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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * lm3533-bl.c -- LM3533 Backlight 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/init.h>12#include <linux/platform_device.h>13#include <linux/backlight.h>14#include <linux/slab.h>15 16#include <linux/mfd/lm3533.h>17 18 19#define LM3533_HVCTRLBANK_COUNT 220#define LM3533_BL_MAX_BRIGHTNESS 25521 22#define LM3533_REG_CTRLBANK_AB_BCONF 0x1a23 24 25struct lm3533_bl {26 struct lm3533 *lm3533;27 struct lm3533_ctrlbank cb;28 struct backlight_device *bd;29 int id;30};31 32 33static inline int lm3533_bl_get_ctrlbank_id(struct lm3533_bl *bl)34{35 return bl->id;36}37 38static int lm3533_bl_update_status(struct backlight_device *bd)39{40 struct lm3533_bl *bl = bl_get_data(bd);41 42 return lm3533_ctrlbank_set_brightness(&bl->cb, backlight_get_brightness(bd));43}44 45static int lm3533_bl_get_brightness(struct backlight_device *bd)46{47 struct lm3533_bl *bl = bl_get_data(bd);48 u8 val;49 int ret;50 51 ret = lm3533_ctrlbank_get_brightness(&bl->cb, &val);52 if (ret)53 return ret;54 55 return val;56}57 58static const struct backlight_ops lm3533_bl_ops = {59 .get_brightness = lm3533_bl_get_brightness,60 .update_status = lm3533_bl_update_status,61};62 63static ssize_t show_id(struct device *dev,64 struct device_attribute *attr, char *buf)65{66 struct lm3533_bl *bl = dev_get_drvdata(dev);67 68 return scnprintf(buf, PAGE_SIZE, "%d\n", bl->id);69}70 71static ssize_t show_als_channel(struct device *dev,72 struct device_attribute *attr, char *buf)73{74 struct lm3533_bl *bl = dev_get_drvdata(dev);75 unsigned channel = lm3533_bl_get_ctrlbank_id(bl);76 77 return scnprintf(buf, PAGE_SIZE, "%u\n", channel);78}79 80static ssize_t show_als_en(struct device *dev,81 struct device_attribute *attr, char *buf)82{83 struct lm3533_bl *bl = dev_get_drvdata(dev);84 int ctrlbank = lm3533_bl_get_ctrlbank_id(bl);85 u8 val;86 u8 mask;87 bool enable;88 int ret;89 90 ret = lm3533_read(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, &val);91 if (ret)92 return ret;93 94 mask = 1 << (2 * ctrlbank);95 enable = val & mask;96 97 return scnprintf(buf, PAGE_SIZE, "%d\n", enable);98}99 100static ssize_t store_als_en(struct device *dev,101 struct device_attribute *attr,102 const char *buf, size_t len)103{104 struct lm3533_bl *bl = dev_get_drvdata(dev);105 int ctrlbank = lm3533_bl_get_ctrlbank_id(bl);106 int enable;107 u8 val;108 u8 mask;109 int ret;110 111 if (kstrtoint(buf, 0, &enable))112 return -EINVAL;113 114 mask = 1 << (2 * ctrlbank);115 116 if (enable)117 val = mask;118 else119 val = 0;120 121 ret = lm3533_update(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, val,122 mask);123 if (ret)124 return ret;125 126 return len;127}128 129static ssize_t show_linear(struct device *dev,130 struct device_attribute *attr, char *buf)131{132 struct lm3533_bl *bl = dev_get_drvdata(dev);133 u8 val;134 u8 mask;135 int linear;136 int ret;137 138 ret = lm3533_read(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, &val);139 if (ret)140 