1// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
   2// Copyright(c) 2015-17 Intel Corporation.
   3
   4#include <linux/acpi.h>
   5#include <linux/delay.h>
   6#include <linux/mod_devicetable.h>
   7#include <linux/pm_runtime.h>
   8#include <linux/soundwire/sdw_registers.h>
   9#include <linux/soundwire/sdw.h>
  10#include <linux/soundwire/sdw_type.h>
  11#include "bus.h"
  12#include "irq.h"
  13#include "sysfs_local.h"
  14
  15static DEFINE_IDA(sdw_bus_ida);
  16
  17static int sdw_get_id(struct sdw_bus *bus)
  18{
  19	int rc = ida_alloc(&sdw_bus_ida, GFP_KERNEL);
  20
  21	if (rc < 0)
  22		return rc;
  23
  24	bus->id = rc;
  25
  26	if (bus->controller_id == -1)
  27		bus->controller_id = rc;
  28
  29	return 0;
  30}
  31
  32/**
  33 * sdw_bus_master_add() - add a bus Master instance
  34 * @bus: bus instance
  35 * @parent: parent device
  36 * @fwnode: firmware node handle
  37 *
  38 * Initializes the bus instance, read properties and create child
  39 * devices.
  40 */
  41int sdw_bus_master_add(struct sdw_bus *bus, struct device *parent,
  42		       struct fwnode_handle *fwnode)
  43{
  44	struct sdw_master_prop *prop = NULL;
  45	int ret;
  46
  47	if (!parent) {
  48		pr_err("SoundWire parent device is not set\n");
  49		return -ENODEV;
  50	}
  51
  52	ret = sdw_get_id(bus);
  53	if (ret < 0) {
  54		dev_err(parent, "Failed to get bus id\n");
  55		return ret;
  56	}
  57
  58	ret = sdw_master_device_add(bus, parent, fwnode);
  59	if (ret < 0) {
  60		dev_err(parent, "Failed to add master device at link %d\n",
  61			bus->link_id);
  62		return ret;
  63	}
  64
  65	if (!bus->ops) {
  66		dev_err(bus->dev, "SoundWire Bus ops are not set\n");
  67		return -EINVAL;
  68	}
  69
  70	if (!bus->compute_params) {
  71		dev_err(bus->dev,
  72			"Bandwidth allocation not configured, compute_params no set\n");
  73		return -EINVAL;
  74	}
  75
  76	/*
  77	 * Give each bus_lock and msg_lock a unique key so that lockdep won't
  78	 * trigger a deadlock warning when the locks of several buses are
  79	 * grabbed during configuration of a multi-bus stream.
  80	 */
  81	lockdep_register_key(&bus->msg_lock_key);
  82	__mutex_init(&bus->msg_lock, "msg_lock", &bus->msg_lock_key);
  83
  84	lockdep_register_key(&bus->bus_lock_key);
  85	__mutex_init(&bus->bus_lock, "bus_lock", &bus->bus_lock_key);
  86
  87	INIT_LIST_HEAD(&bus->slaves);
  88	INIT_LIST_HEAD(&bus->m_rt_list);
  89
  90	/*
  91	 * Initialize multi_link flag
  92	 */
  93	bus->multi_link = false;
  94	if (bus->ops->read_prop) {
  95		ret = bus->ops->read_prop(bus);
  96		if (ret < 0) {
  97			dev_err(bus->dev,
  98				"Bus read properties failed:%d\n", ret);
  99			return ret;
 100		}
 101	}
 102
 103	sdw_bus_debugfs_init(bus);
 104
 105	/*
 106	 * Device numbers in SoundWire are 0 through 15. Enumeration device
 107	 * number (0), Broadcast device number (15), Group numbers (12 and
 108	 * 13) and Master device number (14) are not used for assignment so
 109	 * mask these and other higher bits.
 110	 */
 111
 112	/* Set higher order bits */
 113	*bus->assigned = ~GENMASK(SDW_BROADCAST_DEV_NUM, SDW_ENUM_DEV_NUM);
 114
 115	/* Set enumuration device number and broadcast device number */
 116	set_bit(SDW_ENUM_DEV_NUM, bus->assigned);
 117	set_bit(SDW_BROADCAST_DEV_NUM, bus->assigned);
 118
 119	/* Set group device numbers and master device number */
 120	set_bit(SDW_GROUP12_DEV_NUM, bus->assigned);
 121	set_bit(SDW_GROUP13_DEV_NUM, bus->assigned);
 122	set_bit(SDW_MASTER_DEV_NUM, bus->assigned);
 123
 124	/*
 125	 * SDW is an enumerable bus, but devices can be powered off. So,
 126	 * they won't be able to report as present.
 127	 *
 128	 * Create Slave devices based on Slaves described in
 129	 * the respective firmware (ACPI/DT)
 130	 */
 131	if (IS_ENABLED(CONFIG_ACPI) && ACPI_HANDLE(bus->dev))
 132		ret = sdw_acpi_find_slaves(bus);
 133	else if (IS_ENABLED(CONFIG_OF) && bus->dev->of_node)
 134		ret = sdw_of_find_slaves(bus);
 135	else
 136		ret = -ENOTSUPP; /* No ACPI/DT so error out */
 137
 138	if (ret < 0) {
 139		dev_err(bus->dev, "Finding slaves failed:%d\n", ret);
 140		return ret;
 141	}
 142
 143	/*
 144	 * Initialize clock values based on Master properties. The max
 145	 * frequency is read from max_clk_freq property. Current assumption
 146	 * is that the bus will start at highest clock frequency when
 147	 * powered on.
 148	 *
 149	 * Default active bank will be 0 as out of reset the Slaves have
 150	 * to start with bank 0 (Table 40 of Spec)
 151	 */
 152	prop = &bus->prop;
 153	bus->params.max_dr_freq = prop->max_clk_freq * SDW_DOUBLE_RATE_FACTOR;
 154	bus->params.curr_dr_freq = bus->params.max_dr_freq;
 155	bus->params.curr_bank = SDW_BANK0;
 156	bus->params.next_bank = SDW_BANK1;
 157
 158	ret = sdw_irq_create(bus, fwnode);
 159	if (ret)
 160		return ret;
 161
 162	return 0;
 163}
 164EXPORT_SYMBOL(sdw_bus_master_add);
 165
 166static int sdw_delete_slave(struct device *dev, void *data)
 167{
 168	struct sdw_slave *slave = dev_to_sdw_dev(dev);
 169	struct sdw_bus *bus = slave->bus;
 170
 171	pm_runtime_disable(dev);
 172
 173	sdw_slave_debugfs_exit(slave);
 174
 175	mutex_lock(&bus->bus_lock);
 176
 177	if (slave->dev_num) { /* clear dev_num if assigned */
 178		clear_bit(slave->dev_num, bus->assigned);
 179		if (bus->ops && bus->ops->put_device_num)
 180			bus->ops->put_device_num(bus, slave);
 181	}
 182	list_del_init(&slave->node);
 183	mutex_unlock(&bus->bus_lock);
 184
 185	device_unregister(dev);
 186	return 0;
 187}
 188
 189/**
 190 * sdw_bus_master_delete() - delete the bus master instance
 191 * @bus: bus to be deleted
 192 *
 193 * Remove the instance, delete the child devices.
