xref: /openbmc/linux/drivers/leds/leds-pca9532.c (revision a2818ee4)
1 /*
2  * pca9532.c - 16-bit Led dimmer
3  *
4  * Copyright (C) 2011 Jan Weitzel
5  * Copyright (C) 2008 Riku Voipio
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; version 2 of the License.
10  *
11  * Datasheet: http://www.nxp.com/documents/data_sheet/PCA9532.pdf
12  *
13  */
14 
15 #include <linux/module.h>
16 #include <linux/i2c.h>
17 #include <linux/slab.h>
18 #include <linux/leds.h>
19 #include <linux/input.h>
20 #include <linux/mutex.h>
21 #include <linux/workqueue.h>
22 #include <linux/leds-pca9532.h>
23 #include <linux/gpio.h>
24 #include <linux/of.h>
25 #include <linux/of_device.h>
26 
27 /* m =  num_leds*/
28 #define PCA9532_REG_INPUT(i)	((i) >> 3)
29 #define PCA9532_REG_OFFSET(m)	((m) >> 4)
30 #define PCA9532_REG_PSC(m, i)	(PCA9532_REG_OFFSET(m) + 0x1 + (i) * 2)
31 #define PCA9532_REG_PWM(m, i)	(PCA9532_REG_OFFSET(m) + 0x2 + (i) * 2)
32 #define LED_REG(m, led)		(PCA9532_REG_OFFSET(m) + 0x5 + (led >> 2))
33 #define LED_NUM(led)		(led & 0x3)
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 	u8 pwm[2];
52 	u8 psc[2];
53 };
54 
55 static int pca9532_probe(struct i2c_client *client,
56 	const struct i2c_device_id *id);
57 static int pca9532_remove(struct i2c_client *client);
58 
59 enum {
60 	pca9530,
61 	pca9531,
62 	pca9532,
63 	pca9533,
64 };
65 
66 static const struct i2c_device_id pca9532_id[] = {
67 	{ "pca9530", pca9530 },
68 	{ "pca9531", pca9531 },
69 	{ "pca9532", pca9532 },
70 	{ "pca9533", pca9533 },
71 	{ }
72 };
73 
74 MODULE_DEVICE_TABLE(i2c, pca9532_id);
75 
76 static const struct pca9532_chip_info pca9532_chip_info_tbl[] = {
77 	[pca9530] = {
78 		.num_leds = 2,
79 	},
80 	[pca9531] = {
81 		.num_leds = 8,
82 	},
83 	[pca9532] = {
84 		.num_leds = 16,
85 	},
86 	[pca9533] = {
87 		.num_leds = 4,
88 	},
89 };
90 
91 #ifdef CONFIG_OF
92 static const struct of_device_id of_pca9532_leds_match[] = {
93 	{ .compatible = "nxp,pca9530", .data = (void *)pca9530 },
94 	{ .compatible = "nxp,pca9531", .data = (void *)pca9531 },
95 	{ .compatible = "nxp,pca9532", .data = (void *)pca9532 },
96 	{ .compatible = "nxp,pca9533", .data = (void *)pca9533 },
97 	{},
98 };
99 
100 MODULE_DEVICE_TABLE(of, of_pca9532_leds_match);
101 #endif
102 
103 static struct i2c_driver pca9532_driver = {
104 	.driver = {
105 		.name = "leds-pca953x",
106 		.of_match_table = of_match_ptr(of_pca9532_leds_match),
107 	},
108 	.probe = pca9532_probe,
109 	.remove = pca9532_remove,
110 	.id_table = pca9532_id,
111 };
112 
113 /* We have two pwm/blinkers, but 16 possible leds to drive. Additionally,
114  * the clever Thecus people are using one pwm to drive the beeper. So,
115  * as a compromise we average one pwm to the values requested by all
116  * leds that are not ON/OFF.
