drivers/staging/fbtft/fbtft-core.c

   1 /*
   2  * Copyright (C) 2013 Noralf Tronnes
   3  *
   4  * This driver is inspired by:
   5  *   st7735fb.c, Copyright (C) 2011, Matt Porter
   6  *   broadsheetfb.c, Copyright (C) 2008, Jaya Kumar
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/kernel.h>
  21 #include <linux/errno.h>
  22 #include <linux/string.h>
  23 #include <linux/mm.h>
  24 #include <linux/vmalloc.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/fb.h>
  28 #include <linux/gpio.h>
  29 #include <linux/spi/spi.h>
  30 #include <linux/delay.h>
  31 #include <linux/uaccess.h>
  32 #include <linux/backlight.h>
  33 #include <linux/platform_device.h>
  34 #include <linux/spinlock.h>
  35 #include <linux/dma-mapping.h>
  36 #include <linux/of.h>
  37 #include <linux/of_gpio.h>
  38
  39 #include "fbtft.h"
  40 #include "internal.h"
  41
  42 static unsigned long debug;
  43 module_param(debug, ulong, 0);
  44 MODULE_PARM_DESC(debug, "override device debug level");
  45
  46 #ifdef CONFIG_HAS_DMA
  47 static bool dma = true;
  48 module_param(dma, bool, 0);
  49 MODULE_PARM_DESC(dma, "Use DMA buffer");
  50 #endif
  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         long 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 = kstrtol(&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                 if (par->fbtftops.request_gpios_match)
 134                         flags = par->fbtftops.request_gpios_match(par, gpio);
 135                 if (flags == FBTFT_GPIO_NO_MATCH)
 136                         flags = fbtft_request_gpios_match(par, gpio);
 137                 if (flags != FBTFT_GPIO_NO_MATCH) {
 138                         ret = devm_gpio_request_one(par->info->device,
 139                                         gpio->gpio, flags,
 140                                         par->info->device->driver->name);
 141                         if (ret < 0) {
 142                                 dev_err(par->info->device,
 143                                         "%s: gpio_request_one('%s'=%d) failed with %d\n",
 144                                         __func__, gpio->name,
 145                                         gpio->gpio, ret);
 146                                 return ret;
 147                         }
 148                         fbtft_par_dbg(DEBUG_REQUEST_GPIOS, par,
 149                                 "%s: '%s' = GPIO%d\n",
 150                                 __func__, gpio->name, gpio->gpio);
 151                 }
 152                 gpio++;
 153         }
 154
 155         return 0;
 156 }
 157
 158 #ifdef CONFIG_OF
 159 static int fbtft_request_one_gpio(struct fbtft_par *par,
 160                                   const char *name, int index, int *gpiop)
 161 {
 162         struct device *dev = par->info->device;
 163         struct device_node *node = dev->of_node;
 164         int gpio, flags, ret = 0;
 165         enum of_gpio_flags of_flags;
 166
 167         if (of_find_property(node, name, NULL)) {
 168                 gpio = of_get_named_gpio_flags(node, name, index, &of_flags);
 169                 if (gpio == -ENOENT)
 170                         return 0;
 171                 if (gpio == -EPROBE_DEFER)
 172                         return gpio;
 173                 if (gpio < 0) {
 174                         dev_err(dev,
 175                                 "failed to get '%s' from DT\n", name);
 176                         return gpio;
 177                 }
 178
 179                 /* active low translates to initially low */
 180                 flags = (of_flags & OF_GPIO_ACTIVE_LOW) ? GPIOF_OUT_INIT_LOW :
 181                                                         GPIOF_OUT_INIT_HIGH;
 182                 ret = devm_gpio_request_one(dev, gpio, flags,
 183                                                 dev->driver->name);
 184                 if (ret) {
 185                         dev_err(dev,
 186                                 "gpio_request_one('%s'=%d) failed with %d\n",
 187                                 name, gpio, ret);
 188                         return ret;
 189                 }
 190                 if (gpiop)
 191                         *gpiop = gpio;
 192                 fbtft_par_dbg(DEBUG_REQUEST_GPIOS, par, "%s: '%s' = GPIO%d\n",
 193                                                         __func__, name, gpio);
 194         }
 195
 196         return ret;
 197 }
 198
 199 static int fbtft_request_gpios_dt(struct fbtft_par *par)
 200 {
 201         int i;
 202         int ret;
 203
 204         if (!par->info->device->of_node)
 205                 return -EINVAL;
 206
 207         ret = fbtft_request_one_gpio(par, "reset-gpios", 0, &par->gpio.reset);
 208         if (ret)
 209                 return ret;
 210         ret = fbtft_request_one_gpio(par, "dc-gpios", 0, &par->gpio.dc);
 211         if (ret)
 212                 return ret;
 213         ret = fbtft_request_one_gpio(par, "rd-gpios", 0, &par->gpio.rd);
 214         if (ret)
 215                 return ret;
 216         ret = fbtft_request_one_gpio(par, "wr-gpios", 0, &par->gpio.wr);
 217         if (ret)
 218                 return ret;
 219         ret = fbtft_request_one_gpio(par, "cs-gpios", 0, &par->gpio.cs);
 220         if (ret)
 221                 return ret;
 222         ret = fbtft_request_one_gpio(par, "latch-gpios", 0, &par->gpio.latch);
 223         if (ret)
 224                 return ret;
 225         for (i = 0; i < 16; i++) {
 226                 ret = fbtft_request_one_gpio(par, "db-gpios", i,
 227                                                 &par->gpio.db[i]);
 228                 if (ret)
 229                         return ret;
 230                 ret = fbtft_request_one_gpio(par, "led-gpios", i,
 231                                                 &par->gpio.led[i]);
 232                 if (ret)
 233                         return ret;
 234                 ret = fbtft_request_one_gpio(par, "aux-gpios", i,
 235                                                 &par->gpio.aux[i]);
 236                 if (ret)
 237                         return ret;
 238         }
 239
 240         return 0;
 241 }
 242 #endif
 243
