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 ((bd->props.power == FB_BLANK_UNBLANK) &&
 141             (bd->props.fb_blank == FB_BLANK_UNBLANK))
 142                 gpiod_set_value(par->gpio.led[0], polarity);
 143         else
 144                 gpiod_set_value(par->gpio.led[0], !polarity);
 145
 146         return 0;
 147 }
 148
 149 static int fbtft_backlight_get_brightness(struct backlight_device *bd)
 150 {
 151         return bd->props.brightness;
 152 }
 153
 154 void fbtft_unregister_backlight(struct fbtft_par *par)
 155 {
 156         if (par->info->bl_dev) {
 157                 par->info->bl_dev->props.power = FB_BLANK_POWERDOWN;
 158                 backlight_update_status(par->info->bl_dev);
 159                 backlight_device_unregister(par->info->bl_dev);
 160                 par->info->bl_dev = NULL;
 161         }
 162 }
 163 EXPORT_SYMBOL(fbtft_unregister_backlight);
 164
 165 static const struct backlight_ops fbtft_bl_ops = {
 166         .get_brightness = fbtft_backlight_get_brightness,
 167         .update_status  = fbtft_backlight_update_status,
 168 };
 169
 170 void fbtft_register_backlight(struct fbtft_par *par)
 171 {
 172         struct backlight_device *bd;
 173         struct backlight_properties bl_props = { 0, };
 174
 175         if (!par->gpio.led[0]) {
 176                 fbtft_par_dbg(DEBUG_BACKLIGHT, par,
 177                               "%s(): led pin not set, exiting.\n", __func__);
 178                 return;
 179         }
 180
 181         bl_props.type = BACKLIGHT_RAW;
 182         /* Assume backlight is off, get polarity from current state of pin */
 183         bl_props.power = FB_BLANK_POWERDOWN;
 184         if (!gpiod_get_value(par->gpio.led[0]))
 185                 par->polarity = true;
 186
 187         bd = backlight_device_register(dev_driver_string(par->info->device),
 188                                        par->info->device, par,
 189                                        &fbtft_bl_ops, &bl_props);
 190         if (IS_ERR(bd)) {
 191                 dev_err(par->info->device,
 192                         "cannot register backlight device (%ld)\n",
 193                         PTR_ERR(bd));
 194                 return;
 195         }
 196         par->info->bl_dev = bd;
 197
 198         if (!par->fbtftops.unregister_backlight)
 199                 par->fbtftops.unregister_backlight = fbtft_unregister_backlight;
 200 }
 201 EXPORT_SYMBOL(fbtft_register_backlight);
 202
 203 static void fbtft_set_addr_win(struct fbtft_par *par, int xs, int ys, int xe,
 204                                int ye)
 205 {
 206         write_reg(par, MIPI_DCS_SET_COLUMN_ADDRESS,
 207                   (xs >> 8) & 0xFF, xs & 0xFF, (xe >> 8) & 0xFF, xe & 0xFF);
 208
 209         write_reg(par, MIPI_DCS_SET_PAGE_ADDRESS,
 210                   (ys >> 8) & 0xFF, ys & 0xFF, (ye >> 8) & 0xFF, ye & 0xFF);
 211
 212         write_reg(par, MIPI_DCS_WRITE_MEMORY_START);
 213 }
 214
 215 static void fbtft_reset(struct fbtft_par *par)
 216 {
 217         if (!par->gpio.reset)
 218                 return;
 219
 220         fbtft_par_dbg(DEBUG_RESET, par, "%s()\n", __func__);
 221
 222         gpiod_set_value_cansleep(par->gpio.reset, 1);
 223         usleep_range(20, 40);
 224         gpiod_set_value_cansleep(par->gpio.reset, 0);
 225         msleep(120);
 226
 227         gpiod_set_value_cansleep(par->gpio.cs, 1);  /* Activate chip */
 228 }
 229
 230 static void fbtft_update_display(struct fbtft_par *par, unsigned int start_line,
 231                                  unsigned int end_line)
 232 {
 233         size_t offset, len;
 234         ktime_t ts_start, ts_end;
 235         long fps, throughput;
 236         bool timeit = false;
 237         int ret = 0;
 238
 239         if (unlikely(par->debug & (DEBUG_TIME_FIRST_UPDATE |
 240                         DEBUG_TIME_EACH_UPDATE))) {
 241                 if ((par->debug & DEBUG_TIME_EACH_UPDATE) ||
 242                     ((par->debug & DEBUG_TIME_FIRST_UPDATE) &&
 243                     !par->first_update_done)) {
 244                         ts_start = ktime_get();
 245                         timeit = true;
 246                 }
 247         }
 248
 249         /* Sanity checks */
 250         if (start_line > end_line) {
 251                 dev_warn(par->info->device,
 252                          "%s: start_line=%u is larger than end_line=%u. Shouldn't happen, will do full display update\n",
 253                          __func__, start_line, end_line);
 254                 start_line = 0;
 255                 end_line = par->info->var.yres - 1;
 256         }
 257         if (start_line > par->info->var.yres - 1 ||
 258             end_line > par->info->var.yres - 1) {
 259                 dev_warn(par->info->device,
 260                          "%s: start_line=%u or end_line=%u is larger than max=%d. Shouldn't happen, will do full display update\n",
 261                          __func__, start_line,
 262                          end_line, par->info->var.yres - 1);
 263                 start_line = 0;
 264                 end_line = par->info->var.yres - 1;
 265         }
 266
 267         fbtft_par_dbg(DEBUG_UPDATE_DISPLAY, par, "%s(start_line=%u, end_line=%u)\n",
