cros_ec_ishtp.c 20.4 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762
// SPDX-License-Identifier: GPL-2.0
// ISHTP interface for ChromeOS Embedded Controller
//
// Copyright (c) 2019, Intel Corporation.
//
// ISHTP client driver for talking to the Chrome OS EC firmware running
// on Intel Integrated Sensor Hub (ISH) using the ISH Transport protocol
// (ISH-TP).

#include <linux/delay.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/platform_data/cros_ec_commands.h>
#include <linux/platform_data/cros_ec_proto.h>
#include <linux/intel-ish-client-if.h>

/*
 * ISH TX/RX ring buffer pool size
 *
 * The AP->ISH messages and corresponding ISH->AP responses are
 * serialized. We need 1 TX and 1 RX buffer for these.
 *
 * The MKBP ISH->AP events are serialized. We need one additional RX
 * buffer for them.
 */
#define CROS_ISH_CL_TX_RING_SIZE		8
#define CROS_ISH_CL_RX_RING_SIZE		8

/* ISH CrOS EC Host Commands */
enum cros_ec_ish_channel {
	CROS_EC_COMMAND = 1,			/* AP->ISH message */
	CROS_MKBP_EVENT = 2,			/* ISH->AP events */
};

/*
 * ISH firmware timeout for 1 message send failure is 1Hz, and the
 * firmware will retry 2 times, so 3Hz is used for timeout.
 */
#define ISHTP_SEND_TIMEOUT			(3 * HZ)

/* ISH Transport CrOS EC ISH client unique GUID */
static const guid_t cros_ish_guid =
	GUID_INIT(0x7b7154d0, 0x56f4, 0x4bdc,
		  0xb0, 0xd8, 0x9e, 0x7c, 0xda,	0xe0, 0xd6, 0xa0);

struct header {
	u8 channel;
	u8 status;
	u8 reserved[2];
} __packed;

struct cros_ish_out_msg {
	struct header hdr;
	struct ec_host_request ec_request;
} __packed;

struct cros_ish_in_msg {
	struct header hdr;
	struct ec_host_response ec_response;
} __packed;

#define IN_MSG_EC_RESPONSE_PREAMBLE					\
	offsetof(struct cros_ish_in_msg, ec_response)

#define OUT_MSG_EC_REQUEST_PREAMBLE					\
	offsetof(struct cros_ish_out_msg, ec_request)

#define cl_data_to_dev(client_data) ishtp_device((client_data)->cl_device)

/*
 * The Read-Write Semaphore is used to prevent message TX or RX while
 * the ishtp client is being initialized or undergoing reset.
 *
 * The readers are the kernel function calls responsible for IA->ISH
 * and ISH->AP messaging.
 *
 * The writers are .reset() and .probe() function.
 */
DECLARE_RWSEM(init_lock);

/**
 * struct response_info - Encapsulate firmware response related
 * information for passing between function ish_send() and
 * process_recv() callback.
 *
 * @data: Copy the data received from firmware here.
 * @max_size: Max size allocated for the @data buffer. If the received
 * data exceeds this value, we log an error.
 * @size: Actual size of data received from firmware.
 * @error: 0 for success, negative error code for a failure in process_recv().
 * @received: Set to true on receiving a valid firmware	response to host command
 * @wait_queue: Wait queue for host to wait for firmware response.
 */
struct response_info {
	void *data;
	size_t max_size;
	size_t size;
	int error;
	bool received;
	wait_queue_head_t wait_queue;
};

/**
 * struct ishtp_cl_data - Encapsulate per ISH TP Client.
 *
 * @cros_ish_cl: ISHTP firmware client instance.
 * @cl_device: ISHTP client device instance.
 * @response: Response info passing between ish_send() and process_recv().
 * @work_ishtp_reset: Work queue reset handling.
 * @work_ec_evt: Work queue for EC events.
 * @ec_dev: CrOS EC MFD device.
 *
 * This structure is used to store per client data.
 */
struct ishtp_cl_data {
	struct ishtp_cl *cros_ish_cl;
	struct ishtp_cl_device *cl_device;

	/*
	 * Used for passing firmware response information between
	 * ish_send() and process_recv() callback.
	 */
	struct response_info response;

	struct work_struct work_ishtp_reset;
	struct work_struct work_ec_evt;
	struct cros_ec_device *ec_dev;
};

