drivers/spi/spi-fsi.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 // Copyright (C) IBM Corporation 2020
   3
   4 #include <linux/bitfield.h>
   5 #include <linux/bits.h>
   6 #include <linux/fsi.h>
   7 #include <linux/jiffies.h>
   8 #include <linux/kernel.h>
   9 #include <linux/module.h>
  10 #include <linux/of.h>
  11 #include <linux/spi/spi.h>
  12
  13 #define FSI_ENGID_SPI                   0x23
  14 #define FSI_MBOX_ROOT_CTRL_8            0x2860
  15 #define  FSI_MBOX_ROOT_CTRL_8_SPI_MUX    0xf0000000
  16
  17 #define FSI2SPI_DATA0                   0x00
  18 #define FSI2SPI_DATA1                   0x04
  19 #define FSI2SPI_CMD                     0x08
  20 #define  FSI2SPI_CMD_WRITE               BIT(31)
  21 #define FSI2SPI_RESET                   0x18
  22 #define FSI2SPI_STATUS                  0x1c
  23 #define  FSI2SPI_STATUS_ANY_ERROR        BIT(31)
  24 #define FSI2SPI_IRQ                     0x20
  25
  26 #define SPI_FSI_BASE                    0x70000
  27 #define SPI_FSI_INIT_TIMEOUT_MS         1000
  28 #define SPI_FSI_MAX_XFR_SIZE            2048
  29 #define SPI_FSI_MAX_XFR_SIZE_RESTRICTED 8
  30
  31 #define SPI_FSI_ERROR                   0x0
  32 #define SPI_FSI_COUNTER_CFG             0x1
  33 #define  SPI_FSI_COUNTER_CFG_LOOPS(x)    (((u64)(x) & 0xffULL) << 32)
  34 #define  SPI_FSI_COUNTER_CFG_N2_RX       BIT_ULL(8)
  35 #define  SPI_FSI_COUNTER_CFG_N2_TX       BIT_ULL(9)
  36 #define  SPI_FSI_COUNTER_CFG_N2_IMPLICIT BIT_ULL(10)
  37 #define  SPI_FSI_COUNTER_CFG_N2_RELOAD   BIT_ULL(11)
  38 #define SPI_FSI_CFG1                    0x2
  39 #define SPI_FSI_CLOCK_CFG               0x3
  40 #define  SPI_FSI_CLOCK_CFG_MM_ENABLE     BIT_ULL(32)
  41 #define  SPI_FSI_CLOCK_CFG_ECC_DISABLE   (BIT_ULL(35) | BIT_ULL(33))
  42 #define  SPI_FSI_CLOCK_CFG_RESET1        (BIT_ULL(36) | BIT_ULL(38))
  43 #define  SPI_FSI_CLOCK_CFG_RESET2        (BIT_ULL(37) | BIT_ULL(39))
  44 #define  SPI_FSI_CLOCK_CFG_MODE          (BIT_ULL(41) | BIT_ULL(42))
  45 #define  SPI_FSI_CLOCK_CFG_SCK_RECV_DEL  GENMASK_ULL(51, 44)
  46 #define   SPI_FSI_CLOCK_CFG_SCK_NO_DEL    BIT_ULL(51)
  47 #define  SPI_FSI_CLOCK_CFG_SCK_DIV       GENMASK_ULL(63, 52)
  48 #define SPI_FSI_MMAP                    0x4
  49 #define SPI_FSI_DATA_TX                 0x5
  50 #define SPI_FSI_DATA_RX                 0x6
  51 #define SPI_FSI_SEQUENCE                0x7
  52 #define  SPI_FSI_SEQUENCE_STOP           0x00
  53 #define  SPI_FSI_SEQUENCE_SEL_SLAVE(x)   (0x10 | ((x) & 0xf))
  54 #define  SPI_FSI_SEQUENCE_SHIFT_OUT(x)   (0x30 | ((x) & 0xf))
  55 #define  SPI_FSI_SEQUENCE_SHIFT_IN(x)    (0x40 | ((x) & 0xf))
  56 #define  SPI_FSI_SEQUENCE_COPY_DATA_TX   0xc0
  57 #define  SPI_FSI_SEQUENCE_BRANCH(x)      (0xe0 | ((x) & 0xf))
  58 #define SPI_FSI_STATUS                  0x8
  59 #define  SPI_FSI_STATUS_ERROR            \
  60         (GENMASK_ULL(31, 21) | GENMASK_ULL(15, 12))
  61 #define  SPI_FSI_STATUS_SEQ_STATE        GENMASK_ULL(55, 48)
  62 #define   SPI_FSI_STATUS_SEQ_STATE_IDLE   BIT_ULL(48)
