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
37struct pca9532_chip_info {
38 u8 num_leds;
39};
40
41struct 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
59static int pca9532_probe(struct i2c_client *client);
60static void pca9532_remove(struct i2c_client *client);
61
62enum {
63 pca9530,
64 pca9531,
65 pca9532,
66 pca9533,
67};
68
69static const struct i2c_device_id pca9532_id[] = {
70 { "pca9530", pca9530 },
71 { "pca9531", pca9531 },
72 { "pca9532", pca9532 },
73 { "pca9533", pca9533 },
74 { }
75};
76
77MODULE_DEVICE_TABLE(i2c, pca9532_id);
78
79static 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
95static 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
103MODULE_DEVICE_TABLE(of, of_pca9532_leds_match);
104#endif
105
106static 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 * */
121static 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
147static 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 value: data->pwm[pwm]);
155 i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(maxleds, pwm),
156 value: data->psc[pwm]);
157 mutex_unlock(lock: &data->update_lock);
158 return 0;
159}
160
161/* Set LED routing */
162static 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), value: reg);
176 mutex_unlock(lock: &data->update_lock);
177}
178
179static 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(client: led->client, PCA9532_PWM_ID_0, blink: 0, value);
192 if (err)
193 return err;
194 }
195 if (led->state == PCA9532_PWM0)
196 pca9532_setpwm(client: led->client, PCA9532_PWM_ID_0);
197 pca9532_setled(led);
198 return err;
199}
200
201static 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(client: 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(client: data->client, PCA9532_PWM_ID_1);
235}
236
237static 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_on, delay_off: *delay_off);
255 if (err)
256 return err;
257
258 pca9532_setled(led);
259
260 return 0;
261}
262
263static 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(work: &data->work);
278
279 return 0;
280}
281
282static 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(client: data->client, PCA9532_REG_PWM(maxleds, 1),
290 value: data->pwm[PCA9532_PWM_ID_1]);
291 mutex_unlock(lock: &data->update_lock);
292}
293
294static 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(lock: &data->update_lock);
306 return ret;
307}
308
309#ifdef CONFIG_LEDS_PCA9532_GPIO
310static 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
321static int pca9532_gpio_set_value(struct gpio_chip *gc, unsigned int offset,
322 int val)
323{
324 struct pca9532_data *data = gpiochip_get_data(gc);
325 struct pca9532_led *led = &data->leds[offset];
326
327 if (val)
328 led->state = PCA9532_ON;
329 else
330 led->state = PCA9532_OFF;
331
332 pca9532_setled(led);
333
334 return 0;
335}
336
337static int pca9532_gpio_get_value(struct gpio_chip *gc, unsigned offset)
338{
339 struct pca9532_data *data = gpiochip_get_data(gc);
340 unsigned char reg;
341
342 reg = i2c_smbus_read_byte_data(client: data->client, PCA9532_REG_INPUT(offset));
343
344 return !!(reg & (1 << (offset % 8)));
345}
346
347static int pca9532_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
348{
349 /* To use as input ensure pin is not driven */
350 pca9532_gpio_set_value(gc, offset, val: 0);
351
352 return 0;
353}
354
355static int pca9532_gpio_direction_output(struct gpio_chip *gc, unsigned offset, int val)
356{
357 return pca9532_gpio_set_value(gc, offset, val);
358}
359#endif /* CONFIG_LEDS_PCA9532_GPIO */
360
361static void pca9532_destroy_devices(struct pca9532_data *data, int n_devs)
