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