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         /* 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 ssize_t ssd1307fb_write(struct fb_info *info, const char __user *buf,
 296                 size_t count, loff_t *ppos)
 297 {
 298         struct ssd1307fb_par *par = info->par;
 299         unsigned long total_size;
 300         unsigned long p = *ppos;
 301         void *dst;
 302         int ret;
 303
 304         total_size = info->fix.smem_len;
 305
 306         if (p > total_size)
 307                 return -EINVAL;
 308
 309         if (count + p > total_size)
 310                 count = total_size - p;
 311
 312         if (!count)
 313                 return -EINVAL;
 314
 315         dst = info->screen_buffer + p;
 316
 317         if (copy_from_user(dst, buf, count))
 318                 return -EFAULT;
 319
 320         ret = ssd1307fb_update_display(par);
 321         if (ret < 0)
 322                 return ret;
 323
 324         *ppos += count;
 325
 326         return count;
 327 }
 328
 329 static int ssd1307fb_blank(int blank_mode, struct fb_info *info)
 330 {
 331         struct ssd1307fb_par *par = info->par;
 332
 333         if (blank_mode != FB_BLANK_UNBLANK)
 334                 return ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_OFF);
 335         else
 336                 return ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_ON);
 337 }
 338
 339 static void ssd1307fb_fillrect(struct fb_info *info, const struct fb_fillrect *rect)
 340 {
 341         struct ssd1307fb_par *par = info->par;
 342         sys_fillrect(info, rect);
 343         ssd1307fb_update_rect(par, rect->dx, rect->dy, rect->width,
 344                               rect->height);
 345 }
 346
 347 static void ssd1307fb_copyarea(struct fb_info *info, const struct fb_copyarea *area)
 348 {
 349         struct ssd1307fb_par *par = info->par;
 350         sys_copyarea(info, area);
 351         ssd1307fb_update_rect(par, area->dx, area->dy, area->width,
 352                               area->height);
 353 }
 354
 355 static void ssd1307fb_imageblit(struct fb_info *info, const struct fb_image *image)
 356 {
 357         struct ssd1307fb_par *par = info->par;
 358         sys_imageblit(info, image);
 359         ssd1307fb_update_rect(par, image->dx, image->dy, image->width,
 360                               image->height);
 361 }
 362
 363 static const struct fb_ops ssd1307fb_ops = {
 364         .owner          = THIS_MODULE,
 365         .fb_read        = fb_sys_read,
 366         .fb_write       = ssd1307fb_write,
 367         .fb_blank       = ssd1307fb_blank,
 368         .fb_fillrect    = ssd1307fb_fillrect,
 369         .fb_copyarea    = ssd1307fb_copyarea,
 370         .fb_imageblit   = ssd1307fb_imageblit,
 371         .fb_mmap        = fb_deferred_io_mmap,
 372 };
 373
 374 static void ssd1307fb_deferred_io(struct fb_info *info, struct list_head *pagereflist)
 375 {
 376         ssd1307fb_update_display(info->par);
 377 }
 378
 379 static int ssd1307fb_init(struct ssd1307fb_par *par)
 380 {
 381         struct pwm_state pwmstate;
 382         int ret;
 383         u32 precharge, dclk, com_invdir, compins;
 384
 385         if (par->device_info->need_pwm) {
 386                 par->pwm = pwm_get(&par->client->dev, NULL);
 387                 if (IS_ERR(par->pwm)) {
 388                         dev_err(&par->client->dev, "Could not get PWM from device tree!\n");
 389                         return PTR_ERR(par->pwm);
 390                 }
 391
 392                 pwm_init_state(par->pwm, &pwmstate);
 393                 pwm_set_relative_duty_cycle(&pwmstate, 50, 100);
 394                 pwm_apply_state(par->pwm, &pwmstate);
 395
 396                 /* Enable the PWM */
 397                 pwm_enable(par->pwm);
 398
 399                 dev_dbg(&par->client->dev, "Using PWM%d with a %lluns period.\n",
 400                         par->pwm->pwm, pwm_get_period(par->pwm));
 401         }
 402
 403         /* Set initial contrast */
 404         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CONTRAST);
 405         if (ret < 0)
 406                 return ret;
 407
 408         ret = ssd1307fb_write_cmd(par->client, par->contrast);
 409         if (ret < 0)
 410                 return ret;
 411
