1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Driver for the Solomon SSD1307 OLED controller 4 * 5 * Copyright 2012 Free Electrons 6 */ 7 8 #include <linux/backlight.h> 9 #include <linux/delay.h> 10 #include <linux/fb.h> 11 #include <linux/gpio/consumer.h> 12 #include <linux/i2c.h> 13 #include <linux/kernel.h> 14 #include <linux/module.h> 15 #include <linux/property.h> 16 #include <linux/pwm.h> 17 #include <linux/uaccess.h> 18 #include <linux/regulator/consumer.h> 19 20 #define SSD1307FB_DATA 0x40 21 #define SSD1307FB_COMMAND 0x80 22 23 #define SSD1307FB_SET_ADDRESS_MODE 0x20 24 #define SSD1307FB_SET_ADDRESS_MODE_HORIZONTAL (0x00) 25 #define SSD1307FB_SET_ADDRESS_MODE_VERTICAL (0x01) 26 #define SSD1307FB_SET_ADDRESS_MODE_PAGE (0x02) 27 #define SSD1307FB_SET_COL_RANGE 0x21 28 #define SSD1307FB_SET_PAGE_RANGE 0x22 29 #define SSD1307FB_CONTRAST 0x81 30 #define SSD1307FB_SET_LOOKUP_TABLE 0x91 31 #define SSD1307FB_CHARGE_PUMP 0x8d 32 #define SSD1307FB_SEG_REMAP_ON 0xa1 33 #define SSD1307FB_DISPLAY_OFF 0xae 34 #define SSD1307FB_SET_MULTIPLEX_RATIO 0xa8 35 #define SSD1307FB_DISPLAY_ON 0xaf 36 #define SSD1307FB_START_PAGE_ADDRESS 0xb0 37 #define SSD1307FB_SET_DISPLAY_OFFSET 0xd3 38 #define SSD1307FB_SET_CLOCK_FREQ 0xd5 39 #define SSD1307FB_SET_AREA_COLOR_MODE 0xd8 40 #define SSD1307FB_SET_PRECHARGE_PERIOD 0xd9 41 #define SSD1307FB_SET_COM_PINS_CONFIG 0xda 42 #define SSD1307FB_SET_VCOMH 0xdb 43 44 #define MAX_CONTRAST 255 45 46 #define REFRESHRATE 1 47 48 static u_int refreshrate = REFRESHRATE; 49 module_param(refreshrate, uint, 0); 50 51 struct ssd1307fb_deviceinfo { 52 u32 default_vcomh; 53 u32 default_dclk_div; 54 u32 default_dclk_frq; 55 bool need_pwm; 56 bool need_chargepump; 57 }; 58 59 struct ssd1307fb_par { 60 unsigned area_color_enable : 1; 61 unsigned com_invdir : 1; 62 unsigned com_lrremap : 1; 63 unsigned com_seq : 1; 64 unsigned lookup_table_set : 1; 65 unsigned low_power : 1; 66 unsigned seg_remap : 1; 67 u32 com_offset; 68 u32 contrast; 69 u32 dclk_div; 70 u32 dclk_frq; 71 const struct ssd1307fb_deviceinfo *device_info; 72 struct i2c_client *client; 73 u32 height; 74 struct fb_info *info; 75 u8 lookup_table[4]; 76 u32 page_offset; 77 u32 col_offset; 78 u32 prechargep1; 79 u32 prechargep2; 80 struct pwm_device *pwm; 81 struct gpio_desc *reset; 82 struct regulator *vbat_reg; 83 u32 vcomh; 84 u32 width; 85 /* Cached address ranges */ 86 u8 col_start; 87 u8 col_end; 88 u8 page_start; 89 u8 page_end; 90 }; 91 92 struct ssd1307fb_array { 93 u8 type; 94 u8 data[]; 95 }; 96 97 static const struct fb_fix_screeninfo ssd1307fb_fix = { 98 .id = "Solomon SSD1307", 99 .type = FB_TYPE_PACKED_PIXELS, 100 .visual = FB_VISUAL_MONO10, 101 .xpanstep = 0, 102 .ypanstep = 0, 103 .ywrapstep = 0, 104 .accel = FB_ACCEL_NONE, 105 }; 106 107 static const struct fb_var_screeninfo ssd1307fb_var = { 108 .bits_per_pixel = 1, 109 .red = { .length = 1 }, 110 .green = { .length = 1 }, 111 .blue = { .length = 1 }, 112 }; 113 114 static struct ssd1307fb_array *ssd1307fb_alloc_array(u32 len, u8 type) 115 { 116 struct ssd1307fb_array *array; 117 118 array = kzalloc(sizeof(struct ssd1307fb_array) + len, GFP_KERNEL); 119 if (!array) 120 return NULL; 121 122 array->type = type; 123 124 return array; 125 } 126 127 static int ssd1307fb_write_array(struct i2c_client *client, 128 struct ssd1307fb_array *array, u32 len) 129 { 130 int ret; 131 132 len += sizeof(struct ssd1307fb_array); 133 134 ret = i2c_master_send(client, (u8 *)array, len); 135 if (ret != len) { 136 dev_err(&client->dev, "Couldn't send I2C command.