xref: /linux/drivers/leds/leds-pca9532.c (revision f3a8b6645dc2e60d11f20c1c23afd964ff4e55ae)
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 #ifdef CONFIG_LEDS_PCA9532_GPIO
258 static int pca9532_gpio_request_pin(struct gpio_chip *gc, unsigned offset)
259 {
260 	struct pca9532_data *data = gpiochip_get_data(gc);
261 	struct pca9532_led *led = &data->leds[offset];
262 
263 	if (led->type == PCA9532_TYPE_GPIO)
264 		return 0;
265 
266 	return -EBUSY;
267 }
268 
269 static void pca9532_gpio_set_value(struct gpio_chip *gc, unsigned offset, int val)
270 {
271 	struct pca9532_data *data = gpiochip_get_data(gc);
272 	struct pca9532_led *led = &data->leds[offset];
273 
274 	if (val)
275 		led->state = PCA9532_ON;
276 	else
277 		led->state = PCA9532_OFF;
278 
279 	pca9532_setled(led);
280 }
281 
282 static int pca9532_gpio_get_value(struct gpio_chip *gc, unsigned offset)
283 {
284 	struct pca9532_data *data = gpiochip_get_data(gc);
285 	unsigned char reg;
286 
287 	reg = i2c_smbus_read_byte_data(data->client, PCA9532_REG_INPUT(offset));
288 
289 	return !!(reg & (1 << (offset % 8)));
290 }
291 
292 static int pca9532_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
293 {
294 	/* To use as input ensure pin is not driven */
295 	pca9532_gpio_set_value(gc, offset, 0);
296 
297 	return 0;
298 }
299 
300 static int pca9532_gpio_direction_output(struct gpio_chip *gc, unsigned offset, int val)
301 {
302 	pca9532_gpio_set_value(gc, offset, val);
303 
304 	return 0;
305 }
306 #endif /* CONFIG_LEDS_PCA9532_GPIO */
307 
308 static int pca9532_destroy_devices(struct pca9532_data *data, int n_devs)
309 {
310 	int i = n_devs;
311 
312 	if (!data)
313 		return -EINVAL;
314 
315 	while (--i >= 0) {
316 		switch (data->leds[i].type) {
317 		case PCA9532_TYPE_NONE:
318 		case PCA9532_TYPE_GPIO:
319 			break;
320 		case PCA9532_TYPE_LED:
321 			led_classdev_unregister(&data->leds[i].ldev);
322 			break;
323 		case PCA9532_TYPE_N2100_BEEP:
324 			if (data->idev != NULL) {
325 				cancel_work_sync(&data->work);
326 				data->idev = NULL;
327 			}
328 			break;
329 		}
330 	}
331 
332 #ifdef CONFIG_LEDS_PCA9532_GPIO
333 	if (data->gpio.parent)
334 		gpiochip_remove(&data->gpio);
335 #endif
336 
337 	return 0;
338 }
339 
340 static int pca9532_configure(struct i2c_client *client,
341 	struct pca9532_data *data, struct pca9532_platform_data *pdata)
342 {
343 	int i, err = 0;
344 	int gpios = 0;
345 	u8 maxleds = data->chip_info->num_leds;
346 
347 	for (i = 0; i < 2; i++)	{
348 		data->pwm[i] = pdata->pwm[i];
349 		data->psc[i] = pdata->psc[i];
350 		i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(maxleds, i),
351 			data->pwm[i]);
352 		i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(maxleds, i),
353 			data->psc[i]);
354 	}
355 
356 	for (i = 0; i < data->chip_info->num_leds; i++) {
357 		struct pca9532_led *led = &data->leds[i];
358 		struct pca9532_led *pled = &pdata->leds[i];
359 		led->client = client;
360 		led->id = i;
361 		led->type = pled->type;
362 		switch (led->type) {
363 		case PCA9532_TYPE_NONE:
364 			break;
365 		case PCA9532_TYPE_GPIO:
366 			gpios++;
367 			break;
368 		case PCA9532_TYPE_LED:
369 			led->state = pled->state;
370 			led->name = pled->name;
371 			led->ldev.name = led->name;
372 			led->ldev.default_trigger = led->default_trigger;
373 			led->ldev.brightness = LED_OFF;
374 			led->ldev.brightness_set_blocking =
375 						pca9532_set_brightness;
376 			led->ldev.blink_set = pca9532_set_blink;
377 			err = led_classdev_register(&client->dev, &led->ldev);
378 			if (err < 0) {
379 				dev_err(&client->dev,
380 					"couldn't register LED %s\n",
381 					led->name);
382 				goto exit;
383 			}
384 			pca9532_setled(led);
385 			break;
386 		case PCA9532_TYPE_N2100_BEEP:
387 			BUG_ON(data->idev);
388 			led->state = PCA9532_PWM1;
389 			pca9532_setled(led);
390 			data->idev = devm_input_allocate_device(&client->dev);
391 			if (data->idev == NULL) {
392 				err = -ENOMEM;
393 				goto exit;
394 			}
395 			data->idev->name = pled->name;
396 			data->idev->phys = "i2c/pca9532";
397 			data->idev->id.bustype = BUS_HOST;
398 			data->idev->id.vendor = 0x001f;
399 			data->idev->id.product = 0x0001;
400 			data->idev->id.version = 0x0100;
401 			data->idev->evbit[0] = BIT_MASK(EV_SND);
