca->bank[i].level_use == 0) {
414 best = i;
415 break;
416 }
417 d = abs(level - tca->bank[i].level);
418 if (d < diff) {
419 diff = d;
420 best = i;
421 }
422 }
423 if (best == -1) {
424 /* Best brightness is full-on */
425 set_select(tca, led->num, TCA6507_LS_LED_ON);
426 led->led_cdev.brightness = LED_FULL;
427 return 0;
428 }
429
430 if (!tca->bank[best].level_use)
431 set_level(tca, best, level);
432
433 tca->bank[best].level_use++;
434 led->bank = best;
435 set_select(tca, led->num, bank_source[best]);
436 led->led_cdev.brightness = TO_BRIGHT(tca->bank[best].level);
437 return 0;
438 }
439
440 /*
441 * We have on/off time so we need to try to allocate a timing
442 * bank. First check if times are compatible with hardware
443 * and give up if not.
444 */
445 if (choose_times(led->ontime, &c1, &c2) < 0)
446 return -EINVAL;
447 if (choose_times(led->offtime, &c1, &c2) < 0)
448 return -EINVAL;
449
450 for (i = BANK0; i <= BANK1; i++) {
451 if (tca->bank[i].level_use == 0)
452 /* not in use - it is ours! */
453 break;
454 if (tca->bank[i].level != level)
455 /* Incompatible level - skip */
456 /* FIX: if timer matches we maybe should consider
457 * this anyway...
458 */
459 continue;
460
461 if (tca->bank[i].time_use == 0)
462 /* Timer not in use, and level matches - use it */
463 break;
464
465 if (!(tca->bank[i].on_dflt ||
466 led->on_dflt ||
467 tca->bank[i].ontime == led->ontime))
468 /* on time is incompatible */
469 continue;
470
471 if (!(tca->bank[i].off_dflt ||
472 led->off_dflt ||
473 tca->bank[i].offtime == led->offtime))
474 /* off time is incompatible */
475 continue;
476
477 /* looks like a suitable match */
478 break;
479 }
480
481 if (i > BANK1)
482 /* Nothing matches - how sad */
483 return -EINVAL;
484
485 b = &tca->bank[i];
486 if (b->level_use == 0)
487 set_level(tca, i, level);
488 b->level_use++;
489 led->bank = i;
490
491 if (b->on_dflt ||
492 !led->on_dflt ||
493 b->time_use == 0) {
494 b->ontime = led->ontime;
495 b->on_dflt = led->on_dflt;
496 need_init = 1;
497 }
498
499 if (b->off_dflt ||
500 !led->off_dflt ||
501 b->time_use == 0) {
502 b->offtime = led->offtime;
503 b->off_dflt = led->off_dflt;
504 need_init = 1;
505 }
506
507 if (need_init)
508 set_times(tca, i);
509
510 led->ontime = b->ontime;
511 led->offtime = b->offtime;
512
513 b->time_use++;
514 led->blink = 1;
515 led->led_cdev.brightness = TO_BRIGHT(b->level);
516 set_select(tca, led->num, blink_source[i]);
517 return 0;
518}
519
520static int led_assign(struct tca6507_led *led)
521{
522 struct tca6507_chip *tca = led->chip;
523 int err;
524 unsigned long flags;
525
526 spin_lock_irqsave(&tca->lock, flags);
527 led_release(led);
528 err = led_prepare(led);
529 if (err) {
530 /*
531 * Can only fail on timer setup. In that case we need
532 * to re-establish as steady level.
533 */
534 led->ontime = 0;
535 led->offtime = 0;
536 led_prepare(led);
537 }
538 spin_unlock_irqrestore(&tca->lock, flags);
539
540 if (tca->reg_set)
541 schedule_work(&tca->work);
542 return err;
543}
544
545static void tca6507_brightness_set(struct led_classdev *led_cdev,
546 enum led_brightness brightness)
547{
548 struct tca6507_led *led = container_of(led_cdev, struct tca6507_led,
549 led_cdev);
550 led->led_cdev.brightness = brightness;
551 led->ontime = 0;
552 led->offtime = 0;
553 led_assign(led);
554}
555
556static int tca6507_blink_set(struct led_classdev *led_cdev,
557 unsigned long *delay_on,
558 unsigned long *delay_off)
559{
560 struct tca6507_led *led = container_of(led_cdev, struct tca6507_led,
561 led_cdev);
562
563 if (*delay_on == 0)
564 led->on_dflt = 1;
565 else if (delay_on != &led_cdev->blink_delay_on)
566 led->on_dflt = 0;
567 led->ontime = *delay_on;
568
569 if (*delay_off == 0)
570 led->off_dflt = 1;
571 else if (delay_off != &led_cdev->blink_delay_off)
572 led->off_dflt = 0;
573 led->offtime = *delay_off;
574
575 if (led->ontime == 0)
576 led->ontime = 512;
577 if (led->offtime == 0)
578 led->offtime = 512;
579
580 if (led->led_cdev.brightness == LED_OFF)
581 led->led_cdev.brightness = LED_FULL;
582 if (led_assign(led) < 0) {
583 led->ontime = 0;
584 led->offtime = 0;
585 led->led_cdev.brightness = LED_OFF;
586 return -EINVAL;
587 }
588 *delay_on = led->ontime;
589 *delay_off = led->offtime;
590 return 0;
591}
592
593#ifdef CONFIG_GPIOLIB
594static void tca6507_gpio_set_value(struct gpio_chip *gc,
595 unsigned offset, int val)
596{
597 struct tca6507_chip *tca = gpiochip_get_data(gc);
598 unsigned long flags;
599
600 spin_lock_irqsave(&tca->lock, flags);
601 /*
602 * 'OFF' is floating high, and 'ON' is pulled down, so it has
603 * the inverse sense of 'val'.
