drivers/leds/leds-max8997.c

   1 /*
   2  * leds-max8997.c - LED class driver for MAX8997 LEDs.
   3  *
   4  * Copyright (C) 2011 Samsung Electronics
   5  * Donggeun Kim <dg77.kim@samsung.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  *
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/err.h>
  15 #include <linux/slab.h>
  16 #include <linux/workqueue.h>
  17 #include <linux/leds.h>
  18 #include <linux/mfd/max8997.h>
  19 #include <linux/mfd/max8997-private.h>
  20 #include <linux/platform_device.h>
  21
  22 #define MAX8997_LED_FLASH_SHIFT                 3
  23 #define MAX8997_LED_FLASH_CUR_MASK              0xf8
  24 #define MAX8997_LED_MOVIE_SHIFT                 4
  25 #define MAX8997_LED_MOVIE_CUR_MASK              0xf0
  26
  27 #define MAX8997_LED_FLASH_MAX_BRIGHTNESS        0x1f
  28 #define MAX8997_LED_MOVIE_MAX_BRIGHTNESS        0xf
  29 #define MAX8997_LED_NONE_MAX_BRIGHTNESS         0
  30
  31 #define MAX8997_LED0_FLASH_MASK                 0x1
  32 #define MAX8997_LED0_FLASH_PIN_MASK             0x5
  33 #define MAX8997_LED0_MOVIE_MASK                 0x8
  34 #define MAX8997_LED0_MOVIE_PIN_MASK             0x28
  35
  36 #define MAX8997_LED1_FLASH_MASK                 0x2
  37 #define MAX8997_LED1_FLASH_PIN_MASK             0x6
  38 #define MAX8997_LED1_MOVIE_MASK                 0x10
  39 #define MAX8997_LED1_MOVIE_PIN_MASK             0x30
  40
  41 #define MAX8997_LED_BOOST_ENABLE_MASK           (1 << 6)
  42
  43 struct max8997_led {
  44         struct max8997_dev *iodev;
  45         struct led_classdev cdev;
  46         bool enabled;
  47         int id;
  48         enum max8997_led_mode led_mode;
  49         struct mutex mutex;
  50 };
  51
  52 static void max8997_led_set_mode(struct max8997_led *led,
  53                         enum max8997_led_mode mode)
  54 {
  55         int ret;
  56         struct i2c_client *client = led->iodev->i2c;
  57         u8 mask = 0, val;
  58
  59         switch (mode) {
  60         case MAX8997_FLASH_MODE:
  61                 mask = MAX8997_LED1_FLASH_MASK | MAX8997_LED0_FLASH_MASK;
  62                 val = led->id ?
  63                       MAX8997_LED1_FLASH_MASK : MAX8997_LED0_FLASH_MASK;
  64                 led->cdev.max_brightness = MAX8997_LED_FLASH_MAX_BRIGHTNESS;
  65                 break;
  66         case MAX8997_MOVIE_MODE:
  67                 mask = MAX8997_LED1_MOVIE_MASK | MAX8997_LED0_MOVIE_MASK;
  68                 val = led->id ?
  69                       MAX8997_LED1_MOVIE_MASK : MAX8997_LED0_MOVIE_MASK;
  70                 led->cdev.max_brightness = MAX8997_LED_MOVIE_MAX_BRIGHTNESS;
  71                 break;
  72         case MAX8997_FLASH_PIN_CONTROL_MODE:
  73                 mask = MAX8997_LED1_FLASH_PIN_MASK |
  74                        MAX8997_LED0_FLASH_PIN_MASK;
  75                 val = led->id ?
  76                       MAX8997_LED1_FLASH_PIN_MASK : MAX8997_LED0_FLASH_PIN_MASK;
  77                 led->cdev.max_brightness = MAX8997_LED_FLASH_MAX_BRIGHTNESS;
  78                 break;
  79         case MAX8997_MOVIE_PIN_CONTROL_MODE:
  80                 mask = MAX8997_LED1_MOVIE_PIN_MASK |
  81                        MAX8997_LED0_MOVIE_PIN_MASK;
  82                 val = led->id ?