 194 */
 195void sdw_bus_master_delete(struct sdw_bus *bus)
 196{
 197	device_for_each_child(bus->dev, NULL, sdw_delete_slave);
 198
 199	sdw_irq_delete(bus);
 200
 201	sdw_master_device_del(bus);
 202
 203	sdw_bus_debugfs_exit(bus);
 204	lockdep_unregister_key(&bus->bus_lock_key);
 205	lockdep_unregister_key(&bus->msg_lock_key);
 206	ida_free(&sdw_bus_ida, bus->id);
 207}
 208EXPORT_SYMBOL(sdw_bus_master_delete);
 209
 210/*
 211 * SDW IO Calls
 212 */
 213
 214static inline int find_response_code(enum sdw_command_response resp)
 215{
 216	switch (resp) {
 217	case SDW_CMD_OK:
 218		return 0;
 219
 220	case SDW_CMD_IGNORED:
 221		return -ENODATA;
 222
 223	case SDW_CMD_TIMEOUT:
 224		return -ETIMEDOUT;
 225
 226	default:
 227		return -EIO;
 228	}
 229}
 230
 231static inline int do_transfer(struct sdw_bus *bus, struct sdw_msg *msg)
 232{
 233	int retry = bus->prop.err_threshold;
 234	enum sdw_command_response resp;
 235	int ret = 0, i;
 236
 237	for (i = 0; i <= retry; i++) {
 238		resp = bus->ops->xfer_msg(bus, msg);
 239		ret = find_response_code(resp);
 240
 241		/* if cmd is ok or ignored return */
 242		if (ret == 0 || ret == -ENODATA)
 243			return ret;
 244	}
 245
 246	return ret;
 247}
 248
 249static inline int do_transfer_defer(struct sdw_bus *bus,
 250				    struct sdw_msg *msg)
 251{
 252	struct sdw_defer *defer = &bus->defer_msg;
 253	int retry = bus->prop.err_threshold;
 254	enum sdw_command_response resp;
 255	int ret = 0, i;
 256
 257	defer->msg = msg;
 258	defer->length = msg->len;
 259	init_completion(&defer->complete);
 260
 261	for (i = 0; i <= retry; i++) {
 262		resp = bus->ops->xfer_msg_defer(bus);
 263		ret = find_response_code(resp);
 264		/* if cmd is ok or ignored return */
 265		if (ret == 0 || ret == -ENODATA)
 266			return ret;
 267	}
 268
 269	return ret;
 270}
 271
 272static int sdw_transfer_unlocked(struct sdw_bus *bus, struct sdw_msg *msg)
 273{
 274	int ret;
 275
 276	ret = do_transfer(bus, msg);
 277	if (ret != 0 && ret != -ENODATA)
 278		dev_err(bus->dev, "trf on Slave %d failed:%d %s addr %x count %d\n",
 279			msg->dev_num, ret,
 280			(msg->flags & SDW_MSG_FLAG_WRITE) ? "write" : "read",
 281			msg->addr, msg->len);
 282
 283	return ret;
 284}
 285
 286/**
 287 * sdw_transfer() - Synchronous transfer message to a SDW Slave device
 288 * @bus: SDW bus
 289 * @msg: SDW message to be xfered
 290 */
 291int sdw_transfer(struct sdw_bus *bus, struct sdw_msg *msg)
 292{
 293	int ret;
 294
 295	mutex_lock(&bus->msg_lock);
 296
 297	ret = sdw_transfer_unlocked(bus, msg);
 298
 299	mutex_unlock(&bus->msg_lock);
 300
 301	return ret;
 302}
 303
 304/**
 305 * sdw_show_ping_status() - Direct report of PING status, to be used by Peripheral drivers
 306 * @bus: SDW bus
 307 * @sync_delay: Delay before reading status
 308 */
 309void sdw_show_ping_status(struct sdw_bus *bus, bool sync_delay)
 310{
 311	u32 status;
 312
 313	if (!bus->ops->read_ping_status)
 314		return;
 315
 316	/*
 317	 * wait for peripheral to sync if desired. 10-15ms should be more than
 318	 * enough in most cases.
 319	 */
 320	if (sync_delay)
 321		usleep_range(10000, 15000);
 322
 323	mutex_lock(&bus->msg_lock);
 324
 325	status = bus->ops->read_ping_status(bus);
 326
 327	mutex_unlock(&bus->msg_lock);
 328
 329	if (!status)
 330		dev_warn(bus->dev, "%s: no peripherals attached\n", __func__);
 331	else
 332		dev_dbg(bus->dev, "PING status: %#x\n", status);
 333}
 334EXPORT_SYMBOL(sdw_show_ping_status);
 335
 336/**
 337 * sdw_transfer_defer() - Asynchronously transfer message to a SDW Slave device
 338 * @bus: SDW bus
 339 * @msg: SDW message to be xfered
 340 *
 341 * Caller needs to hold the msg_lock lock while calling this
 342 */
 343int sdw_transfer_defer(struct sdw_bus *bus, struct sdw_msg *msg)
 344{
 345	int ret;
 346
 347	if (!bus->ops->xfer_msg_defer)
 348		return -ENOTSUPP;
 349
 350	ret = do_transfer_defer(bus, msg);
 351	if (ret != 0 && ret != -ENODATA)
 352		dev_err(bus->dev, "Defer trf on Slave %d failed:%d\n",
 353			msg->dev_num, ret);
 354
 355	return ret;
 356}
 357
 358int sdw_fill_msg(struct sdw_msg *msg, struct sdw_slave *slave,
 359		 u32 addr, size_t count, u16 dev_num, u8 flags, u8 *buf)
 360{
 361	memset(msg, 0, sizeof(*msg));
 362	msg->addr = addr; /* addr is 16 bit and truncated here */
 363	msg->len = count;
 364	msg->dev_num = dev_num;
 365	msg->flags = flags;
 366	msg->buf = buf;
 367
 368	if (addr < SDW_REG_NO_PAGE) /* no paging area */
 369		return 0;
 370
 371	if (addr >= SDW_REG_MAX) { /* illegal addr */
 372		pr_err("SDW: Invalid address %x passed\n", addr);
 373		return -EINVAL;
 374	}
 375
 376	if (addr < SDW_REG_OPTIONAL_PAGE) { /* 32k but no page */
 377		if (slave && !slave->prop.paging_support)
 378			return 0;
 379		/* no need for else as that will fall-through to paging */
 380	}
 381
 382	/* paging mandatory */
 383	if (dev_num == SDW_ENUM_DEV_NUM || dev_num == SDW_BROADCAST_DEV_NUM) {
 384		pr_err("SDW: Invalid device for paging :%d\n", dev_num);
 385		return -EINVAL;
 386	}
 387
 388	if (!slave) {
 389		pr_err("SDW: No slave for paging addr\n");
 390		return -EINVAL;
 391	}
 392
 393	if (!slave->prop.paging_support) {
 394		dev_err(&slave->dev,
 395			"address %x needs paging but no support\n", addr);
 396		return -EINVAL;
 397	}
 398
 399	msg->addr_page1 = FIELD_GET(SDW_SCP_ADDRPAGE1_MASK, addr);
 400	msg->addr_page2 = FIELD_GET(SDW_SCP_ADDRPAGE2_MASK, addr);
 401	msg->addr |= BIT(15);
 402	msg->page = true;
 403
 404	return 0;
 405}
 406
 407/*
 408 * Read/Write IO functions.
 409 */
 410
 411static int sdw_ntransfer_no_pm(struct sdw_slave *slave, u32 addr, u8 flags,
 412			       size_t count, u8 *val)
 413{
 414	struct sdw_msg msg;
 415	size_t size;
 416	int ret;
 417
 418	while (count) {
 419		// Only handle bytes up to next page boundary
 420		size = min_t(size_t, count, (SDW_REGADDR + 1) - (addr & SDW_REGADDR));
 421
 422		ret = sdw_fill_msg(&msg, slave, addr, size, slave->dev_num, flags, val);
 423		if (ret < 0)
 424			return ret;
 425
 426		ret = sdw_transfer(slave->bus, &msg);
 427		if (ret < 0 && !slave->is_mockup_device)
 428			return ret;
 429
 430		addr += size;
 431		val += size;
 432		count -= size;
 433	}
 434
 435	return 0;
 436}
 437
 438/**
 439 * sdw_nread_no_pm() - Read "n" contiguous SDW Slave registers with no PM
 440 * @slave: SDW Slave
 441 * @addr: Register address
 442 * @count: length
 443 * @val: Buffer for values to be read
 444 *
 445 * Note that if the message crosses a page boundary each page will be
 446 * transferred under a separate invocation of the msg_lock.
 447 */
 448int sdw_nread_no_pm(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
 449{
 450	return sdw_ntransfer_no_pm(slave, addr, SDW_MSG_FLAG_READ, count, val);
 451}
 452EXPORT_SYMBOL(sdw_nread_no_pm);
 453
 454/**
 455 * sdw_nwrite_no_pm() - Write "n" contiguous SDW Slave registers with no PM
 456 * @slave: SDW Slave
 457 * @addr: Register address
 458 * @count: length
 459 * @val: Buffer for values to be written
 460 *
 461 * Note that if the message crosses a page boundary each page will be
 462 * transferred under a separate invocation of the msg_lock.
