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/spinlock.h>
  26 #include <linux/of.h>
  27 #include <video/mipi_display.h>
  28
  29 #include "fbtft.h"
  30 #include "internal.h"
  31
  32 static unsigned long debug;
  33 module_param(debug, ulong, 0000);
  34 MODULE_PARM_DESC(debug, "override device debug level");
  35
  36 int fbtft_write_buf_dc(struct fbtft_par *par, void *buf, size_t len, int dc)
  37 {
  38         int ret;
  39
  40         if (par->gpio.dc)
  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                    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 #ifdef CONFIG_OF
  74 static int fbtft_request_one_gpio(struct fbtft_par *par,
  75                                   const char *name, int index,
  76                                   struct gpio_desc **gpiop)
  77 {
  78         struct device *dev = par->info->device;
  79         int ret = 0;
  80
  81         *gpiop = devm_gpiod_get_index_optional(dev, name, index,
  82                                                GPIOD_OUT_HIGH);
  83         if (IS_ERR(*gpiop)) {
  84                 ret = PTR_ERR(*gpiop);
  85                 dev_err(dev,
  86                         "Failed to request %s GPIO: %d\n", name, ret);
  87                 return ret;
  88         }
  89         fbtft_par_dbg(DEBUG_REQUEST_GPIOS, par, "%s: '%s' GPIO\n",
  90                       __func__, name);
  91
  92         return ret;
  93 }
  94
  95 static int fbtft_request_gpios_dt(struct fbtft_par *par)
  96 {
  97         int i;
  98         int ret;
  99
 100         if (!par->info->device->of_node)
 101                 return -EINVAL;
 102
 103         ret = fbtft_request_one_gpio(par, "reset", 0, &par->gpio.reset);
 104         if (ret)
 105                 return ret;
 106         ret = fbtft_request_one_gpio(par, "dc", 0, &par->gpio.dc);
 107         if (ret)
 108                 return ret;
 109         ret = fbtft_request_one_gpio(par, "rd", 0, &par->gpio.rd);
 110         if (ret)
 111                 return ret;
 112         ret = fbtft_request_one_gpio(par, "wr", 0, &par->gpio.wr);
 113         if (ret)
 114                 return ret;
 115         ret = fbtft_request_one_gpio(par, "cs", 0, &par->gpio.cs);
 116         if (ret)
 117                 return ret;
 118         ret = fbtft_request_one_gpio(par, "latch", 0, &par->gpio.latch);
 119         if (ret)
 120                 return ret;
 121         for (i = 0; i < 16; i++) {
 122                 ret = fbtft_request_one_gpio(par, "db", i,
 123                                              &par->gpio.db[i]);
 124                 if (ret)
 125                         return ret;
 126                 ret = fbtft_request_one_gpio(par, "led", i,
 127                                              &par->gpio.led[i]);
 128                 if (ret)
 129                         return ret;
 130                 ret = fbtft_request_one_gpio(par, "aux", i,
 131                                              &par->gpio.aux[i]);
 132                 if (ret)
 133                         return ret;
 134         }
 135
 136         return 0;
 137 }
 138 #endif
 139
 140 #ifdef CONFIG_FB_BACKLIGHT
 141 static int fbtft_backlight_update_status(struct backlight_device *bd)
 142 {
 143         struct fbtft_par *par = bl_get_data(bd);
 144         bool polarity = par->polarity;
 145
 146         fbtft_par_dbg(DEBUG_BACKLIGHT, par,
 147                       "%s: polarity=%d, power=%d, fb_blank=%d\n",
 148                       __func__, polarity, bd->props.power, bd->props.fb_blank);
 149
 150         if ((bd->props.power == FB_BLANK_UNBLANK) &&
 151             (bd->props.fb_blank == FB_BLANK_UNBLANK))
 152                 gpiod_set_value(par->gpio.led[0], polarity);
 153         else
 154                 gpiod_set_value(par->gpio.led[0], !polarity);
 155
 156         return 0;
 157 }
 158
 159 static int fbtft_backlight_get_brightness(struct backlight_device *bd)
 160 {
 161         return bd->props.brightness;
 162 }
 163
 164 void fbtft_unregister_backlight(struct fbtft_par *par)
 165 {
 166         if (par->info->bl_dev) {
 167                 par->info->bl_dev->props.power = FB_BLANK_POWERDOWN;
 168                 backlight_update_status(par->info->bl_dev);
 169                 backlight_device_unregister(par->info->bl_dev);
 170                 par->info->bl_dev = NULL;
 171         }
 172 }
 173
 174 static const struct backlight_ops fbtft_bl_ops = {
 175         .get_brightness = fbtft_backlight_get_brightness,
 176         .update_status  = fbtft_backlight_update_status,
 177 };
 178
 179 void fbtft_register_backlight(struct fbtft_par *par)
 180 {
 181         struct backlight_device *bd;
 182         struct backlight_properties bl_props = { 0, };
 183
 184         if (!par->gpio.led[0]) {
 185                 fbtft_par_dbg(DEBUG_BACKLIGHT, par,
 186                               "%s(): led pin not set, exiting.\n", __func__);
 187                 return;
 188         }
 189
 190         bl_props.type = BACKLIGHT_RAW;
 191         /* Assume backlight is off, get polarity from current state of pin */
 192         bl_props.power = FB_BLANK_POWERDOWN;
 193         if (!gpiod_get_value(par->gpio.led[0]))
 194                 par->polarity = true;
 195
 196         bd = backlight_device_register(dev_driver_string(par->info->device),
 197                                        par->info->device, par,
 198                                        &fbtft_bl_ops, &bl_props);
 199         if (IS_ERR(bd)) {
 200                 dev_err(par->info->device,
 201                         "cannot register backlight device (%ld)\n",
 202                         PTR_ERR(bd));
 203                 return;
 204         }
 205         par->info->bl_dev = bd;
 206
 207         if (!par->fbtftops.unregister_backlight)
 208                 par->fbtftops.unregister_backlight = fbtft_unregister_backlight;
 209 }
 210 #else
 211 void fbtft_register_backlight(struct fbtft_par *par) { };
 212 void fbtft_unregister_backlight(struct fbtft_par *par) { };
 213 #endif
 214 EXPORT_SYMBOL(fbtft_register_backlight);
 215 EXPORT_SYMBOL(fbtft_unregister_backlight);
 216
 217 static void fbtft_set_addr_win(struct fbtft_par *par, int xs, int ys, int xe,
