xref: /openbmc/linux/drivers/leds/leds-pca9532.c (revision 82b5d164)
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 #include <linux/of_device.h>
22 
23 /* m =  num_leds*/
24 #define PCA9532_REG_INPUT(i)	((i) >> 3)
25 #define PCA9532_REG_OFFSET(m)	((m) >> 4)
26 #define PCA9532_REG_PSC(m, i)	(PCA9532_REG_OFFSET(m) + 0x1 + (i) * 2)
27 #define PCA9532_REG_PWM(m, i)	(PCA9532_REG_OFFSET(m) + 0x2 + (i) * 2)
28 #define LED_REG(m, led)		(PCA9532_REG_OFFSET(m) + 0x5 + (led >> 2))
29 #define LED_NUM(led)		(led & 0x3)
30 
31 #define ldev_to_led(c)       container_of(c, struct pca9532_led, ldev)
32 
33 struct pca9532_chip_info {
34 	u8	num_leds;
35 };
36 
37 struct pca9532_data {
38 	struct i2c_client *client;
39 	struct pca9532_led leds[16];
40 	struct mutex update_lock;
41 	struct input_dev *idev;
42 	struct work_struct work;
43 #ifdef CONFIG_LEDS_PCA9532_GPIO
44 	struct gpio_chip gpio;
45 #endif
46 	const struct pca9532_chip_info *chip_info;
47 	u8 pwm[2];
48 	u8 psc[2];
49 };
50 
51 static int pca9532_probe(struct i2c_client *client,
52 	const struct i2c_device_id *id);
53 static int pca9532_remove(struct i2c_client *client);
54 
55 enum {
56 	pca9530,
57 	pca9531,
58 	pca9532,
59 	pca9533,
60 };
61 
62 static const struct i2c_device_id pca9532_id[] = {
63 	{ "pca9530", pca9530 },
64 	{ "pca9531", pca9531 },
65 	{ "pca9532", pca9532 },
66 	{ "pca9533", pca9533 },
67 	{ }
68 };
69 
70 MODULE_DEVICE_TABLE(i2c, pca9532_id);
71 
72 static const struct pca9532_chip_info pca9532_chip_info_tbl[] = {
73 	[pca9530] = {
74 		.num_leds = 2,
75 	},
76 	[pca9531] = {
77 		.num_leds = 8,
78 	},
79 	[pca9532] = {
80 		.num_leds = 16,
81 	},
82 	[pca9533] = {
83 		.num_leds = 4,
84 	},
85 };
86 
87 #ifdef CONFIG_OF
88 static const struct of_device_id of_pca9532_leds_match[] = {
89 	{ .compatible = "nxp,pca9530", .data = (void *)pca9530 },
90 	{ .compatible = "nxp,pca9531", .data = (void *)pca9531 },
91 	{ .compatible = "nxp,pca9532", .data = (void *)pca9532 },
92 	{ .compatible = "nxp,pca9533", .data = (void *)pca9533 },
93 	{},
94 };
95 
96 MODULE_DEVICE_TABLE(of, of_pca9532_leds_match);
97 #endif
98 
99 static struct i2c_driver pca9532_driver = {
100 	.driver = {
101 		.name = "leds-pca953x",
102 		.of_match_table = of_match_ptr(of_pca9532_leds_match),
103 	},
104 	.probe = pca9532_probe,
105 	.remove = pca9532_remove,
106 	.id_table = pca9532_id,
107 };
108 
109 /* We have two pwm/blinkers, but 16 possible leds to drive. Additionally,
110  * the clever Thecus people are using one pwm to drive the beeper. So,
111  * as a compromise we average one pwm to the values requested by all
112  * leds that are not ON/OFF.