 268                       __func__, start_line, end_line);
 269
 270         if (par->fbtftops.set_addr_win)
 271                 par->fbtftops.set_addr_win(par, 0, start_line,
 272                                 par->info->var.xres - 1, end_line);
 273
 274         offset = start_line * par->info->fix.line_length;
 275         len = (end_line - start_line + 1) * par->info->fix.line_length;
 276         ret = par->fbtftops.write_vmem(par, offset, len);
 277         if (ret < 0)
 278                 dev_err(par->info->device,
 279                         "%s: write_vmem failed to update display buffer\n",
 280                         __func__);
 281
 282         if (unlikely(timeit)) {
 283                 ts_end = ktime_get();
 284                 if (!ktime_to_ns(par->update_time))
 285                         par->update_time = ts_start;
 286
 287                 fps = ktime_us_delta(ts_start, par->update_time);
 288                 par->update_time = ts_start;
 289                 fps = fps ? 1000000 / fps : 0;
 290
 291                 throughput = ktime_us_delta(ts_end, ts_start);
 292                 throughput = throughput ? (len * 1000) / throughput : 0;
 293                 throughput = throughput * 1000 / 1024;
 294
 295                 dev_info(par->info->device,
 296                          "Display update: %ld kB/s, fps=%ld\n",
 297                          throughput, fps);
 298                 par->first_update_done = true;
 299         }
 300 }
 301
 302 static void fbtft_mkdirty(struct fb_info *info, int y, int height)
 303 {
 304         struct fbtft_par *par = info->par;
 305         struct fb_deferred_io *fbdefio = info->fbdefio;
 306
 307         /* special case, needed ? */
 308         if (y == -1) {
 309                 y = 0;
 310                 height = info->var.yres;
 311         }
 312
 313         /* Mark display lines/area as dirty */
 314         spin_lock(&par->dirty_lock);
 315         if (y < par->dirty_lines_start)
 316                 par->dirty_lines_start = y;
 317         if (y + height - 1 > par->dirty_lines_end)
 318                 par->dirty_lines_end = y + height - 1;
 319         spin_unlock(&par->dirty_lock);
 320
 321         /* Schedule deferred_io to update display (no-op if already on queue)*/
 322         schedule_delayed_work(&info->deferred_work, fbdefio->delay);
 323 }
 324
 325 static void fbtft_deferred_io(struct fb_info *info, struct list_head *pagelist)
 326 {
 327         struct fbtft_par *par = info->par;
 328         unsigned int dirty_lines_start, dirty_lines_end;
 329         struct page *page;
 330         unsigned long index;
 331         unsigned int y_low = 0, y_high = 0;
 332         int count = 0;
 333
 334         spin_lock(&par->dirty_lock);
 335         dirty_lines_start = par->dirty_lines_start;
 336         dirty_lines_end = par->dirty_lines_end;
 337         /* set display line markers as clean */
 338         par->dirty_lines_start = par->info->var.yres - 1;
 339         par->dirty_lines_end = 0;
 340         spin_unlock(&par->dirty_lock);
 341
 342         /* Mark display lines as dirty */
 343         list_for_each_entry(page, pagelist, lru) {
 344                 count++;
 345                 index = page->index << PAGE_SHIFT;
 346                 y_low = index / info->fix.line_length;
 347                 y_high = (index + PAGE_SIZE - 1) / info->fix.line_length;
 348                 dev_dbg(info->device,
 349                         "page->index=%lu y_low=%d y_high=%d\n",
 350                         page->index, y_low, y_high);
 351                 if (y_high > info->var.yres - 1)
 352                         y_high = info->var.yres - 1;
 353                 if (y_low < dirty_lines_start)
 354                         dirty_lines_start = y_low;
 355                 if (y_high > dirty_lines_end)
 356                         dirty_lines_end = y_high;
 357         }
 358
 359         par->fbtftops.update_display(info->par,
 360                                         dirty_lines_start, dirty_lines_end);
 361 }
 362
 363 static void fbtft_fb_fillrect(struct fb_info *info,
 364                               const struct fb_fillrect *rect)
 365 {
 366         struct fbtft_par *par = info->par;
 367
 368         dev_dbg(info->dev,
 369                 "%s: dx=%d, dy=%d, width=%d, height=%d\n",
 370                 __func__, rect->dx, rect->dy, rect->width, rect->height);
 371         sys_fillrect(info, rect);
 372
 373         par->fbtftops.mkdirty(info, rect->dy, rect->height);
 374 }
 375
 376 static void fbtft_fb_copyarea(struct fb_info *info,
 377                               const struct fb_copyarea *area)
 378 {
 379         struct fbtft_par *par = info->par;
 380
 381         dev_dbg(info->dev,
 382                 "%s: dx=%d, dy=%d, width=%d, height=%d\n",
 383                 __func__,  area->dx, area->dy, area->width, area->height);
 384         sys_copyarea(info, area);
 385
 386         par->fbtftops.mkdirty(info, area->dy, area->height);
 387 }
 388
 389 static void fbtft_fb_imageblit(struct fb_info *info,
 390                                const struct fb_image *image)
 391 {
 392         struct fbtft_par *par = info->par;
