drivers/video/fbdev/ssd1307fb.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Driver for the Solomon SSD1307 OLED controller
   4  *
   5  * Copyright 2012 Free Electrons
   6  */
   7
   8 #include <linux/backlight.h>
   9 #include <linux/delay.h>
  10 #include <linux/fb.h>
  11 #include <linux/gpio/consumer.h>
  12 #include <linux/i2c.h>
  13 #include <linux/kernel.h>
  14 #include <linux/module.h>
  15 #include <linux/property.h>
  16 #include <linux/pwm.h>
  17 #include <linux/uaccess.h>
  18 #include <linux/regulator/consumer.h>
  19
  20 #define SSD1307FB_DATA                  0x40
  21 #define SSD1307FB_COMMAND               0x80
  22
  23 #define SSD1307FB_SET_ADDRESS_MODE      0x20
  24 #define SSD1307FB_SET_ADDRESS_MODE_HORIZONTAL   (0x00)
  25 #define SSD1307FB_SET_ADDRESS_MODE_VERTICAL     (0x01)
  26 #define SSD1307FB_SET_ADDRESS_MODE_PAGE         (0x02)
  27 #define SSD1307FB_SET_COL_RANGE         0x21
  28 #define SSD1307FB_SET_PAGE_RANGE        0x22
  29 #define SSD1307FB_CONTRAST              0x81
  30 #define SSD1307FB_SET_LOOKUP_TABLE      0x91
  31 #define SSD1307FB_CHARGE_PUMP           0x8d
  32 #define SSD1307FB_SEG_REMAP_ON          0xa1
  33 #define SSD1307FB_DISPLAY_OFF           0xae
  34 #define SSD1307FB_SET_MULTIPLEX_RATIO   0xa8
  35 #define SSD1307FB_DISPLAY_ON            0xaf
  36 #define SSD1307FB_START_PAGE_ADDRESS    0xb0
  37 #define SSD1307FB_SET_DISPLAY_OFFSET    0xd3
  38 #define SSD1307FB_SET_CLOCK_FREQ        0xd5
  39 #define SSD1307FB_SET_AREA_COLOR_MODE   0xd8
  40 #define SSD1307FB_SET_PRECHARGE_PERIOD  0xd9
  41 #define SSD1307FB_SET_COM_PINS_CONFIG   0xda
  42 #define SSD1307FB_SET_VCOMH             0xdb
  43
  44 #define MAX_CONTRAST 255
  45
  46 #define REFRESHRATE 1
  47
  48 static u_int refreshrate = REFRESHRATE;
  49 module_param(refreshrate, uint, 0);
  50
  51 struct ssd1307fb_deviceinfo {
  52         u32 default_vcomh;
  53         u32 default_dclk_div;
  54         u32 default_dclk_frq;
  55         bool need_pwm;
  56         bool need_chargepump;
  57 };
  58
  59 struct ssd1307fb_par {
  60         unsigned area_color_enable : 1;
  61         unsigned com_invdir : 1;
  62         unsigned com_lrremap : 1;
  63         unsigned com_seq : 1;
  64         unsigned lookup_table_set : 1;
  65         unsigned low_power : 1;
  66         unsigned seg_remap : 1;
  67         u32 com_offset;
  68         u32 contrast;
  69         u32 dclk_div;
  70         u32 dclk_frq;
  71         const struct ssd1307fb_deviceinfo *device_info;
  72         struct i2c_client *client;
  73         u32 height;
  74         struct fb_info *info;
  75         u8 lookup_table[4];
  76         u32 page_offset;
  77         u32 col_offset;
  78         u32 prechargep1;
  79         u32 prechargep2;
  80         struct pwm_device *pwm;
  81         struct gpio_desc *reset;
  82         struct regulator *vbat_reg;
  83         u32 vcomh;
  84         u32 width;
  85         /* Cached address ranges */
  86         u8 col_start;
  87         u8 col_end;
  88         u8 page_start;
  89         u8 page_end;
  90 };
  91
  92 struct ssd1307fb_array {
  93         u8      type;
  94         u8      data[];
  95 };
  96
  97 static const struct fb_fix_screeninfo ssd1307fb_fix = {
  98         .id             = "Solomon SSD1307",
  99         .type           = FB_TYPE_PACKED_PIXELS,
 100         .visual         = FB_VISUAL_MONO10,
 101         .xpanstep       = 0,
 102         .ypanstep       = 0,
 103         .ywrapstep      = 0,
 104         .accel          = FB_ACCEL_NONE,
 105 };
 106
 107 static const struct fb_var_screeninfo ssd1307fb_var = {
 108         .bits_per_pixel = 1,
 109         .red = { .length = 1 },
 110         .green = { .length = 1 },
 111         .blue = { .length = 1 },
 112 };
 113
 114 static struct ssd1307fb_array *ssd1307fb_alloc_array(u32 len, u8 type)
 115 {
 116         struct ssd1307fb_array *array;