 244 #ifdef CONFIG_FB_BACKLIGHT
 245 static int fbtft_backlight_update_status(struct backlight_device *bd)
 246 {
 247         struct fbtft_par *par = bl_get_data(bd);
 248         bool polarity = !!(bd->props.state & BL_CORE_DRIVER1);
 249
 250         fbtft_par_dbg(DEBUG_BACKLIGHT, par,
 251                 "%s: polarity=%d, power=%d, fb_blank=%d\n",
 252                 __func__, polarity, bd->props.power, bd->props.fb_blank);
 253
 254         if ((bd->props.power == FB_BLANK_UNBLANK) && (bd->props.fb_blank == FB_BLANK_UNBLANK))
 255                 gpio_set_value(par->gpio.led[0], polarity);
 256         else
 257                 gpio_set_value(par->gpio.led[0], !polarity);
 258
 259         return 0;
 260 }
 261
 262 static int fbtft_backlight_get_brightness(struct backlight_device *bd)
 263 {
 264         return bd->props.brightness;
 265 }
 266
 267 void fbtft_unregister_backlight(struct fbtft_par *par)
 268 {
 269         if (par->info->bl_dev) {
 270                 par->info->bl_dev->props.power = FB_BLANK_POWERDOWN;
 271                 backlight_update_status(par->info->bl_dev);
 272                 backlight_device_unregister(par->info->bl_dev);
 273                 par->info->bl_dev = NULL;
 274         }
 275 }
 276
 277 static const struct backlight_ops fbtft_bl_ops = {
 278         .get_brightness = fbtft_backlight_get_brightness,
 279         .update_status  = fbtft_backlight_update_status,
 280 };
 281
 282 void fbtft_register_backlight(struct fbtft_par *par)
 283 {
 284         struct backlight_device *bd;
 285         struct backlight_properties bl_props = { 0, };
 286
 287         if (par->gpio.led[0] == -1) {
 288                 fbtft_par_dbg(DEBUG_BACKLIGHT, par,
 289                         "%s(): led pin not set, exiting.\n", __func__);
 290                 return;
 291         }
 292
 293         bl_props.type = BACKLIGHT_RAW;
 294         /* Assume backlight is off, get polarity from current state of pin */
 295         bl_props.power = FB_BLANK_POWERDOWN;
 296         if (!gpio_get_value(par->gpio.led[0]))
 297                 bl_props.state |= BL_CORE_DRIVER1;
 298
 299         bd = backlight_device_register(dev_driver_string(par->info->device),
 300                                 par->info->device, par, &fbtft_bl_ops, &bl_props);
 301         if (IS_ERR(bd)) {
 302                 dev_err(par->info->device,
 303                         "cannot register backlight device (%ld)\n",
 304                         PTR_ERR(bd));
 305                 return;
 306         }
 307         par->info->bl_dev = bd;
 308
 309         if (!par->fbtftops.unregister_backlight)
 310                 par->fbtftops.unregister_backlight = fbtft_unregister_backlight;
 311 }
 312 #else
 313 void fbtft_register_backlight(struct fbtft_par *par) { };
 314 void fbtft_unregister_backlight(struct fbtft_par *par) { };
 315 #endif
 316 EXPORT_SYMBOL(fbtft_register_backlight);
 317 EXPORT_SYMBOL(fbtft_unregister_backlight);
 318
 319 static void fbtft_set_addr_win(struct fbtft_par *par, int xs, int ys, int xe,
 320                                int ye)
 321 {
 322         /* Column address set */
 323         write_reg(par, 0x2A,
 324                 (xs >> 8) & 0xFF, xs & 0xFF, (xe >> 8) & 0xFF, xe & 0xFF);
 325
 326         /* Row address set */
 327         write_reg(par, 0x2B,
 328                 (ys >> 8) & 0xFF, ys & 0xFF, (ye >> 8) & 0xFF, ye & 0xFF);
 329
 330         /* Memory write */
 331         write_reg(par, 0x2C);
 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(par->gpio.reset, 0);
 340         udelay(20);
 341         gpio_set_value(par->gpio.reset, 1);
 342         mdelay(120);
 343 }
 344
 345 static void fbtft_update_display(struct fbtft_par *par, unsigned start_line,
 346                                  unsigned 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 | DEBUG_TIME_EACH_UPDATE))) {
 355                 if ((par->debug & DEBUG_TIME_EACH_UPDATE) ||
 356                                 ((par->debug & DEBUG_TIME_FIRST_UPDATE) && !par->first_update_done)) {
 357                         ts_start = ktime_get();
 358                         timeit = true;
 359                 }
 360         }
 361
 362         /* Sanity checks */
 363         if (start_line > end_line) {
 364                 dev_warn(par->info->device,
 365                         "%s: start_line=%u is larger than end_line=%u. Shouldn't happen, will do full display update\n",
 366                         __func__, start_line, end_line);
 367                 start_line = 0;
 368                 end_line = par->info->var.yres - 1;
 369         }
 370         if (start_line > par->info->var.yres - 1 || end_line > par->info->var.yres - 1) {
 371                 dev_warn(par->info->device,
 372                         "%s: start_line=%u or end_line=%u is larger than max=%d. Shouldn't happen, will do full display update\n",
 373                         __func__, start_line, end_line, par->info->var.yres - 1);
 374                 start_line = 0;
 375                 end_line = par->info->var.yres - 1;
 376         }
 377
 378         fbtft_par_dbg(DEBUG_UPDATE_DISPLAY, par, "%s(start_line=%u, end_line=%u)\n",
 379                 __func__, start_line, end_line);
 380
 381         if (par->fbtftops.set_addr_win)
 382                 par->fbtftops.set_addr_win(par, 0, start_line,
 383                                 par->info->var.xres - 1, end_line);
 384
 385         offset = start_line * par->info->fix.line_length;
 386         len = (end_line - start_line + 1) * par->info->fix.line_length;
 387         ret = par->fbtftops.write_vmem(par, offset, len);
 388         if (ret < 0)
 389                 dev_err(par->info->device,
 390                         "%s: write_vmem failed to update display buffer\n",
 391                         __func__);
 392
 393         if (unlikely(timeit)) {
 394                 ts_end = ktime_get();
 395                 if (!ktime_to_ns(par->update_time))
 396                         par->update_time = ts_start;
 397
 398                 fps = ktime_us_delta(ts_start, par->update_time);
 399                 par->update_time = ts_start;
 400                 fps = fps ? 1000000 / fps : 0;