 393
 394         dev_dbg(info->dev,
 395                 "%s: dx=%d, dy=%d, width=%d, height=%d\n",
 396                 __func__,  image->dx, image->dy, image->width, image->height);
 397         sys_imageblit(info, image);
 398
 399         par->fbtftops.mkdirty(info, image->dy, image->height);
 400 }
 401
 402 static ssize_t fbtft_fb_write(struct fb_info *info, const char __user *buf,
 403                               size_t count, loff_t *ppos)
 404 {
 405         struct fbtft_par *par = info->par;
 406         ssize_t res;
 407
 408         dev_dbg(info->dev,
 409                 "%s: count=%zd, ppos=%llu\n", __func__,  count, *ppos);
 410         res = fb_sys_write(info, buf, count, ppos);
 411
 412         /* TODO: only mark changed area update all for now */
 413         par->fbtftops.mkdirty(info, -1, 0);
 414
 415         return res;
 416 }
 417
 418 /* from pxafb.c */
 419 static unsigned int chan_to_field(unsigned int chan, struct fb_bitfield *bf)
 420 {
 421         chan &= 0xffff;
 422         chan >>= 16 - bf->length;
 423         return chan << bf->offset;
 424 }
 425
 426 static int fbtft_fb_setcolreg(unsigned int regno, unsigned int red,
 427                               unsigned int green, unsigned int blue,
 428                               unsigned int transp, struct fb_info *info)
 429 {
 430         unsigned int val;
 431         int ret = 1;
 432
 433         dev_dbg(info->dev,
 434                 "%s(regno=%u, red=0x%X, green=0x%X, blue=0x%X, trans=0x%X)\n",
 435                 __func__, regno, red, green, blue, transp);
 436
 437         switch (info->fix.visual) {
 438         case FB_VISUAL_TRUECOLOR:
 439                 if (regno < 16) {
 440                         u32 *pal = info->pseudo_palette;
 441
 442                         val  = chan_to_field(red,   &info->var.red);
 443                         val |= chan_to_field(green, &info->var.green);
 444                         val |= chan_to_field(blue,  &info->var.blue);
 445
 446                         pal[regno] = val;
 447                         ret = 0;
 448                 }
 449                 break;
 450         }
 451         return ret;
 452 }
 453
 454 static int fbtft_fb_blank(int blank, struct fb_info *info)
 455 {
 456         struct fbtft_par *par = info->par;
 457         int ret = -EINVAL;
 458
 459         dev_dbg(info->dev, "%s(blank=%d)\n",
 460                 __func__, blank);
 461
 462         if (!par->fbtftops.blank)
 463                 return ret;
 464
 465         switch (blank) {
 466         case FB_BLANK_POWERDOWN:
 467         case FB_BLANK_VSYNC_SUSPEND:
 468         case FB_BLANK_HSYNC_SUSPEND:
 469         case FB_BLANK_NORMAL:
 470                 ret = par->fbtftops.blank(par, true);
 471                 break;
 472         case FB_BLANK_UNBLANK:
 473                 ret = par->fbtftops.blank(par, false);
 474                 break;
 475         }
 476         return ret;
 477 }
 478
 479 static void fbtft_merge_fbtftops(struct fbtft_ops *dst, struct fbtft_ops *src)
 480 {
 481         if (src->write)
 482                 dst->write = src->write;
 483         if (src->read)
 484                 dst->read = src->read;
 485         if (src->write_vmem)
 486                 dst->write_vmem = src->write_vmem;
 487         if (src->write_register)
 488                 dst->write_register = src->write_register;
 489         if (src->set_addr_win)
 490                 dst->set_addr_win = src->set_addr_win;
 491         if (src->reset)
 492                 dst->reset = src->reset;
 493         if (src->mkdirty)
 494                 dst->mkdirty = src->mkdirty;
 495         if (src->update_display)
 496                 dst->update_display = src->update_display;
 497         if (src->init_display)
 498                 dst->init_display = src->init_display;
 499         if (src->blank)
 500                 dst->blank = src->blank;
 501         if (src->request_gpios_match)
 502                 dst->request_gpios_match = src->request_gpios_match;
 503         if (src->request_gpios)
 504                 dst->request_gpios = src->request_gpios;
 505         if (src->verify_gpios)
 506                 dst->verify_gpios = src->verify_gpios;
 507         if (src->register_backlight)
 508                 dst->register_backlight = src->register_backlight;
 509         if (src->unregister_backlight)
 510                 dst->unregister_backlight = src->unregister_backlight;
 511         if (src->set_var)
 512                 dst->set_var = src->set_var;
 513         if (src->set_gamma)
 514                 dst->set_gamma = src->set_gamma;
 515 }
 516
 517 /**
 518  * fbtft_framebuffer_alloc - creates a new frame buffer info structure
 519  *
 520  * @display: pointer to structure describing the display
 521  * @dev: pointer to the device for this fb, this can be NULL
 522  * @pdata: platform data for the display in use
 523  *
 524  * Creates a new frame buffer info structure.
 525  *
 526  * Also creates and populates the following structures:
 527  *   info->fbops
 528  *   info->fbdefio
 529  *   info->pseudo_palette
 530  *   par->fbtftops
 531  *   par->txbuf
 532  *
 533  * Returns the new structure, or NULL if an error occurred.