  63 #define  SPI_FSI_STATUS_TDR_UNDERRUN     BIT_ULL(57)
  64 #define  SPI_FSI_STATUS_TDR_OVERRUN      BIT_ULL(58)
  65 #define  SPI_FSI_STATUS_TDR_FULL         BIT_ULL(59)
  66 #define  SPI_FSI_STATUS_RDR_UNDERRUN     BIT_ULL(61)
  67 #define  SPI_FSI_STATUS_RDR_OVERRUN      BIT_ULL(62)
  68 #define  SPI_FSI_STATUS_RDR_FULL         BIT_ULL(63)
  69 #define  SPI_FSI_STATUS_ANY_ERROR        \
  70         (SPI_FSI_STATUS_ERROR | \
  71          SPI_FSI_STATUS_TDR_OVERRUN | SPI_FSI_STATUS_RDR_UNDERRUN | \
  72          SPI_FSI_STATUS_RDR_OVERRUN)
  73 #define SPI_FSI_PORT_CTRL               0x9
  74
  75 struct fsi_spi {
  76         struct device *dev;     /* SPI controller device */
  77         struct fsi_device *fsi; /* FSI2SPI CFAM engine device */
  78         u32 base;
  79         size_t max_xfr_size;
  80         bool restricted;
  81 };
  82
  83 struct fsi_spi_sequence {
  84         int bit;
  85         u64 data;
  86 };
  87
  88 static int fsi_spi_check_mux(struct fsi_device *fsi, struct device *dev)
  89 {
  90         int rc;
  91         u32 root_ctrl_8;
  92         __be32 root_ctrl_8_be;
  93
  94         rc = fsi_slave_read(fsi->slave, FSI_MBOX_ROOT_CTRL_8, &root_ctrl_8_be,
  95                             sizeof(root_ctrl_8_be));
  96         if (rc)
  97                 return rc;
  98
  99         root_ctrl_8 = be32_to_cpu(root_ctrl_8_be);
 100         dev_dbg(dev, "Root control register 8: %08x\n", root_ctrl_8);
 101         if ((root_ctrl_8 & FSI_MBOX_ROOT_CTRL_8_SPI_MUX) ==
 102              FSI_MBOX_ROOT_CTRL_8_SPI_MUX)
 103                 return 0;
 104
 105         return -ENOLINK;
 106 }
 107
 108 static int fsi_spi_check_status(struct fsi_spi *ctx)
 109 {
 110         int rc;
 111         u32 sts;
 112         __be32 sts_be;
 113
 114         rc = fsi_device_read(ctx->fsi, FSI2SPI_STATUS, &sts_be,
 115                              sizeof(sts_be));
 116         if (rc)
 117                 return rc;
 118
 119         sts = be32_to_cpu(sts_be);
 120         if (sts & FSI2SPI_STATUS_ANY_ERROR) {
 121                 dev_err(ctx->dev, "Error with FSI2SPI interface: %08x.\n", sts);
 122                 return -EIO;
 123         }
 124
 125         return 0;
 126 }
 127
 128 static int fsi_spi_read_reg(struct fsi_spi *ctx, u32 offset, u64 *value)
 129 {
 130         int rc;
 131         __be32 cmd_be;
 132         __be32 data_be;
 133         u32 cmd = offset + ctx->base;
 134
 135         *value = 0ULL;
 136
 137         if (cmd & FSI2SPI_CMD_WRITE)
 138                 return -EINVAL;
 139
 140         cmd_be = cpu_to_be32(cmd);
 141         rc = fsi_device_write(ctx->fsi, FSI2SPI_CMD, &cmd_be, sizeof(cmd_be));
 142         if (rc)
 143                 return rc;
 144
 145         rc = fsi_spi_check_status(ctx);
 146         if (rc)
 147                 return rc;
 148
 149         rc = fsi_device_read(ctx->fsi, FSI2SPI_DATA0, &data_be,
 150                              sizeof(data_be));
 151         if (rc)