604 */
605 set_select(tca, tca->gpio_map[offset],
606 val ? TCA6507_LS_LED_OFF : TCA6507_LS_LED_ON);
607 spin_unlock_irqrestore(&tca->lock, flags);
608 if (tca->reg_set)
609 schedule_work(&tca->work);
610}
611
612static int tca6507_gpio_direction_output(struct gpio_chip *gc,
613 unsigned offset, int val)
614{
615 tca6507_gpio_set_value(gc, offset, val);
616 return 0;
617}
618
619static int tca6507_probe_gpios(struct device *dev,
620 struct tca6507_chip *tca,
621 struct tca6507_platform_data *pdata)
622{
623 int err;
624 int i = 0;
625 int gpios = 0;
626
627 for (i = 0; i < NUM_LEDS; i++)
628 if (pdata->leds.leds[i].name && pdata->leds.leds[i].flags) {
629 /* Configure as a gpio */
630 tca->gpio_map[gpios] = i;
631 gpios++;
632 }
633
634 if (!gpios)
635 return 0;
636
637 tca->gpio.label = "gpio-tca6507";
638 tca->gpio.ngpio = gpios;
639 tca->gpio.base = pdata->gpio_base;
640 tca->gpio.owner = THIS_MODULE;
641 tca->gpio.direction_output = tca6507_gpio_direction_output;
642 tca->gpio.set = tca6507_gpio_set_value;
643 tca->gpio.parent = dev;
644 err = gpiochip_add_data(&tca->gpio, tca);
645 if (err) {
646 tca->gpio.ngpio = 0;
647 return err;
648 }
649 return 0;
650}
651
652static void tca6507_remove_gpio(struct tca6507_chip *tca)
653{
654 if (tca->gpio.ngpio)
655 gpiochip_remove(&tca->gpio);
656}
657#else /* CONFIG_GPIOLIB */
658static int tca6507_probe_gpios(struct device *dev,
659 struct tca6507_chip *tca,
660 struct tca6507_platform_data *pdata)
661{
662 return 0;
663}
664static void tca6507_remove_gpio(struct tca6507_chip *tca)
665{
666}
667#endif /* CONFIG_GPIOLIB */
668
669static struct tca6507_platform_data *
670tca6507_led_dt_init(struct device *dev)
671{
672 struct tca6507_platform_data *pdata;
673 struct fwnode_handle *child;
674 struct led_info *tca_leds;
675 int count;
676
677 count = device_get_child_node_count(dev);
678 if (!count || count > NUM_LEDS)
679 return ERR_PTR(-ENODEV);
680
681 tca_leds = devm_kcalloc(dev, NUM_LEDS, sizeof(struct led_info),
682 GFP_KERNEL);
683 if (!tca_leds)
684 return ERR_PTR(-ENOMEM);
685
686 device_for_each_child_node(dev, child) {
687 struct led_info led;
688 u32 reg;
689 int ret;
690
691 if (fwnode_property_read_string(child, "label", &led.name))
692 led.name = fwnode_get_name(child);
693
694 fwnode_property_read_string(child, "linux,default-trigger",
695 &led.default_trigger);
696
697 led.flags = 0;
698 if (fwnode_property_match_string(child, "compatible",
699 "gpio") >= 0)
700 led.flags |= TCA6507_MAKE_GPIO;
701
702 ret = fwnode_property_read_u32(child, "reg", ®);
703 if (ret || reg >= NUM_LEDS) {
704 fwnode_handle_put(child);
705 return ERR_PTR(ret ? : -EINVAL);
706 }
707
708 tca_leds[reg] = led;
709 }
710
711 pdata = devm_kzalloc(dev, sizeof(struct tca6507_platform_data),
712 GFP_KERNEL);
713 if (!pdata)
714 return ERR_PTR(-ENOMEM);
715
716 pdata->leds.leds = tca_leds;
717 pdata->leds.num_leds = NUM_LEDS;
718#ifdef CONFIG_GPIOLIB
719 pdata->gpio_base = -1;
720#endif
721
722 return pdata;
723}
724
725static const struct of_device_id __maybe_unused of_tca6507_leds_match[] = {
726 { .compatible = "ti,tca6507", },
727 {},
728};
729MODULE_DEVICE_TABLE(of, of_tca6507_leds_match);
730
731static int tca6507_probe(struct i2c_client *client,
732 const struct i2c_device_id *id)
733{
734 struct device *dev = &client->dev;
735 struct i2c_adapter *adapter;
736 struct tca6507_chip *tca;
737 struct tca6507_platform_data *pdata;
738 int err;
739 int i = 0;
740
741 adapter = client->adapter;
742
743 if (!i2c_check_functionality(adapter, I2C_FUNC_I2C))
744 return -EIO;
745
746 pdata = tca6507_led_dt_init(dev);
747 if (IS_ERR(pdata)) {
748 dev_err(dev, "Need %d entries in platform-data list\n", NUM_LEDS);
749 return PTR_ERR(pdata);
750 }
751 tca = devm_kzalloc(dev, sizeof(*tca), GFP_KERNEL);
752 if (!tca)
753 return -ENOMEM;
754
755 tca->client = client;
756 INIT_WORK(&tca->work, tca6507_work);
757 spin_lock_init(&tca->lock);
758 i2c_set_clientdata(client, tca);
759
760 for (i = 0; i < NUM_LEDS; i++) {
761 struct tca6507_led *l = tca->leds + i;
762
763 l->chip = tca;
764 l->num = i;
765 if (pdata->leds.leds[i].name && !pdata->leds.leds[i].flags) {
766 l->led_cdev.name = pdata->leds.leds[i].name;
767 l->led_cdev.default_trigger
768 = pdata->leds.leds[i].default_trigger;
769 l->led_cdev.brightness_set = tca6507_brightness_set;