 463 */
 464int sdw_nwrite_no_pm(struct sdw_slave *slave, u32 addr, size_t count, const u8 *val)
 465{
 466	return sdw_ntransfer_no_pm(slave, addr, SDW_MSG_FLAG_WRITE, count, (u8 *)val);
 467}
 468EXPORT_SYMBOL(sdw_nwrite_no_pm);
 469
 470/**
 471 * sdw_write_no_pm() - Write a SDW Slave register with no PM
 472 * @slave: SDW Slave
 473 * @addr: Register address
 474 * @value: Register value
 475 */
 476int sdw_write_no_pm(struct sdw_slave *slave, u32 addr, u8 value)
 477{
 478	return sdw_nwrite_no_pm(slave, addr, 1, &value);
 479}
 480EXPORT_SYMBOL(sdw_write_no_pm);
 481
 482static int
 483sdw_bread_no_pm(struct sdw_bus *bus, u16 dev_num, u32 addr)
 484{
 485	struct sdw_msg msg;
 486	u8 buf;
 487	int ret;
 488
 489	ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 490			   SDW_MSG_FLAG_READ, &buf);
 491	if (ret < 0)
 492		return ret;
 493
 494	ret = sdw_transfer(bus, &msg);
 495	if (ret < 0)
 496		return ret;
 497
 498	return buf;
 499}
 500
 501static int
 502sdw_bwrite_no_pm(struct sdw_bus *bus, u16 dev_num, u32 addr, u8 value)
 503{
 504	struct sdw_msg msg;
 505	int ret;
 506
 507	ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 508			   SDW_MSG_FLAG_WRITE, &value);
 509	if (ret < 0)
 510		return ret;
 511
 512	return sdw_transfer(bus, &msg);
 513}
 514
 515int sdw_bread_no_pm_unlocked(struct sdw_bus *bus, u16 dev_num, u32 addr)
 516{
 517	struct sdw_msg msg;
 518	u8 buf;
 519	int ret;
 520
 521	ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 522			   SDW_MSG_FLAG_READ, &buf);
 523	if (ret < 0)
 524		return ret;
 525
 526	ret = sdw_transfer_unlocked(bus, &msg);
 527	if (ret < 0)
 528		return ret;
 529
 530	return buf;
 531}
 532EXPORT_SYMBOL(sdw_bread_no_pm_unlocked);
 533
 534int sdw_bwrite_no_pm_unlocked(struct sdw_bus *bus, u16 dev_num, u32 addr, u8 value)
 535{
 536	struct sdw_msg msg;
 537	int ret;
 538
 539	ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 540			   SDW_MSG_FLAG_WRITE, &value);
 541	if (ret < 0)
 542		return ret;
 543
 544	return sdw_transfer_unlocked(bus, &msg);
 545}
 546EXPORT_SYMBOL(sdw_bwrite_no_pm_unlocked);
 547
 548/**
 549 * sdw_read_no_pm() - Read a SDW Slave register with no PM
 550 * @slave: SDW Slave
 551 * @addr: Register address
 552 */
 553int sdw_read_no_pm(struct sdw_slave *slave, u32 addr)
 554{
 555	u8 buf;
 556	int ret;
 557
 558	ret = sdw_nread_no_pm(slave, addr, 1, &buf);
 559	if (ret < 0)
 560		return ret;
 561	else
 562		return buf;
 563}
 564EXPORT_SYMBOL(sdw_read_no_pm);
 565
 566int sdw_update_no_pm(struct sdw_slave *slave, u32 addr, u8 mask, u8 val)
 567{
 568	int tmp;
 569
 570	tmp = sdw_read_no_pm(slave, addr);
 571	if (tmp < 0)
 572		return tmp;
 573
 574	tmp = (tmp & ~mask) | val;
 575	return sdw_write_no_pm(slave, addr, tmp);
 576}
 577EXPORT_SYMBOL(sdw_update_no_pm);
 578
 579/* Read-Modify-Write Slave register */
 580int sdw_update(struct sdw_slave *slave, u32 addr, u8 mask, u8 val)
 581{
 582	int tmp;
 583
 584	tmp = sdw_read(slave, addr);
 585	if (tmp < 0)
 586		return tmp;
 587
 588	tmp = (tmp & ~mask) | val;
 589	return sdw_write(slave, addr, tmp);
 590}
 591EXPORT_SYMBOL(sdw_update);
 592
 593/**
 594 * sdw_nread() - Read "n" contiguous SDW Slave registers
 595 * @slave: SDW Slave
 596 * @addr: Register address
 597 * @count: length
 598 * @val: Buffer for values to be read
 599 *
 600 * This version of the function will take a PM reference to the slave
 601 * device.
 602 * Note that if the message crosses a page boundary each page will be
 603 * transferred under a separate invocation of the msg_lock.
 604 */
 605int sdw_nread(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
 606{
 607	int ret;
 608
 609	ret = pm_runtime_get_sync(&slave->dev);
 610	if (ret < 0 && ret != -EACCES) {
 611		pm_runtime_put_noidle(&slave->dev);
 612		return ret;
 613	}
 614
 615	ret = sdw_nread_no_pm(slave, addr, count, val);
 616
 617	pm_runtime_mark_last_busy(&slave->dev);
 618	pm_runtime_put(&slave->dev);
 619
 620	return ret;
 621}
 622EXPORT_SYMBOL(sdw_nread);
 623
 624/**
 625 * sdw_nwrite() - Write "n" contiguous SDW Slave registers
 626 * @slave: SDW Slave
 627 * @addr: Register address
 628 * @count: length
 629 * @val: Buffer for values to be written
 630 *
 631 * This version of the function will take a PM reference to the slave
 632 * device.
 633 * Note that if the message crosses a page boundary each page will be
 634 * transferred under a separate invocation of the msg_lock.
 635 */
 636int sdw_nwrite(struct sdw_slave *slave, u32 addr, size_t count, const u8 *val)
 637{
 638	int ret;
 639
 640	ret = pm_runtime_get_sync(&slave->dev);
 641	if (ret < 0 && ret != -EACCES) {
 642		pm_runtime_put_noidle(&slave->dev);
 643		return ret;
 644	}
 645
 646	ret = sdw_nwrite_no_pm(slave, addr, count, val);
 647
 648	pm_runtime_mark_last_busy(&slave->dev);
 649	pm_runtime_put(&slave->dev);
 650
 651	return ret;
 652}
 653EXPORT_SYMBOL(sdw_nwrite);
 654
 655/**
 656 * sdw_read() - Read a SDW Slave register
 657 * @slave: SDW Slave
 658 * @addr: Register address
 659 *
 660 * This version of the function will take a PM reference to the slave
 661 * device.
 662 */
 663int sdw_read(struct sdw_slave *slave, u32 addr)
 664{
 665	u8 buf;
 666	int ret;
 667
 668	ret = sdw_nread(slave, addr, 1, &buf);
 669	if (ret < 0)
 670		return ret;
 671
 672	return buf;
 673}
 674EXPORT_SYMBOL(sdw_read);
 675
 676/**
 677 * sdw_write() - Write a SDW Slave register
 678 * @slave: SDW Slave
 679 * @addr: Register address
 680 * @value: Register value
 681 *
 682 * This version of the function will take a PM reference to the slave
 683 * device.