 218                                int ye)
 219 {
 220         write_reg(par, MIPI_DCS_SET_COLUMN_ADDRESS,
 221                   (xs >> 8) & 0xFF, xs & 0xFF, (xe >> 8) & 0xFF, xe & 0xFF);
 222
 223         write_reg(par, MIPI_DCS_SET_PAGE_ADDRESS,
 224                   (ys >> 8) & 0xFF, ys & 0xFF, (ye >> 8) & 0xFF, ye & 0xFF);
 225
 226         write_reg(par, MIPI_DCS_WRITE_MEMORY_START);
 227 }
 228
 229 static void fbtft_reset(struct fbtft_par *par)
 230 {
 231         if (!par->gpio.reset)
 232                 return;
 233         fbtft_par_dbg(DEBUG_RESET, par, "%s()\n", __func__);
 234         gpiod_set_value_cansleep(par->gpio.reset, 1);
 235         usleep_range(20, 40);
 236         gpiod_set_value_cansleep(par->gpio.reset, 0);
 237         msleep(120);
 238 }
 239
 240 static void fbtft_update_display(struct fbtft_par *par, unsigned int start_line,
 241                                  unsigned int end_line)
 242 {
 243         size_t offset, len;
 244         ktime_t ts_start, ts_end;
 245         long fps, throughput;
 246         bool timeit = false;
 247         int ret = 0;
 248
 249         if (unlikely(par->debug & (DEBUG_TIME_FIRST_UPDATE |
 250                         DEBUG_TIME_EACH_UPDATE))) {
 251                 if ((par->debug & DEBUG_TIME_EACH_UPDATE) ||
 252                     ((par->debug & DEBUG_TIME_FIRST_UPDATE) &&
 253                     !par->first_update_done)) {
 254                         ts_start = ktime_get();
 255                         timeit = true;
 256                 }
 257         }
 258
 259         /* Sanity checks */
 260         if (start_line > end_line) {
 261                 dev_warn(par->info->device,
 262                          "%s: start_line=%u is larger than end_line=%u. Shouldn't happen, will do full display update\n",
 263                          __func__, start_line, end_line);
 264                 start_line = 0;
 265                 end_line = par->info->var.yres - 1;
 266         }
 267         if (start_line > par->info->var.yres - 1 ||
 268             end_line > par->info->var.yres - 1) {
 269                 dev_warn(par->info->device,
 270                          "%s: start_line=%u or end_line=%u is larger than max=%d. Shouldn't happen, will do full display update\n",
 271                          __func__, start_line,
 272                          end_line, par->info->var.yres - 1);
 273                 start_line = 0;
 274                 end_line = par->info->var.yres - 1;
 275         }
 276
 277         fbtft_par_dbg(DEBUG_UPDATE_DISPLAY, par, "%s(start_line=%u, end_line=%u)\n",
 278                       __func__, start_line, end_line);
 279
 280         if (par->fbtftops.set_addr_win)
 281                 par->fbtftops.set_addr_win(par, 0, start_line,
 282                                 par->info->var.xres - 1, end_line);
 283
 284         offset = start_line * par->info->fix.line_length;
 285         len = (end_line - start_line + 1) * par->info->fix.line_length;
 286         ret = par->fbtftops.write_vmem(par, offset, len);
 287         if (ret < 0)
 288                 dev_err(par->info->device,
 289                         "%s: write_vmem failed to update display buffer\n",
 290                         __func__);
 291
 292         if (unlikely(timeit)) {
 293                 ts_end = ktime_get();
 294                 if (!ktime_to_ns(par->update_time))
 295                         par->update_time = ts_start;
 296
 297                 fps = ktime_us_delta(ts_start, par->update_time);
 298                 par->update_time = ts_start;
 299                 fps = fps ? 1000000 / fps : 0;
 300
 301                 throughput = ktime_us_delta(ts_end, ts_start);
 302                 throughput = throughput ? (len * 1000) / throughput : 0;
 303                 throughput = throughput * 1000 / 1024;
 304
 305                 dev_info(par->info->device,
 306                          "Display update: %ld kB/s, fps=%ld\n",
 307                          throughput, fps);
 308                 par->first_update_done = true;
 309         }
 310 }
 311
 312 static void fbtft_mkdirty(struct fb_info *info, int y, int height)
 313 {
 314         struct fbtft_par *par = info->par;
 315         struct fb_deferred_io *fbdefio = info->fbdefio;
 316
 317         /* special case, needed ? */
 318         if (y == -1) {
 319                 y = 0;
 320                 height = info->var.yres - 1;
 321         }
 322
 323         /* Mark display lines/area as dirty */
 324         spin_lock(&par->dirty_lock);
 325         if (y < par->dirty_lines_start)
 326                 par->dirty_lines_start = y;
 327         if (y + height - 1 > par->dirty_lines_end)
 328                 par->dirty_lines_end = y + height - 1;
 329         spin_unlock(&par->dirty_lock);
 330
 331         /* Schedule deferred_io to update display (no-op if already on queue)*/
 332         schedule_delayed_work(&info->deferred_work, fbdefio->delay);
 333 }
 334
 335 static void fbtft_deferred_io(struct fb_info *info, struct list_head *pagelist)
 336 {
 337         struct fbtft_par *par = info->par;
 338         unsigned int dirty_lines_start, dirty_lines_end;
 339         struct page *page;
 340         unsigned long index;
 341         unsigned int y_low = 0, y_high = 0;
 342         int count = 0;
 343
 344         spin_lock(&par->dirty_lock);
 345         dirty_lines_start = par->dirty_lines_start;
 346         dirty_lines_end = par->dirty_lines_end;
 347         /* set display line markers as clean */
 348         par->dirty_lines_start = par->info->var.yres - 1;
 349         par->dirty_lines_end = 0;
 350         spin_unlock(&par->dirty_lock);
 351
 352         /* Mark display lines as dirty */
 353         list_for_each_entry(page, pagelist, lru) {
 354                 count++;
 355                 index = page->index << PAGE_SHIFT;
 356                 y_low = index / info->fix.line_length;
 357                 y_high = (index + PAGE_SIZE - 1) / info->fix.line_length;
 358                 dev_dbg(info->device,
 359                         "page->index=%lu y_low=%d y_high=%d\n",
 360                         page->index, y_low, y_high);
 361                 if (y_high > info->var.yres - 1)