117  * */
118 static int pca9532_calcpwm(struct i2c_client *client, int pwm, int blink,
119 	enum led_brightness value)
120 {
121 	int a = 0, b = 0, i = 0;
122 	struct pca9532_data *data = i2c_get_clientdata(client);
123 	for (i = 0; i < data->chip_info->num_leds; i++) {
124 		if (data->leds[i].type == PCA9532_TYPE_LED &&
125 			data->leds[i].state == PCA9532_PWM0+pwm) {
126 				a++;
127 				b += data->leds[i].ldev.brightness;
128 		}
129 	}
130 	if (a == 0) {
131 		dev_err(&client->dev,
132 		"fear of division by zero %d/%d, wanted %d\n",
133 			b, a, value);
134 		return -EINVAL;
135 	}
136 	b = b/a;
137 	if (b > 0xFF)
138 		return -EINVAL;
139 	data->pwm[pwm] = b;
140 	data->psc[pwm] = blink;
141 	return 0;
142 }
143 
144 static int pca9532_setpwm(struct i2c_client *client, int pwm)
145 {
146 	struct pca9532_data *data = i2c_get_clientdata(client);
147 	u8 maxleds = data->chip_info->num_leds;
148 
149 	mutex_lock(&data->update_lock);
150 	i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(maxleds, pwm),
151 		data->pwm[pwm]);
152 	i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(maxleds, pwm),
153 		data->psc[pwm]);
154 	mutex_unlock(&data->update_lock);
155 	return 0;
156 }
157 
158 /* Set LED routing */
159 static void pca9532_setled(struct pca9532_led *led)
160 {
161 	struct i2c_client *client = led->client;
162 	struct pca9532_data *data = i2c_get_clientdata(client);
163 	u8 maxleds = data->chip_info->num_leds;
164 	char reg;
165 
166 	mutex_lock(&data->update_lock);
167 	reg = i2c_smbus_read_byte_data(client, LED_REG(maxleds, led->id));
168 	/* zero led bits */
169 	reg = reg & ~(0x3<<LED_NUM(led->id)*2);
170 	/* set the new value */
171 	reg = reg | (led->state << LED_NUM(led->id)*2);
172 	i2c_smbus_write_byte_data(client, LED_REG(maxleds, led->id), reg);
173 	mutex_unlock(&data->update_lock);
174 }
175 
176 static int pca9532_set_brightness(struct led_classdev *led_cdev,
177 	enum led_brightness value)
178 {
179 	int err = 0;
180 	struct pca9532_led *led = ldev_to_led(led_cdev);
181 
182 	if (value == LED_OFF)
183 		led->state = PCA9532_OFF;
184 	else if (value == LED_FULL)
185 		led->state = PCA9532_ON;
186 	else {
187 		led->state = PCA9532_PWM0; /* Thecus: hardcode one pwm */
188 		err = pca9532_calcpwm(led->client, 0, 0, value);
189 		if (err)
190 			return err;
191 	}
192 	if (led->state == PCA9532_PWM0)
193 		pca9532_setpwm(led->client, 0);
194 	pca9532_setled(led);
195 	return err;
196 }
197 
198 static int pca9532_set_blink(struct led_classdev *led_cdev,
199 	unsigned long *delay_on, unsigned long *delay_off)
200 {
201 	struct pca9532_led *led = ldev_to_led(led_cdev);
202 	struct i2c_client *client = led->client;
203 	int psc;
204 	int err = 0;
205 
206 	if (*delay_on == 0 && *delay_off == 0) {
207 		/* led subsystem ask us for a blink rate */
208 		*delay_on = 1000;
209 		*delay_off = 1000;
210 	}
211 	if (*delay_on != *delay_off || *delay_on > 1690 || *delay_on < 6)
212 		return -EINVAL;
213 
214 	/* Thecus specific: only use PSC/PWM 0 */
215 	psc = (*delay_on * 152-1)/1000;
216 	err = pca9532_calcpwm(client, 0, psc, led_cdev->brightness);