 684 */
 685int sdw_write(struct sdw_slave *slave, u32 addr, u8 value)
 686{
 687	return sdw_nwrite(slave, addr, 1, &value);
 688}
 689EXPORT_SYMBOL(sdw_write);
 690
 691/*
 692 * SDW alert handling
 693 */
 694
 695/* called with bus_lock held */
 696static struct sdw_slave *sdw_get_slave(struct sdw_bus *bus, int i)
 697{
 698	struct sdw_slave *slave;
 699
 700	list_for_each_entry(slave, &bus->slaves, node) {
 701		if (slave->dev_num == i)
 702			return slave;
 703	}
 704
 705	return NULL;
 706}
 707
 708int sdw_compare_devid(struct sdw_slave *slave, struct sdw_slave_id id)
 709{
 710	if (slave->id.mfg_id != id.mfg_id ||
 711	    slave->id.part_id != id.part_id ||
 712	    slave->id.class_id != id.class_id ||
 713	    (slave->id.unique_id != SDW_IGNORED_UNIQUE_ID &&
 714	     slave->id.unique_id != id.unique_id))
 715		return -ENODEV;
 716
 717	return 0;
 718}
 719EXPORT_SYMBOL(sdw_compare_devid);
 720
 721/* called with bus_lock held */
 722static int sdw_get_device_num(struct sdw_slave *slave)
 723{
 724	struct sdw_bus *bus = slave->bus;
 725	int bit;
 726
 727	if (bus->ops && bus->ops->get_device_num) {
 728		bit = bus->ops->get_device_num(bus, slave);
 729		if (bit < 0)
 730			goto err;
 731	} else {
 732		bit = find_first_zero_bit(bus->assigned, SDW_MAX_DEVICES);
 733		if (bit == SDW_MAX_DEVICES) {
 734			bit = -ENODEV;
 735			goto err;
 736		}
 737	}
 738
 739	/*
 740	 * Do not update dev_num in Slave data structure here,
 741	 * Update once program dev_num is successful
 742	 */
 743	set_bit(bit, bus->assigned);
 744
 745err:
 746	return bit;
 747}
 748
 749static int sdw_assign_device_num(struct sdw_slave *slave)
 750{
 751	struct sdw_bus *bus = slave->bus;
 752	int ret, dev_num;
 753	bool new_device = false;
 754
 755	/* check first if device number is assigned, if so reuse that */
 756	if (!slave->dev_num) {
 757		if (!slave->dev_num_sticky) {
 758			mutex_lock(&slave->bus->bus_lock);
 759			dev_num = sdw_get_device_num(slave);
 760			mutex_unlock(&slave->bus->bus_lock);
 761			if (dev_num < 0) {
 762				dev_err(bus->dev, "Get dev_num failed: %d\n",
 763					dev_num);
 764				return dev_num;
 765			}
 766			slave->dev_num = dev_num;
 767			slave->dev_num_sticky = dev_num;
 768			new_device = true;
 769		} else {
 770			slave->dev_num = slave->dev_num_sticky;
 771		}
 772	}
 773
 774	if (!new_device)
 775		dev_dbg(bus->dev,
 776			"Slave already registered, reusing dev_num:%d\n",
 777			slave->dev_num);
 778
 779	/* Clear the slave->dev_num to transfer message on device 0 */
 780	dev_num = slave->dev_num;
 781	slave->dev_num = 0;
 782
 783	ret = sdw_write_no_pm(slave, SDW_SCP_DEVNUMBER, dev_num);
 784	if (ret < 0) {
 785		dev_err(bus->dev, "Program device_num %d failed: %d\n",
 786			dev_num, ret);
 787		return ret;
 788	}
 789
 790	/* After xfer of msg, restore dev_num */
 791	slave->dev_num = slave->dev_num_sticky;
 792
 793	if (bus->ops && bus->ops->new_peripheral_assigned)
 794		bus->ops->new_peripheral_assigned(bus, slave, dev_num);
 795
 796	return 0;
 797}
 798
 799void sdw_extract_slave_id(struct sdw_bus *bus,
 800			  u64 addr, struct sdw_slave_id *id)
 801{
 802	dev_dbg(bus->dev, "SDW Slave Addr: %llx\n", addr);
 803
 804	id->sdw_version = SDW_VERSION(addr);
 805	id->unique_id = SDW_UNIQUE_ID(addr);
 806	id->mfg_id = SDW_MFG_ID(addr);
 807	id->part_id = SDW_PART_ID(addr);
 808	id->class_id = SDW_CLASS_ID(addr);
 809
 810	dev_dbg(bus->dev,
 811		"SDW Slave class_id 0x%02x, mfg_id 0x%04x, part_id 0x%04x, unique_id 0x%x, version 0x%x\n",
 812		id->class_id, id->mfg_id, id->part_id, id->unique_id, id->sdw_version);
 813}
 814EXPORT_SYMBOL(sdw_extract_slave_id);
 815
 816static int sdw_program_device_num(struct sdw_bus *bus, bool *programmed)
 817{
 818	u8 buf[SDW_NUM_DEV_ID_REGISTERS] = {0};
 819	struct sdw_slave *slave, *_s;
 820	struct sdw_slave_id id;
 821	struct sdw_msg msg;
 822	bool found;
 823	int count = 0, ret;
 824	u64 addr;
 825
 826	*programmed = false;
 827
 828	/* No Slave, so use raw xfer api */
 829	ret = sdw_fill_msg(&msg, NULL, SDW_SCP_DEVID_0,
 830			   SDW_NUM_DEV_ID_REGISTERS, 0, SDW_MSG_FLAG_READ, buf);
 831	if (ret < 0)
 832		return ret;
 833
 834	do {
 835		ret = sdw_transfer(bus, &msg);
 836		if (ret == -ENODATA) { /* end of device id reads */
 837			dev_dbg(bus->dev, "No more devices to enumerate\n");
 838			ret = 0;
 839			break;
 840		}
 841		if (ret < 0) {
 842			dev_err(bus->dev, "DEVID read fail:%d\n", ret);
 843			break;
 844		}
 845
 846		/*
 847		 * Construct the addr and extract. Cast the higher shift
 848		 * bits to avoid truncation due to size limit.
 849		 */
 850		addr = buf[5] | (buf[4] << 8) | (buf[3] << 16) |
 851			((u64)buf[2] << 24) | ((u64)buf[1] << 32) |
 852			((u64)buf[0] << 40);
 853
 854		sdw_extract_slave_id(bus, addr, &id);
 855
 856		found = false;
 857		/* Now compare with entries */
 858		list_for_each_entry_safe(slave, _s, &bus->slaves, node) {
 859			if (sdw_compare_devid(slave, id) == 0) {
 860				found = true;
 861
 862				/*
 863				 * To prevent skipping state-machine stages don't
 864				 * program a device until we've seen it UNATTACH.
 865				 * Must return here because no other device on #0
 866				 * can be detected until this one has been
 867				 * assigned a device ID.
 868				 */
 869				if (slave->status != SDW_SLAVE_UNATTACHED)
 870					return 0;
 871
 872				/*
 873				 * Assign a new dev_num to this Slave and
 874				 * not mark it present. It will be marked
 875				 * present after it reports ATTACHED on new
 876				 * dev_num
 877				 */
 878				ret = sdw_assign_device_num(slave);
 879				if (ret < 0) {
 880					dev_err(bus->dev,
 881						"Assign dev_num failed:%d\n",
 882						ret);
 883					return ret;
 884				}
 885
 886				*programmed = true;
 887
 888				break;
 889			}
 890		}
 891
 892		if (!found) {
 893			/* TODO: Park this device in Group 13 */
 894
 895			/*
 896			 * add Slave device even if there is no platform
 897			 * firmware description. There will be no driver probe
 898			 * but the user/integration will be able to see the
 899			 * device, enumeration status and device number in sysfs
 900			 */
 901			sdw_slave_add(bus, &id, NULL);
 902
 903			dev_err(bus->dev, "Slave Entry not found\n");
 904		}
 905
 906		count++;
 907
 908		/*
 909		 * Check till error out or retry (count) exhausts.
 910		 * Device can drop off and rejoin during enumeration
 911		 * so count till twice the bound.
