drivers/staging/fbtft/fbtft-core.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2013 Noralf Tronnes
   4  *
   5  * This driver is inspired by:
   6  *   st7735fb.c, Copyright (C) 2011, Matt Porter
   7  *   broadsheetfb.c, Copyright (C) 2008, Jaya Kumar
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/kernel.h>
  12 #include <linux/errno.h>
  13 #include <linux/string.h>
  14 #include <linux/mm.h>
  15 #include <linux/vmalloc.h>
  16 #include <linux/slab.h>
  17 #include <linux/init.h>
  18 #include <linux/fb.h>
  19 #include <linux/gpio/consumer.h>
  20 #include <linux/spi/spi.h>
  21 #include <linux/delay.h>
  22 #include <linux/uaccess.h>
  23 #include <linux/backlight.h>
  24 #include <linux/platform_device.h>
  25 #include <linux/property.h>
  26 #include <linux/spinlock.h>
  27
  28 #include <video/mipi_display.h>
  29
  30 #include "fbtft.h"
  31 #include "internal.h"
  32
  33 static unsigned long debug;
  34 module_param(debug, ulong, 0000);
  35 MODULE_PARM_DESC(debug, "override device debug level");
  36
  37 int fbtft_write_buf_dc(struct fbtft_par *par, void *buf, size_t len, int dc)
  38 {
  39         int ret;
  40
  41         gpiod_set_value(par->gpio.dc, dc);
  42
  43         ret = par->fbtftops.write(par, buf, len);
  44         if (ret < 0)
  45                 dev_err(par->info->device,
  46                         "write() failed and returned %d\n", ret);
  47         return ret;
  48 }
  49 EXPORT_SYMBOL(fbtft_write_buf_dc);
  50
  51 void fbtft_dbg_hex(const struct device *dev, int groupsize,
  52                    const void *buf, size_t len, const char *fmt, ...)
  53 {
  54         va_list args;
  55         static char textbuf[512];
  56         char *text = textbuf;
  57         size_t text_len;
  58
  59         va_start(args, fmt);
  60         text_len = vscnprintf(text, sizeof(textbuf), fmt, args);
  61         va_end(args);
  62
  63         hex_dump_to_buffer(buf, len, 32, groupsize, text + text_len,
  64                            512 - text_len, false);
  65
  66         if (len > 32)
  67                 dev_info(dev, "%s ...\n", text);
  68         else
  69                 dev_info(dev, "%s\n", text);
  70 }
  71 EXPORT_SYMBOL(fbtft_dbg_hex);
  72
  73 static int fbtft_request_one_gpio(struct fbtft_par *par,
  74                                   const char *name, int index,
  75                                   struct gpio_desc **gpiop)
  76 {
  77         struct device *dev = par->info->device;
  78
  79         *gpiop = devm_gpiod_get_index_optional(dev, name, index,
  80                                                GPIOD_OUT_LOW);
  81         if (IS_ERR(*gpiop))
  82                 return dev_err_probe(dev, PTR_ERR(*gpiop), "Failed to request %s GPIO\n", name);
  83
  84         fbtft_par_dbg(DEBUG_REQUEST_GPIOS, par, "%s: '%s' GPIO\n",
  85                       __func__, name);
  86
  87         return 0;
  88 }
  89
  90 static int fbtft_request_gpios(struct fbtft_par *par)
  91 {
  92         int i;
  93         int ret;
  94
  95         ret = fbtft_request_one_gpio(par, "reset", 0, &par->gpio.reset);
  96         if (ret)
  97                 return ret;
  98         ret = fbtft_request_one_gpio(par, "dc", 0, &par->gpio.dc);
  99         if (ret)
 100                 return ret;
 101         ret = fbtft_request_one_gpio(par, "rd", 0, &par->gpio.rd);
 102         if (ret)
 103                 return ret;
 104         ret = fbtft_request_one_gpio(par, "wr", 0, &par->gpio.wr);
 105         if (ret)
 106                 return ret;
 107         ret = fbtft_request_one_gpio(par, "cs", 0, &par->gpio.cs);
 108         if (ret)
 109                 return ret;
 110         ret = fbtft_request_one_gpio(par, "latch", 0, &par->gpio.latch);
 111         if (ret)
 112                 return ret;
 113         for (i = 0; i < 16; i++) {
 114                 ret = fbtft_request_one_gpio(par, "db", i,
 115                                              &par->gpio.db[i]);
 116                 if (ret)
 117                         return ret;
 118                 ret = fbtft_request_one_gpio(par, "led", i,
 119                                              &par->gpio.led[i]);
 120                 if (ret)
 121                         return ret;
 122                 ret = fbtft_request_one_gpio(par, "aux", i,
 123                                              &par->gpio.aux[i]);
 124                 if (ret)
 125                         return ret;
 126         }
 127
 128         return 0;
 129 }
 130
 131 static int fbtft_backlight_update_status(struct backlight_device *bd)
 132 {
 133         struct fbtft_par *par = bl_get_data(bd);
 134         bool polarity = par->polarity;
 135
 136         fbtft_par_dbg(DEBUG_BACKLIGHT, par,
 137                       "%s: polarity=%d, power=%d, fb_blank=%d\n",
 138                       __func__, polarity, bd->props.power, bd->props.fb_blank);
 139
 140         if (!backlight_is_blank(bd))
 141                 gpiod_set_value(par->gpio.led[0], polarity);
 142         else
 143                 gpiod_set_value(par->gpio.led[0], !polarity);
 144
 145         return 0;
 146 }
 147
 148 static int fbtft_backlight_get_brightness(struct backlight_device *bd)
 149 {
 150         return bd->props.brightness;
 151 }
 152
 153 void fbtft_unregister_backlight(struct fbtft_par *par)
 154 {
 155         if (par->info->bl_dev) {
 156                 par->info->bl_dev->props.power = FB_BLANK_POWERDOWN;
 157                 backlight_update_status(par->info->bl_dev);
 158                 backlight_device_unregister(par->info->bl_dev);
 159                 par->info->bl_dev = NULL;
 160         }
 161 }
 162 EXPORT_SYMBOL(fbtft_unregister_backlight);
 163
 164 static const struct backlight_ops fbtft_bl_ops = {
 165         .get_brightness = fbtft_backlight_get_brightness,
 166         .update_status  = fbtft_backlight_update_status,
 167 };
 168
 169 void fbtft_register_backlight(struct fbtft_par *par)
 170 {
 171         struct backlight_device *bd;
 172         struct backlight_properties bl_props = { 0, };
 173
 174         if (!par->gpio.led[0]) {
 175                 fbtft_par_dbg(DEBUG_BACKLIGHT, par,
 176                               "%s(): led pin not set, exiting.\n", __func__);
 177                 return;
 178         }
 179
 180         bl_props.type = BACKLIGHT_RAW;
 181         /* Assume backlight is off, get polarity from current state of pin */
 182         bl_props.power = FB_BLANK_POWERDOWN;
 183         if (!gpiod_get_value(par->gpio.led[0]))
 184                 par->polarity = true;
 185
 186         bd = backlight_device_register(dev_driver_string(par->info->device),
 187                                        par->info->device, par,