 412         /* Set segment re-map */
 413         if (par->seg_remap) {
 414                 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SEG_REMAP_ON);
 415                 if (ret < 0)
 416                         return ret;
 417         }
 418
 419         /* Set COM direction */
 420         com_invdir = 0xc0 | par->com_invdir << 3;
 421         ret = ssd1307fb_write_cmd(par->client,  com_invdir);
 422         if (ret < 0)
 423                 return ret;
 424
 425         /* Set multiplex ratio value */
 426         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_MULTIPLEX_RATIO);
 427         if (ret < 0)
 428                 return ret;
 429
 430         ret = ssd1307fb_write_cmd(par->client, par->height - 1);
 431         if (ret < 0)
 432                 return ret;
 433
 434         /* set display offset value */
 435         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_DISPLAY_OFFSET);
 436         if (ret < 0)
 437                 return ret;
 438
 439         ret = ssd1307fb_write_cmd(par->client, par->com_offset);
 440         if (ret < 0)
 441                 return ret;
 442
 443         /* Set clock frequency */
 444         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_CLOCK_FREQ);
 445         if (ret < 0)
 446                 return ret;
 447
 448         dclk = ((par->dclk_div - 1) & 0xf) | (par->dclk_frq & 0xf) << 4;
 449         ret = ssd1307fb_write_cmd(par->client, dclk);
 450         if (ret < 0)
 451                 return ret;
 452
 453         /* Set Set Area Color Mode ON/OFF & Low Power Display Mode */
 454         if (par->area_color_enable || par->low_power) {
 455                 u32 mode;
 456
 457                 ret = ssd1307fb_write_cmd(par->client,
 458                                           SSD1307FB_SET_AREA_COLOR_MODE);
 459                 if (ret < 0)
 460                         return ret;
 461
 462                 mode = (par->area_color_enable ? 0x30 : 0) |
 463                         (par->low_power ? 5 : 0);
 464                 ret = ssd1307fb_write_cmd(par->client, mode);
 465                 if (ret < 0)
 466                         return ret;
 467         }
 468
 469         /* Set precharge period in number of ticks from the internal clock */
 470         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_PRECHARGE_PERIOD);
 471         if (ret < 0)
 472                 return ret;
 473
 474         precharge = (par->prechargep1 & 0xf) | (par->prechargep2 & 0xf) << 4;
 475         ret = ssd1307fb_write_cmd(par->client, precharge);
 476         if (ret < 0)
 477                 return ret;
 478
 479         /* Set COM pins configuration */
 480         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_COM_PINS_CONFIG);
 481         if (ret < 0)
 482                 return ret;
 483
 484         compins = 0x02 | !par->com_seq << 4 | par->com_lrremap << 5;
 485         ret = ssd1307fb_write_cmd(par->client, compins);
 486         if (ret < 0)
 487                 return ret;
 488
 489         /* Set VCOMH */
 490         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_VCOMH);
 491         if (ret < 0)
 492                 return ret;
 493
 494         ret = ssd1307fb_write_cmd(par->client, par->vcomh);
 495         if (ret < 0)
 496                 return ret;
 497
 498         /* Turn on the DC-DC Charge Pump */
 499         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CHARGE_PUMP);
 500         if (ret < 0)
 501                 return ret;
 502
 503         ret = ssd1307fb_write_cmd(par->client,
 504                 BIT(4) | (par->device_info->need_chargepump ? BIT(2) : 0));
 505         if (ret < 0)
 506                 return ret;
 507
 508         /* Set lookup table */
 509         if (par->lookup_table_set) {
 510                 int i;
 511
 512                 ret = ssd1307fb_write_cmd(par->client,
 513                                           SSD1307FB_SET_LOOKUP_TABLE);
 514                 if (ret < 0)
 515                         return ret;
 516
 517                 for (i = 0; i < ARRAY_SIZE(par->lookup_table); ++i) {
 518                         u8 val = par->lookup_table[i];
 519
 520                         if (val < 31 || val > 63)
 521                                 dev_warn(&par->client->dev,