\n"); 137 return ret; 138 } 139 140 return 0; 141 } 142 143 static inline int ssd1307fb_write_cmd(struct i2c_client *client, u8 cmd) 144 { 145 struct ssd1307fb_array *array; 146 int ret; 147 148 array = ssd1307fb_alloc_array(1, SSD1307FB_COMMAND); 149 if (!array) 150 return -ENOMEM; 151 152 array->data[0] = cmd; 153 154 ret = ssd1307fb_write_array(client, array, 1); 155 kfree(array); 156 157 return ret; 158 } 159 160 static int ssd1307fb_set_col_range(struct ssd1307fb_par *par, u8 col_start, 161 u8 cols) 162 { 163 u8 col_end = col_start + cols - 1; 164 int ret; 165 166 if (col_start == par->col_start && col_end == par->col_end) 167 return 0; 168 169 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_COL_RANGE); 170 if (ret < 0) 171 return ret; 172 173 ret = ssd1307fb_write_cmd(par->client, col_start); 174 if (ret < 0) 175 return ret; 176 177 ret = ssd1307fb_write_cmd(par->client, col_end); 178 if (ret < 0) 179 return ret; 180 181 par->col_start = col_start; 182 par->col_end = col_end; 183 return 0; 184 } 185 186 static int ssd1307fb_set_page_range(struct ssd1307fb_par *par, u8 page_start, 187 u8 pages) 188 { 189 u8 page_end = page_start + pages - 1; 190 int ret; 191 192 if (page_start == par->page_start && page_end == par->page_end) 193 return 0; 194 195 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_PAGE_RANGE); 196 if (ret < 0) 197 return ret; 198 199 ret = ssd1307fb_write_cmd(par->client, page_start); 200 if (ret < 0) 201 return ret; 202 203 ret = ssd1307fb_write_cmd(par->client, page_end); 204 if (ret < 0) 205 return ret; 206 207 par->page_start = page_start; 208 par->page_end = page_end; 209 return 0; 210 } 211 212 static int ssd1307fb_update_rect(struct ssd1307fb_par *par, unsigned int x, 213 unsigned int y, unsigned int width, 214 unsigned int height) 215 { 216 struct ssd1307fb_array *array; 217 u8 *vmem = par->info->screen_buffer; 218 unsigned int line_length = par->info->fix.line_length; 219 unsigned int pages = DIV_ROUND_UP(y % 8 + height, 8); 220 u32 array_idx = 0; 221 int ret, i, j, k; 222 223 array = ssd1307fb_alloc_array(width * pages, SSD1307FB_DATA); 224 if (!array) 225 return -ENOMEM; 226 227 /* 228 * The screen is divided in pages, each having a height of 8 229 * pixels, and the width of the screen. When sending a byte of 230 * data to the controller, it gives the 8 bits for the current 231 * column. I.e, the first byte are the 8 bits of the first 232 * column, then the 8 bits for the second column, etc. 233 * 234 * 235 * Representation of the screen, assuming it is 5 bits 236 * wide. Each letter-number combination is a bit that controls 237 * one pixel. 