 362                         y_high = info->var.yres - 1;
 363                 if (y_low < dirty_lines_start)
 364                         dirty_lines_start = y_low;
 365                 if (y_high > dirty_lines_end)
 366                         dirty_lines_end = y_high;
 367         }
 368
 369         par->fbtftops.update_display(info->par,
 370                                         dirty_lines_start, dirty_lines_end);
 371 }
 372
 373 static void fbtft_fb_fillrect(struct fb_info *info,
 374                               const struct fb_fillrect *rect)
 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__, rect->dx, rect->dy, rect->width, rect->height);
 381         sys_fillrect(info, rect);
 382
 383         par->fbtftops.mkdirty(info, rect->dy, rect->height);
 384 }
 385
 386 static void fbtft_fb_copyarea(struct fb_info *info,
 387                               const struct fb_copyarea *area)
 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__,  area->dx, area->dy, area->width, area->height);
 394         sys_copyarea(info, area);
 395
 396         par->fbtftops.mkdirty(info, area->dy, area->height);
 397 }
 398
 399 static void fbtft_fb_imageblit(struct fb_info *info,
 400                                const struct fb_image *image)
 401 {
 402         struct fbtft_par *par = info->par;
 403
 404         dev_dbg(info->dev,
 405                 "%s: dx=%d, dy=%d, width=%d, height=%d\n",
 406                 __func__,  image->dx, image->dy, image->width, image->height);
 407         sys_imageblit(info, image);
 408
 409         par->fbtftops.mkdirty(info, image->dy, image->height);
 410 }
 411
 412 static ssize_t fbtft_fb_write(struct fb_info *info, const char __user *buf,
 413                               size_t count, loff_t *ppos)
 414 {
 415         struct fbtft_par *par = info->par;
 416         ssize_t res;
 417
 418         dev_dbg(info->dev,
 419                 "%s: count=%zd, ppos=%llu\n", __func__,  count, *ppos);
 420         res = fb_sys_write(info, buf, count, ppos);
 421
 422         /* TODO: only mark changed area update all for now */
 423         par->fbtftops.mkdirty(info, -1, 0);
 424
 425         return res;
 426 }
 427
 428 /* from pxafb.c */
 429 static unsigned int chan_to_field(unsigned int chan, struct fb_bitfield *bf)
 430 {
 431         chan &= 0xffff;
 432         chan >>= 16 - bf->length;
 433         return chan << bf->offset;
 434 }
 435
 436 static int fbtft_fb_setcolreg(unsigned int regno, unsigned int red,
 437                               unsigned int green, unsigned int blue,
 438                               unsigned int transp, struct fb_info *info)
 439 {
 440         unsigned int val;
 441         int ret = 1;
 442
 443         dev_dbg(info->dev,
 444                 "%s(regno=%u, red=0x%X, green=0x%X, blue=0x%X, trans=0x%X)\n",
 445                 __func__, regno, red, green, blue, transp);
 446
 447         switch (info->fix.visual) {
 448         case FB_VISUAL_TRUECOLOR:
 449                 if (regno < 16) {
 450                         u32 *pal = info->pseudo_palette;
 451
 452                         val  = chan_to_field(red,   &info->var.red);
 453                         val |= chan_to_field(green, &info->var.green);
 454                         val |= chan_to_field(blue,  &info->var.blue);
 455
 456                         pal[regno] = val;
 457                         ret = 0;
 458                 }
 459                 break;
 460         }
 461         return ret;
 462 }
 463
 464 static int fbtft_fb_blank(int blank, struct fb_info *info)
 465 {
 466         struct fbtft_par *par = info->par;
 467         int ret = -EINVAL;
 468
 469         dev_dbg(info->dev, "%s(blank=%d)\n",
 470                 __func__, blank);
 471
 472         if (!par->fbtftops.blank)
 473                 return ret;
 474
 475         switch (blank) {
 476         case FB_BLANK_POWERDOWN:
 477         case FB_BLANK_VSYNC_SUSPEND:
 478         case FB_BLANK_HSYNC_SUSPEND:
 479         case FB_BLANK_NORMAL:
 480                 ret = par->fbtftops.blank(par, true);
 481                 break;
 482         case FB_BLANK_UNBLANK:
 483                 ret = par->fbtftops.blank(par, false);
 484                 break;
 485         }
 486         return ret;
 487 }
 488
 489 static void fbtft_merge_fbtftops(struct fbtft_ops *dst, struct fbtft_ops *src)
 490 {
 491         if (src->write)
 492                 dst->write = src->write;
 493         if (src->read)
 494                 dst->read = src->read;
 495         if (src->write_vmem)
 496                 dst->write_vmem = src->write_vmem;
 497         if (src->write_register)
 498                 dst->write_register = src->write_register;
 499         if (src->set_addr_win)
 500                 dst->set_addr_win = src->set_addr_win;
 501         if (src->reset)
 502                 dst->reset = src->reset;
 503         if (src->mkdirty)
 504                 dst->mkdirty = src->mkdirty;
 505         if (src->update_display)
 506                 dst->update_display = src->update_display;
 507         if (src->init_display)
 508                 dst->init_display = src->init_display;
 509         if (src->blank)
 510                 dst->blank = src->blank;
 511         if (src->request_gpios_match)
 512                 dst->request_gpios_match = src->request_gpios_match;
 513         if (src->request_gpios)
 514                 dst->request_gpios = src->request_gpios;
 515         if (src->verify_gpios)
 516                 dst->verify_gpios = src->verify_gpios;
 517         if (src->register_backlight)
 518                 dst->register_backlight = src->register_backlight;
 519         if (src->unregister_backlight)
 520                 dst->unregister_backlight = src->unregister_backlight;
 521         if (src->set_var)
 522                 dst->set_var = src->set_var;
 523         if (src->set_gamma)
 524                 dst->set_gamma = src->set_gamma;
 525 }
 526
 527 /**
 528  * fbtft_framebuffer_alloc - creates a new frame buffer info structure
 529  *
 530  * @display: pointer to structure describing the display
 531  * @dev: pointer to the device for this fb, this can be NULL
 532  *
 533  * Creates a new frame buffer info structure.