 188                                        &fbtft_bl_ops, &bl_props);
 189         if (IS_ERR(bd)) {
 190                 dev_err(par->info->device,
 191                         "cannot register backlight device (%ld)\n",
 192                         PTR_ERR(bd));
 193                 return;
 194         }
 195         par->info->bl_dev = bd;
 196
 197         if (!par->fbtftops.unregister_backlight)
 198                 par->fbtftops.unregister_backlight = fbtft_unregister_backlight;
 199 }
 200 EXPORT_SYMBOL(fbtft_register_backlight);
 201
 202 static void fbtft_set_addr_win(struct fbtft_par *par, int xs, int ys, int xe,
 203                                int ye)
 204 {
 205         write_reg(par, MIPI_DCS_SET_COLUMN_ADDRESS,
 206                   (xs >> 8) & 0xFF, xs & 0xFF, (xe >> 8) & 0xFF, xe & 0xFF);
 207
 208         write_reg(par, MIPI_DCS_SET_PAGE_ADDRESS,
 209                   (ys >> 8) & 0xFF, ys & 0xFF, (ye >> 8) & 0xFF, ye & 0xFF);
 210
 211         write_reg(par, MIPI_DCS_WRITE_MEMORY_START);
 212 }
 213
 214 static void fbtft_reset(struct fbtft_par *par)
 215 {
 216         if (!par->gpio.reset)
 217                 return;
 218
 219         fbtft_par_dbg(DEBUG_RESET, par, "%s()\n", __func__);
 220
 221         gpiod_set_value_cansleep(par->gpio.reset, 1);
 222         usleep_range(20, 40);
 223         gpiod_set_value_cansleep(par->gpio.reset, 0);
 224         msleep(120);
 225
 226         gpiod_set_value_cansleep(par->gpio.cs, 1);  /* Activate chip */
 227 }
 228
 229 static void fbtft_update_display(struct fbtft_par *par, unsigned int start_line,
 230                                  unsigned int end_line)
 231 {
 232         size_t offset, len;
 233         ktime_t ts_start, ts_end;
 234         long fps, throughput;
 235         bool timeit = false;
 236         int ret = 0;
 237
 238         if (unlikely(par->debug & (DEBUG_TIME_FIRST_UPDATE |
 239                         DEBUG_TIME_EACH_UPDATE))) {
 240                 if ((par->debug & DEBUG_TIME_EACH_UPDATE) ||
 241                     ((par->debug & DEBUG_TIME_FIRST_UPDATE) &&
 242                     !par->first_update_done)) {
 243                         ts_start = ktime_get();
 244                         timeit = true;
 245                 }
 246         }
 247
 248         /* Sanity checks */
 249         if (start_line > end_line) {
 250                 dev_warn(par->info->device,
 251                          "%s: start_line=%u is larger than end_line=%u. Shouldn't happen, will do full display update\n",
 252                          __func__, start_line, end_line);
 253                 start_line = 0;
 254                 end_line = par->info->var.yres - 1;
 255         }
 256         if (start_line > par->info->var.yres - 1 ||
 257             end_line > par->info->var.yres - 1) {
 258                 dev_warn(par->info->device,
 259                          "%s: start_line=%u or end_line=%u is larger than max=%d. Shouldn't happen, will do full display update\n",
 260                          __func__, start_line,
 261                          end_line, par->info->var.yres - 1);
 262                 start_line = 0;
 263                 end_line = par->info->var.yres - 1;
 264         }
 265
 266         fbtft_par_dbg(DEBUG_UPDATE_DISPLAY, par, "%s(start_line=%u, end_line=%u)\n",
 267                       __func__, start_line, end_line);
 268
 269         if (par->fbtftops.set_addr_win)
 270                 par->fbtftops.set_addr_win(par, 0, start_line,
 271                                 par->info->var.xres - 1, end_line);
 272
 273         offset = start_line * par->info->fix.line_length;
 274         len = (end_line - start_line + 1) * par->info->fix.line_length;
 275         ret = par->fbtftops.write_vmem(par, offset, len);
 276         if (ret < 0)
 277                 dev_err(par->info->device,
 278                         "%s: write_vmem failed to update display buffer\n",
 279                         __func__);
 280
 281         if (unlikely(timeit)) {
 282                 ts_end = ktime_get();
 283                 if (!ktime_to_ns(par->update_time))
 284                         par->update_time = ts_start;
 285
 286                 fps = ktime_us_delta(ts_start, par->update_time);
 287                 par->update_time = ts_start;
 288                 fps = fps ? 1000000 / fps : 0;
 289
 290                 throughput = ktime_us_delta(ts_end, ts_start);
 291                 throughput = throughput ? (len * 1000) / throughput : 0;
 292                 throughput = throughput * 1000 / 1024;
 293
 294                 dev_info(par->info->device,
 295                          "Display update: %ld kB/s, fps=%ld\n",
 296                          throughput, fps);
 297                 par->first_update_done = true;
 298         }
 299 }
 300
 301 static void fbtft_mkdirty(struct fb_info *info, int y, int height)
 302 {
 303         struct fbtft_par *par = info->par;
 304         struct fb_deferred_io *fbdefio = info->fbdefio;
 305
 306         /* special case, needed ? */
 307         if (y == -1) {
 308                 y = 0;
 309                 height = info->var.yres;
 310         }
 311
 312         /* Mark display lines/area as dirty */
 313         spin_lock(&par->dirty_lock);
 314         if (y < par->dirty_lines_start)
 315                 par->dirty_lines_start = y;
 316         if (y + height - 1 > par->dirty_lines_end)
 317                 par->dirty_lines_end = y + height - 1;
 318         spin_unlock(&par->dirty_lock);
 319
 320         /* Schedule deferred_io to update display (no-op if already on queue)*/
 321         schedule_delayed_work(&info->deferred_work, fbdefio->delay);
 322 }
 323
 324 static void fbtft_deferred_io(struct fb_info *info, struct list_head *pagereflist)
 325 {
 326         struct fbtft_par *par = info->par;
 327         unsigned int dirty_lines_start, dirty_lines_end;
 328         struct fb_deferred_io_pageref *pageref;
 329         unsigned int y_low = 0, y_high = 0;
 330         int count = 0;
 331
 332         spin_lock(&par->dirty_lock);
 333         dirty_lines_start = par->dirty_lines_start;
 334         dirty_lines_end = par->dirty_lines_end;
 335         /* set display line markers as clean */
 336         par->dirty_lines_start = par->info->var.yres - 1;
 337         par->dirty_lines_end = 0;
 338         spin_unlock(&par->dirty_lock);
 339
 340         /* Mark display lines as dirty */
 341         list_for_each_entry(pageref, pagereflist, list) {
 342                 count++;
 343                 y_low = pageref->offset / info->fix.line_length;
 344                 y_high = (pageref->offset + PAGE_SIZE - 1) / info->fix.line_length;
 345                 dev_dbg(info->device,