 152                 return rc;
 153
 154         *value |= (u64)be32_to_cpu(data_be) << 32;
 155
 156         rc = fsi_device_read(ctx->fsi, FSI2SPI_DATA1, &data_be,
 157                              sizeof(data_be));
 158         if (rc)
 159                 return rc;
 160
 161         *value |= (u64)be32_to_cpu(data_be);
 162         dev_dbg(ctx->dev, "Read %02x[%016llx].\n", offset, *value);
 163
 164         return 0;
 165 }
 166
 167 static int fsi_spi_write_reg(struct fsi_spi *ctx, u32 offset, u64 value)
 168 {
 169         int rc;
 170         __be32 cmd_be;
 171         __be32 data_be;
 172         u32 cmd = offset + ctx->base;
 173
 174         if (cmd & FSI2SPI_CMD_WRITE)
 175                 return -EINVAL;
 176
 177         dev_dbg(ctx->dev, "Write %02x[%016llx].\n", offset, value);
 178
 179         data_be = cpu_to_be32(upper_32_bits(value));
 180         rc = fsi_device_write(ctx->fsi, FSI2SPI_DATA0, &data_be,
 181                               sizeof(data_be));
 182         if (rc)
 183                 return rc;
 184
 185         data_be = cpu_to_be32(lower_32_bits(value));
 186         rc = fsi_device_write(ctx->fsi, FSI2SPI_DATA1, &data_be,
 187                               sizeof(data_be));
 188         if (rc)
 189                 return rc;
 190
 191         cmd_be = cpu_to_be32(cmd | FSI2SPI_CMD_WRITE);
 192         rc = fsi_device_write(ctx->fsi, FSI2SPI_CMD, &cmd_be, sizeof(cmd_be));
 193         if (rc)
 194                 return rc;
 195
 196         return fsi_spi_check_status(ctx);
 197 }
 198
 199 static int fsi_spi_data_in(u64 in, u8 *rx, int len)
 200 {
 201         int i;
 202         int num_bytes = min(len, 8);
 203
 204         for (i = 0; i < num_bytes; ++i)
 205                 rx[i] = (u8)(in >> (8 * ((num_bytes - 1) - i)));
 206
 207         return num_bytes;
 208 }
 209
 210 static int fsi_spi_data_out(u64 *out, const u8 *tx, int len)
 211 {
 212         int i;
 213         int num_bytes = min(len, 8);
 214         u8 *out_bytes = (u8 *)out;
 215
 216         /* Unused bytes of the tx data should be 0. */
 217         *out = 0ULL;
 218
 219         for (i = 0; i < num_bytes; ++i)
 220                 out_bytes[8 - (i + 1)] = tx[i];
 221
 222         return num_bytes;
 223 }
 224
 225 static int fsi_spi_reset(struct fsi_spi *ctx)
 226 {
 227         int rc;
 228
 229         dev_dbg(ctx->dev, "Resetting SPI controller.\n");
 230
 231         rc = fsi_spi_write_reg(ctx, SPI_FSI_CLOCK_CFG,
 232                                SPI_FSI_CLOCK_CFG_RESET1);
 233         if (rc)
 234                 return rc;
 235
 236         rc = fsi_spi_write_reg(ctx, SPI_FSI_CLOCK_CFG,
 237                                SPI_FSI_CLOCK_CFG_RESET2);
 238         if (rc)
 239                 return rc;
 240
 241         return fsi_spi_write_reg(ctx, SPI_FSI_STATUS, 0ULL);
 242 }
 243
 244 static int fsi_spi_sequence_add(struct fsi_spi_sequence *seq, u8 val)
 245 {
 246         /*
 247          * Add the next byte of instruction to the 8-byte sequence register.