 522                                          "lookup table index %d value out of range 31 <= %d <= 63\n",
 523                                          i, val);
 524                         ret = ssd1307fb_write_cmd(par->client, val);
 525                         if (ret < 0)
 526                                 return ret;
 527                 }
 528         }
 529
 530         /* Switch to horizontal addressing mode */
 531         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_ADDRESS_MODE);
 532         if (ret < 0)
 533                 return ret;
 534
 535         ret = ssd1307fb_write_cmd(par->client,
 536                                   SSD1307FB_SET_ADDRESS_MODE_HORIZONTAL);
 537         if (ret < 0)
 538                 return ret;
 539
 540         /* Clear the screen */
 541         ret = ssd1307fb_update_display(par);
 542         if (ret < 0)
 543                 return ret;
 544
 545         /* Turn on the display */
 546         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_ON);
 547         if (ret < 0)
 548                 return ret;
 549
 550         return 0;
 551 }
 552
 553 static int ssd1307fb_update_bl(struct backlight_device *bdev)
 554 {
 555         struct ssd1307fb_par *par = bl_get_data(bdev);
 556         int ret;
 557         int brightness = bdev->props.brightness;
 558
 559         par->contrast = brightness;
 560
 561         ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CONTRAST);
 562         if (ret < 0)
 563                 return ret;
 564         ret = ssd1307fb_write_cmd(par->client, par->contrast);
 565         if (ret < 0)
 566                 return ret;
 567         return 0;
 568 }
 569
 570 static int ssd1307fb_get_brightness(struct backlight_device *bdev)
 571 {
 572         struct ssd1307fb_par *par = bl_get_data(bdev);
 573
 574         return par->contrast;
 575 }
 576
 577 static int ssd1307fb_check_fb(struct backlight_device *bdev,
 578                                    struct fb_info *info)
 579 {
 580         return (info->bl_dev == bdev);
 581 }
 582
 583 static const struct backlight_ops ssd1307fb_bl_ops = {
 584         .options        = BL_CORE_SUSPENDRESUME,
 585         .update_status  = ssd1307fb_update_bl,
 586         .get_brightness = ssd1307fb_get_brightness,
 587         .check_fb       = ssd1307fb_check_fb,
 588 };
 589
 590 static struct ssd1307fb_deviceinfo ssd1307fb_ssd1305_deviceinfo = {
 591         .default_vcomh = 0x34,
 592         .default_dclk_div = 1,
 593         .default_dclk_frq = 7,
 594 };
 595
 596 static struct ssd1307fb_deviceinfo ssd1307fb_ssd1306_deviceinfo = {
 597         .default_vcomh = 0x20,
 598         .default_dclk_div = 1,
 599         .default_dclk_frq = 8,
 600         .need_chargepump = 1,
 601 };
 602
 603 static struct ssd1307fb_deviceinfo ssd1307fb_ssd1307_deviceinfo = {
 604         .default_vcomh = 0x20,
 605         .default_dclk_div = 2,
 606         .default_dclk_frq = 12,
 607         .need_pwm = 1,
 608 };
 609
 610 static struct ssd1307fb_deviceinfo ssd1307fb_ssd1309_deviceinfo = {
 611         .default_vcomh = 0x34,
 612         .default_dclk_div = 1,
 613         .default_dclk_frq = 10,
 614 };
 615
 616 static const struct of_device_id ssd1307fb_of_match[] = {
 617         {
 618                 .compatible = "solomon,ssd1305fb-i2c",
 619                 .data = (void *)&ssd1307fb_ssd1305_deviceinfo,
 620         },
 621         {
 622                 .compatible = "solomon,ssd1306fb-i2c",
 623                 .data = (void *)&ssd1307fb_ssd1306_deviceinfo,
 624         },
 625         {
 626                 .compatible = "solomon,ssd1307fb-i2c",
 627                 .data = (void *)&ssd1307fb_ssd1307_deviceinfo,
 628         },
 629         {
 630                 .compatible = "solomon,ssd1309fb-i2c",
 631                 .data = (void *)&ssd1307fb_ssd1309_deviceinfo,
 632         },
 633         {},
 634 };
 635 MODULE_DEVICE_TABLE(of, ssd1307fb_of_match);
 636
 637 static int ssd1307fb_probe(struct i2c_client *client)
 638 {
 639         struct device *dev = &client->dev;
 640         struct backlight_device *bl;
 641         char bl_name[12];
 642         struct fb_info *info;
 643         struct fb_deferred_io *ssd1307fb_defio;
 644         u32 vmem_size;
 645         struct ssd1307fb_par *par;
 646         void *vmem;
 647         int ret;