 534  *
 535  */
 536 struct fb_info *fbtft_framebuffer_alloc(struct fbtft_display *display,
 537                                         struct device *dev,
 538                                         struct fbtft_platform_data *pdata)
 539 {
 540         struct fb_info *info;
 541         struct fbtft_par *par;
 542         struct fb_ops *fbops = NULL;
 543         struct fb_deferred_io *fbdefio = NULL;
 544         u8 *vmem = NULL;
 545         void *txbuf = NULL;
 546         void *buf = NULL;
 547         unsigned int width;
 548         unsigned int height;
 549         int txbuflen = display->txbuflen;
 550         unsigned int bpp = display->bpp;
 551         unsigned int fps = display->fps;
 552         int vmem_size;
 553         const s16 *init_sequence = display->init_sequence;
 554         char *gamma = display->gamma;
 555         u32 *gamma_curves = NULL;
 556
 557         /* sanity check */
 558         if (display->gamma_num * display->gamma_len >
 559                         FBTFT_GAMMA_MAX_VALUES_TOTAL) {
 560                 dev_err(dev, "FBTFT_GAMMA_MAX_VALUES_TOTAL=%d is exceeded\n",
 561                         FBTFT_GAMMA_MAX_VALUES_TOTAL);
 562                 return NULL;
 563         }
 564
 565         /* defaults */
 566         if (!fps)
 567                 fps = 20;
 568         if (!bpp)
 569                 bpp = 16;
 570
 571         if (!pdata) {
 572                 dev_err(dev, "platform data is missing\n");
 573                 return NULL;
 574         }
 575
 576         /* override driver values? */
 577         if (pdata->fps)
 578                 fps = pdata->fps;
 579         if (pdata->txbuflen)
 580                 txbuflen = pdata->txbuflen;
 581         if (pdata->display.init_sequence)
 582                 init_sequence = pdata->display.init_sequence;
 583         if (pdata->gamma)
 584                 gamma = pdata->gamma;
 585         if (pdata->display.debug)
 586                 display->debug = pdata->display.debug;
 587         if (pdata->display.backlight)
 588                 display->backlight = pdata->display.backlight;
 589         if (pdata->display.width)
 590                 display->width = pdata->display.width;
 591         if (pdata->display.height)
 592                 display->height = pdata->display.height;
 593         if (pdata->display.buswidth)
 594                 display->buswidth = pdata->display.buswidth;
 595         if (pdata->display.regwidth)
 596                 display->regwidth = pdata->display.regwidth;
 597
 598         display->debug |= debug;
 599         fbtft_expand_debug_value(&display->debug);
 600
 601         switch (pdata->rotate) {
 602         case 90:
 603         case 270:
 604                 width =  display->height;
 605                 height = display->width;
 606                 break;
 607         default:
 608                 width =  display->width;
 609                 height = display->height;
 610         }
 611
 612         vmem_size = display->width * display->height * bpp / 8;
 613         vmem = vzalloc(vmem_size);
 614         if (!vmem)
 615                 goto alloc_fail;
 616
 617         fbops = devm_kzalloc(dev, sizeof(struct fb_ops), GFP_KERNEL);
 618         if (!fbops)
 619                 goto alloc_fail;
 620
 621         fbdefio = devm_kzalloc(dev, sizeof(struct fb_deferred_io), GFP_KERNEL);
 622         if (!fbdefio)
 623                 goto alloc_fail;
 624
 625         buf = devm_kzalloc(dev, 128, GFP_KERNEL);
 626         if (!buf)
 627                 goto alloc_fail;
 628
 629         if (display->gamma_num && display->gamma_len) {
 630                 gamma_curves = devm_kcalloc(dev,
 631                                             display->gamma_num *
 632                                             display->gamma_len,
 633                                             sizeof(gamma_curves[0]),
 634                                             GFP_KERNEL);
 635                 if (!gamma_curves)
 636                         goto alloc_fail;
 637         }
 638
 639         info = framebuffer_alloc(sizeof(struct fbtft_par), dev);
 640         if (!info)
 641                 goto alloc_fail;
 642
 643         info->screen_buffer = vmem;
 644         info->fbops = fbops;
 645         info->fbdefio = fbdefio;
 646
 647         fbops->owner        =      dev->driver->owner;
 648         fbops->fb_read      =      fb_sys_read;
 649         fbops->fb_write     =      fbtft_fb_write;
 650         fbops->fb_fillrect  =      fbtft_fb_fillrect;
 651         fbops->fb_copyarea  =      fbtft_fb_copyarea;
 652         fbops->fb_imageblit =      fbtft_fb_imageblit;
 653         fbops->fb_setcolreg =      fbtft_fb_setcolreg;
 654         fbops->fb_blank     =      fbtft_fb_blank;
 655
 656         fbdefio->delay =           HZ / fps;
 657         fbdefio->sort_pagelist =   true;
 658         fbdefio->deferred_io =     fbtft_deferred_io;
 659         fb_deferred_io_init(info);
 660
 661         snprintf(info->fix.id, sizeof(info->fix.id), "%s", dev->driver->name);
 662         info->fix.type =           FB_TYPE_PACKED_PIXELS;
 663         info->fix.visual =         FB_VISUAL_TRUECOLOR;
 664         info->fix.xpanstep =       0;
 665         info->fix.ypanstep =       0;
 666         info->fix.ywrapstep =      0;
 667         info->fix.line_length =    width * bpp / 8;
 668         info->fix.accel =          FB_ACCEL_NONE;
 669         info->fix.smem_len =       vmem_size;
 670
 671         info->var.rotate =         pdata->rotate;
 672         info->var.xres =           width;
 673         info->var.yres =           height;
 674         info->var.xres_virtual =   info->var.xres;
 675         info->var.yres_virtual =   info->var.yres;
 676         info->var.bits_per_pixel = bpp;
 677         info->var.nonstd =         1;
 678
 679         /* RGB565 */
 680         info->var.red.offset =     11;
 681         info->var.red.length =     5;
 682         info->var.green.offset =   5;
 683         info->var.green.length =   6;
 684         info->var.blue.offset =    0;
 685         info->var.blue.length =    5;
 686         info->var.transp.offset =  0;
 687         info->var.transp.length =  0;
 688
 689         info->flags =              FBINFO_FLAG_DEFAULT | FBINFO_VIRTFB;
 690
 691         par = info->par;
 692         par->info = info;
 693         par->pdata = pdata;
 694         par->debug = display->debug;
 695         par->buf = buf;
 696         spin_lock_init(&par->dirty_lock);