/**
 * ish_evt_handler - ISH to AP event handler
 * @work: Work struct
 */
static void ish_evt_handler(struct work_struct *work)
{
	struct ishtp_cl_data *client_data =
		container_of(work, struct ishtp_cl_data, work_ec_evt);
	struct cros_ec_device *ec_dev = client_data->ec_dev;

	if (cros_ec_get_next_event(ec_dev, NULL) > 0) {
		blocking_notifier_call_chain(&ec_dev->event_notifier,
					     0, ec_dev);
	}
}

/**
 * ish_send() - Send message from host to firmware
 *
 * @client_data: Client data instance
 * @out_msg: Message buffer to be sent to firmware
 * @out_size: Size of out going message
 * @in_msg: Message buffer where the incoming data is copied. This buffer
 * is allocated by calling
 * @in_size: Max size of incoming message
 *
 * Return: Number of bytes copied in the in_msg on success, negative
 * error code on failure.
 */
static int ish_send(struct ishtp_cl_data *client_data,
		    u8 *out_msg, size_t out_size,
		    u8 *in_msg, size_t in_size)
{
	int rv;
	struct header *out_hdr = (struct header *)out_msg;
	struct ishtp_cl *cros_ish_cl = client_data->cros_ish_cl;

	dev_dbg(cl_data_to_dev(client_data),
		"%s: channel=%02u status=%02u\n",
		__func__, out_hdr->channel, out_hdr->status);

	/* Setup for incoming response */
	client_data->response.data = in_msg;
	client_data->response.max_size = in_size;
	client_data->response.error = 0;
	client_data->response.received = false;

	rv = ishtp_cl_send(cros_ish_cl, out_msg, out_size);
	if (rv) {
		dev_err(cl_data_to_dev(client_data),
			"ishtp_cl_send error %d\n", rv);
		return rv;
	}

	wait_event_interruptible_timeout(client_data->response.wait_queue,
					 client_data->response.received,
					 ISHTP_SEND_TIMEOUT);
	if (!client_data->response.received) {
		dev_err(cl_data_to_dev(client_data),
			"Timed out for response to host message\n");
		return -ETIMEDOUT;
	}

	if (client_data->response.error < 0)
		return client_data->response.error;

	return client_data->response.size;
}

/**
 * process_recv() - Received and parse incoming packet
 * @cros_ish_cl: Client instance to get stats
 * @rb_in_proc: Host interface message buffer
 *
 * Parse the incoming packet. If it is a response packet then it will
 * update per instance flags and wake up the caller waiting to for the
 * response. If it is an event packet then it will schedule event work.
 */
static void process_recv(struct ishtp_cl *cros_ish_cl,
			 struct ishtp_cl_rb *rb_in_proc)
{
	size_t data_len = rb_in_proc->buf_idx;
	struct ishtp_cl_data *client_data =
		ishtp_get_client_data(cros_ish_cl);
	struct device *dev = cl_data_to_dev(client_data);
	struct cros_ish_in_msg *in_msg =
		(struct cros_ish_in_msg *)rb_in_proc->buffer.data;

	/* Proceed only if reset or init is not in progress */
	if (!down_read_trylock(&init_lock)) {
		/* Free the buffer */
		ishtp_cl_io_rb_recycle(rb_in_proc);
		dev_warn(dev,
			 "Host is not ready to receive incoming messages\n");
		return;
	}

	/*
	 * All firmware messages contain a header. Check the buffer size
	 * before accessing elements inside.
	 */
	if (!rb_in_proc->buffer.data) {
		dev_warn(dev, "rb_in_proc->buffer.data returned null");
		client_data->response.error = -EBADMSG;
		goto end_error;
	}

	if (data_len < sizeof(struct header)) {
		dev_err(dev, "data size %zu is less than header %zu\n",
			data_len, sizeof(struct header));
		client_data->response.error = -EMSGSIZE;
		goto end_error;
	}

	dev_dbg(dev, "channel=%02u status=%02u\n",
		in_msg->hdr.channel, in_msg->hdr.status);

	switch (in_msg->hdr.channel) {
	case CROS_EC_COMMAND:
		/* Sanity check */
		if (!client_data->response.data) {
			dev_err(dev,
				"Receiving buffer is null. Should be allocated by calling function\n");
			client_data->response.error = -EINVAL;
			goto error_wake_up;
		}

		if (client_data->response.received) {
			dev_err(dev,
				"Previous firmware message not yet processed\n");
			client_data->response.error = -EINVAL;
			goto error_wake_up;
		}

		if (data_len > client_data->response.max_size) {
			dev_err(dev,
				"Received buffer size %zu is larger than allocated buffer %zu\n",
				data_len, client_data->response.max_size);
			client_data->response.error = -EMSGSIZE;
			goto error_wake_up;
		}

		if (in_msg->hdr.status) {
			dev_err(dev, "firmware returned status %d\n",
				in_msg->hdr.status);
			client_data->response.error = -EIO;
			goto error_wake_up;
		}

