xref: /linux/drivers/leds/leds-pca9532.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * pca9532.c - 16-bit Led dimmer
4  *
5  * Copyright (C) 2011 Jan Weitzel
6  * Copyright (C) 2008 Riku Voipio
7  *
8  * Datasheet: http://www.nxp.com/documents/data_sheet/PCA9532.pdf
9  */
10 
11 #include <linux/module.h>
12 #include <linux/i2c.h>
13 #include <linux/slab.h>
14 #include <linux/leds.h>
15 #include <linux/input.h>
16 #include <linux/mutex.h>
17 #include <linux/workqueue.h>
18 #include <linux/leds-pca9532.h>
19 #include <linux/gpio/driver.h>
20 #include <linux/of.h>
21 
22 /* m =  num_leds*/
23 #define PCA9532_REG_INPUT(i)	((i) >> 3)
24 #define PCA9532_REG_OFFSET(m)	((m) >> 4)
25 #define PCA9532_REG_PSC(m, i)	(PCA9532_REG_OFFSET(m) + 0x1 + (i) * 2)
26 #define PCA9532_REG_PWM(m, i)	(PCA9532_REG_OFFSET(m) + 0x2 + (i) * 2)
27 #define LED_REG(m, led)		(PCA9532_REG_OFFSET(m) + 0x5 + (led >> 2))
28 #define LED_NUM(led)		(led & 0x3)
29 #define LED_SHIFT(led)		(LED_NUM(led) * 2)
30 #define LED_MASK(led)		(0x3 << LED_SHIFT(led))
31 
32 #define PCA9532_PWM_PERIOD_DIV	152
33 #define PCA9532_PWM_DUTY_DIV	256
34 
35 #define ldev_to_led(c)       container_of(c, struct pca9532_led, ldev)
36 
37 struct pca9532_chip_info {
38 	u8	num_leds;
39 };
40 
41 struct pca9532_data {
42 	struct i2c_client *client;
43 	struct pca9532_led leds[16];
44 	struct mutex update_lock;
45 	struct input_dev *idev;
46 	struct work_struct work;
47 #ifdef CONFIG_LEDS_PCA9532_GPIO
48 	struct gpio_chip gpio;
49 #endif
50 	const struct pca9532_chip_info *chip_info;
51 
52 #define PCA9532_PWM_ID_0	0
53 #define PCA9532_PWM_ID_1	1
54 	u8 pwm[2];
55 	u8 psc[2];
56 	bool hw_blink;
57 };
58 
59 static int pca9532_probe(struct i2c_client *client);
60 static void pca9532_remove(struct i2c_client *client);
61 
62 enum {
63 	pca9530,
64 	pca9531,
65 	pca9532,
66 	pca9533,
67 };
68 
69 static const struct i2c_device_id pca9532_id[] = {
70 	{ "pca9530", pca9530 },
71 	{ "pca9531", pca9531 },
72 	{ "pca9532", pca9532 },
73 	{ "pca9533", pca9533 },
74 	{ }
75 };
76 
77 MODULE_DEVICE_TABLE(i2c, pca9532_id);
78 
79 static const struct pca9532_chip_info pca9532_chip_info_tbl[] = {
80 	[pca9530] = {
81 		.num_leds = 2,
82 	},
83 	[pca9531] = {
84 		.num_leds = 8,
85 	},
86 	[pca9532] = {
87 		.num_leds = 16,
88 	},
89 	[pca9533] = {
90 		.num_leds = 4,
91 	},
92 };
93 
94 #ifdef CONFIG_OF
95 static const struct of_device_id of_pca9532_leds_match[] = {
96 	{ .compatible = "nxp,pca9530", .data = (void *)pca9530 },
97 	{ .compatible = "nxp,pca9531", .data = (void *)pca9531 },
98 	{ .compatible = "nxp,pca9532", .data = (void *)pca9532 },
99 	{ .compatible = "nxp,pca9533", .data = (void *)pca9533 },
100 	{},
101 };
102 
103 MODULE_DEVICE_TABLE(of, of_pca9532_leds_match);
104 #endif
105 
106 static struct i2c_driver pca9532_driver = {
107 	.driver = {
108 		.name = "leds-pca953x",
109 		.of_match_table = of_match_ptr(of_pca9532_leds_match),
110 	},
111 	.probe = pca9532_probe,
112 	.remove = pca9532_remove,
113 	.id_table = pca9532_id,
114 };
115 
116 /* We have two pwm/blinkers, but 16 possible leds to drive. Additionally,
117  * the clever Thecus people are using one pwm to drive the beeper. So,
118  * as a compromise we average one pwm to the values requested by all
119  * leds that are not ON/OFF.