 401
 402                 throughput = ktime_us_delta(ts_end, ts_start);
 403                 throughput = throughput ? (len * 1000) / throughput : 0;
 404                 throughput = throughput * 1000 / 1024;
 405
 406                 dev_info(par->info->device,
 407                         "Display update: %ld kB/s, fps=%ld\n",
 408                         throughput, fps);
 409                 par->first_update_done = true;
 410         }
 411 }
 412
 413 static void fbtft_mkdirty(struct fb_info *info, int y, int height)
 414 {
 415         struct fbtft_par *par = info->par;
 416         struct fb_deferred_io *fbdefio = info->fbdefio;
 417
 418         /* special case, needed ? */
 419         if (y == -1) {
 420                 y = 0;
 421                 height = info->var.yres - 1;
 422         }
 423
 424         /* Mark display lines/area as dirty */
 425         spin_lock(&par->dirty_lock);
 426         if (y < par->dirty_lines_start)
 427                 par->dirty_lines_start = y;
 428         if (y + height - 1 > par->dirty_lines_end)
 429                 par->dirty_lines_end = y + height - 1;
 430         spin_unlock(&par->dirty_lock);
 431
 432         /* Schedule deferred_io to update display (no-op if already on queue)*/
 433         schedule_delayed_work(&info->deferred_work, fbdefio->delay);
 434 }
 435
 436 static void fbtft_deferred_io(struct fb_info *info, struct list_head *pagelist)
 437 {
 438         struct fbtft_par *par = info->par;
 439         unsigned dirty_lines_start, dirty_lines_end;
 440         struct page *page;
 441         unsigned long index;
 442         unsigned y_low = 0, y_high = 0;
 443         int count = 0;
 444
 445         spin_lock(&par->dirty_lock);
 446         dirty_lines_start = par->dirty_lines_start;
 447         dirty_lines_end = par->dirty_lines_end;
 448         /* set display line markers as clean */
 449         par->dirty_lines_start = par->info->var.yres - 1;
 450         par->dirty_lines_end = 0;
 451         spin_unlock(&par->dirty_lock);
 452
 453         /* Mark display lines as dirty */
 454         list_for_each_entry(page, pagelist, lru) {
 455                 count++;
 456                 index = page->index << PAGE_SHIFT;
 457                 y_low = index / info->fix.line_length;
 458                 y_high = (index + PAGE_SIZE - 1) / info->fix.line_length;
 459                 dev_dbg(info->device,
 460                         "page->index=%lu y_low=%d y_high=%d\n",
 461                         page->index, y_low, y_high);
 462                 if (y_high > info->var.yres - 1)
 463                         y_high = info->var.yres - 1;
 464                 if (y_low < dirty_lines_start)
 465                         dirty_lines_start = y_low;
 466                 if (y_high > dirty_lines_end)
 467                         dirty_lines_end = y_high;
 468         }
 469
 470         par->fbtftops.update_display(info->par,
 471                                         dirty_lines_start, dirty_lines_end);
 472 }
 473
 474 static void fbtft_fb_fillrect(struct fb_info *info,
 475                               const struct fb_fillrect *rect)
 476 {
 477         struct fbtft_par *par = info->par;
 478
 479         dev_dbg(info->dev,
 480                 "%s: dx=%d, dy=%d, width=%d, height=%d\n",
 481                 __func__, rect->dx, rect->dy, rect->width, rect->height);
 482         sys_fillrect(info, rect);
 483
 484         par->fbtftops.mkdirty(info, rect->dy, rect->height);
 485 }
 486
 487 static void fbtft_fb_copyarea(struct fb_info *info,
 488                               const struct fb_copyarea *area)
 489 {
 490         struct fbtft_par *par = info->par;
 491
 492         dev_dbg(info->dev,
 493                 "%s: dx=%d, dy=%d, width=%d, height=%d\n",
 494                 __func__,  area->dx, area->dy, area->width, area->height);
 495         sys_copyarea(info, area);
 496
 497         par->fbtftops.mkdirty(info, area->dy, area->height);
 498 }
 499
 500 static void fbtft_fb_imageblit(struct fb_info *info,
 501                                const struct fb_image *image)
 502 {
 503         struct fbtft_par *par = info->par;
 504
 505         dev_dbg(info->dev,
 506                 "%s: dx=%d, dy=%d, width=%d, height=%d\n",
 507                 __func__,  image->dx, image->dy, image->width, image->height);
 508         sys_imageblit(info, image);
 509
 510         par->fbtftops.mkdirty(info, image->dy, image->height);
 511 }
 512
 513 static ssize_t fbtft_fb_write(struct fb_info *info, const char __user *buf,
 514                               size_t count, loff_t *ppos)
 515 {
 516         struct fbtft_par *par = info->par;
 517         ssize_t res;
 518
 519         dev_dbg(info->dev,
 520                 "%s: count=%zd, ppos=%llu\n", __func__,  count, *ppos);
 521         res = fb_sys_write(info, buf, count, ppos);
 522
 523         /* TODO: only mark changed area
 524            update all for now */
 525         par->fbtftops.mkdirty(info, -1, 0);
 526
 527         return res;
 528 }
 529
 530 /* from pxafb.c */
 531 static unsigned int chan_to_field(unsigned chan, struct fb_bitfield *bf)
 532 {
 533         chan &= 0xffff;
 534         chan >>= 16 - bf->length;
 535         return chan << bf->offset;
 536 }
 537
 538 static int fbtft_fb_setcolreg(unsigned regno, unsigned red, unsigned green,
 539                               unsigned blue, unsigned transp,
 540                               struct fb_info *info)
 541 {
 542         unsigned val;
 543         int ret = 1;
 544
 545         dev_dbg(info->dev,
 546                 "%s(regno=%u, red=0x%X, green=0x%X, blue=0x%X, trans=0x%X)\n",
 547                 __func__, regno, red, green, blue, transp);
 548
 549         switch (info->fix.visual) {
 550         case FB_VISUAL_TRUECOLOR:
 551                 if (regno < 16) {
 552                         u32 *pal = info->pseudo_palette;
 553
 554                         val  = chan_to_field(red,   &info->var.red);
 555                         val |= chan_to_field(green, &info->var.green);
 556                         val |= chan_to_field(blue,  &info->var.blue);
 557
 558                         pal[regno] = val;