 912		 */
 913
 914	} while (ret == 0 && count < (SDW_MAX_DEVICES * 2));
 915
 916	return ret;
 917}
 918
 919static void sdw_modify_slave_status(struct sdw_slave *slave,
 920				    enum sdw_slave_status status)
 921{
 922	struct sdw_bus *bus = slave->bus;
 923
 924	mutex_lock(&bus->bus_lock);
 925
 926	dev_vdbg(bus->dev,
 927		 "changing status slave %d status %d new status %d\n",
 928		 slave->dev_num, slave->status, status);
 929
 930	if (status == SDW_SLAVE_UNATTACHED) {
 931		dev_dbg(&slave->dev,
 932			"initializing enumeration and init completion for Slave %d\n",
 933			slave->dev_num);
 934
 935		reinit_completion(&slave->enumeration_complete);
 936		reinit_completion(&slave->initialization_complete);
 937
 938	} else if ((status == SDW_SLAVE_ATTACHED) &&
 939		   (slave->status == SDW_SLAVE_UNATTACHED)) {
 940		dev_dbg(&slave->dev,
 941			"signaling enumeration completion for Slave %d\n",
 942			slave->dev_num);
 943
 944		complete_all(&slave->enumeration_complete);
 945	}
 946	slave->status = status;
 947	mutex_unlock(&bus->bus_lock);
 948}
 949
 950static int sdw_slave_clk_stop_callback(struct sdw_slave *slave,
 951				       enum sdw_clk_stop_mode mode,
 952				       enum sdw_clk_stop_type type)
 953{
 954	int ret = 0;
 955
 956	mutex_lock(&slave->sdw_dev_lock);
 957
 958	if (slave->probed)  {
 959		struct device *dev = &slave->dev;
 960		struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
 961
 962		if (drv->ops && drv->ops->clk_stop)
 963			ret = drv->ops->clk_stop(slave, mode, type);
 964	}
 965
 966	mutex_unlock(&slave->sdw_dev_lock);
 967
 968	return ret;
 969}
 970
 971static int sdw_slave_clk_stop_prepare(struct sdw_slave *slave,
 972				      enum sdw_clk_stop_mode mode,
 973				      bool prepare)
 974{
 975	bool wake_en;
 976	u32 val = 0;
 977	int ret;
 978
 979	wake_en = slave->prop.wake_capable;
 980
 981	if (prepare) {
 982		val = SDW_SCP_SYSTEMCTRL_CLK_STP_PREP;
 983
 984		if (mode == SDW_CLK_STOP_MODE1)
 985			val |= SDW_SCP_SYSTEMCTRL_CLK_STP_MODE1;
 986
 987		if (wake_en)
 988			val |= SDW_SCP_SYSTEMCTRL_WAKE_UP_EN;
 989	} else {
 990		ret = sdw_read_no_pm(slave, SDW_SCP_SYSTEMCTRL);
 991		if (ret < 0) {
 992			if (ret != -ENODATA)
 993				dev_err(&slave->dev, "SDW_SCP_SYSTEMCTRL read failed:%d\n", ret);
 994			return ret;
 995		}
 996		val = ret;
 997		val &= ~(SDW_SCP_SYSTEMCTRL_CLK_STP_PREP);
 998	}
 999
1000	ret = sdw_write_no_pm(slave, SDW_SCP_SYSTEMCTRL, val);
1001
1002	if (ret < 0 && ret != -ENODATA)
1003		dev_err(&slave->dev, "SDW_SCP_SYSTEMCTRL write failed:%d\n", ret);
1004
1005	return ret;
1006}
1007
1008static int sdw_bus_wait_for_clk_prep_deprep(struct sdw_bus *bus, u16 dev_num, bool prepare)
1009{
1010	int retry = bus->clk_stop_timeout;
1011	int val;
1012
1013	do {
1014		val = sdw_bread_no_pm(bus, dev_num, SDW_SCP_STAT);
1015		if (val < 0) {
1016			if (val != -ENODATA)
1017				dev_err(bus->dev, "SDW_SCP_STAT bread failed:%d\n", val);
1018			return val;
1019		}
1020		val &= SDW_SCP_STAT_CLK_STP_NF;
1021		if (!val) {
1022			dev_dbg(bus->dev, "clock stop %s done slave:%d\n",
1023				prepare ? "prepare" : "deprepare",
1024				dev_num);
1025			return 0;
1026		}
1027
1028		usleep_range(1000, 1500);
1029		retry--;
1030	} while (retry);
1031
1032	dev_dbg(bus->dev, "clock stop %s did not complete for slave:%d\n",
1033		prepare ? "prepare" : "deprepare",
1034		dev_num);
1035
1036	return -ETIMEDOUT;
1037}
1038
1039/**
1040 * sdw_bus_prep_clk_stop: prepare Slave(s) for clock stop
1041 *
1042 * @bus: SDW bus instance
1043 *
1044 * Query Slave for clock stop mode and prepare for that mode.
1045 */
1046int sdw_bus_prep_clk_stop(struct sdw_bus *bus)
1047{
1048	bool simple_clk_stop = true;
1049	struct sdw_slave *slave;
1050	bool is_slave = false;
1051	int ret = 0;
1052
1053	/*
1054	 * In order to save on transition time, prepare
1055	 * each Slave and then wait for all Slave(s) to be
1056	 * prepared for clock stop.
1057	 * If one of the Slave devices has lost sync and
1058	 * replies with Command Ignored/-ENODATA, we continue
1059	 * the loop
1060	 */
1061	list_for_each_entry(slave, &bus->slaves, node) {
1062		if (!slave->dev_num)
1063			continue;
1064
1065		if (slave->status != SDW_SLAVE_ATTACHED &&
1066		    slave->status != SDW_SLAVE_ALERT)
1067			continue;
1068
1069		/* Identify if Slave(s) are available on Bus */
1070		is_slave = true;
1071
1072		ret = sdw_slave_clk_stop_callback(slave,
1073						  SDW_CLK_STOP_MODE0,
1074						  SDW_CLK_PRE_PREPARE);
1075		if (ret < 0 && ret != -ENODATA) {
1076			dev_err(&slave->dev, "clock stop pre-prepare cb failed:%d\n", ret);
1077			return ret;
1078		}
1079
1080		/* Only prepare a Slave device if needed */
1081		if (!slave->prop.simple_clk_stop_capable) {
1082			simple_clk_stop = false;
1083
1084			ret = sdw_slave_clk_stop_prepare(slave,
1085							 SDW_CLK_STOP_MODE0,
1086							 true);
1087			if (ret < 0 && ret != -ENODATA) {
1088				dev_err(&slave->dev, "clock stop prepare failed:%d\n", ret);
1089				return ret;
1090			}
1091		}
1092	}
1093
1094	/* Skip remaining clock stop preparation if no Slave is attached */
1095	if (!is_slave)
1096		return 0;
1097
1098	/*
1099	 * Don't wait for all Slaves to be ready if they follow the simple
1100	 * state machine
1101	 */
1102	if (!simple_clk_stop) {
1103		ret = sdw_bus_wait_for_clk_prep_deprep(bus,
1104						       SDW_BROADCAST_DEV_NUM, true);
1105		/*
1106		 * if there are no Slave devices present and the reply is
1107		 * Command_Ignored/-ENODATA, we don't need to continue with the
1108		 * flow and can just return here. The error code is not modified
1109		 * and its handling left as an exercise for the caller.
1110		 */
1111		if (ret < 0)
1112			return ret;
1113	}
1114
1115	/* Inform slaves that prep is done */
1116	list_for_each_entry(slave, &bus->slaves, node) {
1117		if (!slave->dev_num)
1118			continue;
1119
1120		if (slave->status != SDW_SLAVE_ATTACHED &&
1121		    slave->status != SDW_SLAVE_ALERT)
1122			continue;
1123
1124		ret = sdw_slave_clk_stop_callback(slave,
1125						  SDW_CLK_STOP_MODE0,
1126						  SDW_CLK_POST_PREPARE);
1127
1128		if (ret < 0 && ret != -ENODATA) {
1129			dev_err(&slave->dev, "clock stop post-prepare cb failed:%d\n", ret);
1130			return ret;
1131		}
1132	}
1133
1134	return 0;
1135}
1136EXPORT_SYMBOL(sdw_bus_prep_clk_stop);
1137
1138/**
1139 * sdw_bus_clk_stop: stop bus clock
1140 *
1141 * @bus: SDW bus instance
1142 *
1143 * After preparing the Slaves for clock stop, stop the clock by broadcasting
1144 * write to SCP_CTRL register.
1145 */
1146int sdw_bus_clk_stop(struct sdw_bus *bus)
1147{
1148	int ret;
1149
1150	/*
1151	 * broadcast clock stop now, attached Slaves will ACK this,
1152	 * unattached will ignore
1153	 */
1154	ret = sdw_bwrite_no_pm(bus, SDW_BROADCAST_DEV_NUM,
1155			       SDW_SCP_CTRL, SDW_SCP_CTRL_CLK_STP_NOW);
1156	if (ret < 0) {
1157		if (ret != -ENODATA)
1158			dev_err(bus->dev, "ClockStopNow Broadcast msg failed %d\n", ret);
1159		return ret;
1160	}
1161
1162	return 0;
1163}
1164EXPORT_SYMBOL(sdw_bus_clk_stop);
1165
1166/**
1167 * sdw_bus_exit_clk_stop: Exit clock stop mode
1168 *
1169 * @bus: SDW bus instance
1170 *
1171 * This De-prepares the Slaves by exiting Clock Stop Mode 0. For the Slaves
1172 * exiting Clock Stop Mode 1, they will be de-prepared after they enumerate
1173 * back.