 697         par->bgr = pdata->bgr;
 698         par->startbyte = pdata->startbyte;
 699         par->init_sequence = init_sequence;
 700         par->gamma.curves = gamma_curves;
 701         par->gamma.num_curves = display->gamma_num;
 702         par->gamma.num_values = display->gamma_len;
 703         mutex_init(&par->gamma.lock);
 704         info->pseudo_palette = par->pseudo_palette;
 705
 706         if (par->gamma.curves && gamma) {
 707                 if (fbtft_gamma_parse_str(par, par->gamma.curves, gamma,
 708                                           strlen(gamma)))
 709                         goto release_framebuf;
 710         }
 711
 712         /* Transmit buffer */
 713         if (txbuflen == -1)
 714                 txbuflen = vmem_size + 2; /* add in case startbyte is used */
 715         if (txbuflen >= vmem_size + 2)
 716                 txbuflen = 0;
 717
 718 #ifdef __LITTLE_ENDIAN
 719         if ((!txbuflen) && (bpp > 8))
 720                 txbuflen = PAGE_SIZE; /* need buffer for byteswapping */
 721 #endif
 722
 723         if (txbuflen > 0) {
 724                 txbuf = devm_kzalloc(par->info->device, txbuflen, GFP_KERNEL);
 725                 if (!txbuf)
 726                         goto release_framebuf;
 727                 par->txbuf.buf = txbuf;
 728                 par->txbuf.len = txbuflen;
 729         }
 730
 731         /* default fbtft operations */
 732         par->fbtftops.write = fbtft_write_spi;
 733         par->fbtftops.read = fbtft_read_spi;
 734         par->fbtftops.write_vmem = fbtft_write_vmem16_bus8;
 735         par->fbtftops.write_register = fbtft_write_reg8_bus8;
 736         par->fbtftops.set_addr_win = fbtft_set_addr_win;
 737         par->fbtftops.reset = fbtft_reset;
 738         par->fbtftops.mkdirty = fbtft_mkdirty;
 739         par->fbtftops.update_display = fbtft_update_display;
 740         if (display->backlight)
 741                 par->fbtftops.register_backlight = fbtft_register_backlight;
 742
 743         /* use driver provided functions */
 744         fbtft_merge_fbtftops(&par->fbtftops, &display->fbtftops);
 745
 746         return info;
 747
 748 release_framebuf:
 749         framebuffer_release(info);
 750
 751 alloc_fail:
 752         vfree(vmem);
 753
 754         return NULL;
 755 }
 756 EXPORT_SYMBOL(fbtft_framebuffer_alloc);
 757
 758 /**
 759  * fbtft_framebuffer_release - frees up all memory used by the framebuffer
 760  *
 761  * @info: frame buffer info structure
 762  *
 763  */
 764 void fbtft_framebuffer_release(struct fb_info *info)
 765 {
 766         fb_deferred_io_cleanup(info);
 767         vfree(info->screen_buffer);
 768         framebuffer_release(info);
 769 }
 770 EXPORT_SYMBOL(fbtft_framebuffer_release);
 771
 772 /**
 773  *      fbtft_register_framebuffer - registers a tft frame buffer device
 774  *      @fb_info: frame buffer info structure
 775  *
 776  *  Sets SPI driverdata if needed
 777  *  Requests needed gpios.
 778  *  Initializes display
 779  *  Updates display.
 780  *      Registers a frame buffer device @fb_info.
 781  *
 782  *      Returns negative errno on error, or zero for success.
 783  *
 784  */
 785 int fbtft_register_framebuffer(struct fb_info *fb_info)
 786 {
 787         int ret;
 788         char text1[50] = "";
 789         char text2[50] = "";
 790         struct fbtft_par *par = fb_info->par;
 791         struct spi_device *spi = par->spi;
 792
 793         /* sanity checks */
 794         if (!par->fbtftops.init_display) {
 795                 dev_err(fb_info->device, "missing fbtftops.init_display()\n");
 796                 return -EINVAL;
 797         }
 798
 799         if (spi)
 800                 spi_set_drvdata(spi, fb_info);
 801         if (par->pdev)
 802                 platform_set_drvdata(par->pdev, fb_info);
 803
 804         ret = par->fbtftops.request_gpios(par);
 805         if (ret < 0)
 806                 goto reg_fail;
 807
 808         if (par->fbtftops.verify_gpios) {
 809                 ret = par->fbtftops.verify_gpios(par);
 810                 if (ret < 0)
 811                         goto reg_fail;
 812         }
 813
 814         ret = par->fbtftops.init_display(par);
 815         if (ret < 0)
 816                 goto reg_fail;
 817         if (par->fbtftops.set_var) {
 818                 ret = par->fbtftops.set_var(par);
 819                 if (ret < 0)
 820                         goto reg_fail;
 821         }
 822
 823         /* update the entire display */
 824         par->fbtftops.update_display(par, 0, par->info->var.yres - 1);
 825
 826         if (par->fbtftops.set_gamma && par->gamma.curves) {
 827                 ret = par->fbtftops.set_gamma(par, par->gamma.curves);
 828                 if (ret)
 829                         goto reg_fail;
 830         }
 831
 832         if (par->fbtftops.register_backlight)
 833                 par->fbtftops.register_backlight(par);
 834
 835         ret = register_framebuffer(fb_info);
 836         if (ret < 0)
 837                 goto reg_fail;
 838
 839         fbtft_sysfs_init(par);
 840
 841         if (par->txbuf.buf && par->txbuf.len >= 1024)
 842                 sprintf(text1, ", %zu KiB buffer memory", par->txbuf.len >> 10);
 843         if (spi)
 844                 sprintf(text2, ", spi%d.%d at %d MHz", spi->master->bus_num,
 845                         spi->chip_select, spi->max_speed_hz / 1000000);
 846         dev_info(fb_info->dev,
 847                  "%s frame buffer, %dx%d, %d KiB video memory%s, fps=%lu%s\n",
 848                  fb_info->fix.id, fb_info->var.xres, fb_info->var.yres,
 849                  fb_info->fix.smem_len >> 10, text1,
 850                  HZ / fb_info->fbdefio->delay, text2);
 851
 852         /* Turn on backlight if available */
 853         if (fb_info->bl_dev) {
 854                 fb_info->bl_dev->props.power = FB_BLANK_UNBLANK;
 855                 fb_info->bl_dev->ops->update_status(fb_info->bl_dev);
 856         }
 857
 858         return 0;
 859
 860 reg_fail:
 861         if (par->fbtftops.unregister_backlight)
 862                 par->fbtftops.unregister_backlight(par);
 863
 864         return ret;
 865 }
 866 EXPORT_SYMBOL(fbtft_register_framebuffer);
 867
 868 /**
 869  *      fbtft_unregister_framebuffer - releases a tft frame buffer device
 870  *      @fb_info: frame buffer info structure
 871  *
 872  *  Frees SPI driverdata if needed
 873  *  Frees gpios.
 874  *      Unregisters frame buffer device.