 346                         "page->index=%lu y_low=%d y_high=%d\n",
 347                         pageref->page->index, y_low, y_high);
 348                 if (y_high > info->var.yres - 1)
 349                         y_high = info->var.yres - 1;
 350                 if (y_low < dirty_lines_start)
 351                         dirty_lines_start = y_low;
 352                 if (y_high > dirty_lines_end)
 353                         dirty_lines_end = y_high;
 354         }
 355
 356         par->fbtftops.update_display(info->par,
 357                                         dirty_lines_start, dirty_lines_end);
 358 }
 359
 360 static void fbtft_fb_fillrect(struct fb_info *info,
 361                               const struct fb_fillrect *rect)
 362 {
 363         struct fbtft_par *par = info->par;
 364
 365         dev_dbg(info->dev,
 366                 "%s: dx=%d, dy=%d, width=%d, height=%d\n",
 367                 __func__, rect->dx, rect->dy, rect->width, rect->height);
 368         sys_fillrect(info, rect);
 369
 370         par->fbtftops.mkdirty(info, rect->dy, rect->height);
 371 }
 372
 373 static void fbtft_fb_copyarea(struct fb_info *info,
 374                               const struct fb_copyarea *area)
 375 {
 376         struct fbtft_par *par = info->par;
 377
 378         dev_dbg(info->dev,
 379                 "%s: dx=%d, dy=%d, width=%d, height=%d\n",
 380                 __func__,  area->dx, area->dy, area->width, area->height);
 381         sys_copyarea(info, area);
 382
 383         par->fbtftops.mkdirty(info, area->dy, area->height);
 384 }
 385
 386 static void fbtft_fb_imageblit(struct fb_info *info,
 387                                const struct fb_image *image)
 388 {
 389         struct fbtft_par *par = info->par;
 390
 391         dev_dbg(info->dev,
 392                 "%s: dx=%d, dy=%d, width=%d, height=%d\n",
 393                 __func__,  image->dx, image->dy, image->width, image->height);
 394         sys_imageblit(info, image);
 395
 396         par->fbtftops.mkdirty(info, image->dy, image->height);
 397 }
 398
 399 static ssize_t fbtft_fb_write(struct fb_info *info, const char __user *buf,
 400                               size_t count, loff_t *ppos)
 401 {
 402         struct fbtft_par *par = info->par;
 403         ssize_t res;
 404
 405         dev_dbg(info->dev,
 406                 "%s: count=%zd, ppos=%llu\n", __func__,  count, *ppos);
 407         res = fb_sys_write(info, buf, count, ppos);
 408
 409         /* TODO: only mark changed area update all for now */
 410         par->fbtftops.mkdirty(info, -1, 0);
 411
 412         return res;
 413 }
 414
 415 /* from pxafb.c */
 416 static unsigned int chan_to_field(unsigned int chan, struct fb_bitfield *bf)
 417 {
 418         chan &= 0xffff;
 419         chan >>= 16 - bf->length;
 420         return chan << bf->offset;
 421 }
 422
 423 static int fbtft_fb_setcolreg(unsigned int regno, unsigned int red,
 424                               unsigned int green, unsigned int blue,
 425                               unsigned int transp, struct fb_info *info)
 426 {
 427         unsigned int val;
 428         int ret = 1;
 429
 430         dev_dbg(info->dev,
 431                 "%s(regno=%u, red=0x%X, green=0x%X, blue=0x%X, trans=0x%X)\n",
 432                 __func__, regno, red, green, blue, transp);
 433
 434         switch (info->fix.visual) {
 435         case FB_VISUAL_TRUECOLOR:
 436                 if (regno < 16) {
 437                         u32 *pal = info->pseudo_palette;
 438
 439                         val  = chan_to_field(red,   &info->var.red);
 440                         val |= chan_to_field(green, &info->var.green);
 441                         val |= chan_to_field(blue,  &info->var.blue);
 442
 443                         pal[regno] = val;
 444                         ret = 0;
 445                 }
 446                 break;
 447         }
 448         return ret;
 449 }
 450
 451 static int fbtft_fb_blank(int blank, struct fb_info *info)
 452 {
 453         struct fbtft_par *par = info->par;
 454         int ret = -EINVAL;
 455
 456         dev_dbg(info->dev, "%s(blank=%d)\n",
 457                 __func__, blank);
 458
 459         if (!par->fbtftops.blank)
 460                 return ret;
 461
 462         switch (blank) {
 463         case FB_BLANK_POWERDOWN:
 464         case FB_BLANK_VSYNC_SUSPEND:
 465         case FB_BLANK_HSYNC_SUSPEND:
 466         case FB_BLANK_NORMAL:
 467                 ret = par->fbtftops.blank(par, true);
 468                 break;
 469         case FB_BLANK_UNBLANK:
 470                 ret = par->fbtftops.blank(par, false);
 471                 break;
 472         }
 473         return ret;
 474 }
 475
 476 static void fbtft_merge_fbtftops(struct fbtft_ops *dst, struct fbtft_ops *src)
 477 {
 478         if (src->write)
 479                 dst->write = src->write;
 480         if (src->read)
 481                 dst->read = src->read;
 482         if (src->write_vmem)
 483                 dst->write_vmem = src->write_vmem;
 484         if (src->write_register)
 485                 dst->write_register = src->write_register;
 486         if (src->set_addr_win)
 487                 dst->set_addr_win = src->set_addr_win;
 488         if (src->reset)
 489                 dst->reset = src->reset;
 490         if (src->mkdirty)
 491                 dst->mkdirty = src->mkdirty;
 492         if (src->update_display)
 493                 dst->update_display = src->update_display;
 494         if (src->init_display)
 495                 dst->init_display = src->init_display;
 496         if (src->blank)
 497                 dst->blank = src->blank;
 498         if (src->request_gpios_match)
 499                 dst->request_gpios_match = src->request_gpios_match;
 500         if (src->request_gpios)
 501                 dst->request_gpios = src->request_gpios;
 502         if (src->verify_gpios)
 503                 dst->verify_gpios = src->verify_gpios;
 504         if (src->register_backlight)
 505                 dst->register_backlight = src->register_backlight;
 506         if (src->unregister_backlight)
 507                 dst->unregister_backlight = src->unregister_backlight;
 508         if (src->set_var)
 509                 dst->set_var = src->set_var;
 510         if (src->set_gamma)
 511                 dst->set_gamma = src->set_gamma;
 512 }
 513
 514 /**
 515  * fbtft_framebuffer_alloc - creates a new frame buffer info structure
 516  *
 517  * @display: pointer to structure describing the display
 518  * @dev: pointer to the device for this fb, this can be NULL
 519  * @pdata: platform data for the display in use
 520  *
 521  * Creates a new frame buffer info structure.