 559                         ret = 0;
 560                 }
 561                 break;
 562
 563         }
 564         return ret;
 565 }
 566
 567 static int fbtft_fb_blank(int blank, struct fb_info *info)
 568 {
 569         struct fbtft_par *par = info->par;
 570         int ret = -EINVAL;
 571
 572         dev_dbg(info->dev, "%s(blank=%d)\n",
 573                 __func__, blank);
 574
 575         if (!par->fbtftops.blank)
 576                 return ret;
 577
 578         switch (blank) {
 579         case FB_BLANK_POWERDOWN:
 580         case FB_BLANK_VSYNC_SUSPEND:
 581         case FB_BLANK_HSYNC_SUSPEND:
 582         case FB_BLANK_NORMAL:
 583                 ret = par->fbtftops.blank(par, true);
 584                 break;
 585         case FB_BLANK_UNBLANK:
 586                 ret = par->fbtftops.blank(par, false);
 587                 break;
 588         }
 589         return ret;
 590 }
 591
 592 static void fbtft_merge_fbtftops(struct fbtft_ops *dst, struct fbtft_ops *src)
 593 {
 594         if (src->write)
 595                 dst->write = src->write;
 596         if (src->read)
 597                 dst->read = src->read;
 598         if (src->write_vmem)
 599                 dst->write_vmem = src->write_vmem;
 600         if (src->write_register)
 601                 dst->write_register = src->write_register;
 602         if (src->set_addr_win)
 603                 dst->set_addr_win = src->set_addr_win;
 604         if (src->reset)
 605                 dst->reset = src->reset;
 606         if (src->mkdirty)
 607                 dst->mkdirty = src->mkdirty;
 608         if (src->update_display)
 609                 dst->update_display = src->update_display;
 610         if (src->init_display)
 611                 dst->init_display = src->init_display;
 612         if (src->blank)
 613                 dst->blank = src->blank;
 614         if (src->request_gpios_match)
 615                 dst->request_gpios_match = src->request_gpios_match;
 616         if (src->request_gpios)
 617                 dst->request_gpios = src->request_gpios;
 618         if (src->verify_gpios)
 619                 dst->verify_gpios = src->verify_gpios;
 620         if (src->register_backlight)
 621                 dst->register_backlight = src->register_backlight;
 622         if (src->unregister_backlight)
 623                 dst->unregister_backlight = src->unregister_backlight;
 624         if (src->set_var)
 625                 dst->set_var = src->set_var;
 626         if (src->set_gamma)
 627                 dst->set_gamma = src->set_gamma;
 628 }
 629
 630 /**
 631  * fbtft_framebuffer_alloc - creates a new frame buffer info structure
 632  *
 633  * @display: pointer to structure describing the display
 634  * @dev: pointer to the device for this fb, this can be NULL
 635  *
 636  * Creates a new frame buffer info structure.
 637  *
 638  * Also creates and populates the following structures:
 639  *   info->fbops
 640  *   info->fbdefio
 641  *   info->pseudo_palette
 642  *   par->fbtftops
 643  *   par->txbuf
 644  *
 645  * Returns the new structure, or NULL if an error occurred.
 646  *
 647  */
 648 struct fb_info *fbtft_framebuffer_alloc(struct fbtft_display *display,
 649                                         struct device *dev,
 650                                         struct fbtft_platform_data *pdata)
 651 {
 652         struct fb_info *info;
 653         struct fbtft_par *par;
 654         struct fb_ops *fbops = NULL;
 655         struct fb_deferred_io *fbdefio = NULL;
 656         u8 *vmem = NULL;
 657         void *txbuf = NULL;
 658         void *buf = NULL;
 659         unsigned width;
 660         unsigned height;
 661         int txbuflen = display->txbuflen;
 662         unsigned bpp = display->bpp;
 663         unsigned fps = display->fps;
 664         int vmem_size, i;
 665         int *init_sequence = display->init_sequence;
 666         char *gamma = display->gamma;
 667         unsigned long *gamma_curves = NULL;
 668
 669         /* sanity check */
 670         if (display->gamma_num * display->gamma_len > FBTFT_GAMMA_MAX_VALUES_TOTAL) {
 671                 dev_err(dev, "FBTFT_GAMMA_MAX_VALUES_TOTAL=%d is exceeded\n",
 672                         FBTFT_GAMMA_MAX_VALUES_TOTAL);
 673                 return NULL;
 674         }
 675
 676         /* defaults */
 677         if (!fps)
 678                 fps = 20;
 679         if (!bpp)
 680                 bpp = 16;
 681
 682         if (!pdata) {
 683                 dev_err(dev, "platform data is missing\n");
 684                 return NULL;
 685         }
 686
 687         /* override driver values? */
 688         if (pdata->fps)
 689                 fps = pdata->fps;
 690         if (pdata->txbuflen)
 691                 txbuflen = pdata->txbuflen;
 692         if (pdata->display.init_sequence)
 693                 init_sequence = pdata->display.init_sequence;
 694         if (pdata->gamma)
 695                 gamma = pdata->gamma;
 696         if (pdata->display.debug)
 697                 display->debug = pdata->display.debug;
 698         if (pdata->display.backlight)
 699                 display->backlight = pdata->display.backlight;
 700         if (pdata->display.width)
 701                 display->width = pdata->display.width;
 702         if (pdata->display.height)
 703                 display->height = pdata->display.height;
 704         if (pdata->display.buswidth)
 705                 display->buswidth = pdata->display.buswidth;
 706         if (pdata->display.regwidth)
 707                 display->regwidth = pdata->display.regwidth;
 708
 709         display->debug |= debug;
 710         fbtft_expand_debug_value(&display->debug);
 711
 712         switch (pdata->rotate) {
 713         case 90:
 714         case 270:
 715                 width =  display->height;
 716                 height = display->width;
 717                 break;
 718         default:
 719                 width =  display->width;
 720                 height = display->height;
 721         }
 722
 723         vmem_size = display->width * display->height * bpp / 8;
 724         vmem = vzalloc(vmem_size);
 725         if (!vmem)