1174 */
1175int sdw_bus_exit_clk_stop(struct sdw_bus *bus)
1176{
1177	bool simple_clk_stop = true;
1178	struct sdw_slave *slave;
1179	bool is_slave = false;
1180	int ret;
1181
1182	/*
1183	 * In order to save on transition time, de-prepare
1184	 * each Slave and then wait for all Slave(s) to be
1185	 * de-prepared after clock resume.
1186	 */
1187	list_for_each_entry(slave, &bus->slaves, node) {
1188		if (!slave->dev_num)
1189			continue;
1190
1191		if (slave->status != SDW_SLAVE_ATTACHED &&
1192		    slave->status != SDW_SLAVE_ALERT)
1193			continue;
1194
1195		/* Identify if Slave(s) are available on Bus */
1196		is_slave = true;
1197
1198		ret = sdw_slave_clk_stop_callback(slave, SDW_CLK_STOP_MODE0,
1199						  SDW_CLK_PRE_DEPREPARE);
1200		if (ret < 0)
1201			dev_warn(&slave->dev, "clock stop pre-deprepare cb failed:%d\n", ret);
1202
1203		/* Only de-prepare a Slave device if needed */
1204		if (!slave->prop.simple_clk_stop_capable) {
1205			simple_clk_stop = false;
1206
1207			ret = sdw_slave_clk_stop_prepare(slave, SDW_CLK_STOP_MODE0,
1208							 false);
1209
1210			if (ret < 0)
1211				dev_warn(&slave->dev, "clock stop deprepare failed:%d\n", ret);
1212		}
1213	}
1214
1215	/* Skip remaining clock stop de-preparation if no Slave is attached */
1216	if (!is_slave)
1217		return 0;
1218
1219	/*
1220	 * Don't wait for all Slaves to be ready if they follow the simple
1221	 * state machine
1222	 */
1223	if (!simple_clk_stop) {
1224		ret = sdw_bus_wait_for_clk_prep_deprep(bus, SDW_BROADCAST_DEV_NUM, false);
1225		if (ret < 0)
1226			dev_warn(bus->dev, "clock stop deprepare wait failed:%d\n", ret);
1227	}
1228
1229	list_for_each_entry(slave, &bus->slaves, node) {
1230		if (!slave->dev_num)
1231			continue;
1232
1233		if (slave->status != SDW_SLAVE_ATTACHED &&
1234		    slave->status != SDW_SLAVE_ALERT)
1235			continue;
1236
1237		ret = sdw_slave_clk_stop_callback(slave, SDW_CLK_STOP_MODE0,
1238						  SDW_CLK_POST_DEPREPARE);
1239		if (ret < 0)
1240			dev_warn(&slave->dev, "clock stop post-deprepare cb failed:%d\n", ret);
1241	}
1242
1243	return 0;
1244}
1245EXPORT_SYMBOL(sdw_bus_exit_clk_stop);
1246
1247int sdw_configure_dpn_intr(struct sdw_slave *slave,
1248			   int port, bool enable, int mask)
1249{
1250	u32 addr;
1251	int ret;
1252	u8 val = 0;
1253
1254	if (slave->bus->params.s_data_mode != SDW_PORT_DATA_MODE_NORMAL) {
1255		dev_dbg(&slave->dev, "TEST FAIL interrupt %s\n",
1256			enable ? "on" : "off");
1257		mask |= SDW_DPN_INT_TEST_FAIL;
1258	}
1259
1260	addr = SDW_DPN_INTMASK(port);
1261
1262	/* Set/Clear port ready interrupt mask */
1263	if (enable) {
1264		val |= mask;
1265		val |= SDW_DPN_INT_PORT_READY;
1266	} else {
1267		val &= ~(mask);
1268		val &= ~SDW_DPN_INT_PORT_READY;
1269	}
1270
1271	ret = sdw_update_no_pm(slave, addr, (mask | SDW_DPN_INT_PORT_READY), val);
1272	if (ret < 0)
1273		dev_err(&slave->dev,
1274			"SDW_DPN_INTMASK write failed:%d\n", val);
1275
1276	return ret;
1277}
1278
1279static int sdw_slave_set_frequency(struct sdw_slave *slave)
1280{
1281	u32 mclk_freq = slave->bus->prop.mclk_freq;
1282	u32 curr_freq = slave->bus->params.curr_dr_freq >> 1;
1283	unsigned int scale;
1284	u8 scale_index;
1285	u8 base;
1286	int ret;
1287
1288	/*
1289	 * frequency base and scale registers are required for SDCA
1290	 * devices. They may also be used for 1.2+/non-SDCA devices.
1291	 * Driver can set the property, we will need a DisCo property
1292	 * to discover this case from platform firmware.
1293	 */
1294	if (!slave->id.class_id && !slave->prop.clock_reg_supported)
1295		return 0;
1296
1297	if (!mclk_freq) {
1298		dev_err(&slave->dev,
1299			"no bus MCLK, cannot set SDW_SCP_BUS_CLOCK_BASE\n");
1300		return -EINVAL;
1301	}
1302
1303	/*
1304	 * map base frequency using Table 89 of SoundWire 1.2 spec.
1305	 * The order of the tests just follows the specification, this
1306	 * is not a selection between possible values or a search for
1307	 * the best value but just a mapping.  Only one case per platform
1308	 * is relevant.
1309	 * Some BIOS have inconsistent values for mclk_freq but a
1310	 * correct root so we force the mclk_freq to avoid variations.
1311	 */
1312	if (!(19200000 % mclk_freq)) {
1313		mclk_freq = 19200000;
1314		base = SDW_SCP_BASE_CLOCK_19200000_HZ;
1315	} else if (!(24000000 % mclk_freq)) {
1316		mclk_freq = 24000000;
1317		base = SDW_SCP_BASE_CLOCK_24000000_HZ;
1318	} else if (!(24576000 % mclk_freq)) {
1319		mclk_freq = 24576000;
1320		base = SDW_SCP_BASE_CLOCK_24576000_HZ;
1321	} else if (!(22579200 % mclk_freq)) {
1322		mclk_freq = 22579200;
1323		base = SDW_SCP_BASE_CLOCK_22579200_HZ;
 
 
 
1324	} else if (!(32000000 % mclk_freq)) {
1325		mclk_freq = 32000000;
1326		base = SDW_SCP_BASE_CLOCK_32000000_HZ;
 
 
 
1327	} else {
1328		dev_err(&slave->dev,
1329			"Unsupported clock base, mclk %d\n",
1330			mclk_freq);
1331		return -EINVAL;
1332	}
1333
1334	if (mclk_freq % curr_freq) {
1335		dev_err(&slave->dev,
1336			"mclk %d is not multiple of bus curr_freq %d\n",
1337			mclk_freq, curr_freq);
1338		return -EINVAL;
1339	}
1340
1341	scale = mclk_freq / curr_freq;
1342
1343	/*
1344	 * map scale to Table 90 of SoundWire 1.2 spec - and check
1345	 * that the scale is a power of two and maximum 64
1346	 */
1347	scale_index = ilog2(scale);
1348
1349	if (BIT(scale_index) != scale || scale_index > 6) {
1350		dev_err(&slave->dev,
1351			"No match found for scale %d, bus mclk %d curr_freq %d\n",
1352			scale, mclk_freq, curr_freq);
1353		return -EINVAL;
1354	}
1355	scale_index++;
1356
1357	ret = sdw_write_no_pm(slave, SDW_SCP_BUS_CLOCK_BASE, base);
1358	if (ret < 0) {
1359		dev_err(&slave->dev,
1360			"SDW_SCP_BUS_CLOCK_BASE write failed:%d\n", ret);
1361		return ret;
1362	}
1363
1364	/* initialize scale for both banks */
1365	ret = sdw_write_no_pm(slave, SDW_SCP_BUSCLOCK_SCALE_B0, scale_index);
1366	if (ret < 0) {
1367		dev_err(&slave->dev,
1368			"SDW_SCP_BUSCLOCK_SCALE_B0 write failed:%d\n", ret);
1369		return ret;
1370	}
1371	ret = sdw_write_no_pm(slave, SDW_SCP_BUSCLOCK_SCALE_B1, scale_index);