 522  *
 523  * Also creates and populates the following structures:
 524  *   info->fbops
 525  *   info->fbdefio
 526  *   info->pseudo_palette
 527  *   par->fbtftops
 528  *   par->txbuf
 529  *
 530  * Returns the new structure, or NULL if an error occurred.
 531  *
 532  */
 533 struct fb_info *fbtft_framebuffer_alloc(struct fbtft_display *display,
 534                                         struct device *dev,
 535                                         struct fbtft_platform_data *pdata)
 536 {
 537         struct fb_info *info;
 538         struct fbtft_par *par;
 539         struct fb_ops *fbops = NULL;
 540         struct fb_deferred_io *fbdefio = NULL;
 541         u8 *vmem = NULL;
 542         void *txbuf = NULL;
 543         void *buf = NULL;
 544         unsigned int width;
 545         unsigned int height;
 546         int txbuflen = display->txbuflen;
 547         unsigned int bpp = display->bpp;
 548         unsigned int fps = display->fps;
 549         int vmem_size;
 550         const s16 *init_sequence = display->init_sequence;
 551         char *gamma = display->gamma;
 552         u32 *gamma_curves = NULL;
 553
 554         /* sanity check */
 555         if (display->gamma_num * display->gamma_len >
 556                         FBTFT_GAMMA_MAX_VALUES_TOTAL) {
 557                 dev_err(dev, "FBTFT_GAMMA_MAX_VALUES_TOTAL=%d is exceeded\n",
 558                         FBTFT_GAMMA_MAX_VALUES_TOTAL);
 559                 return NULL;
 560         }
 561
 562         /* defaults */
 563         if (!fps)
 564                 fps = 20;
 565         if (!bpp)
 566                 bpp = 16;
 567
 568         if (!pdata) {
 569                 dev_err(dev, "platform data is missing\n");
 570                 return NULL;
 571         }
 572
 573         /* override driver values? */
 574         if (pdata->fps)
 575                 fps = pdata->fps;
 576         if (pdata->txbuflen)
 577                 txbuflen = pdata->txbuflen;
 578         if (pdata->display.init_sequence)
 579                 init_sequence = pdata->display.init_sequence;
 580         if (pdata->gamma)
 581                 gamma = pdata->gamma;
 582         if (pdata->display.debug)
 583                 display->debug = pdata->display.debug;
 584         if (pdata->display.backlight)
 585                 display->backlight = pdata->display.backlight;
 586         if (pdata->display.width)
 587                 display->width = pdata->display.width;
 588         if (pdata->display.height)
 589                 display->height = pdata->display.height;
 590         if (pdata->display.buswidth)
 591                 display->buswidth = pdata->display.buswidth;
 592         if (pdata->display.regwidth)
 593                 display->regwidth = pdata->display.regwidth;
 594
 595         display->debug |= debug;
 596         fbtft_expand_debug_value(&display->debug);
 597
 598         switch (pdata->rotate) {
 599         case 90:
 600         case 270:
 601                 width =  display->height;
 602                 height = display->width;
 603                 break;
 604         default:
 605                 width =  display->width;
 606                 height = display->height;
 607         }
 608
 609         vmem_size = display->width * display->height * bpp / 8;
 610         vmem = vzalloc(vmem_size);
 611         if (!vmem)
 612                 goto alloc_fail;
 613
 614         fbops = devm_kzalloc(dev, sizeof(struct fb_ops), GFP_KERNEL);
 615         if (!fbops)
 616                 goto alloc_fail;
 617
 618         fbdefio = devm_kzalloc(dev, sizeof(struct fb_deferred_io), GFP_KERNEL);
 619         if (!fbdefio)
 620                 goto alloc_fail;
 621
 622         buf = devm_kzalloc(dev, 128, GFP_KERNEL);
 623         if (!buf)
 624                 goto alloc_fail;
 625
 626         if (display->gamma_num && display->gamma_len) {
 627                 gamma_curves = devm_kcalloc(dev,
 628                                             display->gamma_num *
 629                                             display->gamma_len,
 630                                             sizeof(gamma_curves[0]),
 631                                             GFP_KERNEL);
 632                 if (!gamma_curves)
 633                         goto alloc_fail;
 634         }
 635
 636         info = framebuffer_alloc(sizeof(struct fbtft_par), dev);
 637         if (!info)
 638                 goto alloc_fail;
 639
 640         info->screen_buffer = vmem;
 641         info->fbops = fbops;
 642         info->fbdefio = fbdefio;
 643
 644         fbops->owner        =      dev->driver->owner;
 645         fbops->fb_read      =      fb_sys_read;
 646         fbops->fb_write     =      fbtft_fb_write;
 647         fbops->fb_fillrect  =      fbtft_fb_fillrect;
 648         fbops->fb_copyarea  =      fbtft_fb_copyarea;
 649         fbops->fb_imageblit =      fbtft_fb_imageblit;
 650         fbops->fb_setcolreg =      fbtft_fb_setcolreg;
