drivers/mtd/spi/sandbox.c

   1 /*
   2  * Simulate a SPI flash
   3  *
   4  * Copyright (c) 2011-2013 The Chromium OS Authors.
   5  * See file CREDITS for list of people who contributed to this
   6  * project.
   7  *
   8  * Licensed under the GPL-2 or later.
   9  */
  10
  11 #include <common.h>
  12 #include <dm.h>
  13 #include <malloc.h>
  14 #include <spi.h>
  15 #include <os.h>
  16
  17 #include <spi_flash.h>
  18 #include "sf_internal.h"
  19
  20 #include <asm/getopt.h>
  21 #include <asm/spi.h>
  22 #include <asm/state.h>
  23 #include <dm/device-internal.h>
  24 #include <dm/lists.h>
  25 #include <dm/uclass-internal.h>
  26
  27 DECLARE_GLOBAL_DATA_PTR;
  28
  29 /*
  30  * The different states that our SPI flash transitions between.
  31  * We need to keep track of this across multiple xfer calls since
  32  * the SPI bus could possibly call down into us multiple times.
  33  */
  34 enum sandbox_sf_state {
  35         SF_CMD,   /* default state -- we're awaiting a command */
  36         SF_ID,    /* read the flash's (jedec) ID code */
  37         SF_ADDR,  /* processing the offset in the flash to read/etc... */
  38         SF_READ,  /* reading data from the flash */
  39         SF_WRITE, /* writing data to the flash, i.e. page programming */
  40         SF_ERASE, /* erase the flash */
  41         SF_READ_STATUS, /* read the flash's status register */
  42         SF_READ_STATUS1, /* read the flash's status register upper 8 bits*/
  43         SF_WRITE_STATUS, /* write the flash's status register */
  44 };
  45
  46 static const char *sandbox_sf_state_name(enum sandbox_sf_state state)
  47 {
  48         static const char * const states[] = {
  49                 "CMD", "ID", "ADDR", "READ", "WRITE", "ERASE", "READ_STATUS",
  50                 "READ_STATUS1", "WRITE_STATUS",
  51         };
  52         return states[state];
  53 }
  54
  55 /* Bits for the status register */
  56 #define STAT_WIP        (1 << 0)
  57 #define STAT_WEL        (1 << 1)
  58
  59 /* Assume all SPI flashes have 3 byte addresses since they do atm */
  60 #define SF_ADDR_LEN     3
  61
  62 #define IDCODE_LEN 3
  63
  64 /* Used to quickly bulk erase backing store */
  65 static u8 sandbox_sf_0xff[0x1000];
  66
  67 /* Internal state data for each SPI flash */
  68 struct sandbox_spi_flash {
  69         unsigned int cs;        /* Chip select we are attached to */
  70         /*
  71          * As we receive data over the SPI bus, our flash transitions
  72          * between states.  For example, we start off in the SF_CMD
  73          * state where the first byte tells us what operation to perform
  74          * (such as read or write the flash).  But the operation itself
  75          * can go through a few states such as first reading in the
  76          * offset in the flash to perform the requested operation.
  77          * Thus "state" stores the exact state that our machine is in
  78          * while "cmd" stores the overall command we're processing.
  79          */
  80         enum sandbox_sf_state state;
  81         uint cmd;
  82         /* Erase size of current erase command */
  83         uint erase_size;
  84         /* Current position in the flash; used when reading/writing/etc... */
  85         uint off;
  86         /* How many address bytes we've consumed */
  87         uint addr_bytes, pad_addr_bytes;
  88         /* The current flash status (see STAT_XXX defines above) */
  89         u16 status;
  90         /* Data describing the flash we're emulating */
  91         const struct spi_flash_params *data;
  92         /* The file on disk to serv up data from */
  93         int fd;
  94 };
  95
  96 struct sandbox_spi_flash_plat_data {
  97         const char *filename;
  98         const char *device_name;
  99         int bus;
 100         int cs;
 101 };
 102
 103 /**
 104  * This is a very strange probe function. If it has platform data (which may
 105  * have come from the device tree) then this function gets the filename and
 106  * device type from there. Failing that it looks at the command line
 107  * parameter.
