xref: /linux/drivers/leds/leds-pca9532.c (revision bba2c3615bd6cfee7456d1130f2e6b01b3f4e9ba)
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 	{ .name = "pca9530", .driver_data = pca9530 },
71 	{ .name = "pca9531", .driver_data = pca9531 },
72 	{ .name = "pca9532", .driver_data = pca9532 },
73 	{ .name = "pca9533", .driver_data = 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 (led->state == PCA9532_PWM1) {
188 		return 0; /* Non-zero brightness shall not stop HW blinking */
189 	} else if (value == LED_FULL) {
190 		led->state = PCA9532_ON;
191 	} else {
192 		led->state = PCA9532_PWM0; /* Thecus: hardcode one pwm */
193 		err = pca9532_calcpwm(led->client, PCA9532_PWM_ID_0, 0, value);
194 		if (err)
195 			return err;
196 	}
197 	if (led->state == PCA9532_PWM0)
198 		pca9532_setpwm(led->client, PCA9532_PWM_ID_0);
199 	pca9532_setled(led);
200 	return err;
201 }
202 
203 static int pca9532_update_hw_blink(struct pca9532_led *led,
204 				   unsigned long delay_on, unsigned long delay_off)
205 {
206 	struct pca9532_data *data = i2c_get_clientdata(led->client);
207 	unsigned int psc;
208 	int i;
209 
210 	/* Look for others LEDs that already use PWM1 */
211 	for (i = 0; i < data->chip_info->num_leds; i++) {
212 		struct pca9532_led *other = &data->leds[i];
213 
214 		if (other == led)
215 			continue;
216 
217 		if (other->state == PCA9532_PWM1) {
218 			if (other->ldev.blink_delay_on != delay_on ||
219 			    other->ldev.blink_delay_off != delay_off) {
220 				/* HW can handle only one blink configuration at a time */
221 				return -EINVAL;
222 			}
223 		}
224 	}
225 
226 	psc = ((delay_on + delay_off) * PCA9532_PWM_PERIOD_DIV - 1) / 1000;
227 	if (psc > U8_MAX) {
228 		/* Blink period too long to be handled by hardware */
229 		return -EINVAL;
230 	}
231 
232 	led->state = PCA9532_PWM1;
233 	data->psc[PCA9532_PWM_ID_1] = psc;
234 	data->pwm[PCA9532_PWM_ID_1] = (delay_on * PCA9532_PWM_DUTY_DIV) / (delay_on + delay_off);
235 
236 	return pca9532_setpwm(data->client, PCA9532_PWM_ID_1);
237 }
238 
239 static int pca9532_set_blink(struct led_classdev *led_cdev,
240 	unsigned long *delay_on, unsigned long *delay_off)
241 {
242 	struct pca9532_led *led = ldev_to_led(led_cdev);
243 	struct i2c_client *client = led->client;
244 	struct pca9532_data *data = i2c_get_clientdata(client);
245 	int err;
246 
247 	if (!data->hw_blink)
248 		return -EINVAL;
249 
250 	if (*delay_on == 0 && *delay_off == 0) {
251 		/* led subsystem ask us for a blink rate */
252 		*delay_on = 500;
253 		*delay_off = 500;
254 	}
255 
256 	err = pca9532_update_hw_blink(led, *delay_on, *delay_off);
257 	if (err)
258 		return err;
259 
260 	pca9532_setled(led);
261 
262 	return 0;
263 }
264 
265 static int pca9532_event(struct input_dev *dev, unsigned int type,
266 	unsigned int code, int value)
267 {
268 	struct pca9532_data *data = input_get_drvdata(dev);
269 
270 	if (!(type == EV_SND && (code == SND_BELL || code == SND_TONE)))
271 		return -1;
272 
273 	/* XXX: allow different kind of beeps with psc/pwm modifications */
274 	if (value > 1 && value < 32767)
275 		data->pwm[PCA9532_PWM_ID_1] = 127;
276 	else
277 		data->pwm[PCA9532_PWM_ID_1] = 0;
278 
279 	schedule_work(&data->work);
280 
281 	return 0;
282 }
283 