113  * */
114 static int pca9532_calcpwm(struct i2c_client *client, int pwm, int blink,
115 	enum led_brightness value)
116 {
117 	int a = 0, b = 0, i = 0;
118 	struct pca9532_data *data = i2c_get_clientdata(client);
119 	for (i = 0; i < data->chip_info->num_leds; i++) {
120 		if (data->leds[i].type == PCA9532_TYPE_LED &&
121 			data->leds[i].state == PCA9532_PWM0+pwm) {
122 				a++;
123 				b += data->leds[i].ldev.brightness;
124 		}
125 	}
126 	if (a == 0) {
127 		dev_err(&client->dev,
128 		"fear of division by zero %d/%d, wanted %d\n",
129 			b, a, value);
130 		return -EINVAL;
131 	}
132 	b = b/a;
133 	if (b > 0xFF)
134 		return -EINVAL;
135 	data->pwm[pwm] = b;
136 	data->psc[pwm] = blink;
137 	return 0;
138 }
139 
140 static int pca9532_setpwm(struct i2c_client *client, int pwm)
141 {
142 	struct pca9532_data *data = i2c_get_clientdata(client);
143 	u8 maxleds = data->chip_info->num_leds;
144 
145 	mutex_lock(&data->update_lock);
146 	i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(maxleds, pwm),
147 		data->pwm[pwm]);
148 	i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(maxleds, pwm),
149 		data->psc[pwm]);
150 	mutex_unlock(&data->update_lock);
151 	return 0;
152 }
153 
154 /* Set LED routing */
155 static void pca9532_setled(struct pca9532_led *led)
156 {
157 	struct i2c_client *client = led->client;
158 	struct pca9532_data *data = i2c_get_clientdata(client);
159 	u8 maxleds = data->chip_info->num_leds;
160 	char reg;
161 
162 	mutex_lock(&data->update_lock);
163 	reg = i2c_smbus_read_byte_data(client, LED_REG(maxleds, led->id));
164 	/* zero led bits */
165 	reg = reg & ~(0x3<<LED_NUM(led->id)*2);
166 	/* set the new value */
167 	reg = reg | (led->state << LED_NUM(led->id)*2);
168 	i2c_smbus_write_byte_data(client, LED_REG(maxleds, led->id), reg);
169 	mutex_unlock(&data->update_lock);
170 }
171 
172 static int pca9532_set_brightness(struct led_classdev *led_cdev,
173 	enum led_brightness value)
174 {
175 	int err = 0;
176 	struct pca9532_led *led = ldev_to_led(led_cdev);
177 
178 	if (value == LED_OFF)
179 		led->state = PCA9532_OFF;
180 	else if (value == LED_FULL)
181 		led->state = PCA9532_ON;
182 	else {
183 		led->state = PCA9532_PWM0; /* Thecus: hardcode one pwm */
184 		err = pca9532_calcpwm(led->client, 0, 0, value);
185 		if (err)
186 			return err;
187 	}
188 	if (led->state == PCA9532_PWM0)
189 		pca9532_setpwm(led->client, 0);
190 	pca9532_setled(led);
191 	return err;
192 }
193 
194 static int pca9532_set_blink(struct led_classdev *led_cdev,
195 	unsigned long *delay_on, unsigned long *delay_off)
196 {
197 	struct pca9532_led *led = ldev_to_led(led_cdev);
198 	struct i2c_client *client = led->client;
199 	int psc;
200 	int err = 0;
201 
202 	if (*delay_on == 0 && *delay_off == 0) {
203 		/* led subsystem ask us for a blink rate */
204 		*delay_on = 1000;
205 		*delay_off = 1000;
206 	}
207 	if (*delay_on != *delay_off || *delay_on > 1690 || *delay_on < 6)
208 		return -EINVAL;
209 
210 	/* Thecus specific: only use PSC/PWM 0 */
211 	psc = (*delay_on * 152-1)/1000;
212 	err = pca9532_calcpwm(client, 0, psc, led_cdev->brightness);
213 	if (err)
214 		return err;
215 	if (led->state == PCA9532_PWM0)
216 		pca9532_setpwm(led->client, 0);
217 	pca9532_setled(led);
218 
219 	return 0;
220 }
221 
222 static int pca9532_event(struct input_dev *dev, unsigned int type,
223 	unsigned int code, int value)
