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.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 <linux/of_gpio.h>
  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         if (gpio_is_valid(par->gpio.dc))
  42                 gpio_set_value(par->gpio.dc, dc);
  43
  44         ret = par->fbtftops.write(par, buf, len);
  45         if (ret < 0)
  46                 dev_err(par->info->device,
  47                         "write() failed and returned %d\n", ret);
  48         return ret;
  49 }
  50 EXPORT_SYMBOL(fbtft_write_buf_dc);
  51
  52 void fbtft_dbg_hex(const struct device *dev, int groupsize,
  53                    void *buf, size_t len, const char *fmt, ...)
  54 {
  55         va_list args;
  56         static char textbuf[512];
  57         char *text = textbuf;
  58         size_t text_len;
  59
  60         va_start(args, fmt);
  61         text_len = vscnprintf(text, sizeof(textbuf), fmt, args);
  62         va_end(args);
  63
  64         hex_dump_to_buffer(buf, len, 32, groupsize, text + text_len,
  65                            512 - text_len, false);
  66
  67         if (len > 32)
  68                 dev_info(dev, "%s ...\n", text);
  69         else
  70                 dev_info(dev, "%s\n", text);
  71 }
  72 EXPORT_SYMBOL(fbtft_dbg_hex);
  73
  74 static unsigned long fbtft_request_gpios_match(struct fbtft_par *par,
  75                                                const struct fbtft_gpio *gpio)
  76 {
  77         int ret;
  78         unsigned int val;
  79
  80         fbtft_par_dbg(DEBUG_REQUEST_GPIOS_MATCH, par, "%s('%s')\n",
  81                       __func__, gpio->name);
  82
  83         if (strcasecmp(gpio->name, "reset") == 0) {
  84                 par->gpio.reset = gpio->gpio;
  85                 return GPIOF_OUT_INIT_HIGH;
  86         } else if (strcasecmp(gpio->name, "dc") == 0) {
  87                 par->gpio.dc = gpio->gpio;
  88                 return GPIOF_OUT_INIT_LOW;
  89         } else if (strcasecmp(gpio->name, "cs") == 0) {
  90                 par->gpio.cs = gpio->gpio;
  91                 return GPIOF_OUT_INIT_HIGH;
  92         } else if (strcasecmp(gpio->name, "wr") == 0) {
  93                 par->gpio.wr = gpio->gpio;
  94                 return GPIOF_OUT_INIT_HIGH;
  95         } else if (strcasecmp(gpio->name, "rd") == 0) {
  96                 par->gpio.rd = gpio->gpio;
  97                 return GPIOF_OUT_INIT_HIGH;
  98         } else if (strcasecmp(gpio->name, "latch") == 0) {
  99                 par->gpio.latch = gpio->gpio;
 100                 return GPIOF_OUT_INIT_LOW;
 101         } else if (gpio->name[0] == 'd' && gpio->name[1] == 'b') {
 102                 ret = kstrtouint(&gpio->name[2], 10, &val);
 103                 if (ret == 0 && val < 16) {
 104                         par->gpio.db[val] = gpio->gpio;
 105                         return GPIOF_OUT_INIT_LOW;
 106                 }
 107         } else if (strcasecmp(gpio->name, "led") == 0) {
 108                 par->gpio.led[0] = gpio->gpio;
 109                 return GPIOF_OUT_INIT_LOW;
 110         } else if (strcasecmp(gpio->name, "led_") == 0) {
 111                 par->gpio.led[0] = gpio->gpio;
 112                 return GPIOF_OUT_INIT_HIGH;
 113         }
 114
 115         return FBTFT_GPIO_NO_MATCH;
 116 }
 117
 118 static int fbtft_request_gpios(struct fbtft_par *par)
 119 {
 120         struct fbtft_platform_data *pdata = par->pdata;
 121         const struct fbtft_gpio *gpio;
 122         unsigned long flags;
 123         int ret;
 124
 125         if (!(pdata && pdata->gpios))
 126                 return 0;
 127
 128         gpio = pdata->gpios;
 129         while (gpio->name[0]) {
 130                 flags = FBTFT_GPIO_NO_MATCH;
 131                 /* if driver provides match function, try it first,
 132                  * if no match use our own
 133                  */
 134                 if (par->fbtftops.request_gpios_match)
 135                         flags = par->fbtftops.request_gpios_match(par, gpio);
 136                 if (flags == FBTFT_GPIO_NO_MATCH)
 137                         flags = fbtft_request_gpios_match(par, gpio);
 138                 if (flags != FBTFT_GPIO_NO_MATCH) {
 139                         ret = devm_gpio_request_one(par->info->device,
 140                                               gpio->gpio, flags,
 141                                               par->info->device->driver->name);
 142                         if (ret < 0) {
 143                                 dev_err(par->info->device,
 144                                         "%s: gpio_request_one('%s'=%d) failed with %d\n",
 145                                         __func__, gpio->name,
 146                                         gpio->gpio, ret);
 147                                 return ret;
 148                         }
 149                         fbtft_par_dbg(DEBUG_REQUEST_GPIOS, par,
 150                                       "%s: '%s' = GPIO%d\n",
 151                                       __func__, gpio->name, gpio->gpio);
 152                 }
 153                 gpio++;
 154         }
 155
 156         return 0;
 157 }
 158
 159 #ifdef CONFIG_OF
 160 static int fbtft_request_one_gpio(struct fbtft_par *par,
 161                                   const char *name, int index, int *gpiop)
 162 {
 163         struct device *dev = par->info->device;
 164         struct device_node *node = dev->of_node;
 165         int gpio, flags, ret = 0;
 166         enum of_gpio_flags of_flags;
 167
 168         if (of_find_property(node, name, NULL)) {
 169                 gpio = of_get_named_gpio_flags(node, name, index, &of_flags);
 170                 if (gpio == -ENOENT)
 171                         return 0;
 172                 if (gpio == -EPROBE_DEFER)
 173                         return gpio;
 174                 if (gpio < 0) {
 175                         dev_err(dev,
 176                                 "failed to get '%s' from DT\n", name);
 177                         return gpio;
 178                 }
 179
 180                 /* active low translates to initially low */
 181                 flags = (of_flags & OF_GPIO_ACTIVE_LOW) ? GPIOF_OUT_INIT_LOW :
 182                                                         GPIOF_OUT_INIT_HIGH;
 183                 ret = devm_gpio_request_one(dev, gpio, flags,
 184                                             dev->driver->name);
 185                 if (ret) {
 186                         dev_err(dev,
 187                                 "gpio_request_one('%s'=%d) failed with %d\n",
 188                                 name, gpio, ret);
 189                         return ret;
 190                 }
 191                 if (gpiop)
 192                         *gpiop = gpio;
 193                 fbtft_par_dbg(DEBUG_REQUEST_GPIOS, par, "%s: '%s' = GPIO%d\n",
 194                               __func__, name, gpio);
 195         }
 196
 197         return ret;