 875  *
 876  */
 877 int fbtft_unregister_framebuffer(struct fb_info *fb_info)
 878 {
 879         struct fbtft_par *par = fb_info->par;
 880
 881         if (par->fbtftops.unregister_backlight)
 882                 par->fbtftops.unregister_backlight(par);
 883         fbtft_sysfs_exit(par);
 884         unregister_framebuffer(fb_info);
 885
 886         return 0;
 887 }
 888 EXPORT_SYMBOL(fbtft_unregister_framebuffer);
 889
 890 /**
 891  * fbtft_init_display_from_property() - Device Tree init_display() function
 892  * @par: Driver data
 893  *
 894  * Return: 0 if successful, negative if error
 895  */
 896 static int fbtft_init_display_from_property(struct fbtft_par *par)
 897 {
 898         struct device *dev = par->info->device;
 899         int buf[64], count, index, i, j, ret;
 900         u32 *values;
 901         u32 val;
 902
 903         count = device_property_count_u32(dev, "init");
 904         if (count < 0)
 905                 return count;
 906         if (count == 0)
 907                 return -EINVAL;
 908
 909         values = kmalloc_array(count + 1, sizeof(*values), GFP_KERNEL);
 910         if (!values)
 911                 return -ENOMEM;
 912
 913         ret = device_property_read_u32_array(dev, "init", values, count);
 914         if (ret)
 915                 goto out_free;
 916
 917         par->fbtftops.reset(par);
 918
 919         index = -1;
 920         val = values[++index];
 921
 922         while (index < count) {
 923                 if (val & FBTFT_OF_INIT_CMD) {
 924                         val &= 0xFFFF;
 925                         i = 0;
 926                         while ((index < count) && !(val & 0xFFFF0000)) {
 927                                 if (i > 63) {
 928                                         dev_err(dev,
 929                                                 "%s: Maximum register values exceeded\n",
 930                                                 __func__);
 931                                         ret = -EINVAL;
 932                                         goto out_free;
 933                                 }
 934                                 buf[i++] = val;
 935                                 val = values[++index];
 936                         }
 937                         /* make debug message */
 938                         fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
 939                                       "init: write_register:\n");
 940                         for (j = 0; j < i; j++)
 941                                 fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
 942                                               "buf[%d] = %02X\n", j, buf[j]);
 943
 944                         par->fbtftops.write_register(par, i,
 945                                 buf[0], buf[1], buf[2], buf[3],
 946                                 buf[4], buf[5], buf[6], buf[7],
 947                                 buf[8], buf[9], buf[10], buf[11],
 948                                 buf[12], buf[13], buf[14], buf[15],
 949                                 buf[16], buf[17], buf[18], buf[19],
 950                                 buf[20], buf[21], buf[22], buf[23],
 951                                 buf[24], buf[25], buf[26], buf[27],
 952                                 buf[28], buf[29], buf[30], buf[31],
 953                                 buf[32], buf[33], buf[34], buf[35],
 954                                 buf[36], buf[37], buf[38], buf[39],
 955                                 buf[40], buf[41], buf[42], buf[43],
 956                                 buf[44], buf[45], buf[46], buf[47],
 957                                 buf[48], buf[49], buf[50], buf[51],
 958                                 buf[52], buf[53], buf[54], buf[55],
 959                                 buf[56], buf[57], buf[58], buf[59],
 960                                 buf[60], buf[61], buf[62], buf[63]);
 961                 } else if (val & FBTFT_OF_INIT_DELAY) {
 962                         fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
 963                                       "init: msleep(%u)\n", val & 0xFFFF);
 964                         msleep(val & 0xFFFF);
 965                         val = values[++index];
 966                 } else {
 967                         dev_err(dev, "illegal init value 0x%X\n", val);
 968                         ret = -EINVAL;
 969                         goto out_free;
 970                 }
 971         }
 972
 973 out_free:
 974         kfree(values);
 975         return ret;
 976 }
 977
 978 /**
 979  * fbtft_init_display() - Generic init_display() function
 980  * @par: Driver data
 981  *
 982  * Uses par->init_sequence to do the initialization
 983  *
 984  * Return: 0 if successful, negative if error
 985  */
 986 int fbtft_init_display(struct fbtft_par *par)
 987 {
 988         int buf[64];
 989         int i;
 990         int j;
 991
 992         /* sanity check */
 993         if (!par->init_sequence) {
 994                 dev_err(par->info->device,
 995                         "error: init_sequence is not set\n");
 996                 return -EINVAL;
 997         }
 998
 999         /* make sure stop marker exists */
1000         for (i = 0; i < FBTFT_MAX_INIT_SEQUENCE; i++) {
1001                 if (par->init_sequence[i] == -3)
1002                         break;
1003         }
1004
1005         if (i == FBTFT_MAX_INIT_SEQUENCE) {
1006                 dev_err(par->info->device,
1007                         "missing stop marker at end of init sequence\n");
1008                 return -EINVAL;
1009         }
1010
1011         par->fbtftops.reset(par);
1012
1013         i = 0;
1014         while (i < FBTFT_MAX_INIT_SEQUENCE) {
1015                 if (par->init_sequence[i] == -3) {
1016                         /* done */
1017                         return 0;
1018                 }
1019                 if (par->init_sequence[i] >= 0) {
1020                         dev_err(par->info->device,
1021                                 "missing delimiter at position %d\n", i);
1022                         return -EINVAL;
1023                 }
1024                 if (par->init_sequence[i + 1] < 0) {
1025                         dev_err(par->info->device,
1026                                 "missing value after delimiter %d at position %d\n",
1027                                 par->init_sequence[i], i);
