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         int need_pwm;
  56         int 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 };
  86
  87 struct ssd1307fb_array {
  88         u8      type;
  89         u8      data[];
  90 };
  91
  92 static const struct fb_fix_screeninfo ssd1307fb_fix = {
  93         .id             = "Solomon SSD1307",
  94         .type           = FB_TYPE_PACKED_PIXELS,
  95         .visual         = FB_VISUAL_MONO10,
  96         .xpanstep       = 0,
  97         .ypanstep       = 0,
  98         .ywrapstep      = 0,
  99         .accel          = FB_ACCEL_NONE,
 100 };
 101
 102 static const struct fb_var_screeninfo ssd1307fb_var = {
 103         .bits_per_pixel = 1,
 104         .red = { .length = 1 },
 105         .green = { .length = 1 },
 106         .blue = { .length = 1 },
 107 };
 108
 109 static struct ssd1307fb_array *ssd1307fb_alloc_array(u32 len, u8 type)
 110 {
 111         struct ssd1307fb_array *array;
 112
 113         array = kzalloc(sizeof(struct ssd1307fb_array) + len, GFP_KERNEL);
 114         if (!array)
 115                 return NULL;
 116
 117         array->type = type;
 118
 119         return array;
 120 }
 121
 122 static int ssd1307fb_write_array(struct i2c_client *client,
 123                                  struct ssd1307fb_array *array, u32 len)
 124 {
 125         int ret;
 126
 127         len += sizeof(struct ssd1307fb_array);
 128
 129         ret = i2c_master_send(client, (u8 *)array, len);
 130         if (ret != len) {
 131                 dev_err(&client->dev, "Couldn't send I2C command.\n");
 132                 return ret;
 133         }
 134
 135         return 0;
 136 }
 137
 138 static inline int ssd1307fb_write_cmd(struct i2c_client *client, u8 cmd)
 139 {
 140         struct ssd1307fb_array *array;
 141         int ret;
 142
 143         array = ssd1307fb_alloc_array(1, SSD1307FB_COMMAND);
 144         if (!array)
 145                 return -ENOMEM;
 146
 147         array->data[0] = cmd;
 148
 149         ret = ssd1307fb_write_array(client, array, 1);
 150         kfree(array);
 151
 152         return ret;
 153 }
 154
 155 static void ssd1307fb_update_display(struct ssd1307fb_par *par)
 156 {
 157         struct ssd1307fb_array *array;
 158         u8 *vmem = par->info->screen_buffer;
 159         unsigned int line_length = par->info->fix.line_length;
 160         unsigned int pages = DIV_ROUND_UP(par->height, 8);
 161         int i, j, k;
 162
 163         array = ssd1307fb_alloc_array(par->width * pages, SSD1307FB_DATA);
 164         if (!array)
 165                 return;
 166
 167         /*
 168          * The screen is divided in pages, each having a height of 8
 169          * pixels, and the width of the screen. When sending a byte of
 170          * data to the controller, it gives the 8 bits for the current
 171          * column. I.e, the first byte are the 8 bits of the first
 172          * column, then the 8 bits for the second column, etc.
 173          *
 174          *
 175          * Representation of the screen, assuming it is 5 bits
 176          * wide. Each letter-number combination is a bit that controls
 177          * one pixel.
