drivers/mfd/cros_ec_spi.c

   1 /*
   2  * ChromeOS EC multi-function device (SPI)
   3  *
   4  * Copyright (C) 2012 Google, Inc
   5  *
   6  * This software is licensed under the terms of the GNU General Public
   7  * License version 2, as published by the Free Software Foundation, and
   8  * may be copied, distributed, and modified under those terms.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  */
  15
  16 #include <linux/delay.h>
  17 #include <linux/kernel.h>
  18 #include <linux/module.h>
  19 #include <linux/mfd/cros_ec.h>
  20 #include <linux/mfd/cros_ec_commands.h>
  21 #include <linux/of.h>
  22 #include <linux/platform_device.h>
  23 #include <linux/slab.h>
  24 #include <linux/spi/spi.h>
  25
  26
  27 /* The header byte, which follows the preamble */
  28 #define EC_MSG_HEADER                   0xec
  29
  30 /*
  31  * Number of EC preamble bytes we read at a time. Since it takes
  32  * about 400-500us for the EC to respond there is not a lot of
  33  * point in tuning this. If the EC could respond faster then
  34  * we could increase this so that might expect the preamble and
  35  * message to occur in a single transaction. However, the maximum
  36  * SPI transfer size is 256 bytes, so at 5MHz we need a response
  37  * time of perhaps <320us (200 bytes / 1600 bits).
  38  */
  39 #define EC_MSG_PREAMBLE_COUNT           32
  40
  41 /*
  42  * Allow for a long time for the EC to respond.  We support i2c
  43  * tunneling and support fairly long messages for the tunnel (249
  44  * bytes long at the moment).  If we're talking to a 100 kHz device
  45  * on the other end and need to transfer ~256 bytes, then we need:
  46  *  10 us/bit * ~10 bits/byte * ~256 bytes = ~25ms
  47  *
  48  * We'll wait 4 times that to handle clock stretching and other
  49  * paranoia.
  50  *
  51  * It's pretty unlikely that we'll really see a 249 byte tunnel in
  52  * anything other than testing.  If this was more common we might
  53  * consider having slow commands like this require a GET_STATUS
  54  * wait loop.  The 'flash write' command would be another candidate
  55  * for this, clocking in at 2-3ms.
  56  */
  57 #define EC_MSG_DEADLINE_MS              100
  58
  59 /*
  60   * Time between raising the SPI chip select (for the end of a
  61   * transaction) and dropping it again (for the next transaction).
  62   * If we go too fast, the EC will miss the transaction. We know that we
  63   * need at least 70 us with the 16 MHz STM32 EC, so go with 200 us to be
  64   * safe.
  65   */
  66 #define EC_SPI_RECOVERY_TIME_NS (200 * 1000)
  67
  68 /**
  69  * struct cros_ec_spi - information about a SPI-connected EC
  70  *
  71  * @spi: SPI device we are connected to
  72  * @last_transfer_ns: time that we last finished a transfer, or 0 if there
  73  *      if no record
  74  * @end_of_msg_delay: used to set the delay_usecs on the spi_transfer that
  75  *      is sent when we want to turn off CS at the end of a transaction.
  76  */
  77 struct cros_ec_spi {
  78         struct spi_device *spi;
  79         s64 last_transfer_ns;
  80         unsigned int end_of_msg_delay;
  81 };
  82
  83 static void debug_packet(struct device *dev, const char *name, u8 *ptr,
  84                          int len)
  85 {
  86 #ifdef DEBUG
  87         int i;
  88
  89         dev_dbg(dev, "%s: ", name);
  90         for (i = 0; i < len; i++)
  91                 pr_cont(" %02x", ptr[i]);
  92
  93         pr_cont("\n");
  94 #endif
  95 }
  96
  97 static int terminate_request(struct cros_ec_device *ec_dev)
  98 {
  99         struct cros_ec_spi *ec_spi = ec_dev->priv;
 100         struct spi_message msg;
 101         struct spi_transfer trans;
 102         int ret;
 103
 104         /*
 105          * Turn off CS, possibly adding a delay to ensure the rising edge
 106          * doesn't come too soon after the end of the data.
