linux/drivers/leds/leds-max8997.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * leds-max8997.c - LED class driver for MAX8997 LEDs.
   4 *
   5 * Copyright (C) 2011 Samsung Electronics
   6 * Donggeun Kim <dg77.kim@samsung.com>
   7 */
   8
   9#include <linux/module.h>
  10#include <linux/err.h>
  11#include <linux/slab.h>
  12#include <linux/leds.h>
  13#include <linux/mfd/max8997.h>
  14#include <linux/mfd/max8997-private.h>
  15#include <linux/platform_device.h>
  16
  17#define MAX8997_LED_FLASH_SHIFT                 3
  18#define MAX8997_LED_FLASH_CUR_MASK              0xf8
  19#define MAX8997_LED_MOVIE_SHIFT                 4
  20#define MAX8997_LED_MOVIE_CUR_MASK              0xf0
  21
  22#define MAX8997_LED_FLASH_MAX_BRIGHTNESS        0x1f
  23#define MAX8997_LED_MOVIE_MAX_BRIGHTNESS        0xf
  24#define MAX8997_LED_NONE_MAX_BRIGHTNESS         0
  25
  26#define MAX8997_LED0_FLASH_MASK                 0x1
  27#define MAX8997_LED0_FLASH_PIN_MASK             0x5
  28#define MAX8997_LED0_MOVIE_MASK                 0x8
  29#define MAX8997_LED0_MOVIE_PIN_MASK             0x28
  30
  31#define MAX8997_LED1_FLASH_MASK                 0x2
  32#define MAX8997_LED1_FLASH_PIN_MASK             0x6
  33#define MAX8997_LED1_MOVIE_MASK                 0x10
  34#define MAX8997_LED1_MOVIE_PIN_MASK             0x30
  35
  36#define MAX8997_LED_BOOST_ENABLE_MASK           (1 << 6)
  37
  38struct max8997_led {
  39        struct max8997_dev *iodev;
  40        struct led_classdev cdev;
  41        bool enabled;
  42        int id;
  43        enum max8997_led_mode led_mode;
  44        struct mutex mutex;
  45};
  46
  47static void max8997_led_set_mode(struct max8997_led *led,
  48                        enum max8997_led_mode mode)
  49{
  50        int ret;
  51        struct i2c_client *client = led->iodev->i2c;
  52        u8 mask = 0, val;
  53
  54        switch (mode) {
  55        case MAX8997_FLASH_MODE:
  56                mask = MAX8997_LED1_FLASH_MASK | MAX8997_LED0_FLASH_MASK;
  57                val = led->id ?
  58                      MAX8997_LED1_FLASH_MASK : MAX8997_LED0_FLASH_MASK;
  59                led->cdev.max_brightness = MAX8997_LED_FLASH_MAX_BRIGHTNESS;
  60                break;
  61        case MAX8997_MOVIE_MODE:
  62                mask = MAX8997_LED1_MOVIE_MASK | MAX8997_LED0_MOVIE_MASK;
  63                val = led->id ?
  64                      MAX8997_LED1_MOVIE_MASK : MAX8997_LED0_MOVIE_MASK;
  65                led->cdev.max_brightness = MAX8997_LED_MOVIE_MAX_BRIGHTNESS;
  66                break;
  67        case MAX8997_FLASH_PIN_CONTROL_MODE:
  68                mask = MAX8997_LED1_FLASH_PIN_MASK |
  69                       MAX8997_LED0_FLASH_PIN_MASK;
  70                val = led->id ?
  71                      MAX8997_LED1_FLASH_PIN_MASK : MAX8997_LED0_FLASH_PIN_MASK;
  72                led->cdev.max_brightness = MAX8997_LED_FLASH_MAX_BRIGHTNESS;
  73                break;
  74        case MAX8997_MOVIE_PIN_CONTROL_MODE:
  75                mask = MAX8997_LED1_MOVIE_PIN_MASK |
  76                       MAX8997_LED0_MOVIE_PIN_MASK;
  77                val = led->id ?