 178          *
 179          * A0 A1 A2 A3 A4
 180          * B0 B1 B2 B3 B4
 181          * C0 C1 C2 C3 C4
 182          * D0 D1 D2 D3 D4
 183          * E0 E1 E2 E3 E4
 184          * F0 F1 F2 F3 F4
 185          * G0 G1 G2 G3 G4
 186          * H0 H1 H2 H3 H4
 187          *
 188          * If you want to update this screen, you need to send 5 bytes:
 189          *  (1) A0 B0 C0 D0 E0 F0 G0 H0
 190          *  (2) A1 B1 C1 D1 E1 F1 G1 H1
 191          *  (3) A2 B2 C2 D2 E2 F2 G2 H2
 192          *  (4) A3 B3 C3 D3 E3 F3 G3 H3
 193          *  (5) A4 B4 C4 D4 E4 F4 G4 H4
 194          */
 195
 196         for (i = 0; i < pages; i++) {
 197                 for (j = 0; j < par->width; j++) {
 198                         int m = 8;
 199                         u32 array_idx = i * par->width + j;
 200                         array->data[array_idx] = 0;
 201                         /* Last page may be partial */
 202                         if (i + 1 == pages && par->height % 8)
 203                                 m = par->height % 8;
 204                         for (k = 0; k < m; k++) {
 205                                 u8 byte = vmem[(8 * i + k) * line_length +
 206                                                j / 8];
 207                                 u8 bit = (byte >> (j % 8)) & 1;
 208                                 array->data[array_idx] |= bit << k;
 209                         }
 210                 }
 211         }
 212
 213         ssd1307fb_write_array(par->client, array, par->width * pages);
 214         kfree(array);
 215 }
 216
 217
 218 static ssize_t ssd1307fb_write(struct fb_info *info, const char __user *buf,
 219                 size_t count, loff_t *ppos)
 220 {
 221         struct ssd1307fb_par *par = info->par;
 222         unsigned long total_size;
 223         unsigned long p = *ppos;
 224         void *dst;
 225
 226         total_size = info->fix.smem_len;
 227
 228         if (p > total_size)
 229                 return -EINVAL;
 230
 231         if (count + p > total_size)
 232                 count = total_size - p;
 233
 234         if (!count)
 235                 return -EINVAL;
 236
 237         dst = info->screen_buffer + p;
 238
 239         if (copy_from_user(dst, buf, count))
 240                 return -EFAULT;
 241
 242         ssd1307fb_update_display(par);
 243
 244         *ppos += count;
 245
 246         return count;
 247 }
 248
 249 static int ssd1307fb_blank(int blank_mode, struct fb_info *info)
 250 {
 251         struct ssd1307fb_par *par = info->par;
 252
 253         if (blank_mode != FB_BLANK_UNBLANK)
 254                 return ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_OFF);
 255         else
 256                 return ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_ON);
 257 }
 258
 259 static void ssd1307fb_fillrect(struct fb_info *info, const struct fb_fillrect *rect)
 260 {
 261         struct ssd1307fb_par *par = info->par;
 262         sys_fillrect(info, rect);
 263         ssd1307fb_update_display(par);
 264 }
 265
 266 static void ssd1307fb_copyarea(struct fb_info *info, const struct fb_copyarea *area)
 267 {
 268         struct ssd1307fb_par *par = info->par;
 269         sys_copyarea(info, area);
 270         ssd1307fb_update_display(par);
 271 }
 272
 273 static void ssd1307fb_imageblit(struct fb_info *info, const struct fb_image *image)
 274 {
 275         struct ssd1307fb_par *par = info->par;
 276         sys_imageblit(info, image);
 277         ssd1307fb_update_display(par);
 278 }
 279
 280 static const struct fb_ops ssd1307fb_ops = {
 281         .owner          = THIS_MODULE,
 282         .fb_read        = fb_sys_read,
 283         .fb_write       = ssd1307fb_write,
 284         .fb_blank       = ssd1307fb_blank,
 285         .fb_fillrect    = ssd1307fb_fillrect,
 286         .fb_copyarea    = ssd1307fb_copyarea,
 287         .fb_imageblit   = ssd1307fb_imageblit,
 288 };
 289