 248          * Then decrement the counter so that the next instruction will go in
 249          * the right place. Return the index of the slot we just filled in the
 250          * sequence register.
 251          */
 252         seq->data |= (u64)val << seq->bit;
 253         seq->bit -= 8;
 254
 255         return ((64 - seq->bit) / 8) - 2;
 256 }
 257
 258 static void fsi_spi_sequence_init(struct fsi_spi_sequence *seq)
 259 {
 260         seq->bit = 56;
 261         seq->data = 0ULL;
 262 }
 263
 264 static int fsi_spi_sequence_transfer(struct fsi_spi *ctx,
 265                                      struct fsi_spi_sequence *seq,
 266                                      struct spi_transfer *transfer)
 267 {
 268         int loops;
 269         int idx;
 270         int rc;
 271         u8 val = 0;
 272         u8 len = min(transfer->len, 8U);
 273         u8 rem = transfer->len % len;
 274
 275         loops = transfer->len / len;
 276
 277         if (transfer->tx_buf) {
 278                 val = SPI_FSI_SEQUENCE_SHIFT_OUT(len);
 279                 idx = fsi_spi_sequence_add(seq, val);
 280
 281                 if (rem)
 282                         rem = SPI_FSI_SEQUENCE_SHIFT_OUT(rem);
 283         } else if (transfer->rx_buf) {
 284                 val = SPI_FSI_SEQUENCE_SHIFT_IN(len);
 285                 idx = fsi_spi_sequence_add(seq, val);
 286
 287                 if (rem)
 288                         rem = SPI_FSI_SEQUENCE_SHIFT_IN(rem);
 289         } else {
 290                 return -EINVAL;
 291         }
 292
 293         if (ctx->restricted && loops > 1) {
 294                 dev_warn(ctx->dev,
 295                          "Transfer too large; no branches permitted.\n");
 296                 return -EINVAL;
 297         }
 298
 299         if (loops > 1) {
 300                 u64 cfg = SPI_FSI_COUNTER_CFG_LOOPS(loops - 1);
 301
 302                 fsi_spi_sequence_add(seq, SPI_FSI_SEQUENCE_BRANCH(idx));
 303
 304                 if (transfer->rx_buf)
 305                         cfg |= SPI_FSI_COUNTER_CFG_N2_RX |
 306                                 SPI_FSI_COUNTER_CFG_N2_TX |
 307                                 SPI_FSI_COUNTER_CFG_N2_IMPLICIT |
 308                                 SPI_FSI_COUNTER_CFG_N2_RELOAD;
 309
 310                 rc = fsi_spi_write_reg(ctx, SPI_FSI_COUNTER_CFG, cfg);
 311                 if (rc)
 312                         return rc;
 313         } else {
 314                 fsi_spi_write_reg(ctx, SPI_FSI_COUNTER_CFG, 0ULL);
 315         }
 316
 317         if (rem)
 318                 fsi_spi_sequence_add(seq, rem);
 319
 320         return 0;
 321 }
 322
 323 static int fsi_spi_transfer_data(struct fsi_spi *ctx,
 324                                  struct spi_transfer *transfer)
 325 {
 326         int rc = 0;
 327         u64 status = 0ULL;
 328         u64 cfg = 0ULL;
 329
 330         if (transfer->tx_buf) {
 331                 int nb;
 332                 int sent = 0;
 333                 u64 out = 0ULL;
 334                 const u8 *tx = transfer->tx_buf;
 335
 336                 while (transfer->len > sent) {
 337                         nb = fsi_spi_data_out(&out, &tx[sent],
 338                                               (int)transfer->len - sent);
 339
 340                         rc = fsi_spi_write_reg(ctx, SPI_FSI_DATA_TX, out);
 341                         if (rc)
 342                                 return rc;
 343
 344                         do {
 345                                 rc = fsi_spi_read_reg(ctx, SPI_FSI_STATUS,
 346                                                       &status);
