drivers/media/i2c/lm3646.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * drivers/media/i2c/lm3646.c
   4  * General device driver for TI lm3646, Dual FLASH LED Driver
   5  *
   6  * Copyright (C) 2014 Texas Instruments
   7  *
   8  * Contact: Daniel Jeong <gshark.jeong@gmail.com>
   9  *                      Ldd-Mlp <ldd-mlp@list.ti.com>
  10  */
  11
  12 #include <linux/delay.h>
  13 #include <linux/i2c.h>
  14 #include <linux/module.h>
  15 #include <linux/slab.h>
  16 #include <linux/regmap.h>
  17 #include <linux/videodev2.h>
  18 #include <media/i2c/lm3646.h>
  19 #include <media/v4l2-ctrls.h>
  20 #include <media/v4l2-device.h>
  21
  22 /* registers definitions */
  23 #define REG_ENABLE              0x01
  24 #define REG_TORCH_BR    0x05
  25 #define REG_FLASH_BR    0x05
  26 #define REG_FLASH_TOUT  0x04
  27 #define REG_FLAG                0x08
  28 #define REG_STROBE_SRC  0x06
  29 #define REG_LED1_FLASH_BR 0x06
  30 #define REG_LED1_TORCH_BR 0x07
  31
  32 #define MASK_ENABLE             0x03
  33 #define MASK_TORCH_BR   0x70
  34 #define MASK_FLASH_BR   0x0F
  35 #define MASK_FLASH_TOUT 0x07
  36 #define MASK_FLAG               0xFF
  37 #define MASK_STROBE_SRC 0x80
  38
  39 /* Fault Mask */
  40 #define FAULT_TIMEOUT   (1<<0)
  41 #define FAULT_SHORT_CIRCUIT     (1<<1)
  42 #define FAULT_UVLO              (1<<2)
  43 #define FAULT_IVFM              (1<<3)
  44 #define FAULT_OCP               (1<<4)
  45 #define FAULT_OVERTEMP  (1<<5)
  46 #define FAULT_NTC_TRIP  (1<<6)
  47 #define FAULT_OVP               (1<<7)
  48
  49 enum led_mode {
  50         MODE_SHDN = 0x0,
  51         MODE_TORCH = 0x2,
  52         MODE_FLASH = 0x3,
  53 };
  54
  55 /*
  56  * struct lm3646_flash
  57  *
  58  * @pdata: platform data
  59  * @regmap: reg. map for i2c
  60  * @lock: muxtex for serial access.
  61  * @led_mode: V4L2 LED mode
  62  * @ctrls_led: V4L2 controls
  63  * @subdev_led: V4L2 subdev
  64  * @mode_reg : mode register value
  65  */
  66 struct lm3646_flash {
  67         struct device *dev;
  68         struct lm3646_platform_data *pdata;
  69         struct regmap *regmap;
  70
  71         struct v4l2_ctrl_handler ctrls_led;
  72         struct v4l2_subdev subdev_led;
  73
  74         u8 mode_reg;
  75 };
  76
  77 #define to_lm3646_flash(_ctrl)  \
  78         container_of(_ctrl->handler, struct lm3646_flash, ctrls_led)
  79
  80 /* enable mode control */
  81 static int lm3646_mode_ctrl(struct lm3646_flash *flash,
  82                             enum v4l2_flash_led_mode led_mode)
  83 {
  84         switch (led_mode) {
  85         case V4L2_FLASH_LED_MODE_NONE:
  86                 return regmap_write(flash->regmap,
  87                                     REG_ENABLE, flash->mode_reg | MODE_SHDN);
  88         case V4L2_FLASH_LED_MODE_TORCH:
  89                 return regmap_write(flash->regmap,
  90                                     REG_ENABLE, flash->mode_reg | MODE_TORCH);
  91         case V4L2_FLASH_LED_MODE_FLASH:
  92                 return regmap_write(flash->regmap,
  93                                     REG_ENABLE, flash->mode_reg | MODE_FLASH);
  94         }
  95         return -EINVAL;
  96 }
  97
  98 /* V4L2 controls  */
  99 static int lm3646_get_ctrl(struct v4l2_ctrl *ctrl)
 100 {
 101         struct lm3646_flash *flash = to_lm3646_flash(ctrl);
 102         unsigned int reg_val;
 103         int rval;
 104
 105         if (ctrl->id != V4L2_CID_FLASH_FAULT)
 106                 return -EINVAL;
 107
 108         rval = regmap_read(flash->regmap, REG_FLAG, &reg_val);
 109         if (rval < 0)
 110                 return rval;
 111
 112         ctrl->val = 0;
 113         if (reg_val & FAULT_TIMEOUT)
 114                 ctrl->val |= V4L2_FLASH_FAULT_TIMEOUT;
 115         if (reg_val & FAULT_SHORT_CIRCUIT)
 116                 ctrl->val |= V4L2_FLASH_FAULT_SHORT_CIRCUIT;
 117         if (reg_val & FAULT_UVLO)
 118                 ctrl->val |= V4L2_FLASH_FAULT_UNDER_VOLTAGE;