224 {
225 	struct pca9532_data *data = input_get_drvdata(dev);
226 
227 	if (!(type == EV_SND && (code == SND_BELL || code == SND_TONE)))
228 		return -1;
229 
230 	/* XXX: allow different kind of beeps with psc/pwm modifications */
231 	if (value > 1 && value < 32767)
232 		data->pwm[1] = 127;
233 	else
234 		data->pwm[1] = 0;
235 
236 	schedule_work(&data->work);
237 
238 	return 0;
239 }
240 
241 static void pca9532_input_work(struct work_struct *work)
242 {
243 	struct pca9532_data *data =
244 		container_of(work, struct pca9532_data, work);
245 	u8 maxleds = data->chip_info->num_leds;
246 
247 	mutex_lock(&data->update_lock);
248 	i2c_smbus_write_byte_data(data->client, PCA9532_REG_PWM(maxleds, 1),
249 		data->pwm[1]);
250 	mutex_unlock(&data->update_lock);
251 }
252 
253 static enum pca9532_state pca9532_getled(struct pca9532_led *led)
254 {
255 	struct i2c_client *client = led->client;
256 	struct pca9532_data *data = i2c_get_clientdata(client);
257 	u8 maxleds = data->chip_info->num_leds;
258 	char reg;
259 	enum pca9532_state ret;
260 
261 	mutex_lock(&data->update_lock);
262 	reg = i2c_smbus_read_byte_data(client, LED_REG(maxleds, led->id));
263 	ret = reg >> LED_NUM(led->id)/2;
264 	mutex_unlock(&data->update_lock);
265 	return ret;
266 }
267 
268 #ifdef CONFIG_LEDS_PCA9532_GPIO
269 static int pca9532_gpio_request_pin(struct gpio_chip *gc, unsigned offset)
270 {
271 	struct pca9532_data *data = gpiochip_get_data(gc);
272 	struct pca9532_led *led = &data->leds[offset];
273 
274 	if (led->type == PCA9532_TYPE_GPIO)
275 		return 0;
276 
277 	return -EBUSY;
278 }
279 
280 static void pca9532_gpio_set_value(struct gpio_chip *gc, unsigned offset, int val)
281 {
282 	struct pca9532_data *data = gpiochip_get_data(gc);
283 	struct pca9532_led *led = &data->leds[offset];
284 
285 	if (val)
286 		led->state = PCA9532_ON;
287 	else
288 		led->state = PCA9532_OFF;
289 
290 	pca9532_setled(led);
291 }
292 
293 static int pca9532_gpio_get_value(struct gpio_chip *gc, unsigned offset)
294 {
295 	struct pca9532_data *data = gpiochip_get_data(gc);
296 	unsigned char reg;
297 
298 	reg = i2c_smbus_read_byte_data(data->client, PCA9532_REG_INPUT(offset));
299 
300 	return !!(reg & (1 << (offset % 8)));
301 }
302 
303 static int pca9532_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
304 {
305 	/* To use as input ensure pin is not driven */
306 	pca9532_gpio_set_value(gc, offset, 0);
307 
308 	return 0;
309 }
310 
311 static int pca9532_gpio_direction_output(struct gpio_chip *gc, unsigned offset, int val)
312 {
313 	pca9532_gpio_set_value(gc, offset, val);
314 
315 	return 0;
316 }
317 #endif /* CONFIG_LEDS_PCA9532_GPIO */
318 
319 static int pca9532_destroy_devices(struct pca9532_data *data, int n_devs)
320 {
321 	int i = n_devs;
322 
323 	if (!data)
324 		return -EINVAL;
325 
326 	while (--i >= 0) {
327 		switch (data->leds[i].type) {
328 		case PCA9532_TYPE_NONE:
329 		case PCA9532_TYPE_GPIO:
330 			break;
331 		case PCA9532_TYPE_LED:
332 			led_classdev_unregister(&data->leds[i].ldev);
333 			break;
334 		case PCA9532_TYPE_N2100_BEEP:
335 			if (data->idev != NULL) {
336 				cancel_work_sync(&data->work);
337 				data->idev = NULL;
338 			}
339 			break;
340 		}
341 	}
342 
343 #ifdef CONFIG_LEDS_PCA9532_GPIO
344 	if (data->gpio.parent)
345 		gpiochip_remove(&data->gpio);
346 #endif
347 
348 	return 0;
349 }
350 