 347                                 if (rc)
 348                                         return rc;
 349
 350                                 if (status & SPI_FSI_STATUS_ANY_ERROR) {
 351                                         rc = fsi_spi_reset(ctx);
 352                                         if (rc)
 353                                                 return rc;
 354
 355                                         return -EREMOTEIO;
 356                                 }
 357                         } while (status & SPI_FSI_STATUS_TDR_FULL);
 358
 359                         sent += nb;
 360                 }
 361         } else if (transfer->rx_buf) {
 362                 int recv = 0;
 363                 u64 in = 0ULL;
 364                 u8 *rx = transfer->rx_buf;
 365
 366                 rc = fsi_spi_read_reg(ctx, SPI_FSI_COUNTER_CFG, &cfg);
 367                 if (rc)
 368                         return rc;
 369
 370                 if (cfg & SPI_FSI_COUNTER_CFG_N2_IMPLICIT) {
 371                         rc = fsi_spi_write_reg(ctx, SPI_FSI_DATA_TX, 0);
 372                         if (rc)
 373                                 return rc;
 374                 }
 375
 376                 while (transfer->len > recv) {
 377                         do {
 378                                 rc = fsi_spi_read_reg(ctx, SPI_FSI_STATUS,
 379                                                       &status);
 380                                 if (rc)
 381                                         return rc;
 382
 383                                 if (status & SPI_FSI_STATUS_ANY_ERROR) {
 384                                         rc = fsi_spi_reset(ctx);
 385                                         if (rc)
 386                                                 return rc;
 387
 388                                         return -EREMOTEIO;
 389                                 }
 390                         } while (!(status & SPI_FSI_STATUS_RDR_FULL));
 391
 392                         rc = fsi_spi_read_reg(ctx, SPI_FSI_DATA_RX, &in);
 393                         if (rc)
 394                                 return rc;
 395
 396                         recv += fsi_spi_data_in(in, &rx[recv],
 397                                                 (int)transfer->len - recv);
 398                 }
 399         }
 400
 401         return 0;
 402 }
 403
 404 static int fsi_spi_transfer_init(struct fsi_spi *ctx)
 405 {
 406         int rc;
 407         bool reset = false;
 408         unsigned long end;
 409         u64 seq_state;
 410         u64 clock_cfg = 0ULL;
 411         u64 status = 0ULL;
 412         u64 wanted_clock_cfg = SPI_FSI_CLOCK_CFG_ECC_DISABLE |
 413                 SPI_FSI_CLOCK_CFG_SCK_NO_DEL |
 414                 FIELD_PREP(SPI_FSI_CLOCK_CFG_SCK_DIV, 19);
 415
 416         end = jiffies + msecs_to_jiffies(SPI_FSI_INIT_TIMEOUT_MS);
 417         do {
 418                 if (time_after(jiffies, end))
 419                         return -ETIMEDOUT;
 420
 421                 rc = fsi_spi_read_reg(ctx, SPI_FSI_STATUS, &status);
 422                 if (rc)
 423                         return rc;
 424
 425                 seq_state = status & SPI_FSI_STATUS_SEQ_STATE;
 426
 427                 if (status & (SPI_FSI_STATUS_ANY_ERROR |
 428                               SPI_FSI_STATUS_TDR_FULL |
 429                               SPI_FSI_STATUS_RDR_FULL)) {
 430                         if (reset)
 431                                 return -EIO;
 432
 433                         rc = fsi_spi_reset(ctx);
 434                         if (rc)