 119         if (reg_val & FAULT_IVFM)
 120                 ctrl->val |= V4L2_FLASH_FAULT_INPUT_VOLTAGE;
 121         if (reg_val & FAULT_OCP)
 122                 ctrl->val |= V4L2_FLASH_FAULT_OVER_CURRENT;
 123         if (reg_val & FAULT_OVERTEMP)
 124                 ctrl->val |= V4L2_FLASH_FAULT_OVER_TEMPERATURE;
 125         if (reg_val & FAULT_NTC_TRIP)
 126                 ctrl->val |= V4L2_FLASH_FAULT_LED_OVER_TEMPERATURE;
 127         if (reg_val & FAULT_OVP)
 128                 ctrl->val |= V4L2_FLASH_FAULT_OVER_VOLTAGE;
 129
 130         return 0;
 131 }
 132
 133 static int lm3646_set_ctrl(struct v4l2_ctrl *ctrl)
 134 {
 135         struct lm3646_flash *flash = to_lm3646_flash(ctrl);
 136         unsigned int reg_val;
 137         int rval;
 138
 139         switch (ctrl->id) {
 140         case V4L2_CID_FLASH_LED_MODE:
 141
 142                 if (ctrl->val != V4L2_FLASH_LED_MODE_FLASH)
 143                         return lm3646_mode_ctrl(flash, ctrl->val);
 144                 /* switch to SHDN mode before flash strobe on */
 145                 return lm3646_mode_ctrl(flash, V4L2_FLASH_LED_MODE_NONE);
 146
 147         case V4L2_CID_FLASH_STROBE_SOURCE:
 148                 return regmap_update_bits(flash->regmap,
 149                                           REG_STROBE_SRC, MASK_STROBE_SRC,
 150                                           (ctrl->val) << 7);
 151
 152         case V4L2_CID_FLASH_STROBE:
 153
 154                 /* read and check current mode of chip to start flash */
 155                 rval = regmap_read(flash->regmap, REG_ENABLE, &reg_val);
 156                 if (rval < 0 || ((reg_val & MASK_ENABLE) != MODE_SHDN))
 157                         return rval;
 158                 /* flash on */
 159                 return lm3646_mode_ctrl(flash, V4L2_FLASH_LED_MODE_FLASH);
 160
 161         case V4L2_CID_FLASH_STROBE_STOP:
 162
 163                 /*
 164                  * flash mode will be turned automatically
 165                  * from FLASH mode to SHDN mode after flash duration timeout
 166                  * read and check current mode of chip to stop flash
 167                  */
 168                 rval = regmap_read(flash->regmap, REG_ENABLE, &reg_val);
 169                 if (rval < 0)
 170                         return rval;
 171                 if ((reg_val & MASK_ENABLE) == MODE_FLASH)
 172                         return lm3646_mode_ctrl(flash,
 173                                                 V4L2_FLASH_LED_MODE_NONE);
 174                 return rval;
 175
 176         case V4L2_CID_FLASH_TIMEOUT:
 177                 return regmap_update_bits(flash->regmap,
 178                                           REG_FLASH_TOUT, MASK_FLASH_TOUT,
 179                                           LM3646_FLASH_TOUT_ms_TO_REG
 180                                           (ctrl->val));
 181
 182         case V4L2_CID_FLASH_INTENSITY:
 183                 return regmap_update_bits(flash->regmap,
 184                                           REG_FLASH_BR, MASK_FLASH_BR,
 185                                           LM3646_TOTAL_FLASH_BRT_uA_TO_REG
 186                                           (ctrl->val));
 187
 188         case V4L2_CID_FLASH_TORCH_INTENSITY:
 189                 return regmap_update_bits(flash->regmap,
 190                                           REG_TORCH_BR, MASK_TORCH_BR,
 191                                           LM3646_TOTAL_TORCH_BRT_uA_TO_REG
 192                                           (ctrl->val) << 4);
 193         }
 194
 195         return -EINVAL;
 196 }
 197
 198 static const struct v4l2_ctrl_ops lm3646_led_ctrl_ops = {
 199         .g_volatile_ctrl = lm3646_get_ctrl,
 200         .s_ctrl = lm3646_set_ctrl,
 201 };
 202
 203 static int lm3646_init_controls(struct lm3646_flash *flash)
 204 {
 205         struct v4l2_ctrl *fault;
 206         struct v4l2_ctrl_handler *hdl = &flash->ctrls_led;