		/* Update the actual received buffer size */
		client_data->response.size = data_len;

		/*
		 * Copy the buffer received in firmware response for the
		 * calling thread.
		 */
		memcpy(client_data->response.data,
		       rb_in_proc->buffer.data, data_len);

		/* Set flag before waking up the caller */
		client_data->response.received = true;
error_wake_up:
		/* Wake the calling thread */
		wake_up_interruptible(&client_data->response.wait_queue);

		break;

	case CROS_MKBP_EVENT:
		/* The event system doesn't send any data in buffer */
		schedule_work(&client_data->work_ec_evt);

		break;

	default:
		dev_err(dev, "Invalid channel=%02d\n", in_msg->hdr.channel);
	}

end_error:
	/* Free the buffer */
	ishtp_cl_io_rb_recycle(rb_in_proc);

	up_read(&init_lock);
}

/**
 * ish_event_cb() - bus driver callback for incoming message
 * @cl_device: ISHTP client device for which this message is targeted.
 *
 * Remove the packet from the list and process the message by calling
 * process_recv.
 */
static void ish_event_cb(struct ishtp_cl_device *cl_device)
{
	struct ishtp_cl_rb *rb_in_proc;
	struct ishtp_cl	*cros_ish_cl = ishtp_get_drvdata(cl_device);

	while ((rb_in_proc = ishtp_cl_rx_get_rb(cros_ish_cl)) != NULL) {
		/* Decide what to do with received data */
		process_recv(cros_ish_cl, rb_in_proc);
	}
}

/**
 * cros_ish_init() - Init function for ISHTP client
 * @cros_ish_cl: ISHTP client instance
 *
 * This function complete the initializtion of the client.
 *
 * Return: 0 for success, negative error code for failure.
 */
static int cros_ish_init(struct ishtp_cl *cros_ish_cl)
{
	int rv;
	struct ishtp_device *dev;
	struct ishtp_fw_client *fw_client;
	struct ishtp_cl_data *client_data = ishtp_get_client_data(cros_ish_cl);

	rv = ishtp_cl_link(cros_ish_cl);
	if (rv) {
		dev_err(cl_data_to_dev(client_data),
			"ishtp_cl_link failed\n");
		return rv;
	}

	dev = ishtp_get_ishtp_device(cros_ish_cl);

	/* Connect to firmware client */
	ishtp_set_tx_ring_size(cros_ish_cl, CROS_ISH_CL_TX_RING_SIZE);
	ishtp_set_rx_ring_size(cros_ish_cl, CROS_ISH_CL_RX_RING_SIZE);

	fw_client = ishtp_fw_cl_get_client(dev, &cros_ish_guid);
	if (!fw_client) {
		dev_err(cl_data_to_dev(client_data),
			"ish client uuid not found\n");
		rv = -ENOENT;
		goto err_cl_unlink;
	}

	ishtp_cl_set_fw_client_id(cros_ish_cl,
				  ishtp_get_fw_client_id(fw_client));
	ishtp_set_connection_state(cros_ish_cl, ISHTP_CL_CONNECTING);

	rv = ishtp_cl_connect(cros_ish_cl);
	if (rv) {
		dev_err(cl_data_to_dev(client_data),
			"client connect fail\n");
		goto err_cl_unlink;
	}

	ishtp_register_event_cb(client_data->cl_device, ish_event_cb);
	return 0;

err_cl_unlink:
	ishtp_cl_unlink(cros_ish_cl);
	return rv;
}

/**
 * cros_ish_deinit() - Deinit function for ISHTP client
 * @cros_ish_cl: ISHTP client instance
 *
 * Unlink and free cros_ec client
 */
static void cros_ish_deinit(struct ishtp_cl *cros_ish_cl)
{
	ishtp_set_connection_state(cros_ish_cl, ISHTP_CL_DISCONNECTING);
	ishtp_cl_disconnect(cros_ish_cl);
	ishtp_cl_unlink(cros_ish_cl);
	ishtp_cl_flush_queues(cros_ish_cl);