  83                       MAX8997_LED1_MOVIE_PIN_MASK : MAX8997_LED0_MOVIE_PIN_MASK;
  84                 led->cdev.max_brightness = MAX8997_LED_MOVIE_MAX_BRIGHTNESS;
  85                 break;
  86         default:
  87                 led->cdev.max_brightness = MAX8997_LED_NONE_MAX_BRIGHTNESS;
  88                 break;
  89         }
  90
  91         if (mask) {
  92                 ret = max8997_update_reg(client, MAX8997_REG_LEN_CNTL, val,
  93                                          mask);
  94                 if (ret)
  95                         dev_err(led->iodev->dev,
  96                                 "failed to update register(%d)\n", ret);
  97         }
  98
  99         led->led_mode = mode;
 100 }
 101
 102 static void max8997_led_enable(struct max8997_led *led, bool enable)
 103 {
 104         int ret;
 105         struct i2c_client *client = led->iodev->i2c;
 106         u8 val = 0, mask = MAX8997_LED_BOOST_ENABLE_MASK;
 107
 108         if (led->enabled == enable)
 109                 return;
 110
 111         val = enable ? MAX8997_LED_BOOST_ENABLE_MASK : 0;
 112
 113         ret = max8997_update_reg(client, MAX8997_REG_BOOST_CNTL, val, mask);
 114         if (ret)
 115                 dev_err(led->iodev->dev,
 116                         "failed to update register(%d)\n", ret);
 117
 118         led->enabled = enable;
 119 }
 120
 121 static void max8997_led_set_current(struct max8997_led *led,
 122                                 enum led_brightness value)
 123 {
 124         int ret;
 125         struct i2c_client *client = led->iodev->i2c;
 126         u8 val = 0, mask = 0, reg = 0;
 127
 128         switch (led->led_mode) {
 129         case MAX8997_FLASH_MODE:
 130         case MAX8997_FLASH_PIN_CONTROL_MODE:
 131                 val = value << MAX8997_LED_FLASH_SHIFT;
 132                 mask = MAX8997_LED_FLASH_CUR_MASK;
 133                 reg = led->id ? MAX8997_REG_FLASH2_CUR : MAX8997_REG_FLASH1_CUR;
 134                 break;
 135         case MAX8997_MOVIE_MODE:
 136         case MAX8997_MOVIE_PIN_CONTROL_MODE:
 137                 val = value << MAX8997_LED_MOVIE_SHIFT;
 138                 mask = MAX8997_LED_MOVIE_CUR_MASK;
 139                 reg = MAX8997_REG_MOVIE_CUR;
 140                 break;
 141         default:
 142                 break;
 143         }
 144
 145         if (mask) {
 146                 ret = max8997_update_reg(client, reg, val, mask);
 147                 if (ret)
 148                         dev_err(led->iodev->dev,
 149                                 "failed to update register(%d)\n", ret);
 150         }
 151 }
 152
 153 static void max8997_led_brightness_set(struct led_classdev *led_cdev,
 154                                 enum led_brightness value)
 155 {
 156         struct max8997_led *led =
 157                         container_of(led_cdev, struct max8997_led, cdev);
 158
 159         if (value) {
 160                 max8997_led_set_current(led, value);
 161                 max8997_led_enable(led, true);
 162         } else {
 163                 max8997_led_set_current(led, value);
 164                 max8997_led_enable(led, false);
 165         }
 166 }
 167
 168 static ssize_t max8997_led_show_mode(struct device *dev,
 169                                 struct device_attribute *attr, char *buf)
 170 {
 171         struct led_classdev *led_cdev = dev_get_drvdata(dev);
 172         struct max8997_led *led =
 173                         container_of(led_cdev, struct max8997_led, cdev);
 174         ssize_t ret = 0;
 175
 176         mutex_lock(&led->mutex);
 177
 178         switch (led->led_mode) {
 179         case MAX8997_FLASH_MODE:
 180                 ret += sprintf(buf, "FLASH\n");
 181                 break;
 182         case MAX8997_MOVIE_MODE:
 183                 ret += sprintf(buf, "MOVIE\n");
 184                 break;
 185         case MAX8997_FLASH_PIN_CONTROL_MODE:
 186                 ret += sprintf(buf, "FLASH_PIN_CONTROL\n");
 187                 break;
 188         case MAX8997_MOVIE_PIN_CONTROL_MODE:
 189                 ret += sprintf(buf, "MOVIE_PIN_CONTROL\n");
 190                 break;
 191         default:
 192                 ret += sprintf(buf, "NONE\n");
 193                 break;
 194         }
 195
 196         mutex_unlock(&led->mutex);
 197
 198         return ret;
