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 * */
pca9532_calcpwm(struct i2c_client * client,int pwm,int blink,enum led_brightness value)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
pca9532_setpwm(struct i2c_client * client,int pwm)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 */
pca9532_setled(struct pca9532_led * led)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
pca9532_set_brightness(struct led_classdev * led_cdev,enum led_brightness value)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
pca9532_update_hw_blink(struct pca9532_led * led,unsigned long delay_on,unsigned long delay_off)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
pca9532_set_blink(struct led_classdev * led_cdev,unsigned long * delay_on,unsigned long * delay_off)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
pca9532_event(struct input_dev * dev,unsigned int type,unsigned int code,int value)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
pca9532_input_work(struct work_struct * work)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
pca9532_getled(struct pca9532_led * led)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
pca9532_gpio_request_pin(struct gpio_chip * gc,unsigned offset)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
pca9532_gpio_set_value(struct gpio_chip * gc,unsigned int offset,int val)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_OFF;
331 else
332 led->state = PCA9532_ON;
333
334 pca9532_setled(led);
335
336 return 0;
337 }
338
pca9532_gpio_get_value(struct gpio_chip * gc,unsigned offset)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
pca9532_gpio_direction_input(struct gpio_chip * gc,unsigned offset)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, 1);
353
354 return 0;
355 }
356
pca9532_gpio_direction_output(struct gpio_chip * gc,unsigned offset,int val)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
pca9532_destroy_devices(struct pca9532_data * data,int n_devs)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
pca9532_configure(struct i2c_client * client,struct pca9532_data * data,struct pca9532_platform_data * pdata)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 err = i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(maxleds, i),
401 data->pwm[i]);
402 if (err < 0)
403 return err;
404 err = i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(maxleds, i),
405 data->psc[i]);
406 if (err < 0)
407 return err;
408 }
409
410 data->hw_blink = true;
411 for (i = 0; i < data->chip_info->num_leds; i++) {
412 struct pca9532_led *led = &data->leds[i];
413 struct pca9532_led *pled = &pdata->leds[i];
414 led->client = client;
415 led->id = i;
416 led->type = pled->type;
417 switch (led->type) {
418 case PCA9532_TYPE_NONE:
419 break;
420 case PCA9532_TYPE_GPIO:
421 gpios++;
422 break;
423 case PCA9532_TYPE_LED:
424 if (pled->state == PCA9532_KEEP)
425 led->state = pca9532_getled(led);
426 else
427 led->state = pled->state;
428 led->name = pled->name;
429 led->ldev.name = led->name;
430 led->ldev.default_trigger = pled->default_trigger;
431 led->ldev.brightness = LED_OFF;
432 led->ldev.brightness_set_blocking =
433 pca9532_set_brightness;
434 led->ldev.blink_set = pca9532_set_blink;
435 err = led_classdev_register(&client->dev, &led->ldev);
436 if (err < 0) {
437 dev_err(&client->dev,
438 "couldn't register LED %s\n",
439 led->name);
440 goto exit;
441 }
442 pca9532_setled(led);
443 break;
444 case PCA9532_TYPE_N2100_BEEP:
445 /* PWM1 is reserved for beeper so blink will not use hardware */
446 data->hw_blink = false;
447 BUG_ON(data->idev);
448 led->state = PCA9532_PWM1;
449 pca9532_setled(led);
450 data->idev = devm_input_allocate_device(&client->dev);
451 if (data->idev == NULL) {
452 err = -ENOMEM;
453 goto exit;
454 }
455 data->idev->name = pled->name;
456 data->idev->phys = "i2c/pca9532";
457 data->idev->id.bustype = BUS_HOST;
458 data->idev->id.vendor = 0x001f;
459 data->idev->id.product = 0x0001;
460 data->idev->id.version = 0x0100;
461 data->idev->evbit[0] = BIT_MASK(EV_SND);
462 data->idev->sndbit[0] = BIT_MASK(SND_BELL) |
463 BIT_MASK(SND_TONE);
464 data->idev->event = pca9532_event;
465 input_set_drvdata(data->idev, data);
466 INIT_WORK(&data->work, pca9532_input_work);