 107          */
 108         spi_message_init(&msg);
 109         memset(&trans, 0, sizeof(trans));
 110         trans.delay_usecs = ec_spi->end_of_msg_delay;
 111         spi_message_add_tail(&trans, &msg);
 112
 113         ret = spi_sync(ec_spi->spi, &msg);
 114
 115         /* Reset end-of-response timer */
 116         ec_spi->last_transfer_ns = ktime_get_ns();
 117         if (ret < 0) {
 118                 dev_err(ec_dev->dev,
 119                         "cs-deassert spi transfer failed: %d\n",
 120                         ret);
 121         }
 122
 123         return ret;
 124 }
 125
 126 /**
 127  * receive_n_bytes - receive n bytes from the EC.
 128  *
 129  * Assumes buf is a pointer into the ec_dev->din buffer
 130  */
 131 static int receive_n_bytes(struct cros_ec_device *ec_dev, u8 *buf, int n)
 132 {
 133         struct cros_ec_spi *ec_spi = ec_dev->priv;
 134         struct spi_transfer trans;
 135         struct spi_message msg;
 136         int ret;
 137
 138         BUG_ON(buf - ec_dev->din + n > ec_dev->din_size);
 139
 140         memset(&trans, 0, sizeof(trans));
 141         trans.cs_change = 1;
 142         trans.rx_buf = buf;
 143         trans.len = n;
 144
 145         spi_message_init(&msg);
 146         spi_message_add_tail(&trans, &msg);
 147         ret = spi_sync(ec_spi->spi, &msg);
 148         if (ret < 0)
 149                 dev_err(ec_dev->dev, "spi transfer failed: %d\n", ret);
 150
 151         return ret;
 152 }
 153
 154 /**
 155  * cros_ec_spi_receive_packet - Receive a packet from the EC.
 156  *
 157  * This function has two phases: reading the preamble bytes (since if we read
 158  * data from the EC before it is ready to send, we just get preamble) and
 159  * reading the actual message.
 160  *
 161  * The received data is placed into ec_dev->din.
 162  *
 163  * @ec_dev: ChromeOS EC device
 164  * @need_len: Number of message bytes we need to read
 165  */
 166 static int cros_ec_spi_receive_packet(struct cros_ec_device *ec_dev,
 167                                       int need_len)
 168 {
 169         struct ec_host_response *response;
 170         u8 *ptr, *end;
 171         int ret;
 172         unsigned long deadline;
 173         int todo;
 174
 175         BUG_ON(EC_MSG_PREAMBLE_COUNT > ec_dev->din_size);
 176
 177         /* Receive data until we see the header byte */
 178         deadline = jiffies + msecs_to_jiffies(EC_MSG_DEADLINE_MS);
 179         while (true) {
 180                 unsigned long start_jiffies = jiffies;
 181
 182                 ret = receive_n_bytes(ec_dev,
 183                                       ec_dev->din,
 184                                       EC_MSG_PREAMBLE_COUNT);
 185                 if (ret < 0)
 186                         return ret;
 187
 188                 ptr = ec_dev->din;
 189                 for (end = ptr + EC_MSG_PREAMBLE_COUNT; ptr != end; ptr++) {
 190                         if (*ptr == EC_SPI_FRAME_START) {
 191                                 dev_dbg(ec_dev->dev, "msg found at %zd\n",
 192                                         ptr - ec_dev->din);
 193                                 break;
 194                         }
 195                 }
 196                 if (ptr != end)
 197                         break;
 198
 199                 /*
 200                  * Use the time at the start of the loop as a timeout.  This
 201                  * gives us one last shot at getting the transfer and is useful
 202                  * in case we got context switched out for a while.