 290 static void ssd1307fb_deferred_io(struct fb_info *info,
 291                                 struct list_head *pagelist)
 292 {
 293         ssd1307fb_update_display(info->par);
 294 }
 295
 296 static int ssd1307fb_init(struct ssd1307fb_par *par)
 297 {
 298         struct pwm_state pwmstate;
 299         int ret;
 300         u32 precharge, dclk, com_invdir, compins;
 301
 302         if (par->device_info->need_pwm) {
 303                 par->pwm = pwm_get(&par->client->dev, NULL);
 304                 if (IS_ERR(par->pwm)) {
 305                         dev_err(&par->client->dev, "Could not get PWM from device tree!\n");
 306                         return PTR_ERR(par->pwm);
 307                 }
 308
 309                 pwm_init_state(par->pwm, &pwmstate);
 310                 pwm_set_relative_duty_cycle(&pwmstate, 50, 100);
 311                 pwm_apply_state(par->pwm, &pwmstate);
 312
 313                 /* Enable the PWM */
 314                 pwm_enable(par->pwm);
 315
 316                 dev_dbg(&par->client->dev, "Using PWM%d with a %lluns period.\n",
 317                         par->pwm->pwm, pwm_get_period(par->pwm));
 318         }
 319
 320         /* Set initial contrast */
 321         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CONTRAST);
 322         if (ret < 0)
 323                 return ret;
 324
 325         ret = ssd1307fb_write_cmd(par->client, par->contrast);
 326         if (ret < 0)
 327                 return ret;
 328
 329         /* Set segment re-map */
 330         if (par->seg_remap) {
 331                 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SEG_REMAP_ON);
 332                 if (ret < 0)
 333                         return ret;
 334         }
 335
 336         /* Set COM direction */
 337         com_invdir = 0xc0 | par->com_invdir << 3;
 338         ret = ssd1307fb_write_cmd(par->client,  com_invdir);
 339         if (ret < 0)
 340                 return ret;
 341
 342         /* Set multiplex ratio value */
 343         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_MULTIPLEX_RATIO);
 344         if (ret < 0)
 345                 return ret;
 346
 347         ret = ssd1307fb_write_cmd(par->client, par->height - 1);
 348         if (ret < 0)
 349                 return ret;
 350
 351         /* set display offset value */
 352         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_DISPLAY_OFFSET);
 353         if (ret < 0)
 354                 return ret;
 355
 356         ret = ssd1307fb_write_cmd(par->client, par->com_offset);
 357         if (ret < 0)
 358                 return ret;
 359
 360         /* Set clock frequency */
 361         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_CLOCK_FREQ);
 362         if (ret < 0)
 363                 return ret;
 364
 365         dclk = ((par->dclk_div - 1) & 0xf) | (par->dclk_frq & 0xf) << 4;
 366         ret = ssd1307fb_write_cmd(par->client, dclk);
 367         if (ret < 0)
 368                 return ret;
 369
 370         /* Set Set Area Color Mode ON/OFF & Low Power Display Mode */
 371         if (par->area_color_enable || par->low_power) {
 372                 u32 mode;
 373
 374                 ret = ssd1307fb_write_cmd(par->client,
 375                                           SSD1307FB_SET_AREA_COLOR_MODE);
 376                 if (ret < 0)
 377                         return ret;
 378
 379                 mode = (par->area_color_enable ? 0x30 : 0) |
 380                         (par->low_power ? 5 : 0);
 381                 ret = ssd1307fb_write_cmd(par->client, mode);
 382                 if (ret < 0)
 383                         return ret;
 384         }
 385
 386         /* Set precharge period in number of ticks from the internal clock */
 387         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_PRECHARGE_PERIOD);
 388         if (ret < 0)
 389                 return ret;
 390
 391         precharge = (par->prechargep1 & 0xf) | (par->prechargep2 & 0xf) << 4;