  78                      MAX8997_LED1_MOVIE_PIN_MASK : MAX8997_LED0_MOVIE_PIN_MASK;
  79                led->cdev.max_brightness = MAX8997_LED_MOVIE_MAX_BRIGHTNESS;
  80                break;
  81        default:
  82                led->cdev.max_brightness = MAX8997_LED_NONE_MAX_BRIGHTNESS;
  83                break;
  84        }
  85
  86        if (mask) {
  87                ret = max8997_update_reg(client, MAX8997_REG_LEN_CNTL, val,
  88                                         mask);
  89                if (ret)
  90                        dev_err(led->iodev->dev,
  91                                "failed to update register(%d)\n", ret);
  92        }
  93
  94        led->led_mode = mode;
  95}
  96
  97static void max8997_led_enable(struct max8997_led *led, bool enable)
  98{
  99        int ret;
 100        struct i2c_client *client = led->iodev->i2c;
 101        u8 val = 0, mask = MAX8997_LED_BOOST_ENABLE_MASK;
 102
 103        if (led->enabled == enable)
 104                return;
 105
 106        val = enable ? MAX8997_LED_BOOST_ENABLE_MASK : 0;
 107
 108        ret = max8997_update_reg(client, MAX8997_REG_BOOST_CNTL, val, mask);
 109        if (ret)
 110                dev_err(led->iodev->dev,
 111                        "failed to update register(%d)\n", ret);
 112
 113        led->enabled = enable;
 114}
 115
 116static void max8997_led_set_current(struct max8997_led *led,
 117                                enum led_brightness value)
 118{
 119        int ret;
 120        struct i2c_client *client = led->iodev->i2c;
 121        u8 val = 0, mask = 0, reg = 0;
 122
 123        switch (led->led_mode) {
 124        case MAX8997_FLASH_MODE:
 125        case MAX8997_FLASH_PIN_CONTROL_MODE:
 126                val = value << MAX8997_LED_FLASH_SHIFT;
 127                mask = MAX8997_LED_FLASH_CUR_MASK;
 128                reg = led->id ? MAX8997_REG_FLASH2_CUR : MAX8997_REG_FLASH1_CUR;
 129                break;
 130        case MAX8997_MOVIE_MODE:
 131        case MAX8997_MOVIE_PIN_CONTROL_MODE:
 132                val = value << MAX8997_LED_MOVIE_SHIFT;
 133                mask = MAX8997_LED_MOVIE_CUR_MASK;
 134                reg = MAX8997_REG_MOVIE_CUR;
 135                break;
 136        default:
 137                break;
 138        }
 139
 140        if (mask) {
 141                ret = max8997_update_reg(client, reg, val, mask);
 142                if (ret)
 143                        dev_err(led->iodev->dev,
 144                                "failed to update register(%d)\n", ret);
 145        }
 146}
 147
 148static void max8997_led_brightness_set(struct led_classdev *led_cdev,
 149                                enum led_brightness value)
 150{
 151        struct max8997_led *led =
 152                        container_of(led_cdev, struct max8997_led, cdev);
 153
 154        if (value) {
 155                max8997_led_set_current(led, value);
 156                max8997_led_enable(led, true);
 157        } else {
 158                max8997_led_set_current(led, value);
 159                max8997_led_enable(led, false);
 160        }
 161}
 162
 163static ssize_t mode_show(struct device *dev,
 164                         struct device_attribute *attr, char *buf)
 165{
 166        struct led_classdev *led_cdev = dev_get_drvdata(dev);
 167        struct max8997_led *led =
 168                        container_of(led_cdev, struct max8997_led, cdev);
 169        ssize_t ret = 0;
 170
 171        mutex_lock(&led->mutex);
 172
 173        switch (led->led_mode) {
 174        case MAX8997_FLASH_MODE:
 175                ret += sprintf(buf, "FLASH\n");
 176                break;
 177        case MAX8997_MOVIE_MODE:
 178                ret += sprintf(buf, "MOVIE\n");
 179                break;
 180        case MAX8997_FLASH_PIN_CONTROL_MODE:
 181                ret += sprintf(buf, "FLASH_PIN_CONTROL\n");
 182                break;