 726                 goto alloc_fail;
 727
 728         fbops = devm_kzalloc(dev, sizeof(struct fb_ops), GFP_KERNEL);
 729         if (!fbops)
 730                 goto alloc_fail;
 731
 732         fbdefio = devm_kzalloc(dev, sizeof(struct fb_deferred_io), GFP_KERNEL);
 733         if (!fbdefio)
 734                 goto alloc_fail;
 735
 736         buf = devm_kzalloc(dev, 128, GFP_KERNEL);
 737         if (!buf)
 738                 goto alloc_fail;
 739
 740         if (display->gamma_num && display->gamma_len) {
 741                 gamma_curves = devm_kzalloc(dev, display->gamma_num * display->gamma_len * sizeof(gamma_curves[0]),
 742                                                 GFP_KERNEL);
 743                 if (!gamma_curves)
 744                         goto alloc_fail;
 745         }
 746
 747         info = framebuffer_alloc(sizeof(struct fbtft_par), dev);
 748         if (!info)
 749                 goto alloc_fail;
 750
 751         info->screen_buffer = vmem;
 752         info->fbops = fbops;
 753         info->fbdefio = fbdefio;
 754
 755         fbops->owner        =      dev->driver->owner;
 756         fbops->fb_read      =      fb_sys_read;
 757         fbops->fb_write     =      fbtft_fb_write;
 758         fbops->fb_fillrect  =      fbtft_fb_fillrect;
 759         fbops->fb_copyarea  =      fbtft_fb_copyarea;
 760         fbops->fb_imageblit =      fbtft_fb_imageblit;
 761         fbops->fb_setcolreg =      fbtft_fb_setcolreg;
 762         fbops->fb_blank     =      fbtft_fb_blank;
 763
 764         fbdefio->delay =           HZ/fps;
 765         fbdefio->deferred_io =     fbtft_deferred_io;
 766         fb_deferred_io_init(info);
 767
 768         snprintf(info->fix.id, sizeof(info->fix.id), "%s", dev->driver->name);
 769         info->fix.type =           FB_TYPE_PACKED_PIXELS;
 770         info->fix.visual =         FB_VISUAL_TRUECOLOR;
 771         info->fix.xpanstep =       0;
 772         info->fix.ypanstep =       0;
 773         info->fix.ywrapstep =      0;
 774         info->fix.line_length =    width * bpp / 8;
 775         info->fix.accel =          FB_ACCEL_NONE;
 776         info->fix.smem_len =       vmem_size;
 777
 778         info->var.rotate =         pdata->rotate;
 779         info->var.xres =           width;
 780         info->var.yres =           height;
 781         info->var.xres_virtual =   info->var.xres;
 782         info->var.yres_virtual =   info->var.yres;
 783         info->var.bits_per_pixel = bpp;
 784         info->var.nonstd =         1;
 785
 786         /* RGB565 */
 787         info->var.red.offset =     11;
 788         info->var.red.length =     5;
 789         info->var.green.offset =   5;
 790         info->var.green.length =   6;
 791         info->var.blue.offset =    0;
 792         info->var.blue.length =    5;
 793         info->var.transp.offset =  0;
 794         info->var.transp.length =  0;
 795
 796         info->flags =              FBINFO_FLAG_DEFAULT | FBINFO_VIRTFB;
 797
 798         par = info->par;
 799         par->info = info;
 800         par->pdata = pdata;
 801         par->debug = display->debug;
 802         par->buf = buf;
 803         spin_lock_init(&par->dirty_lock);
 804         par->bgr = pdata->bgr;
 805         par->startbyte = pdata->startbyte;
 806         par->init_sequence = init_sequence;
 807         par->gamma.curves = gamma_curves;
 808         par->gamma.num_curves = display->gamma_num;
 809         par->gamma.num_values = display->gamma_len;
 810         mutex_init(&par->gamma.lock);
 811         info->pseudo_palette = par->pseudo_palette;
 812
 813         if (par->gamma.curves && gamma) {
 814                 if (fbtft_gamma_parse_str(par,
 815                         par->gamma.curves, gamma, strlen(gamma)))
 816                         goto release_framebuf;
 817         }
 818
 819         /* Transmit buffer */
 820         if (txbuflen == -1)
 821                 txbuflen = vmem_size + 2; /* add in case startbyte is used */
 822
 823 #ifdef __LITTLE_ENDIAN
 824         if ((!txbuflen) && (bpp > 8))
 825                 txbuflen = PAGE_SIZE; /* need buffer for byteswapping */
 826 #endif
 827
 828         if (txbuflen > 0) {
 829 #ifdef CONFIG_HAS_DMA
 830                 if (dma) {
 831                         dev->coherent_dma_mask = ~0;
 832                         txbuf = dmam_alloc_coherent(dev, txbuflen, &par->txbuf.dma, GFP_DMA);
 833                 } else
 834 #endif
 835                 {
 836                         txbuf = devm_kzalloc(par->info->device, txbuflen, GFP_KERNEL);
 837                 }
 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)
 969                 sprintf(text1, ", %zu KiB %sbuffer memory",
 970                         par->txbuf.len >> 10, par->txbuf.dma ? "DMA " : "");
 971         if (spi)
 972                 sprintf(text2, ", spi%d.%d at %d MHz", spi->master->bus_num,
 973                         spi->chip_select, spi->max_speed_hz / 1000000);
 974         dev_info(fb_info->dev,
 975                 "%s frame buffer, %dx%d, %d KiB video memory%s, fps=%lu%s\n",
 976                 fb_info->fix.id, fb_info->var.xres, fb_info->var.yres,
 977                 fb_info->fix.smem_len >> 10, text1,
 978                 HZ / fb_info->fbdefio->delay, text2);
 979
 980 #ifdef CONFIG_FB_BACKLIGHT
 981         /* Turn on backlight if available */
 982         if (fb_info->bl_dev) {
 983                 fb_info->bl_dev->props.power = FB_BLANK_UNBLANK;
 984                 fb_info->bl_dev->ops->update_status(fb_info->bl_dev);
 985         }
 986 #endif
 987
 988         return 0;
 989
 990 reg_fail:
 991         if (par->fbtftops.unregister_backlight)
 992                 par->fbtftops.unregister_backlight(par);
 993         if (spi)
 994                 spi_set_drvdata(spi, NULL);
 995         if (par->pdev)
 996                 platform_set_drvdata(par->pdev, NULL);
 997
 998         return ret;
 999 }
1000 EXPORT_SYMBOL(fbtft_register_framebuffer);
1001
1002 /**
1003  *      fbtft_unregister_framebuffer - releases a tft frame buffer device
1004  *      @fb_info: frame buffer info structure
1005  *
1006  *  Frees SPI driverdata if needed
1007  *  Frees gpios.