 392         ret = ssd1307fb_write_cmd(par->client, precharge);
 393         if (ret < 0)
 394                 return ret;
 395
 396         /* Set COM pins configuration */
 397         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_COM_PINS_CONFIG);
 398         if (ret < 0)
 399                 return ret;
 400
 401         compins = 0x02 | !par->com_seq << 4 | par->com_lrremap << 5;
 402         ret = ssd1307fb_write_cmd(par->client, compins);
 403         if (ret < 0)
 404                 return ret;
 405
 406         /* Set VCOMH */
 407         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_VCOMH);
 408         if (ret < 0)
 409                 return ret;
 410
 411         ret = ssd1307fb_write_cmd(par->client, par->vcomh);
 412         if (ret < 0)
 413                 return ret;
 414
 415         /* Turn on the DC-DC Charge Pump */
 416         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CHARGE_PUMP);
 417         if (ret < 0)
 418                 return ret;
 419
 420         ret = ssd1307fb_write_cmd(par->client,
 421                 BIT(4) | (par->device_info->need_chargepump ? BIT(2) : 0));
 422         if (ret < 0)
 423                 return ret;
 424
 425         /* Set lookup table */
 426         if (par->lookup_table_set) {
 427                 int i;
 428
 429                 ret = ssd1307fb_write_cmd(par->client,
 430                                           SSD1307FB_SET_LOOKUP_TABLE);
 431                 if (ret < 0)
 432                         return ret;
 433
 434                 for (i = 0; i < ARRAY_SIZE(par->lookup_table); ++i) {
 435                         u8 val = par->lookup_table[i];
 436
 437                         if (val < 31 || val > 63)
 438                                 dev_warn(&par->client->dev,
 439                                          "lookup table index %d value out of range 31 <= %d <= 63\n",
 440                                          i, val);
 441                         ret = ssd1307fb_write_cmd(par->client, val);
 442                         if (ret < 0)
 443                                 return ret;
 444                 }
 445         }
 446
 447         /* Switch to horizontal addressing mode */
 448         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_ADDRESS_MODE);
 449         if (ret < 0)
 450                 return ret;
 451
 452         ret = ssd1307fb_write_cmd(par->client,
 453                                   SSD1307FB_SET_ADDRESS_MODE_HORIZONTAL);
 454         if (ret < 0)
 455                 return ret;
 456
 457         /* Set column range */
 458         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_COL_RANGE);
 459         if (ret < 0)
 460                 return ret;
 461
 462         ret = ssd1307fb_write_cmd(par->client, par->col_offset);
 463         if (ret < 0)
 464                 return ret;
 465
 466         ret = ssd1307fb_write_cmd(par->client, par->col_offset + par->width - 1);
 467         if (ret < 0)
 468                 return ret;
 469
 470         /* Set page range */
 471         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_PAGE_RANGE);
 472         if (ret < 0)
 473                 return ret;
 474
 475         ret = ssd1307fb_write_cmd(par->client, par->page_offset);
 476         if (ret < 0)
 477                 return ret;
 478
 479         ret = ssd1307fb_write_cmd(par->client,
 480                                   par->page_offset +
 481                                   DIV_ROUND_UP(par->height, 8) - 1);
 482         if (ret < 0)
 483                 return ret;
 484
 485         /* Clear the screen */
 486         ssd1307fb_update_display(par);
 487
 488         /* Turn on the display */
 489         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_ON);
 490         if (ret < 0)
 491                 return ret;
 492
 493         return 0;
 494 }
 495
 496 static int ssd1307fb_update_bl(struct backlight_device *bdev)
