drivers/video/backlight/adp5520_bl.c

   1 /*
   2  * Backlight driver for Analog Devices ADP5520/ADP5501 MFD PMICs
   3  *
   4  * Copyright 2009 Analog Devices Inc.
   5  *
   6  * Licensed under the GPL-2 or later.
   7  */
   8
   9 #include <linux/kernel.h>
  10 #include <linux/init.h>
  11 #include <linux/platform_device.h>
  12 #include <linux/fb.h>
  13 #include <linux/backlight.h>
  14 #include <linux/mfd/adp5520.h>
  15 #include <linux/slab.h>
  16 #include <linux/module.h>
  17
  18 struct adp5520_bl {
  19         struct device *master;
  20         struct adp5520_backlight_platform_data *pdata;
  21         struct mutex lock;
  22         unsigned long cached_daylight_max;
  23         int id;
  24         int current_brightness;
  25 };
  26
  27 static int adp5520_bl_set(struct backlight_device *bl, int brightness)
  28 {
  29         struct adp5520_bl *data = bl_get_data(bl);
  30         struct device *master = data->master;
  31         int ret = 0;
  32
  33         if (data->pdata->en_ambl_sens) {
  34                 if ((brightness > 0) && (brightness < ADP5020_MAX_BRIGHTNESS)) {
  35                         /* Disable Ambient Light auto adjust */
  36                         ret |= adp5520_clr_bits(master, ADP5520_BL_CONTROL,
  37                                         ADP5520_BL_AUTO_ADJ);
  38                         ret |= adp5520_write(master, ADP5520_DAYLIGHT_MAX,
  39                                         brightness);
  40                 } else {
  41                         /*
  42                          * MAX_BRIGHTNESS -> Enable Ambient Light auto adjust
  43                          * restore daylight l3 sysfs brightness
  44                          */
  45                         ret |= adp5520_write(master, ADP5520_DAYLIGHT_MAX,
  46                                          data->cached_daylight_max);
  47                         ret |= adp5520_set_bits(master, ADP5520_BL_CONTROL,
  48                                          ADP5520_BL_AUTO_ADJ);
  49                 }
  50         } else {
  51                 ret |= adp5520_write(master, ADP5520_DAYLIGHT_MAX, brightness);
  52         }
  53
  54         if (data->current_brightness && brightness == 0)
  55                 ret |= adp5520_set_bits(master,
  56                                 ADP5520_MODE_STATUS, ADP5520_DIM_EN);
  57         else if (data->current_brightness == 0 && brightness)
  58                 ret |= adp5520_clr_bits(master,
  59                                 ADP5520_MODE_STATUS, ADP5520_DIM_EN);
  60
  61         if (!ret)
  62                 data->current_brightness = brightness;
  63
  64         return ret;
  65 }
  66
  67 static int adp5520_bl_update_status(struct backlight_device *bl)
  68 {
  69         int brightness = bl->props.brightness;
  70         if (bl->props.power != FB_BLANK_UNBLANK)
  71                 brightness = 0;
  72
  73         if (bl->props.fb_blank != FB_BLANK_UNBLANK)
  74                 brightness = 0;
  75
  76         return adp5520_bl_set(bl, brightness);
  77 }
  78
  79 static int adp5520_bl_get_brightness(struct backlight_device *bl)
  80 {
  81         struct adp5520_bl *data = bl_get_data(bl);
  82         int error;
  83         uint8_t reg_val;
  84
  85         error = adp5520_read(data->master, ADP5520_BL_VALUE, &reg_val);
  86
  87         return error ? data->current_brightness : reg_val;
  88 }
  89
  90 static const struct backlight_ops adp5520_bl_ops = {
  91         .update_status  = adp5520_bl_update_status,
  92         .get_brightness = adp5520_bl_get_brightness,
  93 };
  94
  95 static int adp5520_bl_setup(struct backlight_device *bl)
  96 {
  97         struct adp5520_bl *data = bl_get_data(bl);
  98         struct device *master = data->master;