238 * 239 * A0 A1 A2 A3 A4 240 * B0 B1 B2 B3 B4 241 * C0 C1 C2 C3 C4 242 * D0 D1 D2 D3 D4 243 * E0 E1 E2 E3 E4 244 * F0 F1 F2 F3 F4 245 * G0 G1 G2 G3 G4 246 * H0 H1 H2 H3 H4 247 * 248 * If you want to update this screen, you need to send 5 bytes: 249 * (1) A0 B0 C0 D0 E0 F0 G0 H0 250 * (2) A1 B1 C1 D1 E1 F1 G1 H1 251 * (3) A2 B2 C2 D2 E2 F2 G2 H2 252 * (4) A3 B3 C3 D3 E3 F3 G3 H3 253 * (5) A4 B4 C4 D4 E4 F4 G4 H4 254 */ 255 256 ret = ssd1307fb_set_col_range(par, par->col_offset + x, width); 257 if (ret < 0) 258 goto out_free; 259 260 ret = ssd1307fb_set_page_range(par, par->page_offset + y / 8, pages); 261 if (ret < 0) 262 goto out_free; 263 264 for (i = y / 8; i < y / 8 + pages; i++) { 265 int m = 8; 266 267 /* Last page may be partial */ 268 if (8 * (i + 1) > par->height) 269 m = par->height % 8; 270 for (j = x; j < x + width; j++) { 271 u8 data = 0; 272 273 for (k = 0; k < m; k++) { 274 u8 byte = vmem[(8 * i + k) * line_length + 275 j / 8]; 276 u8 bit = (byte >> (j % 8)) & 1; 277 data |= bit << k; 278 } 279 array->data[array_idx++] = data; 280 } 281 } 282 283 ret = ssd1307fb_write_array(par->client, array, width * pages); 284 285 out_free: 286 kfree(array); 287 return ret; 288 } 289 290 static int ssd1307fb_update_display(struct ssd1307fb_par *par) 291 { 292 return ssd1307fb_update_rect(par, 0, 0, par->width, par->height); 293 } 294 295 static int ssd1307fb_blank(int blank_mode, struct fb_info *info) 296 { 297 struct ssd1307fb_par *par = info->par; 298 299 if (blank_mode != FB_BLANK_UNBLANK) 300 return ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_OFF); 301 else 302 return ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_ON); 303 } 304 305 static void ssd1307fb_defio_damage_range(struct fb_info *info, off_t off, size_t len) 306 { 307 struct ssd1307fb_par *par = info->par; 308 309 ssd1307fb_update_display(par); 310 } 311 312 static void ssd1307fb_defio_damage_area(struct fb_info *info, u32 x, u32 y, 313 u32 width, u32 height) 314 { 315 struct ssd1307fb_par *par = info->par; 316 317 ssd1307fb_update_rect(par, x, y, width, height); 318 } 319 320 FB_GEN_DEFAULT_DEFERRED_SYSMEM_OPS(ssd1307fb, 321 ssd1307fb_defio_damage_range, 322 ssd1307fb_defio_damage_area) 323 324 static const struct fb_ops ssd1307fb_ops = { 325 .owner = THIS_MODULE, 326 FB_DEFAULT_DEFERRED_OPS(ssd1307fb), 327 .fb_blank = ssd1307fb_blank, 328 }; 329 330 static void ssd1307fb_deferred_io(struct fb_info *info, struct list_head *pagereflist) 331 { 332 ssd1307fb_update_display(info->par); 333 } 334 335 static int ssd1307fb_init(struct ssd1307fb_par *par) 336 { 337 struct pwm_state pwmstate; 338 int ret; 339 u32 precharge, dclk, com_invdir, compins; 340 341 if (par->device_info->need_pwm) { 342 par->pwm = pwm_get(&par->client->dev, NULL); 343 if (IS_ERR(par->pwm)) { 344 dev_err(&par->client->dev, "Could not get PWM from device tree!\n"); 345 return PTR_ERR(par->pwm); 346 } 347 348 pwm_init_state(par->pwm, &pwmstate); 349 pwm_set_relative_duty_cycle(&pwmstate, 50, 100); 350 pwm_apply_state(par->pwm, &pwmstate); 351 352 /* Enable the PWM */ 353 pwm_enable(par->pwm); 354 355 dev_dbg(&par->client->dev, "Using PWM %s with a %lluns period.