1 // SPDX-License-Identifier: GPL-2.0-only
3  * leds-tca6507
8  * The modulation can be varied in a simple pattern to produce a
9  * blink or double-blink.
12  * out-only (pull-up resistor required) or as an LED with variable
13  * brightness and hardware-assisted blinking.
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
25  * support double-blink so 'second-off' always matches 'off'.
42  * delays in the ranges: 56-72, 112-144, 168-216, 224-27504,
43  * 28560-36720.
47  * maximum - 768+768 in this case.  Other pairings are not available.
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
57  * non-zero brightness is used.  As 'full' is always available, the
59  * Max at '2', then other leds will have to choose between '2' and
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
70  * default.  Defaults are permitted to be changed freely - they are
76 #include <linux/leds.h>
84 #define TCA6507_LS_LED_OFF	0x0	/* Output HI-Z (off) */
85 #define TCA6507_LS_LED_OFF1	0x1	/* Output HI-Z (off) - not used */
94 	struct led_platform_data leds;  member
175 		int			bank;	/* Bank used, or -1 */
176 		int			blink;	/* Set if hardware-blinking */
177 	} leds[NUM_LEDS];  member
195 	 * The second is to be used as a 'fade-on' or 'fade-off' time.  in choose_times()
200 	 * -EINVAL, otherwise return the sum that was achieved, plus 1  in choose_times()
204 	 * change-time visible (i.e. it is softer).  in choose_times()
228 			d = abs(msec - tt);  in choose_times()
251 	return -EINVAL;  in choose_times()
255  * Update the register file with the appropriate 3-bit state for the
264 		int n = tca->reg_file[bit] & ~mask;  in set_select()
267 		if (tca->reg_file[bit] != n) {  in set_select()
268 			tca->reg_file[bit] = n;  in set_select()
269 			tca->reg_set |= (1 << bit);  in set_select()
274 /* Update the register file with the appropriate 4-bit code for one
286 	n = tca->reg_file[reg] & ~mask;  in set_code()
288 	if (tca->reg_file[reg] != n) {  in set_code()
289 		tca->reg_file[reg] = n;  in set_code()
290 		tca->reg_set |= 1 << reg;  in set_code()
306 	tca->bank[bank].level = level;  in set_level()
315 	result = choose_times(tca->bank[bank].ontime, &c1, &c2);  in set_times()
318 	dev_dbg(&tca->client->dev,  in set_times()
321 		c2, time_codes[c2], tca->bank[bank].ontime);  in set_times()
324 	tca->bank[bank].ontime = result;  in set_times()
326 	result = choose_times(tca->bank[bank].offtime, &c1, &c2);  in set_times()
327 	dev_dbg(&tca->client->dev,  in set_times()
330 		c2, time_codes[c2], tca->bank[bank].offtime);  in set_times()
334 	tca->bank[bank].offtime = result;  in set_times()
345 	struct i2c_client *cl = tca->client;  in tca6507_work()
350 	spin_lock_irq(&tca->lock);  in tca6507_work()
351 	set = tca->reg_set;  in tca6507_work()
352 	memcpy(file, tca->reg_file, TCA6507_REG_CNT);  in tca6507_work()
353 	tca->reg_set = 0;  in tca6507_work()
354 	spin_unlock_irq(&tca->lock);  in tca6507_work()
364 	struct tca6507_chip *tca = led->chip;  in led_release()
365 	if (led->bank >= 0) {  in led_release()
366 		struct bank *b = tca->bank + led->bank;  in led_release()
367 		if (led->blink)  in led_release()
368 			b->time_use--;  in led_release()
369 		b->level_use--;  in led_release()
371 	led->blink = 0;  in led_release()
372 	led->bank = -1;  in led_release()
379 	int level = TO_LEVEL(led->led_cdev.brightness);  in led_prepare()
380 	struct tca6507_chip *tca = led->chip;  in led_prepare()
386 	led->led_cdev.brightness = TO_BRIGHT(level);  in led_prepare()
388 		set_select(tca, led->num, TCA6507_LS_LED_OFF);  in led_prepare()
392 	if (led->ontime == 0 || led->offtime == 0) {  in led_prepare()
399 		int best = -1;/* full-on */  in led_prepare()
400 		int diff = 15-level;  in led_prepare()