 108  */
 109 static int sandbox_sf_probe(struct udevice *dev)
 110 {
 111         /* spec = idcode:file */
 112         struct sandbox_spi_flash *sbsf = dev_get_priv(dev);
 113         const char *file;
 114         size_t len, idname_len;
 115         const struct spi_flash_params *data;
 116         struct sandbox_spi_flash_plat_data *pdata = dev_get_platdata(dev);
 117         struct sandbox_state *state = state_get_current();
 118         struct udevice *bus = dev->parent;
 119         const char *spec = NULL;
 120         int ret = 0;
 121         int cs = -1;
 122         int i;
 123
 124         debug("%s: bus %d, looking for emul=%p: ", __func__, bus->seq, dev);
 125         if (bus->seq >= 0 && bus->seq < CONFIG_SANDBOX_SPI_MAX_BUS) {
 126                 for (i = 0; i < CONFIG_SANDBOX_SPI_MAX_CS; i++) {
 127                         if (state->spi[bus->seq][i].emul == dev)
 128                                 cs = i;
 129                 }
 130         }
 131         if (cs == -1) {
 132                 printf("Error: Unknown chip select for device '%s'",
 133                        dev->name);
 134                 return -EINVAL;
 135         }
 136         debug("found at cs %d\n", cs);
 137
 138         if (!pdata->filename) {
 139                 struct sandbox_state *state = state_get_current();
 140
 141                 assert(bus->seq != -1);
 142                 if (bus->seq < CONFIG_SANDBOX_SPI_MAX_BUS)
 143                         spec = state->spi[bus->seq][cs].spec;
 144                 if (!spec) {
 145                         ret = -ENOENT;
 146                         goto error;
 147                 }
 148
 149                 file = strchr(spec, ':');
 150                 if (!file) {
 151                         printf("sandbox_sf: unable to parse file\n");
 152                         ret = -EINVAL;
 153                         goto error;
 154                 }
 155                 idname_len = file - spec;
 156                 pdata->filename = file + 1;
 157                 pdata->device_name = spec;
 158                 ++file;
 159         } else {
 160                 spec = strchr(pdata->device_name, ',');
 161                 if (spec)
 162                         spec++;
 163                 else
 164                         spec = pdata->device_name;
 165                 idname_len = strlen(spec);
 166         }
 167         debug("%s: device='%s'\n", __func__, spec);
 168
 169         for (data = spi_flash_params_table; data->name; data++) {
 170                 len = strlen(data->name);
 171                 if (idname_len != len)
 172                         continue;
 173                 if (!strncasecmp(spec, data->name, len))
 174                         break;
 175         }
 176         if (!data->name) {
 177                 printf("sandbox_sf: unknown flash '%*s'\n", (int)idname_len,
 178                        spec);
 179                 ret = -EINVAL;
 180                 goto error;
 181         }
 182
 183         if (sandbox_sf_0xff[0] == 0x00)
 184                 memset(sandbox_sf_0xff, 0xff, sizeof(sandbox_sf_0xff));
 185
 186         sbsf->fd = os_open(pdata->filename, 02);
 187         if (sbsf->fd == -1) {
 188                 free(sbsf);
 189                 printf("sandbox_sf: unable to open file '%s'\n",
 190                        pdata->filename);
 191                 ret = -EIO;
 192                 goto error;
 193         }
 194
 195         sbsf->data = data;
 196         sbsf->cs = cs;
 197
 198         return 0;
 199
 200  error:
 201         debug("%s: Got error %d\n", __func__, ret);
 202         return ret;
 203 }
 204
 205 static int sandbox_sf_remove(struct udevice *dev)
 206 {
 207         struct sandbox_spi_flash *sbsf = dev_get_priv(dev);
 208
 209         os_close(sbsf->fd);
 210
 211         return 0;
 212 }
 213
 214 static void sandbox_sf_cs_activate(struct udevice *dev)
 215 {
 216         struct sandbox_spi_flash *sbsf = dev_get_priv(dev);
 217