362{
363 int i = n_devs;
364
365 while (--i >= 0) {
366 switch (data->leds[i].type) {
367 case PCA9532_TYPE_NONE:
368 case PCA9532_TYPE_GPIO:
369 break;
370 case PCA9532_TYPE_LED:
371 led_classdev_unregister(led_cdev: &data->leds[i].ldev);
372 break;
373 case PCA9532_TYPE_N2100_BEEP:
374 if (data->idev != NULL) {
375 cancel_work_sync(work: &data->work);
376 data->idev = NULL;
377 }
378 break;
379 }
380 }
381
382#ifdef CONFIG_LEDS_PCA9532_GPIO
383 if (data->gpio.parent)
384 gpiochip_remove(gc: &data->gpio);
385#endif
386}
387
388static int pca9532_configure(struct i2c_client *client,
389 struct pca9532_data *data, struct pca9532_platform_data *pdata)
390{
391 int i, err = 0;
392 int gpios = 0;
393 u8 maxleds = data->chip_info->num_leds;
394
395 for (i = 0; i < 2; i++) {
396 data->pwm[i] = pdata->pwm[i];
397 data->psc[i] = pdata->psc[i];
398 i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(maxleds, i),
399 value: data->pwm[i]);
400 i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(maxleds, i),
401 value: data->psc[i]);
402 }
403
404 data->hw_blink = true;
405 for (i = 0; i < data->chip_info->num_leds; i++) {
406 struct pca9532_led *led = &data->leds[i];
407 struct pca9532_led *pled = &pdata->leds[i];
408 led->client = client;
409 led->id = i;
410 led->type = pled->type;
411 switch (led->type) {
412 case PCA9532_TYPE_NONE:
413 break;
414 case PCA9532_TYPE_GPIO:
415 gpios++;
416 break;
417 case PCA9532_TYPE_LED:
418 if (pled->state == PCA9532_KEEP)
419 led->state = pca9532_getled(led);
420 else
421 led->state = pled->state;
422 led->name = pled->name;
423 led->ldev.name = led->name;
424 led->ldev.default_trigger = pled->default_trigger;
425 led->ldev.brightness = LED_OFF;
426 led->ldev.brightness_set_blocking =
427 pca9532_set_brightness;
428 led->ldev.blink_set = pca9532_set_blink;
429 err = led_classdev_register(parent: &client->dev, led_cdev: &led->ldev);
430 if (err < 0) {
431 dev_err(&client->dev,
432 "couldn't register LED %s\n",
433 led->name);
434 goto exit;
435 }
436 pca9532_setled(led);
437 break;
438 case PCA9532_TYPE_N2100_BEEP:
439 /* PWM1 is reserved for beeper so blink will not use hardware */
440 data->hw_blink = false;
441 BUG_ON(data->idev);
442 led->state = PCA9532_PWM1;
443 pca9532_setled(led);
444 data->idev = devm_input_allocate_device(&client->dev);
445 if (data->idev == NULL) {
446 err = -ENOMEM;
447 goto exit;
448 }
449 data->idev->name = pled->name;
450 data->idev->phys = "i2c/pca9532";
451 data->idev->id.bustype = BUS_HOST;
452 data->idev->id.vendor = 0x001f;
453 data->idev->id.product = 0x0001;
454 data->idev->id.version = 0x0100;
455 data->idev->evbit[0] = BIT_MASK(EV_SND);
456 data->idev->sndbit[0] = BIT_MASK(SND_BELL) |
457 BIT_MASK(SND_TONE);
458 data->idev->event = pca9532_event;
459 input_set_drvdata(dev: data->idev, data);
460 INIT_WORK(&data->work, pca9532_input_work);
461 err = input_register_device(data->idev);
462 if (err) {
463 cancel_work_sync(work: &data->work);
464 data->idev = NULL;
465 goto exit;
466 }
467 break;
468 }
469 }
470
471#ifdef CONFIG_LEDS_PCA9532_GPIO
472 if (gpios) {
473 data->gpio.label = "gpio-pca9532";
474 data->gpio.direction_input = pca9532_gpio_direction_input;
475 data->gpio.direction_output = pca9532_gpio_direction_output;
476 data->gpio.set_rv = pca9532_gpio_set_value;
477 data->gpio.get = pca9532_gpio_get_value;
478 data->gpio.request = pca9532_gpio_request_pin;
479 data->gpio.can_sleep = 1;
480 data->gpio.base = pdata->gpio_base;
481 data->gpio.ngpio = data->chip_info->num_leds;
482 data->gpio.parent = &client->dev;
483 data->gpio.owner = THIS_MODULE;
484