 203                  */
 204                 if (time_after(start_jiffies, deadline)) {
 205                         dev_warn(ec_dev->dev, "EC failed to respond in time\n");
 206                         return -ETIMEDOUT;
 207                 }
 208         }
 209
 210         /*
 211          * ptr now points to the header byte. Copy any valid data to the
 212          * start of our buffer
 213          */
 214         todo = end - ++ptr;
 215         BUG_ON(todo < 0 || todo > ec_dev->din_size);
 216         todo = min(todo, need_len);
 217         memmove(ec_dev->din, ptr, todo);
 218         ptr = ec_dev->din + todo;
 219         dev_dbg(ec_dev->dev, "need %d, got %d bytes from preamble\n",
 220                 need_len, todo);
 221         need_len -= todo;
 222
 223         /* If the entire response struct wasn't read, get the rest of it. */
 224         if (todo < sizeof(*response)) {
 225                 ret = receive_n_bytes(ec_dev, ptr, sizeof(*response) - todo);
 226                 if (ret < 0)
 227                         return -EBADMSG;
 228                 ptr += (sizeof(*response) - todo);
 229                 todo = sizeof(*response);
 230         }
 231
 232         response = (struct ec_host_response *)ec_dev->din;
 233
 234         /* Abort if data_len is too large. */
 235         if (response->data_len > ec_dev->din_size)
 236                 return -EMSGSIZE;
 237
 238         /* Receive data until we have it all */
 239         while (need_len > 0) {
 240                 /*
 241                  * We can't support transfers larger than the SPI FIFO size
 242                  * unless we have DMA. We don't have DMA on the ISP SPI ports
 243                  * for Exynos. We need a way of asking SPI driver for
 244                  * maximum-supported transfer size.
 245                  */
 246                 todo = min(need_len, 256);
 247                 dev_dbg(ec_dev->dev, "loop, todo=%d, need_len=%d, ptr=%zd\n",
 248                         todo, need_len, ptr - ec_dev->din);
 249
 250                 ret = receive_n_bytes(ec_dev, ptr, todo);
 251                 if (ret < 0)
 252                         return ret;
 253
 254                 ptr += todo;
 255                 need_len -= todo;
 256         }
 257
 258         dev_dbg(ec_dev->dev, "loop done, ptr=%zd\n", ptr - ec_dev->din);
 259
 260         return 0;
 261 }
 262
 263 /**
 264  * cros_ec_spi_receive_response - Receive a response from the EC.
 265  *
 266  * This function has two phases: reading the preamble bytes (since if we read
 267  * data from the EC before it is ready to send, we just get preamble) and
 268  * reading the actual message.
 269  *
 270  * The received data is placed into ec_dev->din.
 271  *
 272  * @ec_dev: ChromeOS EC device
 273  * @need_len: Number of message bytes we need to read
 274  */
 275 static int cros_ec_spi_receive_response(struct cros_ec_device *ec_dev,
 276                                         int need_len)
 277 {
 278         u8 *ptr, *end;
 279         int ret;
 280         unsigned long deadline;
 281         int todo;
 282
 283         BUG_ON(EC_MSG_PREAMBLE_COUNT > ec_dev->din_size);
 284
 285         /* Receive data until we see the header byte */
 286         deadline = jiffies + msecs_to_jiffies(EC_MSG_DEADLINE_MS);
 287         while (true) {
 288                 unsigned long start_jiffies = jiffies;
 289
 290                 ret = receive_n_bytes(ec_dev,
 291                                       ec_dev->din,
 292                                       EC_MSG_PREAMBLE_COUNT);
 293                 if (ret < 0)
 294                         return ret;
 295
 296                 ptr = ec_dev->din;
 297                 for (end = ptr + EC_MSG_PREAMBLE_COUNT; ptr != end; ptr++) {
 298                         if (*ptr == EC_SPI_FRAME_START) {
 299                                 dev_dbg(ec_dev->dev, "msg found at %zd\n",
 300                                         ptr - ec_dev->din);
 301                                 break;
 302                         }
 303                 }
 304                 if (ptr != end)
 305                         break;
 306
 307                 /*
 308                  * Use the time at the start of the loop as a timeout.  This
 309                  * gives us one last shot at getting the transfer and is useful
 310                  * in case we got context switched out for a while.