 207         const struct v4l2_ctrl_ops *ops = &lm3646_led_ctrl_ops;
 208
 209         v4l2_ctrl_handler_init(hdl, 8);
 210         /* flash mode */
 211         v4l2_ctrl_new_std_menu(hdl, ops, V4L2_CID_FLASH_LED_MODE,
 212                                V4L2_FLASH_LED_MODE_TORCH, ~0x7,
 213                                V4L2_FLASH_LED_MODE_NONE);
 214
 215         /* flash source */
 216         v4l2_ctrl_new_std_menu(hdl, ops, V4L2_CID_FLASH_STROBE_SOURCE,
 217                                0x1, ~0x3, V4L2_FLASH_STROBE_SOURCE_SOFTWARE);
 218
 219         /* flash strobe */
 220         v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_STROBE, 0, 0, 0, 0);
 221         /* flash strobe stop */
 222         v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_STROBE_STOP, 0, 0, 0, 0);
 223
 224         /* flash strobe timeout */
 225         v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_TIMEOUT,
 226                           LM3646_FLASH_TOUT_MIN,
 227                           LM3646_FLASH_TOUT_MAX,
 228                           LM3646_FLASH_TOUT_STEP, flash->pdata->flash_timeout);
 229
 230         /* max flash current */
 231         v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_INTENSITY,
 232                           LM3646_TOTAL_FLASH_BRT_MIN,
 233                           LM3646_TOTAL_FLASH_BRT_MAX,
 234                           LM3646_TOTAL_FLASH_BRT_STEP,
 235                           LM3646_TOTAL_FLASH_BRT_MAX);
 236
 237         /* max torch current */
 238         v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_TORCH_INTENSITY,
 239                           LM3646_TOTAL_TORCH_BRT_MIN,
 240                           LM3646_TOTAL_TORCH_BRT_MAX,
 241                           LM3646_TOTAL_TORCH_BRT_STEP,
 242                           LM3646_TOTAL_TORCH_BRT_MAX);
 243
 244         /* fault */
 245         fault = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_FAULT, 0,
 246                                   V4L2_FLASH_FAULT_OVER_VOLTAGE
 247                                   | V4L2_FLASH_FAULT_OVER_TEMPERATURE
 248                                   | V4L2_FLASH_FAULT_SHORT_CIRCUIT
 249                                   | V4L2_FLASH_FAULT_TIMEOUT, 0, 0);
 250         if (fault != NULL)
 251                 fault->flags |= V4L2_CTRL_FLAG_VOLATILE;
 252
 253         if (hdl->error)
 254                 return hdl->error;
 255
 256         flash->subdev_led.ctrl_handler = hdl;
 257         return 0;
 258 }
 259
 260 /* initialize device */
 261 static const struct v4l2_subdev_ops lm3646_ops = {
 262         .core = NULL,
 263 };
 264
 265 static const struct regmap_config lm3646_regmap = {
 266         .reg_bits = 8,
 267         .val_bits = 8,
 268         .max_register = 0xFF,
 269 };
 270
 271 static int lm3646_subdev_init(struct lm3646_flash *flash)
 272 {
 273         struct i2c_client *client = to_i2c_client(flash->dev);
 274         int rval;
 275
 276         v4l2_i2c_subdev_init(&flash->subdev_led, client, &lm3646_ops);
 277         flash->subdev_led.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
 278         strscpy(flash->subdev_led.name, LM3646_NAME,
 279                 sizeof(flash->subdev_led.name));
 280         rval = lm3646_init_controls(flash);
 281         if (rval)
 282                 goto err_out;
 283         rval = media_entity_pads_init(&flash->subdev_led.entity, 0, NULL);
 284         if (rval < 0)
 285                 goto err_out;
 286         flash->subdev_led.entity.function = MEDIA_ENT_F_FLASH;
 287         return rval;
 288
 289 err_out:
 290         v4l2_ctrl_handler_free(&flash->ctrls_led);
 291         return rval;
 292 }
 293
 294 static int lm3646_init_device(struct lm3646_flash *flash)
 295 {
 296         unsigned int reg_val;
 297         int rval;
 298
 299         /* read the value of mode register to reduce redundant i2c accesses */
 300         rval = regmap_read(flash->regmap, REG_ENABLE, &reg_val);
 301         if (rval < 0)
 302                 return rval;