 117
 118         array = kzalloc(sizeof(struct ssd1307fb_array) + len, GFP_KERNEL);
 119         if (!array)
 120                 return NULL;
 121
 122         array->type = type;
 123
 124         return array;
 125 }
 126
 127 static int ssd1307fb_write_array(struct i2c_client *client,
 128                                  struct ssd1307fb_array *array, u32 len)
 129 {
 130         int ret;
 131
 132         len += sizeof(struct ssd1307fb_array);
 133
 134         ret = i2c_master_send(client, (u8 *)array, len);
 135         if (ret != len) {
 136                 dev_err(&client->dev, "Couldn't send I2C command.\n");
 137                 return ret;
 138         }
 139
 140         return 0;
 141 }
 142
 143 static inline int ssd1307fb_write_cmd(struct i2c_client *client, u8 cmd)
 144 {
 145         struct ssd1307fb_array *array;
 146         int ret;
 147
 148         array = ssd1307fb_alloc_array(1, SSD1307FB_COMMAND);
 149         if (!array)
 150                 return -ENOMEM;
 151
 152         array->data[0] = cmd;
 153
 154         ret = ssd1307fb_write_array(client, array, 1);
 155         kfree(array);
 156
 157         return ret;
 158 }
 159
 160 static int ssd1307fb_set_col_range(struct ssd1307fb_par *par, u8 col_start,
 161                                    u8 cols)
 162 {
 163         u8 col_end = col_start + cols - 1;
 164         int ret;
 165
 166         if (col_start == par->col_start && col_end == par->col_end)
 167                 return 0;
 168
 169         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_COL_RANGE);
 170         if (ret < 0)
 171                 return ret;
 172
 173         ret = ssd1307fb_write_cmd(par->client, col_start);
 174         if (ret < 0)
 175                 return ret;
 176
 177         ret = ssd1307fb_write_cmd(par->client, col_end);
 178         if (ret < 0)
 179                 return ret;
 180
 181         par->col_start = col_start;
 182         par->col_end = col_end;
 183         return 0;
 184 }
 185
 186 static int ssd1307fb_set_page_range(struct ssd1307fb_par *par, u8 page_start,
 187                                     u8 pages)
 188 {
 189         u8 page_end = page_start + pages - 1;
 190         int ret;
 191
 192         if (page_start == par->page_start && page_end == par->page_end)
 193                 return 0;
 194
 195         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_PAGE_RANGE);
 196         if (ret < 0)
 197                 return ret;
 198
 199         ret = ssd1307fb_write_cmd(par->client, page_start);
 200         if (ret < 0)
 201                 return ret;
 202
 203         ret = ssd1307fb_write_cmd(par->client, page_end);
 204         if (ret < 0)
 205                 return ret;
 206
 207         par->page_start = page_start;
 208         par->page_end = page_end;
 209         return 0;
 210 }
 211
 212 static int ssd1307fb_update_rect(struct ssd1307fb_par *par, unsigned int x,
 213                                  unsigned int y, unsigned int width,
 214                                  unsigned int height)
 215 {
 216         struct ssd1307fb_array *array;
 217         u8 *vmem = par->info->screen_buffer;
 218         unsigned int line_length = par->info->fix.line_length;
 219         unsigned int pages = DIV_ROUND_UP(y % 8 + height, 8);
 220         u32 array_idx = 0;
 221         int ret, i, j, k;
 222
 223         array = ssd1307fb_alloc_array(width * pages, SSD1307FB_DATA);
 224         if (!array)
 225                 return -ENOMEM;
 226
 227         /*
 228          * The screen is divided in pages, each having a height of 8
 229          * pixels, and the width of the screen. When sending a byte of
 230          * data to the controller, it gives the 8 bits for the current
 231          * column. I.e, the first byte are the 8 bits of the first
 232          * column, then the 8 bits for the second column, etc.