 651         fbops->fb_blank     =      fbtft_fb_blank;
 652         fbops->fb_mmap      =      fb_deferred_io_mmap;
 653
 654         fbdefio->delay =            HZ / fps;
 655         fbdefio->sort_pagereflist = true;
 656         fbdefio->deferred_io =      fbtft_deferred_io;
 657
 658         snprintf(info->fix.id, sizeof(info->fix.id), "%s", dev->driver->name);
 659         info->fix.type =           FB_TYPE_PACKED_PIXELS;
 660         info->fix.visual =         FB_VISUAL_TRUECOLOR;
 661         info->fix.xpanstep =       0;
 662         info->fix.ypanstep =       0;
 663         info->fix.ywrapstep =      0;
 664         info->fix.line_length =    width * bpp / 8;
 665         info->fix.accel =          FB_ACCEL_NONE;
 666         info->fix.smem_len =       vmem_size;
 667         fb_deferred_io_init(info);
 668
 669         info->var.rotate =         pdata->rotate;
 670         info->var.xres =           width;
 671         info->var.yres =           height;
 672         info->var.xres_virtual =   info->var.xres;
 673         info->var.yres_virtual =   info->var.yres;
 674         info->var.bits_per_pixel = bpp;
 675         info->var.nonstd =         1;
 676
 677         /* RGB565 */
 678         info->var.red.offset =     11;
 679         info->var.red.length =     5;
 680         info->var.green.offset =   5;
 681         info->var.green.length =   6;
 682         info->var.blue.offset =    0;
 683         info->var.blue.length =    5;
 684         info->var.transp.offset =  0;
 685         info->var.transp.length =  0;
 686
 687         info->flags =              FBINFO_VIRTFB;
 688
 689         par = info->par;
 690         par->info = info;
 691         par->pdata = pdata;
 692         par->debug = display->debug;
 693         par->buf = buf;
 694         spin_lock_init(&par->dirty_lock);
 695         par->bgr = pdata->bgr;
 696         par->startbyte = pdata->startbyte;
 697         par->init_sequence = init_sequence;
 698         par->gamma.curves = gamma_curves;
 699         par->gamma.num_curves = display->gamma_num;
 700         par->gamma.num_values = display->gamma_len;
 701         mutex_init(&par->gamma.lock);
 702         info->pseudo_palette = par->pseudo_palette;
 703
 704         if (par->gamma.curves && gamma) {
 705                 if (fbtft_gamma_parse_str(par, par->gamma.curves, gamma,
 706                                           strlen(gamma)))
 707                         goto release_framebuf;
 708         }
 709
 710         /* Transmit buffer */
 711         if (txbuflen == -1)
 712                 txbuflen = vmem_size + 2; /* add in case startbyte is used */
 713         if (txbuflen >= vmem_size + 2)
 714                 txbuflen = 0;
 715
 716 #ifdef __LITTLE_ENDIAN
 717         if ((!txbuflen) && (bpp > 8))
 718                 txbuflen = PAGE_SIZE; /* need buffer for byteswapping */
 719 #endif
 720
 721         if (txbuflen > 0) {
 722                 txbuf = devm_kzalloc(par->info->device, txbuflen, GFP_KERNEL);
 723                 if (!txbuf)
 724                         goto release_framebuf;
 725                 par->txbuf.buf = txbuf;
 726                 par->txbuf.len = txbuflen;
 727         }
 728
 729         /* default fbtft operations */
 730         par->fbtftops.write = fbtft_write_spi;
 731         par->fbtftops.read = fbtft_read_spi;
 732         par->fbtftops.write_vmem = fbtft_write_vmem16_bus8;
 733         par->fbtftops.write_register = fbtft_write_reg8_bus8;
 734         par->fbtftops.set_addr_win = fbtft_set_addr_win;
 735         par->fbtftops.reset = fbtft_reset;
 736         par->fbtftops.mkdirty = fbtft_mkdirty;
 737         par->fbtftops.update_display = fbtft_update_display;
 738         if (display->backlight)
 739                 par->fbtftops.register_backlight = fbtft_register_backlight;
 740
 741         /* use driver provided functions */
 742         fbtft_merge_fbtftops(&par->fbtftops, &display->fbtftops);
 743
 744         return info;
 745
 746 release_framebuf:
 747         framebuffer_release(info);
 748
 749 alloc_fail:
 750         vfree(vmem);
 751
 752         return NULL;
 753 }
 754 EXPORT_SYMBOL(fbtft_framebuffer_alloc);
 755
 756 /**
 757  * fbtft_framebuffer_release - frees up all memory used by the framebuffer
 758  *
 759  * @info: frame buffer info structure
 760  *
 761  */
 762 void fbtft_framebuffer_release(struct fb_info *info)
 763 {
 764         fb_deferred_io_cleanup(info);
 765         vfree(info->screen_buffer);
 766         framebuffer_release(info);
 767 }
 768 EXPORT_SYMBOL(fbtft_framebuffer_release);
 769
 770 /**
 771  *      fbtft_register_framebuffer - registers a tft frame buffer device
 772  *      @fb_info: frame buffer info structure
 773  *
 774  *  Sets SPI driverdata if needed
 775  *  Requests needed gpios.
 776  *  Initializes display
 777  *  Updates display.
 778  *      Registers a frame buffer device @fb_info.
 779  *
 780  *      Returns negative errno on error, or zero for success.