 534  *
 535  * Also creates and populates the following structures:
 536  *   info->fbops
 537  *   info->fbdefio
 538  *   info->pseudo_palette
 539  *   par->fbtftops
 540  *   par->txbuf
 541  *
 542  * Returns the new structure, or NULL if an error occurred.
 543  *
 544  */
 545 struct fb_info *fbtft_framebuffer_alloc(struct fbtft_display *display,
 546                                         struct device *dev,
 547                                         struct fbtft_platform_data *pdata)
 548 {
 549         struct fb_info *info;
 550         struct fbtft_par *par;
 551         struct fb_ops *fbops = NULL;
 552         struct fb_deferred_io *fbdefio = NULL;
 553         u8 *vmem = NULL;
 554         void *txbuf = NULL;
 555         void *buf = NULL;
 556         unsigned int width;
 557         unsigned int height;
 558         int txbuflen = display->txbuflen;
 559         unsigned int bpp = display->bpp;
 560         unsigned int fps = display->fps;
 561         int vmem_size;
 562         const s16 *init_sequence = display->init_sequence;
 563         char *gamma = display->gamma;
 564         u32 *gamma_curves = NULL;
 565
 566         /* sanity check */
 567         if (display->gamma_num * display->gamma_len >
 568                         FBTFT_GAMMA_MAX_VALUES_TOTAL) {
 569                 dev_err(dev, "FBTFT_GAMMA_MAX_VALUES_TOTAL=%d is exceeded\n",
 570                         FBTFT_GAMMA_MAX_VALUES_TOTAL);
 571                 return NULL;
 572         }
 573
 574         /* defaults */
 575         if (!fps)
 576                 fps = 20;
 577         if (!bpp)
 578                 bpp = 16;
 579
 580         if (!pdata) {
 581                 dev_err(dev, "platform data is missing\n");
 582                 return NULL;
 583         }
 584
 585         /* override driver values? */
 586         if (pdata->fps)
 587                 fps = pdata->fps;
 588         if (pdata->txbuflen)
 589                 txbuflen = pdata->txbuflen;
 590         if (pdata->display.init_sequence)
 591                 init_sequence = pdata->display.init_sequence;
 592         if (pdata->gamma)
 593                 gamma = pdata->gamma;
 594         if (pdata->display.debug)
 595                 display->debug = pdata->display.debug;
 596         if (pdata->display.backlight)
 597                 display->backlight = pdata->display.backlight;
 598         if (pdata->display.width)
 599                 display->width = pdata->display.width;
 600         if (pdata->display.height)
 601                 display->height = pdata->display.height;
 602         if (pdata->display.buswidth)
 603                 display->buswidth = pdata->display.buswidth;
 604         if (pdata->display.regwidth)
 605                 display->regwidth = pdata->display.regwidth;
 606
 607         display->debug |= debug;
 608         fbtft_expand_debug_value(&display->debug);
 609
 610         switch (pdata->rotate) {
 611         case 90:
 612         case 270:
 613                 width =  display->height;
 614                 height = display->width;
 615                 break;
 616         default:
 617                 width =  display->width;
 618                 height = display->height;
 619         }
 620
 621         vmem_size = display->width * display->height * bpp / 8;
 622         vmem = vzalloc(vmem_size);
 623         if (!vmem)
 624                 goto alloc_fail;
 625
 626         fbops = devm_kzalloc(dev, sizeof(struct fb_ops), GFP_KERNEL);
 627         if (!fbops)
 628                 goto alloc_fail;
 629
 630         fbdefio = devm_kzalloc(dev, sizeof(struct fb_deferred_io), GFP_KERNEL);
 631         if (!fbdefio)
 632                 goto alloc_fail;
 633
 634         buf = devm_kzalloc(dev, 128, GFP_KERNEL);
 635         if (!buf)
 636                 goto alloc_fail;
 637
 638         if (display->gamma_num && display->gamma_len) {
 639                 gamma_curves = devm_kcalloc(dev,
 640                                             display->gamma_num *
 641                                             display->gamma_len,
 642                                             sizeof(gamma_curves[0]),
 643                                             GFP_KERNEL);
 644                 if (!gamma_curves)
 645                         goto alloc_fail;
 646         }
 647
 648         info = framebuffer_alloc(sizeof(struct fbtft_par), dev);
 649         if (!info)
 650                 goto alloc_fail;
 651
 652         info->screen_buffer = vmem;
 653         info->fbops = fbops;
 654         info->fbdefio = fbdefio;
 655
 656         fbops->owner        =      dev->driver->owner;
 657         fbops->fb_read      =      fb_sys_read;
 658         fbops->fb_write     =      fbtft_fb_write;
 659         fbops->fb_fillrect  =      fbtft_fb_fillrect;
 660         fbops->fb_copyarea  =      fbtft_fb_copyarea;
 661         fbops->fb_imageblit =      fbtft_fb_imageblit;
 662         fbops->fb_setcolreg =      fbtft_fb_setcolreg;
 663         fbops->fb_blank     =      fbtft_fb_blank;
 664
 665         fbdefio->delay =           HZ / fps;
 666         fbdefio->deferred_io =     fbtft_deferred_io;
 667         fb_deferred_io_init(info);
 668
 669         strncpy(info->fix.id, dev->driver->name, 16);
 670         info->fix.type =           FB_TYPE_PACKED_PIXELS;
 671         info->fix.visual =         FB_VISUAL_TRUECOLOR;
 672         info->fix.xpanstep =       0;
 673         info->fix.ypanstep =       0;
 674         info->fix.ywrapstep =      0;
 675         info->fix.line_length =    width * bpp / 8;
 676         info->fix.accel =          FB_ACCEL_NONE;
 677         info->fix.smem_len =       vmem_size;
 678
 679         info->var.rotate =         pdata->rotate;
 680         info->var.xres =           width;
 681         info->var.yres =           height;
 682         info->var.xres_virtual =   info->var.xres;
 683         info->var.yres_virtual =   info->var.yres;
 684         info->var.bits_per_pixel = bpp;
 685         info->var.nonstd =         1;
 686
 687         /* RGB565 */
 688         info->var.red.offset =     11;
 689         info->var.red.length =     5;
 690         info->var.green.offset =   5;
 691         info->var.green.length =   6;
 692         info->var.blue.offset =    0;
 693         info->var.blue.length =    5;
 694         info->var.transp.offset =  0;
 695         info->var.transp.length =  0;
 696
 697         info->flags =              FBINFO_FLAG_DEFAULT | FBINFO_VIRTFB;
 698
 699         par = info->par;
 700         par->info = info;