  99         struct adp5520_backlight_platform_data *pdata = data->pdata;
 100         int ret = 0;
 101
 102         ret |= adp5520_write(master, ADP5520_DAYLIGHT_MAX,
 103                                 pdata->l1_daylight_max);
 104         ret |= adp5520_write(master, ADP5520_DAYLIGHT_DIM,
 105                                 pdata->l1_daylight_dim);
 106
 107         if (pdata->en_ambl_sens) {
 108                 data->cached_daylight_max = pdata->l1_daylight_max;
 109                 ret |= adp5520_write(master, ADP5520_OFFICE_MAX,
 110                                 pdata->l2_office_max);
 111                 ret |= adp5520_write(master, ADP5520_OFFICE_DIM,
 112                                 pdata->l2_office_dim);
 113                 ret |= adp5520_write(master, ADP5520_DARK_MAX,
 114                                 pdata->l3_dark_max);
 115                 ret |= adp5520_write(master, ADP5520_DARK_DIM,
 116                                 pdata->l3_dark_dim);
 117                 ret |= adp5520_write(master, ADP5520_L2_TRIP,
 118                                 pdata->l2_trip);
 119                 ret |= adp5520_write(master, ADP5520_L2_HYS,
 120                                 pdata->l2_hyst);
 121                 ret |= adp5520_write(master, ADP5520_L3_TRIP,
 122                                  pdata->l3_trip);
 123                 ret |= adp5520_write(master, ADP5520_L3_HYS,
 124                                 pdata->l3_hyst);
 125                 ret |= adp5520_write(master, ADP5520_ALS_CMPR_CFG,
 126                                 ALS_CMPR_CFG_VAL(pdata->abml_filt,
 127                                 ADP5520_L3_EN));
 128         }
 129
 130         ret |= adp5520_write(master, ADP5520_BL_CONTROL,
 131                         BL_CTRL_VAL(pdata->fade_led_law,
 132                                         pdata->en_ambl_sens));
 133
 134         ret |= adp5520_write(master, ADP5520_BL_FADE, FADE_VAL(pdata->fade_in,
 135                         pdata->fade_out));
 136
 137         ret |= adp5520_set_bits(master, ADP5520_MODE_STATUS,
 138                         ADP5520_BL_EN | ADP5520_DIM_EN);
 139
 140         return ret;
 141 }
 142
 143 static ssize_t adp5520_show(struct device *dev, char *buf, int reg)
 144 {
 145         struct adp5520_bl *data = dev_get_drvdata(dev);
 146         int error;
 147         uint8_t reg_val;
 148
 149         mutex_lock(&data->lock);
 150         error = adp5520_read(data->master, reg, &reg_val);
 151         mutex_unlock(&data->lock);
 152
 153         return sprintf(buf, "%u\n", reg_val);
 154 }
 155
 156 static ssize_t adp5520_store(struct device *dev, const char *buf,
 157                          size_t count, int reg)
 158 {
 159         struct adp5520_bl *data = dev_get_drvdata(dev);
 160         unsigned long val;
 161         int ret;
 162
 163         ret = strict_strtoul(buf, 10, &val);
 164         if (ret)
 165                 return ret;
 166
 167         mutex_lock(&data->lock);
 168         adp5520_write(data->master, reg, val);
 169         mutex_unlock(&data->lock);
 170
 171         return count;
 172 }
 173
 174 static ssize_t adp5520_bl_dark_max_show(struct device *dev,
 175                         struct device_attribute *attr, char *buf)
 176 {
 177         return adp5520_show(dev, buf, ADP5520_DARK_MAX);
 178 }
 179
 180 static ssize_t adp5520_bl_dark_max_store(struct device *dev,
 181                         struct device_attribute *attr,
 182                         const char *buf, size_t count)
 183 {
 184         return adp5520_store(dev, buf, count, ADP5520_DARK_MAX);
 185 }
 186 static DEVICE_ATTR(dark_max, 0664, adp5520_bl_dark_max_show,
 187                         adp5520_bl_dark_max_store);
 188
 189 static ssize_t adp5520_bl_office_max_show(struct device *dev,