120  * */
121 static int pca9532_calcpwm(struct i2c_client *client, int pwm, int blink,
122 	enum led_brightness value)
123 {
124 	int a = 0, b = 0, i = 0;
125 	struct pca9532_data *data = i2c_get_clientdata(client);
126 	for (i = 0; i < data->chip_info->num_leds; i++) {
127 		if (data->leds[i].type == PCA9532_TYPE_LED &&
128 			data->leds[i].state == PCA9532_PWM0+pwm) {
129 				a++;
130 				b += data->leds[i].ldev.brightness;
131 		}
132 	}
133 	if (a == 0) {
134 		dev_err(&client->dev,
135 		"fear of division by zero %d/%d, wanted %d\n",
136 			b, a, value);
137 		return -EINVAL;
138 	}
139 	b = b/a;
140 	if (b > 0xFF)
141 		return -EINVAL;
142 	data->pwm[pwm] = b;
143 	data->psc[pwm] = blink;
144 	return 0;
145 }
146 
147 static int pca9532_setpwm(struct i2c_client *client, int pwm)
148 {
149 	struct pca9532_data *data = i2c_get_clientdata(client);
150 	u8 maxleds = data->chip_info->num_leds;
151 
152 	mutex_lock(&data->update_lock);
153 	i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(maxleds, pwm),
154 		data->pwm[pwm]);
155 	i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(maxleds, pwm),
156 		data->psc[pwm]);
157 	mutex_unlock(&data->update_lock);
158 	return 0;
159 }
160 
161 /* Set LED routing */
162 static void pca9532_setled(struct pca9532_led *led)
163 {
164 	struct i2c_client *client = led->client;
165 	struct pca9532_data *data = i2c_get_clientdata(client);
166 	u8 maxleds = data->chip_info->num_leds;
167 	char reg;
168 
169 	mutex_lock(&data->update_lock);
170 	reg = i2c_smbus_read_byte_data(client, LED_REG(maxleds, led->id));
171 	/* zero led bits */
172 	reg = reg & ~LED_MASK(led->id);
173 	/* set the new value */
174 	reg = reg | (led->state << LED_SHIFT(led->id));
175 	i2c_smbus_write_byte_data(client, LED_REG(maxleds, led->id), reg);
176 	mutex_unlock(&data->update_lock);
177 }
178 
179 static int pca9532_set_brightness(struct led_classdev *led_cdev,
180 	enum led_brightness value)
181 {
182 	int err = 0;
183 	struct pca9532_led *led = ldev_to_led(led_cdev);
184 
185 	if (value == LED_OFF)
186 		led->state = PCA9532_OFF;
187 	else if (value == LED_FULL)
188 		led->state = PCA9532_ON;
189 	else {
190 		led->state = PCA9532_PWM0; /* Thecus: hardcode one pwm */
191 		err = pca9532_calcpwm(led->client, PCA9532_PWM_ID_0, 0, value);
192 		if (err)
193 			return err;
194 	}
195 	if (led->state == PCA9532_PWM0)
196 		pca9532_setpwm(led->client, PCA9532_PWM_ID_0);
197 	pca9532_setled(led);
198 	return err;
199 }
200 
201 static int pca9532_update_hw_blink(struct pca9532_led *led,
202 				   unsigned long delay_on, unsigned long delay_off)
203 {
204 	struct pca9532_data *data = i2c_get_clientdata(led->client);
205 	unsigned int psc;
206 	int i;
207 
208 	/* Look for others LEDs that already use PWM1 */
209 	for (i = 0; i < data->chip_info->num_leds; i++) {
210 		struct pca9532_led *other = &data->leds[i];
211 
212 		if (other == led)
213 			continue;