return ret;141 142 mask = 1 << (2 * lm3533_bl_get_ctrlbank_id(bl) + 1);143 144 if (val & mask)145 linear = 1;146 else147 linear = 0;148 149 return scnprintf(buf, PAGE_SIZE, "%x\n", linear);150}151 152static ssize_t store_linear(struct device *dev,153 struct device_attribute *attr,154 const char *buf, size_t len)155{156 struct lm3533_bl *bl = dev_get_drvdata(dev);157 unsigned long linear;158 u8 mask;159 u8 val;160 int ret;161 162 if (kstrtoul(buf, 0, &linear))163 return -EINVAL;164 165 mask = 1 << (2 * lm3533_bl_get_ctrlbank_id(bl) + 1);166 167 if (linear)168 val = mask;169 else170 val = 0;171 172 ret = lm3533_update(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, val,173 mask);174 if (ret)175 return ret;176 177 return len;178}179 180static ssize_t show_pwm(struct device *dev,181 struct device_attribute *attr,182 char *buf)183{184 struct lm3533_bl *bl = dev_get_drvdata(dev);185 u8 val;186 int ret;187 188 ret = lm3533_ctrlbank_get_pwm(&bl->cb, &val);189 if (ret)190 return ret;191 192 return scnprintf(buf, PAGE_SIZE, "%u\n", val);193}194 195static ssize_t store_pwm(struct device *dev,196 struct device_attribute *attr,197 const char *buf, size_t len)198{199 struct lm3533_bl *bl = dev_get_drvdata(dev);200 u8 val;201 int ret;202 203 if (kstrtou8(buf, 0, &val))204 return -EINVAL;205 206 ret = lm3533_ctrlbank_set_pwm(&bl->cb, val);207 if (ret)208 return ret;209 210 return len;211}212 213static LM3533_ATTR_RO(als_channel);214static LM3533_ATTR_RW(als_en);215static LM3533_ATTR_RO(id);216static LM3533_ATTR_RW(linear);217static LM3533_ATTR_RW(pwm);218 219static struct attribute *lm3533_bl_attributes[] = {220 &dev_attr_als_channel.attr,221 &dev_attr_als_en.attr,222 &dev_attr_id.attr,223 &dev_attr_linear.attr,224 &dev_attr_pwm.attr,225 NULL,226};227 228static umode_t lm3533_bl_attr_is_visible(struct kobject *kobj,229 struct attribute *attr, int n)230{231 struct device *dev = kobj_to_dev(kobj);232 struct lm3533_bl *bl = dev_get_drvdata(dev);233 umode_t mode = attr->mode;234 235 if (attr == &dev_attr_als_channel.attr ||236 attr == &dev_attr_als_en.attr) {237 if (!bl->lm3533->have_als)238 mode = 0;239 }240 241 return mode;242};243 244static struct attribute_group lm3533_bl_attribute_group = {245 .is_visible = lm3533_bl_attr_is_visible,246 .attrs = lm3533_bl_attributes247};248 249static int lm3533_bl_setup(struct lm3533_bl *bl,250 struct lm3533_bl_platform_data *pdata)251{252 int ret;253 254 ret = lm3533_ctrlbank_set_max_current(&bl->cb, pdata->max_current);255 if (ret)256 return ret;257 258 return lm3533_ctrlbank_set_pwm(&bl->cb, pdata->pwm);259}260 261static int lm3533_bl_probe(struct platform_device *pdev)262{263 struct lm3533 *lm3533;264 struct lm3533_bl_platform_data *pdata;265 struct lm3533_bl *bl;266 struct backlight_device *bd;267 struct backlight_properties props;268 int ret;269 270 dev_dbg(&pdev->dev, "%s\n", __func__);271 272 lm3533 = dev_get_drvdata(pdev->dev.parent);273 if (!lm3533)274 return -EINVAL;275 276 pdata = dev_get_platdata(&pdev->dev);277 if (!pdata) {278 dev_err(&pdev->dev, "no