 701         par->pdata = pdata;
 702         par->debug = display->debug;
 703         par->buf = buf;
 704         spin_lock_init(&par->dirty_lock);
 705         par->bgr = pdata->bgr;
 706         par->startbyte = pdata->startbyte;
 707         par->init_sequence = init_sequence;
 708         par->gamma.curves = gamma_curves;
 709         par->gamma.num_curves = display->gamma_num;
 710         par->gamma.num_values = display->gamma_len;
 711         mutex_init(&par->gamma.lock);
 712         info->pseudo_palette = par->pseudo_palette;
 713
 714         if (par->gamma.curves && gamma) {
 715                 if (fbtft_gamma_parse_str(par, par->gamma.curves, gamma,
 716                                           strlen(gamma)))
 717                         goto alloc_fail;
 718         }
 719
 720         /* Transmit buffer */
 721         if (txbuflen == -1)
 722                 txbuflen = vmem_size + 2; /* add in case startbyte is used */
 723         if (txbuflen >= vmem_size + 2)
 724                 txbuflen = 0;
 725
 726 #ifdef __LITTLE_ENDIAN
 727         if ((!txbuflen) && (bpp > 8))
 728                 txbuflen = PAGE_SIZE; /* need buffer for byteswapping */
 729 #endif
 730
 731         if (txbuflen > 0) {
 732                 txbuf = devm_kzalloc(par->info->device, txbuflen, GFP_KERNEL);
 733                 if (!txbuf)
 734                         goto alloc_fail;
 735                 par->txbuf.buf = txbuf;
 736                 par->txbuf.len = txbuflen;
 737         }
 738
 739         /* default fbtft operations */
 740         par->fbtftops.write = fbtft_write_spi;
 741         par->fbtftops.read = fbtft_read_spi;
 742         par->fbtftops.write_vmem = fbtft_write_vmem16_bus8;
 743         par->fbtftops.write_register = fbtft_write_reg8_bus8;
 744         par->fbtftops.set_addr_win = fbtft_set_addr_win;
 745         par->fbtftops.reset = fbtft_reset;
 746         par->fbtftops.mkdirty = fbtft_mkdirty;
 747         par->fbtftops.update_display = fbtft_update_display;
 748         if (display->backlight)
 749                 par->fbtftops.register_backlight = fbtft_register_backlight;
 750
 751         /* use driver provided functions */
 752         fbtft_merge_fbtftops(&par->fbtftops, &display->fbtftops);
 753
 754         return info;
 755
 756 alloc_fail:
 757         vfree(vmem);
 758
 759         return NULL;
 760 }
 761 EXPORT_SYMBOL(fbtft_framebuffer_alloc);
 762
 763 /**
 764  * fbtft_framebuffer_release - frees up all memory used by the framebuffer
 765  *
 766  * @info: frame buffer info structure
 767  *
 768  */
 769 void fbtft_framebuffer_release(struct fb_info *info)
 770 {
 771         fb_deferred_io_cleanup(info);
 772         vfree(info->screen_buffer);
 773         framebuffer_release(info);
 774 }
 775 EXPORT_SYMBOL(fbtft_framebuffer_release);
 776
 777 /**
 778  *      fbtft_register_framebuffer - registers a tft frame buffer device
 779  *      @fb_info: frame buffer info structure
 780  *
 781  *  Sets SPI driverdata if needed
 782  *  Requests needed gpios.
 783  *  Initializes display
 784  *  Updates display.
 785  *      Registers a frame buffer device @fb_info.
 786  *
 787  *      Returns negative errno on error, or zero for success.
 788  *
 789  */
 790 int fbtft_register_framebuffer(struct fb_info *fb_info)
 791 {
 792         int ret;
 793         char text1[50] = "";
 794         char text2[50] = "";
 795         struct fbtft_par *par = fb_info->par;
 796         struct spi_device *spi = par->spi;
 797
 798         /* sanity checks */
 799         if (!par->fbtftops.init_display) {
 800                 dev_err(fb_info->device, "missing fbtftops.init_display()\n");
 801                 return -EINVAL;
 802         }
 803
 804         if (spi)
 805                 spi_set_drvdata(spi, fb_info);
 806         if (par->pdev)
 807                 platform_set_drvdata(par->pdev, fb_info);
 808
 809         ret = par->fbtftops.request_gpios(par);
 810         if (ret < 0)
 811                 goto reg_fail;
 812
 813         if (par->fbtftops.verify_gpios) {
 814                 ret = par->fbtftops.verify_gpios(par);
 815                 if (ret < 0)
 816                         goto reg_fail;
 817         }
 818
 819         ret = par->fbtftops.init_display(par);
 820         if (ret < 0)
 821                 goto reg_fail;
 822         if (par->fbtftops.set_var) {
 823                 ret = par->fbtftops.set_var(par);
 824                 if (ret < 0)
 825                         goto reg_fail;
 826         }
 827
 828         /* update the entire display */
 829         par->fbtftops.update_display(par, 0, par->info->var.yres - 1);
 830
 831         if (par->fbtftops.set_gamma && par->gamma.curves) {
 832                 ret = par->fbtftops.set_gamma(par, par->gamma.curves);
 833                 if (ret)
 834                         goto reg_fail;
 835         }
 836
 837         if (par->fbtftops.register_backlight)
 838                 par->fbtftops.register_backlight(par);
 839
 840         ret = register_framebuffer(fb_info);
 841         if (ret < 0)
 842                 goto reg_fail;
 843
 844         fbtft_sysfs_init(par);
 845
 846         if (par->txbuf.buf && par->txbuf.len >= 1024)
 847                 sprintf(text1, ", %zu KiB buffer memory", par->txbuf.len >> 10);
 848         if (spi)
 849                 sprintf(text2, ", spi%d.%d at %d MHz", spi->master->bus_num,
 850                         spi->chip_select, spi->max_speed_hz / 1000000);
 851         dev_info(fb_info->dev,
 852                  "%s frame buffer, %dx%d, %d KiB video memory%s, fps=%lu%s\n",
 853                  fb_info->fix.id, fb_info->var.xres, fb_info->var.yres,
 854                  fb_info->fix.smem_len >> 10, text1,
 855                  HZ / fb_info->fbdefio->delay, text2);
 856
 857 #ifdef CONFIG_FB_BACKLIGHT
 858         /* Turn on backlight if available */
 859         if (fb_info->bl_dev) {
 860                 fb_info->bl_dev->props.power = FB_BLANK_UNBLANK;
 861                 fb_info->bl_dev->ops->update_status(fb_info->bl_dev);
 862         }
 863 #endif
 864
 865         return 0;
 866
 867 reg_fail:
 868         if (par->fbtftops.unregister_backlight)
 869                 par->fbtftops.unregister_backlight(par);
 870
 871         return ret;
 872 }
 873 EXPORT_SYMBOL(fbtft_register_framebuffer);
 874
 875 /**
 876  *      fbtft_unregister_framebuffer - releases a tft frame buffer device
 877  *      @fb_info: frame buffer info structure
 878  *
 879  *  Frees SPI driverdata if needed
 880  *  Frees gpios.