	/* Disband and free all Tx and Rx client-level rings */
	ishtp_cl_free(cros_ish_cl);
}

/**
 * prepare_cros_ec_rx() - Check & prepare receive buffer
 * @ec_dev: CrOS EC MFD device.
 * @in_msg: Incoming message buffer
 * @msg: cros_ec command used to send & receive data
 *
 * Return: 0 for success, negative error code for failure.
 *
 * Check the received buffer. Convert to cros_ec_command format.
 */
static int prepare_cros_ec_rx(struct cros_ec_device *ec_dev,
			      const struct cros_ish_in_msg *in_msg,
			      struct cros_ec_command *msg)
{
	u8 sum = 0;
	int i, rv, offset;

	/* Check response error code */
	msg->result = in_msg->ec_response.result;
	rv = cros_ec_check_result(ec_dev, msg);
	if (rv < 0)
		return rv;

	if (in_msg->ec_response.data_len > msg->insize) {
		dev_err(ec_dev->dev, "Packet too long (%d bytes, expected %d)",
			in_msg->ec_response.data_len, msg->insize);
		return -ENOSPC;
	}

	/* Copy response packet payload and compute checksum */
	for (i = 0; i < sizeof(struct ec_host_response); i++)
		sum += ((u8 *)in_msg)[IN_MSG_EC_RESPONSE_PREAMBLE + i];

	offset = sizeof(struct cros_ish_in_msg);
	for (i = 0; i < in_msg->ec_response.data_len; i++)
		sum += msg->data[i] = ((u8 *)in_msg)[offset + i];

	if (sum) {
		dev_dbg(ec_dev->dev, "Bad received packet checksum %d\n", sum);
		return -EBADMSG;
	}

	return 0;
}

static int cros_ec_pkt_xfer_ish(struct cros_ec_device *ec_dev,
				struct cros_ec_command *msg)
{
	int rv;
	struct ishtp_cl *cros_ish_cl = ec_dev->priv;
	struct ishtp_cl_data *client_data = ishtp_get_client_data(cros_ish_cl);
	struct device *dev = cl_data_to_dev(client_data);
	struct cros_ish_in_msg *in_msg = (struct cros_ish_in_msg *)ec_dev->din;
	struct cros_ish_out_msg *out_msg =
		(struct cros_ish_out_msg *)ec_dev->dout;
	size_t in_size = sizeof(struct cros_ish_in_msg) + msg->insize;
	size_t out_size = sizeof(struct cros_ish_out_msg) + msg->outsize;

	/* Sanity checks */
	if (in_size > ec_dev->din_size) {
		dev_err(dev,
			"Incoming payload size %zu is too large for ec_dev->din_size %d\n",
			in_size, ec_dev->din_size);
		return -EMSGSIZE;
	}

	if (out_size > ec_dev->dout_size) {
		dev_err(dev,
			"Outgoing payload size %zu is too large for ec_dev->dout_size %d\n",
			out_size, ec_dev->dout_size);
		return -EMSGSIZE;
	}

	/* Proceed only if reset-init is not in progress */
	if (!down_read_trylock(&init_lock)) {
		dev_warn(dev,
			 "Host is not ready to send messages to ISH. Try again\n");
		return -EAGAIN;
	}

	/* Prepare the package to be sent over ISH TP */
	out_msg->hdr.channel = CROS_EC_COMMAND;
	out_msg->hdr.status = 0;

	ec_dev->dout += OUT_MSG_EC_REQUEST_PREAMBLE;
	cros_ec_prepare_tx(ec_dev, msg);
	ec_dev->dout -= OUT_MSG_EC_REQUEST_PREAMBLE;

	dev_dbg(dev,
		"out_msg: struct_ver=0x%x checksum=0x%x command=0x%x command_ver=0x%x data_len=0x%x\n",
		out_msg->ec_request.struct_version,
		out_msg->ec_request.checksum,
		out_msg->ec_request.command,
		out_msg->ec_request.command_version,
		out_msg->ec_request.data_len);