 781  *
 782  */
 783 int fbtft_register_framebuffer(struct fb_info *fb_info)
 784 {
 785         int ret;
 786         char text1[50] = "";
 787         char text2[50] = "";
 788         struct fbtft_par *par = fb_info->par;
 789         struct spi_device *spi = par->spi;
 790
 791         /* sanity checks */
 792         if (!par->fbtftops.init_display) {
 793                 dev_err(fb_info->device, "missing fbtftops.init_display()\n");
 794                 return -EINVAL;
 795         }
 796
 797         if (spi)
 798                 spi_set_drvdata(spi, fb_info);
 799         if (par->pdev)
 800                 platform_set_drvdata(par->pdev, fb_info);
 801
 802         ret = par->fbtftops.request_gpios(par);
 803         if (ret < 0)
 804                 goto reg_fail;
 805
 806         if (par->fbtftops.verify_gpios) {
 807                 ret = par->fbtftops.verify_gpios(par);
 808                 if (ret < 0)
 809                         goto reg_fail;
 810         }
 811
 812         ret = par->fbtftops.init_display(par);
 813         if (ret < 0)
 814                 goto reg_fail;
 815         if (par->fbtftops.set_var) {
 816                 ret = par->fbtftops.set_var(par);
 817                 if (ret < 0)
 818                         goto reg_fail;
 819         }
 820
 821         /* update the entire display */
 822         par->fbtftops.update_display(par, 0, par->info->var.yres - 1);
 823
 824         if (par->fbtftops.set_gamma && par->gamma.curves) {
 825                 ret = par->fbtftops.set_gamma(par, par->gamma.curves);
 826                 if (ret)
 827                         goto reg_fail;
 828         }
 829
 830         if (par->fbtftops.register_backlight)
 831                 par->fbtftops.register_backlight(par);
 832
 833         ret = register_framebuffer(fb_info);
 834         if (ret < 0)
 835                 goto reg_fail;
 836
 837         fbtft_sysfs_init(par);
 838
 839         if (par->txbuf.buf && par->txbuf.len >= 1024)
 840                 sprintf(text1, ", %zu KiB buffer memory", par->txbuf.len >> 10);
 841         if (spi)
 842                 sprintf(text2, ", spi%d.%d at %d MHz", spi->master->bus_num,
 843                         spi_get_chipselect(spi, 0), spi->max_speed_hz / 1000000);
 844         dev_info(fb_info->dev,
 845                  "%s frame buffer, %dx%d, %d KiB video memory%s, fps=%lu%s\n",
 846                  fb_info->fix.id, fb_info->var.xres, fb_info->var.yres,
 847                  fb_info->fix.smem_len >> 10, text1,
 848                  HZ / fb_info->fbdefio->delay, text2);
 849
 850         /* Turn on backlight if available */
 851         if (fb_info->bl_dev) {
 852                 fb_info->bl_dev->props.power = FB_BLANK_UNBLANK;
 853                 fb_info->bl_dev->ops->update_status(fb_info->bl_dev);
 854         }
 855
 856         return 0;
 857
 858 reg_fail:
 859         if (par->fbtftops.unregister_backlight)
 860                 par->fbtftops.unregister_backlight(par);
 861
 862         return ret;
 863 }
 864 EXPORT_SYMBOL(fbtft_register_framebuffer);
 865
 866 /**
 867  *      fbtft_unregister_framebuffer - releases a tft frame buffer device
 868  *      @fb_info: frame buffer info structure
 869  *
 870  *  Frees SPI driverdata if needed
 871  *  Frees gpios.
 872  *      Unregisters frame buffer device.
 873  *
 874  */
 875 int fbtft_unregister_framebuffer(struct fb_info *fb_info)
 876 {
 877         struct fbtft_par *par = fb_info->par;
 878
 879         if (par->fbtftops.unregister_backlight)
 880                 par->fbtftops.unregister_backlight(par);
 881         fbtft_sysfs_exit(par);
 882         unregister_framebuffer(fb_info);
 883
 884         return 0;
 885 }
 886 EXPORT_SYMBOL(fbtft_unregister_framebuffer);
 887
 888 /**
 889  * fbtft_init_display_from_property() - Device Tree init_display() function
 890  * @par: Driver data
 891  *
 892  * Return: 0 if successful, negative if error
 893  */
 894 static int fbtft_init_display_from_property(struct fbtft_par *par)
 895 {
 896         struct device *dev = par->info->device;
 897         int buf[64], count, index, i, j, ret;
 898         u32 *values;
 899         u32 val;
 900
 901         count = device_property_count_u32(dev, "init");
 902         if (count < 0)
 903                 return count;
 904         if (count == 0)
 905                 return -EINVAL;
 906
 907         values = kmalloc_array(count + 1, sizeof(*values), GFP_KERNEL);
 908         if (!values)
 909                 return -ENOMEM;
 910
 911         ret = device_property_read_u32_array(dev, "init", values, count);
 912         if (ret)
 913                 goto out_free;
 914
 915         par->fbtftops.reset(par);
 916
 917         index = -1;
 918         val = values[++index];
 919
 920         while (index < count) {
 921                 if (val & FBTFT_OF_INIT_CMD) {
 922                         val &= 0xFFFF;
 923                         i = 0;
 924                         while ((index < count) && !(val & 0xFFFF0000)) {
 925                                 if (i > 63) {
 926                                         dev_err(dev,
 927                                                 "%s: Maximum register values exceeded\n",
 928                                                 __func__);
 929                                         ret = -EINVAL;
 930                                         goto out_free;
 931                                 }
 932                                 buf[i++] = val;
 933                                 val = values[++index];
 934                         }
 935                         /* make debug message */
 936                         fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
 937                                       "init: write_register:\n");
 938                         for (j = 0; j < i; j++)
 939                                 fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
 940                                               "buf[%d] = %02X\n", j, buf[j]);
 941
 942                         par->fbtftops.write_register(par, i,
 943                                 buf[0], buf[1], buf[2], buf[3],
 944                                 buf[4], buf[5], buf[6], buf[7],
 945                                 buf[8], buf[9], buf[10], buf[11],
 946                                 buf[12], buf[13], buf[14], buf[15],
 947                                 buf[16], buf[17], buf[18], buf[19],
 948                                 buf[20], buf[21], buf[22], buf[23],
 949                                 buf[24], buf[25], buf[26], buf[27],
 950                                 buf[28], buf[29], buf[30], buf[31],
 951                                 buf[32], buf[33], buf[34], buf[35],
 952                                 buf[36], buf[37], buf[38], buf[39],
 953                                 buf[40], buf[41], buf[42], buf[43],
 954                                 buf[44], buf[45], buf[46], buf[47],
 955                                 buf[48], buf[49], buf[50], buf[51],
 956                                 buf[52], buf[53], buf[54], buf[55],
 957                                 buf[56], buf[57], buf[58], buf[59],
 958                                 buf[60], buf[61], buf[62], buf[63]);
 959                 } else if (val & FBTFT_OF_INIT_DELAY) {
 960                         fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
 961                                       "init: msleep(%u)\n", val & 0xFFFF);
 962                         msleep(val & 0xFFFF);