284 static void pca9532_input_work(struct work_struct *work)
285 {
286 	struct pca9532_data *data =
287 		container_of(work, struct pca9532_data, work);
288 	u8 maxleds = data->chip_info->num_leds;
289 
290 	mutex_lock(&data->update_lock);
291 	i2c_smbus_write_byte_data(data->client, PCA9532_REG_PWM(maxleds, 1),
292 		data->pwm[PCA9532_PWM_ID_1]);
293 	mutex_unlock(&data->update_lock);
294 }
295 
296 static enum pca9532_state pca9532_getled(struct pca9532_led *led)
297 {
298 	struct i2c_client *client = led->client;
299 	struct pca9532_data *data = i2c_get_clientdata(client);
300 	u8 maxleds = data->chip_info->num_leds;
301 	char reg;
302 	enum pca9532_state ret;
303 
304 	mutex_lock(&data->update_lock);
305 	reg = i2c_smbus_read_byte_data(client, LED_REG(maxleds, led->id));
306 	ret = (reg & LED_MASK(led->id)) >> LED_SHIFT(led->id);
307 	mutex_unlock(&data->update_lock);
308 	return ret;
309 }
310 
311 #ifdef CONFIG_LEDS_PCA9532_GPIO
312 static int pca9532_gpio_request_pin(struct gpio_chip *gc, unsigned offset)
313 {
314 	struct pca9532_data *data = gpiochip_get_data(gc);
315 	struct pca9532_led *led = &data->leds[offset];
316 
317 	if (led->type == PCA9532_TYPE_GPIO)
318 		return 0;
319 
320 	return -EBUSY;
321 }
322 
323 static int pca9532_gpio_set_value(struct gpio_chip *gc, unsigned int offset,
324 				  int val)
325 {
326 	struct pca9532_data *data = gpiochip_get_data(gc);
327 	struct pca9532_led *led = &data->leds[offset];
328 
329 	if (val)
330 		led->state = PCA9532_ON;
331 	else
332 		led->state = PCA9532_OFF;
333 
334 	pca9532_setled(led);
335 
336 	return 0;
337 }
338 
339 static int pca9532_gpio_get_value(struct gpio_chip *gc, unsigned offset)
340 {
341 	struct pca9532_data *data = gpiochip_get_data(gc);
342 	unsigned char reg;
343 
344 	reg = i2c_smbus_read_byte_data(data->client, PCA9532_REG_INPUT(offset));
345 
346 	return !!(reg & (1 << (offset % 8)));
347 }
348 
349 static int pca9532_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
350 {
351 	/* To use as input ensure pin is not driven */
352 	pca9532_gpio_set_value(gc, offset, 0);
353 
354 	return 0;
355 }
356 
357 static int pca9532_gpio_direction_output(struct gpio_chip *gc, unsigned offset, int val)
358 {
359 	return pca9532_gpio_set_value(gc, offset, val);
360 }
361 #endif /* CONFIG_LEDS_PCA9532_GPIO */
362 
363 static void pca9532_destroy_devices(struct pca9532_data *data, int n_devs)
364 {
365 	int i = n_devs;
366 
367 	while (--i >= 0) {
368 		switch (data->leds[i].type) {
369 		case PCA9532_TYPE_NONE:
370 		case PCA9532_TYPE_GPIO:
371 			break;
372 		case PCA9532_TYPE_LED:
373 			led_classdev_unregister(&data->leds[i].ldev);
374 			break;
375 		case PCA9532_TYPE_N2100_BEEP:
376 			if (data->idev != NULL) {
377 				cancel_work_sync(&data->work);
378 				data->idev = NULL;
379 			}
380 			break;
381 		}
382 	}
383 
384 #ifdef CONFIG_LEDS_PCA9532_GPIO
385 	if (data->gpio.parent)
386 		gpiochip_remove(&data->gpio);
387 #endif
388 }
389 
390 static int pca9532_configure(struct i2c_client *client,
391 	struct pca9532_data *data, struct pca9532_platform_data *pdata)
392 {
393 	int i, err = 0;
394 	int gpios = 0;
395 	u8 maxleds = data->chip_info->num_leds;
396 
397 	for (i = 0; i < 2; i++)	{
398 		data->pwm[i] = pdata->pwm[i];