 233          *
 234          *
 235          * Representation of the screen, assuming it is 5 bits
 236          * wide. Each letter-number combination is a bit that controls
 237          * one pixel.
 238          *
 239          * A0 A1 A2 A3 A4
 240          * B0 B1 B2 B3 B4
 241          * C0 C1 C2 C3 C4
 242          * D0 D1 D2 D3 D4
 243          * E0 E1 E2 E3 E4
 244          * F0 F1 F2 F3 F4
 245          * G0 G1 G2 G3 G4
 246          * H0 H1 H2 H3 H4
 247          *
 248          * If you want to update this screen, you need to send 5 bytes:
 249          *  (1) A0 B0 C0 D0 E0 F0 G0 H0
 250          *  (2) A1 B1 C1 D1 E1 F1 G1 H1
 251          *  (3) A2 B2 C2 D2 E2 F2 G2 H2
 252          *  (4) A3 B3 C3 D3 E3 F3 G3 H3
 253          *  (5) A4 B4 C4 D4 E4 F4 G4 H4
 254          */
 255
 256         ret = ssd1307fb_set_col_range(par, par->col_offset + x, width);
 257         if (ret < 0)
 258                 goto out_free;
 259
 260         ret = ssd1307fb_set_page_range(par, par->page_offset + y / 8, pages);
 261         if (ret < 0)
 262                 goto out_free;
 263
 264         for (i = y / 8; i < y / 8 + pages; i++) {
 265                 int m = 8;
 266
 267                 /* Last page may be partial */
 268                 if (8 * (i + 1) > par->height)
 269                         m = par->height % 8;
 270                 for (j = x; j < x + width; j++) {
 271                         u8 data = 0;
 272
 273                         for (k = 0; k < m; k++) {
 274                                 u8 byte = vmem[(8 * i + k) * line_length +
 275                                                j / 8];
 276                                 u8 bit = (byte >> (j % 8)) & 1;
 277                                 data |= bit << k;
 278                         }
 279                         array->data[array_idx++] = data;
 280                 }
 281         }
 282
 283         ret = ssd1307fb_write_array(par->client, array, width * pages);
 284
 285 out_free:
 286         kfree(array);
 287         return ret;
 288 }
 289
 290 static int ssd1307fb_update_display(struct ssd1307fb_par *par)
 291 {
 292         return ssd1307fb_update_rect(par, 0, 0, par->width, par->height);
 293 }
 294
 295 static int ssd1307fb_blank(int blank_mode, struct fb_info *info)
 296 {
 297         struct ssd1307fb_par *par = info->par;
 298
 299         if (blank_mode != FB_BLANK_UNBLANK)
 300                 return ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_OFF);
 301         else
 302                 return ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_ON);
 303 }
 304
 305 static void ssd1307fb_defio_damage_range(struct fb_info *info, off_t off, size_t len)
 306 {
 307         struct ssd1307fb_par *par = info->par;
 308
 309         ssd1307fb_update_display(par);
 310 }
 311
 312 static void ssd1307fb_defio_damage_area(struct fb_info *info, u32 x, u32 y,
 313                                         u32 width, u32 height)
 314 {
 315         struct ssd1307fb_par *par = info->par;
 316
 317         ssd1307fb_update_rect(par, x, y, width, height);
 318 }
 319
 320 FB_GEN_DEFAULT_DEFERRED_SYSMEM_OPS(ssd1307fb,
 321                                    ssd1307fb_defio_damage_range,
 322                                    ssd1307fb_defio_damage_area)
 323
 324 static const struct fb_ops ssd1307fb_ops = {
 325         .owner          = THIS_MODULE,
 326         FB_DEFAULT_DEFERRED_OPS(ssd1307fb),
 327         .fb_blank       = ssd1307fb_blank,
 328 };
 329
 330 static void ssd1307fb_deferred_io(struct fb_info *info, struct list_head *pagereflist)
 331 {