403 			set_select(tca, led->num, TCA6507_LS_LED_ON);  in led_prepare()
407 		for (i = MASTER; i >= BANK0; i--) {  in led_prepare()
409 			if (tca->bank[i].level == level ||  in led_prepare()
410 			    tca->bank[i].level_use == 0) {  in led_prepare()
414 			d = abs(level - tca->bank[i].level);  in led_prepare()
420 		if (best == -1) {  in led_prepare()
421 			/* Best brightness is full-on */  in led_prepare()
422 			set_select(tca, led->num, TCA6507_LS_LED_ON);  in led_prepare()
423 			led->led_cdev.brightness = LED_FULL;  in led_prepare()
427 		if (!tca->bank[best].level_use)  in led_prepare()
430 		tca->bank[best].level_use++;  in led_prepare()
431 		led->bank = best;  in led_prepare()
432 		set_select(tca, led->num, bank_source[best]);  in led_prepare()
433 		led->led_cdev.brightness = TO_BRIGHT(tca->bank[best].level);  in led_prepare()
442 	if (choose_times(led->ontime, &c1, &c2) < 0)  in led_prepare()
443 		return -EINVAL;  in led_prepare()
444 	if (choose_times(led->offtime, &c1, &c2) < 0)  in led_prepare()
445 		return -EINVAL;  in led_prepare()
448 		if (tca->bank[i].level_use == 0)  in led_prepare()
449 			/* not in use - it is ours! */  in led_prepare()
451 		if (tca->bank[i].level != level)  in led_prepare()
452 			/* Incompatible level - skip */  in led_prepare()
458 		if (tca->bank[i].time_use == 0)  in led_prepare()
459 			/* Timer not in use, and level matches - use it */  in led_prepare()
462 		if (!(tca->bank[i].on_dflt ||  in led_prepare()
463 		      led->on_dflt ||  in led_prepare()
464 		      tca->bank[i].ontime == led->ontime))  in led_prepare()
468 		if (!(tca->bank[i].off_dflt ||  in led_prepare()
469 		      led->off_dflt ||  in led_prepare()
470 		      tca->bank[i].offtime == led->offtime))  in led_prepare()
479 		/* Nothing matches - how sad */  in led_prepare()
480 		return -EINVAL;  in led_prepare()
482 	b = &tca->bank[i];  in led_prepare()
483 	if (b->level_use == 0)  in led_prepare()
485 	b->level_use++;  in led_prepare()
486 	led->bank = i;  in led_prepare()
488 	if (b->on_dflt ||  in led_prepare()
489 	    !led->on_dflt ||  in led_prepare()
490 	    b->time_use == 0) {  in led_prepare()
491 		b->ontime = led->ontime;  in led_prepare()
492 		b->on_dflt = led->on_dflt;  in led_prepare()
496 	if (b->off_dflt ||  in led_prepare()
497 	    !led->off_dflt ||  in led_prepare()
498 	    b->time_use == 0) {  in led_prepare()
499 		b->offtime = led->offtime;  in led_prepare()
500 		b->off_dflt = led->off_dflt;  in led_prepare()
507 	led->ontime = b->ontime;  in led_prepare()
508 	led->offtime = b->offtime;  in led_prepare()
510 	b->time_use++;  in led_prepare()
511 	led->blink = 1;  in led_prepare()
512 	led->led_cdev.brightness = TO_BRIGHT(b->level);  in led_prepare()
513 	set_select(tca, led->num, blink_source[i]);  in led_prepare()
519 	struct tca6507_chip *tca = led->chip;  in led_assign()
523 	spin_lock_irqsave(&tca->lock, flags);  in led_assign()
529 		 * to re-establish as steady level.  in led_assign()
531 		led->ontime = 0;  in led_assign()
532 		led->offtime = 0;  in led_assign()
535 	spin_unlock_irqrestore(&tca->lock, flags);  in led_assign()
537 	if (tca->reg_set)  in led_assign()
538 		schedule_work(&tca->work);  in led_assign()
547 	led->led_cdev.brightness = brightness;  in tca6507_brightness_set()
548 	led->ontime = 0;  in tca6507_brightness_set()
549 	led->offtime = 0;  in tca6507_brightness_set()
561 		led->on_dflt = 1;  in tca6507_blink_set()
562 	else if (delay_on != &led_cdev->blink_delay_on)  in tca6507_blink_set()
563 		led->on_dflt = 0;  in tca6507_blink_set()
564 	led->ontime = *delay_on;  in tca6507_blink_set()
567 		led->off_dflt = 1;  in tca6507_blink_set()
568 	else if (delay_off != &led_cdev->blink_delay_off)  in tca6507_blink_set()