217 	if (err)
218 		return err;
219 	if (led->state == PCA9532_PWM0)
220 		pca9532_setpwm(led->client, 0);
221 	pca9532_setled(led);
222 
223 	return 0;
224 }
225 
226 static int pca9532_event(struct input_dev *dev, unsigned int type,
227 	unsigned int code, int value)
228 {
229 	struct pca9532_data *data = input_get_drvdata(dev);
230 
231 	if (!(type == EV_SND && (code == SND_BELL || code == SND_TONE)))
232 		return -1;
233 
234 	/* XXX: allow different kind of beeps with psc/pwm modifications */
235 	if (value > 1 && value < 32767)
236 		data->pwm[1] = 127;
237 	else
238 		data->pwm[1] = 0;
239 
240 	schedule_work(&data->work);
241 
242 	return 0;
243 }
244 
245 static void pca9532_input_work(struct work_struct *work)
246 {
247 	struct pca9532_data *data =
248 		container_of(work, struct pca9532_data, work);
249 	u8 maxleds = data->chip_info->num_leds;
250 
251 	mutex_lock(&data->update_lock);
252 	i2c_smbus_write_byte_data(data->client, PCA9532_REG_PWM(maxleds, 1),
253 		data->pwm[1]);
254 	mutex_unlock(&data->update_lock);
255 }
256 
257 static enum pca9532_state pca9532_getled(struct pca9532_led *led)
258 {
259 	struct i2c_client *client = led->client;
260 	struct pca9532_data *data = i2c_get_clientdata(client);
261 	u8 maxleds = data->chip_info->num_leds;
262 	char reg;
263 	enum pca9532_state ret;
264 
265 	mutex_lock(&data->update_lock);
266 	reg = i2c_smbus_read_byte_data(client, LED_REG(maxleds, led->id));
267 	ret = reg >> LED_NUM(led->id)/2;
268 	mutex_unlock(&data->update_lock);
269 	return ret;
270 }
271 
272 #ifdef CONFIG_LEDS_PCA9532_GPIO
273 static int pca9532_gpio_request_pin(struct gpio_chip *gc, unsigned offset)
274 {
275 	struct pca9532_data *data = gpiochip_get_data(gc);
276 	struct pca9532_led *led = &data->leds[offset];
277 
278 	if (led->type == PCA9532_TYPE_GPIO)
279 		return 0;
280 
281 	return -EBUSY;
282 }
283 
284 static void pca9532_gpio_set_value(struct gpio_chip *gc, unsigned offset, int val)
285 {
286 	struct pca9532_data *data = gpiochip_get_data(gc);
287 	struct pca9532_led *led = &data->leds[offset];
288 
289 	if (val)
290 		led->state = PCA9532_ON;
291 	else
292 		led->state = PCA9532_OFF;
293 
294 	pca9532_setled(led);
295 }
296 
297 static int pca9532_gpio_get_value(struct gpio_chip *gc, unsigned offset)
298 {
299 	struct pca9532_data *data = gpiochip_get_data(gc);
300 	unsigned char reg;
301 
302 	reg = i2c_smbus_read_byte_data(data->client, PCA9532_REG_INPUT(offset));
303 
304 	return !!(reg & (1 << (offset % 8)));
305 }
306 
307 static int pca9532_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
308 {
309 	/* To use as input ensure pin is not driven */
310 	pca9532_gpio_set_value(gc, offset, 0);
311 
312 	return 0;
313 }
314 
315 static int pca9532_gpio_direction_output(struct gpio_chip *gc, unsigned offset, int val)
316 {
317 	pca9532_gpio_set_value(gc, offset, val);
318 
319 	return 0;
320 }
321 #endif /* CONFIG_LEDS_PCA9532_GPIO */
322 
323 static int pca9532_destroy_devices(struct pca9532_data *data, int n_devs)
324 {
325 	int i = n_devs;
326 
327 	if (!data)
328 		return -EINVAL;
329 
330 	while (--i >= 0) {