 198 }
 199
 200 static int fbtft_request_gpios_dt(struct fbtft_par *par)
 201 {
 202         int i;
 203         int ret;
 204
 205         if (!par->info->device->of_node)
 206                 return -EINVAL;
 207
 208         ret = fbtft_request_one_gpio(par, "reset-gpios", 0, &par->gpio.reset);
 209         if (ret)
 210                 return ret;
 211         ret = fbtft_request_one_gpio(par, "dc-gpios", 0, &par->gpio.dc);
 212         if (ret)
 213                 return ret;
 214         ret = fbtft_request_one_gpio(par, "rd-gpios", 0, &par->gpio.rd);
 215         if (ret)
 216                 return ret;
 217         ret = fbtft_request_one_gpio(par, "wr-gpios", 0, &par->gpio.wr);
 218         if (ret)
 219                 return ret;
 220         ret = fbtft_request_one_gpio(par, "cs-gpios", 0, &par->gpio.cs);
 221         if (ret)
 222                 return ret;
 223         ret = fbtft_request_one_gpio(par, "latch-gpios", 0, &par->gpio.latch);
 224         if (ret)
 225                 return ret;
 226         for (i = 0; i < 16; i++) {
 227                 ret = fbtft_request_one_gpio(par, "db-gpios", i,
 228                                              &par->gpio.db[i]);
 229                 if (ret)
 230                         return ret;
 231                 ret = fbtft_request_one_gpio(par, "led-gpios", i,
 232                                              &par->gpio.led[i]);
 233                 if (ret)
 234                         return ret;
 235                 ret = fbtft_request_one_gpio(par, "aux-gpios", i,
 236                                              &par->gpio.aux[i]);
 237                 if (ret)
 238                         return ret;
 239         }
 240
 241         return 0;
 242 }
 243 #endif
 244
 245 #ifdef CONFIG_FB_BACKLIGHT
 246 static int fbtft_backlight_update_status(struct backlight_device *bd)
 247 {
 248         struct fbtft_par *par = bl_get_data(bd);
 249         bool polarity = par->polarity;
 250
 251         fbtft_par_dbg(DEBUG_BACKLIGHT, par,
 252                       "%s: polarity=%d, power=%d, fb_blank=%d\n",
 253                       __func__, polarity, bd->props.power, bd->props.fb_blank);
 254
 255         if ((bd->props.power == FB_BLANK_UNBLANK) &&
 256             (bd->props.fb_blank == FB_BLANK_UNBLANK))
 257                 gpio_set_value(par->gpio.led[0], polarity);
 258         else
 259                 gpio_set_value(par->gpio.led[0], !polarity);
 260
 261         return 0;
 262 }
 263
 264 static int fbtft_backlight_get_brightness(struct backlight_device *bd)
 265 {
 266         return bd->props.brightness;
 267 }
 268
 269 void fbtft_unregister_backlight(struct fbtft_par *par)
 270 {
 271         if (par->info->bl_dev) {
 272                 par->info->bl_dev->props.power = FB_BLANK_POWERDOWN;
 273                 backlight_update_status(par->info->bl_dev);
 274                 backlight_device_unregister(par->info->bl_dev);
 275                 par->info->bl_dev = NULL;
 276         }
 277 }
 278
 279 static const struct backlight_ops fbtft_bl_ops = {
 280         .get_brightness = fbtft_backlight_get_brightness,
 281         .update_status  = fbtft_backlight_update_status,
 282 };
 283
 284 void fbtft_register_backlight(struct fbtft_par *par)
 285 {
 286         struct backlight_device *bd;
 287         struct backlight_properties bl_props = { 0, };
 288
 289         if (par->gpio.led[0] == -1) {
 290                 fbtft_par_dbg(DEBUG_BACKLIGHT, par,
 291                               "%s(): led pin not set, exiting.\n", __func__);
 292                 return;
 293         }
 294
 295         bl_props.type = BACKLIGHT_RAW;
 296         /* Assume backlight is off, get polarity from current state of pin */
 297         bl_props.power = FB_BLANK_POWERDOWN;
 298         if (!gpio_get_value(par->gpio.led[0]))
 299                 par->polarity = true;
 300
 301         bd = backlight_device_register(dev_driver_string(par->info->device),
 302                                        par->info->device, par,
 303                                        &fbtft_bl_ops, &bl_props);
 304         if (IS_ERR(bd)) {
 305                 dev_err(par->info->device,
 306                         "cannot register backlight device (%ld)\n",
 307                         PTR_ERR(bd));
 308                 return;
 309         }
 310         par->info->bl_dev = bd;
 311
 312         if (!par->fbtftops.unregister_backlight)
 313                 par->fbtftops.unregister_backlight = fbtft_unregister_backlight;
 314 }
 315 #else
 316 void fbtft_register_backlight(struct fbtft_par *par) { };
 317 void fbtft_unregister_backlight(struct fbtft_par *par) { };
 318 #endif
 319 EXPORT_SYMBOL(fbtft_register_backlight);
 320 EXPORT_SYMBOL(fbtft_unregister_backlight);
 321
 322 static void fbtft_set_addr_win(struct fbtft_par *par, int xs, int ys, int xe,
 323                                int ye)
 324 {
 325         write_reg(par, MIPI_DCS_SET_COLUMN_ADDRESS,
 326                   (xs >> 8) & 0xFF, xs & 0xFF, (xe >> 8) & 0xFF, xe & 0xFF);
 327
 328         write_reg(par, MIPI_DCS_SET_PAGE_ADDRESS,
 329                   (ys >> 8) & 0xFF, ys & 0xFF, (ye >> 8) & 0xFF, ye & 0xFF);
 330
 331         write_reg(par, MIPI_DCS_WRITE_MEMORY_START);
 332 }
 333
 334 static void fbtft_reset(struct fbtft_par *par)
 335 {
 336         if (par->gpio.reset == -1)
 337                 return;
 338         fbtft_par_dbg(DEBUG_RESET, par, "%s()\n", __func__);
 339         gpio_set_value_cansleep(par->gpio.reset, 0);
 340         usleep_range(20, 40);
 341         gpio_set_value_cansleep(par->gpio.reset, 1);
 342         msleep(120);
 343 }
 344
 345 static void fbtft_update_display(struct fbtft_par *par, unsigned int start_line,
 346                                  unsigned int end_line)
 347 {
 348         size_t offset, len;
 349         ktime_t ts_start, ts_end;
 350         long fps, throughput;
 351         bool timeit = false;
 352         int ret = 0;
 353
 354         if (unlikely(par->debug & (DEBUG_TIME_FIRST_UPDATE |
 355                         DEBUG_TIME_EACH_UPDATE))) {
 356                 if ((par->debug & DEBUG_TIME_EACH_UPDATE) ||
 357                     ((par->debug & DEBUG_TIME_FIRST_UPDATE) &&
 358                     !par->first_update_done)) {
 359                         ts_start = ktime_get();
 360                         timeit = true;
 361                 }
 362         }
 363
 364         /* Sanity checks */
 365         if (start_line > end_line) {
 366                 dev_warn(par->info->device,
 367                          "%s: start_line=%u is larger than end_line=%u. Shouldn't happen, will do full display update\n",
 368                          __func__, start_line, end_line);
 369                 start_line = 0;
 370                 end_line = par->info->var.yres - 1;
 371         }
 372         if (start_line > par->info->var.yres - 1 ||
 373             end_line > par->info->var.yres - 1) {
 374                 dev_warn(par->info->device,