 218         debug("sandbox_sf: CS activated; state is fresh!\n");
 219
 220         /* CS is asserted, so reset state */
 221         sbsf->off = 0;
 222         sbsf->addr_bytes = 0;
 223         sbsf->pad_addr_bytes = 0;
 224         sbsf->state = SF_CMD;
 225         sbsf->cmd = SF_CMD;
 226 }
 227
 228 static void sandbox_sf_cs_deactivate(struct udevice *dev)
 229 {
 230         debug("sandbox_sf: CS deactivated; cmd done processing!\n");
 231 }
 232
 233 /*
 234  * There are times when the data lines are allowed to tristate.  What
 235  * is actually sensed on the line depends on the hardware.  It could
 236  * always be 0xFF/0x00 (if there are pull ups/downs), or things could
 237  * float and so we'd get garbage back.  This func encapsulates that
 238  * scenario so we can worry about the details here.
 239  */
 240 static void sandbox_spi_tristate(u8 *buf, uint len)
 241 {
 242         /* XXX: make this into a user config option ? */
 243         memset(buf, 0xff, len);
 244 }
 245
 246 /* Figure out what command this stream is telling us to do */
 247 static int sandbox_sf_process_cmd(struct sandbox_spi_flash *sbsf, const u8 *rx,
 248                                   u8 *tx)
 249 {
 250         enum sandbox_sf_state oldstate = sbsf->state;
 251
 252         /* We need to output a byte for the cmd byte we just ate */
 253         if (tx)
 254                 sandbox_spi_tristate(tx, 1);
 255
 256         sbsf->cmd = rx[0];
 257         switch (sbsf->cmd) {
 258         case CMD_READ_ID:
 259                 sbsf->state = SF_ID;
 260                 sbsf->cmd = SF_ID;
 261                 break;
 262         case CMD_READ_ARRAY_FAST:
 263                 sbsf->pad_addr_bytes = 1;
 264         case CMD_READ_ARRAY_SLOW:
 265         case CMD_PAGE_PROGRAM:
 266                 sbsf->state = SF_ADDR;
 267                 break;
 268         case CMD_WRITE_DISABLE:
 269                 debug(" write disabled\n");
 270                 sbsf->status &= ~STAT_WEL;
 271                 break;
 272         case CMD_READ_STATUS:
 273                 sbsf->state = SF_READ_STATUS;
 274                 break;
 275         case CMD_READ_STATUS1:
 276                 sbsf->state = SF_READ_STATUS1;
 277                 break;
 278         case CMD_WRITE_ENABLE:
 279                 debug(" write enabled\n");
 280                 sbsf->status |= STAT_WEL;
 281                 break;
 282         case CMD_WRITE_STATUS:
 283                 sbsf->state = SF_WRITE_STATUS;
 284                 break;
 285         default: {
 286                 int flags = sbsf->data->flags;
 287
 288                 /* we only support erase here */
 289                 if (sbsf->cmd == CMD_ERASE_CHIP) {
 290                         sbsf->erase_size = sbsf->data->sector_size *
 291                                 sbsf->data->nr_sectors;
 292                 } else if (sbsf->cmd == CMD_ERASE_4K && (flags & SECT_4K)) {
 293                         sbsf->erase_size = 4 << 10;
 294                 } else if (sbsf->cmd == CMD_ERASE_32K && (flags & SECT_32K)) {
 295                         sbsf->erase_size = 32 << 10;
 296                 } else if (sbsf->cmd == CMD_ERASE_64K &&
 297                            !(flags & (SECT_4K | SECT_32K))) {
 298                         sbsf->erase_size = 64 << 10;
 299                 } else {
 300                         debug(" cmd unknown: %#x\n", sbsf->cmd);
 301                         return -EIO;
 302                 }
 303                 sbsf->state = SF_ADDR;
 304                 break;
 305         }
 306         }
 307
 308         if (oldstate != sbsf->state)
 309                 debug(" cmd: transition to %s state\n",
 310                       sandbox_sf_state_name(sbsf->state));
 311
 312         return 0;
 313 }
 314
 315 int sandbox_erase_part(struct sandbox_spi_flash *sbsf, int size)
 316 {
 317         int todo;
 318         int ret;
 319
 320         while (size > 0) {
 321                 todo = min(size, (int)sizeof(sandbox_sf_0xff));