1028                         return -EINVAL;
1029                 }
1030                 switch (par->init_sequence[i]) {
1031                 case -1:
1032                         i++;
1033
1034                         /* make debug message */
1035                         for (j = 0; par->init_sequence[i + 1 + j] >= 0; j++)
1036                                 ;
1037
1038                         fbtft_par_dbg_hex(DEBUG_INIT_DISPLAY, par, par->info->device,
1039                                           s16, &par->init_sequence[i + 1], j,
1040                                           "init: write(0x%02X)", par->init_sequence[i]);
1041
1042                         /* Write */
1043                         j = 0;
1044                         while (par->init_sequence[i] >= 0) {
1045                                 if (j > 63) {
1046                                         dev_err(par->info->device,
1047                                                 "%s: Maximum register values exceeded\n",
1048                                                 __func__);
1049                                         return -EINVAL;
1050                                 }
1051                                 buf[j++] = par->init_sequence[i++];
1052                         }
1053                         par->fbtftops.write_register(par, j,
1054                                 buf[0], buf[1], buf[2], buf[3],
1055                                 buf[4], buf[5], buf[6], buf[7],
1056                                 buf[8], buf[9], buf[10], buf[11],
1057                                 buf[12], buf[13], buf[14], buf[15],
1058                                 buf[16], buf[17], buf[18], buf[19],
1059                                 buf[20], buf[21], buf[22], buf[23],
1060                                 buf[24], buf[25], buf[26], buf[27],
1061                                 buf[28], buf[29], buf[30], buf[31],
1062                                 buf[32], buf[33], buf[34], buf[35],
1063                                 buf[36], buf[37], buf[38], buf[39],
1064                                 buf[40], buf[41], buf[42], buf[43],
1065                                 buf[44], buf[45], buf[46], buf[47],
1066                                 buf[48], buf[49], buf[50], buf[51],
1067                                 buf[52], buf[53], buf[54], buf[55],
1068                                 buf[56], buf[57], buf[58], buf[59],
1069                                 buf[60], buf[61], buf[62], buf[63]);
1070                         break;
1071                 case -2:
1072                         i++;
1073                         fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
1074                                       "init: mdelay(%d)\n",
1075                                       par->init_sequence[i]);
1076                         mdelay(par->init_sequence[i++]);
1077                         break;
1078                 default:
1079                         dev_err(par->info->device,
1080                                 "unknown delimiter %d at position %d\n",
1081                                 par->init_sequence[i], i);
1082                         return -EINVAL;
1083                 }
1084         }
1085
1086         dev_err(par->info->device,
1087                 "%s: something is wrong. Shouldn't get here.\n", __func__);
1088         return -EINVAL;
1089 }
1090 EXPORT_SYMBOL(fbtft_init_display);
1091
1092 /**
1093  * fbtft_verify_gpios() - Generic verify_gpios() function
1094  * @par: Driver data
1095  *
1096  * Uses @spi, @pdev and @buswidth to determine which GPIOs is needed
1097  *
1098  * Return: 0 if successful, negative if error
1099  */
1100 static int fbtft_verify_gpios(struct fbtft_par *par)
1101 {
1102         struct fbtft_platform_data *pdata = par->pdata;
1103         int i;
1104
1105         fbtft_par_dbg(DEBUG_VERIFY_GPIOS, par, "%s()\n", __func__);
1106
1107         if (pdata->display.buswidth != 9 &&  par->startbyte == 0 &&
1108             !par->gpio.dc) {
1109                 dev_err(par->info->device,
1110                         "Missing info about 'dc' gpio. Aborting.\n");
1111                 return -EINVAL;
1112         }
1113
1114         if (!par->pdev)
1115                 return 0;
1116
1117         if (!par->gpio.wr) {
1118                 dev_err(par->info->device, "Missing 'wr' gpio. Aborting.\n");
1119                 return -EINVAL;
1120         }
1121         for (i = 0; i < pdata->display.buswidth; i++) {
1122                 if (!par->gpio.db[i]) {
1123                         dev_err(par->info->device,
1124                                 "Missing 'db%02d' gpio. Aborting.\n", i);
1125                         return -EINVAL;
1126                 }
1127         }
1128
1129         return 0;
1130 }
1131
1132 /* returns 0 if the property is not present */
1133 static u32 fbtft_property_value(struct device *dev, const char *propname)
1134 {
1135         int ret;
1136         u32 val = 0;
1137
1138         ret = device_property_read_u32(dev, propname, &val);
1139         if (ret == 0)
1140                 dev_info(dev, "%s: %s = %u\n", __func__, propname, val);
1141
1142         return val;
1143 }
1144
1145 static struct fbtft_platform_data *fbtft_properties_read(struct device *dev)
1146 {
1147         struct fbtft_platform_data *pdata;
1148
1149         if (!dev_fwnode(dev)) {
1150                 dev_err(dev, "Missing platform data or properties\n");
1151                 return ERR_PTR(-EINVAL);
1152         }
1153
1154         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
1155         if (!pdata)
1156                 return ERR_PTR(-ENOMEM);
1157
1158         pdata->display.width = fbtft_property_value(dev, "width");
1159         pdata->display.height = fbtft_property_value(dev, "height");
1160         pdata->display.regwidth = fbtft_property_value(dev, "regwidth");
1161         pdata->display.buswidth = fbtft_property_value(dev, "buswidth");
1162         pdata->display.backlight = fbtft_property_value(dev, "backlight");
1163         pdata->display.bpp = fbtft_property_value(dev, "bpp");
1164         pdata->display.debug = fbtft_property_value(dev, "debug");
1165         pdata->rotate = fbtft_property_value(dev, "rotate");
1166         pdata->bgr = device_property_read_bool(dev, "bgr");
1167         pdata->fps = fbtft_property_value(dev, "fps");
1168         pdata->txbuflen = fbtft_property_value(dev, "txbuflen");