 881  *      Unregisters frame buffer device.
 882  *
 883  */
 884 int fbtft_unregister_framebuffer(struct fb_info *fb_info)
 885 {
 886         struct fbtft_par *par = fb_info->par;
 887
 888         if (par->fbtftops.unregister_backlight)
 889                 par->fbtftops.unregister_backlight(par);
 890         fbtft_sysfs_exit(par);
 891         unregister_framebuffer(fb_info);
 892
 893         return 0;
 894 }
 895 EXPORT_SYMBOL(fbtft_unregister_framebuffer);
 896
 897 #ifdef CONFIG_OF
 898 /**
 899  * fbtft_init_display_dt() - Device Tree init_display() function
 900  * @par: Driver data
 901  *
 902  * Return: 0 if successful, negative if error
 903  */
 904 static int fbtft_init_display_dt(struct fbtft_par *par)
 905 {
 906         struct device_node *node = par->info->device->of_node;
 907         struct property *prop;
 908         const __be32 *p;
 909         u32 val;
 910         int buf[64], i, j;
 911
 912         if (!node)
 913                 return -EINVAL;
 914
 915         prop = of_find_property(node, "init", NULL);
 916         p = of_prop_next_u32(prop, NULL, &val);
 917         if (!p)
 918                 return -EINVAL;
 919
 920         par->fbtftops.reset(par);
 921         if (par->gpio.cs)
 922                 gpiod_set_value(par->gpio.cs, 0);  /* Activate chip */
 923
 924         while (p) {
 925                 if (val & FBTFT_OF_INIT_CMD) {
 926                         val &= 0xFFFF;
 927                         i = 0;
 928                         while (p && !(val & 0xFFFF0000)) {
 929                                 if (i > 63) {
 930                                         dev_err(par->info->device,
 931                                                 "%s: Maximum register values exceeded\n",
 932                                                 __func__);
 933                                         return -EINVAL;
 934                                 }
 935                                 buf[i++] = val;
 936                                 p = of_prop_next_u32(prop, p, &val);
 937                         }
 938                         /* make debug message */
 939                         fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
 940                                       "init: write_register:\n");
 941                         for (j = 0; j < i; j++)
 942                                 fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
 943                                               "buf[%d] = %02X\n", j, buf[j]);
 944
 945                         par->fbtftops.write_register(par, i,
 946                                 buf[0], buf[1], buf[2], buf[3],
 947                                 buf[4], buf[5], buf[6], buf[7],
 948                                 buf[8], buf[9], buf[10], buf[11],
 949                                 buf[12], buf[13], buf[14], buf[15],
 950                                 buf[16], buf[17], buf[18], buf[19],
 951                                 buf[20], buf[21], buf[22], buf[23],
 952                                 buf[24], buf[25], buf[26], buf[27],
 953                                 buf[28], buf[29], buf[30], buf[31],
 954                                 buf[32], buf[33], buf[34], buf[35],
 955                                 buf[36], buf[37], buf[38], buf[39],
 956                                 buf[40], buf[41], buf[42], buf[43],
 957                                 buf[44], buf[45], buf[46], buf[47],
 958                                 buf[48], buf[49], buf[50], buf[51],
 959                                 buf[52], buf[53], buf[54], buf[55],
 960                                 buf[56], buf[57], buf[58], buf[59],
 961                                 buf[60], buf[61], buf[62], buf[63]);
 962                 } else if (val & FBTFT_OF_INIT_DELAY) {
 963                         fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
 964                                       "init: msleep(%u)\n", val & 0xFFFF);
 965                         msleep(val & 0xFFFF);
 966                         p = of_prop_next_u32(prop, p, &val);
 967                 } else {
 968                         dev_err(par->info->device, "illegal init value 0x%X\n",
 969                                 val);
 970                         return -EINVAL;
 971                 }
 972         }
 973
 974         return 0;
 975 }
 976 #endif
 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         char msg[128];
 990         char str[16];
 991         int i = 0;
 992         int j;
 993
 994         /* sanity check */
 995         if (!par->init_sequence) {
 996                 dev_err(par->info->device,
 997                         "error: init_sequence is not set\n");
 998                 return -EINVAL;
 999         }
1000
1001         /* make sure stop marker exists */
1002         for (i = 0; i < FBTFT_MAX_INIT_SEQUENCE; i++)
1003                 if (par->init_sequence[i] == -3)
1004                         break;
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         if (par->gpio.cs)
1013                 gpiod_set_value(par->gpio.cs, 0);  /* Activate chip */
1014
1015         i = 0;
1016         while (i < FBTFT_MAX_INIT_SEQUENCE) {
1017                 if (par->init_sequence[i] == -3) {
1018                         /* done */
1019                         return 0;
1020                 }
1021                 if (par->init_sequence[i] >= 0) {
1022                         dev_err(par->info->device,
1023                                 "missing delimiter at position %d\n", i);
1024                         return -EINVAL;
1025                 }
1026                 if (par->init_sequence[i + 1] < 0) {
1027                         dev_err(par->info->device,
1028                                 "missing value after delimiter %d at position %d\n",
1029                                 par->init_sequence[i], i);
1030                         return -EINVAL;
1031                 }
1032                 switch (par->init_sequence[i]) {
1033                 case -1:
1034                         i++;
1035                         /* make debug message */
1036                         strcpy(msg, "");
1037                         j = i + 1;
1038                         while (par->init_sequence[j] >= 0) {
1039                                 sprintf(str, "0x%02X ", par->init_sequence[j]);
1040                                 strcat(msg, str);