 322                 ret = os_write(sbsf->fd, sandbox_sf_0xff, todo);
 323                 if (ret != todo)
 324                         return ret;
 325                 size -= todo;
 326         }
 327
 328         return 0;
 329 }
 330
 331 static int sandbox_sf_xfer(struct udevice *dev, unsigned int bitlen,
 332                            const void *rxp, void *txp, unsigned long flags)
 333 {
 334         struct sandbox_spi_flash *sbsf = dev_get_priv(dev);
 335         const uint8_t *rx = rxp;
 336         uint8_t *tx = txp;
 337         uint cnt, pos = 0;
 338         int bytes = bitlen / 8;
 339         int ret;
 340
 341         debug("sandbox_sf: state:%x(%s) bytes:%u\n", sbsf->state,
 342               sandbox_sf_state_name(sbsf->state), bytes);
 343
 344         if ((flags & SPI_XFER_BEGIN))
 345                 sandbox_sf_cs_activate(dev);
 346
 347         if (sbsf->state == SF_CMD) {
 348                 /* Figure out the initial state */
 349                 ret = sandbox_sf_process_cmd(sbsf, rx, tx);
 350                 if (ret)
 351                         return ret;
 352                 ++pos;
 353         }
 354
 355         /* Process the remaining data */
 356         while (pos < bytes) {
 357                 switch (sbsf->state) {
 358                 case SF_ID: {
 359                         u8 id;
 360
 361                         debug(" id: off:%u tx:", sbsf->off);
 362                         if (sbsf->off < IDCODE_LEN) {
 363                                 /* Extract correct byte from ID 0x00aabbcc */
 364                                 id = sbsf->data->jedec >>
 365                                         (8 * (IDCODE_LEN - 1 - sbsf->off));
 366                         } else {
 367                                 id = 0;
 368                         }
 369                         debug("%d %02x\n", sbsf->off, id);
 370                         tx[pos++] = id;
 371                         ++sbsf->off;
 372                         break;
 373                 }
 374                 case SF_ADDR:
 375                         debug(" addr: bytes:%u rx:%02x ", sbsf->addr_bytes,
 376                               rx[pos]);
 377
 378                         if (sbsf->addr_bytes++ < SF_ADDR_LEN)
 379                                 sbsf->off = (sbsf->off << 8) | rx[pos];
 380                         debug("addr:%06x\n", sbsf->off);
 381
 382                         if (tx)
 383                                 sandbox_spi_tristate(&tx[pos], 1);
 384                         pos++;
 385
 386                         /* See if we're done processing */
 387                         if (sbsf->addr_bytes <
 388                                         SF_ADDR_LEN + sbsf->pad_addr_bytes)
 389                                 break;
 390
 391                         /* Next state! */
 392                         if (os_lseek(sbsf->fd, sbsf->off, OS_SEEK_SET) < 0) {
 393                                 puts("sandbox_sf: os_lseek() failed");
 394                                 return -EIO;
 395                         }
 396                         switch (sbsf->cmd) {
 397                         case CMD_READ_ARRAY_FAST:
 398                         case CMD_READ_ARRAY_SLOW:
 399                                 sbsf->state = SF_READ;
 400                                 break;
 401                         case CMD_PAGE_PROGRAM:
 402                                 sbsf->state = SF_WRITE;
 403                                 break;
 404                         default:
 405                                 /* assume erase state ... */
 406                                 sbsf->state = SF_ERASE;
 407                                 goto case_sf_erase;
 408                         }
 409                         debug(" cmd: transition to %s state\n",
 410                               sandbox_sf_state_name(sbsf->state));
 411                         break;
 412                 case SF_READ:
 413                         /*