1169         pdata->startbyte = fbtft_property_value(dev, "startbyte");
1170         device_property_read_string(dev, "gamma", (const char **)&pdata->gamma);
1171
1172         if (device_property_present(dev, "led-gpios"))
1173                 pdata->display.backlight = 1;
1174         if (device_property_present(dev, "init"))
1175                 pdata->display.fbtftops.init_display =
1176                         fbtft_init_display_from_property;
1177
1178         pdata->display.fbtftops.request_gpios = fbtft_request_gpios;
1179
1180         return pdata;
1181 }
1182
1183 /**
1184  * fbtft_probe_common() - Generic device probe() helper function
1185  * @display: Display properties
1186  * @sdev: SPI device
1187  * @pdev: Platform device
1188  *
1189  * Allocates, initializes and registers a framebuffer
1190  *
1191  * Either @sdev or @pdev should be NULL
1192  *
1193  * Return: 0 if successful, negative if error
1194  */
1195 int fbtft_probe_common(struct fbtft_display *display,
1196                        struct spi_device *sdev,
1197                        struct platform_device *pdev)
1198 {
1199         struct device *dev;
1200         struct fb_info *info;
1201         struct fbtft_par *par;
1202         struct fbtft_platform_data *pdata;
1203         int ret;
1204
1205         if (sdev)
1206                 dev = &sdev->dev;
1207         else
1208                 dev = &pdev->dev;
1209
1210         if (unlikely(display->debug & DEBUG_DRIVER_INIT_FUNCTIONS))
1211                 dev_info(dev, "%s()\n", __func__);
1212
1213         pdata = dev->platform_data;
1214         if (!pdata) {
1215                 pdata = fbtft_properties_read(dev);
1216                 if (IS_ERR(pdata))
1217                         return PTR_ERR(pdata);
1218         }
1219
1220         info = fbtft_framebuffer_alloc(display, dev, pdata);
1221         if (!info)
1222                 return -ENOMEM;
1223
1224         par = info->par;
1225         par->spi = sdev;
1226         par->pdev = pdev;
1227
1228         if (display->buswidth == 0) {
1229                 dev_err(dev, "buswidth is not set\n");
1230                 return -EINVAL;
1231         }
1232
1233         /* write register functions */
1234         if (display->regwidth == 8 && display->buswidth == 8)
1235                 par->fbtftops.write_register = fbtft_write_reg8_bus8;
1236         else if (display->regwidth == 8 && display->buswidth == 9 && par->spi)
1237                 par->fbtftops.write_register = fbtft_write_reg8_bus9;
1238         else if (display->regwidth == 16 && display->buswidth == 8)
1239                 par->fbtftops.write_register = fbtft_write_reg16_bus8;
1240         else if (display->regwidth == 16 && display->buswidth == 16)
1241                 par->fbtftops.write_register = fbtft_write_reg16_bus16;
1242         else
1243                 dev_warn(dev,
1244                          "no default functions for regwidth=%d and buswidth=%d\n",
1245                          display->regwidth, display->buswidth);
1246
1247         /* write_vmem() functions */
1248         if (display->buswidth == 8)
1249                 par->fbtftops.write_vmem = fbtft_write_vmem16_bus8;
1250         else if (display->buswidth == 9)
1251                 par->fbtftops.write_vmem = fbtft_write_vmem16_bus9;
1252         else if (display->buswidth == 16)
1253                 par->fbtftops.write_vmem = fbtft_write_vmem16_bus16;
1254
1255         /* GPIO write() functions */
1256         if (par->pdev) {
1257                 if (display->buswidth == 8)
1258                         par->fbtftops.write = fbtft_write_gpio8_wr;
1259                 else if (display->buswidth == 16)
1260                         par->fbtftops.write = fbtft_write_gpio16_wr;
1261         }
1262
1263         /* 9-bit SPI setup */
1264         if (par->spi && display->buswidth == 9) {
1265                 if (par->spi->master->bits_per_word_mask & SPI_BPW_MASK(9)) {
1266                         par->spi->bits_per_word = 9;
1267                 } else {
1268                         dev_warn(&par->spi->dev,
1269                                  "9-bit SPI not available, emulating using 8-bit.\n");
1270                         /* allocate buffer with room for dc bits */
1271                         par->extra = devm_kzalloc(par->info->device,
1272                                                   par->txbuf.len +
1273                                                   (par->txbuf.len / 8) + 8,
1274                                                   GFP_KERNEL);
1275                         if (!par->extra) {
1276                                 ret = -ENOMEM;
1277                                 goto out_release;
1278                         }
1279                         par->fbtftops.write = fbtft_write_spi_emulate_9;
1280                 }
1281         }
1282
1283         if (!par->fbtftops.verify_gpios)
1284                 par->fbtftops.verify_gpios = fbtft_verify_gpios;
1285
1286         /* make sure we still use the driver provided functions */
1287         fbtft_merge_fbtftops(&par->fbtftops, &display->fbtftops);
1288
1289         /* use init_sequence if provided */
1290         if (par->init_sequence)
1291                 par->fbtftops.init_display = fbtft_init_display;
1292
1293         /* use platform_data provided functions above all */
1294         fbtft_merge_fbtftops(&par->fbtftops, &pdata->display.fbtftops);
1295
1296         ret = fbtft_register_framebuffer(info);
1297         if (ret < 0)
1298                 goto out_release;
1299
1300         return 0;
1301
1302 out_release:
1303         fbtft_framebuffer_release(info);
1304
1305         return ret;
1306 }
1307 EXPORT_SYMBOL(fbtft_probe_common);
1308
1309 /**
1310  * fbtft_remove_common() - Generic device remove() helper function
1311  * @dev: Device
1312  * @info: Framebuffer
1313  *
1314  * Unregisters and releases the framebuffer
1315  */
1316 void fbtft_remove_common(struct device *dev, struct fb_info *info)
1317 {
1318         struct fbtft_par *par;
1319
1320         par = info->par;
1321         if (par)
1322                 fbtft_par_dbg(DEBUG_DRIVER_INIT_FUNCTIONS, par,
1323                               "%s()\n", __func__);
1324         fbtft_unregister_framebuffer(info);
1325         fbtft_framebuffer_release(info);
1326 }
1327 EXPORT_SYMBOL(fbtft_remove_common);
1328
1329 MODULE_LICENSE("GPL");