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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * leds-lm3533.c -- LM3533 LED driver4 *5 * Copyright (C) 2011-2012 Texas Instruments6 *7 * Author: Johan Hovold <jhovold@gmail.com>8 */9 10#include <linux/module.h>11#include <linux/leds.h>12#include <linux/mfd/core.h>13#include <linux/mutex.h>14#include <linux/platform_device.h>15#include <linux/slab.h>16 17#include <linux/mfd/lm3533.h>18 19 20#define LM3533_LVCTRLBANK_MIN 221#define LM3533_LVCTRLBANK_MAX 522#define LM3533_LVCTRLBANK_COUNT 423#define LM3533_RISEFALLTIME_MAX 724#define LM3533_ALS_CHANNEL_LV_MIN 125#define LM3533_ALS_CHANNEL_LV_MAX 226 27#define LM3533_REG_CTRLBANK_BCONF_BASE 0x1b28#define LM3533_REG_PATTERN_ENABLE 0x2829#define LM3533_REG_PATTERN_LOW_TIME_BASE 0x7130#define LM3533_REG_PATTERN_HIGH_TIME_BASE 0x7231#define LM3533_REG_PATTERN_RISETIME_BASE 0x7432#define LM3533_REG_PATTERN_FALLTIME_BASE 0x7533 34#define LM3533_REG_PATTERN_STEP 0x1035 36#define LM3533_REG_CTRLBANK_BCONF_MAPPING_MASK 0x0437#define LM3533_REG_CTRLBANK_BCONF_ALS_EN_MASK 0x0238#define LM3533_REG_CTRLBANK_BCONF_ALS_CHANNEL_MASK 0x0139 40#define LM3533_LED_FLAG_PATTERN_ENABLE 141 42 43struct lm3533_led {44 struct lm3533 *lm3533;45 struct lm3533_ctrlbank cb;46 struct led_classdev cdev;47 int id;48 49 struct mutex mutex;50 unsigned long flags;51};52 53 54static inline struct lm3533_led *to_lm3533_led(struct led_classdev *cdev)55{56 return container_of(cdev, struct lm3533_led, cdev);57}58 59static inline int lm3533_led_get_ctrlbank_id(struct lm3533_led *led)60{61 return led->id + 2;62}63 64static inline u8 lm3533_led_get_lv_reg(struct lm3533_led *led, u8 base)65{66 return base + led->id;67}68 69static inline u8 lm3533_led_get_pattern(struct lm3533_led *led)70{71 return led->id;72}73 74static inline u8 lm3533_led_get_pattern_reg(struct lm3533_led *led,75 u8 base)76{77 return base + lm3533_led_get_pattern(led) * LM3533_REG_PATTERN_STEP;78}79 80static int lm3533_led_pattern_enable(struct lm3533_led *led, int enable)81{82 u8 mask;83 u8 val;84 int pattern;85 int state;86 int ret = 0;87 88 dev_dbg(led->cdev.dev, "%s - %d\n", __func__, enable);89 90 mutex_lock(&led->mutex);91 92 state = test_bit(LM3533_LED_FLAG_PATTERN_ENABLE, &led->flags);93 if ((enable && state) || (!enable && !state))94 goto out;95 96 pattern = lm3533_led_get_pattern(led);97 mask = 1 << (2 * pattern);98 99 if (enable)100 val = mask;101 else102 val = 0;103 104 ret = lm3533_update(led->lm3533, LM3533_REG_PATTERN_ENABLE, val, mask);105 if (ret) {106 dev_err(led->cdev.dev, "failed to enable pattern %d (%d)\n",107 pattern, enable);108 goto out;109 }110 111 __change_bit(LM3533_LED_FLAG_PATTERN_ENABLE, &led->flags);112out:113 mutex_unlock(&led->mutex);114 115 return ret;116}117 118static int lm3533_led_set(struct led_classdev *cdev,119 enum led_brightness value)120{121 struct lm3533_led *led = to_lm3533_led(cdev);122 123 dev_dbg(led->cdev.dev, "%s - %d\n", __func__, value);124 125 if (value == 0)126 lm3533_led_pattern_enable(led, 0); /* disable blink */127 128 return lm3533_ctrlbank_set_brightness(&led->cb, value);129}130 131static enum led_brightness lm3533_led_get(struct led_classdev *cdev)132{133 struct lm3533_led *led = to_lm3533_led(cdev);134 u8 val;135 int ret;136 137 ret = lm3533_ctrlbank_get_brightness(&led->cb, &val);138 if (ret)139 return ret;140 141 dev_dbg(led->cdev.dev, "%s - %u\n", __func__, val);142 143 return val;144}145 146/* Pattern generator defines (delays in us). */147#define LM3533_LED_DELAY1_VMIN 0x00148#define LM3533_LED_DELAY2_VMIN 0x3d149#define LM3533_LED_DELAY3_VMIN 0x80150 151#define LM3533_LED_DELAY1_VMAX (LM3533_LED_DELAY2_VMIN - 1)152#define LM3533_LED_DELAY2_VMAX (LM3533_LED_DELAY3_VMIN - 1)153#define LM3533_LED_DELAY3_VMAX 0xff154 155#define LM3533_LED_DELAY1_TMIN 16384U156#define LM3533_LED_DELAY2_TMIN 1130496U157#define LM3533_LED_DELAY3_TMIN 10305536U158 159#define LM3533_LED_DELAY1_TMAX 999424U160#define LM3533_LED_DELAY2_TMAX 9781248U161#define LM3533_LED_DELAY3_TMAX 76890112U162 163/* t_step = (t_max - t_min) / (v_max - v_min) */164#define LM3533_LED_DELAY1_TSTEP 16384165#define LM3533_LED_DELAY2_TSTEP 131072166#define LM3533_LED_DELAY3_TSTEP 524288167 168/* Delay limits for hardware accelerated blinking (in ms). */169#define LM3533_LED_DELAY_ON_MAX \170 ((LM3533_LED_DELAY2_TMAX + LM3533_LED_DELAY2_TSTEP / 2) / 1000)171#define LM3533_LED_DELAY_OFF_MAX \172 ((LM3533_LED_DELAY3_TMAX + LM3533_LED_DELAY3_TSTEP / 2) / 1000)173 174/*175 * Returns linear map of *t from [t_min,t_max] to [v_min,v_max] with a step176 * size of t_step, where177 *178 * t_step = (t_max - t_min) / (v_max - v_min)179 *180 * and updates *t to reflect the mapped value.181 */182static u8 time_to_val(unsigned *t, unsigned t_min, unsigned t_step,183 u8 v_min, u8 v_max)184{185 unsigned val;186 187 val = (*t + t_step / 2 - t_min) / t_step + v_min;188 189 *t = t_step * (val - v_min) + t_min;190 191 return (u8)val;192}193 194/*195 * Returns time code corresponding to *delay (in ms) and updates *delay to196 * reflect actual hardware delay.197 *198 * Hardware supports 256 discrete delay times, divided into three groups with199 * the following ranges and step-sizes:200 *201 * [ 16, 999] [0x00, 0x3e] step 16 ms202 * [ 1130, 9781] [0x3d, 0x7f] step 131 ms203 * [10306, 76890] [0x80, 0xff] step 524 ms204 *205 * Note that delay group 3 is only available for delay_off.206 */207static u8 lm3533_led_get_hw_delay(unsigned *delay)208{209 unsigned t;210 u8 val;211 212 t = *delay * 1000;213 214 if (t >= (LM3533_LED_DELAY2_TMAX + LM3533_LED_DELAY3_TMIN) / 2) {215 t = clamp(t, LM3533_LED_DELAY3_TMIN, LM3533_LED_DELAY3_TMAX);216 val = time_to_val(&t, LM3533_LED_DELAY3_TMIN,217 LM3533_LED_DELAY3_TSTEP,218 LM3533_LED_DELAY3_VMIN,219 LM3533_LED_DELAY3_VMAX);220 } else if (t >= (LM3533_LED_DELAY1_TMAX + LM3533_LED_DELAY2_TMIN) / 2) {221 t = clamp(t, LM3533_LED_DELAY2_TMIN, LM3533_LED_DELAY2_TMAX);222 val = time_to_val(&t, LM3533_LED_DELAY2_TMIN,223 LM3533_LED_DELAY2_TSTEP,224 LM3533_LED_DELAY2_VMIN,225 LM3533_LED_DELAY2_VMAX);226 } else {227 t = clamp(t, LM3533_LED_DELAY1_TMIN, LM3533_LED_DELAY1_TMAX);228 val = time_to_val(&t, LM3533_LED_DELAY1_TMIN,229 LM3533_LED_DELAY1_TSTEP,230 LM3533_LED_DELAY1_VMIN,231 LM3533_LED_DELAY1_VMAX);232 }233 234 *delay = (t + 500) / 1000;235 236 return val;237}238 239/*240 * Set delay register base to *delay (in