 414                          * XXX: need to handle exotic behavior:
 415                          *      - reading past end of device
 416                          */
 417
 418                         cnt = bytes - pos;
 419                         debug(" tx: read(%u)\n", cnt);
 420                         assert(tx);
 421                         ret = os_read(sbsf->fd, tx + pos, cnt);
 422                         if (ret < 0) {
 423                                 puts("sandbox_sf: os_read() failed\n");
 424                                 return -EIO;
 425                         }
 426                         pos += ret;
 427                         break;
 428                 case SF_READ_STATUS:
 429                         debug(" read status: %#x\n", sbsf->status);
 430                         cnt = bytes - pos;
 431                         memset(tx + pos, sbsf->status, cnt);
 432                         pos += cnt;
 433                         break;
 434                 case SF_READ_STATUS1:
 435                         debug(" read status: %#x\n", sbsf->status);
 436                         cnt = bytes - pos;
 437                         memset(tx + pos, sbsf->status >> 8, cnt);
 438                         pos += cnt;
 439                         break;
 440                 case SF_WRITE_STATUS:
 441                         debug(" write status: %#x (ignored)\n", rx[pos]);
 442                         pos = bytes;
 443                         break;
 444                 case SF_WRITE:
 445                         /*
 446                          * XXX: need to handle exotic behavior:
 447                          *      - unaligned addresses
 448                          *      - more than a page (256) worth of data
 449                          *      - reading past end of device
 450                          */
 451                         if (!(sbsf->status & STAT_WEL)) {
 452                                 puts("sandbox_sf: write enable not set before write\n");
 453                                 goto done;
 454                         }
 455
 456                         cnt = bytes - pos;
 457                         debug(" rx: write(%u)\n", cnt);
 458                         if (tx)
 459                                 sandbox_spi_tristate(&tx[pos], cnt);
 460                         ret = os_write(sbsf->fd, rx + pos, cnt);
 461                         if (ret < 0) {
 462                                 puts("sandbox_spi: os_write() failed\n");
 463                                 return -EIO;
 464                         }
 465                         pos += ret;
 466                         sbsf->status &= ~STAT_WEL;
 467                         break;
 468                 case SF_ERASE:
 469  case_sf_erase: {
 470                         if (!(sbsf->status & STAT_WEL)) {
 471                                 puts("sandbox_sf: write enable not set before erase\n");
 472                                 goto done;
 473                         }
 474
 475                         /* verify address is aligned */
 476                         if (sbsf->off & (sbsf->erase_size - 1)) {
 477                                 debug(" sector erase: cmd:%#x needs align:%#x, but we got %#x\n",
 478                                       sbsf->cmd, sbsf->erase_size,
 479                                       sbsf->off);
 480                                 sbsf->status &= ~STAT_WEL;
 481                                 goto done;
 482                         }
 483
 484                         debug(" sector erase addr: %u, size: %u\n", sbsf->off,
 485                               sbsf->erase_size);
 486
 487                         cnt = bytes - pos;
 488                         if (tx)
 489                                 sandbox_spi_tristate(&tx[pos], cnt);
 490                         pos += cnt;
 491
 492                         /*
 493                          * TODO(vapier@gentoo.org): latch WIP in status, and
 494                          * delay before clearing it ?