351 static int pca9532_configure(struct i2c_client *client,
352 	struct pca9532_data *data, struct pca9532_platform_data *pdata)
353 {
354 	int i, err = 0;
355 	int gpios = 0;
356 	u8 maxleds = data->chip_info->num_leds;
357 
358 	for (i = 0; i < 2; i++)	{
359 		data->pwm[i] = pdata->pwm[i];
360 		data->psc[i] = pdata->psc[i];
361 		i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(maxleds, i),
362 			data->pwm[i]);
363 		i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(maxleds, i),
364 			data->psc[i]);
365 	}
366 
367 	for (i = 0; i < data->chip_info->num_leds; i++) {
368 		struct pca9532_led *led = &data->leds[i];
369 		struct pca9532_led *pled = &pdata->leds[i];
370 		led->client = client;
371 		led->id = i;
372 		led->type = pled->type;
373 		switch (led->type) {
374 		case PCA9532_TYPE_NONE:
375 			break;
376 		case PCA9532_TYPE_GPIO:
377 			gpios++;
378 			break;
379 		case PCA9532_TYPE_LED:
380 			if (pled->state == PCA9532_KEEP)
381 				led->state = pca9532_getled(led);
382 			else
383 				led->state = pled->state;
384 			led->name = pled->name;
385 			led->ldev.name = led->name;
386 			led->ldev.default_trigger = pled->default_trigger;
387 			led->ldev.brightness = LED_OFF;
388 			led->ldev.brightness_set_blocking =
389 						pca9532_set_brightness;
390 			led->ldev.blink_set = pca9532_set_blink;
391 			err = led_classdev_register(&client->dev, &led->ldev);
392 			if (err < 0) {
393 				dev_err(&client->dev,
394 					"couldn't register LED %s\n",
395 					led->name);
396 				goto exit;
397 			}
398 			pca9532_setled(led);
399 			break;
400 		case PCA9532_TYPE_N2100_BEEP:
401 			BUG_ON(data->idev);
402 			led->state = PCA9532_PWM1;
403 			pca9532_setled(led);
404 			data->idev = devm_input_allocate_device(&client->dev);
405 			if (data->idev == NULL) {
406 				err = -ENOMEM;
407 				goto exit;
408 			}
409 			data->idev->name = pled->name;
410 			data->idev->phys = "i2c/pca9532";
411 			data->idev->id.bustype = BUS_HOST;
412 			data->idev->id.vendor = 0x001f;
413 			data->idev->id.product = 0x0001;
414 			data->idev->id.version = 0x0100;
415 			data->idev->evbit[0] = BIT_MASK(EV_SND);
416 			data->idev->sndbit[0] = BIT_MASK(SND_BELL) |
417 						BIT_MASK(SND_TONE);
418 			data->idev->event = pca9532_event;
419 			input_set_drvdata(data->idev, data);
420 			INIT_WORK(&data->work, pca9532_input_work);
421 			err = input_register_device(data->idev);
422 			if (err) {
423 				cancel_work_sync(&data->work);
424 				data->idev = NULL;
425 				goto exit;
426 			}
427 			break;
428 		}
429 	}
430 
431 #ifdef CONFIG_LEDS_PCA9532_GPIO
432 	if (gpios) {
433 		data->gpio.label = "gpio-pca9532";
434 		data->gpio.direction_input = pca9532_gpio_direction_input;
435 		data->gpio.direction_output = pca9532_gpio_direction_output;
436 		data->gpio.set = pca9532_gpio_set_value;
437 		data->gpio.get = pca9532_gpio_get_value;
438 		data->gpio.request = pca9532_gpio_request_pin;
439 		data->gpio.can_sleep = 1;
440 		data->gpio.base = pdata->gpio_base;
441 		data->gpio.ngpio = data->chip_info->num_leds;
442 		data->gpio.parent = &client->dev;
443 		data->gpio.owner = THIS_MODULE;
444 
445 		err = gpiochip_add_data(&data->gpio, data);
446 		if (err) {
447 			/* Use data->gpio.dev as a flag for freeing gpiochip */
448 			data->gpio.parent = NULL;
449 			dev_warn(&client->dev, "could not add gpiochip\n");
450 		} else {