 199 }
 200
 201 static ssize_t max8997_led_store_mode(struct device *dev,
 202                                 struct device_attribute *attr,
 203                                 const char *buf, size_t size)
 204 {
 205         struct led_classdev *led_cdev = dev_get_drvdata(dev);
 206         struct max8997_led *led =
 207                         container_of(led_cdev, struct max8997_led, cdev);
 208         enum max8997_led_mode mode;
 209
 210         mutex_lock(&led->mutex);
 211
 212         if (!strncmp(buf, "FLASH_PIN_CONTROL", 17))
 213                 mode = MAX8997_FLASH_PIN_CONTROL_MODE;
 214         else if (!strncmp(buf, "MOVIE_PIN_CONTROL", 17))
 215                 mode = MAX8997_MOVIE_PIN_CONTROL_MODE;
 216         else if (!strncmp(buf, "FLASH", 5))
 217                 mode = MAX8997_FLASH_MODE;
 218         else if (!strncmp(buf, "MOVIE", 5))
 219                 mode = MAX8997_MOVIE_MODE;
 220         else
 221                 mode = MAX8997_NONE;
 222
 223         max8997_led_set_mode(led, mode);
 224
 225         mutex_unlock(&led->mutex);
 226
 227         return size;
 228 }
 229
 230 static DEVICE_ATTR(mode, 0644, max8997_led_show_mode, max8997_led_store_mode);
 231
 232 static int max8997_led_probe(struct platform_device *pdev)
 233 {
 234         struct max8997_dev *iodev = dev_get_drvdata(pdev->dev.parent);
 235         struct max8997_platform_data *pdata = dev_get_platdata(iodev->dev);
 236         struct max8997_led *led;
 237         char name[20];
 238         int ret = 0;
 239
 240         if (pdata == NULL) {
 241                 dev_err(&pdev->dev, "no platform data\n");
 242                 return -ENODEV;
 243         }
 244
 245         led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);
 246         if (led == NULL)
 247                 return -ENOMEM;
 248
 249         led->id = pdev->id;
 250         snprintf(name, sizeof(name), "max8997-led%d", pdev->id);
 251
 252         led->cdev.name = name;
 253         led->cdev.brightness_set = max8997_led_brightness_set;
 254         led->cdev.flags |= LED_CORE_SUSPENDRESUME;
 255         led->cdev.brightness = 0;
 256         led->iodev = iodev;
 257
 258         /* initialize mode and brightness according to platform_data */
 259         if (pdata->led_pdata) {
 260                 u8 mode = 0, brightness = 0;
 261
 262                 mode = pdata->led_pdata->mode[led->id];
 263                 brightness = pdata->led_pdata->brightness[led->id];
 264
 265                 max8997_led_set_mode(led, pdata->led_pdata->mode[led->id]);
 266
 267                 if (brightness > led->cdev.max_brightness)
 268                         brightness = led->cdev.max_brightness;
 269                 max8997_led_set_current(led, brightness);
 270                 led->cdev.brightness = brightness;
 271         } else {
 272                 max8997_led_set_mode(led, MAX8997_NONE);
 273                 max8997_led_set_current(led, 0);
 274         }
 275
 276         mutex_init(&led->mutex);
 277
 278         platform_set_drvdata(pdev, led);
 279
 280         ret = led_classdev_register(&pdev->dev, &led->cdev);
 281         if (ret < 0)
 282                 return ret;
 283
 284         ret = device_create_file(led->cdev.dev, &dev_attr_mode);
 285         if (ret != 0) {
 286                 dev_err(&pdev->dev,
 287                         "failed to create file: %d\n", ret);
 288                 led_classdev_unregister(&led->cdev);
 289                 return ret;
 290         }
 291
 292         return 0;
 293 }
 294
 295 static int max8997_led_remove(struct platform_device *pdev)
 296 {
 297         struct max8997_led *led = platform_get_drvdata(pdev);
 298
 299         device_remove_file(led->cdev.dev, &dev_attr_mode);
 300         led_classdev_unregister(&led->cdev);
 301
 302         return 0;
 303 }
 304
 305 static struct platform_driver max8997_led_driver = {
 306         .driver = {
 307                 .name  = "max8997-led",
 308                 .owner = THIS_MODULE,
 309         },
 310         .probe  = max8997_led_probe,
 311         .remove = max8997_led_remove,
 312 };
 313
 314 module_platform_driver(max8997_led_driver);
 315
 316 MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
 317 MODULE_DESCRIPTION("MAX8997 LED driver");
 318 MODULE_LICENSE("GPL");
 319 MODULE_ALIAS("platform:max8997-led");