1372	if (ret < 0)
1373		dev_err(&slave->dev,
1374			"SDW_SCP_BUSCLOCK_SCALE_B1 write failed:%d\n", ret);
1375
1376	dev_dbg(&slave->dev,
1377		"Configured bus base %d, scale %d, mclk %d, curr_freq %d\n",
1378		base, scale_index, mclk_freq, curr_freq);
1379
1380	return ret;
1381}
1382
1383static int sdw_initialize_slave(struct sdw_slave *slave)
1384{
1385	struct sdw_slave_prop *prop = &slave->prop;
1386	int status;
1387	int ret;
1388	u8 val;
1389
1390	ret = sdw_slave_set_frequency(slave);
1391	if (ret < 0)
1392		return ret;
1393
1394	if (slave->bus->prop.quirks & SDW_MASTER_QUIRKS_CLEAR_INITIAL_CLASH) {
1395		/* Clear bus clash interrupt before enabling interrupt mask */
1396		status = sdw_read_no_pm(slave, SDW_SCP_INT1);
1397		if (status < 0) {
1398			dev_err(&slave->dev,
1399				"SDW_SCP_INT1 (BUS_CLASH) read failed:%d\n", status);
1400			return status;
1401		}
1402		if (status & SDW_SCP_INT1_BUS_CLASH) {
1403			dev_warn(&slave->dev, "Bus clash detected before INT mask is enabled\n");
1404			ret = sdw_write_no_pm(slave, SDW_SCP_INT1, SDW_SCP_INT1_BUS_CLASH);
1405			if (ret < 0) {
1406				dev_err(&slave->dev,
1407					"SDW_SCP_INT1 (BUS_CLASH) write failed:%d\n", ret);
1408				return ret;
1409			}
1410		}
1411	}
1412	if ((slave->bus->prop.quirks & SDW_MASTER_QUIRKS_CLEAR_INITIAL_PARITY) &&
1413	    !(slave->prop.quirks & SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY)) {
1414		/* Clear parity interrupt before enabling interrupt mask */
1415		status = sdw_read_no_pm(slave, SDW_SCP_INT1);
1416		if (status < 0) {
1417			dev_err(&slave->dev,
1418				"SDW_SCP_INT1 (PARITY) read failed:%d\n", status);
1419			return status;
1420		}
1421		if (status & SDW_SCP_INT1_PARITY) {
1422			dev_warn(&slave->dev, "PARITY error detected before INT mask is enabled\n");
1423			ret = sdw_write_no_pm(slave, SDW_SCP_INT1, SDW_SCP_INT1_PARITY);
1424			if (ret < 0) {
1425				dev_err(&slave->dev,
1426					"SDW_SCP_INT1 (PARITY) write failed:%d\n", ret);
1427				return ret;
1428			}
1429		}
1430	}
1431
1432	/*
1433	 * Set SCP_INT1_MASK register, typically bus clash and
1434	 * implementation-defined interrupt mask. The Parity detection
1435	 * may not always be correct on startup so its use is
1436	 * device-dependent, it might e.g. only be enabled in
1437	 * steady-state after a couple of frames.
1438	 */
1439	val = slave->prop.scp_int1_mask;
1440
1441	/* Enable SCP interrupts */
1442	ret = sdw_update_no_pm(slave, SDW_SCP_INTMASK1, val, val);
1443	if (ret < 0) {
1444		dev_err(&slave->dev,
1445			"SDW_SCP_INTMASK1 write failed:%d\n", ret);
1446		return ret;
1447	}
1448
1449	/* No need to continue if DP0 is not present */
1450	if (!slave->prop.dp0_prop)
1451		return 0;
1452
1453	/* Enable DP0 interrupts */
1454	val = prop->dp0_prop->imp_def_interrupts;
1455	val |= SDW_DP0_INT_PORT_READY | SDW_DP0_INT_BRA_FAILURE;
1456
1457	ret = sdw_update_no_pm(slave, SDW_DP0_INTMASK, val, val);
1458	if (ret < 0)
1459		dev_err(&slave->dev,
1460			"SDW_DP0_INTMASK read failed:%d\n", ret);
1461	return ret;
1462}
1463
1464static int sdw_handle_dp0_interrupt(struct sdw_slave *slave, u8 *slave_status)
1465{
1466	u8 clear, impl_int_mask;
1467	int status, status2, ret, count = 0;
1468
1469	status = sdw_read_no_pm(slave, SDW_DP0_INT);
1470	if (status < 0) {
1471		dev_err(&slave->dev,
1472			"SDW_DP0_INT read failed:%d\n", status);
1473		return status;
1474	}
1475
1476	do {
1477		clear = status & ~SDW_DP0_INTERRUPTS;
1478
1479		if (status & SDW_DP0_INT_TEST_FAIL) {
1480			dev_err(&slave->dev, "Test fail for port 0\n");
1481			clear |= SDW_DP0_INT_TEST_FAIL;
1482		}
1483
1484		/*
1485		 * Assumption: PORT_READY interrupt will be received only for
1486		 * ports implementing Channel Prepare state machine (CP_SM)
1487		 */
1488
1489		if (status & SDW_DP0_INT_PORT_READY) {
1490			complete(&slave->port_ready[0]);
1491			clear |= SDW_DP0_INT_PORT_READY;
1492		}
1493
1494		if (status & SDW_DP0_INT_BRA_FAILURE) {
1495			dev_err(&slave->dev, "BRA failed\n");
1496			clear |= SDW_DP0_INT_BRA_FAILURE;
1497		}
1498
1499		impl_int_mask = SDW_DP0_INT_IMPDEF1 |
1500			SDW_DP0_INT_IMPDEF2 | SDW_DP0_INT_IMPDEF3;
1501
1502		if (status & impl_int_mask) {
1503			clear |= impl_int_mask;
1504			*slave_status = clear;
1505		}
1506
1507		/* clear the interrupts but don't touch reserved and SDCA_CASCADE fields */
1508		ret = sdw_write_no_pm(slave, SDW_DP0_INT, clear);
1509		if (ret < 0) {
1510			dev_err(&slave->dev,
1511				"SDW_DP0_INT write failed:%d\n", ret);
1512			return ret;
1513		}
1514
1515		/* Read DP0 interrupt again */
1516		status2 = sdw_read_no_pm(slave, SDW_DP0_INT);
1517		if (status2 < 0) {
1518			dev_err(&slave->dev,
1519				"SDW_DP0_INT read failed:%d\n", status2);
1520			return status2;
1521		}
1522		/* filter to limit loop to interrupts identified in the first status read */
1523		status &= status2;
1524
1525		count++;
1526
1527		/* we can get alerts while processing so keep retrying */
1528	} while ((status & SDW_DP0_INTERRUPTS) && (count < SDW_READ_INTR_CLEAR_RETRY));
1529
1530	if (count == SDW_READ_INTR_CLEAR_RETRY)
1531		dev_warn(&slave->dev, "Reached MAX_RETRY on DP0 read\n");
1532
1533	return ret;
1534}
1535
1536static int sdw_handle_port_interrupt(struct sdw_slave *slave,
1537				     int port, u8 *slave_status)
1538{
1539	u8 clear, impl_int_mask;
1540	int status, status2, ret, count = 0;
1541	u32 addr;
1542
1543	if (port == 0)
1544		return sdw_handle_dp0_interrupt(slave, slave_status);
1545
1546	addr = SDW_DPN_INT(port);
1547	status = sdw_read_no_pm(slave, addr);
1548	if (status < 0) {
1549		dev_err(&slave->dev,
1550			"SDW_DPN_INT read failed:%d\n", status);
1551
1552		return status;
1553	}
1554
1555	do {
1556		clear = status & ~SDW_DPN_INTERRUPTS;
1557
1558		if (status & SDW_DPN_INT_TEST_FAIL) {
1559			dev_err(&slave->dev, "Test fail for port:%d\n", port);
1560			clear |= SDW_DPN_INT_TEST_FAIL;
1561		}
1562
1563		/*
1564		 * Assumption: PORT_READY interrupt will be received only
1565		 * for ports implementing CP_SM.