770 l->led_cdev.blink_set = tca6507_blink_set;
771 l->bank = -1;
772 err = led_classdev_register(dev, &l->led_cdev);
773 if (err < 0)
774 goto exit;
775 }
776 }
777 err = tca6507_probe_gpios(dev, tca, pdata);
778 if (err)
779 goto exit;
780 /* set all registers to known state - zero */
781 tca->reg_set = 0x7f;
782 schedule_work(&tca->work);
783
784 return 0;
785exit:
786 while (i--) {
787 if (tca->leds[i].led_cdev.name)
788 led_classdev_unregister(&tca->leds[i].led_cdev);
789 }
790 return err;
791}
792
793static void tca6507_remove(struct i2c_client *client)
794{
795 int i;
796 struct tca6507_chip *tca = i2c_get_clientdata(client);
797 struct tca6507_led *tca_leds = tca->leds;
798
799 for (i = 0; i < NUM_LEDS; i++) {
800 if (tca_leds[i].led_cdev.name)
801 led_classdev_unregister(&tca_leds[i].led_cdev);
802 }
803 tca6507_remove_gpio(tca);
804 cancel_work_sync(&tca->work);
805}
806
807static struct i2c_driver tca6507_driver = {
808 .driver = {
809 .name = "leds-tca6507",
810 .of_match_table = of_match_ptr(of_tca6507_leds_match),
811 },
812 .probe = tca6507_probe,
813 .remove = tca6507_remove,
814 .id_table = tca6507_id,
815};
816
817module_i2c_driver(tca6507_driver);
818
819MODULE_AUTHOR("NeilBrown <neilb@suse.de>");
820MODULE_DESCRIPTION("TCA6507 LED/GPO driver");
821MODULE_LICENSE("GPL v2");
1/*
2 * leds-tca6507
3 *
4 * The TCA6507 is a programmable LED controller that can drive 7
5 * separate lines either by holding them low, or by pulsing them
6 * with modulated width.
7 * The modulation can be varied in a simple pattern to produce a
8 * blink or double-blink.
9 *
10 * This driver can configure each line either as a 'GPIO' which is
11 * out-only (pull-up resistor required) or as an LED with variable
12 * brightness and hardware-assisted blinking.
13 *
14 * Apart from OFF and ON there are three programmable brightness
15 * levels which can be programmed from 0 to 15 and indicate how many
16 * 500usec intervals in each 8msec that the led is 'on'. The levels
17 * are named MASTER, BANK0 and BANK1.
18 *
19 * There are two different blink rates that can be programmed, each
20 * with separate time for rise, on, fall, off and second-off. Thus if
21 * 3 or more different non-trivial rates are required, software must
22 * be used for the extra rates. The two different blink rates must
23 * align with the two levels BANK0 and BANK1. This driver does not
24 * support double-blink so 'second-off' always matches 'off'.
25 *
26 * Only 16 different times can be programmed in a roughly logarithmic
27 * scale from 64ms to 16320ms. To be precise the possible times are:
28 * 0, 64, 128, 192, 256, 384, 512, 768,
29 * 1024, 1536, 2048, 3072, 4096, 5760, 8128, 16320
30 *
31 * Times that cannot be closely matched with these must be handled in
32 * software. This driver allows 12.5% error in matching.
33 *
34 * This driver does not allow rise/fall rates to be set explicitly.
35 * When trying to match a given 'on' or 'off' period, an appropriate
36 * pair of 'change' and 'hold' times are chosen to get a close match.
37 * If the target delay is even, the 'change' number will be the
38 * smaller; if odd, the 'hold' number will be the smaller.
39
40 * Choosing pairs of delays with 12.5% errors allows us to match
41 * delays in the ranges: 56-72, 112-144, 168-216, 224-27504,
42 * 28560-36720.
43 * 26% of the achievable sums can be matched by multiple pairings.
44 * For example 1536 == 1536+0, 1024+512, or 768+768.
45 * This driver will always choose the pairing with the least
46 * maximum - 768+768 in this case. Other pairings are not available.
47 *
48 * Access to the 3 levels and 2 blinks are on a first-come,
49 * first-served basis. Access can be shared by multiple leds if they
50 * have the same level and either same blink rates, or some don't
51 * blink. When a led changes, it relinquishes access and tries again,
52 * so it might lose access to hardware blink.
53 *
54 * If a blink engine cannot be allocated, software blink is used. If
55 * the desired brightness cannot be allocated, the closest available
56 * non-zero brightness is used. As 'full' is always available, the
57 * worst case would be to have two different blink rates at '1', with
58 * Max at '2', then other leds will have to choose between '2' and
59 * '16'. Hopefully this is not likely.