 375                          "%s: start_line=%u or end_line=%u is larger than max=%d. Shouldn't happen, will do full display update\n",
 376                          __func__, start_line,
 377                          end_line, par->info->var.yres - 1);
 378                 start_line = 0;
 379                 end_line = par->info->var.yres - 1;
 380         }
 381
 382         fbtft_par_dbg(DEBUG_UPDATE_DISPLAY, par, "%s(start_line=%u, end_line=%u)\n",
 383                       __func__, start_line, end_line);
 384
 385         if (par->fbtftops.set_addr_win)
 386                 par->fbtftops.set_addr_win(par, 0, start_line,
 387                                 par->info->var.xres - 1, end_line);
 388
 389         offset = start_line * par->info->fix.line_length;
 390         len = (end_line - start_line + 1) * par->info->fix.line_length;
 391         ret = par->fbtftops.write_vmem(par, offset, len);
 392         if (ret < 0)
 393                 dev_err(par->info->device,
 394                         "%s: write_vmem failed to update display buffer\n",
 395                         __func__);
 396
 397         if (unlikely(timeit)) {
 398                 ts_end = ktime_get();
 399                 if (!ktime_to_ns(par->update_time))
 400                         par->update_time = ts_start;
 401
 402                 fps = ktime_us_delta(ts_start, par->update_time);
 403                 par->update_time = ts_start;
 404                 fps = fps ? 1000000 / fps : 0;
 405
 406                 throughput = ktime_us_delta(ts_end, ts_start);
 407                 throughput = throughput ? (len * 1000) / throughput : 0;
 408                 throughput = throughput * 1000 / 1024;
 409
 410                 dev_info(par->info->device,
 411                          "Display update: %ld kB/s, fps=%ld\n",
 412                          throughput, fps);
 413                 par->first_update_done = true;
 414         }
 415 }
 416
 417 static void fbtft_mkdirty(struct fb_info *info, int y, int height)
 418 {
 419         struct fbtft_par *par = info->par;
 420         struct fb_deferred_io *fbdefio = info->fbdefio;
 421
 422         /* special case, needed ? */
 423         if (y == -1) {
 424                 y = 0;
 425                 height = info->var.yres - 1;
 426         }
 427
 428         /* Mark display lines/area as dirty */
 429         spin_lock(&par->dirty_lock);
 430         if (y < par->dirty_lines_start)
 431                 par->dirty_lines_start = y;
 432         if (y + height - 1 > par->dirty_lines_end)
 433                 par->dirty_lines_end = y + height - 1;
 434         spin_unlock(&par->dirty_lock);
 435
 436         /* Schedule deferred_io to update display (no-op if already on queue)*/
 437         schedule_delayed_work(&info->deferred_work, fbdefio->delay);
 438 }
 439
 440 static void fbtft_deferred_io(struct fb_info *info, struct list_head *pagelist)
 441 {
 442         struct fbtft_par *par = info->par;
 443         unsigned int dirty_lines_start, dirty_lines_end;
 444         struct page *page;
 445         unsigned long index;
 446         unsigned int y_low = 0, y_high = 0;
 447         int count = 0;
 448
 449         spin_lock(&par->dirty_lock);
 450         dirty_lines_start = par->dirty_lines_start;
 451         dirty_lines_end = par->dirty_lines_end;
 452         /* set display line markers as clean */
 453         par->dirty_lines_start = par->info->var.yres - 1;
 454         par->dirty_lines_end = 0;
 455         spin_unlock(&par->dirty_lock);
 456
 457         /* Mark display lines as dirty */
 458         list_for_each_entry(page, pagelist, lru) {
 459                 count++;
 460                 index = page->index << PAGE_SHIFT;
 461                 y_low = index / info->fix.line_length;
 462                 y_high = (index + PAGE_SIZE - 1) / info->fix.line_length;
 463                 dev_dbg(info->device,
 464                         "page->index=%lu y_low=%d y_high=%d\n",
 465                         page->index, y_low, y_high);
 466                 if (y_high > info->var.yres - 1)
 467                         y_high = info->var.yres - 1;
 468                 if (y_low < dirty_lines_start)
 469                         dirty_lines_start = y_low;
 470                 if (y_high > dirty_lines_end)
 471                         dirty_lines_end = y_high;
 472         }
 473
 474         par->fbtftops.update_display(info->par,
 475                                         dirty_lines_start, dirty_lines_end);
 476 }
 477
 478 static void fbtft_fb_fillrect(struct fb_info *info,
 479                               const struct fb_fillrect *rect)
 480 {
 481         struct fbtft_par *par = info->par;
 482
 483         dev_dbg(info->dev,
 484                 "%s: dx=%d, dy=%d, width=%d, height=%d\n",
 485                 __func__, rect->dx, rect->dy, rect->width, rect->height);
 486         sys_fillrect(info, rect);
 487
 488         par->fbtftops.mkdirty(info, rect->dy, rect->height);
 489 }
 490
 491 static void fbtft_fb_copyarea(struct fb_info *info,
 492                               const struct fb_copyarea *area)
 493 {
 494         struct fbtft_par *par = info->par;
 495
 496         dev_dbg(info->dev,
 497                 "%s: dx=%d, dy=%d, width=%d, height=%d\n",
 498                 __func__,  area->dx, area->dy, area->width, area->height);
 499         sys_copyarea(info, area);
 500
 501         par->fbtftops.mkdirty(info, area->dy, area->height);
 502 }
 503
 504 static void fbtft_fb_imageblit(struct fb_info *info,
 505                                const struct fb_image *image)
 506 {
 507         struct fbtft_par *par = info->par;
 508
 509         dev_dbg(info->dev,
 510                 "%s: dx=%d, dy=%d, width=%d, height=%d\n",
 511                 __func__,  image->dx, image->dy, image->width, image->height);
 512         sys_imageblit(info, image);
 513
 514         par->fbtftops.mkdirty(info, image->dy, image->height);
 515 }
 516
 517 static ssize_t fbtft_fb_write(struct fb_info *info, const char __user *buf,
 518                               size_t count, loff_t *ppos)
 519 {
 520         struct fbtft_par *par = info->par;
 521         ssize_t res;
 522
 523         dev_dbg(info->dev,
 524                 "%s: count=%zd, ppos=%llu\n", __func__,  count, *ppos);
 525         res = fb_sys_write(info, buf, count, ppos);
 526
 527         /* TODO: only mark changed area update all for now */
 528         par->fbtftops.mkdirty(info, -1, 0);
 529
 530         return res;
 531 }
 532
 533 /* from pxafb.c */
 534 static unsigned int chan_to_field(unsigned int chan, struct fb_bitfield *bf)
 535 {
 536         chan &= 0xffff;
 537         chan >>= 16 - bf->length;
 538         return chan << bf->offset;
 539 }
 540
 541 static int fbtft_fb_setcolreg(unsigned int regno, unsigned int red, unsigned int green,
 542                               unsigned int blue, unsigned int transp,
 543                               struct fb_info *info)