1041                                 j++;
1042                         }
1043                         fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
1044                                       "init: write(0x%02X) %s\n",
1045                                       par->init_sequence[i], msg);
1046
1047                         /* Write */
1048                         j = 0;
1049                         while (par->init_sequence[i] >= 0) {
1050                                 if (j > 63) {
1051                                         dev_err(par->info->device,
1052                                                 "%s: Maximum register values exceeded\n",
1053                                                 __func__);
1054                                         return -EINVAL;
1055                                 }
1056                                 buf[j++] = par->init_sequence[i++];
1057                         }
1058                         par->fbtftops.write_register(par, j,
1059                                 buf[0], buf[1], buf[2], buf[3],
1060                                 buf[4], buf[5], buf[6], buf[7],
1061                                 buf[8], buf[9], buf[10], buf[11],
1062                                 buf[12], buf[13], buf[14], buf[15],
1063                                 buf[16], buf[17], buf[18], buf[19],
1064                                 buf[20], buf[21], buf[22], buf[23],
1065                                 buf[24], buf[25], buf[26], buf[27],
1066                                 buf[28], buf[29], buf[30], buf[31],
1067                                 buf[32], buf[33], buf[34], buf[35],
1068                                 buf[36], buf[37], buf[38], buf[39],
1069                                 buf[40], buf[41], buf[42], buf[43],
1070                                 buf[44], buf[45], buf[46], buf[47],
1071                                 buf[48], buf[49], buf[50], buf[51],
1072                                 buf[52], buf[53], buf[54], buf[55],
1073                                 buf[56], buf[57], buf[58], buf[59],
1074                                 buf[60], buf[61], buf[62], buf[63]);
1075                         break;
1076                 case -2:
1077                         i++;
1078                         fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
1079                                       "init: mdelay(%d)\n",
1080                                       par->init_sequence[i]);
1081                         mdelay(par->init_sequence[i++]);
1082                         break;
1083                 default:
1084                         dev_err(par->info->device,
1085                                 "unknown delimiter %d at position %d\n",
1086                                 par->init_sequence[i], i);
1087                         return -EINVAL;
1088                 }
1089         }
1090
1091         dev_err(par->info->device,
1092                 "%s: something is wrong. Shouldn't get here.\n", __func__);
1093         return -EINVAL;
1094 }
1095 EXPORT_SYMBOL(fbtft_init_display);
1096
1097 /**
1098  * fbtft_verify_gpios() - Generic verify_gpios() function
1099  * @par: Driver data
1100  *
1101  * Uses @spi, @pdev and @buswidth to determine which GPIOs is needed
1102  *
1103  * Return: 0 if successful, negative if error
1104  */
1105 static int fbtft_verify_gpios(struct fbtft_par *par)
1106 {
1107         struct fbtft_platform_data *pdata = par->pdata;
1108         int i;
1109
1110         fbtft_par_dbg(DEBUG_VERIFY_GPIOS, par, "%s()\n", __func__);
1111
1112         if (pdata->display.buswidth != 9 &&  par->startbyte == 0 &&
1113             !par->gpio.dc) {
1114                 dev_err(par->info->device,
1115                         "Missing info about 'dc' gpio. Aborting.\n");
1116                 return -EINVAL;
1117         }
1118
1119         if (!par->pdev)
1120                 return 0;
1121
1122         if (!par->gpio.wr) {
1123                 dev_err(par->info->device, "Missing 'wr' gpio. Aborting.\n");
1124                 return -EINVAL;
1125         }
1126         for (i = 0; i < pdata->display.buswidth; i++) {
1127                 if (!par->gpio.db[i]) {
1128                         dev_err(par->info->device,
1129                                 "Missing 'db%02d' gpio. Aborting.\n", i);
1130                         return -EINVAL;
1131                 }
1132         }
1133
1134         return 0;
1135 }
1136
1137 #ifdef CONFIG_OF
1138 /* returns 0 if the property is not present */
1139 static u32 fbtft_of_value(struct device_node *node, const char *propname)
1140 {
1141         int ret;
1142         u32 val = 0;
1143
1144         ret = of_property_read_u32(node, propname, &val);
1145         if (ret == 0)
1146                 pr_info("%s: %s = %u\n", __func__, propname, val);
1147
1148         return val;
1149 }
1150
1151 static struct fbtft_platform_data *fbtft_probe_dt(struct device *dev)
1152 {
1153         struct device_node *node = dev->of_node;
1154         struct fbtft_platform_data *pdata;
1155
1156         if (!node) {
1157                 dev_err(dev, "Missing platform data or DT\n");
1158                 return ERR_PTR(-EINVAL);
1159         }
1160
1161         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
1162         if (!pdata)
1163                 return ERR_PTR(-ENOMEM);
1164
1165         pdata->display.width = fbtft_of_value(node, "width");
1166         pdata->display.height = fbtft_of_value(node, "height");
1167         pdata->display.regwidth = fbtft_of_value(node, "regwidth");
1168         pdata->display.buswidth = fbtft_of_value(node, "buswidth");
1169         pdata->display.backlight = fbtft_of_value(node, "backlight");
1170         pdata->display.bpp = fbtft_of_value(node, "bpp");
1171         pdata->display.debug = fbtft_of_value(node, "debug");
1172         pdata->rotate = fbtft_of_value(node, "rotate");
1173         pdata->bgr = of_property_read_bool(node, "bgr");
1174         pdata->fps = fbtft_of_value(node, "fps");
1175         pdata->txbuflen = fbtft_of_value(node, "txbuflen");
1176         pdata->startbyte = fbtft_of_value(node, "startbyte");
1177         of_property_read_string(node, "gamma", (const char **)&pdata->gamma);
1178
1179         if (of_find_property(node, "led-gpios", NULL))
1180                 pdata->display.backlight = 1;