\n", 356 par->pwm->label, pwm_get_period(par->pwm)); 357 } 358 359 /* Set initial contrast */ 360 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CONTRAST); 361 if (ret < 0) 362 return ret; 363 364 ret = ssd1307fb_write_cmd(par->client, par->contrast); 365 if (ret < 0) 366 return ret; 367 368 /* Set segment re-map */ 369 if (par->seg_remap) { 370 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SEG_REMAP_ON); 371 if (ret < 0) 372 return ret; 373 } 374 375 /* Set COM direction */ 376 com_invdir = 0xc0 | par->com_invdir << 3; 377 ret = ssd1307fb_write_cmd(par->client, com_invdir); 378 if (ret < 0) 379 return ret; 380 381 /* Set multiplex ratio value */ 382 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_MULTIPLEX_RATIO); 383 if (ret < 0) 384 return ret; 385 386 ret = ssd1307fb_write_cmd(par->client, par->height - 1); 387 if (ret < 0) 388 return ret; 389 390 /* set display offset value */ 391 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_DISPLAY_OFFSET); 392 if (ret < 0) 393 return ret; 394 395 ret = ssd1307fb_write_cmd(par->client, par->com_offset); 396 if (ret < 0) 397 return ret; 398 399 /* Set clock frequency */ 400 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_CLOCK_FREQ); 401 if (ret < 0) 402 return ret; 403 404 dclk = ((par->dclk_div - 1) & 0xf) | (par->dclk_frq & 0xf) << 4; 405 ret = ssd1307fb_write_cmd(par->client, dclk); 406 if (ret < 0) 407 return ret; 408 409 /* Set Area Color Mode ON/OFF & Low Power Display Mode */ 410 if (par->area_color_enable || par->low_power) { 411 u32 mode; 412 413 ret = ssd1307fb_write_cmd(par->client, 414 SSD1307FB_SET_AREA_COLOR_MODE); 415 if (ret < 0) 416 return ret; 417 418 mode = (par->area_color_enable ? 0x30 : 0) | 419 (par->low_power ? 5 : 0); 420 ret = ssd1307fb_write_cmd(par->client, mode); 421 if (ret < 0) 422 return ret; 423 } 424 425 /* Set precharge period in number of ticks from the internal clock */ 426 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_PRECHARGE_PERIOD); 427 if (ret < 0) 428 return ret; 429 430 precharge = (par->prechargep1 & 0xf) | (par->prechargep2 & 0xf) << 4; 431 ret = ssd1307fb_write_cmd(par->client, precharge); 432 if (ret < 0) 433 return ret; 434 435 /* Set COM pins configuration */ 436 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_COM_PINS_CONFIG); 437 if (ret < 0) 438 return ret; 439 440 compins = 0x02 | !par->com_seq << 4 | par->com_lrremap << 5; 441 ret = ssd1307fb_write_cmd(par->client, compins); 442 if (ret < 0) 443 return ret; 444 445 /* Set VCOMH */ 446 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_VCOMH); 447 if (ret < 0) 448 return ret; 449 450 ret = ssd1307fb_write_cmd(par->client, par->vcomh); 451 if (ret < 0) 452 return ret; 453 454 /* Turn on the DC-DC Charge Pump */ 455 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CHARGE_PUMP); 456 if (ret < 0) 457 return ret; 458 459 ret = ssd1307fb_write_cmd(par->client, 460 BIT(4) | (par->device_info->need_chargepump ? BIT(2) : 0)); 461 if (ret < 0) 462 return ret; 463 464 /* Set lookup table */ 465 if (par->lookup_table_set) { 466 int i; 467 468 ret = ssd1307fb_write_cmd(par->client, 469 SSD1307FB_SET_LOOKUP_TABLE); 470 if (ret < 0) 471 return ret; 472 473 for (i = 0; i < ARRAY_SIZE(par->lookup_table); ++i) { 474 u8 val = par->lookup_table[i]; 475 476 if (val < 31 || val > 63) 477 dev_warn(&par->client->dev, 478 "lookup table index %d value out of range 31 <= %d <= 63\n", 479 i, val); 480 ret = ssd1307fb_write_cmd(par->client, val); 481 if (ret < 0) 482 return ret; 483 } 484 } 485 486 /* Switch to horizontal addressing mode */ 487 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_ADDRESS_MODE); 488 if (ret < 0) 489 return ret; 490 491 ret = ssd1307fb_write_cmd(par->client, 492 SSD1307FB_SET_ADDRESS_MODE_HORIZONTAL); 493 if (ret < 0) 494 return ret; 495 496 /* Clear the screen */ 497 ret = ssd1307fb_update_display(par); 498 if (ret < 0) 499 return ret; 500 501 /* Turn on the display */ 502 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_ON); 503 if (ret < 0) 504 return ret; 505 506 return 0; 507 } 508 509 static int ssd1307fb_update_bl(struct backlight_device *bdev) 510 { 511 struct ssd1307fb_par *par = bl_get_data(bdev); 512 int ret; 513 int brightness = bdev->props.brightness; 514 515 par->contrast = brightness; 516 517 ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CONTRAST); 518 if (ret < 0) 519 return ret; 520 ret = ssd1307fb_write_cmd(par->client, par->contrast); 521 if (ret < 0) 522 return ret; 523 return 0; 524 } 525 526 static int ssd1307fb_get_brightness(struct backlight_device *bdev) 527 { 528 struct ssd1307fb_par *par = bl_get_data(bdev); 529 530 return par->contrast; 531 } 532 533 static int ssd1307fb_check_fb(struct backlight_device *bdev, 534 struct fb_info *info) 535 { 536 return (info->bl_dev == bdev); 537 } 538 539 static const struct backlight_ops ssd1307fb_bl_ops = { 540 .options = BL_CORE_SUSPENDRESUME, 541 .update_status = ssd1307fb_update_bl, 542 .get_brightness = ssd1307fb_get_brightness, 543 .check_fb = ssd1307fb_check_fb, 544 }; 545 546 static struct ssd1307fb_deviceinfo ssd1307fb_ssd1305_deviceinfo = { 547 .default_vcomh = 0x34, 548 .default_dclk_div = 1, 549 .default_dclk_frq = 7, 550 }; 551 552 static struct ssd1307fb_deviceinfo ssd1307fb_ssd1306_deviceinfo = { 553 .default_vcomh = 0x20, 554 .default_dclk_div = 1, 555 .default_dclk_frq = 8, 556 .need_chargepump = 1, 557 }; 558 559 static struct ssd1307fb_deviceinfo ssd1307fb_ssd1307_deviceinfo = { 560 .default_vcomh = 0x20, 561 .default_dclk_div = 2, 562 .default_dclk_frq = 12, 563 .need_pwm = 1, 564 }; 565 566 static struct ssd1307fb_deviceinfo ssd1307fb_ssd1309_deviceinfo = { 567 .default_vcomh = 0x34, 568 .default_dclk_div = 1, 569 .default_dclk_frq = 10, 570 }; 571 572 static const struct of_device_id ssd1307fb_of_match[] = { 573 { 574 .compatible = "solomon,ssd1305fb-i2c", 575 .data = (void *)&ssd1307fb_ssd1305_deviceinfo, 576 }, 577 { 578 .compatible = "solomon,ssd1306fb-i2c", 579 .data = (void *)&ssd1307fb_ssd1306_deviceinfo, 580 }, 581 { 582 .compatible = "solomon,ssd1307fb-i2c", 583 .data = (void *)&ssd1307fb_ssd1307_deviceinfo, 584 }, 585 { 586 .compatible = "solomon,ssd1309fb-i2c", 587 .data = (void *)&ssd1307fb_ssd1309_deviceinfo, 588 }, 589 {}, 590 }; 591 MODULE_DEVICE_TABLE(of, ssd1307fb_of_match); 592 593 static int ssd1307fb_probe(struct i2c_client *client) 594 { 595 struct device *dev = &client->dev; 596 struct backlight_device *bl; 597 char bl_name[12]; 598 struct fb_info *info; 599 struct fb_deferred_io *ssd1307fb_defio; 600 u32 vmem_size; 601 struct ssd1307fb_par *par; 602 void *vmem; 603 int ret; 604 605 info = framebuffer_alloc(sizeof(struct ssd1307fb_par), dev); 606 if (!info) 607 return -ENOMEM; 608 609 par = info->par; 610 par->info = info; 611 par->client = client; 612 613 par->device_info = device_get_match_data(dev); 614 615 par->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW); 616 if (IS_ERR(par->reset)) { 617 ret = dev_err_probe(dev, PTR_ERR(par->reset), 618 "failed to get reset gpio\n"); 619 goto fb_alloc_error; 620 } 621 622 par->vbat_reg = devm_regulator_get_optional(dev, "vbat"); 623 if (IS_ERR(par->vbat_reg)) { 624 ret = PTR_ERR(par->vbat_reg); 625 if (ret == -ENODEV) { 626 par->vbat_reg = NULL; 627 } else { 628 dev_err_probe(dev, ret, "failed to get VBAT regulator\n"); 629 goto fb_alloc_error; 630 } 631 } 632 633 if (device_property_read_u32(dev, "solomon,width", &par->width)) 634 par->width = 96; 635 636 if (device_property_read_u32(dev, "solomon,height", &par->height)) 637 par->height = 16; 638 639 if (device_property_read_u32(dev, "solomon,page-offset", &par->page_offset)) 640 par->page_offset = 1; 641 642 if (device_property_read_u32(dev, "solomon,col-offset", &par->col_offset)) 643 par->col_offset = 0; 644 645 if (device_property_read_u32(dev, "solomon,com-offset", &par->com_offset)) 646 par->com_offset = 0; 647 648 if (device_property_read_u32(dev, "solomon,prechargep1", &par->prechargep1)) 649 par->prechargep1 = 2; 650 651 if (device_property_read_u32(dev, "solomon,prechargep2", &par->prechargep2)) 652 par->prechargep2 = 2; 653 654 if (!device_property_read_u8_array(dev, "solomon,lookup-table", 655 par->lookup_table, 656 ARRAY_SIZE(par->lookup_table))) 657 par->lookup_table_set = 1; 658 659 par->seg_remap = !device_property_read_bool(dev, "solomon,segment-no-remap"); 660 par->com_seq = device_property_read_bool(dev, "solomon,com-seq"); 661 par->com_lrremap = device_property_read_bool(dev, "solomon,com-lrremap"); 662 par->com_invdir = device_property_read_bool(dev, "solomon,com-invdir"); 663 par->area_color_enable = 664 device_property_read_bool(dev, "solomon,area-color-enable"); 665 par->low_power = device_property_read_bool(dev, "solomon,low-power"); 666 667 par->contrast = 127; 668 par->vcomh = par->device_info->default_vcomh; 669 670 /* Setup display timing */ 671 if (device_property_read_u32(dev, "solomon,dclk-div", &par->dclk_div)) 672 par->dclk_div = par->device_info->default_dclk_div; 673 if (device_property_read_u32(dev, "solomon,dclk-frq", &par->dclk_frq)) 674 par->dclk_frq = par->device_info->default_dclk_frq; 675 676 vmem_size = DIV_ROUND_UP(par->width, 8) * par->height; 677 678 vmem = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 679 get_order(vmem_size)); 680 if (!vmem) { 681 dev_err(dev, "Couldn't allocate graphical memory.\n"); 682 ret = -ENOMEM; 683 goto fb_alloc_error; 684 } 685 686 ssd1307fb_defio = devm_kzalloc(dev, sizeof(*ssd1307fb_defio), 687 GFP_KERNEL); 688 if (!ssd1307fb_defio) { 689 dev_err(dev, "Couldn't allocate deferred io.