569 		led->off_dflt = 0;  in tca6507_blink_set()
570 	led->offtime = *delay_off;  in tca6507_blink_set()
572 	if (led->ontime == 0)  in tca6507_blink_set()
573 		led->ontime = 512;  in tca6507_blink_set()
574 	if (led->offtime == 0)  in tca6507_blink_set()
575 		led->offtime = 512;  in tca6507_blink_set()
577 	if (led->led_cdev.brightness == LED_OFF)  in tca6507_blink_set()
578 		led->led_cdev.brightness = LED_FULL;  in tca6507_blink_set()
580 		led->ontime = 0;  in tca6507_blink_set()
581 		led->offtime = 0;  in tca6507_blink_set()
582 		led->led_cdev.brightness = LED_OFF;  in tca6507_blink_set()
583 		return -EINVAL;  in tca6507_blink_set()
585 	*delay_on = led->ontime;  in tca6507_blink_set()
586 	*delay_off = led->offtime;  in tca6507_blink_set()
597 	spin_lock_irqsave(&tca->lock, flags);  in tca6507_gpio_set_value()
602 	set_select(tca, tca->gpio_map[offset],  in tca6507_gpio_set_value()
604 	spin_unlock_irqrestore(&tca->lock, flags);  in tca6507_gpio_set_value()
605 	if (tca->reg_set)  in tca6507_gpio_set_value()
606 		schedule_work(&tca->work);  in tca6507_gpio_set_value()
625 		if (pdata->leds.leds[i].name && pdata->leds.leds[i].flags) {  in tca6507_probe_gpios()
627 			tca->gpio_map[gpios] = i;  in tca6507_probe_gpios()
634 	tca->gpio.label = "gpio-tca6507";  in tca6507_probe_gpios()
635 	tca->gpio.ngpio = gpios;  in tca6507_probe_gpios()
636 	tca->gpio.base = -1;  in tca6507_probe_gpios()
637 	tca->gpio.owner = THIS_MODULE;  in tca6507_probe_gpios()
638 	tca->gpio.direction_output = tca6507_gpio_direction_output;  in tca6507_probe_gpios()
639 	tca->gpio.set = tca6507_gpio_set_value;  in tca6507_probe_gpios()
640 	tca->gpio.parent = dev;  in tca6507_probe_gpios()
641 	err = devm_gpiochip_add_data(dev, &tca->gpio, tca);  in tca6507_probe_gpios()
643 		tca->gpio.ngpio = 0;  in tca6507_probe_gpios()
666 		return ERR_PTR(-ENODEV);  in tca6507_led_dt_init()
671 		return ERR_PTR(-ENOMEM);  in tca6507_led_dt_init()
681 		if (fwnode_property_read_string(child, "linux,default-trigger",  in tca6507_led_dt_init()
691 			return ERR_PTR(ret ? : -EINVAL);  in tca6507_led_dt_init()
699 		return ERR_PTR(-ENOMEM);  in tca6507_led_dt_init()
701 	pdata->leds.leds = tca_leds;  in tca6507_led_dt_init()
702 	pdata->leds.num_leds = NUM_LEDS;  in tca6507_led_dt_init()
715 	struct device *dev = &client->dev;  in tca6507_probe()
722 	adapter = client->adapter;  in tca6507_probe()
725 		return -EIO;  in tca6507_probe()
729 		dev_err(dev, "Need %d entries in platform-data list\n", NUM_LEDS);  in tca6507_probe()
734 		return -ENOMEM;  in tca6507_probe()
736 	tca->client = client;  in tca6507_probe()
737 	INIT_WORK(&tca->work, tca6507_work);  in tca6507_probe()
738 	spin_lock_init(&tca->lock);  in tca6507_probe()
742 		struct tca6507_led *l = tca->leds + i;  in tca6507_probe()
744 		l->chip = tca;  in tca6507_probe()
745 		l->num = i;  in tca6507_probe()
746 		if (pdata->leds.leds[i].name && !pdata->leds.leds[i].flags) {  in tca6507_probe()
747 			l->led_cdev.name = pdata->leds.leds[i].name;  in tca6507_probe()
748 			l->led_cdev.default_trigger  in tca6507_probe()
749 				= pdata->leds.leds[i].default_trigger;  in tca6507_probe()
750 			l->led_cdev.brightness_set = tca6507_brightness_set;  in tca6507_probe()
751 			l->led_cdev.blink_set = tca6507_blink_set;  in tca6507_probe()
752 			l->bank = -1;  in tca6507_probe()
753 			err = devm_led_classdev_register(dev, &l->led_cdev);  in tca6507_probe()
761 	/* set all registers to known state - zero */  in tca6507_probe()
762 	tca->reg_set = 0x7f;  in tca6507_probe()
763 	schedule_work(&tca->work);  in tca6507_probe()
772 	cancel_work_sync(&tca->work);  in tca6507_remove()
777 		.name    = "leds-tca6507",