 544 {
 545         unsigned int val;
 546         int ret = 1;
 547
 548         dev_dbg(info->dev,
 549                 "%s(regno=%u, red=0x%X, green=0x%X, blue=0x%X, trans=0x%X)\n",
 550                 __func__, regno, red, green, blue, transp);
 551
 552         switch (info->fix.visual) {
 553         case FB_VISUAL_TRUECOLOR:
 554                 if (regno < 16) {
 555                         u32 *pal = info->pseudo_palette;
 556
 557                         val  = chan_to_field(red,   &info->var.red);
 558                         val |= chan_to_field(green, &info->var.green);
 559                         val |= chan_to_field(blue,  &info->var.blue);
 560
 561                         pal[regno] = val;
 562                         ret = 0;
 563                 }
 564                 break;
 565         }
 566         return ret;
 567 }
 568
 569 static int fbtft_fb_blank(int blank, struct fb_info *info)
 570 {
 571         struct fbtft_par *par = info->par;
 572         int ret = -EINVAL;
 573
 574         dev_dbg(info->dev, "%s(blank=%d)\n",
 575                 __func__, blank);
 576
 577         if (!par->fbtftops.blank)
 578                 return ret;
 579
 580         switch (blank) {
 581         case FB_BLANK_POWERDOWN:
 582         case FB_BLANK_VSYNC_SUSPEND:
 583         case FB_BLANK_HSYNC_SUSPEND:
 584         case FB_BLANK_NORMAL:
 585                 ret = par->fbtftops.blank(par, true);
 586                 break;
 587         case FB_BLANK_UNBLANK:
 588                 ret = par->fbtftops.blank(par, false);
 589                 break;
 590         }
 591         return ret;
 592 }
 593
 594 static void fbtft_merge_fbtftops(struct fbtft_ops *dst, struct fbtft_ops *src)
 595 {
 596         if (src->write)
 597                 dst->write = src->write;
 598         if (src->read)
 599                 dst->read = src->read;
 600         if (src->write_vmem)
 601                 dst->write_vmem = src->write_vmem;
 602         if (src->write_register)
 603                 dst->write_register = src->write_register;
 604         if (src->set_addr_win)
 605                 dst->set_addr_win = src->set_addr_win;
 606         if (src->reset)
 607                 dst->reset = src->reset;
 608         if (src->mkdirty)
 609                 dst->mkdirty = src->mkdirty;
 610         if (src->update_display)
 611                 dst->update_display = src->update_display;
 612         if (src->init_display)
 613                 dst->init_display = src->init_display;
 614         if (src->blank)
 615                 dst->blank = src->blank;
 616         if (src->request_gpios_match)
 617                 dst->request_gpios_match = src->request_gpios_match;
 618         if (src->request_gpios)
 619                 dst->request_gpios = src->request_gpios;
 620         if (src->verify_gpios)
 621                 dst->verify_gpios = src->verify_gpios;
 622         if (src->register_backlight)
 623                 dst->register_backlight = src->register_backlight;
 624         if (src->unregister_backlight)
 625                 dst->unregister_backlight = src->unregister_backlight;
 626         if (src->set_var)
 627                 dst->set_var = src->set_var;
 628         if (src->set_gamma)
 629                 dst->set_gamma = src->set_gamma;
 630 }
 631
 632 /**
 633  * fbtft_framebuffer_alloc - creates a new frame buffer info structure
 634  *
 635  * @display: pointer to structure describing the display
 636  * @dev: pointer to the device for this fb, this can be NULL
 637  *
 638  * Creates a new frame buffer info structure.
 639  *
 640  * Also creates and populates the following structures:
 641  *   info->fbops
 642  *   info->fbdefio
 643  *   info->pseudo_palette
 644  *   par->fbtftops
 645  *   par->txbuf
 646  *
 647  * Returns the new structure, or NULL if an error occurred.
 648  *
 649  */
 650 struct fb_info *fbtft_framebuffer_alloc(struct fbtft_display *display,
 651                                         struct device *dev,
 652                                         struct fbtft_platform_data *pdata)
 653 {
 654         struct fb_info *info;
 655         struct fbtft_par *par;
 656         struct fb_ops *fbops = NULL;
 657         struct fb_deferred_io *fbdefio = NULL;
 658         u8 *vmem = NULL;
 659         void *txbuf = NULL;
 660         void *buf = NULL;
 661         unsigned int width;
 662         unsigned int height;
 663         int txbuflen = display->txbuflen;
 664         unsigned int bpp = display->bpp;
 665         unsigned int fps = display->fps;
 666         int vmem_size, i;
 667         const s16 *init_sequence = display->init_sequence;
 668         char *gamma = display->gamma;
 669         u32 *gamma_curves = NULL;
 670
 671         /* sanity check */
 672         if (display->gamma_num * display->gamma_len >
 673                         FBTFT_GAMMA_MAX_VALUES_TOTAL) {
 674                 dev_err(dev, "FBTFT_GAMMA_MAX_VALUES_TOTAL=%d is exceeded\n",
 675                         FBTFT_GAMMA_MAX_VALUES_TOTAL);
 676                 return NULL;
 677         }
 678
 679         /* defaults */
 680         if (!fps)
 681                 fps = 20;
 682         if (!bpp)
 683                 bpp = 16;
 684
 685         if (!pdata) {
 686                 dev_err(dev, "platform data is missing\n");
 687                 return NULL;
 688         }
 689
 690         /* override driver values? */
 691         if (pdata->fps)
 692                 fps = pdata->fps;
 693         if (pdata->txbuflen)
 694                 txbuflen = pdata->txbuflen;
 695         if (pdata->display.init_sequence)
 696                 init_sequence = pdata->display.init_sequence;
 697         if (pdata->gamma)
 698                 gamma = pdata->gamma;
 699         if (pdata->display.debug)
 700                 display->debug = pdata->display.debug;
 701         if (pdata->display.backlight)
 702                 display->backlight = pdata->display.backlight;
 703         if (pdata->display.width)
 704                 display->width = pdata->display.width;
 705         if (pdata->display.height)
 706                 display->height = pdata->display.height;
 707         if (pdata->display.buswidth)
 708                 display->buswidth = pdata->display.buswidth;
 709         if (pdata->display.regwidth)
 710                 display->regwidth = pdata->display.regwidth;
 711
 712         display->debug |= debug;
 713         fbtft_expand_debug_value(&display->debug);
 714
 715         switch (pdata->rotate) {
 716         case 90:
 717         case 270:
 718                 width =  display->height;
 719                 height = display->width;
 720                 break;
 721         default:
 722                 width =  display->width;
 723                 height = display->height;
 724         }
 725
 726         vmem_size = display->width * display->height * bpp / 8;
 727         vmem = vzalloc(vmem_size);
 728         if (!vmem)
 729                 goto alloc_fail;