467 err = input_register_device(data->idev);
468 if (err) {
469 cancel_work_sync(&data->work);
470 data->idev = NULL;
471 goto exit;
472 }
473 break;
474 }
475 }
476
477 #ifdef CONFIG_LEDS_PCA9532_GPIO
478 if (gpios) {
479 data->gpio.label = "gpio-pca9532";
480 data->gpio.direction_input = pca9532_gpio_direction_input;
481 data->gpio.direction_output = pca9532_gpio_direction_output;
482 data->gpio.set = pca9532_gpio_set_value;
483 data->gpio.get = pca9532_gpio_get_value;
484 data->gpio.request = pca9532_gpio_request_pin;
485 data->gpio.can_sleep = 1;
486 data->gpio.base = pdata->gpio_base;
487 data->gpio.ngpio = data->chip_info->num_leds;
488 data->gpio.parent = &client->dev;
489 data->gpio.owner = THIS_MODULE;
490
491 err = gpiochip_add_data(&data->gpio, data);
492 if (err) {
493 /* Use data->gpio.dev as a flag for freeing gpiochip */
494 data->gpio.parent = NULL;
495 dev_warn(&client->dev, "could not add gpiochip\n");
496 } else {
497 dev_info(&client->dev, "gpios %i...%i\n",
498 data->gpio.base, data->gpio.base +
499 data->gpio.ngpio - 1);
500 }
501 }
502 #endif
503
504 return 0;
505
506 exit:
507 pca9532_destroy_devices(data, i);
508 return err;
509 }
510
511 static struct pca9532_platform_data *
pca9532_of_populate_pdata(struct device * dev,struct device_node * np)512 pca9532_of_populate_pdata(struct device *dev, struct device_node *np)
513 {
514 struct pca9532_platform_data *pdata;
515 int devid, maxleds;
516 int i = 0;
517 const char *state;
518
519 devid = (int)(uintptr_t)of_device_get_match_data(dev);
520 maxleds = pca9532_chip_info_tbl[devid].num_leds;
521
522 pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
523 if (!pdata)
524 return ERR_PTR(-ENOMEM);
525
526 pdata->gpio_base = -1;
527
528 of_property_read_u8_array(np, "nxp,pwm", &pdata->pwm[PCA9532_PWM_ID_0],
529 ARRAY_SIZE(pdata->pwm));
530 of_property_read_u8_array(np, "nxp,psc", &pdata->psc[PCA9532_PWM_ID_0],
531 ARRAY_SIZE(pdata->psc));
532
533 for_each_available_child_of_node_scoped(np, child) {
534 if (of_property_read_string(child, "label",
535 &pdata->leds[i].name))
536 pdata->leds[i].name = child->name;
537 of_property_read_u32(child, "type", &pdata->leds[i].type);
538 of_property_read_string(child, "linux,default-trigger",
539 &pdata->leds[i].default_trigger);
540 if (!of_property_read_string(child, "default-state", &state)) {
541 if (!strcmp(state, "on"))
542 pdata->leds[i].state = PCA9532_ON;
543 else if (!strcmp(state, "keep"))
544 pdata->leds[i].state = PCA9532_KEEP;
545 }
546 if (++i >= maxleds)
547 break;
548 }
549
550 return pdata;
551 }
552
pca9532_probe(struct i2c_client * client)553 static int pca9532_probe(struct i2c_client *client)
554 {
555 const struct i2c_device_id *id = i2c_client_get_device_id(client);
556 int devid;
557 struct pca9532_data *data = i2c_get_clientdata(client);
558 struct pca9532_platform_data *pca9532_pdata =
559 dev_get_platdata(&client->dev);
560 struct device_node *np = dev_of_node(&client->dev);
561
562 if (!pca9532_pdata) {
563 if (np) {
564 pca9532_pdata =
565 pca9532_of_populate_pdata(&client->dev, np);
566 if (IS_ERR(pca9532_pdata))
567 return PTR_ERR(pca9532_pdata);
568 } else {
569 dev_err(&client->dev, "no platform data\n");
570 return -EINVAL;
571 }
572 devid = (int)(uintptr_t)of_device_get_match_data(&client->dev);
573 } else {
574 devid = id->driver_data;
575 }
576
577 if (!i2c_check_functionality(client->adapter,
578 I2C_FUNC_SMBUS_BYTE_DATA))
579 return -EIO;
580
581 data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
582 if (!data)
583 return -ENOMEM;
584
585 data->chip_info = &pca9532_chip_info_tbl[devid];
586
587 dev_info(&client->dev, "setting platform data\n");
588 i2c_set_clientdata(client, data);
589 data->client = client;
590 mutex_init(&data->update_lock);
591
592 return pca9532_configure(client, data, pca9532_pdata);
593 }
594
pca9532_remove(struct i2c_client * client)595 static void pca9532_remove(struct i2c_client *client)
596 {
597 struct pca9532_data *data = i2c_get_clientdata(client);
598
599 pca9532_destroy_devices(data, data->chip_info->num_leds);
600 }
601
602 module_i2c_driver(pca9532_driver);
603
604 MODULE_AUTHOR("Riku Voipio");
605 MODULE_LICENSE("GPL");
606 MODULE_DESCRIPTION("PCA 9532 LED dimmer");
607