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/leds.h>
  17 #include <linux/mfd/max8997.h>
  18 #include <linux/mfd/max8997-private.h>
  19 #include <linux/platform_device.h>
  20
  21 #define MAX8997_LED_FLASH_SHIFT                 3
  22 #define MAX8997_LED_FLASH_CUR_MASK              0xf8
  23 #define MAX8997_LED_MOVIE_SHIFT                 4
  24 #define MAX8997_LED_MOVIE_CUR_MASK              0xf0
  25
  26 #define MAX8997_LED_FLASH_MAX_BRIGHTNESS        0x1f
  27 #define MAX8997_LED_MOVIE_MAX_BRIGHTNESS        0xf
  28 #define MAX8997_LED_NONE_MAX_BRIGHTNESS         0
  29
  30 #define MAX8997_LED0_FLASH_MASK                 0x1
  31 #define MAX8997_LED0_FLASH_PIN_MASK             0x5
  32 #define MAX8997_LED0_MOVIE_MASK                 0x8
  33 #define MAX8997_LED0_MOVIE_PIN_MASK             0x28
  34
  35 #define MAX8997_LED1_FLASH_MASK                 0x2
  36 #define MAX8997_LED1_FLASH_PIN_MASK             0x6
  37 #define MAX8997_LED1_MOVIE_MASK                 0x10
  38 #define MAX8997_LED1_MOVIE_PIN_MASK             0x30
  39
  40 #define MAX8997_LED_BOOST_ENABLE_MASK           (1 << 6)
  41
  42 struct max8997_led {
  43         struct max8997_dev *iodev;
  44         struct led_classdev cdev;
  45         bool enabled;
  46         int id;
  47         enum max8997_led_mode led_mode;
  48         struct mutex mutex;
  49 };
  50
  51 static void max8997_led_set_mode(struct max8997_led *led,
  52                         enum max8997_led_mode mode)
  53 {
  54         int ret;
  55         struct i2c_client *client = led->iodev->i2c;
  56         u8 mask = 0, val;
  57
  58         switch (mode) {
  59         case MAX8997_FLASH_MODE:
  60                 mask = MAX8997_LED1_FLASH_MASK | MAX8997_LED0_FLASH_MASK;
  61                 val = led->id ?
  62                       MAX8997_LED1_FLASH_MASK : MAX8997_LED0_FLASH_MASK;
  63                 led->cdev.max_brightness = MAX8997_LED_FLASH_MAX_BRIGHTNESS;
  64                 break;
  65         case MAX8997_MOVIE_MODE:
  66                 mask = MAX8997_LED1_MOVIE_MASK | MAX8997_LED0_MOVIE_MASK;
  67                 val = led->id ?
  68                       MAX8997_LED1_MOVIE_MASK : MAX8997_LED0_MOVIE_MASK;
  69                 led->cdev.max_brightness = MAX8997_LED_MOVIE_MAX_BRIGHTNESS;
  70                 break;
  71         case MAX8997_FLASH_PIN_CONTROL_MODE:
  72                 mask = MAX8997_LED1_FLASH_PIN_MASK |
  73                        MAX8997_LED0_FLASH_PIN_MASK;
  74                 val = led->id ?
  75                       MAX8997_LED1_FLASH_PIN_MASK : MAX8997_LED0_FLASH_PIN_MASK;
  76                 led->cdev.max_brightness = MAX8997_LED_FLASH_MAX_BRIGHTNESS;
  77                 break;
  78         case MAX8997_MOVIE_PIN_CONTROL_MODE:
  79                 mask = MAX8997_LED1_MOVIE_PIN_MASK |
  80                        MAX8997_LED0_MOVIE_PIN_MASK;
  81                 val = led->id ?