 730
 731         fbops = devm_kzalloc(dev, sizeof(struct fb_ops), GFP_KERNEL);
 732         if (!fbops)
 733                 goto alloc_fail;
 734
 735         fbdefio = devm_kzalloc(dev, sizeof(struct fb_deferred_io), GFP_KERNEL);
 736         if (!fbdefio)
 737                 goto alloc_fail;
 738
 739         buf = devm_kzalloc(dev, 128, GFP_KERNEL);
 740         if (!buf)
 741                 goto alloc_fail;
 742
 743         if (display->gamma_num && display->gamma_len) {
 744                 gamma_curves = devm_kcalloc(dev,
 745                                             display->gamma_num *
 746                                             display->gamma_len,
 747                                             sizeof(gamma_curves[0]),
 748                                             GFP_KERNEL);
 749                 if (!gamma_curves)
 750                         goto alloc_fail;
 751         }
 752
 753         info = framebuffer_alloc(sizeof(struct fbtft_par), dev);
 754         if (!info)
 755                 goto alloc_fail;
 756
 757         info->screen_buffer = vmem;
 758         info->fbops = fbops;
 759         info->fbdefio = fbdefio;
 760
 761         fbops->owner        =      dev->driver->owner;
 762         fbops->fb_read      =      fb_sys_read;
 763         fbops->fb_write     =      fbtft_fb_write;
 764         fbops->fb_fillrect  =      fbtft_fb_fillrect;
 765         fbops->fb_copyarea  =      fbtft_fb_copyarea;
 766         fbops->fb_imageblit =      fbtft_fb_imageblit;
 767         fbops->fb_setcolreg =      fbtft_fb_setcolreg;
 768         fbops->fb_blank     =      fbtft_fb_blank;
 769
 770         fbdefio->delay =           HZ / fps;
 771         fbdefio->deferred_io =     fbtft_deferred_io;
 772         fb_deferred_io_init(info);
 773
 774         snprintf(info->fix.id, sizeof(info->fix.id), "%s", dev->driver->name);
 775         info->fix.type =           FB_TYPE_PACKED_PIXELS;
 776         info->fix.visual =         FB_VISUAL_TRUECOLOR;
 777         info->fix.xpanstep =       0;
 778         info->fix.ypanstep =       0;
 779         info->fix.ywrapstep =      0;
 780         info->fix.line_length =    width * bpp / 8;
 781         info->fix.accel =          FB_ACCEL_NONE;
 782         info->fix.smem_len =       vmem_size;
 783
 784         info->var.rotate =         pdata->rotate;
 785         info->var.xres =           width;
 786         info->var.yres =           height;
 787         info->var.xres_virtual =   info->var.xres;
 788         info->var.yres_virtual =   info->var.yres;
 789         info->var.bits_per_pixel = bpp;
 790         info->var.nonstd =         1;
 791
 792         /* RGB565 */
 793         info->var.red.offset =     11;
 794         info->var.red.length =     5;
 795         info->var.green.offset =   5;
 796         info->var.green.length =   6;
 797         info->var.blue.offset =    0;
 798         info->var.blue.length =    5;
 799         info->var.transp.offset =  0;
 800         info->var.transp.length =  0;
 801
 802         info->flags =              FBINFO_FLAG_DEFAULT | FBINFO_VIRTFB;
 803
 804         par = info->par;
 805         par->info = info;
 806         par->pdata = pdata;
 807         par->debug = display->debug;
 808         par->buf = buf;
 809         spin_lock_init(&par->dirty_lock);
 810         par->bgr = pdata->bgr;
 811         par->startbyte = pdata->startbyte;
 812         par->init_sequence = init_sequence;
 813         par->gamma.curves = gamma_curves;
 814         par->gamma.num_curves = display->gamma_num;
 815         par->gamma.num_values = display->gamma_len;
 816         mutex_init(&par->gamma.lock);
 817         info->pseudo_palette = par->pseudo_palette;
 818
 819         if (par->gamma.curves && gamma) {
 820                 if (fbtft_gamma_parse_str(par, par->gamma.curves, gamma,
 821                                           strlen(gamma)))
 822                         goto release_framebuf;
 823         }
 824
 825         /* Transmit buffer */
 826         if (txbuflen == -1)
 827                 txbuflen = vmem_size + 2; /* add in case startbyte is used */
 828         if (txbuflen >= vmem_size + 2)
 829                 txbuflen = 0;
 830
 831 #ifdef __LITTLE_ENDIAN
 832         if ((!txbuflen) && (bpp > 8))
 833                 txbuflen = PAGE_SIZE; /* need buffer for byteswapping */
 834 #endif
 835
 836         if (txbuflen > 0) {
 837                 txbuf = devm_kzalloc(par->info->device, txbuflen, GFP_KERNEL);
 838                 if (!txbuf)
 839                         goto release_framebuf;
 840                 par->txbuf.buf = txbuf;
 841                 par->txbuf.len = txbuflen;
 842         }
 843
 844         /* Initialize gpios to disabled */
 845         par->gpio.reset = -1;
 846         par->gpio.dc = -1;
 847         par->gpio.rd = -1;
 848         par->gpio.wr = -1;
 849         par->gpio.cs = -1;
 850         par->gpio.latch = -1;
 851         for (i = 0; i < 16; i++) {
 852                 par->gpio.db[i] = -1;
 853                 par->gpio.led[i] = -1;
 854                 par->gpio.aux[i] = -1;
 855         }
 856
 857         /* default fbtft operations */
 858         par->fbtftops.write = fbtft_write_spi;
 859         par->fbtftops.read = fbtft_read_spi;
 860         par->fbtftops.write_vmem = fbtft_write_vmem16_bus8;
 861         par->fbtftops.write_register = fbtft_write_reg8_bus8;
 862         par->fbtftops.set_addr_win = fbtft_set_addr_win;
 863         par->fbtftops.reset = fbtft_reset;
 864         par->fbtftops.mkdirty = fbtft_mkdirty;
 865         par->fbtftops.update_display = fbtft_update_display;
 866         par->fbtftops.request_gpios = fbtft_request_gpios;
 867         if (display->backlight)
 868                 par->fbtftops.register_backlight = fbtft_register_backlight;
 869
 870         /* use driver provided functions */
 871         fbtft_merge_fbtftops(&par->fbtftops, &display->fbtftops);
 872
 873         return info;
 874
 875 release_framebuf:
 876         framebuffer_release(info);
 877
 878 alloc_fail:
 879         vfree(vmem);
 880
 881         return NULL;
 882 }
 883 EXPORT_SYMBOL(fbtft_framebuffer_alloc);
 884
 885 /**
 886  * fbtft_framebuffer_release - frees up all memory used by the framebuffer
 887  *
 888  * @info: frame buffer info structure
 889  *
 890  */
 891 void fbtft_framebuffer_release(struct fb_info *info)
 892 {
 893         fb_deferred_io_cleanup(info);
 894         vfree(info->screen_buffer);
 895         framebuffer_release(info);
 896 }
 897 EXPORT_SYMBOL(fbtft_framebuffer_release);
 898
 899 /**
 900  *      fbtft_register_framebuffer - registers a tft frame buffer device
 901  *      @fb_info: frame buffer info structure
 902  *
 903  *  Sets SPI driverdata if needed
 904  *  Requests needed gpios.
 905  *  Initializes display
 906  *  Updates display.
 907  *      Registers a frame buffer device @fb_info.
 908  *
 909  *      Returns negative errno on error, or zero for success.