485 err = gpiochip_add_data(&data->gpio, data);
486 if (err) {
487 /* Use data->gpio.dev as a flag for freeing gpiochip */
488 data->gpio.parent = NULL;
489 dev_warn(&client->dev, "could not add gpiochip\n");
490 } else {
491 dev_info(&client->dev, "gpios %i...%i\n",
492 data->gpio.base, data->gpio.base +
493 data->gpio.ngpio - 1);
494 }
495 }
496#endif
497
498 return 0;
499
500exit:
501 pca9532_destroy_devices(data, n_devs: i);
502 return err;
503}
504
505static struct pca9532_platform_data *
506pca9532_of_populate_pdata(struct device *dev, struct device_node *np)
507{
508 struct pca9532_platform_data *pdata;
509 int devid, maxleds;
510 int i = 0;
511 const char *state;
512
513 devid = (int)(uintptr_t)of_device_get_match_data(dev);
514 maxleds = pca9532_chip_info_tbl[devid].num_leds;
515
516 pdata = devm_kzalloc(dev, size: sizeof(*pdata), GFP_KERNEL);
517 if (!pdata)
518 return ERR_PTR(error: -ENOMEM);
519
520 pdata->gpio_base = -1;
521
522 of_property_read_u8_array(np, propname: "nxp,pwm", out_values: &pdata->pwm[PCA9532_PWM_ID_0],
523 ARRAY_SIZE(pdata->pwm));
524 of_property_read_u8_array(np, propname: "nxp,psc", out_values: &pdata->psc[PCA9532_PWM_ID_0],
525 ARRAY_SIZE(pdata->psc));
526
527 for_each_available_child_of_node_scoped(np, child) {
528 if (of_property_read_string(np: child, propname: "label",
529 out_string: &pdata->leds[i].name))
530 pdata->leds[i].name = child->name;
531 of_property_read_u32(np: child, propname: "type", out_value: &pdata->leds[i].type);
532 of_property_read_string(np: child, propname: "linux,default-trigger",
533 out_string: &pdata->leds[i].default_trigger);
534 if (!of_property_read_string(np: child, propname: "default-state", out_string: &state)) {
535 if (!strcmp(state, "on"))
536 pdata->leds[i].state = PCA9532_ON;
537 else if (!strcmp(state, "keep"))
538 pdata->leds[i].state = PCA9532_KEEP;
539 }
540 if (++i >= maxleds)
541 break;
542 }
543
544 return pdata;
545}
546
547static int pca9532_probe(struct i2c_client *client)
548{
549 const struct i2c_device_id *id = i2c_client_get_device_id(client);
550 int devid;
551 struct pca9532_data *data = i2c_get_clientdata(client);
552 struct pca9532_platform_data *pca9532_pdata =
553 dev_get_platdata(dev: &client->dev);
554 struct device_node *np = dev_of_node(dev: &client->dev);
555
556 if (!pca9532_pdata) {
557 if (np) {
558 pca9532_pdata =
559 pca9532_of_populate_pdata(dev: &client->dev, np);
560 if (IS_ERR(ptr: pca9532_pdata))
561 return PTR_ERR(ptr: pca9532_pdata);
562 } else {
563 dev_err(&client->dev, "no platform data\n");
564 return -EINVAL;
565 }
566 devid = (int)(uintptr_t)of_device_get_match_data(dev: &client->dev);
567 } else {
568 devid = id->driver_data;
569 }
570
571 if (!i2c_check_functionality(adap: client->adapter,
572 I2C_FUNC_SMBUS_BYTE_DATA))
573 return -EIO;
574
575 data = devm_kzalloc(dev: &client->dev, size: sizeof(*data), GFP_KERNEL);
576 if (!data)
577 return -ENOMEM;
578
579 data->chip_info = &pca9532_chip_info_tbl[devid];
580
581 dev_info(&client->dev, "setting platform data\n");
582 i2c_set_clientdata(client, data);
583 data->client = client;
584 mutex_init(&data->update_lock);
585
586 return pca9532_configure(client, data, pdata: pca9532_pdata);
587}
588
589static void pca9532_remove(struct i2c_client *client)
590{
591 struct pca9532_data *data = i2c_get_clientdata(client);
592
593 pca9532_destroy_devices(data, n_devs: data->chip_info->num_leds);
594}
595
596module_i2c_driver(pca9532_driver);
597
598MODULE_AUTHOR("Riku Voipio");
599MODULE_LICENSE("GPL");
600MODULE_DESCRIPTION("PCA 9532 LED dimmer");
601

source code of linux/drivers/leds/leds-pca9532.c