 332         ssd1307fb_update_display(info->par);
 333 }
 334
 335 static int ssd1307fb_init(struct ssd1307fb_par *par)
 336 {
 337         struct pwm_state pwmstate;
 338         int ret;
 339         u32 precharge, dclk, com_invdir, compins;
 340
 341         if (par->device_info->need_pwm) {
 342                 par->pwm = pwm_get(&par->client->dev, NULL);
 343                 if (IS_ERR(par->pwm)) {
 344                         dev_err(&par->client->dev, "Could not get PWM from device tree!\n");
 345                         return PTR_ERR(par->pwm);
 346                 }
 347
 348                 pwm_init_state(par->pwm, &pwmstate);
 349                 pwm_set_relative_duty_cycle(&pwmstate, 50, 100);
 350                 pwm_apply_might_sleep(par->pwm, &pwmstate);
 351
 352                 /* Enable the PWM */
 353                 pwm_enable(par->pwm);
 354
 355                 dev_dbg(&par->client->dev, "Using PWM %s with a %lluns period.\n",
 356                         par->pwm->label, pwm_get_period(par->pwm));
 357         }
 358
 359         /* Set initial contrast */
 360         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CONTRAST);
 361         if (ret < 0)
 362                 return ret;
 363
 364         ret = ssd1307fb_write_cmd(par->client, par->contrast);
 365         if (ret < 0)
 366                 return ret;
 367
 368         /* Set segment re-map */
 369         if (par->seg_remap) {
 370                 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SEG_REMAP_ON);
 371                 if (ret < 0)
 372                         return ret;
 373         }
 374
 375         /* Set COM direction */
 376         com_invdir = 0xc0 | par->com_invdir << 3;
 377         ret = ssd1307fb_write_cmd(par->client,  com_invdir);
 378         if (ret < 0)
 379                 return ret;
 380
 381         /* Set multiplex ratio value */
 382         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_MULTIPLEX_RATIO);
 383         if (ret < 0)
 384                 return ret;
 385
 386         ret = ssd1307fb_write_cmd(par->client, par->height - 1);
 387         if (ret < 0)
 388                 return ret;
 389
 390         /* set display offset value */
 391         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_DISPLAY_OFFSET);
 392         if (ret < 0)
 393                 return ret;
 394
 395         ret = ssd1307fb_write_cmd(par->client, par->com_offset);
 396         if (ret < 0)
 397                 return ret;
 398
 399         /* Set clock frequency */
 400         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_CLOCK_FREQ);
 401         if (ret < 0)
 402                 return ret;
 403
 404         dclk = ((par->dclk_div - 1) & 0xf) | (par->dclk_frq & 0xf) << 4;
 405         ret = ssd1307fb_write_cmd(par->client, dclk);
 406         if (ret < 0)
 407                 return ret;
 408
 409         /* Set Area Color Mode ON/OFF & Low Power Display Mode */
 410         if (par->area_color_enable || par->low_power) {
 411                 u32 mode;
 412
 413                 ret = ssd1307fb_write_cmd(par->client,
 414                                           SSD1307FB_SET_AREA_COLOR_MODE);
 415                 if (ret < 0)
 416                         return ret;
 417
 418                 mode = (par->area_color_enable ? 0x30 : 0) |
 419                         (par->low_power ? 5 : 0);
 420                 ret = ssd1307fb_write_cmd(par->client, mode);
 421                 if (ret < 0)
 422                         return ret;
 423         }
 424
 425         /* Set precharge period in number of ticks from the internal clock */