214 
215 		if (other->state == PCA9532_PWM1) {
216 			if (other->ldev.blink_delay_on != delay_on ||
217 			    other->ldev.blink_delay_off != delay_off) {
218 				/* HW can handle only one blink configuration at a time */
219 				return -EINVAL;
220 			}
221 		}
222 	}
223 
224 	psc = ((delay_on + delay_off) * PCA9532_PWM_PERIOD_DIV - 1) / 1000;
225 	if (psc > U8_MAX) {
226 		/* Blink period too long to be handled by hardware */
227 		return -EINVAL;
228 	}
229 
230 	led->state = PCA9532_PWM1;
231 	data->psc[PCA9532_PWM_ID_1] = psc;
232 	data->pwm[PCA9532_PWM_ID_1] = (delay_on * PCA9532_PWM_DUTY_DIV) / (delay_on + delay_off);
233 
234 	return pca9532_setpwm(data->client, PCA9532_PWM_ID_1);
235 }
236 
237 static int pca9532_set_blink(struct led_classdev *led_cdev,
238 	unsigned long *delay_on, unsigned long *delay_off)
239 {
240 	struct pca9532_led *led = ldev_to_led(led_cdev);
241 	struct i2c_client *client = led->client;
242 	struct pca9532_data *data = i2c_get_clientdata(client);
243 	int err;
244 
245 	if (!data->hw_blink)
246 		return -EINVAL;
247 
248 	if (*delay_on == 0 && *delay_off == 0) {
249 		/* led subsystem ask us for a blink rate */
250 		*delay_on = 500;
251 		*delay_off = 500;
252 	}
253 
254 	err = pca9532_update_hw_blink(led, *delay_on, *delay_off);
255 	if (err)
256 		return err;
257 
258 	pca9532_setled(led);
259 
260 	return 0;
261 }
262 
263 static int pca9532_event(struct input_dev *dev, unsigned int type,
264 	unsigned int code, int value)
265 {
266 	struct pca9532_data *data = input_get_drvdata(dev);
267 
268 	if (!(type == EV_SND && (code == SND_BELL || code == SND_TONE)))
269 		return -1;
270 
271 	/* XXX: allow different kind of beeps with psc/pwm modifications */
272 	if (value > 1 && value < 32767)
273 		data->pwm[PCA9532_PWM_ID_1] = 127;
274 	else
275 		data->pwm[PCA9532_PWM_ID_1] = 0;
276 
277 	schedule_work(&data->work);
278 
279 	return 0;
280 }
281 
282 static void pca9532_input_work(struct work_struct *work)
283 {
284 	struct pca9532_data *data =
285 		container_of(work, struct pca9532_data, work);
286 	u8 maxleds = data->chip_info->num_leds;
287 
288 	mutex_lock(&data->update_lock);
289 	i2c_smbus_write_byte_data(data->client, PCA9532_REG_PWM(maxleds, 1),
290 		data->pwm[PCA9532_PWM_ID_1]);
291 	mutex_unlock(&data->update_lock);
292 }
293 
294 static enum pca9532_state pca9532_getled(struct pca9532_led *led)
295 {
296 	struct i2c_client *client = led->client;
297 	struct pca9532_data *data = i2c_get_clientdata(client);
298 	u8 maxleds = data->chip_info->num_leds;
299 	char reg;
300 	enum pca9532_state ret;
301 
302 	mutex_lock(&data->update_lock);
303 	reg = i2c_smbus_read_byte_data(client, LED_REG(maxleds, led->id));
304 	ret = (reg & LED_MASK(led->id)) >> LED_SHIFT(led->id);
305 	mutex_unlock(&data->update_lock);
306 	return ret;
307 }
308 
309 #ifdef CONFIG_LEDS_PCA9532_GPIO
310 static int pca9532_gpio_request_pin(struct gpio_chip *gc, unsigned offset)