60 *
61 * Each bank (BANK0 and BANK1) has two usage counts - LEDs using the
62 * brightness and LEDs using the blink. It can only be reprogrammed
63 * when the appropriate counter is zero. The MASTER level has a
64 * single usage count.
65 *
66 * Each LED has programmable 'on' and 'off' time as milliseconds.
67 * With each there is a flag saying if it was explicitly requested or
68 * defaulted. Similarly the banks know if each time was explicit or a
69 * default. Defaults are permitted to be changed freely - they are
70 * not recognised when matching.
71 *
72 *
73 * An led-tca6507 device must be provided with platform data or
74 * configured via devicetree.
75 *
76 * The platform-data lists for each output: the name, default trigger,
77 * and whether the signal is being used as a GPIO rather than an LED.
78 * 'struct led_plaform_data' is used for this. If 'name' is NULL, the
79 * output isn't used. If 'flags' is TCA6507_MAKE_GPIO, the output is
80 * a GPO. The "struct led_platform_data" can be embedded in a "struct
81 * tca6507_platform_data" which adds a 'gpio_base' for the GPIOs, and
82 * a 'setup' callback which is called once the GPIOs are available.
83 *
84 * When configured via devicetree there is one child for each output.
85 * The "reg" determines the output number and "compatible" determines
86 * whether it is an LED or a GPIO. "linux,default-trigger" can set a
87 * default trigger.
88 */
89
90#include <linux/module.h>
91#include <linux/slab.h>
92#include <linux/leds.h>
93#include <linux/err.h>
94#include <linux/i2c.h>
95#include <linux/gpio.h>
96#include <linux/workqueue.h>
97#include <linux/leds-tca6507.h>
98#include <linux/of.h>
99
100/* LED select registers determine the source that drives LED outputs */
101#define TCA6507_LS_LED_OFF 0x0 /* Output HI-Z (off) */
102#define TCA6507_LS_LED_OFF1 0x1 /* Output HI-Z (off) - not used */
103#define TCA6507_LS_LED_PWM0 0x2 /* Output LOW with Bank0 rate */
104#define TCA6507_LS_LED_PWM1 0x3 /* Output LOW with Bank1 rate */
105#define TCA6507_LS_LED_ON 0x4 /* Output LOW (on) */
106#define TCA6507_LS_LED_MIR 0x5 /* Output LOW with Master Intensity */
107#define TCA6507_LS_BLINK0 0x6 /* Blink at Bank0 rate */
108#define TCA6507_LS_BLINK1 0x7 /* Blink at Bank1 rate */
109
110enum {
111 BANK0,
112 BANK1,
113 MASTER,
114};
115static int bank_source[3] = {
116 TCA6507_LS_LED_PWM0,
117 TCA6507_LS_LED_PWM1,
118 TCA6507_LS_LED_MIR,
119};
120static int blink_source[2] = {
121 TCA6507_LS_BLINK0,
122 TCA6507_LS_BLINK1,
123};
124
125/* PWM registers */
126#define TCA6507_REG_CNT 11
127
128/*
129 * 0x00, 0x01, 0x02 encode the TCA6507_LS_* values, each output
130 * owns one bit in each register
131 */
132#define TCA6507_FADE_ON 0x03
133#define TCA6507_FULL_ON 0x04
134#define TCA6507_FADE_OFF 0x05
135#define TCA6507_FIRST_OFF 0x06
136#define TCA6507_SECOND_OFF 0x07
137#define TCA6507_MAX_INTENSITY 0x08
138#define TCA6507_MASTER_INTENSITY 0x09
139#define TCA6507_INITIALIZE 0x0A
140
141#define INIT_CODE 0x8
142
143#define TIMECODES 16
144static int time_codes[TIMECODES] = {
145 0, 64, 128, 192, 256, 384, 512, 768,
146 1024, 1536, 2048, 3072, 4096, 5760, 8128, 16320
147};
148
149/* Convert an led.brightness level (0..255) to a TCA6507 level (0..15) */
150static inline int TO_LEVEL(int brightness)
151{
152 return brightness >> 4;
153}
154
155/* ...and convert back */
156static inline int TO_BRIGHT(int level)
157{
158 if (level)
159 return (level << 4) | 0xf;
160 return 0;
161}
162
163#define NUM_LEDS 7
164struct tca6507_chip {
165 int reg_set; /* One bit per register where
166 * a '1' means the register
167 * should be written */
168 u8 reg_file[TCA6507_REG_CNT];
169 /* Bank 2 is Master Intensity and doesn't use times */
170 struct bank {
171 int level;
172 int ontime, offtime;
173 int on_dflt, off_dflt;
174 int time_use, level_use;
175 } bank[3];
176 struct i2c_client *client;
177 struct work_struct work;
178 spinlock_t lock;
179
180 struct tca6507_led {
181 struct tca6507_chip *chip;
182 struct led_classdev led_cdev;
183 int num;
184 int ontime, offtime;
185 int on_dflt, off_dflt;
186 int bank; /* Bank used, or -1 */
187 int blink; /* Set if hardware-blinking */
188 } leds[NUM_LEDS];
189#ifdef CONFIG_GPIOLIB
190 struct gpio_chip gpio;
191 const char *gpio_name[NUM_LEDS];
192 int gpio_map[NUM_LEDS];
193#endif
194};
195
196static const struct i2c_device_id tca6507_id[] = {
197 { "tca6507" },
198 { }
199};
200MODULE_DEVICE_TABLE(i2c, tca6507_id);
201
202static int choose_times(int msec, int *c1p, int *c2p)
203{
204 /*
205 * Choose two timecodes which add to 'msec' as near as
206 * possible. The first returned is the 'on' or 'off' time.