 426         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_PRECHARGE_PERIOD);
 427         if (ret < 0)
 428                 return ret;
 429
 430         precharge = (par->prechargep1 & 0xf) | (par->prechargep2 & 0xf) << 4;
 431         ret = ssd1307fb_write_cmd(par->client, precharge);
 432         if (ret < 0)
 433                 return ret;
 434
 435         /* Set COM pins configuration */
 436         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_COM_PINS_CONFIG);
 437         if (ret < 0)
 438                 return ret;
 439
 440         compins = 0x02 | !par->com_seq << 4 | par->com_lrremap << 5;
 441         ret = ssd1307fb_write_cmd(par->client, compins);
 442         if (ret < 0)
 443                 return ret;
 444
 445         /* Set VCOMH */
 446         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_VCOMH);
 447         if (ret < 0)
 448                 return ret;
 449
 450         ret = ssd1307fb_write_cmd(par->client, par->vcomh);
 451         if (ret < 0)
 452                 return ret;
 453
 454         /* Turn on the DC-DC Charge Pump */
 455         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CHARGE_PUMP);
 456         if (ret < 0)
 457                 return ret;
 458
 459         ret = ssd1307fb_write_cmd(par->client,
 460                 BIT(4) | (par->device_info->need_chargepump ? BIT(2) : 0));
 461         if (ret < 0)
 462                 return ret;
 463
 464         /* Set lookup table */
 465         if (par->lookup_table_set) {
 466                 int i;
 467
 468                 ret = ssd1307fb_write_cmd(par->client,
 469                                           SSD1307FB_SET_LOOKUP_TABLE);
 470                 if (ret < 0)
 471                         return ret;
 472
 473                 for (i = 0; i < ARRAY_SIZE(par->lookup_table); ++i) {
 474                         u8 val = par->lookup_table[i];
 475
 476                         if (val < 31 || val > 63)
 477                                 dev_warn(&par->client->dev,
 478                                          "lookup table index %d value out of range 31 <= %d <= 63\n",
 479                                          i, val);
 480                         ret = ssd1307fb_write_cmd(par->client, val);
 481                         if (ret < 0)
 482                                 return ret;
 483                 }
 484         }
 485
 486         /* Switch to horizontal addressing mode */
 487         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_ADDRESS_MODE);
 488         if (ret < 0)
 489                 return ret;
 490
 491         ret = ssd1307fb_write_cmd(par->client,
 492                                   SSD1307FB_SET_ADDRESS_MODE_HORIZONTAL);
 493         if (ret < 0)
 494                 return ret;
 495
 496         /* Clear the screen */
 497         ret = ssd1307fb_update_display(par);
 498         if (ret < 0)
 499                 return ret;
 500
 501         /* Turn on the display */
 502         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_ON);
 503         if (ret < 0)
 504                 return ret;
 505
 506         return 0;
 507 }
 508
 509 static int ssd1307fb_update_bl(struct backlight_device *bdev)
 510 {
 511         struct ssd1307fb_par *par = bl_get_data(bdev);
 512         int ret;
 513         int brightness = bdev->props.brightness;
 514
 515         par->contrast = brightness;
 516
 517         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CONTRAST);
 518         if (ret < 0)
 519                 return ret;
 520         ret = ssd1307fb_write_cmd(par->client, par->contrast);