 495                          */
 496                         ret = sandbox_erase_part(sbsf, sbsf->erase_size);
 497                         sbsf->status &= ~STAT_WEL;
 498                         if (ret) {
 499                                 debug("sandbox_sf: Erase failed\n");
 500                                 goto done;
 501                         }
 502                         goto done;
 503                 }
 504                 default:
 505                         debug(" ??? no idea what to do ???\n");
 506                         goto done;
 507                 }
 508         }
 509
 510  done:
 511         if (flags & SPI_XFER_END)
 512                 sandbox_sf_cs_deactivate(dev);
 513         return pos == bytes ? 0 : -EIO;
 514 }
 515
 516 int sandbox_sf_ofdata_to_platdata(struct udevice *dev)
 517 {
 518         struct sandbox_spi_flash_plat_data *pdata = dev_get_platdata(dev);
 519         const void *blob = gd->fdt_blob;
 520         int node = dev->of_offset;
 521
 522         pdata->filename = fdt_getprop(blob, node, "sandbox,filename", NULL);
 523         pdata->device_name = fdt_getprop(blob, node, "compatible", NULL);
 524         if (!pdata->filename || !pdata->device_name) {
 525                 debug("%s: Missing properties, filename=%s, device_name=%s\n",
 526                       __func__, pdata->filename, pdata->device_name);
 527                 return -EINVAL;
 528         }
 529
 530         return 0;
 531 }
 532
 533 static const struct dm_spi_emul_ops sandbox_sf_emul_ops = {
 534         .xfer          = sandbox_sf_xfer,
 535 };
 536
 537 #ifdef CONFIG_SPI_FLASH
 538 static int sandbox_cmdline_cb_spi_sf(struct sandbox_state *state,
 539                                      const char *arg)
 540 {
 541         unsigned long bus, cs;
 542         const char *spec = sandbox_spi_parse_spec(arg, &bus, &cs);
 543
 544         if (!spec)
 545                 return 1;
 546
 547         /*
 548          * It is safe to not make a copy of 'spec' because it comes from the
 549          * command line.
 550          *
 551          * TODO(sjg@chromium.org): It would be nice if we could parse the
 552          * spec here, but the problem is that no U-Boot init has been done
 553          * yet. Perhaps we can figure something out.
 554          */
 555         state->spi[bus][cs].spec = spec;
 556         return 0;
 557 }
 558 SANDBOX_CMDLINE_OPT(spi_sf, 1, "connect a SPI flash: <bus>:<cs>:<id>:<file>");
 559
 560 int sandbox_sf_bind_emul(struct sandbox_state *state, int busnum, int cs,
 561                          struct udevice *bus, int of_offset, const char *spec)
 562 {
 563         struct udevice *emul;
 564         char name[20], *str;
 565         struct driver *drv;
 566         int ret;
 567
 568         /* now the emulator */
 569         strncpy(name, spec, sizeof(name) - 6);
 570         name[sizeof(name) - 6] = '\0';
 571         strcat(name, "-emul");
 572         str = strdup(name);
 573         if (!str)
 574                 return -ENOMEM;
 575         drv = lists_driver_lookup_name("sandbox_sf_emul");
 576         if (!drv) {
 577                 puts("Cannot find sandbox_sf_emul driver\n");
 578                 return -ENOENT;
 579         }
 580         ret = device_bind(bus, drv, str, NULL, of_offset, &emul);
 581         if (ret) {
 582                 printf("Cannot create emul device for spec '%s' (err=%d)\n",
 583                        spec, ret);
 584                 return ret;
 585         }
 586         state->spi[busnum][cs].emul = emul;
 587
 588         return 0;
 589 }
 590
 591 void sandbox_sf_unbind_emul(struct sandbox_state *state, int busnum, int cs)
 592 {
 593         struct udevice *dev;
 594
 595         dev = state->spi[busnum][cs].emul;
 596         device_remove(dev);
 597         device_unbind(dev);
 598         state->spi[busnum][cs].emul = NULL;