 311                  */
 312                 if (time_after(start_jiffies, deadline)) {
 313                         dev_warn(ec_dev->dev, "EC failed to respond in time\n");
 314                         return -ETIMEDOUT;
 315                 }
 316         }
 317
 318         /*
 319          * ptr now points to the header byte. Copy any valid data to the
 320          * start of our buffer
 321          */
 322         todo = end - ++ptr;
 323         BUG_ON(todo < 0 || todo > ec_dev->din_size);
 324         todo = min(todo, need_len);
 325         memmove(ec_dev->din, ptr, todo);
 326         ptr = ec_dev->din + todo;
 327         dev_dbg(ec_dev->dev, "need %d, got %d bytes from preamble\n",
 328                  need_len, todo);
 329         need_len -= todo;
 330
 331         /* Receive data until we have it all */
 332         while (need_len > 0) {
 333                 /*
 334                  * We can't support transfers larger than the SPI FIFO size
 335                  * unless we have DMA. We don't have DMA on the ISP SPI ports
 336                  * for Exynos. We need a way of asking SPI driver for
 337                  * maximum-supported transfer size.
 338                  */
 339                 todo = min(need_len, 256);
 340                 dev_dbg(ec_dev->dev, "loop, todo=%d, need_len=%d, ptr=%zd\n",
 341                         todo, need_len, ptr - ec_dev->din);
 342
 343                 ret = receive_n_bytes(ec_dev, ptr, todo);
 344                 if (ret < 0)
 345                         return ret;
 346
 347                 debug_packet(ec_dev->dev, "interim", ptr, todo);
 348                 ptr += todo;
 349                 need_len -= todo;
 350         }
 351
 352         dev_dbg(ec_dev->dev, "loop done, ptr=%zd\n", ptr - ec_dev->din);
 353
 354         return 0;
 355 }
 356
 357 /**
 358  * cros_ec_pkt_xfer_spi - Transfer a packet over SPI and receive the reply
 359  *
 360  * @ec_dev: ChromeOS EC device
 361  * @ec_msg: Message to transfer
 362  */
 363 static int cros_ec_pkt_xfer_spi(struct cros_ec_device *ec_dev,
 364                                 struct cros_ec_command *ec_msg)
 365 {
 366         struct ec_host_request *request;
 367         struct ec_host_response *response;
 368         struct cros_ec_spi *ec_spi = ec_dev->priv;
 369         struct spi_transfer trans;
 370         struct spi_message msg;
 371         int i, len;
 372         u8 *ptr;
 373         u8 *rx_buf;
 374         u8 sum;
 375         int ret = 0, final_ret;
 376
 377         len = cros_ec_prepare_tx(ec_dev, ec_msg);
 378         request = (struct ec_host_request *)ec_dev->dout;
 379         dev_dbg(ec_dev->dev, "prepared, len=%d\n", len);
 380
 381         /* If it's too soon to do another transaction, wait */
 382         if (ec_spi->last_transfer_ns) {
 383                 unsigned long delay;    /* The delay completed so far */
 384
 385                 delay = ktime_get_ns() - ec_spi->last_transfer_ns;
 386                 if (delay < EC_SPI_RECOVERY_TIME_NS)
 387                         ndelay(EC_SPI_RECOVERY_TIME_NS - delay);
 388         }
 389
 390         rx_buf = kzalloc(len, GFP_KERNEL);
 391         if (!rx_buf) {
 392                 ret = -ENOMEM;
 393                 goto exit;
 394         }
 395
 396         /* Transmit phase - send our message */
 397         memset(&trans, 0, sizeof(trans));
 398         trans.tx_buf = ec_dev->dout;
 399         trans.rx_buf = rx_buf;
 400         trans.len = len;
 401         trans.cs_change = 1;
 402         spi_message_init(&msg);