399 		data->psc[i] = pdata->psc[i];
400 		i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(maxleds, i),
401 			data->pwm[i]);
402 		i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(maxleds, i),
403 			data->psc[i]);
404 	}
405 
406 	data->hw_blink = true;
407 	for (i = 0; i < data->chip_info->num_leds; i++) {
408 		struct pca9532_led *led = &data->leds[i];
409 		struct pca9532_led *pled = &pdata->leds[i];
410 		led->client = client;
411 		led->id = i;
412 		led->type = pled->type;
413 		switch (led->type) {
414 		case PCA9532_TYPE_NONE:
415 			break;
416 		case PCA9532_TYPE_GPIO:
417 			gpios++;
418 			break;
419 		case PCA9532_TYPE_LED:
420 			if (pled->state == PCA9532_KEEP)
421 				led->state = pca9532_getled(led);
422 			else
423 				led->state = pled->state;
424 			led->name = pled->name;
425 			led->ldev.name = led->name;
426 			led->ldev.default_trigger = pled->default_trigger;
427 			led->ldev.brightness = LED_OFF;
428 			led->ldev.brightness_set_blocking =
429 						pca9532_set_brightness;
430 			led->ldev.blink_set = pca9532_set_blink;
431 			err = led_classdev_register(&client->dev, &led->ldev);
432 			if (err < 0) {
433 				dev_err(&client->dev,
434 					"couldn't register LED %s\n",
435 					led->name);
436 				goto exit;
437 			}
438 			pca9532_setled(led);
439 			break;
440 		case PCA9532_TYPE_N2100_BEEP:
441 			/* PWM1 is reserved for beeper so blink will not use hardware */
442 			data->hw_blink = false;
443 			BUG_ON(data->idev);
444 			led->state = PCA9532_PWM1;
445 			pca9532_setled(led);
446 			data->idev = devm_input_allocate_device(&client->dev);
447 			if (data->idev == NULL) {
448 				err = -ENOMEM;
449 				goto exit;
450 			}
451 			data->idev->name = pled->name;
452 			data->idev->phys = "i2c/pca9532";
453 			data->idev->id.bustype = BUS_HOST;
454 			data->idev->id.vendor = 0x001f;
455 			data->idev->id.product = 0x0001;
456 			data->idev->id.version = 0x0100;
457 			data->idev->evbit[0] = BIT_MASK(EV_SND);
458 			data->idev->sndbit[0] = BIT_MASK(SND_BELL) |
459 						BIT_MASK(SND_TONE);
460 			data->idev->event = pca9532_event;
461 			input_set_drvdata(data->idev, data);
462 			INIT_WORK(&data->work, pca9532_input_work);
463 			err = input_register_device(data->idev);
464 			if (err) {
465 				cancel_work_sync(&data->work);
466 				data->idev = NULL;
467 				goto exit;
468 			}
469 			break;
470 		}
471 	}
472 
473 #ifdef CONFIG_LEDS_PCA9532_GPIO
474 	if (gpios) {
475 		data->gpio.label = "gpio-pca9532";
476 		data->gpio.direction_input = pca9532_gpio_direction_input;
477 		data->gpio.direction_output = pca9532_gpio_direction_output;
478 		data->gpio.set = pca9532_gpio_set_value;
479 		data->gpio.get = pca9532_gpio_get_value;
480 		data->gpio.request = pca9532_gpio_request_pin;
481 		data->gpio.can_sleep = 1;
482 		data->gpio.base = pdata->gpio_base;
483 		data->gpio.ngpio = data->chip_info->num_leds;
484 		data->gpio.parent = &client->dev;
485 		data->gpio.owner = THIS_MODULE;
486 
487 		err = gpiochip_add_data(&data->gpio, data);
488 		if (err) {
489 			/* Use data->gpio.dev as a flag for freeing gpiochip */
490 			data->gpio.parent = NULL;
491 			dev_warn(&client->dev, "could not add gpiochip\n");
492 		} else {
493 			dev_info(&client->dev, "gpios %i...%i\n",