 190                         struct device_attribute *attr, char *buf)
 191 {
 192         return adp5520_show(dev, buf, ADP5520_OFFICE_MAX);
 193 }
 194
 195 static ssize_t adp5520_bl_office_max_store(struct device *dev,
 196                         struct device_attribute *attr,
 197                         const char *buf, size_t count)
 198 {
 199         return adp5520_store(dev, buf, count, ADP5520_OFFICE_MAX);
 200 }
 201 static DEVICE_ATTR(office_max, 0664, adp5520_bl_office_max_show,
 202                         adp5520_bl_office_max_store);
 203
 204 static ssize_t adp5520_bl_daylight_max_show(struct device *dev,
 205                         struct device_attribute *attr, char *buf)
 206 {
 207         return adp5520_show(dev, buf, ADP5520_DAYLIGHT_MAX);
 208 }
 209
 210 static ssize_t adp5520_bl_daylight_max_store(struct device *dev,
 211                         struct device_attribute *attr,
 212                         const char *buf, size_t count)
 213 {
 214         struct adp5520_bl *data = dev_get_drvdata(dev);
 215         int ret;
 216
 217         ret = strict_strtoul(buf, 10, &data->cached_daylight_max);
 218         if (ret < 0)
 219                 return ret;
 220
 221         return adp5520_store(dev, buf, count, ADP5520_DAYLIGHT_MAX);
 222 }
 223 static DEVICE_ATTR(daylight_max, 0664, adp5520_bl_daylight_max_show,
 224                         adp5520_bl_daylight_max_store);
 225
 226 static ssize_t adp5520_bl_dark_dim_show(struct device *dev,
 227                         struct device_attribute *attr, char *buf)
 228 {
 229         return adp5520_show(dev, buf, ADP5520_DARK_DIM);
 230 }
 231
 232 static ssize_t adp5520_bl_dark_dim_store(struct device *dev,
 233                         struct device_attribute *attr,
 234                         const char *buf, size_t count)
 235 {
 236         return adp5520_store(dev, buf, count, ADP5520_DARK_DIM);
 237 }
 238 static DEVICE_ATTR(dark_dim, 0664, adp5520_bl_dark_dim_show,
 239                         adp5520_bl_dark_dim_store);
 240
 241 static ssize_t adp5520_bl_office_dim_show(struct device *dev,
 242                         struct device_attribute *attr, char *buf)
 243 {
 244         return adp5520_show(dev, buf, ADP5520_OFFICE_DIM);
 245 }
 246
 247 static ssize_t adp5520_bl_office_dim_store(struct device *dev,
 248                         struct device_attribute *attr,
 249                         const char *buf, size_t count)
 250 {
 251         return adp5520_store(dev, buf, count, ADP5520_OFFICE_DIM);
 252 }
 253 static DEVICE_ATTR(office_dim, 0664, adp5520_bl_office_dim_show,
 254                         adp5520_bl_office_dim_store);
 255
 256 static ssize_t adp5520_bl_daylight_dim_show(struct device *dev,
 257                         struct device_attribute *attr, char *buf)
 258 {
 259         return adp5520_show(dev, buf, ADP5520_DAYLIGHT_DIM);
 260 }
 261
 262 static ssize_t adp5520_bl_daylight_dim_store(struct device *dev,
 263                         struct device_attribute *attr,
 264                         const char *buf, size_t count)
 265 {
 266         return adp5520_store(dev, buf, count, ADP5520_DAYLIGHT_DIM);
 267 }
 268 static DEVICE_ATTR(daylight_dim, 0664, adp5520_bl_daylight_dim_show,
 269                         adp5520_bl_daylight_dim_store);
 270
 271 static struct attribute *adp5520_bl_attributes[] = {
 272         &dev_attr_dark_max.attr,
 273         &dev_attr_dark_dim.attr,
 274         &dev_attr_office_max.attr,
 275         &dev_attr_office_dim.attr,
 276         &dev_attr_daylight_max.attr,
 277         &dev_attr_daylight_dim.attr,
 278         NULL
 279 };
 280
 281 static const struct attribute_group adp5520_bl_attr_group = {
 282         .attrs = adp5520_bl_attributes,