 403         spi_message_add_tail(&trans, &msg);
 404         ret = spi_sync(ec_spi->spi, &msg);
 405
 406         /* Get the response */
 407         if (!ret) {
 408                 /* Verify that EC can process command */
 409                 for (i = 0; i < len; i++) {
 410                         switch (rx_buf[i]) {
 411                         case EC_SPI_PAST_END:
 412                         case EC_SPI_RX_BAD_DATA:
 413                         case EC_SPI_NOT_READY:
 414                                 ret = -EAGAIN;
 415                                 ec_msg->result = EC_RES_IN_PROGRESS;
 416                         default:
 417                                 break;
 418                         }
 419                         if (ret)
 420                                 break;
 421                 }
 422                 if (!ret)
 423                         ret = cros_ec_spi_receive_packet(ec_dev,
 424                                         ec_msg->insize + sizeof(*response));
 425         } else {
 426                 dev_err(ec_dev->dev, "spi transfer failed: %d\n", ret);
 427         }
 428
 429         final_ret = terminate_request(ec_dev);
 430         if (!ret)
 431                 ret = final_ret;
 432         if (ret < 0)
 433                 goto exit;
 434
 435         ptr = ec_dev->din;
 436
 437         /* check response error code */
 438         response = (struct ec_host_response *)ptr;
 439         ec_msg->result = response->result;
 440
 441         ret = cros_ec_check_result(ec_dev, ec_msg);
 442         if (ret)
 443                 goto exit;
 444
 445         len = response->data_len;
 446         sum = 0;
 447         if (len > ec_msg->insize) {
 448                 dev_err(ec_dev->dev, "packet too long (%d bytes, expected %d)",
 449                         len, ec_msg->insize);
 450                 ret = -EMSGSIZE;
 451                 goto exit;
 452         }
 453
 454         for (i = 0; i < sizeof(*response); i++)
 455                 sum += ptr[i];
 456
 457         /* copy response packet payload and compute checksum */
 458         memcpy(ec_msg->data, ptr + sizeof(*response), len);
 459         for (i = 0; i < len; i++)
 460                 sum += ec_msg->data[i];
 461
 462         if (sum) {
 463                 dev_err(ec_dev->dev,
 464                         "bad packet checksum, calculated %x\n",
 465                         sum);
 466                 ret = -EBADMSG;
 467                 goto exit;
 468         }
 469
 470         ret = len;
 471 exit:
 472         kfree(rx_buf);
 473         if (ec_msg->command == EC_CMD_REBOOT_EC)
 474                 msleep(EC_REBOOT_DELAY_MS);
 475
 476         return ret;
 477 }
 478
 479 /**
 480  * cros_ec_cmd_xfer_spi - Transfer a message over SPI and receive the reply
 481  *
 482  * @ec_dev: ChromeOS EC device
 483  * @ec_msg: Message to transfer
 484  */
 485 static int cros_ec_cmd_xfer_spi(struct cros_ec_device *ec_dev,
 486                                 struct cros_ec_command *ec_msg)
 487 {
 488         struct cros_ec_spi *ec_spi = ec_dev->priv;
 489         struct spi_transfer trans;
 490         struct spi_message msg;
 491         int i, len;
 492         u8 *ptr;
 493         u8 *rx_buf;
 494         int sum;
 495         int ret = 0, final_ret;
 496
 497         len = cros_ec_prepare_tx(ec_dev, ec_msg);
 498         dev_dbg(ec_dev->dev, "prepared, len=%d\n", len);
 499
 500         /* If it's too soon to do another transaction, wait */
 501         if (ec_spi->last_transfer_ns) {