1008  *      Unregisters frame buffer device.
1009  *
1010  */
1011 int fbtft_unregister_framebuffer(struct fb_info *fb_info)
1012 {
1013         struct fbtft_par *par = fb_info->par;
1014         struct spi_device *spi = par->spi;
1015
1016         if (spi)
1017                 spi_set_drvdata(spi, NULL);
1018         if (par->pdev)
1019                 platform_set_drvdata(par->pdev, NULL);
1020         if (par->fbtftops.unregister_backlight)
1021                 par->fbtftops.unregister_backlight(par);
1022         fbtft_sysfs_exit(par);
1023         return unregister_framebuffer(fb_info);
1024 }
1025 EXPORT_SYMBOL(fbtft_unregister_framebuffer);
1026
1027 #ifdef CONFIG_OF
1028 /**
1029  * fbtft_init_display_dt() - Device Tree init_display() function
1030  * @par: Driver data
1031  *
1032  * Return: 0 if successful, negative if error
1033  */
1034 static int fbtft_init_display_dt(struct fbtft_par *par)
1035 {
1036         struct device_node *node = par->info->device->of_node;
1037         struct property *prop;
1038         const __be32 *p;
1039         u32 val;
1040         int buf[64], i, j;
1041
1042         if (!node)
1043                 return -EINVAL;
1044
1045         prop = of_find_property(node, "init", NULL);
1046         p = of_prop_next_u32(prop, NULL, &val);
1047         if (!p)
1048                 return -EINVAL;
1049
1050         par->fbtftops.reset(par);
1051         if (par->gpio.cs != -1)
1052                 gpio_set_value(par->gpio.cs, 0);  /* Activate chip */
1053
1054         while (p) {
1055                 if (val & FBTFT_OF_INIT_CMD) {
1056                         val &= 0xFFFF;
1057                         i = 0;
1058                         while (p && !(val & 0xFFFF0000)) {
1059                                 if (i > 63) {
1060                                         dev_err(par->info->device,
1061                                         "%s: Maximum register values exceeded\n",
1062                                         __func__);
1063                                         return -EINVAL;
1064                                 }
1065                                 buf[i++] = val;
1066                                 p = of_prop_next_u32(prop, p, &val);
1067                         }
1068                         /* make debug message */
1069                         fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
1070                                 "init: write_register:\n");
1071                         for (j = 0; j < i; j++)
1072                                 fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
1073                                               "buf[%d] = %02X\n", j, buf[j]);
1074
1075                         par->fbtftops.write_register(par, i,
1076                                 buf[0], buf[1], buf[2], buf[3],
1077                                 buf[4], buf[5], buf[6], buf[7],
1078                                 buf[8], buf[9], buf[10], buf[11],
1079                                 buf[12], buf[13], buf[14], buf[15],
1080                                 buf[16], buf[17], buf[18], buf[19],
1081                                 buf[20], buf[21], buf[22], buf[23],
1082                                 buf[24], buf[25], buf[26], buf[27],
1083                                 buf[28], buf[29], buf[30], buf[31],
1084                                 buf[32], buf[33], buf[34], buf[35],
1085                                 buf[36], buf[37], buf[38], buf[39],
1086                                 buf[40], buf[41], buf[42], buf[43],
1087                                 buf[44], buf[45], buf[46], buf[47],
1088                                 buf[48], buf[49], buf[50], buf[51],
1089                                 buf[52], buf[53], buf[54], buf[55],
1090                                 buf[56], buf[57], buf[58], buf[59],
1091                                 buf[60], buf[61], buf[62], buf[63]);
1092                 } else if (val & FBTFT_OF_INIT_DELAY) {
1093                         fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
1094                                 "init: msleep(%u)\n", val & 0xFFFF);
1095                         msleep(val & 0xFFFF);
1096                         p = of_prop_next_u32(prop, p, &val);
1097                 } else {
1098                         dev_err(par->info->device, "illegal init value 0x%X\n",
1099                                                                         val);
1100                         return -EINVAL;
1101                 }
1102         }
1103
1104         return 0;
1105 }
1106 #endif
1107
1108 /**
1109  * fbtft_init_display() - Generic init_display() function
1110  * @par: Driver data
1111  *
1112  * Uses par->init_sequence to do the initialization
1113  *
1114  * Return: 0 if successful, negative if error
1115  */
1116 int fbtft_init_display(struct fbtft_par *par)
1117 {
1118         int buf[64];
1119         char msg[128];
1120         char str[16];
1121         int i = 0;
1122         int j;
1123
1124         /* sanity check */
1125         if (!par->init_sequence) {
1126                 dev_err(par->info->device,
1127                         "error: init_sequence is not set\n");
1128                 return -EINVAL;
1129         }
1130
1131         /* make sure stop marker exists */
1132         for (i = 0; i < FBTFT_MAX_INIT_SEQUENCE; i++)
1133                 if (par->init_sequence[i] == -3)
1134                         break;
1135         if (i == FBTFT_MAX_INIT_SEQUENCE) {
1136                 dev_err(par->info->device,
1137                         "missing stop marker at end of init sequence\n");
1138                 return -EINVAL;
1139         }
1140
1141         par->fbtftops.reset(par);
1142         if (par->gpio.cs != -1)
1143                 gpio_set_value(par->gpio.cs, 0);  /* Activate chip */
1144
1145         i = 0;
1146         while (i < FBTFT_MAX_INIT_SEQUENCE) {
1147                 if (par->init_sequence[i] == -3) {
1148                         /* done */
1149                         return 0;
1150                 }
1151                 if (par->init_sequence[i] >= 0) {
1152                         dev_err(par->info->device,
1153                                 "missing delimiter at position %d\n", i);
1154                         return -EINVAL;
1155                 }
1156                 if (par->init_sequence[i + 1] < 0) {
1157                         dev_err(par->info->device,
1158                                 "missing value after delimiter %d at position %d\n",
1159                                 par->init_sequence[i], i);