 303         flash->mode_reg = reg_val & 0xfc;
 304
 305         /* output disable */
 306         rval = lm3646_mode_ctrl(flash, V4L2_FLASH_LED_MODE_NONE);
 307         if (rval < 0)
 308                 return rval;
 309
 310         /*
 311          * LED1 flash current setting
 312          * LED2 flash current = Total(Max) flash current - LED1 flash current
 313          */
 314         rval = regmap_update_bits(flash->regmap,
 315                                   REG_LED1_FLASH_BR, 0x7F,
 316                                   LM3646_LED1_FLASH_BRT_uA_TO_REG
 317                                   (flash->pdata->led1_flash_brt));
 318
 319         if (rval < 0)
 320                 return rval;
 321
 322         /*
 323          * LED1 torch current setting
 324          * LED2 torch current = Total(Max) torch current - LED1 torch current
 325          */
 326         rval = regmap_update_bits(flash->regmap,
 327                                   REG_LED1_TORCH_BR, 0x7F,
 328                                   LM3646_LED1_TORCH_BRT_uA_TO_REG
 329                                   (flash->pdata->led1_torch_brt));
 330         if (rval < 0)
 331                 return rval;
 332
 333         /* Reset flag register */
 334         return regmap_read(flash->regmap, REG_FLAG, &reg_val);
 335 }
 336
 337 static int lm3646_probe(struct i2c_client *client)
 338 {
 339         struct lm3646_flash *flash;
 340         struct lm3646_platform_data *pdata = dev_get_platdata(&client->dev);
 341         int rval;
 342
 343         flash = devm_kzalloc(&client->dev, sizeof(*flash), GFP_KERNEL);
 344         if (flash == NULL)
 345                 return -ENOMEM;
 346
 347         flash->regmap = devm_regmap_init_i2c(client, &lm3646_regmap);
 348         if (IS_ERR(flash->regmap))
 349                 return PTR_ERR(flash->regmap);
 350
 351         /* check device tree if there is no platform data */
 352         if (pdata == NULL) {
 353                 pdata = devm_kzalloc(&client->dev,
 354                                      sizeof(struct lm3646_platform_data),
 355                                      GFP_KERNEL);
 356                 if (pdata == NULL)
 357                         return -ENOMEM;
 358                 /* use default data in case of no platform data */
 359                 pdata->flash_timeout = LM3646_FLASH_TOUT_MAX;
 360                 pdata->led1_torch_brt = LM3646_LED1_TORCH_BRT_MAX;
 361                 pdata->led1_flash_brt = LM3646_LED1_FLASH_BRT_MAX;
 362         }
 363         flash->pdata = pdata;
 364         flash->dev = &client->dev;
 365
 366         rval = lm3646_subdev_init(flash);
 367         if (rval < 0)
 368                 return rval;
 369
 370         rval = lm3646_init_device(flash);
 371         if (rval < 0)
 372                 return rval;
 373
 374         i2c_set_clientdata(client, flash);
 375
 376         return 0;
 377 }
 378
 379 static void lm3646_remove(struct i2c_client *client)
 380 {
 381         struct lm3646_flash *flash = i2c_get_clientdata(client);
 382
 383         v4l2_device_unregister_subdev(&flash->subdev_led);
 384         v4l2_ctrl_handler_free(&flash->ctrls_led);
 385         media_entity_cleanup(&flash->subdev_led.entity);
 386 }
 387
 388 static const struct i2c_device_id lm3646_id_table[] = {
 389         {LM3646_NAME, 0},
 390         {}
 391 };
 392
 393 MODULE_DEVICE_TABLE(i2c, lm3646_id_table);
 394
 395 static struct i2c_driver lm3646_i2c_driver = {
 396         .driver = {
 397                    .name = LM3646_NAME,
 398                    },
 399         .probe = lm3646_probe,
 400         .remove = lm3646_remove,
 401         .id_table = lm3646_id_table,
 402 };
 403
 404 module_i2c_driver(lm3646_i2c_driver);
 405
 406 MODULE_AUTHOR("Daniel Jeong <gshark.jeong@gmail.com>");
 407 MODULE_AUTHOR("Ldd Mlp <ldd-mlp@list.ti.com>");
 408 MODULE_DESCRIPTION("Texas Instruments LM3646 Dual Flash LED driver");
 409 MODULE_LICENSE("GPL");