	/* Send command to ISH EC firmware and read response */
	rv = ish_send(client_data,
		      (u8 *)out_msg, out_size,
		      (u8 *)in_msg, in_size);
	if (rv < 0)
		goto end_error;

	rv = prepare_cros_ec_rx(ec_dev, in_msg, msg);
	if (rv)
		goto end_error;

	rv = in_msg->ec_response.data_len;

	dev_dbg(dev,
		"in_msg: struct_ver=0x%x checksum=0x%x result=0x%x data_len=0x%x\n",
		in_msg->ec_response.struct_version,
		in_msg->ec_response.checksum,
		in_msg->ec_response.result,
		in_msg->ec_response.data_len);

end_error:
	if (msg->command == EC_CMD_REBOOT_EC)
		msleep(EC_REBOOT_DELAY_MS);

	up_read(&init_lock);

	return rv;
}

static int cros_ec_dev_init(struct ishtp_cl_data *client_data)
{
	struct cros_ec_device *ec_dev;
	struct device *dev = cl_data_to_dev(client_data);

	ec_dev = devm_kzalloc(dev, sizeof(*ec_dev), GFP_KERNEL);
	if (!ec_dev)
		return -ENOMEM;

	client_data->ec_dev = ec_dev;
	dev->driver_data = ec_dev;

	ec_dev->dev = dev;
	ec_dev->priv = client_data->cros_ish_cl;
	ec_dev->cmd_xfer = NULL;
	ec_dev->pkt_xfer = cros_ec_pkt_xfer_ish;
	ec_dev->phys_name = dev_name(dev);
	ec_dev->din_size = sizeof(struct cros_ish_in_msg) +
			   sizeof(struct ec_response_get_protocol_info);
	ec_dev->dout_size = sizeof(struct cros_ish_out_msg);

	return cros_ec_register(ec_dev);
}

static void reset_handler(struct work_struct *work)
{
	int rv;
	struct device *dev;
	struct ishtp_cl *cros_ish_cl;
	struct ishtp_cl_device *cl_device;
	struct ishtp_cl_data *client_data =
		container_of(work, struct ishtp_cl_data, work_ishtp_reset);

	/* Lock for reset to complete */
	down_write(&init_lock);

	cros_ish_cl = client_data->cros_ish_cl;
	cl_device = client_data->cl_device;

	/* Unlink, flush queues & start again */
	ishtp_cl_unlink(cros_ish_cl);
	ishtp_cl_flush_queues(cros_ish_cl);
	ishtp_cl_free(cros_ish_cl);

	cros_ish_cl = ishtp_cl_allocate(cl_device);
	if (!cros_ish_cl) {
		up_write(&init_lock);
		return;
	}

	ishtp_set_drvdata(cl_device, cros_ish_cl);
	ishtp_set_client_data(cros_ish_cl, client_data);
	client_data->cros_ish_cl = cros_ish_cl;

	rv = cros_ish_init(cros_ish_cl);
	if (rv) {
		ishtp_cl_free(cros_ish_cl);
		dev_err(cl_data_to_dev(client_data), "Reset Failed\n");
		up_write(&init_lock);
		return;
	}

	/* Refresh ec_dev device pointers */
	client_data->ec_dev->priv = client_data->cros_ish_cl;
	dev = cl_data_to_dev(client_data);
	dev->driver_data = client_data->ec_dev;

	dev_info(cl_data_to_dev(client_data), "Chrome EC ISH reset done\n");

	up_write(&init_lock);
}

/**
 * cros_ec_ishtp_probe() - ISHTP client driver probe callback
 * @cl_device: ISHTP client device instance
 *
 * Return: 0 for success, negative error code for failure.
 */
static int cros_ec_ishtp_probe(struct ishtp_cl_device *cl_device)
{
	int rv;
	struct ishtp_cl *cros_ish_cl;
	struct ishtp_cl_data *client_data =
		devm_kzalloc(ishtp_device(cl_device),
			     sizeof(*client_data), GFP_KERNEL);
	if (!client_data)
		return -ENOMEM;

	/* Lock for initialization to complete */
	down_write(&init_lock);

	cros_ish_cl = ishtp_cl_allocate(cl_device);
	if (!cros_ish_cl) {
		rv = -ENOMEM;
		goto end_ishtp_cl_alloc_error;
	}

	ishtp_set_drvdata(cl_device, cros_ish_cl);
	ishtp_set_client_data(cros_ish_cl, client_data);
	client_data->cros_ish_cl = cros_ish_cl;
	client_data->cl_device = cl_device;

	init_waitqueue_head(&client_data->response.wait_queue);

	INIT_WORK(&client_data->work_ishtp_reset,
		  reset_handler);
	INIT_WORK(&client_data->work_ec_evt,
		  ish_evt_handler);

	rv = cros_ish_init(cros_ish_cl);
	if (rv)
		goto end_ishtp_cl_init_error;

	ishtp_get_device(cl_device);

	up_write(&init_lock);