platform data\n");279 return -EINVAL;280 }281 282 if (pdev->id < 0 || pdev->id >= LM3533_HVCTRLBANK_COUNT) {283 dev_err(&pdev->dev, "illegal backlight id %d\n", pdev->id);284 return -EINVAL;285 }286 287 bl = devm_kzalloc(&pdev->dev, sizeof(*bl), GFP_KERNEL);288 if (!bl)289 return -ENOMEM;290 291 bl->lm3533 = lm3533;292 bl->id = pdev->id;293 294 bl->cb.lm3533 = lm3533;295 bl->cb.id = lm3533_bl_get_ctrlbank_id(bl);296 bl->cb.dev = NULL; /* until registered */297 298 memset(&props, 0, sizeof(props));299 props.type = BACKLIGHT_RAW;300 props.max_brightness = LM3533_BL_MAX_BRIGHTNESS;301 props.brightness = pdata->default_brightness;302 bd = devm_backlight_device_register(&pdev->dev, pdata->name,303 pdev->dev.parent, bl, &lm3533_bl_ops,304 &props);305 if (IS_ERR(bd)) {306 dev_err(&pdev->dev, "failed to register backlight device\n");307 return PTR_ERR(bd);308 }309 310 bl->bd = bd;311 bl->cb.dev = &bl->bd->dev;312 313 platform_set_drvdata(pdev, bl);314 315 ret = sysfs_create_group(&bd->dev.kobj, &lm3533_bl_attribute_group);316 if (ret < 0) {317 dev_err(&pdev->dev, "failed to create sysfs attributes\n");318 return ret;319 }320 321 backlight_update_status(bd);322 323 ret = lm3533_bl_setup(bl, pdata);324 if (ret)325 goto err_sysfs_remove;326 327 ret = lm3533_ctrlbank_enable(&bl->cb);328 if (ret)329 goto err_sysfs_remove;330 331 return 0;332 333err_sysfs_remove:334 sysfs_remove_group(&bd->dev.kobj, &lm3533_bl_attribute_group);335 336 return ret;337}338 339static void lm3533_bl_remove(struct platform_device *pdev)340{341 struct lm3533_bl *bl = platform_get_drvdata(pdev);342 struct backlight_device *bd = bl->bd;343 344 dev_dbg(&bd->dev, "%s\n", __func__);345 346 bd->props.power = BACKLIGHT_POWER_OFF;347 bd->props.brightness = 0;348 349 lm3533_ctrlbank_disable(&bl->cb);350 sysfs_remove_group(&bd->dev.kobj, &lm3533_bl_attribute_group);351}352 353#ifdef CONFIG_PM_SLEEP354static int lm3533_bl_suspend(struct device *dev)355{356 struct lm3533_bl *bl = dev_get_drvdata(dev);357 358 dev_dbg(dev, "%s\n", __func__);359 360 return lm3533_ctrlbank_disable(&bl->cb);361}362 363static int lm3533_bl_resume(struct device *dev)364{365 struct lm3533_bl *bl = dev_get_drvdata(dev);366 367 dev_dbg(dev, "%s\n", __func__);368 369 return lm3533_ctrlbank_enable(&bl->cb);370}371#endif372 373static SIMPLE_DEV_PM_OPS(lm3533_bl_pm_ops, lm3533_bl_suspend, lm3533_bl_resume);374 375static void lm3533_bl_shutdown(struct platform_device *pdev)376{377 struct lm3533_bl *bl = platform_get_drvdata(pdev);378 379 dev_dbg(&pdev->dev, "%s\n", __func__);380 381 lm3533_ctrlbank_disable(&bl->cb);382}383 384static struct platform_driver lm3533_bl_driver = {385 .driver = {386 .name = "lm3533-backlight",387 .pm = &lm3533_bl_pm_ops,388 },389 .probe = lm3533_bl_probe,390 .remove_new = lm3533_bl_remove,391 .shutdown = lm3533_bl_shutdown,392};393module_platform_driver(lm3533_bl_driver);394 395MODULE_AUTHOR("Johan Hovold <jhovold@gmail.com>");396MODULE_DESCRIPTION("LM3533 Backlight driver");397MODULE_LICENSE("GPL");398MODULE_ALIAS("platform:lm3533-backlight");399