207 * The second is to be used as a 'fade-on' or 'fade-off' time.
208 * If 'msec' is even, the first will not be smaller than the
209 * second. If 'msec' is odd, the first will not be larger
210 * than the second.
211 * If we cannot get a sum within 1/8 of 'msec' fail with
212 * -EINVAL, otherwise return the sum that was achieved, plus 1
213 * if the first is smaller.
214 * If two possibilities are equally good (e.g. 512+0,
215 * 256+256), choose the first pair so there is more
216 * change-time visible (i.e. it is softer).
217 */
218 int c1, c2;
219 int tmax = msec * 9 / 8;
220 int tmin = msec * 7 / 8;
221 int diff = 65536;
222
223 /* We start at '1' to ensure we never even think of choosing a
224 * total time of '0'.
225 */
226 for (c1 = 1; c1 < TIMECODES; c1++) {
227 int t = time_codes[c1];
228 if (t*2 < tmin)
229 continue;
230 if (t > tmax)
231 break;
232 for (c2 = 0; c2 <= c1; c2++) {
233 int tt = t + time_codes[c2];
234 int d;
235 if (tt < tmin)
236 continue;
237 if (tt > tmax)
238 break;
239 /* This works! */
240 d = abs(msec - tt);
241 if (d >= diff)
242 continue;
243 /* Best yet */
244 *c1p = c1;
245 *c2p = c2;
246 diff = d;
247 if (d == 0)
248 return msec;
249 }
250 }
251 if (diff < 65536) {
252 int actual;
253 if (msec & 1) {
254 c1 = *c2p;
255 *c2p = *c1p;
256 *c1p = c1;
257 }
258 actual = time_codes[*c1p] + time_codes[*c2p];
259 if (*c1p < *c2p)
260 return actual + 1;
261 else
262 return actual;
263 }
264 /* No close match */
265 return -EINVAL;
266}
267
268/*
269 * Update the register file with the appropriate 3-bit state for the
270 * given led.
271 */
272static void set_select(struct tca6507_chip *tca, int led, int val)
273{
274 int mask = (1 << led);
275 int bit;
276
277 for (bit = 0; bit < 3; bit++) {
278 int n = tca->reg_file[bit] & ~mask;
279 if (val & (1 << bit))
280 n |= mask;
281 if (tca->reg_file[bit] != n) {
282 tca->reg_file[bit] = n;
283 tca->reg_set |= (1 << bit);
284 }
285 }
286}
287
288/* Update the register file with the appropriate 4-bit code for one
289 * bank or other. This can be used for timers, for levels, or for
290 * initialization.
291 */
292static void set_code(struct tca6507_chip *tca, int reg, int bank, int new)
293{
294 int mask = 0xF;
295 int n;
296 if (bank) {
297 mask <<= 4;
298 new <<= 4;
299 }
300 n = tca->reg_file[reg] & ~mask;
301 n |= new;
302 if (tca->reg_file[reg] != n) {
303 tca->reg_file[reg] = n;
304 tca->reg_set |= 1 << reg;
305 }
306}
307
308/* Update brightness level. */
309static void set_level(struct tca6507_chip *tca, int bank, int level)
310{
311 switch (bank) {
312 case BANK0:
313 case BANK1:
314 set_code(tca, TCA6507_MAX_INTENSITY, bank, level);
315 break;
316 case MASTER:
317 set_code(tca, TCA6507_MASTER_INTENSITY, 0, level);
318 break;
319 }
320 tca->bank[bank].level = level;
321}
322
323/* Record all relevant time codes for a given bank */
324static void set_times(struct tca6507_chip *tca, int bank)
325{
326 int c1, c2;
327 int result;
328
329 result = choose_times(tca->bank[bank].ontime, &c1, &c2);
330 dev_dbg(&tca->client->dev,
331 "Chose on times %d(%d) %d(%d) for %dms\n",
332 c1, time_codes[c1],
333 c2, time_codes[c2], tca->bank[bank].ontime);
334 set_code(tca, TCA6507_FADE_ON, bank, c2);
335 set_code(tca, TCA6507_FULL_ON, bank, c1);
336 tca->bank[bank].ontime = result;
337
338 result = choose_times(tca->bank[bank].offtime, &c1, &c2);
339 dev_dbg(&tca->client->dev,
340 "Chose off times %d(%d) %d(%d) for %dms\n",
341 c1, time_codes[c1],
342 c2, time_codes[c2], tca->bank[bank].offtime);
343 set_code(tca, TCA6507_FADE_OFF, bank, c2);
344 set_code(tca, TCA6507_FIRST_OFF, bank, c1);
345 set_code(tca, TCA6507_SECOND_OFF, bank, c1);
346 tca->bank[bank].offtime = result;
347
348 set_code(tca, TCA6507_INITIALIZE, bank, INIT_CODE);
349}
350
351/* Write all needed register of tca6507 */
352
353static void tca6507_work(struct work_struct *work)
354{
355 struct tca6507_chip *tca = container_of(work, struct tca6507_chip,
356 work);
357 struct i2c_client *cl = tca->client;
358 int set;
359 u8 file[TCA6507_REG_CNT];
360 int r;
361
362 spin_lock_irq(&tca->lock);
363 set = tca->reg_set;
364 memcpy(file, tca->reg_file, TCA6507_REG_CNT);
365 tca->reg_set = 0;
366 spin_unlock_irq(&tca->lock);
