drivers/video/backlight/lm3639_bl.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3 * Simple driver for Texas Instruments LM3639 Backlight + Flash LED driver chip
   4 * Copyright (C) 2012 Texas Instruments
   5 */
   6 #include <linux/module.h>
   7 #include <linux/slab.h>
   8 #include <linux/i2c.h>
   9 #include <linux/leds.h>
  10 #include <linux/backlight.h>
  11 #include <linux/err.h>
  12 #include <linux/delay.h>
  13 #include <linux/uaccess.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/regmap.h>
  16 #include <linux/platform_data/lm3639_bl.h>
  17
  18 #define REG_DEV_ID      0x00
  19 #define REG_CHECKSUM    0x01
  20 #define REG_BL_CONF_1   0x02
  21 #define REG_BL_CONF_2   0x03
  22 #define REG_BL_CONF_3   0x04
  23 #define REG_BL_CONF_4   0x05
  24 #define REG_FL_CONF_1   0x06
  25 #define REG_FL_CONF_2   0x07
  26 #define REG_FL_CONF_3   0x08
  27 #define REG_IO_CTRL     0x09
  28 #define REG_ENABLE      0x0A
  29 #define REG_FLAG        0x0B
  30 #define REG_MAX         REG_FLAG
  31
  32 struct lm3639_chip_data {
  33         struct device *dev;
  34         struct lm3639_platform_data *pdata;
  35
  36         struct backlight_device *bled;
  37         struct led_classdev cdev_flash;
  38         struct led_classdev cdev_torch;
  39         struct regmap *regmap;
  40
  41         unsigned int bled_mode;
  42         unsigned int bled_map;
  43         unsigned int last_flag;
  44 };
  45
  46 /* initialize chip */
  47 static int lm3639_chip_init(struct lm3639_chip_data *pchip)
  48 {
  49         int ret;
  50         unsigned int reg_val;
  51         struct lm3639_platform_data *pdata = pchip->pdata;
  52
  53         /* input pins config. */
  54         ret =
  55             regmap_update_bits(pchip->regmap, REG_BL_CONF_1, 0x08,
  56                                pdata->pin_pwm);
  57         if (ret < 0)
  58                 goto out;
  59
  60         reg_val = (pdata->pin_pwm & 0x40) | pdata->pin_strobe | pdata->pin_tx;
  61         ret = regmap_update_bits(pchip->regmap, REG_IO_CTRL, 0x7C, reg_val);
  62         if (ret < 0)
  63                 goto out;
  64
  65         /* init brightness */
  66         ret = regmap_write(pchip->regmap, REG_BL_CONF_4, pdata->init_brt_led);
  67         if (ret < 0)
  68                 goto out;
  69
  70         ret = regmap_write(pchip->regmap, REG_BL_CONF_3, pdata->init_brt_led);
  71         if (ret < 0)
  72                 goto out;
  73
  74         /* output pins config. */
  75         if (!pdata->init_brt_led) {
  76                 reg_val = pdata->fled_pins;
  77                 reg_val |= pdata->bled_pins;
  78         } else {
  79                 reg_val = pdata->fled_pins;
  80                 reg_val |= pdata->bled_pins | 0x01;
  81         }
  82
  83         ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x79, reg_val);
  84         if (ret < 0)
  85                 goto out;
  86
  87         return ret;
  88 out:
  89         dev_err(pchip->dev, "i2c failed to access register\n");
  90         return ret;
  91 }
  92
  93 /* update and get brightness */
  94 static int lm3639_bled_update_status(struct backlight_device *bl)
  95 {
  96         int ret;
  97         unsigned int reg_val;
  98         struct lm3639_chip_data *pchip = bl_get_data(bl);
  99         struct lm3639_platform_data *pdata = pchip->pdata;
 100
 101         ret = regmap_read(pchip->regmap, REG_FLAG, &reg_val);
 102         if (ret < 0)
 103                 goto out;
 104
 105         if (reg_val != 0)
 106                 dev_info(pchip->dev, "last flag is 0x%x\n", reg_val);
 107
 108         /* pwm control */
 109         if (pdata->pin_pwm) {
 110                 if (pdata->pwm_set_intensity)
 111                         pdata->pwm_set_intensity(bl->props.brightness,
 112                                                  pdata->max_brt_led);