402 			data->idev->sndbit[0] = BIT_MASK(SND_BELL) |
403 						BIT_MASK(SND_TONE);
404 			data->idev->event = pca9532_event;
405 			input_set_drvdata(data->idev, data);
406 			INIT_WORK(&data->work, pca9532_input_work);
407 			err = input_register_device(data->idev);
408 			if (err) {
409 				cancel_work_sync(&data->work);
410 				data->idev = NULL;
411 				goto exit;
412 			}
413 			break;
414 		}
415 	}
416 
417 #ifdef CONFIG_LEDS_PCA9532_GPIO
418 	if (gpios) {
419 		data->gpio.label = "gpio-pca9532";
420 		data->gpio.direction_input = pca9532_gpio_direction_input;
421 		data->gpio.direction_output = pca9532_gpio_direction_output;
422 		data->gpio.set = pca9532_gpio_set_value;
423 		data->gpio.get = pca9532_gpio_get_value;
424 		data->gpio.request = pca9532_gpio_request_pin;
425 		data->gpio.can_sleep = 1;
426 		data->gpio.base = pdata->gpio_base;
427 		data->gpio.ngpio = data->chip_info->num_leds;
428 		data->gpio.parent = &client->dev;
429 		data->gpio.owner = THIS_MODULE;
430 
431 		err = gpiochip_add_data(&data->gpio, data);
432 		if (err) {
433 			/* Use data->gpio.dev as a flag for freeing gpiochip */
434 			data->gpio.parent = NULL;
435 			dev_warn(&client->dev, "could not add gpiochip\n");
436 		} else {
437 			dev_info(&client->dev, "gpios %i...%i\n",
438 				data->gpio.base, data->gpio.base +
439 				data->gpio.ngpio - 1);
440 		}
441 	}
442 #endif
443 
444 	return 0;
445 
446 exit:
447 	pca9532_destroy_devices(data, i);
448 	return err;
449 }
450 
451 static struct pca9532_platform_data *
452 pca9532_of_populate_pdata(struct device *dev, struct device_node *np)
453 {
454 	struct pca9532_platform_data *pdata;
455 	struct device_node *child;
456 	const struct of_device_id *match;
457 	int devid, maxleds;
458 	int i = 0;
459 
460 	match = of_match_device(of_pca9532_leds_match, dev);
461 	if (!match)
462 		return ERR_PTR(-ENODEV);
463 
464 	devid = (int)(uintptr_t)match->data;
465 	maxleds = pca9532_chip_info_tbl[devid].num_leds;
466 
467 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
468 	if (!pdata)
469 		return ERR_PTR(-ENOMEM);
470 
471 	for_each_child_of_node(np, child) {
472 		if (of_property_read_string(child, "label",
473 					    &pdata->leds[i].name))
474 			pdata->leds[i].name = child->name;
475 		of_property_read_u32(child, "type", &pdata->leds[i].type);
476 		of_property_read_string(child, "linux,default-trigger",
477 					&pdata->leds[i].default_trigger);
478 		if (++i >= maxleds) {
479 			of_node_put(child);
480 			break;
481 		}
482 	}
483 
484 	return pdata;
485 }
486 
487 static int pca9532_probe(struct i2c_client *client,
488 	const struct i2c_device_id *id)
489 {
490 	int devid;
491 	struct pca9532_data *data = i2c_get_clientdata(client);
492 	struct pca9532_platform_data *pca9532_pdata =
493 			dev_get_platdata(&client->dev);
494 	struct device_node *np = client->dev.of_node;
495 
496 	if (!pca9532_pdata) {
497 		if (np) {
498 			pca9532_pdata =
499 				pca9532_of_populate_pdata(&client->dev, np);
500 			if (IS_ERR(pca9532_pdata))
501 				return PTR_ERR(pca9532_pdata);
502 		} else {
503 			dev_err(&client->dev, "no platform data\n");
504 			return -EINVAL;
505 		}
506 		devid = (int)(uintptr_t)of_match_device(
507 			of_pca9532_leds_match, &client->dev)->data;
508 	} else {
509 		devid = id->driver_data;
510 	}
511 
512 	if (!i2c_check_functionality(client->adapter,
513 		I2C_FUNC_SMBUS_BYTE_DATA))
514 		return -EIO;
515 
516 	data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
517 	if (!data)
518 		return -ENOMEM;
519 
520 	data->chip_info = &pca9532_chip_info_tbl[devid];
521 
522 	dev_info(&client->dev, "setting platform data\n");
523 	i2c_set_clientdata(client, data);
524 	data->client = client;
525 	mutex_init(&data->update_lock);
526 
527 	return pca9532_configure(client, data, pca9532_pdata);
528 }
529 
530 static int pca9532_remove(struct i2c_client *client)
531 {
532 	struct pca9532_data *data = i2c_get_clientdata(client);
533 	int err;
534 
535 	err = pca9532_destroy_devices(data, data->chip_info->num_leds);
536 	if (err)
537 		return err;
538 
539 	return 0;
540 }
541 
542 module_i2c_driver(pca9532_driver);
543 
544 MODULE_AUTHOR("Riku Voipio");
545 MODULE_LICENSE("GPL");
546 MODULE_DESCRIPTION("PCA 9532 LED dimmer");
547