	/* Register croc_ec_dev mfd */
	rv = cros_ec_dev_init(client_data);
	if (rv)
		goto end_cros_ec_dev_init_error;

	return 0;

end_cros_ec_dev_init_error:
	ishtp_set_connection_state(cros_ish_cl, ISHTP_CL_DISCONNECTING);
	ishtp_cl_disconnect(cros_ish_cl);
	ishtp_cl_unlink(cros_ish_cl);
	ishtp_cl_flush_queues(cros_ish_cl);
	ishtp_put_device(cl_device);
end_ishtp_cl_init_error:
	ishtp_cl_free(cros_ish_cl);
end_ishtp_cl_alloc_error:
	up_write(&init_lock);
	return rv;
}

/**
 * cros_ec_ishtp_remove() - ISHTP client driver remove callback
 * @cl_device: ISHTP client device instance
 *
 * Return: 0
 */
static int cros_ec_ishtp_remove(struct ishtp_cl_device *cl_device)
{
	struct ishtp_cl	*cros_ish_cl = ishtp_get_drvdata(cl_device);
	struct ishtp_cl_data *client_data = ishtp_get_client_data(cros_ish_cl);

	cancel_work_sync(&client_data->work_ishtp_reset);
	cancel_work_sync(&client_data->work_ec_evt);
	cros_ish_deinit(cros_ish_cl);
	ishtp_put_device(cl_device);

	return 0;
}

/**
 * cros_ec_ishtp_reset() - ISHTP client driver reset callback
 * @cl_device: ISHTP client device instance
 *
 * Return: 0
 */
static int cros_ec_ishtp_reset(struct ishtp_cl_device *cl_device)
{
	struct ishtp_cl	*cros_ish_cl = ishtp_get_drvdata(cl_device);
	struct ishtp_cl_data *client_data = ishtp_get_client_data(cros_ish_cl);

	schedule_work(&client_data->work_ishtp_reset);

	return 0;
}

/**
 * cros_ec_ishtp_suspend() - ISHTP client driver suspend callback
 * @device: device instance
 *
 * Return: 0 for success, negative error code for failure.
 */
static int __maybe_unused cros_ec_ishtp_suspend(struct device *device)
{
	struct ishtp_cl_device *cl_device = ishtp_dev_to_cl_device(device);
	struct ishtp_cl	*cros_ish_cl = ishtp_get_drvdata(cl_device);
	struct ishtp_cl_data *client_data = ishtp_get_client_data(cros_ish_cl);

	return cros_ec_suspend(client_data->ec_dev);
}

/**
 * cros_ec_ishtp_resume() - ISHTP client driver resume callback
 * @device: device instance
 *
 * Return: 0 for success, negative error code for failure.
 */
static int __maybe_unused cros_ec_ishtp_resume(struct device *device)
{
	struct ishtp_cl_device *cl_device = ishtp_dev_to_cl_device(device);
	struct ishtp_cl	*cros_ish_cl = ishtp_get_drvdata(cl_device);
	struct ishtp_cl_data *client_data = ishtp_get_client_data(cros_ish_cl);

	return cros_ec_resume(client_data->ec_dev);
}

static SIMPLE_DEV_PM_OPS(cros_ec_ishtp_pm_ops, cros_ec_ishtp_suspend,
			 cros_ec_ishtp_resume);

static struct ishtp_cl_driver	cros_ec_ishtp_driver = {
	.name = "cros_ec_ishtp",
	.guid = &cros_ish_guid,
	.probe = cros_ec_ishtp_probe,
	.remove = cros_ec_ishtp_remove,
	.reset = cros_ec_ishtp_reset,
	.driver = {
		.pm = &cros_ec_ishtp_pm_ops,
	},
};

static int __init cros_ec_ishtp_mod_init(void)
{
	return ishtp_cl_driver_register(&cros_ec_ishtp_driver, THIS_MODULE);
}

static void __exit cros_ec_ishtp_mod_exit(void)
{
	ishtp_cl_driver_unregister(&cros_ec_ishtp_driver);
}

module_init(cros_ec_ishtp_mod_init);
module_exit(cros_ec_ishtp_mod_exit);

MODULE_DESCRIPTION("ChromeOS EC ISHTP Client Driver");
MODULE_AUTHOR("Rushikesh S Kadam <rushikesh.s.kadam@intel.com>");

MODULE_LICENSE("GPL v2");
MODULE_ALIAS("ishtp:*");