  82                       MAX8997_LED1_MOVIE_PIN_MASK : MAX8997_LED0_MOVIE_PIN_MASK;
  83                 led->cdev.max_brightness = MAX8997_LED_MOVIE_MAX_BRIGHTNESS;
  84                 break;
  85         default:
  86                 led->cdev.max_brightness = MAX8997_LED_NONE_MAX_BRIGHTNESS;
  87                 break;
  88         }
  89
  90         if (mask) {
  91                 ret = max8997_update_reg(client, MAX8997_REG_LEN_CNTL, val,
  92                                          mask);
  93                 if (ret)
  94                         dev_err(led->iodev->dev,
  95                                 "failed to update register(%d)\n", ret);
  96         }
  97
  98         led->led_mode = mode;
  99 }
 100
 101 static void max8997_led_enable(struct max8997_led *led, bool enable)
 102 {
 103         int ret;
 104         struct i2c_client *client = led->iodev->i2c;
 105         u8 val = 0, mask = MAX8997_LED_BOOST_ENABLE_MASK;
 106
 107         if (led->enabled == enable)
 108                 return;
 109
 110         val = enable ? MAX8997_LED_BOOST_ENABLE_MASK : 0;
 111
 112         ret = max8997_update_reg(client, MAX8997_REG_BOOST_CNTL, val, mask);
 113         if (ret)
 114                 dev_err(led->iodev->dev,
 115                         "failed to update register(%d)\n", ret);
 116
 117         led->enabled = enable;
 118 }
 119
 120 static void max8997_led_set_current(struct max8997_led *led,
 121                                 enum led_brightness value)
 122 {
 123         int ret;
 124         struct i2c_client *client = led->iodev->i2c;
 125         u8 val = 0, mask = 0, reg = 0;
 126
 127         switch (led->led_mode) {
 128         case MAX8997_FLASH_MODE:
 129         case MAX8997_FLASH_PIN_CONTROL_MODE:
 130                 val = value << MAX8997_LED_FLASH_SHIFT;
 131                 mask = MAX8997_LED_FLASH_CUR_MASK;
 132                 reg = led->id ? MAX8997_REG_FLASH2_CUR : MAX8997_REG_FLASH1_CUR;
 133                 break;
 134         case MAX8997_MOVIE_MODE:
 135         case MAX8997_MOVIE_PIN_CONTROL_MODE:
 136                 val = value << MAX8997_LED_MOVIE_SHIFT;
 137                 mask = MAX8997_LED_MOVIE_CUR_MASK;
 138                 reg = MAX8997_REG_MOVIE_CUR;
 139                 break;
 140         default:
 141                 break;
 142         }
 143
 144         if (mask) {
 145                 ret = max8997_update_reg(client, reg, val, mask);
 146                 if (ret)
 147                         dev_err(led->iodev->dev,
 148                                 "failed to update register(%d)\n", ret);
 149         }
 150 }
 151
 152 static void max8997_led_brightness_set(struct led_classdev *led_cdev,
 153                                 enum led_brightness value)
 154 {
 155         struct max8997_led *led =
 156                         container_of(led_cdev, struct max8997_led, cdev);
 157
 158         if (value) {
 159                 max8997_led_set_current(led, value);
 160                 max8997_led_enable(led, true);
 161         } else {
 162                 max8997_led_set_current(led, value);
 163                 max8997_led_enable(led, false);
 164         }
 165 }
 166
 167 static ssize_t max8997_led_show_mode(struct device *dev,
 168                                 struct device_attribute *attr, char *buf)
 169 {
 170         struct led_classdev *led_cdev = dev_get_drvdata(dev);
 171         struct max8997_led *led =
 172                         container_of(led_cdev, struct max8997_led, cdev);
 173         ssize_t ret = 0;
 174
 175         mutex_lock(&led->mutex);
 176
 177         switch (led->led_mode) {
 178         case MAX8997_FLASH_MODE:
 179                 ret += sprintf(buf, "FLASH\n");
 180                 break;
 181         case MAX8997_MOVIE_MODE:
 182                 ret += sprintf(buf, "MOVIE\n");
 183                 break;
 184         case MAX8997_FLASH_PIN_CONTROL_MODE:
 185                 ret += sprintf(buf, "FLASH_PIN_CONTROL\n");
 186                 break;
 187         case MAX8997_MOVIE_PIN_CONTROL_MODE:
 188                 ret += sprintf(buf, "MOVIE_PIN_CONTROL\n");
 189                 break;
 190         default:
 191                 ret += sprintf(buf, "NONE\n");
 192                 break;
 193         }
 194
 195         mutex_unlock(&led->mutex);
 196
 197         return ret;
 198 }
 199
 200 static ssize_t max8997_led_store_mode(struct device *dev,
 201                                 struct device_attribute *attr,
 202                                 const char *buf, size_t size)
 203 {
 204         struct led_classdev *led_cdev = dev_get_drvdata(dev);
 205         struct max8997_led *led =
 206                         container_of(led_cdev, struct max8997_led, cdev);
 207         enum max8997_led_mode mode;
 208
 209         mutex_lock(&led->mutex);
 210
 211         if (!strncmp(buf, "FLASH_PIN_CONTROL", 17))
 212                 mode = MAX8997_FLASH_PIN_CONTROL_MODE;
 213         else if (!strncmp(buf, "MOVIE_PIN_CONTROL", 17))
 214                 mode = MAX8997_MOVIE_PIN_CONTROL_MODE;
 215         else if (!strncmp(buf, "FLASH", 5))
 216                 mode = MAX8997_FLASH_MODE;
 217         else if (!strncmp(buf, "MOVIE", 5))
 218                 mode = MAX8997_MOVIE_MODE;
 219         else
 220                 mode = MAX8997_NONE;
 221
 222         max8997_led_set_mode(led, mode);
 223
 224         mutex_unlock(&led->mutex);
 225
 226         return size;
 227 }
 228
 229 static DEVICE_ATTR(mode, 0644, max8997_led_show_mode, max8997_led_store_mode);
 230
 231 static struct attribute *max8997_attrs[] = {
 232         &dev_attr_mode.attr,
 233         NULL
 234 };
 235 ATTRIBUTE_GROUPS(max8997);
 236
 237 static int max8997_led_probe(struct platform_device *pdev)
 238 {
 239         struct max8997_dev *iodev = dev_get_drvdata(pdev->dev.parent);
 240         struct max8997_platform_data *pdata = dev_get_platdata(iodev->dev);
 241         struct max8997_led *led;
 242         char name[20];
 243         int ret = 0;
 244
 245         if (pdata == NULL) {
 246                 dev_err(&pdev->dev, "no platform data\n");
 247                 return -ENODEV;
 248         }
 249
 250         led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);
 251         if (led == NULL)
 252                 return -ENOMEM;
 253
 254         led->id = pdev->id;
 255         snprintf(name, sizeof(name), "max8997-led%d", pdev->id);
 256
 257         led->cdev.name = name;
 258         led->cdev.brightness_set = max8997_led_brightness_set;
 259         led->cdev.flags |= LED_CORE_SUSPENDRESUME;
 260         led->cdev.brightness = 0;
 261         led->cdev.groups = max8997_groups;
 262         led->iodev = iodev;
 263
 264         /* initialize mode and brightness according to platform_data */
 265         if (pdata->led_pdata) {
 266                 u8 mode = 0, brightness = 0;
 267
 268                 mode = pdata->led_pdata->mode[led->id];
 269                 brightness = pdata->led_pdata->brightness[led->id];
 270
 271                 max8997_led_set_mode(led, mode);
 272
 273                 if (brightness > led->cdev.max_brightness)
 274                         brightness = led->cdev.max_brightness;
 275                 max8997_led_set_current(led, brightness);
 276                 led->cdev.brightness = brightness;
 277         } else {
 278                 max8997_led_set_mode(led, MAX8997_NONE);
 279                 max8997_led_set_current(led, 0);
 280         }
 281
 282         mutex_init(&led->mutex);
 283
 284         ret = devm_led_classdev_register(&pdev->dev, &led->cdev);
 285         if (ret < 0)
 286                 return ret;
 287
 288         return 0;
 289 }
 290
 291 static struct platform_driver max8997_led_driver = {
 292         .driver = {
 293                 .name  = "max8997-led",
 294         },
 295         .probe  = max8997_led_probe,
 296 };
 297
 298 module_platform_driver(max8997_led_driver);
 299
 300 MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
 301 MODULE_DESCRIPTION("MAX8997 LED driver");
 302 MODULE_LICENSE("GPL");
 303 MODULE_ALIAS("platform:max8997-led");