 963                         val = values[++index];
 964                 } else {
 965                         dev_err(dev, "illegal init value 0x%X\n", val);
 966                         ret = -EINVAL;
 967                         goto out_free;
 968                 }
 969         }
 970
 971 out_free:
 972         kfree(values);
 973         return ret;
 974 }
 975
 976 /**
 977  * fbtft_init_display() - Generic init_display() function
 978  * @par: Driver data
 979  *
 980  * Uses par->init_sequence to do the initialization
 981  *
 982  * Return: 0 if successful, negative if error
 983  */
 984 int fbtft_init_display(struct fbtft_par *par)
 985 {
 986         int buf[64];
 987         int i;
 988         int j;
 989
 990         /* sanity check */
 991         if (!par->init_sequence) {
 992                 dev_err(par->info->device,
 993                         "error: init_sequence is not set\n");
 994                 return -EINVAL;
 995         }
 996
 997         /* make sure stop marker exists */
 998         for (i = 0; i < FBTFT_MAX_INIT_SEQUENCE; i++) {
 999                 if (par->init_sequence[i] == -3)
1000                         break;
1001         }
1002
1003         if (i == FBTFT_MAX_INIT_SEQUENCE) {
1004                 dev_err(par->info->device,
1005                         "missing stop marker at end of init sequence\n");
1006                 return -EINVAL;
1007         }
1008
1009         par->fbtftops.reset(par);
1010
1011         i = 0;
1012         while (i < FBTFT_MAX_INIT_SEQUENCE) {
1013                 if (par->init_sequence[i] == -3) {
1014                         /* done */
1015                         return 0;
1016                 }
1017                 if (par->init_sequence[i] >= 0) {
1018                         dev_err(par->info->device,
1019                                 "missing delimiter at position %d\n", i);
1020                         return -EINVAL;
1021                 }
1022                 if (par->init_sequence[i + 1] < 0) {
1023                         dev_err(par->info->device,
1024                                 "missing value after delimiter %d at position %d\n",
1025                                 par->init_sequence[i], i);
1026                         return -EINVAL;
1027                 }
1028                 switch (par->init_sequence[i]) {
1029                 case -1:
1030                         i++;
1031
1032                         /* make debug message */
1033                         for (j = 0; par->init_sequence[i + 1 + j] >= 0; j++)
1034                                 ;
1035
1036                         fbtft_par_dbg_hex(DEBUG_INIT_DISPLAY, par, par->info->device,
1037                                           s16, &par->init_sequence[i + 1], j,
1038                                           "init: write(0x%02X)", par->init_sequence[i]);
1039
1040                         /* Write */
1041                         j = 0;
1042                         while (par->init_sequence[i] >= 0) {
1043                                 if (j > 63) {
1044                                         dev_err(par->info->device,
1045                                                 "%s: Maximum register values exceeded\n",
1046                                                 __func__);
1047                                         return -EINVAL;
1048                                 }
1049                                 buf[j++] = par->init_sequence[i++];
1050                         }
1051                         par->fbtftops.write_register(par, j,
1052                                 buf[0], buf[1], buf[2], buf[3],
1053                                 buf[4], buf[5], buf[6], buf[7],
1054                                 buf[8], buf[9], buf[10], buf[11],
1055                                 buf[12], buf[13], buf[14], buf[15],
1056                                 buf[16], buf[17], buf[18], buf[19],
1057                                 buf[20], buf[21], buf[22], buf[23],
1058                                 buf[24], buf[25], buf[26], buf[27],
1059                                 buf[28], buf[29], buf[30], buf[31],
1060                                 buf[32], buf[33], buf[34], buf[35],
1061                                 buf[36], buf[37], buf[38], buf[39],
1062                                 buf[40], buf[41], buf[42], buf[43],
1063                                 buf[44], buf[45], buf[46], buf[47],
1064                                 buf[48], buf[49], buf[50], buf[51],
1065                                 buf[52], buf[53], buf[54], buf[55],
1066                                 buf[56], buf[57], buf[58], buf[59],
1067                                 buf[60], buf[61], buf[62], buf[63]);
1068                         break;
1069                 case -2:
1070                         i++;
1071                         fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
1072                                       "init: mdelay(%d)\n",
1073                                       par->init_sequence[i]);
1074                         mdelay(par->init_sequence[i++]);
1075                         break;
1076                 default:
1077                         dev_err(par->info->device,
1078                                 "unknown delimiter %d at position %d\n",
1079                                 par->init_sequence[i], i);
1080                         return -EINVAL;
1081                 }
1082         }
1083
1084         dev_err(par->info->device,
1085                 "%s: something is wrong. Shouldn't get here.\n", __func__);
1086         return -EINVAL;
1087 }
1088 EXPORT_SYMBOL(fbtft_init_display);
1089
1090 /**
1091  * fbtft_verify_gpios() - Generic verify_gpios() function
1092  * @par: Driver data
1093  *
1094  * Uses @spi, @pdev and @buswidth to determine which GPIOs is needed
1095  *
1096  * Return: 0 if successful, negative if error
1097  */
1098 static int fbtft_verify_gpios(struct fbtft_par *par)
1099 {
1100         struct fbtft_platform_data *pdata = par->pdata;
1101         int i;
1102
1103         fbtft_par_dbg(DEBUG_VERIFY_GPIOS, par, "%s()\n", __func__);
1104
1105         if (pdata->display.buswidth != 9 &&  par->startbyte == 0 &&
1106             !par->gpio.dc) {
1107                 dev_err(par->info->device,
1108                         "Missing info about 'dc' gpio. Aborting.\n");
1109                 return -EINVAL;
1110         }
1111
1112         if (!par->pdev)
1113                 return 0;
1114
1115         if (!par->gpio.wr) {
1116                 dev_err(par->info->device, "Missing 'wr' gpio. Aborting.\n");
1117                 return -EINVAL;
1118         }
1119         for (i = 0; i < pdata->display.buswidth; i++) {
1120                 if (!par->gpio.db[i]) {
1121                         dev_err(par->info->device,
1122                                 "Missing 'db%02d' gpio. Aborting.\n", i);
1123                         return -EINVAL;
1124                 }
1125         }
1126
1127         return 0;
1128 }
1129
1130 /* returns 0 if the property is not present */
1131 static u32 fbtft_property_value(struct device *dev, const char *propname)
1132 {
1133         int ret;
1134         u32 val = 0;
1135
1136         ret = device_property_read_u32(dev, propname, &val);
1137         if (ret == 0)
1138                 dev_info(dev, "%s: %s = %u\n", __func__, propname, val);
1139
1140         return val;
1141 }
1142
1143 static struct fbtft_platform_data *fbtft_properties_read(struct device *dev)
1144 {