 283 };
 284
 285 static int __devinit adp5520_bl_probe(struct platform_device *pdev)
 286 {
 287         struct backlight_properties props;
 288         struct backlight_device *bl;
 289         struct adp5520_bl *data;
 290         int ret = 0;
 291
 292         data = kzalloc(sizeof(*data), GFP_KERNEL);
 293         if (data == NULL)
 294                 return -ENOMEM;
 295
 296         data->master = pdev->dev.parent;
 297         data->pdata = pdev->dev.platform_data;
 298
 299         if (data->pdata  == NULL) {
 300                 dev_err(&pdev->dev, "missing platform data\n");
 301                 kfree(data);
 302                 return -ENODEV;
 303         }
 304
 305         data->id = pdev->id;
 306         data->current_brightness = 0;
 307
 308         mutex_init(&data->lock);
 309
 310         memset(&props, 0, sizeof(struct backlight_properties));
 311         props.type = BACKLIGHT_RAW;
 312         props.max_brightness = ADP5020_MAX_BRIGHTNESS;
 313         bl = backlight_device_register(pdev->name, data->master, data,
 314                                        &adp5520_bl_ops, &props);
 315         if (IS_ERR(bl)) {
 316                 dev_err(&pdev->dev, "failed to register backlight\n");
 317                 kfree(data);
 318                 return PTR_ERR(bl);
 319         }
 320
 321         bl->props.brightness = ADP5020_MAX_BRIGHTNESS;
 322         if (data->pdata->en_ambl_sens)
 323                 ret = sysfs_create_group(&bl->dev.kobj,
 324                         &adp5520_bl_attr_group);
 325
 326         if (ret) {
 327                 dev_err(&pdev->dev, "failed to register sysfs\n");
 328                 backlight_device_unregister(bl);
 329                 kfree(data);
 330         }
 331
 332         platform_set_drvdata(pdev, bl);
 333         ret |= adp5520_bl_setup(bl);
 334         backlight_update_status(bl);
 335
 336         return ret;
 337 }
 338
 339 static int __devexit adp5520_bl_remove(struct platform_device *pdev)
 340 {
 341         struct backlight_device *bl = platform_get_drvdata(pdev);
 342         struct adp5520_bl *data = bl_get_data(bl);
 343
 344         adp5520_clr_bits(data->master, ADP5520_MODE_STATUS, ADP5520_BL_EN);
 345
 346         if (data->pdata->en_ambl_sens)
 347                 sysfs_remove_group(&bl->dev.kobj,
 348                                 &adp5520_bl_attr_group);
 349
 350         backlight_device_unregister(bl);
 351         kfree(data);
 352
 353         return 0;
 354 }
 355
 356 #ifdef CONFIG_PM
 357 static int adp5520_bl_suspend(struct platform_device *pdev,
 358                                  pm_message_t state)
 359 {
 360         struct backlight_device *bl = platform_get_drvdata(pdev);
 361         return adp5520_bl_set(bl, 0);
 362 }
 363
 364 static int adp5520_bl_resume(struct platform_device *pdev)
 365 {
 366         struct backlight_device *bl = platform_get_drvdata(pdev);
 367
 368         backlight_update_status(bl);
 369         return 0;
 370 }
 371 #else
 372 #define adp5520_bl_suspend      NULL
 373 #define adp5520_bl_resume       NULL
 374 #endif
 375
 376 static struct platform_driver adp5520_bl_driver = {
 377         .driver         = {
 378                 .name   = "adp5520-backlight",
 379                 .owner  = THIS_MODULE,
 380         },
 381         .probe          = adp5520_bl_probe,
 382         .remove         = __devexit_p(adp5520_bl_remove),
 383         .suspend        = adp5520_bl_suspend,
 384         .resume         = adp5520_bl_resume,
 385 };
 386
 387 module_platform_driver(adp5520_bl_driver);
 388
 389 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
 390 MODULE_DESCRIPTION("ADP5520(01) Backlight Driver");
 391 MODULE_LICENSE("GPL");
 392 MODULE_ALIAS("platform:adp5520-backlight");