1160                         return -EINVAL;
1161                 }
1162                 switch (par->init_sequence[i]) {
1163                 case -1:
1164                         i++;
1165                         /* make debug message */
1166                         strcpy(msg, "");
1167                         j = i + 1;
1168                         while (par->init_sequence[j] >= 0) {
1169                                 sprintf(str, "0x%02X ", par->init_sequence[j]);
1170                                 strcat(msg, str);
1171                                 j++;
1172                         }
1173                         fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
1174                                 "init: write(0x%02X) %s\n",
1175                                 par->init_sequence[i], msg);
1176
1177                         /* Write */
1178                         j = 0;
1179                         while (par->init_sequence[i] >= 0) {
1180                                 if (j > 63) {
1181                                         dev_err(par->info->device,
1182                                         "%s: Maximum register values exceeded\n",
1183                                         __func__);
1184                                         return -EINVAL;
1185                                 }
1186                                 buf[j++] = par->init_sequence[i++];
1187                         }
1188                         par->fbtftops.write_register(par, j,
1189                                 buf[0], buf[1], buf[2], buf[3],
1190                                 buf[4], buf[5], buf[6], buf[7],
1191                                 buf[8], buf[9], buf[10], buf[11],
1192                                 buf[12], buf[13], buf[14], buf[15],
1193                                 buf[16], buf[17], buf[18], buf[19],
1194                                 buf[20], buf[21], buf[22], buf[23],
1195                                 buf[24], buf[25], buf[26], buf[27],
1196                                 buf[28], buf[29], buf[30], buf[31],
1197                                 buf[32], buf[33], buf[34], buf[35],
1198                                 buf[36], buf[37], buf[38], buf[39],
1199                                 buf[40], buf[41], buf[42], buf[43],
1200                                 buf[44], buf[45], buf[46], buf[47],
1201                                 buf[48], buf[49], buf[50], buf[51],
1202                                 buf[52], buf[53], buf[54], buf[55],
1203                                 buf[56], buf[57], buf[58], buf[59],
1204                                 buf[60], buf[61], buf[62], buf[63]);
1205                         break;
1206                 case -2:
1207                         i++;
1208                         fbtft_par_dbg(DEBUG_INIT_DISPLAY, par,
1209                                 "init: mdelay(%d)\n", par->init_sequence[i]);
1210                         mdelay(par->init_sequence[i++]);
1211                         break;
1212                 default:
1213                         dev_err(par->info->device,
1214                                 "unknown delimiter %d at position %d\n",
1215                                 par->init_sequence[i], i);
1216                         return -EINVAL;
1217                 }
1218         }
1219
1220         dev_err(par->info->device,
1221                 "%s: something is wrong. Shouldn't get here.\n", __func__);
1222         return -EINVAL;
1223 }
1224 EXPORT_SYMBOL(fbtft_init_display);
1225
1226 /**
1227  * fbtft_verify_gpios() - Generic verify_gpios() function
1228  * @par: Driver data
1229  *
1230  * Uses @spi, @pdev and @buswidth to determine which GPIOs is needed
1231  *
1232  * Return: 0 if successful, negative if error
1233  */
1234 static int fbtft_verify_gpios(struct fbtft_par *par)
1235 {
1236         struct fbtft_platform_data *pdata = par->pdata;
1237         int i;
1238
1239         fbtft_par_dbg(DEBUG_VERIFY_GPIOS, par, "%s()\n", __func__);
1240
1241         if (pdata->display.buswidth != 9 && par->startbyte == 0 &&
1242                                                         par->gpio.dc < 0) {
1243                 dev_err(par->info->device,
1244                         "Missing info about 'dc' gpio. Aborting.\n");
1245                 return -EINVAL;
1246         }
1247
1248         if (!par->pdev)
1249                 return 0;
1250
1251         if (par->gpio.wr < 0) {
1252                 dev_err(par->info->device, "Missing 'wr' gpio. Aborting.\n");
1253                 return -EINVAL;
1254         }
1255         for (i = 0; i < pdata->display.buswidth; i++) {
1256                 if (par->gpio.db[i] < 0) {
1257                         dev_err(par->info->device,
1258                                 "Missing 'db%02d' gpio. Aborting.\n", i);
1259                         return -EINVAL;
1260                 }
1261         }
1262
1263         return 0;
1264 }
1265
1266 #ifdef CONFIG_OF
1267 /* returns 0 if the property is not present */
1268 static u32 fbtft_of_value(struct device_node *node, const char *propname)
1269 {
1270         int ret;
1271         u32 val = 0;
1272
1273         ret = of_property_read_u32(node, propname, &val);
1274         if (ret == 0)
1275                 pr_info("%s: %s = %u\n", __func__, propname, val);
1276
1277         return val;
1278 }
1279
1280 static struct fbtft_platform_data *fbtft_probe_dt(struct device *dev)
1281 {
1282         struct device_node *node = dev->of_node;
1283         struct fbtft_platform_data *pdata;
1284
1285         if (!node) {
1286                 dev_err(dev, "Missing platform data or DT\n");
1287                 return ERR_PTR(-EINVAL);
1288         }
1289
1290         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
1291         if (!pdata)
1292                 return ERR_PTR(-ENOMEM);
1293
1294         pdata->display.width = fbtft_of_value(node, "width");
1295         pdata->display.height = fbtft_of_value(node, "height");
1296         pdata->display.regwidth = fbtft_of_value(node, "regwidth");
1297         pdata->display.buswidth = fbtft_of_value(node, "buswidth");
1298         pdata->display.backlight = fbtft_of_value(node, "backlight");
1299         pdata->display.bpp = fbtft_of_value(node, "bpp");
1300         pdata->display.debug = fbtft_of_value(node, "debug");
1301         pdata->rotate = fbtft_of_value(node, "rotate");
1302         pdata->bgr = of_property_read_bool(node, "bgr");
1303         pdata->fps = fbtft_of_value(node, "fps");
1304         pdata->txbuflen = fbtft_of_value(node, "txbuflen");