\n"); 690 ret = -ENOMEM; 691 goto fb_alloc_error; 692 } 693 694 ssd1307fb_defio->delay = HZ / refreshrate; 695 ssd1307fb_defio->deferred_io = ssd1307fb_deferred_io; 696 697 info->fbops = &ssd1307fb_ops; 698 info->fix = ssd1307fb_fix; 699 info->fix.line_length = DIV_ROUND_UP(par->width, 8); 700 info->fbdefio = ssd1307fb_defio; 701 702 info->var = ssd1307fb_var; 703 info->var.xres = par->width; 704 info->var.xres_virtual = par->width; 705 info->var.yres = par->height; 706 info->var.yres_virtual = par->height; 707 708 info->screen_buffer = vmem; 709 info->fix.smem_start = __pa(vmem); 710 info->fix.smem_len = vmem_size; 711 712 fb_deferred_io_init(info); 713 714 i2c_set_clientdata(client, info); 715 716 if (par->reset) { 717 /* Reset the screen */ 718 gpiod_set_value_cansleep(par->reset, 1); 719 udelay(4); 720 gpiod_set_value_cansleep(par->reset, 0); 721 udelay(4); 722 } 723 724 if (par->vbat_reg) { 725 ret = regulator_enable(par->vbat_reg); 726 if (ret) { 727 dev_err(dev, "failed to enable VBAT: %d\n", ret); 728 goto reset_oled_error; 729 } 730 } 731 732 ret = ssd1307fb_init(par); 733 if (ret) 734 goto regulator_enable_error; 735 736 ret = register_framebuffer(info); 737 if (ret) { 738 dev_err(dev, "Couldn't register the framebuffer\n"); 739 goto panel_init_error; 740 } 741 742 snprintf(bl_name, sizeof(bl_name), "ssd1307fb%d", info->node); 743 bl = backlight_device_register(bl_name, dev, par, &ssd1307fb_bl_ops, 744 NULL); 745 if (IS_ERR(bl)) { 746 ret = PTR_ERR(bl); 747 dev_err(dev, "unable to register backlight device: %d\n", ret); 748 goto bl_init_error; 749 } 750 751 bl->props.brightness = par->contrast; 752 bl->props.max_brightness = MAX_CONTRAST; 753 info->bl_dev = bl; 754 755 dev_info(dev, "fb%d: %s framebuffer device registered, using %d bytes of video memory\n", info->node, info->fix.id, vmem_size); 756 757 return 0; 758 759 bl_init_error: 760 unregister_framebuffer(info); 761 panel_init_error: 762 pwm_disable(par->pwm); 763 pwm_put(par->pwm); 764 regulator_enable_error: 765 if (par->vbat_reg) 766 regulator_disable(par->vbat_reg); 767 reset_oled_error: 768 fb_deferred_io_cleanup(info); 769 fb_alloc_error: 770 framebuffer_release(info); 771 return ret; 772 } 773 774 static void ssd1307fb_remove(struct i2c_client *client) 775 { 776 struct fb_info *info = i2c_get_clientdata(client); 777 struct ssd1307fb_par *par = info->par; 778 779 ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_OFF); 780 781 backlight_device_unregister(info->bl_dev); 782 783 unregister_framebuffer(info); 784 pwm_disable(par->pwm); 785 pwm_put(par->pwm); 786 if (par->vbat_reg) 787 regulator_disable(par->vbat_reg); 788 fb_deferred_io_cleanup(info); 789 __free_pages(__va(info->fix.smem_start), get_order(info->fix.smem_len)); 790 framebuffer_release(info); 791 } 792 793 static const struct i2c_device_id ssd1307fb_i2c_id[] = { 794 { "ssd1305fb", 0 }, 795 { "ssd1306fb", 0 }, 796 { "ssd1307fb", 0 }, 797 { "ssd1309fb", 0 }, 798 { } 799 }; 800 MODULE_DEVICE_TABLE(i2c, ssd1307fb_i2c_id); 801 802 static struct i2c_driver ssd1307fb_driver = { 803 .probe = ssd1307fb_probe, 804 .remove = ssd1307fb_remove, 805 .id_table = ssd1307fb_i2c_id, 806 .driver = { 807 .name = "ssd1307fb", 808 .of_match_table = ssd1307fb_of_match, 809 }, 810 }; 811 812 module_i2c_driver(ssd1307fb_driver); 813 814 MODULE_DESCRIPTION("FB driver for the Solomon SSD1307 OLED controller"); 815 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>"); 816 MODULE_LICENSE("GPL"); 817