367
368 for (r = 0; r < TCA6507_REG_CNT; r++)
369 if (set & (1<<r))
370 i2c_smbus_write_byte_data(cl, r, file[r]);
371}
372
373static void led_release(struct tca6507_led *led)
374{
375 /* If led owns any resource, release it. */
376 struct tca6507_chip *tca = led->chip;
377 if (led->bank >= 0) {
378 struct bank *b = tca->bank + led->bank;
379 if (led->blink)
380 b->time_use--;
381 b->level_use--;
382 }
383 led->blink = 0;
384 led->bank = -1;
385}
386
387static int led_prepare(struct tca6507_led *led)
388{
389 /* Assign this led to a bank, configuring that bank if
390 * necessary. */
391 int level = TO_LEVEL(led->led_cdev.brightness);
392 struct tca6507_chip *tca = led->chip;
393 int c1, c2;
394 int i;
395 struct bank *b;
396 int need_init = 0;
397
398 led->led_cdev.brightness = TO_BRIGHT(level);
399 if (level == 0) {
400 set_select(tca, led->num, TCA6507_LS_LED_OFF);
401 return 0;
402 }
403
404 if (led->ontime == 0 || led->offtime == 0) {
405 /*
406 * Just set the brightness, choosing first usable
407 * bank. If none perfect, choose best. Count
408 * backwards so we check MASTER bank first to avoid
409 * wasting a timer.
410 */
411 int best = -1;/* full-on */
412 int diff = 15-level;
413
414 if (level == 15) {
415 set_select(tca, led->num, TCA6507_LS_LED_ON);
416 return 0;
417 }
418
419 for (i = MASTER; i >= BANK0; i--) {
420 int d;
421 if (tca->bank[i].level == level ||
422 tca->bank[i].level_use == 0) {
423 best = i;
424 break;
425 }
426 d = abs(level - tca->bank[i].level);
427 if (d < diff) {
428 diff = d;
429 best = i;
430 }
431 }
432 if (best == -1) {
433 /* Best brightness is full-on */
434 set_select(tca, led->num, TCA6507_LS_LED_ON);
435 led->led_cdev.brightness = LED_FULL;
436 return 0;
437 }
438
439 if (!tca->bank[best].level_use)
440 set_level(tca, best, level);
441
442 tca->bank[best].level_use++;
443 led->bank = best;
444 set_select(tca, led->num, bank_source[best]);
445 led->led_cdev.brightness = TO_BRIGHT(tca->bank[best].level);
446 return 0;
447 }
448
449 /*
450 * We have on/off time so we need to try to allocate a timing
451 * bank. First check if times are compatible with hardware
452 * and give up if not.
453 */
454 if (choose_times(led->ontime, &c1, &c2) < 0)
455 return -EINVAL;
456 if (choose_times(led->offtime, &c1, &c2) < 0)
457 return -EINVAL;
458
459 for (i = BANK0; i <= BANK1; i++) {
460 if (tca->bank[i].level_use == 0)
461 /* not in use - it is ours! */
462 break;
463 if (tca->bank[i].level != level)
464 /* Incompatible level - skip */
465 /* FIX: if timer matches we maybe should consider
466 * this anyway...
467 */
468 continue;
469
470 if (tca->bank[i].time_use == 0)
471 /* Timer not in use, and level matches - use it */
472 break;
473
474 if (!(tca->bank[i].on_dflt ||
475 led->on_dflt ||
476 tca->bank[i].ontime == led->ontime))
477 /* on time is incompatible */
478 continue;
479
480 if (!(tca->bank[i].off_dflt ||
481 led->off_dflt ||
482 tca->bank[i].offtime == led->offtime))
483 /* off time is incompatible */
484 continue;
485
486 /* looks like a suitable match */
487 break;
488 }
489
490 if (i > BANK1)
491 /* Nothing matches - how sad */
492 return -EINVAL;
493
494 b = &tca->bank[i];
495 if (b->level_use == 0)
496 set_level(tca, i, level);
497 b->level_use++;
498 led->bank = i;
499
500 if (b->on_dflt ||
501 !led->on_dflt ||
502 b->time_use == 0) {
503 b->ontime = led->ontime;
504 b->on_dflt = led->on_dflt;
505 need_init = 1;
506 }
507
508 if (b->off_dflt ||
509 !led->off_dflt ||
510 b->time_use == 0) {
511 b->offtime = led->offtime;
512 b->off_dflt = led->off_dflt;
513 need_init = 1;
514 }
515
516 if (need_init)
517 set_times(tca, i);
518
519 led->ontime = b->ontime;
520 led->offtime = b->offtime;
521
522 b->time_use++;
523 led->blink = 1;
524 led->led_cdev.brightness = TO_BRIGHT(b->level);
525 set_select(tca, led->num, blink_source[i]);
526 return 0;
527}
528
529static int led_assign(struct tca6507_led *led)
530{
531 struct tca6507_chip *tca = led->chip;
532 int err;
533 unsigned long flags;
534
535 spin_lock_irqsave(&tca->lock, flags);
536 led_release(led);
537 err = led_prepare(led);
538 if (err) {
539 /*
540 * Can only fail on timer setup. In that case we need
541 * to re-establish as steady level.