 497 {
 498         struct ssd1307fb_par *par = bl_get_data(bdev);
 499         int ret;
 500         int brightness = bdev->props.brightness;
 501
 502         par->contrast = brightness;
 503
 504         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CONTRAST);
 505         if (ret < 0)
 506                 return ret;
 507         ret = ssd1307fb_write_cmd(par->client, par->contrast);
 508         if (ret < 0)
 509                 return ret;
 510         return 0;
 511 }
 512
 513 static int ssd1307fb_get_brightness(struct backlight_device *bdev)
 514 {
 515         struct ssd1307fb_par *par = bl_get_data(bdev);
 516
 517         return par->contrast;
 518 }
 519
 520 static int ssd1307fb_check_fb(struct backlight_device *bdev,
 521                                    struct fb_info *info)
 522 {
 523         return (info->bl_dev == bdev);
 524 }
 525
 526 static const struct backlight_ops ssd1307fb_bl_ops = {
 527         .options        = BL_CORE_SUSPENDRESUME,
 528         .update_status  = ssd1307fb_update_bl,
 529         .get_brightness = ssd1307fb_get_brightness,
 530         .check_fb       = ssd1307fb_check_fb,
 531 };
 532
 533 static struct ssd1307fb_deviceinfo ssd1307fb_ssd1305_deviceinfo = {
 534         .default_vcomh = 0x34,
 535         .default_dclk_div = 1,
 536         .default_dclk_frq = 7,
 537 };
 538
 539 static struct ssd1307fb_deviceinfo ssd1307fb_ssd1306_deviceinfo = {
 540         .default_vcomh = 0x20,
 541         .default_dclk_div = 1,
 542         .default_dclk_frq = 8,
 543         .need_chargepump = 1,
 544 };
 545
 546 static struct ssd1307fb_deviceinfo ssd1307fb_ssd1307_deviceinfo = {
 547         .default_vcomh = 0x20,
 548         .default_dclk_div = 2,
 549         .default_dclk_frq = 12,
 550         .need_pwm = 1,
 551 };
 552
 553 static struct ssd1307fb_deviceinfo ssd1307fb_ssd1309_deviceinfo = {
 554         .default_vcomh = 0x34,
 555         .default_dclk_div = 1,
 556         .default_dclk_frq = 10,
 557 };
 558
 559 static const struct of_device_id ssd1307fb_of_match[] = {
 560         {
 561                 .compatible = "solomon,ssd1305fb-i2c",
 562                 .data = (void *)&ssd1307fb_ssd1305_deviceinfo,
 563         },
 564         {
 565                 .compatible = "solomon,ssd1306fb-i2c",
 566                 .data = (void *)&ssd1307fb_ssd1306_deviceinfo,
 567         },
 568         {
 569                 .compatible = "solomon,ssd1307fb-i2c",
 570                 .data = (void *)&ssd1307fb_ssd1307_deviceinfo,
 571         },
 572         {
 573                 .compatible = "solomon,ssd1309fb-i2c",
 574                 .data = (void *)&ssd1307fb_ssd1309_deviceinfo,
 575         },
 576         {},
 577 };
 578 MODULE_DEVICE_TABLE(of, ssd1307fb_of_match);
 579
 580 static int ssd1307fb_probe(struct i2c_client *client)
 581 {
 582         struct device *dev = &client->dev;
 583         struct backlight_device *bl;
 584         char bl_name[12];
 585         struct fb_info *info;
 586         struct fb_deferred_io *ssd1307fb_defio;
 587         u32 vmem_size;
 588         struct ssd1307fb_par *par;
 589         void *vmem;
 590         int ret;
 591
 592         info = framebuffer_alloc(sizeof(struct ssd1307fb_par), dev);
 593         if (!info)
 594                 return -ENOMEM;
 595
 596         par = info->par;
 597         par->info = info;
 598         par->client = client;
 599
 600         par->device_info = device_get_match_data(dev);
 601
 602         par->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
 603         if (IS_ERR(par->reset)) {
 604                 dev_err(dev, "failed to get reset gpio: %ld\n",
 605                         PTR_ERR(par->reset));
 606                 ret = PTR_ERR(par->reset);
 607                 goto fb_alloc_error;
 608         }
 609
 610         par->vbat_reg = devm_regulator_get_optional(dev, "vbat");
 611         if (IS_ERR(par->vbat_reg)) {