 502                 unsigned long delay;    /* The delay completed so far */
 503
 504                 delay = ktime_get_ns() - ec_spi->last_transfer_ns;
 505                 if (delay < EC_SPI_RECOVERY_TIME_NS)
 506                         ndelay(EC_SPI_RECOVERY_TIME_NS - delay);
 507         }
 508
 509         rx_buf = kzalloc(len, GFP_KERNEL);
 510         if (!rx_buf) {
 511                 ret = -ENOMEM;
 512                 goto exit;
 513         }
 514
 515         /* Transmit phase - send our message */
 516         debug_packet(ec_dev->dev, "out", ec_dev->dout, len);
 517         memset(&trans, 0, sizeof(trans));
 518         trans.tx_buf = ec_dev->dout;
 519         trans.rx_buf = rx_buf;
 520         trans.len = len;
 521         trans.cs_change = 1;
 522         spi_message_init(&msg);
 523         spi_message_add_tail(&trans, &msg);
 524         ret = spi_sync(ec_spi->spi, &msg);
 525
 526         /* Get the response */
 527         if (!ret) {
 528                 /* Verify that EC can process command */
 529                 for (i = 0; i < len; i++) {
 530                         switch (rx_buf[i]) {
 531                         case EC_SPI_PAST_END:
 532                         case EC_SPI_RX_BAD_DATA:
 533                         case EC_SPI_NOT_READY:
 534                                 ret = -EAGAIN;
 535                                 ec_msg->result = EC_RES_IN_PROGRESS;
 536                         default:
 537                                 break;
 538                         }
 539                         if (ret)
 540                                 break;
 541                 }
 542                 if (!ret)
 543                         ret = cros_ec_spi_receive_response(ec_dev,
 544                                         ec_msg->insize + EC_MSG_TX_PROTO_BYTES);
 545         } else {
 546                 dev_err(ec_dev->dev, "spi transfer failed: %d\n", ret);
 547         }
 548
 549         final_ret = terminate_request(ec_dev);
 550         if (!ret)
 551                 ret = final_ret;
 552         if (ret < 0)
 553                 goto exit;
 554
 555         ptr = ec_dev->din;
 556
 557         /* check response error code */
 558         ec_msg->result = ptr[0];
 559         ret = cros_ec_check_result(ec_dev, ec_msg);
 560         if (ret)
 561                 goto exit;
 562
 563         len = ptr[1];
 564         sum = ptr[0] + ptr[1];
 565         if (len > ec_msg->insize) {
 566                 dev_err(ec_dev->dev, "packet too long (%d bytes, expected %d)",
 567                         len, ec_msg->insize);
 568                 ret = -ENOSPC;
 569                 goto exit;
 570         }
 571
 572         /* copy response packet payload and compute checksum */
 573         for (i = 0; i < len; i++) {
 574                 sum += ptr[i + 2];
 575                 if (ec_msg->insize)
 576                         ec_msg->data[i] = ptr[i + 2];
 577         }
 578         sum &= 0xff;
 579
 580         debug_packet(ec_dev->dev, "in", ptr, len + 3);
 581
 582         if (sum != ptr[len + 2]) {
 583                 dev_err(ec_dev->dev,
 584                         "bad packet checksum, expected %02x, got %02x\n",
 585                         sum, ptr[len + 2]);
 586                 ret = -EBADMSG;
 587                 goto exit;
 588         }
 589
 590         ret = len;
 591 exit:
 592         kfree(rx_buf);
 593         if (ec_msg->command == EC_CMD_REBOOT_EC)
 594                 msleep(EC_REBOOT_DELAY_MS);
 595
 596         return ret;