ms) and update *delay to reflect241 * actual hardware delay used.242 */243static u8 lm3533_led_delay_set(struct lm3533_led *led, u8 base,244 unsigned long *delay)245{246 unsigned t;247 u8 val;248 u8 reg;249 int ret;250 251 t = (unsigned)*delay;252 253 /* Delay group 3 is only available for low time (delay off). */254 if (base != LM3533_REG_PATTERN_LOW_TIME_BASE)255 t = min(t, LM3533_LED_DELAY2_TMAX / 1000);256 257 val = lm3533_led_get_hw_delay(&t);258 259 dev_dbg(led->cdev.dev, "%s - %lu: %u (0x%02x)\n", __func__,260 *delay, t, val);261 reg = lm3533_led_get_pattern_reg(led, base);262 ret = lm3533_write(led->lm3533, reg, val);263 if (ret)264 dev_err(led->cdev.dev, "failed to set delay (%02x)\n", reg);265 266 *delay = t;267 268 return ret;269}270 271static int lm3533_led_delay_on_set(struct lm3533_led *led, unsigned long *t)272{273 return lm3533_led_delay_set(led, LM3533_REG_PATTERN_HIGH_TIME_BASE, t);274}275 276static int lm3533_led_delay_off_set(struct lm3533_led *led, unsigned long *t)277{278 return lm3533_led_delay_set(led, LM3533_REG_PATTERN_LOW_TIME_BASE, t);279}280 281static int lm3533_led_blink_set(struct led_classdev *cdev,282 unsigned long *delay_on,283 unsigned long *delay_off)284{285 struct lm3533_led *led = to_lm3533_led(cdev);286 int ret;287 288 dev_dbg(led->cdev.dev, "%s - on = %lu, off = %lu\n", __func__,289 *delay_on, *delay_off);290 291 if (*delay_on > LM3533_LED_DELAY_ON_MAX ||292 *delay_off > LM3533_LED_DELAY_OFF_MAX)293 return -EINVAL;294 295 if (*delay_on == 0 && *delay_off == 0) {296 *delay_on = 500;297 *delay_off = 500;298 }299 300 ret = lm3533_led_delay_on_set(led, delay_on);301 if (ret)302 return ret;303 304 ret = lm3533_led_delay_off_set(led, delay_off);305 if (ret)306 return ret;307 308 return lm3533_led_pattern_enable(led, 1);309}310 311static ssize_t show_id(struct device *dev,312 struct device_attribute *attr, char *buf)313{314 struct led_classdev *led_cdev = dev_get_drvdata(dev);315 struct lm3533_led *led = to_lm3533_led(led_cdev);316 317 return sysfs_emit(buf, "%d\n", led->id);318}319 320/*321 * Pattern generator rise/fall times:322 *323 * 0 - 2048 us (default)324 * 1 - 262 ms325 * 2 - 524 ms326 * 3 - 1.049 s327 * 4 - 2.097 s328 * 5 - 4.194 s329 * 6 - 8.389 s330 * 7 - 16.78 s331 */332static ssize_t show_risefalltime(struct device *dev,333 struct device_attribute *attr,334 char *buf, u8 base)335{336 struct led_classdev *led_cdev = dev_get_drvdata(dev);337 struct lm3533_led *led = to_lm3533_led(led_cdev);338 ssize_t ret;339 u8 reg;340 u8 val;341 342 reg = lm3533_led_get_pattern_reg(led, base);343 ret = lm3533_read(led->lm3533, reg, &val);344 if (ret)345 return ret;346 347 return sysfs_emit(buf, "%x\n", val);348}349 350static ssize_t show_risetime(struct device *dev,351 struct device_attribute *attr, char *buf)352{353 return show_risefalltime(dev, attr, buf,354 LM3533_REG_PATTERN_RISETIME_BASE);355}356 357static ssize_t show_falltime(struct device *dev,358 struct device_attribute *attr, char *buf)359{360 return show_risefalltime(dev, attr, buf,361 LM3533_REG_PATTERN_FALLTIME_BASE);362}363 364static ssize_t store_risefalltime(struct device *dev,365 struct device_attribute *attr,366 const char *buf, size_t