 910  *
 911  */
 912 int fbtft_register_framebuffer(struct fb_info *fb_info)
 913 {
 914         int ret;
 915         char text1[50] = "";
 916         char text2[50] = "";
 917         struct fbtft_par *par = fb_info->par;
 918         struct spi_device *spi = par->spi;
 919
 920         /* sanity checks */
 921         if (!par->fbtftops.init_display) {
 922                 dev_err(fb_info->device, "missing fbtftops.init_display()\n");
 923                 return -EINVAL;
 924         }
 925
 926         if (spi)
 927                 spi_set_drvdata(spi, fb_info);
 928         if (par->pdev)
 929                 platform_set_drvdata(par->pdev, fb_info);
 930
 931         ret = par->fbtftops.request_gpios(par);
 932         if (ret < 0)
 933                 goto reg_fail;
 934
 935         if (par->fbtftops.verify_gpios) {
 936                 ret = par->fbtftops.verify_gpios(par);
 937                 if (ret < 0)
 938                         goto reg_fail;
 939         }
 940
 941         ret = par->fbtftops.init_display(par);
 942         if (ret < 0)
 943                 goto reg_fail;
 944         if (par->fbtftops.set_var) {
 945                 ret = par->fbtftops.set_var(par);
 946                 if (ret < 0)
 947                         goto reg_fail;
 948         }
 949
 950         /* update the entire display */
 951         par->fbtftops.update_display(par, 0, par->info->var.yres - 1);
 952
 953         if (par->fbtftops.set_gamma && par->gamma.curves) {
 954                 ret = par->fbtftops.set_gamma(par, par->gamma.curves);
 955                 if (ret)
 956                         goto reg_fail;
 957         }
 958
 959         if (par->fbtftops.register_backlight)
 960                 par->fbtftops.register_backlight(par);
 961
 962         ret = register_framebuffer(fb_info);
 963         if (ret < 0)
 964                 goto reg_fail;
 965
 966         fbtft_sysfs_init(par);
 967
 968         if (par->txbuf.buf && par->txbuf.len >= 1024)
 969                 sprintf(text1, ", %zu KiB buffer memory", par->txbuf.len >> 10);
 970         if (spi)
 971                 sprintf(text2, ", spi%d.%d at %d MHz", spi->master->bus_num,
 972                         spi->chip_select, spi->max_speed_hz / 1000000);
 973         dev_info(fb_info->dev,
 974                  "%s frame buffer, %dx%d, %d KiB video memory%s, fps=%lu%s\n",
 975                  fb_info->fix.id, fb_info->var.xres, fb_info->var.yres,
 976                  fb_info->fix.smem_len >> 10, text1,
 977                  HZ / fb_info->fbdefio->delay, text2);
 978
 979 #ifdef CONFIG_FB_BACKLIGHT
 980         /* Turn on backlight if available */
 981         if (fb_info->bl_dev) {
 982                 fb_info->bl_dev->props.power = FB_BLANK_UNBLANK;
 983                 fb_info->bl_dev->ops->update_status(fb_info->bl_dev);
 984         }
 985 #endif
 986
 987         return 0;
 988
 989 reg_fail:
 990         if (par->fbtftops.unregister_backlight)
 991                 par->fbtftops.unregister_backlight(par);
 992
 993         return ret;
 994 }
 995 EXPORT_SYMBOL(fbtft_register_framebuffer);
 996
 997 /**
 998  *      fbtft_unregister_framebuffer - releases a tft frame buffer device
 999  *      @fb_info: frame buffer info structure
1000  *
1001  *  Frees SPI driverdata if needed
1002  *  Frees gpios.
1003  *      Unregisters frame buffer device.
1004  *
1005  */
1006 int fbtft_unregister_framebuffer(struct fb_info *fb_info)
1007 {
1008         struct fbtft_par *par = fb_info->par;
1009
1010         if (par->fbtftops.unregister_backlight)
1011                 par->fbtftops.unregister_backlight(par);
1012         fbtft_sysfs_exit(par);
1013         return unregister_framebuffer(fb_info);
1014 }
1015 EXPORT_SYMBOL(fbtft_unregister_framebuffer);
1016
1017 #ifdef CONFIG_OF
1018 /**
1019  * fbtft_init_display_dt() - Device Tree init_display() function
1020  * @par: Driver data
1021  *
1022  * Return: 0 if successful, negative if error
1023  */
1024 static int fbtft_init_display_dt(struct fbtft_par *par)
1025 {
1026         struct device_node *node = par->info->device->of_node;
1027         struct property *prop;
1028         const __be32 *p;
1029         u32 val;
1030         int buf[64], i, j;
1031
1032         if (!node)
1033                 return -EINVAL;
1034
1035         prop = of_find_property(node, "init", NULL);
1036         p = of_prop_next_u32(prop, NULL, &val);
1037         if (!p)
1038                 return -EINVAL;
1039
1040         par->fbtftops.reset(par);
1041         if (par->gpio.cs != -1)
1042                 gpio_set_value(par->gpio.cs, 0);  /* Activate chip */
1043
1044         while (p) {
1045                 if (val & FBTFT_OF_INIT_CMD) {
1046                         val &= 0xFFFF;
1047                         i = 0;
1048                         while (p && !(val & 0xFFFF0000)) {
1049                                 if (i > 63) {
1050                                         dev_err(par->info->device,
1051                                                 "%s: Maximum register values exceeded\n",
1052                                                 __func__);
1053                                         return -EINVAL;
1054                                 }
1055                                 buf[i++] = val;
1056                                 p = of_prop_next_u32(prop, p, &val);
1057                         }
1058                         /* make debug message */
1059                         fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
1060                                       "init: write_register:\n");
1061                         for (j = 0; j < i; j++)
1062                                 fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
1063                                               "buf[%d] = %02X\n", j, buf[j]);
1064
1065                         par->fbtftops.write_register(par, i,
1066                                 buf[0], buf[1], buf[2], buf[3],
1067                                 buf[4], buf[5], buf[6], buf[7],
1068                                 buf[8], buf[9], buf[10], buf[11],
1069                                 buf[12], buf[13], buf[14], buf[15],
1070                                 buf[16], buf[17], buf[18], buf[19],
1071                                 buf[20], buf[21], buf[22], buf[23],
1072                                 buf[24], buf[25], buf[26], buf[27],
1073                                 buf[28], buf[29], buf[30], buf[31],
1074                                 buf[32], buf[33], buf[34], buf[35],
1075                                 buf[36], buf[37], buf[38], buf[39],
1076                                 buf[40], buf[41], buf[42], buf[43],
1077                                 buf[44], buf[45], buf[46], buf[47],
1078                                 buf[48], buf[49], buf[50], buf[51],
1079                                 buf[52], buf[53], buf[54], buf[55],
1080                                 buf[56], buf[57], buf[58], buf[59],
1081                                 buf[60], buf[61], buf[62], buf[63]);
1082                 } else if (val & FBTFT_OF_INIT_DELAY) {
1083                         fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
1084                                       "init: msleep(%u)\n", val & 0xFFFF);
1085                         msleep(val & 0xFFFF);
1086                         p = of_prop_next_u32(prop, p, &val);
1087                 } else {
1088                         dev_err(par->info->device, "illegal init value 0x%X\n",
1089                                 val);
1090                         return -EINVAL;
1091                 }
1092         }
1093
1094         return 0;