331 		switch (data->leds[i].type) {
332 		case PCA9532_TYPE_NONE:
333 		case PCA9532_TYPE_GPIO:
334 			break;
335 		case PCA9532_TYPE_LED:
336 			led_classdev_unregister(&data->leds[i].ldev);
337 			break;
338 		case PCA9532_TYPE_N2100_BEEP:
339 			if (data->idev != NULL) {
340 				cancel_work_sync(&data->work);
341 				data->idev = NULL;
342 			}
343 			break;
344 		}
345 	}
346 
347 #ifdef CONFIG_LEDS_PCA9532_GPIO
348 	if (data->gpio.parent)
349 		gpiochip_remove(&data->gpio);
350 #endif
351 
352 	return 0;
353 }
354 
355 static int pca9532_configure(struct i2c_client *client,
356 	struct pca9532_data *data, struct pca9532_platform_data *pdata)
357 {
358 	int i, err = 0;
359 	int gpios = 0;
360 	u8 maxleds = data->chip_info->num_leds;
361 
362 	for (i = 0; i < 2; i++)	{
363 		data->pwm[i] = pdata->pwm[i];
364 		data->psc[i] = pdata->psc[i];
365 		i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(maxleds, i),
366 			data->pwm[i]);
367 		i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(maxleds, i),
368 			data->psc[i]);
369 	}
370 
371 	for (i = 0; i < data->chip_info->num_leds; i++) {
372 		struct pca9532_led *led = &data->leds[i];
373 		struct pca9532_led *pled = &pdata->leds[i];
374 		led->client = client;
375 		led->id = i;
376 		led->type = pled->type;
377 		switch (led->type) {
378 		case PCA9532_TYPE_NONE:
379 			break;
380 		case PCA9532_TYPE_GPIO:
381 			gpios++;
382 			break;
383 		case PCA9532_TYPE_LED:
384 			if (pled->state == PCA9532_KEEP)
385 				led->state = pca9532_getled(led);
386 			else
387 				led->state = pled->state;
388 			led->name = pled->name;
389 			led->ldev.name = led->name;
390 			led->ldev.default_trigger = pled->default_trigger;
391 			led->ldev.brightness = LED_OFF;
392 			led->ldev.brightness_set_blocking =
393 						pca9532_set_brightness;
394 			led->ldev.blink_set = pca9532_set_blink;
395 			err = led_classdev_register(&client->dev, &led->ldev);
396 			if (err < 0) {
397 				dev_err(&client->dev,
398 					"couldn't register LED %s\n",
399 					led->name);
400 				goto exit;
401 			}
402 			pca9532_setled(led);
403 			break;
404 		case PCA9532_TYPE_N2100_BEEP:
405 			BUG_ON(data->idev);
406 			led->state = PCA9532_PWM1;
407 			pca9532_setled(led);
408 			data->idev = devm_input_allocate_device(&client->dev);
409 			if (data->idev == NULL) {
410 				err = -ENOMEM;
411 				goto exit;
412 			}
413 			data->idev->name = pled->name;
414 			data->idev->phys = "i2c/pca9532";
415 			data->idev->id.bustype = BUS_HOST;
416 			data->idev->id.vendor = 0x001f;
417 			data->idev->id.product = 0x0001;
418 			data->idev->id.version = 0x0100;
419 			data->idev->evbit[0] = BIT_MASK(EV_SND);
420 			data->idev->sndbit[0] = BIT_MASK(SND_BELL) |
421 						BIT_MASK(SND_TONE);
422 			data->idev->event = pca9532_event;
423 			input_set_drvdata(data->idev, data);
424 			INIT_WORK(&data->work, pca9532_input_work);
425 			err = input_register_device(data->idev);
426 			if (err) {
427 				cancel_work_sync(&data->work);
428 				data->idev = NULL;
429 				goto exit;
430 			}
431 			break;
432 		}
433 	}
434 
435 #ifdef CONFIG_LEDS_PCA9532_GPIO