311 {
312 	struct pca9532_data *data = gpiochip_get_data(gc);
313 	struct pca9532_led *led = &data->leds[offset];
314 
315 	if (led->type == PCA9532_TYPE_GPIO)
316 		return 0;
317 
318 	return -EBUSY;
319 }
320 
321 static void pca9532_gpio_set_value(struct gpio_chip *gc, unsigned offset, int val)
322 {
323 	struct pca9532_data *data = gpiochip_get_data(gc);
324 	struct pca9532_led *led = &data->leds[offset];
325 
326 	if (val)
327 		led->state = PCA9532_ON;
328 	else
329 		led->state = PCA9532_OFF;
330 
331 	pca9532_setled(led);
332 }
333 
334 static int pca9532_gpio_get_value(struct gpio_chip *gc, unsigned offset)
335 {
336 	struct pca9532_data *data = gpiochip_get_data(gc);
337 	unsigned char reg;
338 
339 	reg = i2c_smbus_read_byte_data(data->client, PCA9532_REG_INPUT(offset));
340 
341 	return !!(reg & (1 << (offset % 8)));
342 }
343 
344 static int pca9532_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
345 {
346 	/* To use as input ensure pin is not driven */
347 	pca9532_gpio_set_value(gc, offset, 0);
348 
349 	return 0;
350 }
351 
352 static int pca9532_gpio_direction_output(struct gpio_chip *gc, unsigned offset, int val)
353 {
354 	pca9532_gpio_set_value(gc, offset, val);
355 
356 	return 0;
357 }
358 #endif /* CONFIG_LEDS_PCA9532_GPIO */
359 
360 static void pca9532_destroy_devices(struct pca9532_data *data, int n_devs)
361 {
362 	int i = n_devs;
363 
364 	while (--i >= 0) {
365 		switch (data->leds[i].type) {
366 		case PCA9532_TYPE_NONE:
367 		case PCA9532_TYPE_GPIO:
368 			break;
369 		case PCA9532_TYPE_LED:
370 			led_classdev_unregister(&data->leds[i].ldev);
371 			break;
372 		case PCA9532_TYPE_N2100_BEEP:
373 			if (data->idev != NULL) {
374 				cancel_work_sync(&data->work);
375 				data->idev = NULL;
376 			}
377 			break;
378 		}
379 	}
380 
381 #ifdef CONFIG_LEDS_PCA9532_GPIO
382 	if (data->gpio.parent)
383 		gpiochip_remove(&data->gpio);
384 #endif
385 }
386 
387 static int pca9532_configure(struct i2c_client *client,
388 	struct pca9532_data *data, struct pca9532_platform_data *pdata)
389 {
390 	int i, err = 0;
391 	int gpios = 0;
392 	u8 maxleds = data->chip_info->num_leds;
393 
394 	for (i = 0; i < 2; i++)	{
395 		data->pwm[i] = pdata->pwm[i];
396 		data->psc[i] = pdata->psc[i];
397 		i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(maxleds, i),
398 			data->pwm[i]);
399 		i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(maxleds, i),
400 			data->psc[i]);
401 	}
402 
403 	data->hw_blink = true;
404 	for (i = 0; i < data->chip_info->num_leds; i++) {
405 		struct pca9532_led *led = &data->leds[i];
406 		struct pca9532_led *pled = &pdata->leds[i];
407 		led->client = client;
408 		led->id = i;
409 		led->type = pled->type;
410 		switch (led->type) {
411 		case PCA9532_TYPE_NONE:
412 			break;
413 		case PCA9532_TYPE_GPIO:
414 			gpios++;
415 			break;
416 		case PCA9532_TYPE_LED:
417 			if (pled->state == PCA9532_KEEP)
418 				led->state = pca9532_getled(led);
419 			else
420 				led->state = pled->state;
421 			led->name = pled->name;
422 			led->ldev.name = led->name;
423 			led->ldev.default_trigger = pled->default_trigger;
424 			led->ldev.brightness = LED_OFF;
425 			led->ldev.brightness_set_blocking =
426 						pca9532_set_brightness;
427 			led->ldev.blink_set = pca9532_set_blink;
428 			err = led_classdev_register(&client->dev, &led->ldev);
429 			if (err < 0) {
430 				dev_err(&client->dev,
431 					"couldn't register LED %s\n",
432 					led->name);
433 				goto exit;
434 			}
435 			pca9532_setled(led);
436 			break;
437 		case PCA9532_TYPE_N2100_BEEP:
438 			/* PWM1 is reserved for beeper so blink will not use hardware */
439 			data->hw_blink = false;
440 			BUG_ON(data->idev);
441 			led->state = PCA9532_PWM1;
442 			pca9532_setled(led);
443 			data->idev = devm_input_allocate_device(&client->dev);
444 			if (data->idev == NULL) {
445 				err = -ENOMEM;
446 				goto exit;
447 			}
448 			data->idev->name = pled->name;
449 			data->idev->phys = "i2c/pca9532";
450 			data->idev->id.bustype = BUS_HOST;
451 			data->idev->id.vendor = 0x001f;
452 			data->idev->id.product = 0x0001;
453 			data->idev->id.version = 0x0100;
454 			data->idev->evbit[0] = BIT_MASK(EV_SND);
455 			data->idev->sndbit[0] = BIT_MASK(SND_BELL) |
456 						BIT_MASK(SND_TONE);
457 			data->idev->event = pca9532_event;
458 			input_set_drvdata(data->idev, data);
459 			INIT_WORK(&data->work, pca9532_input_work);
460 			err = input_register_device(data->idev);
461 			if (err) {
462 				cancel_work_sync(&data->work);
463 				data->idev = NULL;
464 				goto exit;
465 			}
466 			break;
467 		}
468 	}
469 
470 #ifdef CONFIG_LEDS_PCA9532_GPIO
471 	if (gpios) {
472 		data->gpio.label = "gpio-pca9532";
473 		data->gpio.direction_input = pca9532_gpio_direction_input;
474 		data->gpio.direction_output = pca9532_gpio_direction_output;
475 		data->gpio.set = pca9532_gpio_set_value;
476 		data->gpio.get = pca9532_gpio_get_value;
477 		data->gpio.request = pca9532_gpio_request_pin;
478 		data->gpio.can_sleep = 1;
479 		data->gpio.base = pdata->gpio_base;
480 		data->gpio.ngpio = data->chip_info->num_leds;
481 		data->gpio.parent = &client->dev;
482 		data->gpio.owner = THIS_MODULE;
483 
484 		err = gpiochip_add_data(&data->gpio, data);
485 		if (err) {
486 			/* Use data->gpio.dev as a flag for freeing gpiochip */
487 			data->gpio.parent = NULL;
488 			dev_warn(&client->dev, "could not add gpiochip\n");
489 		} else {
490 			dev_info(&client->dev, "gpios %i...%i\n",
491 				data->gpio.base, data->gpio.base +
492 				data->gpio.ngpio - 1);
493 		}
494 	}
495 #endif
496 
497 	return 0;
498 
499 exit:
500 	pca9532_destroy_devices(data, i);
501 	return err;
502 }
503 
504 static struct pca9532_platform_data *
505 pca9532_of_populate_pdata(struct device *dev, struct device_node *np)
506 {