1145         struct fbtft_platform_data *pdata;
1146
1147         if (!dev_fwnode(dev)) {
1148                 dev_err(dev, "Missing platform data or properties\n");
1149                 return ERR_PTR(-EINVAL);
1150         }
1151
1152         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
1153         if (!pdata)
1154                 return ERR_PTR(-ENOMEM);
1155
1156         pdata->display.width = fbtft_property_value(dev, "width");
1157         pdata->display.height = fbtft_property_value(dev, "height");
1158         pdata->display.regwidth = fbtft_property_value(dev, "regwidth");
1159         pdata->display.buswidth = fbtft_property_value(dev, "buswidth");
1160         pdata->display.backlight = fbtft_property_value(dev, "backlight");
1161         pdata->display.bpp = fbtft_property_value(dev, "bpp");
1162         pdata->display.debug = fbtft_property_value(dev, "debug");
1163         pdata->rotate = fbtft_property_value(dev, "rotate");
1164         pdata->bgr = device_property_read_bool(dev, "bgr");
1165         pdata->fps = fbtft_property_value(dev, "fps");
1166         pdata->txbuflen = fbtft_property_value(dev, "txbuflen");
1167         pdata->startbyte = fbtft_property_value(dev, "startbyte");
1168         device_property_read_string(dev, "gamma", (const char **)&pdata->gamma);
1169
1170         if (device_property_present(dev, "led-gpios"))
1171                 pdata->display.backlight = 1;
1172         if (device_property_present(dev, "init"))
1173                 pdata->display.fbtftops.init_display =
1174                         fbtft_init_display_from_property;
1175
1176         pdata->display.fbtftops.request_gpios = fbtft_request_gpios;
1177
1178         return pdata;
1179 }
1180
1181 /**
1182  * fbtft_probe_common() - Generic device probe() helper function
1183  * @display: Display properties
1184  * @sdev: SPI device
1185  * @pdev: Platform device
1186  *
1187  * Allocates, initializes and registers a framebuffer
1188  *
1189  * Either @sdev or @pdev should be NULL
1190  *
1191  * Return: 0 if successful, negative if error
1192  */
1193 int fbtft_probe_common(struct fbtft_display *display,
1194                        struct spi_device *sdev,
1195                        struct platform_device *pdev)
1196 {
1197         struct device *dev;
1198         struct fb_info *info;
1199         struct fbtft_par *par;
1200         struct fbtft_platform_data *pdata;
1201         int ret;
1202
1203         if (sdev)
1204                 dev = &sdev->dev;
1205         else
1206                 dev = &pdev->dev;
1207
1208         if (unlikely(display->debug & DEBUG_DRIVER_INIT_FUNCTIONS))
1209                 dev_info(dev, "%s()\n", __func__);
1210
1211         pdata = dev->platform_data;
1212         if (!pdata) {
1213                 pdata = fbtft_properties_read(dev);
1214                 if (IS_ERR(pdata))
1215                         return PTR_ERR(pdata);
1216         }
1217
1218         info = fbtft_framebuffer_alloc(display, dev, pdata);
1219         if (!info)
1220                 return -ENOMEM;
1221
1222         par = info->par;
1223         par->spi = sdev;
1224         par->pdev = pdev;
1225
1226         if (display->buswidth == 0) {
1227                 dev_err(dev, "buswidth is not set\n");
1228                 return -EINVAL;
1229         }
1230
1231         /* write register functions */
1232         if (display->regwidth == 8 && display->buswidth == 8)
1233                 par->fbtftops.write_register = fbtft_write_reg8_bus8;
1234         else if (display->regwidth == 8 && display->buswidth == 9 && par->spi)
1235                 par->fbtftops.write_register = fbtft_write_reg8_bus9;
1236         else if (display->regwidth == 16 && display->buswidth == 8)
1237                 par->fbtftops.write_register = fbtft_write_reg16_bus8;
1238         else if (display->regwidth == 16 && display->buswidth == 16)
1239                 par->fbtftops.write_register = fbtft_write_reg16_bus16;
1240         else
1241                 dev_warn(dev,
1242                          "no default functions for regwidth=%d and buswidth=%d\n",
1243                          display->regwidth, display->buswidth);
1244
1245         /* write_vmem() functions */
1246         if (display->buswidth == 8)
1247                 par->fbtftops.write_vmem = fbtft_write_vmem16_bus8;
1248         else if (display->buswidth == 9)
1249                 par->fbtftops.write_vmem = fbtft_write_vmem16_bus9;
1250         else if (display->buswidth == 16)
1251                 par->fbtftops.write_vmem = fbtft_write_vmem16_bus16;
1252
1253         /* GPIO write() functions */
1254         if (par->pdev) {
1255                 if (display->buswidth == 8)
1256                         par->fbtftops.write = fbtft_write_gpio8_wr;
1257                 else if (display->buswidth == 16)
1258                         par->fbtftops.write = fbtft_write_gpio16_wr;
1259         }
1260
1261         /* 9-bit SPI setup */
1262         if (par->spi && display->buswidth == 9) {
1263                 if (par->spi->master->bits_per_word_mask & SPI_BPW_MASK(9)) {
1264                         par->spi->bits_per_word = 9;
1265                 } else {
1266                         dev_warn(&par->spi->dev,
1267                                  "9-bit SPI not available, emulating using 8-bit.\n");
1268                         /* allocate buffer with room for dc bits */
1269                         par->extra = devm_kzalloc(par->info->device,
1270                                                   par->txbuf.len +
1271                                                   (par->txbuf.len / 8) + 8,
1272                                                   GFP_KERNEL);
1273                         if (!par->extra) {
1274                                 ret = -ENOMEM;
1275                                 goto out_release;
1276                         }
1277                         par->fbtftops.write = fbtft_write_spi_emulate_9;
1278                 }
1279         }
1280
1281         if (!par->fbtftops.verify_gpios)
1282                 par->fbtftops.verify_gpios = fbtft_verify_gpios;
1283
1284         /* make sure we still use the driver provided functions */
1285         fbtft_merge_fbtftops(&par->fbtftops, &display->fbtftops);
1286
1287         /* use init_sequence if provided */
1288         if (par->init_sequence)
1289                 par->fbtftops.init_display = fbtft_init_display;
1290
1291         /* use platform_data provided functions above all */
1292         fbtft_merge_fbtftops(&par->fbtftops, &pdata->display.fbtftops);
1293
1294         ret = fbtft_register_framebuffer(info);
1295         if (ret < 0)
1296                 goto out_release;
1297
1298         return 0;
1299
1300 out_release:
1301         fbtft_framebuffer_release(info);
1302
1303         return ret;
1304 }
1305 EXPORT_SYMBOL(fbtft_probe_common);
1306
1307 /**
1308  * fbtft_remove_common() - Generic device remove() helper function
1309  * @dev: Device
1310  * @info: Framebuffer
1311  *
1312  * Unregisters and releases the framebuffer
1313  */
1314 void fbtft_remove_common(struct device *dev, struct fb_info *info)
1315 {
1316         struct fbtft_par *par;
1317
1318         par = info->par;
1319         if (par)
1320                 fbtft_par_dbg(DEBUG_DRIVER_INIT_FUNCTIONS, par,
1321                               "%s()\n", __func__);
1322         fbtft_unregister_framebuffer(info);
1323         fbtft_framebuffer_release(info);
1324 }
1325 EXPORT_SYMBOL(fbtft_remove_common);
1326
1327 MODULE_LICENSE("GPL");