 521         if (ret < 0)
 522                 return ret;
 523         return 0;
 524 }
 525
 526 static int ssd1307fb_get_brightness(struct backlight_device *bdev)
 527 {
 528         struct ssd1307fb_par *par = bl_get_data(bdev);
 529
 530         return par->contrast;
 531 }
 532
 533 static const struct backlight_ops ssd1307fb_bl_ops = {
 534         .options        = BL_CORE_SUSPENDRESUME,
 535         .update_status  = ssd1307fb_update_bl,
 536         .get_brightness = ssd1307fb_get_brightness,
 537 };
 538
 539 static struct ssd1307fb_deviceinfo ssd1307fb_ssd1305_deviceinfo = {
 540         .default_vcomh = 0x34,
 541         .default_dclk_div = 1,
 542         .default_dclk_frq = 7,
 543 };
 544
 545 static struct ssd1307fb_deviceinfo ssd1307fb_ssd1306_deviceinfo = {
 546         .default_vcomh = 0x20,
 547         .default_dclk_div = 1,
 548         .default_dclk_frq = 8,
 549         .need_chargepump = 1,
 550 };
 551
 552 static struct ssd1307fb_deviceinfo ssd1307fb_ssd1307_deviceinfo = {
 553         .default_vcomh = 0x20,
 554         .default_dclk_div = 2,
 555         .default_dclk_frq = 12,
 556         .need_pwm = 1,
 557 };
 558
 559 static struct ssd1307fb_deviceinfo ssd1307fb_ssd1309_deviceinfo = {
 560         .default_vcomh = 0x34,
 561         .default_dclk_div = 1,
 562         .default_dclk_frq = 10,
 563 };
 564
 565 static const struct of_device_id ssd1307fb_of_match[] = {
 566         {
 567                 .compatible = "solomon,ssd1305fb-i2c",
 568                 .data = (void *)&ssd1307fb_ssd1305_deviceinfo,
 569         },
 570         {
 571                 .compatible = "solomon,ssd1306fb-i2c",
 572                 .data = (void *)&ssd1307fb_ssd1306_deviceinfo,
 573         },
 574         {
 575                 .compatible = "solomon,ssd1307fb-i2c",
 576                 .data = (void *)&ssd1307fb_ssd1307_deviceinfo,
 577         },
 578         {
 579                 .compatible = "solomon,ssd1309fb-i2c",
 580                 .data = (void *)&ssd1307fb_ssd1309_deviceinfo,
 581         },
 582         {},
 583 };
 584 MODULE_DEVICE_TABLE(of, ssd1307fb_of_match);
 585
 586 static int ssd1307fb_probe(struct i2c_client *client)
 587 {
 588         struct device *dev = &client->dev;
 589         struct backlight_device *bl;
 590         struct fb_info *info;
 591         struct fb_deferred_io *ssd1307fb_defio;
 592         u32 vmem_size;
 593         struct ssd1307fb_par *par;
 594         void *vmem;
 595         int ret;
 596
 597         info = framebuffer_alloc(sizeof(struct ssd1307fb_par), dev);
 598         if (!info)
 599                 return -ENOMEM;
 600
 601         par = info->par;
 602         par->info = info;
 603         par->client = client;
 604
 605         par->device_info = device_get_match_data(dev);
 606
 607         par->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
 608         if (IS_ERR(par->reset)) {
 609                 ret = dev_err_probe(dev, PTR_ERR(par->reset),
 610                                     "failed to get reset gpio\n");
 611                 goto fb_alloc_error;
 612         }
 613
 614         par->vbat_reg = devm_regulator_get_optional(dev, "vbat");
 615         if (IS_ERR(par->vbat_reg)) {
 616                 ret = PTR_ERR(par->vbat_reg);
 617                 if (ret == -ENODEV) {
 618                         par->vbat_reg = NULL;
 619                 } else {
 620                         dev_err_probe(dev, ret, "failed to get VBAT regulator\n");
 621                         goto fb_alloc_error;
 622                 }
 623         }
 624