507 	struct pca9532_platform_data *pdata;
508 	int devid, maxleds;
509 	int i = 0;
510 	const char *state;
511 
512 	devid = (int)(uintptr_t)of_device_get_match_data(dev);
513 	maxleds = pca9532_chip_info_tbl[devid].num_leds;
514 
515 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
516 	if (!pdata)
517 		return ERR_PTR(-ENOMEM);
518 
519 	pdata->gpio_base = -1;
520 
521 	of_property_read_u8_array(np, "nxp,pwm", &pdata->pwm[PCA9532_PWM_ID_0],
522 				  ARRAY_SIZE(pdata->pwm));
523 	of_property_read_u8_array(np, "nxp,psc", &pdata->psc[PCA9532_PWM_ID_0],
524 				  ARRAY_SIZE(pdata->psc));
525 
526 	for_each_available_child_of_node_scoped(np, child) {
527 		if (of_property_read_string(child, "label",
528 					    &pdata->leds[i].name))
529 			pdata->leds[i].name = child->name;
530 		of_property_read_u32(child, "type", &pdata->leds[i].type);
531 		of_property_read_string(child, "linux,default-trigger",
532 					&pdata->leds[i].default_trigger);
533 		if (!of_property_read_string(child, "default-state", &state)) {
534 			if (!strcmp(state, "on"))
535 				pdata->leds[i].state = PCA9532_ON;
536 			else if (!strcmp(state, "keep"))
537 				pdata->leds[i].state = PCA9532_KEEP;
538 		}
539 		if (++i >= maxleds)
540 			break;
541 	}
542 
543 	return pdata;
544 }
545 
546 static int pca9532_probe(struct i2c_client *client)
547 {
548 	const struct i2c_device_id *id = i2c_client_get_device_id(client);
549 	int devid;
550 	struct pca9532_data *data = i2c_get_clientdata(client);
551 	struct pca9532_platform_data *pca9532_pdata =
552 			dev_get_platdata(&client->dev);
553 	struct device_node *np = dev_of_node(&client->dev);
554 
555 	if (!pca9532_pdata) {
556 		if (np) {
557 			pca9532_pdata =
558 				pca9532_of_populate_pdata(&client->dev, np);
559 			if (IS_ERR(pca9532_pdata))
560 				return PTR_ERR(pca9532_pdata);
561 		} else {
562 			dev_err(&client->dev, "no platform data\n");
563 			return -EINVAL;
564 		}
565 		devid = (int)(uintptr_t)of_device_get_match_data(&client->dev);
566 	} else {
567 		devid = id->driver_data;
568 	}
569 
570 	if (!i2c_check_functionality(client->adapter,
571 		I2C_FUNC_SMBUS_BYTE_DATA))
572 		return -EIO;
573 
574 	data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
575 	if (!data)
576 		return -ENOMEM;
577 
578 	data->chip_info = &pca9532_chip_info_tbl[devid];
579 
580 	dev_info(&client->dev, "setting platform data\n");
581 	i2c_set_clientdata(client, data);
582 	data->client = client;
583 	mutex_init(&data->update_lock);
584 
585 	return pca9532_configure(client, data, pca9532_pdata);
586 }
587 
588 static void pca9532_remove(struct i2c_client *client)
589 {
590 	struct pca9532_data *data = i2c_get_clientdata(client);
591 
592 	pca9532_destroy_devices(data, data->chip_info->num_leds);
593 }
594 
595 module_i2c_driver(pca9532_driver);
596 
597 MODULE_AUTHOR("Riku Voipio");
598 MODULE_LICENSE("GPL");
599 MODULE_DESCRIPTION("PCA 9532 LED dimmer");
600