 183        case MAX8997_MOVIE_PIN_CONTROL_MODE:
 184                ret += sprintf(buf, "MOVIE_PIN_CONTROL\n");
 185                break;
 186        default:
 187                ret += sprintf(buf, "NONE\n");
 188                break;
 189        }
 190
 191        mutex_unlock(&led->mutex);
 192
 193        return ret;
 194}
 195
 196static ssize_t mode_store(struct device *dev,
 197                          struct device_attribute *attr,
 198                          const char *buf, size_t size)
 199{
 200        struct led_classdev *led_cdev = dev_get_drvdata(dev);
 201        struct max8997_led *led =
 202                        container_of(led_cdev, struct max8997_led, cdev);
 203        enum max8997_led_mode mode;
 204
 205        mutex_lock(&led->mutex);
 206
 207        if (!strncmp(buf, "FLASH_PIN_CONTROL", 17))
 208                mode = MAX8997_FLASH_PIN_CONTROL_MODE;
 209        else if (!strncmp(buf, "MOVIE_PIN_CONTROL", 17))
 210                mode = MAX8997_MOVIE_PIN_CONTROL_MODE;
 211        else if (!strncmp(buf, "FLASH", 5))
 212                mode = MAX8997_FLASH_MODE;
 213        else if (!strncmp(buf, "MOVIE", 5))
 214                mode = MAX8997_MOVIE_MODE;
 215        else
 216                mode = MAX8997_NONE;
 217
 218        max8997_led_set_mode(led, mode);
 219
 220        mutex_unlock(&led->mutex);
 221
 222        return size;
 223}
 224
 225static DEVICE_ATTR_RW(mode);
 226
 227static struct attribute *max8997_attrs[] = {
 228        &dev_attr_mode.attr,
 229        NULL
 230};
 231ATTRIBUTE_GROUPS(max8997);
 232
 233static int max8997_led_probe(struct platform_device *pdev)
 234{
 235        struct max8997_dev *iodev = dev_get_drvdata(pdev->dev.parent);
 236        struct max8997_platform_data *pdata = dev_get_platdata(iodev->dev);
 237        struct max8997_led *led;
 238        char name[20];
 239        int ret = 0;
 240
 241        if (pdata == NULL) {
 242                dev_err(&pdev->dev, "no platform data\n");
 243                return -ENODEV;
 244        }
 245
 246        led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);
 247        if (led == NULL)
 248                return -ENOMEM;
 249
 250        led->id = pdev->id;
 251        snprintf(name, sizeof(name), "max8997-led%d", pdev->id);
 252
 253        led->cdev.name = name;
 254        led->cdev.brightness_set = max8997_led_brightness_set;
 255        led->cdev.flags |= LED_CORE_SUSPENDRESUME;
 256        led->cdev.brightness = 0;
 257        led->cdev.groups = max8997_groups;
 258        led->iodev = iodev;
 259
 260        /* initialize mode and brightness according to platform_data */
 261        if (pdata->led_pdata) {
 262                u8 mode = 0, brightness = 0;
 263
 264                mode = pdata->led_pdata->mode[led->id];
 265                brightness = pdata->led_pdata->brightness[led->id];
 266
 267                max8997_led_set_mode(led, mode);
 268
 269                if (brightness > led->cdev.max_brightness)
 270                        brightness = led->cdev.max_brightness;
 271                max8997_led_set_current(led, brightness);
 272                led->cdev.brightness = brightness;
 273        } else {
 274                max8997_led_set_mode(led, MAX8997_NONE);
 275                max8997_led_set_current(led, 0);
 276        }
 277
 278        mutex_init(&led->mutex);
 279
 280        ret = devm_led_classdev_register(&pdev->dev, &led->cdev);
 281        if (ret < 0)
 282                return ret;
 283
 284        return 0;
 285}
 286
 287static struct platform_driver max8997_led_driver = {
 288        .driver = {
 289                .name  = "max8997-led",
 290        },
 291        .probe  = max8997_led_probe,
 292};
 293
 294module_platform_driver(max8997_led_driver);
 295
 296MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
 297MODULE_DESCRIPTION("MAX8997 LED driver");
 298MODULE_LICENSE("GPL");
 299MODULE_ALIAS("platform:max8997-led");
 300