 113                 else
 114                         dev_err(pchip->dev,
 115                                 "No pwm control func. in plat-data\n");
 116                 return bl->props.brightness;
 117         }
 118
 119         /* i2c control and set brigtness */
 120         ret = regmap_write(pchip->regmap, REG_BL_CONF_4, bl->props.brightness);
 121         if (ret < 0)
 122                 goto out;
 123         ret = regmap_write(pchip->regmap, REG_BL_CONF_3, bl->props.brightness);
 124         if (ret < 0)
 125                 goto out;
 126
 127         if (!bl->props.brightness)
 128                 ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x01, 0x00);
 129         else
 130                 ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x01, 0x01);
 131         if (ret < 0)
 132                 goto out;
 133
 134         return bl->props.brightness;
 135 out:
 136         dev_err(pchip->dev, "i2c failed to access registers\n");
 137         return bl->props.brightness;
 138 }
 139
 140 static int lm3639_bled_get_brightness(struct backlight_device *bl)
 141 {
 142         int ret;
 143         unsigned int reg_val;
 144         struct lm3639_chip_data *pchip = bl_get_data(bl);
 145         struct lm3639_platform_data *pdata = pchip->pdata;
 146
 147         if (pdata->pin_pwm) {
 148                 if (pdata->pwm_get_intensity)
 149                         bl->props.brightness = pdata->pwm_get_intensity();
 150                 else
 151                         dev_err(pchip->dev,
 152                                 "No pwm control func. in plat-data\n");
 153                 return bl->props.brightness;
 154         }
 155
 156         ret = regmap_read(pchip->regmap, REG_BL_CONF_1, &reg_val);
 157         if (ret < 0)
 158                 goto out;
 159         if (reg_val & 0x10)
 160                 ret = regmap_read(pchip->regmap, REG_BL_CONF_4, &reg_val);
 161         else
 162                 ret = regmap_read(pchip->regmap, REG_BL_CONF_3, &reg_val);
 163         if (ret < 0)
 164                 goto out;
 165         bl->props.brightness = reg_val;
 166
 167         return bl->props.brightness;
 168 out:
 169         dev_err(pchip->dev, "i2c failed to access register\n");
 170         return bl->props.brightness;
 171 }
 172
 173 static const struct backlight_ops lm3639_bled_ops = {
 174         .options = BL_CORE_SUSPENDRESUME,
 175         .update_status = lm3639_bled_update_status,
 176         .get_brightness = lm3639_bled_get_brightness,
 177 };
 178
 179 /* backlight mapping mode */
 180 static ssize_t lm3639_bled_mode_store(struct device *dev,
 181                                       struct device_attribute *devAttr,
 182                                       const char *buf, size_t size)
 183 {
 184         ssize_t ret;
 185         struct lm3639_chip_data *pchip = dev_get_drvdata(dev);
 186         unsigned int state;
 187
 188         ret = kstrtouint(buf, 10, &state);
 189         if (ret)
 190                 goto out_input;
 191
 192         if (!state)
 193                 ret =
 194                     regmap_update_bits(pchip->regmap, REG_BL_CONF_1, 0x10,
 195                                        0x00);
 196         else
 197                 ret =
 198                     regmap_update_bits(pchip->regmap, REG_BL_CONF_1, 0x10,
 199                                        0x10);
 200
 201         if (ret < 0)
 202                 goto out;
 203
 204         return size;
 205
 206 out:
 207         dev_err(pchip->dev, "%s:i2c access fail to register\n", __func__);
 208         return ret;
 209
 210 out_input:
 211         dev_err(pchip->dev, "%s:input conversion fail\n", __func__);
 212         return ret;
 213
 214 }
 215
 216 static DEVICE_ATTR(bled_mode, S_IWUSR, NULL, lm3639_bled_mode_store);
 217
 218 /* torch */