542 */
543 led->ontime = 0;
544 led->offtime = 0;
545 led_prepare(led);
546 }
547 spin_unlock_irqrestore(&tca->lock, flags);
548
549 if (tca->reg_set)
550 schedule_work(&tca->work);
551 return err;
552}
553
554static void tca6507_brightness_set(struct led_classdev *led_cdev,
555 enum led_brightness brightness)
556{
557 struct tca6507_led *led = container_of(led_cdev, struct tca6507_led,
558 led_cdev);
559 led->led_cdev.brightness = brightness;
560 led->ontime = 0;
561 led->offtime = 0;
562 led_assign(led);
563}
564
565static int tca6507_blink_set(struct led_classdev *led_cdev,
566 unsigned long *delay_on,
567 unsigned long *delay_off)
568{
569 struct tca6507_led *led = container_of(led_cdev, struct tca6507_led,
570 led_cdev);
571
572 if (*delay_on == 0)
573 led->on_dflt = 1;
574 else if (delay_on != &led_cdev->blink_delay_on)
575 led->on_dflt = 0;
576 led->ontime = *delay_on;
577
578 if (*delay_off == 0)
579 led->off_dflt = 1;
580 else if (delay_off != &led_cdev->blink_delay_off)
581 led->off_dflt = 0;
582 led->offtime = *delay_off;
583
584 if (led->ontime == 0)
585 led->ontime = 512;
586 if (led->offtime == 0)
587 led->offtime = 512;
588
589 if (led->led_cdev.brightness == LED_OFF)
590 led->led_cdev.brightness = LED_FULL;
591 if (led_assign(led) < 0) {
592 led->ontime = 0;
593 led->offtime = 0;
594 led->led_cdev.brightness = LED_OFF;
595 return -EINVAL;
596 }
597 *delay_on = led->ontime;
598 *delay_off = led->offtime;
599 return 0;
600}
601
602#ifdef CONFIG_GPIOLIB
603static void tca6507_gpio_set_value(struct gpio_chip *gc,
604 unsigned offset, int val)
605{
606 struct tca6507_chip *tca = gpiochip_get_data(gc);
607 unsigned long flags;
608
609 spin_lock_irqsave(&tca->lock, flags);
610 /*
611 * 'OFF' is floating high, and 'ON' is pulled down, so it has
612 * the inverse sense of 'val'.
613 */
614 set_select(tca, tca->gpio_map[offset],
615 val ? TCA6507_LS_LED_OFF : TCA6507_LS_LED_ON);
616 spin_unlock_irqrestore(&tca->lock, flags);
617 if (tca->reg_set)
618 schedule_work(&tca->work);
619}
620
621static int tca6507_gpio_direction_output(struct gpio_chip *gc,
622 unsigned offset, int val)
623{
624 tca6507_gpio_set_value(gc, offset, val);
625 return 0;
626}
627
628static int tca6507_probe_gpios(struct i2c_client *client,
629 struct tca6507_chip *tca,
630 struct tca6507_platform_data *pdata)
631{
632 int err;
633 int i = 0;
634 int gpios = 0;
635
636 for (i = 0; i < NUM_LEDS; i++)
637 if (pdata->leds.leds[i].name && pdata->leds.leds[i].flags) {
638 /* Configure as a gpio */
639 tca->gpio_name[gpios] = pdata->leds.leds[i].name;
640 tca->gpio_map[gpios] = i;
641 gpios++;
642 }
643
644 if (!gpios)
645 return 0;
646
647 tca->gpio.label = "gpio-tca6507";
648 tca->gpio.names = tca->gpio_name;
649 tca->gpio.ngpio = gpios;
650 tca->gpio.base = pdata->gpio_base;
651 tca->gpio.owner = THIS_MODULE;
652 tca->gpio.direction_output = tca6507_gpio_direction_output;
653 tca->gpio.set = tca6507_gpio_set_value;
654 tca->gpio.parent = &client->dev;
655#ifdef CONFIG_OF_GPIO
656 tca->gpio.of_node = of_node_get(client->dev.of_node);
657#endif
658 err = gpiochip_add_data(&tca->gpio, tca);
659 if (err) {
660 tca->gpio.ngpio = 0;
661 return err;
662 }
663 if (pdata->setup)
664 pdata->setup(tca->gpio.base, tca->gpio.ngpio);
665 return 0;
666}
667
668static void tca6507_remove_gpio(struct tca6507_chip *tca)
669{
670 if (tca->gpio.ngpio)
671 gpiochip_remove(&tca->gpio);
672}
673#else /* CONFIG_GPIOLIB */
674static int tca6507_probe_gpios(struct i2c_client *client,
675 struct tca6507_chip *tca,
676 struct tca6507_platform_data *pdata)
677{
678 return 0;
679}
680static void tca6507_remove_gpio(struct tca6507_chip *tca)
681{
682}
683#endif /* CONFIG_GPIOLIB */
684
685#ifdef CONFIG_OF
686static struct tca6507_platform_data *
687tca6507_led_dt_init(struct i2c_client *client)
688{
689 struct device_node *np = client->dev.of_node, *child;
690 struct tca6507_platform_data *pdata;
691 struct led_info *tca_leds;
692 int count;
693
694 count = of_get_child_count(np);