1095 }
1096 #endif
1097
1098 /**
1099  * fbtft_init_display() - Generic init_display() function
1100  * @par: Driver data
1101  *
1102  * Uses par->init_sequence to do the initialization
1103  *
1104  * Return: 0 if successful, negative if error
1105  */
1106 int fbtft_init_display(struct fbtft_par *par)
1107 {
1108         int buf[64];
1109         char msg[128];
1110         char str[16];
1111         int i = 0;
1112         int j;
1113
1114         /* sanity check */
1115         if (!par->init_sequence) {
1116                 dev_err(par->info->device,
1117                         "error: init_sequence is not set\n");
1118                 return -EINVAL;
1119         }
1120
1121         /* make sure stop marker exists */
1122         for (i = 0; i < FBTFT_MAX_INIT_SEQUENCE; i++)
1123                 if (par->init_sequence[i] == -3)
1124                         break;
1125         if (i == FBTFT_MAX_INIT_SEQUENCE) {
1126                 dev_err(par->info->device,
1127                         "missing stop marker at end of init sequence\n");
1128                 return -EINVAL;
1129         }
1130
1131         par->fbtftops.reset(par);
1132         if (par->gpio.cs != -1)
1133                 gpio_set_value(par->gpio.cs, 0);  /* Activate chip */
1134
1135         i = 0;
1136         while (i < FBTFT_MAX_INIT_SEQUENCE) {
1137                 if (par->init_sequence[i] == -3) {
1138                         /* done */
1139                         return 0;
1140                 }
1141                 if (par->init_sequence[i] >= 0) {
1142                         dev_err(par->info->device,
1143                                 "missing delimiter at position %d\n", i);
1144                         return -EINVAL;
1145                 }
1146                 if (par->init_sequence[i + 1] < 0) {
1147                         dev_err(par->info->device,
1148                                 "missing value after delimiter %d at position %d\n",
1149                                 par->init_sequence[i], i);
1150                         return -EINVAL;
1151                 }
1152                 switch (par->init_sequence[i]) {
1153                 case -1:
1154                         i++;
1155                         /* make debug message */
1156                         strcpy(msg, "");
1157                         j = i + 1;
1158                         while (par->init_sequence[j] >= 0) {
1159                                 sprintf(str, "0x%02X ", par->init_sequence[j]);
1160                                 strcat(msg, str);
1161                                 j++;
1162                         }
1163                         fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
1164                                       "init: write(0x%02X) %s\n",
1165                                       par->init_sequence[i], msg);
1166
1167                         /* Write */
1168                         j = 0;
1169                         while (par->init_sequence[i] >= 0) {
1170                                 if (j > 63) {
1171                                         dev_err(par->info->device,
1172                                                 "%s: Maximum register values exceeded\n",
1173                                                 __func__);
1174                                         return -EINVAL;
1175                                 }
1176                                 buf[j++] = par->init_sequence[i++];
1177                         }
1178                         par->fbtftops.write_register(par, j,
1179                                 buf[0], buf[1], buf[2], buf[3],
1180                                 buf[4], buf[5], buf[6], buf[7],
1181                                 buf[8], buf[9], buf[10], buf[11],
1182                                 buf[12], buf[13], buf[14], buf[15],
1183                                 buf[16], buf[17], buf[18], buf[19],
1184                                 buf[20], buf[21], buf[22], buf[23],
1185                                 buf[24], buf[25], buf[26], buf[27],
1186                                 buf[28], buf[29], buf[30], buf[31],
1187                                 buf[32], buf[33], buf[34], buf[35],
1188                                 buf[36], buf[37], buf[38], buf[39],
1189                                 buf[40], buf[41], buf[42], buf[43],
1190                                 buf[44], buf[45], buf[46], buf[47],
1191                                 buf[48], buf[49], buf[50], buf[51],
1192                                 buf[52], buf[53], buf[54], buf[55],
1193                                 buf[56], buf[57], buf[58], buf[59],
1194                                 buf[60], buf[61], buf[62], buf[63]);
1195                         break;
1196                 case -2:
1197                         i++;
1198                         fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
1199                                       "init: mdelay(%d)\n",
1200                                       par->init_sequence[i]);
1201                         mdelay(par->init_sequence[i++]);
1202                         break;
1203                 default:
1204                         dev_err(par->info->device,
1205                                 "unknown delimiter %d at position %d\n",
1206                                 par->init_sequence[i], i);
1207                         return -EINVAL;
1208                 }
1209         }
1210
1211         dev_err(par->info->device,
1212                 "%s: something is wrong. Shouldn't get here.\n", __func__);
1213         return -EINVAL;
1214 }
1215 EXPORT_SYMBOL(fbtft_init_display);
1216
1217 /**
1218  * fbtft_verify_gpios() - Generic verify_gpios() function
1219  * @par: Driver data
1220  *
1221  * Uses @spi, @pdev and @buswidth to determine which GPIOs is needed
1222  *
1223  * Return: 0 if successful, negative if error
1224  */
1225 static int fbtft_verify_gpios(struct fbtft_par *par)
1226 {
1227         struct fbtft_platform_data *pdata = par->pdata;
1228         int i;
1229
1230         fbtft_par_dbg(DEBUG_VERIFY_GPIOS, par, "%s()\n", __func__);
1231
1232         if (pdata->display.buswidth != 9 &&  par->startbyte == 0 &&
1233             par->gpio.dc < 0) {
1234                 dev_err(par->info->device,
1235                         "Missing info about 'dc' gpio. Aborting.\n");
1236                 return -EINVAL;
1237         }
1238
1239         if (!par->pdev)
1240                 return 0;
1241
1242         if (par->gpio.wr < 0) {
1243                 dev_err(par->info->device, "Missing 'wr' gpio. Aborting.\n");
1244                 return -EINVAL;
1245         }
1246         for (i = 0; i < pdata->display.buswidth; i++) {
1247                 if (par->gpio.db[i] < 0) {
1248                         dev_err(par->info->device,
1249                                 "Missing 'db%02d' gpio. Aborting.\n", i);
1250                         return -EINVAL;
1251                 }
1252         }
1253
1254         return 0;
1255 }
1256
1257 #ifdef CONFIG_OF
1258 /* returns 0 if the property is not present */
1259 static u32 fbtft_of_value(struct device_node *node, const char *propname)
1260 {
1261         int ret;
1262         u32 val = 0;
1263
1264         ret = of_property_read_u32(node, propname, &val);
1265         if (ret == 0)
1266                 pr_info("%s: %s = %u\n", __func__, propname, val);
1267
1268         return val;
1269 }
1270
1271 static struct fbtft_platform_data *fbtft_probe_dt(struct device *dev)
1272 {
1273         struct device_node *node = dev->of_node;
1274         struct fbtft_platform_data *pdata;
1275
1276         if (!node) {