494 				data->gpio.base, data->gpio.base +
495 				data->gpio.ngpio - 1);
496 		}
497 	}
498 #endif
499 
500 	return 0;
501 
502 exit:
503 	pca9532_destroy_devices(data, i);
504 	return err;
505 }
506 
507 static struct pca9532_platform_data *
508 pca9532_of_populate_pdata(struct device *dev, struct device_node *np)
509 {
510 	struct pca9532_platform_data *pdata;
511 	int devid, maxleds;
512 	int i = 0;
513 	const char *state;
514 
515 	devid = (int)(uintptr_t)of_device_get_match_data(dev);
516 	maxleds = pca9532_chip_info_tbl[devid].num_leds;
517 
518 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
519 	if (!pdata)
520 		return ERR_PTR(-ENOMEM);
521 
522 	pdata->gpio_base = -1;
523 
524 	of_property_read_u8_array(np, "nxp,pwm", &pdata->pwm[PCA9532_PWM_ID_0],
525 				  ARRAY_SIZE(pdata->pwm));
526 	of_property_read_u8_array(np, "nxp,psc", &pdata->psc[PCA9532_PWM_ID_0],
527 				  ARRAY_SIZE(pdata->psc));
528 
529 	for_each_available_child_of_node_scoped(np, child) {
530 		if (of_property_read_string(child, "label",
531 					    &pdata->leds[i].name))
532 			pdata->leds[i].name = child->name;
533 		of_property_read_u32(child, "type", &pdata->leds[i].type);
534 		of_property_read_string(child, "linux,default-trigger",
535 					&pdata->leds[i].default_trigger);
536 		if (!of_property_read_string(child, "default-state", &state)) {
537 			if (!strcmp(state, "on"))
538 				pdata->leds[i].state = PCA9532_ON;
539 			else if (!strcmp(state, "keep"))
540 				pdata->leds[i].state = PCA9532_KEEP;
541 		}
542 		if (++i >= maxleds)
543 			break;
544 	}
545 
546 	return pdata;
547 }
548 
549 static int pca9532_probe(struct i2c_client *client)
550 {
551 	const struct i2c_device_id *id = i2c_client_get_device_id(client);
552 	int devid;
553 	struct pca9532_data *data = i2c_get_clientdata(client);
554 	struct pca9532_platform_data *pca9532_pdata =
555 			dev_get_platdata(&client->dev);
556 	struct device_node *np = dev_of_node(&client->dev);
557 
558 	if (!pca9532_pdata) {
559 		if (np) {
560 			pca9532_pdata =
561 				pca9532_of_populate_pdata(&client->dev, np);
562 			if (IS_ERR(pca9532_pdata))
563 				return PTR_ERR(pca9532_pdata);
564 		} else {
565 			dev_err(&client->dev, "no platform data\n");
566 			return -EINVAL;
567 		}
568 		devid = (int)(uintptr_t)of_device_get_match_data(&client->dev);
569 	} else {
570 		devid = id->driver_data;
571 	}
572 
573 	if (!i2c_check_functionality(client->adapter,
574 		I2C_FUNC_SMBUS_BYTE_DATA))
575 		return -EIO;
576 
577 	data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
578 	if (!data)
579 		return -ENOMEM;
580 
581 	data->chip_info = &pca9532_chip_info_tbl[devid];
582 
583 	dev_info(&client->dev, "setting platform data\n");
584 	i2c_set_clientdata(client, data);
585 	data->client = client;
586 	mutex_init(&data->update_lock);
587 
588 	return pca9532_configure(client, data, pca9532_pdata);
589 }
590 
591 static void pca9532_remove(struct i2c_client *client)
592 {
593 	struct pca9532_data *data = i2c_get_clientdata(client);
594 
595 	pca9532_destroy_devices(data, data->chip_info->num_leds);
596 }
597 
598 module_i2c_driver(pca9532_driver);
599 
600 MODULE_AUTHOR("Riku Voipio");
601 MODULE_LICENSE("GPL");
602 MODULE_DESCRIPTION("PCA 9532 LED dimmer");
603