len, u8 base)367{368 struct led_classdev *led_cdev = dev_get_drvdata(dev);369 struct lm3533_led *led = to_lm3533_led(led_cdev);370 u8 val;371 u8 reg;372 int ret;373 374 if (kstrtou8(buf, 0, &val) || val > LM3533_RISEFALLTIME_MAX)375 return -EINVAL;376 377 reg = lm3533_led_get_pattern_reg(led, base);378 ret = lm3533_write(led->lm3533, reg, val);379 if (ret)380 return ret;381 382 return len;383}384 385static ssize_t store_risetime(struct device *dev,386 struct device_attribute *attr,387 const char *buf, size_t len)388{389 return store_risefalltime(dev, attr, buf, len,390 LM3533_REG_PATTERN_RISETIME_BASE);391}392 393static ssize_t store_falltime(struct device *dev,394 struct device_attribute *attr,395 const char *buf, size_t len)396{397 return store_risefalltime(dev, attr, buf, len,398 LM3533_REG_PATTERN_FALLTIME_BASE);399}400 401static ssize_t show_als_channel(struct device *dev,402 struct device_attribute *attr, char *buf)403{404 struct led_classdev *led_cdev = dev_get_drvdata(dev);405 struct lm3533_led *led = to_lm3533_led(led_cdev);406 unsigned channel;407 u8 reg;408 u8 val;409 int ret;410 411 reg = lm3533_led_get_lv_reg(led, LM3533_REG_CTRLBANK_BCONF_BASE);412 ret = lm3533_read(led->lm3533, reg, &val);413 if (ret)414 return ret;415 416 channel = (val & LM3533_REG_CTRLBANK_BCONF_ALS_CHANNEL_MASK) + 1;417 418 return sysfs_emit(buf, "%u\n", channel);419}420 421static ssize_t store_als_channel(struct device *dev,422 struct device_attribute *attr,423 const char *buf, size_t len)424{425 struct led_classdev *led_cdev = dev_get_drvdata(dev);426 struct lm3533_led *led = to_lm3533_led(led_cdev);427 unsigned channel;428 u8 reg;429 u8 val;430 u8 mask;431 int ret;432 433 if (kstrtouint(buf, 0, &channel))434 return -EINVAL;435 436 if (channel < LM3533_ALS_CHANNEL_LV_MIN ||437 channel > LM3533_ALS_CHANNEL_LV_MAX)438 return -EINVAL;439 440 reg = lm3533_led_get_lv_reg(led, LM3533_REG_CTRLBANK_BCONF_BASE);441 mask = LM3533_REG_CTRLBANK_BCONF_ALS_CHANNEL_MASK;442 val = channel - 1;443 444 ret = lm3533_update(led->lm3533, reg, val, mask);445 if (ret)446 return ret;447 448 return len;449}450 451static ssize_t show_als_en(struct device *dev,452 struct device_attribute *attr, char *buf)453{454 struct led_classdev *led_cdev = dev_get_drvdata(dev);455 struct lm3533_led *led = to_lm3533_led(led_cdev);456 bool enable;457 u8 reg;458 u8 val;459 int ret;460 461 reg = lm3533_led_get_lv_reg(led, LM3533_REG_CTRLBANK_BCONF_BASE);462 ret = lm3533_read(led->lm3533, reg, &val);463 if (ret)464 return ret;465 466 enable = val & LM3533_REG_CTRLBANK_BCONF_ALS_EN_MASK;467 468 return sysfs_emit(buf, "%d\n", enable);469}470 471static ssize_t store_als_en(struct device *dev,472 struct device_attribute *attr,473 const char *buf, size_t len)474{475 struct led_classdev *led_cdev = dev_get_drvdata(dev);476 struct lm3533_led *led = to_lm3533_led(led_cdev);477 unsigned enable;478 u8 reg;479 u8 mask;480 u8 val;481 int ret;482 483 if (kstrtouint(buf, 0, &enable))484 return -EINVAL;485 486 reg = lm3533_led_get_lv_reg(led, LM3533_REG_CTRLBANK_BCONF_BASE);487 mask = LM3533_REG_CTRLBANK_BCONF_ALS_EN_MASK;488 489 if (enable)490 val = mask;491 else492 val = 0;493 494 ret = lm3533_update(led->lm3533, reg, val, mask);495 if (ret)496 return ret;497 498 return len;499}500 501static ssize_t show_linear(struct device *dev,502 struct device_attribute *attr, char *buf)503{504 struct led_classdev *led_cdev = dev_get_drvdata(dev);505 struct lm3533_led *led = to_lm3533_led(led_cdev);506 u8 reg;507 u8 val;508 int linear;509 int ret;510 511 reg = lm3533_led_get_lv_reg(led, LM3533_REG_CTRLBANK_BCONF_BASE);512 ret = lm3533_read(led->lm3533, reg, &val);513 if (ret)514 return ret;515 516 if (val & LM3533_REG_CTRLBANK_BCONF_MAPPING_MASK)517 linear = 1;518 else519 linear = 0;520 521 return sysfs_emit(buf, "%x\n", linear);522}523 524static ssize_t store_linear(struct device *dev,525 struct device_attribute *attr,526 const char *buf, size_t len)527{528 struct led_classdev *led_cdev = dev_get_drvdata(dev);529 struct lm3533_led *led = to_lm3533_led(led_cdev);530 unsigned long linear;531 u8 reg;532 u8 mask;533 u8 val;534 int ret;535 536 if (kstrtoul(buf, 0, &linear))537 return -EINVAL;538 539 reg = lm3533_led_get_lv_reg(led, LM3533_REG_CTRLBANK_BCONF_BASE);540 mask = LM3533_REG_CTRLBANK_BCONF_MAPPING_MASK;541 542 if (linear)543 val = mask;544 else545 val = 0;546 547 ret = lm3533_update(led->lm3533, reg, val, mask);548 if (ret)549 return ret;550 551 return len;552}553 554static ssize_t show_pwm(struct device *dev,555 struct device_attribute *attr,556 char *buf)557{558 struct led_classdev *led_cdev = dev_get_drvdata(dev);559 struct lm3533_led *led = to_lm3533_led(led_cdev);560 u8 val;561 int ret;562 563 ret = lm3533_ctrlbank_get_pwm(&led->cb, &val);564 if (ret)565 return ret;566 567 return sysfs_emit(buf, "%u\n", val);568}569 570static ssize_t store_pwm(struct device *dev,571 struct device_attribute *attr,572 const char *buf, size_t len)573{574 struct led_classdev *led_cdev = dev_get_drvdata(dev);575 struct lm3533_led *led = to_lm3533_led(led_cdev);576 u8 val;577 int ret;578 579 if (kstrtou8(buf, 0, &val))580 return -EINVAL;581 582 ret = lm3533_ctrlbank_set_pwm(&led->cb, val);583 if (ret)584 return ret;585 586 return len;587}588 589static LM3533_ATTR_RW(als_channel);590static LM3533_ATTR_RW(als_en);591static LM3533_ATTR_RW(falltime);592static LM3533_ATTR_RO(id);593static LM3533_ATTR_RW(linear);594static LM3533_ATTR_RW(pwm);595static LM3533_ATTR_RW(risetime);596 597static struct attribute *lm3533_led_attributes[] = {598 &dev_attr_als_channel.attr,599 &dev_attr_als_en.attr,600 &dev_attr_falltime.attr,601 &dev_attr_id.attr,602 &dev_attr_linear.attr,603 &dev_attr_pwm.attr,604 &dev_attr_risetime.attr,605 NULL,606};607 608static umode_t lm3533_led_attr_is_visible(struct kobject *kobj,609 struct attribute *attr, int n)610{611 struct device *dev = kobj_to_dev(kobj);612 struct led_classdev *led_cdev = dev_get_drvdata(dev);613 struct lm3533_led *led = to_lm3533_led(led_cdev);614 umode_t mode = attr->mode;615 616 if (attr == &dev_attr_als_channel.attr ||617 attr == &dev_attr_als_en.attr) {618 if (!led->lm3533->have_als)619 mode = 0;620 }621 622 return mode;623};624 625static const struct attribute_group lm3533_led_attribute_group = {626 .is_visible = lm3533_led_attr_is_visible,627 .attrs = lm3533_led_attributes628};629 630static const struct attribute_group *lm3533_led_attribute_groups[] = {631 &lm3533_led_attribute_group,632 NULL633};634 635static int lm3533_led_setup(struct lm3533_led *led,636 struct lm3533_led_platform_data *pdata)637{638 int ret;639 640 ret = lm3533_ctrlbank_set_max_current(&led->cb, pdata->max_current);641 if (ret)642 return ret;643 644 return lm3533_ctrlbank_set_pwm(&led->cb, pdata->pwm);645}646 647static int lm3533_led_probe(struct platform_device *pdev)648{649 struct lm3533 *lm3533;650 struct lm3533_led_platform_data *pdata;651 struct lm3533_led *led;652 int ret;653 654 dev_dbg(&pdev->dev, "%s\n", __func__);655 656 lm3533 = dev_get_drvdata(pdev->dev.parent);657 if (!lm3533)658 return -EINVAL;659 660 pdata = dev_get_platdata(&pdev->dev);661 if (!pdata) {662 dev_err(&pdev->dev, "no platform data\n");663 return -EINVAL;664 }665 666 if (pdev->id < 0 || pdev->id >= LM3533_LVCTRLBANK_COUNT) {667 dev_err(&pdev->dev, "illegal LED id %d\n", pdev->id);668 return -EINVAL;669 }670 671 led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);672 if (!led)673 return -ENOMEM;674 675 led->lm3533 = lm3533;676 led->cdev.name = pdata->name;677 led->cdev.default_trigger = pdata->default_trigger;678 led->cdev.brightness_set_blocking = lm3533_led_set;679 led->cdev.brightness_get = lm3533_led_get;680 led->cdev.blink_set = lm3533_led_blink_set;681 led->cdev.brightness = LED_OFF;682 led->cdev.groups = lm3533_led_attribute_groups;683 led->id = pdev->id;684 685 mutex_init(&led->mutex);686 687 /* The class framework makes a callback to get brightness during688 * registration so use parent device (for error reporting) until689 * registered.690 */691 led->cb.lm3533 = lm3533;692 led->cb.id = lm3533_led_get_ctrlbank_id(led);693 led->cb.dev = lm3533->dev;694 695 platform_set_drvdata(pdev, led);696 697 ret = led_classdev_register(pdev->dev.parent, &led->cdev);698 if (ret) {699 dev_err(&pdev->dev, "failed to register LED %d\n", pdev->id);700 return ret;701 }702 703 led->cb.dev = led->cdev.dev;704 705 ret = lm3533_led_setup(led, pdata);706 if (ret)707 goto err_deregister;708 709 ret = lm3533_ctrlbank_enable(&led->cb);710 if (ret)711 goto err_deregister;712 713 return 0;714 715err_deregister:716 led_classdev_unregister(&led->cdev);717 718 return ret;719}720 721static void lm3533_led_remove(struct platform_device *pdev)722{723 struct lm3533_led *led = platform_get_drvdata(pdev);724 725 dev_dbg(&pdev->dev, "%s\n", __func__);726 727 lm3533_ctrlbank_disable(&led->cb);728 led_classdev_unregister(&led->cdev);729}730 731static void lm3533_led_shutdown(struct platform_device *pdev)732{733 734 struct lm3533_led *led = platform_get_drvdata(pdev);735 736 dev_dbg(&pdev->dev, "%s\n", __func__);737 738 lm3533_ctrlbank_disable(&led->cb);739 lm3533_led_set(&led->cdev, LED_OFF); /* disable blink */740}741 742static struct platform_driver lm3533_led_driver = {743 .driver = {744 .name = "lm3533-leds",745 },746 .probe = lm3533_led_probe,747 .remove_new = lm3533_led_remove,748 .shutdown = lm3533_led_shutdown,749};750module_platform_driver(lm3533_led_driver);751 752MODULE_AUTHOR("Johan Hovold <jhovold@gmail.com>");753MODULE_DESCRIPTION("LM3533 LED driver");754MODULE_LICENSE("GPL");755MODULE_ALIAS("platform:lm3533-leds");756