 648
 649         info = framebuffer_alloc(sizeof(struct ssd1307fb_par), dev);
 650         if (!info)
 651                 return -ENOMEM;
 652
 653         par = info->par;
 654         par->info = info;
 655         par->client = client;
 656
 657         par->device_info = device_get_match_data(dev);
 658
 659         par->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
 660         if (IS_ERR(par->reset)) {
 661                 ret = dev_err_probe(dev, PTR_ERR(par->reset),
 662                                     "failed to get reset gpio\n");
 663                 goto fb_alloc_error;
 664         }
 665
 666         par->vbat_reg = devm_regulator_get_optional(dev, "vbat");
 667         if (IS_ERR(par->vbat_reg)) {
 668                 ret = PTR_ERR(par->vbat_reg);
 669                 if (ret == -ENODEV) {
 670                         par->vbat_reg = NULL;
 671                 } else {
 672                         dev_err_probe(dev, ret, "failed to get VBAT regulator\n");
 673                         goto fb_alloc_error;
 674                 }
 675         }
 676
 677         if (device_property_read_u32(dev, "solomon,width", &par->width))
 678                 par->width = 96;
 679
 680         if (device_property_read_u32(dev, "solomon,height", &par->height))
 681                 par->height = 16;
 682
 683         if (device_property_read_u32(dev, "solomon,page-offset", &par->page_offset))
 684                 par->page_offset = 1;
 685
 686         if (device_property_read_u32(dev, "solomon,col-offset", &par->col_offset))
 687                 par->col_offset = 0;
 688
 689         if (device_property_read_u32(dev, "solomon,com-offset", &par->com_offset))
 690                 par->com_offset = 0;
 691
 692         if (device_property_read_u32(dev, "solomon,prechargep1", &par->prechargep1))
 693                 par->prechargep1 = 2;
 694
 695         if (device_property_read_u32(dev, "solomon,prechargep2", &par->prechargep2))
 696                 par->prechargep2 = 2;
 697
 698         if (!device_property_read_u8_array(dev, "solomon,lookup-table",
 699                                            par->lookup_table,
 700                                            ARRAY_SIZE(par->lookup_table)))
 701                 par->lookup_table_set = 1;
 702
 703         par->seg_remap = !device_property_read_bool(dev, "solomon,segment-no-remap");
 704         par->com_seq = device_property_read_bool(dev, "solomon,com-seq");
 705         par->com_lrremap = device_property_read_bool(dev, "solomon,com-lrremap");
 706         par->com_invdir = device_property_read_bool(dev, "solomon,com-invdir");
 707         par->area_color_enable =
 708                 device_property_read_bool(dev, "solomon,area-color-enable");
 709         par->low_power = device_property_read_bool(dev, "solomon,low-power");
 710
 711         par->contrast = 127;
 712         par->vcomh = par->device_info->default_vcomh;
 713
 714         /* Setup display timing */
 715         if (device_property_read_u32(dev, "solomon,dclk-div", &par->dclk_div))
 716                 par->dclk_div = par->device_info->default_dclk_div;
 717         if (device_property_read_u32(dev, "solomon,dclk-frq", &par->dclk_frq))
 718                 par->dclk_frq = par->device_info->default_dclk_frq;
 719
 720         vmem_size = DIV_ROUND_UP(par->width, 8) * par->height;
 721
 722         vmem = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
 723                                         get_order(vmem_size));
 724         if (!vmem) {
 725                 dev_err(dev, "Couldn't allocate graphical memory.\n");
 726                 ret = -ENOMEM;
 727                 goto fb_alloc_error;
 728         }
 729
 730         ssd1307fb_defio = devm_kzalloc(dev, sizeof(*ssd1307fb_defio),
 731                                        GFP_KERNEL);
 732         if (!ssd1307fb_defio) {
 733                 dev_err(dev, "Couldn't allocate deferred io.\n");
 734                 ret = -ENOMEM;
 735                 goto fb_alloc_error;
 736         }
 737
 738         ssd1307fb_defio->delay = HZ / refreshrate;
 739         ssd1307fb_defio->deferred_io = ssd1307fb_deferred_io;
 740
 741         info->fbops = &ssd1307fb_ops;
 742         info->fix = ssd1307fb_fix;
 743         info->fix.line_length = DIV_ROUND_UP(par->width, 8);