 612                 ret = PTR_ERR(par->vbat_reg);
 613                 if (ret == -ENODEV) {
 614                         par->vbat_reg = NULL;
 615                 } else {
 616                         dev_err(dev, "failed to get VBAT regulator: %d\n", ret);
 617                         goto fb_alloc_error;
 618                 }
 619         }
 620
 621         if (device_property_read_u32(dev, "solomon,width", &par->width))
 622                 par->width = 96;
 623
 624         if (device_property_read_u32(dev, "solomon,height", &par->height))
 625                 par->height = 16;
 626
 627         if (device_property_read_u32(dev, "solomon,page-offset", &par->page_offset))
 628                 par->page_offset = 1;
 629
 630         if (device_property_read_u32(dev, "solomon,col-offset", &par->col_offset))
 631                 par->col_offset = 0;
 632
 633         if (device_property_read_u32(dev, "solomon,com-offset", &par->com_offset))
 634                 par->com_offset = 0;
 635
 636         if (device_property_read_u32(dev, "solomon,prechargep1", &par->prechargep1))
 637                 par->prechargep1 = 2;
 638
 639         if (device_property_read_u32(dev, "solomon,prechargep2", &par->prechargep2))
 640                 par->prechargep2 = 2;
 641
 642         if (!device_property_read_u8_array(dev, "solomon,lookup-table",
 643                                            par->lookup_table,
 644                                            ARRAY_SIZE(par->lookup_table)))
 645                 par->lookup_table_set = 1;
 646
 647         par->seg_remap = !device_property_read_bool(dev, "solomon,segment-no-remap");
 648         par->com_seq = device_property_read_bool(dev, "solomon,com-seq");
 649         par->com_lrremap = device_property_read_bool(dev, "solomon,com-lrremap");
 650         par->com_invdir = device_property_read_bool(dev, "solomon,com-invdir");
 651         par->area_color_enable =
 652                 device_property_read_bool(dev, "solomon,area-color-enable");
 653         par->low_power = device_property_read_bool(dev, "solomon,low-power");
 654
 655         par->contrast = 127;
 656         par->vcomh = par->device_info->default_vcomh;
 657
 658         /* Setup display timing */
 659         if (device_property_read_u32(dev, "solomon,dclk-div", &par->dclk_div))
 660                 par->dclk_div = par->device_info->default_dclk_div;
 661         if (device_property_read_u32(dev, "solomon,dclk-frq", &par->dclk_frq))
 662                 par->dclk_frq = par->device_info->default_dclk_frq;
 663
 664         vmem_size = DIV_ROUND_UP(par->width, 8) * par->height;
 665
 666         vmem = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
 667                                         get_order(vmem_size));
 668         if (!vmem) {
 669                 dev_err(dev, "Couldn't allocate graphical memory.\n");
 670                 ret = -ENOMEM;
 671                 goto fb_alloc_error;
 672         }
 673
 674         ssd1307fb_defio = devm_kzalloc(dev, sizeof(*ssd1307fb_defio),
 675                                        GFP_KERNEL);
 676         if (!ssd1307fb_defio) {
 677                 dev_err(dev, "Couldn't allocate deferred io.\n");
 678                 ret = -ENOMEM;
 679                 goto fb_alloc_error;
 680         }
 681
 682         ssd1307fb_defio->delay = HZ / refreshrate;
 683         ssd1307fb_defio->deferred_io = ssd1307fb_deferred_io;
 684
 685         info->fbops = &ssd1307fb_ops;
 686         info->fix = ssd1307fb_fix;
 687         info->fix.line_length = DIV_ROUND_UP(par->width, 8);
 688         info->fbdefio = ssd1307fb_defio;
 689
 690         info->var = ssd1307fb_var;
 691         info->var.xres = par->width;
 692         info->var.xres_virtual = par->width;
 693         info->var.yres = par->height;
 694         info->var.yres_virtual = par->height;
 695
 696         info->screen_buffer = vmem;
 697         info->fix.smem_start = __pa(vmem);