 435                                 return rc;
 436
 437                         reset = true;
 438                         continue;
 439                 }
 440         } while (seq_state && (seq_state != SPI_FSI_STATUS_SEQ_STATE_IDLE));
 441
 442         rc = fsi_spi_read_reg(ctx, SPI_FSI_CLOCK_CFG, &clock_cfg);
 443         if (rc)
 444                 return rc;
 445
 446         if ((clock_cfg & (SPI_FSI_CLOCK_CFG_MM_ENABLE |
 447                           SPI_FSI_CLOCK_CFG_ECC_DISABLE |
 448                           SPI_FSI_CLOCK_CFG_MODE |
 449                           SPI_FSI_CLOCK_CFG_SCK_RECV_DEL |
 450                           SPI_FSI_CLOCK_CFG_SCK_DIV)) != wanted_clock_cfg)
 451                 rc = fsi_spi_write_reg(ctx, SPI_FSI_CLOCK_CFG,
 452                                        wanted_clock_cfg);
 453
 454         return rc;
 455 }
 456
 457 static int fsi_spi_transfer_one_message(struct spi_controller *ctlr,
 458                                         struct spi_message *mesg)
 459 {
 460         int rc;
 461         u8 seq_slave = SPI_FSI_SEQUENCE_SEL_SLAVE(mesg->spi->chip_select + 1);
 462         struct spi_transfer *transfer;
 463         struct fsi_spi *ctx = spi_controller_get_devdata(ctlr);
 464
 465         rc = fsi_spi_check_mux(ctx->fsi, ctx->dev);
 466         if (rc)
 467                 goto error;
 468
 469         list_for_each_entry(transfer, &mesg->transfers, transfer_list) {
 470                 struct fsi_spi_sequence seq;
 471                 struct spi_transfer *next = NULL;
 472
 473                 /* Sequencer must do shift out (tx) first. */
 474                 if (!transfer->tx_buf ||
 475                     transfer->len > (ctx->max_xfr_size + 8)) {
 476                         rc = -EINVAL;
 477                         goto error;
 478                 }
 479
 480                 dev_dbg(ctx->dev, "Start tx of %d bytes.\n", transfer->len);
 481
 482                 rc = fsi_spi_transfer_init(ctx);
 483                 if (rc < 0)
 484                         goto error;
 485
 486                 fsi_spi_sequence_init(&seq);
 487                 fsi_spi_sequence_add(&seq, seq_slave);
 488
 489                 rc = fsi_spi_sequence_transfer(ctx, &seq, transfer);
 490                 if (rc)
 491                         goto error;
 492
 493                 if (!list_is_last(&transfer->transfer_list,
 494                                   &mesg->transfers)) {
 495                         next = list_next_entry(transfer, transfer_list);
 496
 497                         /* Sequencer can only do shift in (rx) after tx. */
 498                         if (next->rx_buf) {
 499                                 if (next->len > ctx->max_xfr_size) {
 500                                         rc = -EINVAL;
 501                                         goto error;
 502                                 }
 503
 504                                 dev_dbg(ctx->dev, "Sequence rx of %d bytes.\n",
 505                                         next->len);
 506
 507                                 rc = fsi_spi_sequence_transfer(ctx, &seq,
 508                                                                next);
 509                                 if (rc)
 510                                         goto error;
 511                         } else {
 512                                 next = NULL;
 513                         }
 514                 }
 515
 516                 fsi_spi_sequence_add(&seq, SPI_FSI_SEQUENCE_SEL_SLAVE(0));
 517
 518                 rc = fsi_spi_write_reg(ctx, SPI_FSI_SEQUENCE, seq.data);
 519                 if (rc)