436 	if (gpios) {
437 		data->gpio.label = "gpio-pca9532";
438 		data->gpio.direction_input = pca9532_gpio_direction_input;
439 		data->gpio.direction_output = pca9532_gpio_direction_output;
440 		data->gpio.set = pca9532_gpio_set_value;
441 		data->gpio.get = pca9532_gpio_get_value;
442 		data->gpio.request = pca9532_gpio_request_pin;
443 		data->gpio.can_sleep = 1;
444 		data->gpio.base = pdata->gpio_base;
445 		data->gpio.ngpio = data->chip_info->num_leds;
446 		data->gpio.parent = &client->dev;
447 		data->gpio.owner = THIS_MODULE;
448 
449 		err = gpiochip_add_data(&data->gpio, data);
450 		if (err) {
451 			/* Use data->gpio.dev as a flag for freeing gpiochip */
452 			data->gpio.parent = NULL;
453 			dev_warn(&client->dev, "could not add gpiochip\n");
454 		} else {
455 			dev_info(&client->dev, "gpios %i...%i\n",
456 				data->gpio.base, data->gpio.base +
457 				data->gpio.ngpio - 1);
458 		}
459 	}
460 #endif
461 
462 	return 0;
463 
464 exit:
465 	pca9532_destroy_devices(data, i);
466 	return err;
467 }
468 
469 static struct pca9532_platform_data *
470 pca9532_of_populate_pdata(struct device *dev, struct device_node *np)
471 {
472 	struct pca9532_platform_data *pdata;
473 	struct device_node *child;
474 	const struct of_device_id *match;
475 	int devid, maxleds;
476 	int i = 0;
477 	const char *state;
478 
479 	match = of_match_device(of_pca9532_leds_match, dev);
480 	if (!match)
481 		return ERR_PTR(-ENODEV);
482 
483 	devid = (int)(uintptr_t)match->data;
484 	maxleds = pca9532_chip_info_tbl[devid].num_leds;
485 
486 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
487 	if (!pdata)
488 		return ERR_PTR(-ENOMEM);
489 
490 	for_each_child_of_node(np, child) {
491 		if (of_property_read_string(child, "label",
492 					    &pdata->leds[i].name))
493 			pdata->leds[i].name = child->name;
494 		of_property_read_u32(child, "type", &pdata->leds[i].type);
495 		of_property_read_string(child, "linux,default-trigger",
496 					&pdata->leds[i].default_trigger);
497 		if (!of_property_read_string(child, "default-state", &state)) {
498 			if (!strcmp(state, "on"))
499 				pdata->leds[i].state = PCA9532_ON;
500 			else if (!strcmp(state, "keep"))
501 				pdata->leds[i].state = PCA9532_KEEP;
502 		}
503 		if (++i >= maxleds) {
504 			of_node_put(child);
505 			break;
506 		}
507 	}
508 
509 	return pdata;
510 }
511 
512 static int pca9532_probe(struct i2c_client *client,
513 	const struct i2c_device_id *id)
514 {
515 	int devid;
516 	struct pca9532_data *data = i2c_get_clientdata(client);
517 	struct pca9532_platform_data *pca9532_pdata =
518 			dev_get_platdata(&client->dev);
519 	struct device_node *np = client->dev.of_node;
520 
521 	if (!pca9532_pdata) {
522 		if (np) {
523 			pca9532_pdata =
524 				pca9532_of_populate_pdata(&client->dev, np);
525 			if (IS_ERR(pca9532_pdata))
526 				return PTR_ERR(pca9532_pdata);
527 		} else {
528 			dev_err(&client->dev, "no platform data\n");
529 			return -EINVAL;
530 		}
531 		devid = (int)(uintptr_t)of_match_device(
532 			of_pca9532_leds_match, &client->dev)->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