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 }; 372 373 static void ssd1307fb_deferred_io(struct fb_info *info, 374 struct list_head *pagelist) 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 dev_err(dev, "failed to get reset gpio: %ld\n", 662 PTR_ERR(par->reset)); 663 ret = PTR_ERR(par->reset); 664 goto fb_alloc_error; 665 } 666 667 par->vbat_reg = devm_regulator_get_optional(dev, "vbat"); 668 if (IS_ERR(par->vbat_reg)) { 669 ret = PTR_ERR(par->vbat_reg); 670 if (ret == -ENODEV) { 671 par->vbat_reg = NULL; 672 } else { 673 dev_err(dev, "failed to get VBAT regulator: %d\n", ret); 674 goto fb_alloc_error; 675 } 676 } 677 678 if (device_property_read_u32(dev, "solomon,width", &par->width)) 679 par->width = 96; 680 681 if (device_property_read_u32(dev, "solomon,height", &par->height)) 682 par->height = 16; 683 684 if (device_property_read_u32(dev, "solomon,page-offset", &par->page_offset)) 685 par->page_offset = 1; 686 687 if (device_property_read_u32(dev, "solomon,col-offset", &par->col_offset)) 688 par->col_offset = 0; 689 690 if (device_property_read_u32(dev, "solomon,com-offset", &par->com_offset)) 691 par->com_offset = 0; 692 693 if (device_property_read_u32(dev, "solomon,prechargep1", &par->prechargep1)) 694 par->prechargep1 = 2; 695 696 if (device_property_read_u32(dev, "solomon,prechargep2", &par->prechargep2)) 697 par->prechargep2 = 2; 698 699 if (!device_property_read_u8_array(dev, "solomon,lookup-table", 700 par->lookup_table, 701 ARRAY_SIZE(par->lookup_table))) 702 par->lookup_table_set = 1; 703 704 par->seg_remap = !device_property_read_bool(dev, "solomon,segment-no-remap"); 705 par->com_seq = device_property_read_bool(dev, "solomon,com-seq"); 706 par->com_lrremap = device_property_read_bool(dev, "solomon,com-lrremap"); 707 par->com_invdir = device_property_read_bool(dev, "solomon,com-invdir"); 708 par->area_color_enable = 709 device_property_read_bool(dev, "solomon,area-color-enable"); 710 par->low_power = device_property_read_bool(dev, "solomon,low-power"); 711 712 par->contrast = 127; 713 par->vcomh = par->device_info->default_vcomh; 714 715 /* Setup display timing */ 716 if (device_property_read_u32(dev, "solomon,dclk-div", &par->dclk_div)) 717 par->dclk_div = par->device_info->default_dclk_div; 718 if (device_property_read_u32(dev, "solomon,dclk-frq", &par->dclk_frq)) 719 par->dclk_frq = par->device_info->default_dclk_frq; 720 721 vmem_size = DIV_ROUND_UP(par->width, 8) * par->height; 722 723 vmem = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 724 get_order(vmem_size)); 725 if (!vmem) { 726 dev_err(dev, "Couldn't allocate graphical memory.\n"); 727 ret = -ENOMEM; 728 goto fb_alloc_error; 729 } 730 731 ssd1307fb_defio = devm_kzalloc(dev, sizeof(*ssd1307fb_defio), 732 GFP_KERNEL); 733 if (!ssd1307fb_defio) { 734 dev_err(dev, "Couldn't allocate deferred io.