 520                         goto error;
 521
 522                 rc = fsi_spi_transfer_data(ctx, transfer);
 523                 if (rc)
 524                         goto error;
 525
 526                 if (next) {
 527                         rc = fsi_spi_transfer_data(ctx, next);
 528                         if (rc)
 529                                 goto error;
 530
 531                         transfer = next;
 532                 }
 533         }
 534
 535 error:
 536         mesg->status = rc;
 537         spi_finalize_current_message(ctlr);
 538
 539         return rc;
 540 }
 541
 542 static size_t fsi_spi_max_transfer_size(struct spi_device *spi)
 543 {
 544         struct fsi_spi *ctx = spi_controller_get_devdata(spi->controller);
 545
 546         return ctx->max_xfr_size;
 547 }
 548
 549 static int fsi_spi_probe(struct device *dev)
 550 {
 551         int rc;
 552         struct device_node *np;
 553         int num_controllers_registered = 0;
 554         struct fsi_device *fsi = to_fsi_dev(dev);
 555
 556         rc = fsi_spi_check_mux(fsi, dev);
 557         if (rc)
 558                 return -ENODEV;
 559
 560         for_each_available_child_of_node(dev->of_node, np) {
 561                 u32 base;
 562                 struct fsi_spi *ctx;
 563                 struct spi_controller *ctlr;
 564
 565                 if (of_property_read_u32(np, "reg", &base))
 566                         continue;
 567
 568                 ctlr = spi_alloc_master(dev, sizeof(*ctx));
 569                 if (!ctlr) {
 570                         of_node_put(np);
 571                         break;
 572                 }
 573
 574                 ctlr->dev.of_node = np;
 575                 ctlr->num_chipselect = of_get_available_child_count(np) ?: 1;
 576                 ctlr->flags = SPI_CONTROLLER_HALF_DUPLEX;
 577                 ctlr->max_transfer_size = fsi_spi_max_transfer_size;
 578                 ctlr->transfer_one_message = fsi_spi_transfer_one_message;
 579
 580                 ctx = spi_controller_get_devdata(ctlr);
 581                 ctx->dev = &ctlr->dev;
 582                 ctx->fsi = fsi;
 583                 ctx->base = base + SPI_FSI_BASE;
 584
 585                 if (of_device_is_compatible(np, "ibm,fsi2spi-restricted")) {
 586                         ctx->restricted = true;
 587                         ctx->max_xfr_size = SPI_FSI_MAX_XFR_SIZE_RESTRICTED;
 588                 } else {
 589                         ctx->restricted = false;
 590                         ctx->max_xfr_size = SPI_FSI_MAX_XFR_SIZE;
 591                 }
 592
 593                 rc = devm_spi_register_controller(dev, ctlr);
 594                 if (rc)
 595                         spi_controller_put(ctlr);
 596                 else
 597                         num_controllers_registered++;
 598         }
 599
 600         if (!num_controllers_registered)
 601                 return -ENODEV;
 602
 603         return 0;
 604 }
 605
 606 static const struct fsi_device_id fsi_spi_ids[] = {
 607         { FSI_ENGID_SPI, FSI_VERSION_ANY },
 608         { }
 609 };
 610 MODULE_DEVICE_TABLE(fsi, fsi_spi_ids);
 611
 612 static struct fsi_driver fsi_spi_driver = {
 613         .id_table = fsi_spi_ids,
 614         .drv = {
 615                 .name = "spi-fsi",
 616                 .bus = &fsi_bus_type,
 617                 .probe = fsi_spi_probe,
 618         },
 619 };
 620 module_fsi_driver(fsi_spi_driver);
 621
 622 MODULE_AUTHOR("Eddie James <eajames@linux.ibm.com>");
 623 MODULE_DESCRIPTION("FSI attached SPI controller");
 624 MODULE_LICENSE("GPL");