695 if (!count || count > NUM_LEDS)
696 return ERR_PTR(-ENODEV);
697
698 tca_leds = devm_kzalloc(&client->dev,
699 sizeof(struct led_info) * NUM_LEDS, GFP_KERNEL);
700 if (!tca_leds)
701 return ERR_PTR(-ENOMEM);
702
703 for_each_child_of_node(np, child) {
704 struct led_info led;
705 u32 reg;
706 int ret;
707
708 led.name =
709 of_get_property(child, "label", NULL) ? : child->name;
710 led.default_trigger =
711 of_get_property(child, "linux,default-trigger", NULL);
712 led.flags = 0;
713 if (of_property_match_string(child, "compatible", "gpio") >= 0)
714 led.flags |= TCA6507_MAKE_GPIO;
715 ret = of_property_read_u32(child, "reg", ®);
716 if (ret != 0 || reg < 0 || reg >= NUM_LEDS)
717 continue;
718
719 tca_leds[reg] = led;
720 }
721 pdata = devm_kzalloc(&client->dev,
722 sizeof(struct tca6507_platform_data), GFP_KERNEL);
723 if (!pdata)
724 return ERR_PTR(-ENOMEM);
725
726 pdata->leds.leds = tca_leds;
727 pdata->leds.num_leds = NUM_LEDS;
728#ifdef CONFIG_GPIOLIB
729 pdata->gpio_base = -1;
730#endif
731 return pdata;
732}
733
734static const struct of_device_id of_tca6507_leds_match[] = {
735 { .compatible = "ti,tca6507", },
736 {},
737};
738MODULE_DEVICE_TABLE(of, of_tca6507_leds_match);
739
740#else
741static struct tca6507_platform_data *
742tca6507_led_dt_init(struct i2c_client *client)
743{
744 return ERR_PTR(-ENODEV);
745}
746
747#endif
748
749static int tca6507_probe(struct i2c_client *client,
750 const struct i2c_device_id *id)
751{
752 struct tca6507_chip *tca;
753 struct i2c_adapter *adapter;
754 struct tca6507_platform_data *pdata;
755 int err;
756 int i = 0;
757
758 adapter = to_i2c_adapter(client->dev.parent);
759 pdata = dev_get_platdata(&client->dev);
760
761 if (!i2c_check_functionality(adapter, I2C_FUNC_I2C))
762 return -EIO;
763
764 if (!pdata || pdata->leds.num_leds != NUM_LEDS) {
765 pdata = tca6507_led_dt_init(client);
766 if (IS_ERR(pdata)) {
767 dev_err(&client->dev, "Need %d entries in platform-data list\n",
768 NUM_LEDS);
769 return PTR_ERR(pdata);
770 }
771 }
772 tca = devm_kzalloc(&client->dev, sizeof(*tca), GFP_KERNEL);
773 if (!tca)
774 return -ENOMEM;
775
776 tca->client = client;
777 INIT_WORK(&tca->work, tca6507_work);
778 spin_lock_init(&tca->lock);
779 i2c_set_clientdata(client, tca);
780
781 for (i = 0; i < NUM_LEDS; i++) {
782 struct tca6507_led *l = tca->leds + i;
783
784 l->chip = tca;
785 l->num = i;
786 if (pdata->leds.leds[i].name && !pdata->leds.leds[i].flags) {
787 l->led_cdev.name = pdata->leds.leds[i].name;
788 l->led_cdev.default_trigger
789 = pdata->leds.leds[i].default_trigger;
790 l->led_cdev.brightness_set = tca6507_brightness_set;
791 l->led_cdev.blink_set = tca6507_blink_set;
792 l->bank = -1;
793 err = led_classdev_register(&client->dev,
794 &l->led_cdev);
795 if (err < 0)
796 goto exit;
797 }
798 }
799 err = tca6507_probe_gpios(client, tca, pdata);
800 if (err)
801 goto exit;
802 /* set all registers to known state - zero */
803 tca->reg_set = 0x7f;
804 schedule_work(&tca->work);
805
806 return 0;
807exit:
808 while (i--) {
809 if (tca->leds[i].led_cdev.name)
810 led_classdev_unregister(&tca->leds[i].led_cdev);
811 }
812 return err;
813}
814
815static int tca6507_remove(struct i2c_client *client)
816{
817 int i;
818 struct tca6507_chip *tca = i2c_get_clientdata(client);
819 struct tca6507_led *tca_leds = tca->leds;
820
821 for (i = 0; i < NUM_LEDS; i++) {
822 if (tca_leds[i].led_cdev.name)
823 led_classdev_unregister(&tca_leds[i].led_cdev);
824 }
825 tca6507_remove_gpio(tca);
826 cancel_work_sync(&tca->work);
827
828 return 0;
829}
830
831static struct i2c_driver tca6507_driver = {
832 .driver = {
833 .name = "leds-tca6507",
834 .of_match_table = of_match_ptr(of_tca6507_leds_match),
835 },
836 .probe = tca6507_probe,
837 .remove = tca6507_remove,
838 .id_table = tca6507_id,
839};
840
841module_i2c_driver(tca6507_driver);
842
843MODULE_AUTHOR("NeilBrown <neilb@suse.de>");
844MODULE_DESCRIPTION("TCA6507 LED/GPO driver");
845MODULE_LICENSE("GPL v2");