1277                 dev_err(dev, "Missing platform data or DT\n");
1278                 return ERR_PTR(-EINVAL);
1279         }
1280
1281         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
1282         if (!pdata)
1283                 return ERR_PTR(-ENOMEM);
1284
1285         pdata->display.width = fbtft_of_value(node, "width");
1286         pdata->display.height = fbtft_of_value(node, "height");
1287         pdata->display.regwidth = fbtft_of_value(node, "regwidth");
1288         pdata->display.buswidth = fbtft_of_value(node, "buswidth");
1289         pdata->display.backlight = fbtft_of_value(node, "backlight");
1290         pdata->display.bpp = fbtft_of_value(node, "bpp");
1291         pdata->display.debug = fbtft_of_value(node, "debug");
1292         pdata->rotate = fbtft_of_value(node, "rotate");
1293         pdata->bgr = of_property_read_bool(node, "bgr");
1294         pdata->fps = fbtft_of_value(node, "fps");
1295         pdata->txbuflen = fbtft_of_value(node, "txbuflen");
1296         pdata->startbyte = fbtft_of_value(node, "startbyte");
1297         of_property_read_string(node, "gamma", (const char **)&pdata->gamma);
1298
1299         if (of_find_property(node, "led-gpios", NULL))
1300                 pdata->display.backlight = 1;
1301         if (of_find_property(node, "init", NULL))
1302                 pdata->display.fbtftops.init_display = fbtft_init_display_dt;
1303         pdata->display.fbtftops.request_gpios = fbtft_request_gpios_dt;
1304
1305         return pdata;
1306 }
1307 #else
1308 static struct fbtft_platform_data *fbtft_probe_dt(struct device *dev)
1309 {
1310         dev_err(dev, "Missing platform data\n");
1311         return ERR_PTR(-EINVAL);
1312 }
1313 #endif
1314
1315 /**
1316  * fbtft_probe_common() - Generic device probe() helper function
1317  * @display: Display properties
1318  * @sdev: SPI device
1319  * @pdev: Platform device
1320  *
1321  * Allocates, initializes and registers a framebuffer
1322  *
1323  * Either @sdev or @pdev should be NULL
1324  *
1325  * Return: 0 if successful, negative if error
1326  */
1327 int fbtft_probe_common(struct fbtft_display *display,
1328                        struct spi_device *sdev,
1329                        struct platform_device *pdev)
1330 {
1331         struct device *dev;
1332         struct fb_info *info;
1333         struct fbtft_par *par;
1334         struct fbtft_platform_data *pdata;
1335         int ret;
1336
1337         if (sdev)
1338                 dev = &sdev->dev;
1339         else
1340                 dev = &pdev->dev;
1341
1342         if (unlikely(display->debug & DEBUG_DRIVER_INIT_FUNCTIONS))
1343                 dev_info(dev, "%s()\n", __func__);
1344
1345         pdata = dev->platform_data;
1346         if (!pdata) {
1347                 pdata = fbtft_probe_dt(dev);
1348                 if (IS_ERR(pdata))
1349                         return PTR_ERR(pdata);
1350         }
1351
1352         info = fbtft_framebuffer_alloc(display, dev, pdata);
1353         if (!info)
1354                 return -ENOMEM;
1355
1356         par = info->par;
1357         par->spi = sdev;
1358         par->pdev = pdev;
1359
1360         if (display->buswidth == 0) {
1361                 dev_err(dev, "buswidth is not set\n");
1362                 return -EINVAL;
1363         }
1364
1365         /* write register functions */
1366         if (display->regwidth == 8 && display->buswidth == 8)
1367                 par->fbtftops.write_register = fbtft_write_reg8_bus8;
1368         else if (display->regwidth == 8 && display->buswidth == 9 && par->spi)
1369                 par->fbtftops.write_register = fbtft_write_reg8_bus9;
1370         else if (display->regwidth == 16 && display->buswidth == 8)
1371                 par->fbtftops.write_register = fbtft_write_reg16_bus8;
1372         else if (display->regwidth == 16 && display->buswidth == 16)
1373                 par->fbtftops.write_register = fbtft_write_reg16_bus16;
1374         else
1375                 dev_warn(dev,
1376                          "no default functions for regwidth=%d and buswidth=%d\n",
1377                          display->regwidth, display->buswidth);
1378
1379         /* write_vmem() functions */
1380         if (display->buswidth == 8)
1381                 par->fbtftops.write_vmem = fbtft_write_vmem16_bus8;
1382         else if (display->buswidth == 9)
1383                 par->fbtftops.write_vmem = fbtft_write_vmem16_bus9;
1384         else if (display->buswidth == 16)
1385                 par->fbtftops.write_vmem = fbtft_write_vmem16_bus16;
1386
1387         /* GPIO write() functions */
1388         if (par->pdev) {
1389                 if (display->buswidth == 8)
1390                         par->fbtftops.write = fbtft_write_gpio8_wr;
1391                 else if (display->buswidth == 16)
1392                         par->fbtftops.write = fbtft_write_gpio16_wr;
1393         }
1394
1395         /* 9-bit SPI setup */
1396         if (par->spi && display->buswidth == 9) {
1397                 if (par->spi->master->bits_per_word_mask & SPI_BPW_MASK(9)) {
1398                         par->spi->bits_per_word = 9;
1399                 } else {
1400                         dev_warn(&par->spi->dev,
1401                                  "9-bit SPI not available, emulating using 8-bit.\n");
1402                         /* allocate buffer with room for dc bits */
1403                         par->extra = devm_kzalloc(par->info->device,
1404                                                   par->txbuf.len +
1405                                                   (par->txbuf.len / 8) + 8,
1406                                                   GFP_KERNEL);
1407                         if (!par->extra) {
1408                                 ret = -ENOMEM;
1409                                 goto out_release;
1410                         }
1411                         par->fbtftops.write = fbtft_write_spi_emulate_9;
1412                 }
1413         }
1414
1415         if (!par->fbtftops.verify_gpios)
1416                 par->fbtftops.verify_gpios = fbtft_verify_gpios;
1417
1418         /* make sure we still use the driver provided functions */
1419         fbtft_merge_fbtftops(&par->fbtftops, &display->fbtftops);
1420
1421         /* use init_sequence if provided */
1422         if (par->init_sequence)
1423                 par->fbtftops.init_display = fbtft_init_display;
1424
1425         /* use platform_data provided functions above all */
1426         fbtft_merge_fbtftops(&par->fbtftops, &pdata->display.fbtftops);
1427
1428         ret = fbtft_register_framebuffer(info);
1429         if (ret < 0)
1430                 goto out_release;
1431
1432         return 0;
1433
1434 out_release:
1435         fbtft_framebuffer_release(info);
1436
1437         return ret;
1438 }
1439 EXPORT_SYMBOL(fbtft_probe_common);
1440
1441 /**
1442  * fbtft_remove_common() - Generic device remove() helper function
1443  * @dev: Device
1444  * @info: Framebuffer
1445  *
1446  * Unregisters and releases the framebuffer
1447  *
1448  * Return: 0 if successful, negative if error
1449  */
1450 int fbtft_remove_common(struct device *dev, struct fb_info *info)
1451 {
1452         struct fbtft_par *par;
1453
1454         if (!info)
1455                 return -EINVAL;
1456         par = info->par;
1457         if (par)
1458                 fbtft_par_dbg(DEBUG_DRIVER_INIT_FUNCTIONS, par,
1459                               "%s()\n", __func__);
1460         fbtft_unregister_framebuffer(info);
1461         fbtft_framebuffer_release(info);
1462
1463         return 0;
1464 }
1465 EXPORT_SYMBOL(fbtft_remove_common);
1466
1467 MODULE_LICENSE("GPL");