451 			dev_info(&client->dev, "gpios %i...%i\n",
452 				data->gpio.base, data->gpio.base +
453 				data->gpio.ngpio - 1);
454 		}
455 	}
456 #endif
457 
458 	return 0;
459 
460 exit:
461 	pca9532_destroy_devices(data, i);
462 	return err;
463 }
464 
465 static struct pca9532_platform_data *
466 pca9532_of_populate_pdata(struct device *dev, struct device_node *np)
467 {
468 	struct pca9532_platform_data *pdata;
469 	struct device_node *child;
470 	const struct of_device_id *match;
471 	int devid, maxleds;
472 	int i = 0;
473 	const char *state;
474 
475 	match = of_match_device(of_pca9532_leds_match, dev);
476 	if (!match)
477 		return ERR_PTR(-ENODEV);
478 
479 	devid = (int)(uintptr_t)match->data;
480 	maxleds = pca9532_chip_info_tbl[devid].num_leds;
481 
482 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
483 	if (!pdata)
484 		return ERR_PTR(-ENOMEM);
485 
486 	for_each_child_of_node(np, child) {
487 		if (of_property_read_string(child, "label",
488 					    &pdata->leds[i].name))
489 			pdata->leds[i].name = child->name;
490 		of_property_read_u32(child, "type", &pdata->leds[i].type);
491 		of_property_read_string(child, "linux,default-trigger",
492 					&pdata->leds[i].default_trigger);
493 		if (!of_property_read_string(child, "default-state", &state)) {
494 			if (!strcmp(state, "on"))
495 				pdata->leds[i].state = PCA9532_ON;
496 			else if (!strcmp(state, "keep"))
497 				pdata->leds[i].state = PCA9532_KEEP;
498 		}
499 		if (++i >= maxleds) {
500 			of_node_put(child);
501 			break;
502 		}
503 	}
504 
505 	return pdata;
506 }
507 
508 static int pca9532_probe(struct i2c_client *client,
509 	const struct i2c_device_id *id)
510 {
511 	int devid;
512 	const struct of_device_id *of_id;
513 	struct pca9532_data *data = i2c_get_clientdata(client);
514 	struct pca9532_platform_data *pca9532_pdata =
515 			dev_get_platdata(&client->dev);
516 	struct device_node *np = client->dev.of_node;
517 
518 	if (!pca9532_pdata) {
519 		if (np) {
520 			pca9532_pdata =
521 				pca9532_of_populate_pdata(&client->dev, np);
522 			if (IS_ERR(pca9532_pdata))
523 				return PTR_ERR(pca9532_pdata);
524 		} else {
525 			dev_err(&client->dev, "no platform data\n");
526 			return -EINVAL;
527 		}
528 		of_id = of_match_device(of_pca9532_leds_match,
529 				&client->dev);
530 		if (unlikely(!of_id))
531 			return -EINVAL;
532 		devid = (int)(uintptr_t) of_id->data;
533 	} else {
534 		devid = id->driver_data;
535 	}
536 
537 	if (!i2c_check_functionality(client->adapter,
538 		I2C_FUNC_SMBUS_BYTE_DATA))
539 		return -EIO;
540 
541 	data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
542 	if (!data)
543 		return -ENOMEM;
544 
545 	data->chip_info = &pca9532_chip_info_tbl[devid];
546 
547 	dev_info(&client->dev, "setting platform data\n");
548 	i2c_set_clientdata(client, data);
549 	data->client = client;
550 	mutex_init(&data->update_lock);
551 
552 	return pca9532_configure(client, data, pca9532_pdata);
553 }
554 
555 static int pca9532_remove(struct i2c_client *client)
556 {
557 	struct pca9532_data *data = i2c_get_clientdata(client);
558 	int err;
559 
560 	err = pca9532_destroy_devices(data, data->chip_info->num_leds);
561 	if (err)
562 		return err;
563 
564 	return 0;
565 }
566 
567 module_i2c_driver(pca9532_driver);
568 
569 MODULE_AUTHOR("Riku Voipio");
570 MODULE_LICENSE("GPL");
571 MODULE_DESCRIPTION("PCA 9532 LED dimmer");
572