1181         if (of_find_property(node, "init", NULL))
1182                 pdata->display.fbtftops.init_display = fbtft_init_display_dt;
1183         pdata->display.fbtftops.request_gpios = fbtft_request_gpios_dt;
1184
1185         return pdata;
1186 }
1187 #else
1188 static struct fbtft_platform_data *fbtft_probe_dt(struct device *dev)
1189 {
1190         dev_err(dev, "Missing platform data\n");
1191         return ERR_PTR(-EINVAL);
1192 }
1193 #endif
1194
1195 /**
1196  * fbtft_probe_common() - Generic device probe() helper function
1197  * @display: Display properties
1198  * @sdev: SPI device
1199  * @pdev: Platform device
1200  *
1201  * Allocates, initializes and registers a framebuffer
1202  *
1203  * Either @sdev or @pdev should be NULL
1204  *
1205  * Return: 0 if successful, negative if error
1206  */
1207 int fbtft_probe_common(struct fbtft_display *display,
1208                        struct spi_device *sdev,
1209                        struct platform_device *pdev)
1210 {
1211         struct device *dev;
1212         struct fb_info *info;
1213         struct fbtft_par *par;
1214         struct fbtft_platform_data *pdata;
1215         int ret;
1216
1217         if (sdev)
1218                 dev = &sdev->dev;
1219         else
1220                 dev = &pdev->dev;
1221
1222         if (unlikely(display->debug & DEBUG_DRIVER_INIT_FUNCTIONS))
1223                 dev_info(dev, "%s()\n", __func__);
1224
1225         pdata = dev->platform_data;
1226         if (!pdata) {
1227                 pdata = fbtft_probe_dt(dev);
1228                 if (IS_ERR(pdata))
1229                         return PTR_ERR(pdata);
1230         }
1231
1232         info = fbtft_framebuffer_alloc(display, dev, pdata);
1233         if (!info)
1234                 return -ENOMEM;
1235
1236         par = info->par;
1237         par->spi = sdev;
1238         par->pdev = pdev;
1239
1240         if (display->buswidth == 0) {
1241                 dev_err(dev, "buswidth is not set\n");
1242                 return -EINVAL;
1243         }
1244
1245         /* write register functions */
1246         if (display->regwidth == 8 && display->buswidth == 8)
1247                 par->fbtftops.write_register = fbtft_write_reg8_bus8;
1248         else if (display->regwidth == 8 && display->buswidth == 9 && par->spi)
1249                 par->fbtftops.write_register = fbtft_write_reg8_bus9;
1250         else if (display->regwidth == 16 && display->buswidth == 8)
1251                 par->fbtftops.write_register = fbtft_write_reg16_bus8;
1252         else if (display->regwidth == 16 && display->buswidth == 16)
1253                 par->fbtftops.write_register = fbtft_write_reg16_bus16;
1254         else
1255                 dev_warn(dev,
1256                          "no default functions for regwidth=%d and buswidth=%d\n",
1257                          display->regwidth, display->buswidth);
1258
1259         /* write_vmem() functions */
1260         if (display->buswidth == 8)
1261                 par->fbtftops.write_vmem = fbtft_write_vmem16_bus8;
1262         else if (display->buswidth == 9)
1263                 par->fbtftops.write_vmem = fbtft_write_vmem16_bus9;
1264         else if (display->buswidth == 16)
1265                 par->fbtftops.write_vmem = fbtft_write_vmem16_bus16;
1266
1267         /* GPIO write() functions */
1268         if (par->pdev) {
1269                 if (display->buswidth == 8)
1270                         par->fbtftops.write = fbtft_write_gpio8_wr;
1271                 else if (display->buswidth == 16)
1272                         par->fbtftops.write = fbtft_write_gpio16_wr;
1273         }
1274
1275         /* 9-bit SPI setup */
1276         if (par->spi && display->buswidth == 9) {
1277                 if (par->spi->master->bits_per_word_mask & SPI_BPW_MASK(9)) {
1278                         par->spi->bits_per_word = 9;
1279                 } else {
1280                         dev_warn(&par->spi->dev,
1281                                  "9-bit SPI not available, emulating using 8-bit.\n");
1282                         /* allocate buffer with room for dc bits */
1283                         par->extra = devm_kzalloc(par->info->device,
1284                                                   par->txbuf.len +
1285                                                   (par->txbuf.len / 8) + 8,
1286                                                   GFP_KERNEL);
1287                         if (!par->extra) {
1288                                 ret = -ENOMEM;
1289                                 goto out_release;
1290                         }
1291                         par->fbtftops.write = fbtft_write_spi_emulate_9;
1292                 }
1293         }
1294
1295         if (!par->fbtftops.verify_gpios)
1296                 par->fbtftops.verify_gpios = fbtft_verify_gpios;
1297
1298         /* make sure we still use the driver provided functions */
1299         fbtft_merge_fbtftops(&par->fbtftops, &display->fbtftops);
1300
1301         /* use init_sequence if provided */
1302         if (par->init_sequence)
1303                 par->fbtftops.init_display = fbtft_init_display;
1304
1305         /* use platform_data provided functions above all */
1306         fbtft_merge_fbtftops(&par->fbtftops, &pdata->display.fbtftops);
1307
1308         ret = fbtft_register_framebuffer(info);
1309         if (ret < 0)
1310                 goto out_release;
1311
1312         return 0;
1313
1314 out_release:
1315         fbtft_framebuffer_release(info);
1316
1317         return ret;
1318 }
1319 EXPORT_SYMBOL(fbtft_probe_common);
1320
1321 /**
1322  * fbtft_remove_common() - Generic device remove() helper function
1323  * @dev: Device
1324  * @info: Framebuffer
1325  *
1326  * Unregisters and releases the framebuffer
1327  *
1328  * Return: 0 if successful, negative if error
1329  */
1330 int fbtft_remove_common(struct device *dev, struct fb_info *info)
1331 {
1332         struct fbtft_par *par;
1333
1334         if (!info)
1335                 return -EINVAL;
1336         par = info->par;
1337         if (par)
1338                 fbtft_par_dbg(DEBUG_DRIVER_INIT_FUNCTIONS, par,
1339                               "%s()\n", __func__);
1340         fbtft_unregister_framebuffer(info);
1341         fbtft_framebuffer_release(info);
1342
1343         return 0;
1344 }
1345 EXPORT_SYMBOL(fbtft_remove_common);
1346
1347 MODULE_LICENSE("GPL");