 597 }
 598
 599 static void cros_ec_spi_dt_probe(struct cros_ec_spi *ec_spi, struct device *dev)
 600 {
 601         struct device_node *np = dev->of_node;
 602         u32 val;
 603         int ret;
 604
 605         ret = of_property_read_u32(np, "google,cros-ec-spi-msg-delay", &val);
 606         if (!ret)
 607                 ec_spi->end_of_msg_delay = val;
 608 }
 609
 610 static int cros_ec_spi_probe(struct spi_device *spi)
 611 {
 612         struct device *dev = &spi->dev;
 613         struct cros_ec_device *ec_dev;
 614         struct cros_ec_spi *ec_spi;
 615         int err;
 616
 617         spi->bits_per_word = 8;
 618         spi->mode = SPI_MODE_0;
 619         err = spi_setup(spi);
 620         if (err < 0)
 621                 return err;
 622
 623         ec_spi = devm_kzalloc(dev, sizeof(*ec_spi), GFP_KERNEL);
 624         if (ec_spi == NULL)
 625                 return -ENOMEM;
 626         ec_spi->spi = spi;
 627         ec_dev = devm_kzalloc(dev, sizeof(*ec_dev), GFP_KERNEL);
 628         if (!ec_dev)
 629                 return -ENOMEM;
 630
 631         /* Check for any DT properties */
 632         cros_ec_spi_dt_probe(ec_spi, dev);
 633
 634         spi_set_drvdata(spi, ec_dev);
 635         ec_dev->dev = dev;
 636         ec_dev->priv = ec_spi;
 637         ec_dev->irq = spi->irq;
 638         ec_dev->cmd_xfer = cros_ec_cmd_xfer_spi;
 639         ec_dev->pkt_xfer = cros_ec_pkt_xfer_spi;
 640         ec_dev->phys_name = dev_name(&ec_spi->spi->dev);
 641         ec_dev->din_size = EC_MSG_PREAMBLE_COUNT +
 642                            sizeof(struct ec_host_response) +
 643                            sizeof(struct ec_response_get_protocol_info);
 644         ec_dev->dout_size = sizeof(struct ec_host_request);
 645
 646
 647         err = cros_ec_register(ec_dev);
 648         if (err) {
 649                 dev_err(dev, "cannot register EC\n");
 650                 return err;
 651         }
 652
 653         device_init_wakeup(&spi->dev, true);
 654
 655         return 0;
 656 }
 657
 658 static int cros_ec_spi_remove(struct spi_device *spi)
 659 {
 660         struct cros_ec_device *ec_dev;
 661
 662         ec_dev = spi_get_drvdata(spi);
 663         cros_ec_remove(ec_dev);
 664
 665         return 0;
 666 }
 667
 668 #ifdef CONFIG_PM_SLEEP
 669 static int cros_ec_spi_suspend(struct device *dev)
 670 {
 671         struct cros_ec_device *ec_dev = dev_get_drvdata(dev);
 672
 673         return cros_ec_suspend(ec_dev);
 674 }
 675
 676 static int cros_ec_spi_resume(struct device *dev)
 677 {
 678         struct cros_ec_device *ec_dev = dev_get_drvdata(dev);
 679
 680         return cros_ec_resume(ec_dev);
 681 }
 682 #endif
 683
 684 static SIMPLE_DEV_PM_OPS(cros_ec_spi_pm_ops, cros_ec_spi_suspend,
 685                          cros_ec_spi_resume);
 686
 687 static const struct spi_device_id cros_ec_spi_id[] = {
 688         { "cros-ec-spi", 0 },
 689         { }
 690 };
 691 MODULE_DEVICE_TABLE(spi, cros_ec_spi_id);
 692
 693 static struct spi_driver cros_ec_driver_spi = {
 694         .driver = {
 695                 .name   = "cros-ec-spi",
 696                 .owner  = THIS_MODULE,
 697                 .pm     = &cros_ec_spi_pm_ops,
 698         },
 699         .probe          = cros_ec_spi_probe,
 700         .remove         = cros_ec_spi_remove,
 701         .id_table       = cros_ec_spi_id,
 702 };
 703
 704 module_spi_driver(cros_ec_driver_spi);
 705
 706 MODULE_LICENSE("GPL v2");
 707 MODULE_DESCRIPTION("ChromeOS EC multi function device (SPI)");