\n"); 735 ret = -ENOMEM; 736 goto fb_alloc_error; 737 } 738 739 ssd1307fb_defio->delay = HZ / refreshrate; 740 ssd1307fb_defio->deferred_io = ssd1307fb_deferred_io; 741 742 info->fbops = &ssd1307fb_ops; 743 info->fix = ssd1307fb_fix; 744 info->fix.line_length = DIV_ROUND_UP(par->width, 8); 745 info->fbdefio = ssd1307fb_defio; 746 747 info->var = ssd1307fb_var; 748 info->var.xres = par->width; 749 info->var.xres_virtual = par->width; 750 info->var.yres = par->height; 751 info->var.yres_virtual = par->height; 752 753 info->screen_buffer = vmem; 754 info->fix.smem_start = __pa(vmem); 755 info->fix.smem_len = vmem_size; 756 757 fb_deferred_io_init(info); 758 759 i2c_set_clientdata(client, info); 760 761 if (par->reset) { 762 /* Reset the screen */ 763 gpiod_set_value_cansleep(par->reset, 1); 764 udelay(4); 765 gpiod_set_value_cansleep(par->reset, 0); 766 udelay(4); 767 } 768 769 if (par->vbat_reg) { 770 ret = regulator_enable(par->vbat_reg); 771 if (ret) { 772 dev_err(dev, "failed to enable VBAT: %d\n", ret); 773 goto reset_oled_error; 774 } 775 } 776 777 ret = ssd1307fb_init(par); 778 if (ret) 779 goto regulator_enable_error; 780 781 ret = register_framebuffer(info); 782 if (ret) { 783 dev_err(dev, "Couldn't register the framebuffer\n"); 784 goto panel_init_error; 785 } 786 787 snprintf(bl_name, sizeof(bl_name), "ssd1307fb%d", info->node); 788 bl = backlight_device_register(bl_name, dev, par, &ssd1307fb_bl_ops, 789 NULL); 790 if (IS_ERR(bl)) { 791 ret = PTR_ERR(bl); 792 dev_err(dev, "unable to register backlight device: %d\n", ret); 793 goto bl_init_error; 794 } 795 796 bl->props.brightness = par->contrast; 797 bl->props.max_brightness = MAX_CONTRAST; 798 info->bl_dev = bl; 799 800 dev_info(dev, "fb%d: %s framebuffer device registered, using %d bytes of video memory\n", info->node, info->fix.id, vmem_size); 801 802 return 0; 803 804 bl_init_error: 805 unregister_framebuffer(info); 806 panel_init_error: 807 if (par->device_info->need_pwm) { 808 pwm_disable(par->pwm); 809 pwm_put(par->pwm); 810 } 811 regulator_enable_error: 812 if (par->vbat_reg) 813 regulator_disable(par->vbat_reg); 814 reset_oled_error: 815 fb_deferred_io_cleanup(info); 816 fb_alloc_error: 817 framebuffer_release(info); 818 return ret; 819 } 820 821 static int ssd1307fb_remove(struct i2c_client *client) 822 { 823 struct fb_info *info = i2c_get_clientdata(client); 824 struct ssd1307fb_par *par = info->par; 825 826 ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_OFF); 827 828 backlight_device_unregister(info->bl_dev); 829 830 unregister_framebuffer(info); 831 if (par->device_info->need_pwm) { 832 pwm_disable(par->pwm); 833 pwm_put(par->pwm); 834 } 835 if (par->vbat_reg) 836 regulator_disable(par->vbat_reg); 837 fb_deferred_io_cleanup(info); 838 __free_pages(__va(info->fix.smem_start), get_order(info->fix.smem_len)); 839 framebuffer_release(info); 840 841 return 0; 842 } 843 844 static const struct i2c_device_id ssd1307fb_i2c_id[] = { 845 { "ssd1305fb", 0 }, 846 { "ssd1306fb", 0 }, 847 { "ssd1307fb", 0 }, 848 { "ssd1309fb", 0 }, 849 { } 850 }; 851 MODULE_DEVICE_TABLE(i2c, ssd1307fb_i2c_id); 852 853 static struct i2c_driver ssd1307fb_driver = { 854 .probe_new = ssd1307fb_probe, 855 .remove = ssd1307fb_remove, 856 .id_table = ssd1307fb_i2c_id, 857 .driver = { 858 .name = "ssd1307fb", 859 .of_match_table = ssd1307fb_of_match, 860 }, 861 }; 862 863 module_i2c_driver(ssd1307fb_driver); 864 865 MODULE_DESCRIPTION("FB driver for the Solomon SSD1307 OLED controller"); 866 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>"); 867 MODULE_LICENSE("GPL"); 868