 625         if (device_property_read_u32(dev, "solomon,width", &par->width))
 626                 par->width = 96;
 627
 628         if (device_property_read_u32(dev, "solomon,height", &par->height))
 629                 par->height = 16;
 630
 631         if (device_property_read_u32(dev, "solomon,page-offset", &par->page_offset))
 632                 par->page_offset = 1;
 633
 634         if (device_property_read_u32(dev, "solomon,col-offset", &par->col_offset))
 635                 par->col_offset = 0;
 636
 637         if (device_property_read_u32(dev, "solomon,com-offset", &par->com_offset))
 638                 par->com_offset = 0;
 639
 640         if (device_property_read_u32(dev, "solomon,prechargep1", &par->prechargep1))
 641                 par->prechargep1 = 2;
 642
 643         if (device_property_read_u32(dev, "solomon,prechargep2", &par->prechargep2))
 644                 par->prechargep2 = 2;
 645
 646         if (!device_property_read_u8_array(dev, "solomon,lookup-table",
 647                                            par->lookup_table,
 648                                            ARRAY_SIZE(par->lookup_table)))
 649                 par->lookup_table_set = 1;
 650
 651         par->seg_remap = !device_property_read_bool(dev, "solomon,segment-no-remap");
 652         par->com_seq = device_property_read_bool(dev, "solomon,com-seq");
 653         par->com_lrremap = device_property_read_bool(dev, "solomon,com-lrremap");
 654         par->com_invdir = device_property_read_bool(dev, "solomon,com-invdir");
 655         par->area_color_enable =
 656                 device_property_read_bool(dev, "solomon,area-color-enable");
 657         par->low_power = device_property_read_bool(dev, "solomon,low-power");
 658
 659         par->contrast = 127;
 660         par->vcomh = par->device_info->default_vcomh;
 661
 662         /* Setup display timing */
 663         if (device_property_read_u32(dev, "solomon,dclk-div", &par->dclk_div))
 664                 par->dclk_div = par->device_info->default_dclk_div;
 665         if (device_property_read_u32(dev, "solomon,dclk-frq", &par->dclk_frq))
 666                 par->dclk_frq = par->device_info->default_dclk_frq;
 667
 668         vmem_size = DIV_ROUND_UP(par->width, 8) * par->height;
 669
 670         vmem = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
 671                                         get_order(vmem_size));
 672         if (!vmem) {
 673                 dev_err(dev, "Couldn't allocate graphical memory.\n");
 674                 ret = -ENOMEM;
 675                 goto fb_alloc_error;
 676         }
 677
 678         ssd1307fb_defio = devm_kzalloc(dev, sizeof(*ssd1307fb_defio),
 679                                        GFP_KERNEL);
 680         if (!ssd1307fb_defio) {
 681                 dev_err(dev, "Couldn't allocate deferred io.\n");
 682                 ret = -ENOMEM;
 683                 goto fb_alloc_error;
 684         }
 685
 686         ssd1307fb_defio->delay = HZ / refreshrate;
 687         ssd1307fb_defio->deferred_io = ssd1307fb_deferred_io;
 688
 689         info->fbops = &ssd1307fb_ops;
 690         info->fix = ssd1307fb_fix;
 691         info->fix.line_length = DIV_ROUND_UP(par->width, 8);
 692         info->fbdefio = ssd1307fb_defio;
 693
 694         info->var = ssd1307fb_var;
 695         info->var.xres = par->width;
 696         info->var.xres_virtual = par->width;
 697         info->var.yres = par->height;
 698         info->var.yres_virtual = par->height;
 699
 700         info->screen_buffer = vmem;
 701         info->fix.smem_start = __pa(vmem);
 702         info->fix.smem_len = vmem_size;
 703