1305         pdata->startbyte = fbtft_of_value(node, "startbyte");
1306         of_property_read_string(node, "gamma", (const char **)&pdata->gamma);
1307
1308         if (of_find_property(node, "led-gpios", NULL))
1309                 pdata->display.backlight = 1;
1310         if (of_find_property(node, "init", NULL))
1311                 pdata->display.fbtftops.init_display = fbtft_init_display_dt;
1312         pdata->display.fbtftops.request_gpios = fbtft_request_gpios_dt;
1313
1314         return pdata;
1315 }
1316 #else
1317 static struct fbtft_platform_data *fbtft_probe_dt(struct device *dev)
1318 {
1319         dev_err(dev, "Missing platform data\n");
1320         return ERR_PTR(-EINVAL);
1321 }
1322 #endif
1323
1324 /**
1325  * fbtft_probe_common() - Generic device probe() helper function
1326  * @display: Display properties
1327  * @sdev: SPI device
1328  * @pdev: Platform device
1329  *
1330  * Allocates, initializes and registers a framebuffer
1331  *
1332  * Either @sdev or @pdev should be NULL
1333  *
1334  * Return: 0 if successful, negative if error
1335  */
1336 int fbtft_probe_common(struct fbtft_display *display,
1337                         struct spi_device *sdev, struct platform_device *pdev)
1338 {
1339         struct device *dev;
1340         struct fb_info *info;
1341         struct fbtft_par *par;
1342         struct fbtft_platform_data *pdata;
1343         int ret;
1344
1345         if (sdev)
1346                 dev = &sdev->dev;
1347         else
1348                 dev = &pdev->dev;
1349
1350         if (unlikely(display->debug & DEBUG_DRIVER_INIT_FUNCTIONS))
1351                 dev_info(dev, "%s()\n", __func__);
1352
1353         pdata = dev->platform_data;
1354         if (!pdata) {
1355                 pdata = fbtft_probe_dt(dev);
1356                 if (IS_ERR(pdata))
1357                         return PTR_ERR(pdata);
1358         }
1359
1360         info = fbtft_framebuffer_alloc(display, dev, pdata);
1361         if (!info)
1362                 return -ENOMEM;
1363
1364         par = info->par;
1365         par->spi = sdev;
1366         par->pdev = pdev;
1367
1368         if (display->buswidth == 0) {
1369                 dev_err(dev, "buswidth is not set\n");
1370                 return -EINVAL;
1371         }
1372
1373         /* write register functions */
1374         if (display->regwidth == 8 && display->buswidth == 8) {
1375                 par->fbtftops.write_register = fbtft_write_reg8_bus8;
1376         } else
1377         if (display->regwidth == 8 && display->buswidth == 9 && par->spi) {
1378                 par->fbtftops.write_register = fbtft_write_reg8_bus9;
1379         } else if (display->regwidth == 16 && display->buswidth == 8) {
1380                 par->fbtftops.write_register = fbtft_write_reg16_bus8;
1381         } else if (display->regwidth == 16 && display->buswidth == 16) {
1382                 par->fbtftops.write_register = fbtft_write_reg16_bus16;
1383         } else {
1384                 dev_warn(dev,
1385                         "no default functions for regwidth=%d and buswidth=%d\n",
1386                         display->regwidth, display->buswidth);
1387         }
1388
1389         /* write_vmem() functions */
1390         if (display->buswidth == 8)
1391                 par->fbtftops.write_vmem = fbtft_write_vmem16_bus8;
1392         else if (display->buswidth == 9)
1393                 par->fbtftops.write_vmem = fbtft_write_vmem16_bus9;
1394         else if (display->buswidth == 16)
1395                 par->fbtftops.write_vmem = fbtft_write_vmem16_bus16;
1396
1397         /* GPIO write() functions */
1398         if (par->pdev) {
1399                 if (display->buswidth == 8)
1400                         par->fbtftops.write = fbtft_write_gpio8_wr;
1401                 else if (display->buswidth == 16)
1402                         par->fbtftops.write = fbtft_write_gpio16_wr;
1403         }
1404
1405         /* 9-bit SPI setup */
1406         if (par->spi && display->buswidth == 9) {
1407                 if (par->spi->master->bits_per_word_mask & SPI_BPW_MASK(9)) {
1408                         par->spi->bits_per_word = 9;
1409                 } else {
1410                         dev_warn(&par->spi->dev,
1411                                 "9-bit SPI not available, emulating using 8-bit.\n");
1412                         /* allocate buffer with room for dc bits */
1413                         par->extra = devm_kzalloc(par->info->device,
1414                                 par->txbuf.len + (par->txbuf.len / 8) + 8,
1415                                 GFP_KERNEL);
1416                         if (!par->extra) {
1417                                 ret = -ENOMEM;
1418                                 goto out_release;
1419                         }
1420                         par->fbtftops.write = fbtft_write_spi_emulate_9;
1421                 }
1422         }
1423
1424         if (!par->fbtftops.verify_gpios)
1425                 par->fbtftops.verify_gpios = fbtft_verify_gpios;
1426
1427         /* make sure we still use the driver provided functions */
1428         fbtft_merge_fbtftops(&par->fbtftops, &display->fbtftops);
1429
1430         /* use init_sequence if provided */
1431         if (par->init_sequence)
1432                 par->fbtftops.init_display = fbtft_init_display;
1433
1434         /* use platform_data provided functions above all */
1435         fbtft_merge_fbtftops(&par->fbtftops, &pdata->display.fbtftops);
1436
1437         ret = fbtft_register_framebuffer(info);
1438         if (ret < 0)
1439                 goto out_release;
1440
1441         return 0;
1442
1443 out_release:
1444         fbtft_framebuffer_release(info);
1445
1446         return ret;
1447 }
1448 EXPORT_SYMBOL(fbtft_probe_common);
1449
1450 /**
1451  * fbtft_remove_common() - Generic device remove() helper function
1452  * @dev: Device
1453  * @info: Framebuffer
1454  *
1455  * Unregisters and releases the framebuffer
1456  *
1457  * Return: 0 if successful, negative if error
1458  */
1459 int fbtft_remove_common(struct device *dev, struct fb_info *info)
1460 {
1461         struct fbtft_par *par;
1462
1463         if (!info)
1464                 return -EINVAL;
1465         par = info->par;
1466         if (par)
1467                 fbtft_par_dbg(DEBUG_DRIVER_INIT_FUNCTIONS, par,
1468                         "%s()\n", __func__);
1469         fbtft_unregister_framebuffer(info);
1470         fbtft_framebuffer_release(info);
1471
1472         return 0;
1473 }
1474 EXPORT_SYMBOL(fbtft_remove_common);
1475
1476 MODULE_LICENSE("GPL");