 599 }
 600
 601 static int sandbox_sf_bind_bus_cs(struct sandbox_state *state, int busnum,
 602                                   int cs, const char *spec)
 603 {
 604         struct udevice *bus, *slave;
 605         int ret;
 606
 607         ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, true, &bus);
 608         if (ret) {
 609                 printf("Invalid bus %d for spec '%s' (err=%d)\n", busnum,
 610                        spec, ret);
 611                 return ret;
 612         }
 613         ret = spi_find_chip_select(bus, cs, &slave);
 614         if (!ret) {
 615                 printf("Chip select %d already exists for spec '%s'\n", cs,
 616                        spec);
 617                 return -EEXIST;
 618         }
 619
 620         ret = device_bind_driver(bus, "spi_flash_std", spec, &slave);
 621         if (ret)
 622                 return ret;
 623
 624         return sandbox_sf_bind_emul(state, busnum, cs, bus, -1, spec);
 625 }
 626
 627 int sandbox_spi_get_emul(struct sandbox_state *state,
 628                          struct udevice *bus, struct udevice *slave,
 629                          struct udevice **emulp)
 630 {
 631         struct sandbox_spi_info *info;
 632         int busnum = bus->seq;
 633         int cs = spi_chip_select(slave);
 634         int ret;
 635
 636         info = &state->spi[busnum][cs];
 637         if (!info->emul) {
 638                 /* Use the same device tree node as the SPI flash device */
 639                 debug("%s: busnum=%u, cs=%u: binding SPI flash emulation: ",
 640                       __func__, busnum, cs);
 641                 ret = sandbox_sf_bind_emul(state, busnum, cs, bus,
 642                                            slave->of_offset, slave->name);
 643                 if (ret) {
 644                         debug("failed (err=%d)\n", ret);
 645                         return ret;
 646                 }
 647                 debug("OK\n");
 648         }
 649         *emulp = info->emul;
 650
 651         return 0;
 652 }
 653
 654 int dm_scan_other(bool pre_reloc_only)
 655 {
 656         struct sandbox_state *state = state_get_current();
 657         int busnum, cs;
 658
 659         if (pre_reloc_only)
 660                 return 0;
 661         for (busnum = 0; busnum < CONFIG_SANDBOX_SPI_MAX_BUS; busnum++) {
 662                 for (cs = 0; cs < CONFIG_SANDBOX_SPI_MAX_CS; cs++) {
 663                         const char *spec = state->spi[busnum][cs].spec;
 664                         int ret;
 665
 666                         if (spec) {
 667                                 ret = sandbox_sf_bind_bus_cs(state, busnum,
 668                                                              cs, spec);
 669                                 if (ret) {
 670                                         debug("%s: Bind failed for bus %d, cs %d\n",
 671                                               __func__, busnum, cs);
 672                                         return ret;
 673                                 }
 674                         }
 675                 }
 676         }
 677
 678         return 0;
 679 }
 680 #endif
 681
 682 static const struct udevice_id sandbox_sf_ids[] = {
 683         { .compatible = "sandbox,spi-flash" },
 684         { }
 685 };
 686
 687 U_BOOT_DRIVER(sandbox_sf_emul) = {
 688         .name           = "sandbox_sf_emul",
 689         .id             = UCLASS_SPI_EMUL,
 690         .of_match       = sandbox_sf_ids,
 691         .ofdata_to_platdata = sandbox_sf_ofdata_to_platdata,
 692         .probe          = sandbox_sf_probe,
 693         .remove         = sandbox_sf_remove,
 694         .priv_auto_alloc_size = sizeof(struct sandbox_spi_flash),
 695         .platdata_auto_alloc_size = sizeof(struct sandbox_spi_flash_plat_data),
 696         .ops            = &sandbox_sf_emul_ops,
 697 };