 704         fb_deferred_io_init(info);
 705
 706         i2c_set_clientdata(client, info);
 707
 708         if (par->reset) {
 709                 /* Reset the screen */
 710                 gpiod_set_value_cansleep(par->reset, 1);
 711                 udelay(4);
 712                 gpiod_set_value_cansleep(par->reset, 0);
 713                 udelay(4);
 714         }
 715
 716         if (par->vbat_reg) {
 717                 ret = regulator_enable(par->vbat_reg);
 718                 if (ret) {
 719                         dev_err(dev, "failed to enable VBAT: %d\n", ret);
 720                         goto reset_oled_error;
 721                 }
 722         }
 723
 724         ret = ssd1307fb_init(par);
 725         if (ret)
 726                 goto regulator_enable_error;
 727
 728         bl = backlight_device_register("ssd1307fb-bl", dev, par, &ssd1307fb_bl_ops,
 729                                        NULL);
 730         if (IS_ERR(bl)) {
 731                 ret = PTR_ERR(bl);
 732                 dev_err(dev, "unable to register backlight device: %d\n", ret);
 733                 goto panel_init_error;
 734         }
 735         info->bl_dev = bl;
 736
 737         ret = register_framebuffer(info);
 738         if (ret) {
 739                 dev_err(dev, "Couldn't register the framebuffer\n");
 740                 goto fb_init_error;
 741         }
 742
 743         bl->props.brightness = par->contrast;
 744         bl->props.max_brightness = MAX_CONTRAST;
 745
 746         dev_info(dev, "fb%d: %s framebuffer device registered, using %d bytes of video memory\n", info->node, info->fix.id, vmem_size);
 747
 748         return 0;
 749
 750 fb_init_error:
 751         backlight_device_unregister(bl);
 752 panel_init_error:
 753         pwm_disable(par->pwm);
 754         pwm_put(par->pwm);
 755 regulator_enable_error:
 756         if (par->vbat_reg)
 757                 regulator_disable(par->vbat_reg);
 758 reset_oled_error:
 759         fb_deferred_io_cleanup(info);
 760 fb_alloc_error:
 761         framebuffer_release(info);
 762         return ret;
 763 }
 764
 765 static void ssd1307fb_remove(struct i2c_client *client)
 766 {
 767         struct fb_info *info = i2c_get_clientdata(client);
 768         struct ssd1307fb_par *par = info->par;
 769
 770         ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_OFF);
 771
 772         backlight_device_unregister(info->bl_dev);
 773
 774         unregister_framebuffer(info);
 775         pwm_disable(par->pwm);
 776         pwm_put(par->pwm);
 777         if (par->vbat_reg)
 778                 regulator_disable(par->vbat_reg);
 779         fb_deferred_io_cleanup(info);
 780         __free_pages(__va(info->fix.smem_start), get_order(info->fix.smem_len));
 781         framebuffer_release(info);
 782 }
 783
 784 static const struct i2c_device_id ssd1307fb_i2c_id[] = {
 785         { "ssd1305fb" },
 786         { "ssd1306fb" },
 787         { "ssd1307fb" },
 788         { "ssd1309fb" },
 789         { }
 790 };
 791 MODULE_DEVICE_TABLE(i2c, ssd1307fb_i2c_id);
 792
 793 static struct i2c_driver ssd1307fb_driver = {
 794         .probe = ssd1307fb_probe,
 795         .remove = ssd1307fb_remove,
 796         .id_table = ssd1307fb_i2c_id,
 797         .driver = {
 798                 .name = "ssd1307fb",
 799                 .of_match_table = ssd1307fb_of_match,
 800         },
 801 };
 802
 803 module_i2c_driver(ssd1307fb_driver);
 804
 805 MODULE_DESCRIPTION("FB driver for the Solomon SSD1307 OLED controller");
 806 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
 807 MODULE_LICENSE("GPL");