 744         info->fbdefio = ssd1307fb_defio;
 745
 746         info->var = ssd1307fb_var;
 747         info->var.xres = par->width;
 748         info->var.xres_virtual = par->width;
 749         info->var.yres = par->height;
 750         info->var.yres_virtual = par->height;
 751
 752         info->screen_buffer = vmem;
 753         info->fix.smem_start = __pa(vmem);
 754         info->fix.smem_len = vmem_size;
 755
 756         fb_deferred_io_init(info);
 757
 758         i2c_set_clientdata(client, info);
 759
 760         if (par->reset) {
 761                 /* Reset the screen */
 762                 gpiod_set_value_cansleep(par->reset, 1);
 763                 udelay(4);
 764                 gpiod_set_value_cansleep(par->reset, 0);
 765                 udelay(4);
 766         }
 767
 768         if (par->vbat_reg) {
 769                 ret = regulator_enable(par->vbat_reg);
 770                 if (ret) {
 771                         dev_err(dev, "failed to enable VBAT: %d\n", ret);
 772                         goto reset_oled_error;
 773                 }
 774         }
 775
 776         ret = ssd1307fb_init(par);
 777         if (ret)
 778                 goto regulator_enable_error;
 779
 780         ret = register_framebuffer(info);
 781         if (ret) {
 782                 dev_err(dev, "Couldn't register the framebuffer\n");
 783                 goto panel_init_error;
 784         }
 785
 786         snprintf(bl_name, sizeof(bl_name), "ssd1307fb%d", info->node);
 787         bl = backlight_device_register(bl_name, dev, par, &ssd1307fb_bl_ops,
 788                                        NULL);
 789         if (IS_ERR(bl)) {
 790                 ret = PTR_ERR(bl);
 791                 dev_err(dev, "unable to register backlight device: %d\n", ret);
 792                 goto bl_init_error;
 793         }
 794
 795         bl->props.brightness = par->contrast;
 796         bl->props.max_brightness = MAX_CONTRAST;
 797         info->bl_dev = bl;
 798
 799         dev_info(dev, "fb%d: %s framebuffer device registered, using %d bytes of video memory\n", info->node, info->fix.id, vmem_size);
 800
 801         return 0;
 802
 803 bl_init_error:
 804         unregister_framebuffer(info);
 805 panel_init_error:
 806         if (par->device_info->need_pwm) {
 807                 pwm_disable(par->pwm);
 808                 pwm_put(par->pwm);
 809         }
 810 regulator_enable_error:
 811         if (par->vbat_reg)
 812                 regulator_disable(par->vbat_reg);
 813 reset_oled_error:
 814         fb_deferred_io_cleanup(info);
 815 fb_alloc_error:
 816         framebuffer_release(info);
 817         return ret;
 818 }
 819
 820 static int ssd1307fb_remove(struct i2c_client *client)
 821 {
 822         struct fb_info *info = i2c_get_clientdata(client);
 823         struct ssd1307fb_par *par = info->par;
 824
 825         ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_OFF);
 826
 827         backlight_device_unregister(info->bl_dev);
 828
 829         unregister_framebuffer(info);
 830         if (par->device_info->need_pwm) {
 831                 pwm_disable(par->pwm);
 832                 pwm_put(par->pwm);
 833         }
 834         if (par->vbat_reg)
 835                 regulator_disable(par->vbat_reg);
 836         fb_deferred_io_cleanup(info);
 837         __free_pages(__va(info->fix.smem_start), get_order(info->fix.smem_len));
 838         framebuffer_release(info);
 839
 840         return 0;
 841 }
 842
 843 static const struct i2c_device_id ssd1307fb_i2c_id[] = {
 844         { "ssd1305fb", 0 },
 845         { "ssd1306fb", 0 },
 846         { "ssd1307fb", 0 },
 847         { "ssd1309fb", 0 },
 848         { }
 849 };
 850 MODULE_DEVICE_TABLE(i2c, ssd1307fb_i2c_id);
 851
 852 static struct i2c_driver ssd1307fb_driver = {
 853         .probe_new = ssd1307fb_probe,
 854         .remove = ssd1307fb_remove,
 855         .id_table = ssd1307fb_i2c_id,
 856         .driver = {
 857                 .name = "ssd1307fb",
 858                 .of_match_table = ssd1307fb_of_match,
 859         },
 860 };
 861
 862 module_i2c_driver(ssd1307fb_driver);
 863
 864 MODULE_DESCRIPTION("FB driver for the Solomon SSD1307 OLED controller");
 865 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
 866 MODULE_LICENSE("GPL");