 698         info->fix.smem_len = vmem_size;
 699
 700         fb_deferred_io_init(info);
 701
 702         i2c_set_clientdata(client, info);
 703
 704         if (par->reset) {
 705                 /* Reset the screen */
 706                 gpiod_set_value_cansleep(par->reset, 1);
 707                 udelay(4);
 708                 gpiod_set_value_cansleep(par->reset, 0);
 709                 udelay(4);
 710         }
 711
 712         if (par->vbat_reg) {
 713                 ret = regulator_enable(par->vbat_reg);
 714                 if (ret) {
 715                         dev_err(dev, "failed to enable VBAT: %d\n", ret);
 716                         goto reset_oled_error;
 717                 }
 718         }
 719
 720         ret = ssd1307fb_init(par);
 721         if (ret)
 722                 goto regulator_enable_error;
 723
 724         ret = register_framebuffer(info);
 725         if (ret) {
 726                 dev_err(dev, "Couldn't register the framebuffer\n");
 727                 goto panel_init_error;
 728         }
 729
 730         snprintf(bl_name, sizeof(bl_name), "ssd1307fb%d", info->node);
 731         bl = backlight_device_register(bl_name, dev, par, &ssd1307fb_bl_ops,
 732                                        NULL);
 733         if (IS_ERR(bl)) {
 734                 ret = PTR_ERR(bl);
 735                 dev_err(dev, "unable to register backlight device: %d\n", ret);
 736                 goto bl_init_error;
 737         }
 738
 739         bl->props.brightness = par->contrast;
 740         bl->props.max_brightness = MAX_CONTRAST;
 741         info->bl_dev = bl;
 742
 743         dev_info(dev, "fb%d: %s framebuffer device registered, using %d bytes of video memory\n", info->node, info->fix.id, vmem_size);
 744
 745         return 0;
 746
 747 bl_init_error:
 748         unregister_framebuffer(info);
 749 panel_init_error:
 750         if (par->device_info->need_pwm) {
 751                 pwm_disable(par->pwm);
 752                 pwm_put(par->pwm);
 753         }
 754 regulator_enable_error:
 755         if (par->vbat_reg)
 756                 regulator_disable(par->vbat_reg);
 757 reset_oled_error:
 758         fb_deferred_io_cleanup(info);
 759 fb_alloc_error:
 760         framebuffer_release(info);
 761         return ret;
 762 }
 763
 764 static int ssd1307fb_remove(struct i2c_client *client)
 765 {
 766         struct fb_info *info = i2c_get_clientdata(client);
 767         struct ssd1307fb_par *par = info->par;
 768
 769         ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_OFF);
 770
 771         backlight_device_unregister(info->bl_dev);
 772
 773         unregister_framebuffer(info);
 774         if (par->device_info->need_pwm) {
 775                 pwm_disable(par->pwm);
 776                 pwm_put(par->pwm);
 777         }
 778         if (par->vbat_reg)
 779                 regulator_disable(par->vbat_reg);
 780         fb_deferred_io_cleanup(info);
 781         __free_pages(__va(info->fix.smem_start), get_order(info->fix.smem_len));
 782         framebuffer_release(info);
 783
 784         return 0;
 785 }
 786
 787 static const struct i2c_device_id ssd1307fb_i2c_id[] = {
 788         { "ssd1305fb", 0 },
 789         { "ssd1306fb", 0 },
 790         { "ssd1307fb", 0 },
 791         { "ssd1309fb", 0 },
 792         { }
 793 };
 794 MODULE_DEVICE_TABLE(i2c, ssd1307fb_i2c_id);
 795
 796 static struct i2c_driver ssd1307fb_driver = {
 797         .probe_new = ssd1307fb_probe,
 798         .remove = ssd1307fb_remove,
 799         .id_table = ssd1307fb_i2c_id,
 800         .driver = {
 801                 .name = "ssd1307fb",
 802                 .of_match_table = ssd1307fb_of_match,
 803         },
 804 };
 805
 806 module_i2c_driver(ssd1307fb_driver);
 807
 808 MODULE_DESCRIPTION("FB driver for the Solomon SSD1307 OLED controller");
 809 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
 810 MODULE_LICENSE("GPL");