 219 static void lm3639_torch_brightness_set(struct led_classdev *cdev,
 220                                         enum led_brightness brightness)
 221 {
 222         int ret;
 223         unsigned int reg_val;
 224         struct lm3639_chip_data *pchip;
 225
 226         pchip = container_of(cdev, struct lm3639_chip_data, cdev_torch);
 227
 228         ret = regmap_read(pchip->regmap, REG_FLAG, &reg_val);
 229         if (ret < 0)
 230                 goto out;
 231         if (reg_val != 0)
 232                 dev_info(pchip->dev, "last flag is 0x%x\n", reg_val);
 233
 234         /* brightness 0 means off state */
 235         if (!brightness) {
 236                 ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x06, 0x00);
 237                 if (ret < 0)
 238                         goto out;
 239                 return;
 240         }
 241
 242         ret = regmap_update_bits(pchip->regmap,
 243                                  REG_FL_CONF_1, 0x70, (brightness - 1) << 4);
 244         if (ret < 0)
 245                 goto out;
 246         ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x06, 0x02);
 247         if (ret < 0)
 248                 goto out;
 249
 250         return;
 251 out:
 252         dev_err(pchip->dev, "i2c failed to access register\n");
 253 }
 254
 255 /* flash */
 256 static void lm3639_flash_brightness_set(struct led_classdev *cdev,
 257                                         enum led_brightness brightness)
 258 {
 259         int ret;
 260         unsigned int reg_val;
 261         struct lm3639_chip_data *pchip;
 262
 263         pchip = container_of(cdev, struct lm3639_chip_data, cdev_flash);
 264
 265         ret = regmap_read(pchip->regmap, REG_FLAG, &reg_val);
 266         if (ret < 0)
 267                 goto out;
 268         if (reg_val != 0)
 269                 dev_info(pchip->dev, "last flag is 0x%x\n", reg_val);
 270
 271         /* torch off before flash control */
 272         ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x06, 0x00);
 273         if (ret < 0)
 274                 goto out;
 275
 276         /* brightness 0 means off state */
 277         if (!brightness)
 278                 return;
 279
 280         ret = regmap_update_bits(pchip->regmap,
 281                                  REG_FL_CONF_1, 0x0F, brightness - 1);
 282         if (ret < 0)
 283                 goto out;
 284         ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x06, 0x06);
 285         if (ret < 0)
 286                 goto out;
 287
 288         return;
 289 out:
 290         dev_err(pchip->dev, "i2c failed to access register\n");
 291 }
 292
 293 static const struct regmap_config lm3639_regmap = {
 294         .reg_bits = 8,
 295         .val_bits = 8,
 296         .max_register = REG_MAX,
 297 };
 298
 299 static int lm3639_probe(struct i2c_client *client,
 300                                   const struct i2c_device_id *id)
 301 {
 302         int ret;
 303         struct lm3639_chip_data *pchip;
 304         struct lm3639_platform_data *pdata = dev_get_platdata(&client->dev);
 305         struct backlight_properties props;
 306
 307         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
 308                 dev_err(&client->dev, "i2c functionality check fail.\n");
 309                 return -EOPNOTSUPP;
 310         }
 311
 312         if (pdata == NULL) {
 313                 dev_err(&client->dev, "Needs Platform Data.\n");
 314                 return -ENODATA;
 315         }
 316
 317         pchip = devm_kzalloc(&client->dev,
 318                              sizeof(struct lm3639_chip_data), GFP_KERNEL);
 319         if (!pchip)
 320                 return -ENOMEM;
 321
 322         pchip->pdata = pdata;
 323         pchip->dev = &client->dev;
 324
 325         pchip->regmap = devm_regmap_init_i2c(client, &lm3639_regmap);
 326         if (IS_ERR(pchip->regmap)) {
 327                 ret = PTR_ERR(pchip->regmap);
 328                 dev_err(&client->dev, "fail : allocate register map: %d\n",
 329                         ret);
 330                 return ret;
 331         }
 332         i2c_set_clientdata(client, pchip);
 333
 334         /* chip initialize */
 335         ret = lm3639_chip_init(pchip);
 336         if (ret < 0) {
 337                 dev_err(&client->dev, "fail : chip init\n");
 338                 goto err_out;
 339         }
 340
 341         /* backlight */
 342         memset(&props, 0, sizeof(struct backlight_properties));
 343         props.type = BACKLIGHT_RAW;
 344         props.brightness = pdata->init_brt_led;
 345         props.max_brightness = pdata->max_brt_led;
 346         pchip->bled =
 347             devm_backlight_device_register(pchip->dev, "lm3639_bled",
 348                                            pchip->dev, pchip, &lm3639_bled_ops,
 349                                            &props);
 350         if (IS_ERR(pchip->bled)) {
 351                 dev_err(&client->dev, "fail : backlight register\n");
 352                 ret = PTR_ERR(pchip->bled);
 353                 goto err_out;
 354         }
 355
 356         ret = device_create_file(&(pchip->bled->dev), &dev_attr_bled_mode);
 357         if (ret < 0) {
 358                 dev_err(&client->dev, "failed : add sysfs entries\n");
 359                 goto err_out;
 360         }
 361
 362         /* flash */
 363         pchip->cdev_flash.name = "lm3639_flash";
 364         pchip->cdev_flash.max_brightness = 16;
 365         pchip->cdev_flash.brightness_set = lm3639_flash_brightness_set;
 366         ret = led_classdev_register((struct device *)
 367                                     &client->dev, &pchip->cdev_flash);
 368         if (ret < 0) {
 369                 dev_err(&client->dev, "fail : flash register\n");
 370                 goto err_flash;
 371         }
 372
 373         /* torch */
 374         pchip->cdev_torch.name = "lm3639_torch";
 375         pchip->cdev_torch.max_brightness = 8;
 376         pchip->cdev_torch.brightness_set = lm3639_torch_brightness_set;
 377         ret = led_classdev_register((struct device *)
 378                                     &client->dev, &pchip->cdev_torch);
 379         if (ret < 0) {
 380                 dev_err(&client->dev, "fail : torch register\n");
 381                 goto err_torch;
 382         }
 383
 384         return 0;
 385
 386 err_torch:
 387         led_classdev_unregister(&pchip->cdev_flash);
 388 err_flash:
 389         device_remove_file(&(pchip->bled->dev), &dev_attr_bled_mode);
 390 err_out:
 391         return ret;
 392 }
 393
 394 static int lm3639_remove(struct i2c_client *client)
 395 {
 396         struct lm3639_chip_data *pchip = i2c_get_clientdata(client);
 397
 398         regmap_write(pchip->regmap, REG_ENABLE, 0x00);
 399
 400         led_classdev_unregister(&pchip->cdev_torch);
 401         led_classdev_unregister(&pchip->cdev_flash);
 402         if (pchip->bled)
 403                 device_remove_file(&(pchip->bled->dev), &dev_attr_bled_mode);
 404         return 0;
 405 }
 406
 407 static const struct i2c_device_id lm3639_id[] = {
 408         {LM3639_NAME, 0},
 409         {}
 410 };
 411
 412 MODULE_DEVICE_TABLE(i2c, lm3639_id);
 413 static struct i2c_driver lm3639_i2c_driver = {
 414         .driver = {
 415                    .name = LM3639_NAME,
 416                    },
 417         .probe = lm3639_probe,
 418         .remove = lm3639_remove,
 419         .id_table = lm3639_id,
 420 };
 421
 422 module_i2c_driver(lm3639_i2c_driver);
 423
 424 MODULE_DESCRIPTION("Texas Instruments Backlight+Flash LED driver for LM3639");
 425 MODULE_AUTHOR("Daniel Jeong <gshark.jeong@gmail.com>");
 426 MODULE_AUTHOR("Ldd Mlp <ldd-mlp@list.ti.com>");
 427 MODULE_LICENSE("GPL v2");