1566		 */
1567		if (status & SDW_DPN_INT_PORT_READY) {
1568			complete(&slave->port_ready[port]);
1569			clear |= SDW_DPN_INT_PORT_READY;
1570		}
1571
1572		impl_int_mask = SDW_DPN_INT_IMPDEF1 |
1573			SDW_DPN_INT_IMPDEF2 | SDW_DPN_INT_IMPDEF3;
1574
1575		if (status & impl_int_mask) {
1576			clear |= impl_int_mask;
1577			*slave_status = clear;
1578		}
1579
1580		/* clear the interrupt but don't touch reserved fields */
1581		ret = sdw_write_no_pm(slave, addr, clear);
1582		if (ret < 0) {
1583			dev_err(&slave->dev,
1584				"SDW_DPN_INT write failed:%d\n", ret);
1585			return ret;
1586		}
1587
1588		/* Read DPN interrupt again */
1589		status2 = sdw_read_no_pm(slave, addr);
1590		if (status2 < 0) {
1591			dev_err(&slave->dev,
1592				"SDW_DPN_INT read failed:%d\n", status2);
1593			return status2;
1594		}
1595		/* filter to limit loop to interrupts identified in the first status read */
1596		status &= status2;
1597
1598		count++;
1599
1600		/* we can get alerts while processing so keep retrying */
1601	} while ((status & SDW_DPN_INTERRUPTS) && (count < SDW_READ_INTR_CLEAR_RETRY));
1602
1603	if (count == SDW_READ_INTR_CLEAR_RETRY)
1604		dev_warn(&slave->dev, "Reached MAX_RETRY on port read");
1605
1606	return ret;
1607}
1608
1609static int sdw_handle_slave_alerts(struct sdw_slave *slave)
1610{
1611	struct sdw_slave_intr_status slave_intr;
1612	u8 clear = 0, bit, port_status[15] = {0};
1613	int port_num, stat, ret, count = 0;
1614	unsigned long port;
1615	bool slave_notify;
1616	u8 sdca_cascade = 0;
1617	u8 buf, buf2[2];
1618	bool parity_check;
1619	bool parity_quirk;
1620
1621	sdw_modify_slave_status(slave, SDW_SLAVE_ALERT);
1622
1623	ret = pm_runtime_get_sync(&slave->dev);
1624	if (ret < 0 && ret != -EACCES) {
1625		dev_err(&slave->dev, "Failed to resume device: %d\n", ret);
1626		pm_runtime_put_noidle(&slave->dev);
1627		return ret;
1628	}
1629
1630	/* Read Intstat 1, Intstat 2 and Intstat 3 registers */
1631	ret = sdw_read_no_pm(slave, SDW_SCP_INT1);
1632	if (ret < 0) {
1633		dev_err(&slave->dev,
1634			"SDW_SCP_INT1 read failed:%d\n", ret);
1635		goto io_err;
1636	}
1637	buf = ret;
1638
1639	ret = sdw_nread_no_pm(slave, SDW_SCP_INTSTAT2, 2, buf2);
1640	if (ret < 0) {
1641		dev_err(&slave->dev,
1642			"SDW_SCP_INT2/3 read failed:%d\n", ret);
1643		goto io_err;
1644	}
1645
1646	if (slave->id.class_id) {
1647		ret = sdw_read_no_pm(slave, SDW_DP0_INT);
1648		if (ret < 0) {
1649			dev_err(&slave->dev,
1650				"SDW_DP0_INT read failed:%d\n", ret);
1651			goto io_err;
1652		}
1653		sdca_cascade = ret & SDW_DP0_SDCA_CASCADE;
1654	}
1655
1656	do {
1657		slave_notify = false;
1658
1659		/*
1660		 * Check parity, bus clash and Slave (impl defined)
1661		 * interrupt
1662		 */
1663		if (buf & SDW_SCP_INT1_PARITY) {
1664			parity_check = slave->prop.scp_int1_mask & SDW_SCP_INT1_PARITY;
1665			parity_quirk = !slave->first_interrupt_done &&
1666				(slave->prop.quirks & SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY);
1667
1668			if (parity_check && !parity_quirk)
1669				dev_err(&slave->dev, "Parity error detected\n");
1670			clear |= SDW_SCP_INT1_PARITY;
1671		}
1672
1673		if (buf & SDW_SCP_INT1_BUS_CLASH) {
1674			if (slave->prop.scp_int1_mask & SDW_SCP_INT1_BUS_CLASH)
1675				dev_err(&slave->dev, "Bus clash detected\n");
1676			clear |= SDW_SCP_INT1_BUS_CLASH;
1677		}
1678
1679		/*
1680		 * When bus clash or parity errors are detected, such errors
1681		 * are unlikely to be recoverable errors.
1682		 * TODO: In such scenario, reset bus. Make this configurable
1683		 * via sysfs property with bus reset being the default.
1684		 */
1685
1686		if (buf & SDW_SCP_INT1_IMPL_DEF) {
1687			if (slave->prop.scp_int1_mask & SDW_SCP_INT1_IMPL_DEF) {
1688				dev_dbg(&slave->dev, "Slave impl defined interrupt\n");
1689				slave_notify = true;
1690			}
1691			clear |= SDW_SCP_INT1_IMPL_DEF;
1692		}
1693
1694		/* the SDCA interrupts are cleared in the codec driver .interrupt_callback() */
1695		if (sdca_cascade)
1696			slave_notify = true;
1697
1698		/* Check port 0 - 3 interrupts */
1699		port = buf & SDW_SCP_INT1_PORT0_3;
1700
1701		/* To get port number corresponding to bits, shift it */
1702		port = FIELD_GET(SDW_SCP_INT1_PORT0_3, port);
1703		for_each_set_bit(bit, &port, 8) {
1704			sdw_handle_port_interrupt(slave, bit,
1705						  &port_status[bit]);
1706		}
1707
1708		/* Check if cascade 2 interrupt is present */
1709		if (buf & SDW_SCP_INT1_SCP2_CASCADE) {
1710			port = buf2[0] & SDW_SCP_INTSTAT2_PORT4_10;
1711			for_each_set_bit(bit, &port, 8) {
1712				/* scp2 ports start from 4 */
1713				port_num = bit + 4;
1714				sdw_handle_port_interrupt(slave,
1715						port_num,
1716						&port_status[port_num]);
1717			}
1718		}
1719
1720		/* now check last cascade */
1721		if (buf2[0] & SDW_SCP_INTSTAT2_SCP3_CASCADE) {
1722			port = buf2[1] & SDW_SCP_INTSTAT3_PORT11_14;
1723			for_each_set_bit(bit, &port, 8) {
1724				/* scp3 ports start from 11 */
1725				port_num = bit + 11;
1726				sdw_handle_port_interrupt(slave,
1727						port_num,
1728						&port_status[port_num]);
1729			}
1730		}
1731
1732		/* Update the Slave driver */
1733		if (slave_notify) {
1734			mutex_lock(&slave->sdw_dev_lock);
1735
1736			if (slave->probed) {
1737				struct device *dev = &slave->dev;
1738				struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
1739
1740				if (slave->prop.use_domain_irq && slave->irq)
1741					handle_nested_irq(slave->irq);
1742
1743				if (drv->ops && drv->ops->interrupt_callback) {
1744					slave_intr.sdca_cascade = sdca_cascade;
1745					slave_intr.control_port = clear;
1746					memcpy(slave_intr.port, &port_status,
1747					       sizeof(slave_intr.port));
1748
1749					drv->ops->interrupt_callback(slave, &slave_intr);
1750				}
1751			}
1752
1753			mutex_unlock(&slave->sdw_dev_lock);
1754		}
1755
1756		/* Ack interrupt */
1757		ret = sdw_write_no_pm(slave, SDW_SCP_INT1, clear);
1758		if (ret < 0) {
1759			dev_err(&slave->dev,
1760				"SDW_SCP_INT1 write failed:%d\n", ret);
1761			goto io_err;
1762		}
1763
1764		/* at this point all initial interrupt sources were handled */
1765		slave->first_interrupt_done = true;
1766
1767		/*
1768		 * Read status again to ensure no new interrupts arrived
1769		 * while servicing interrupts.
1770		 */
1771		ret = sdw_read_no_pm(slave, SDW_SCP_INT1);
1772		if (ret < 0) {
1773			dev_err(&slave->dev,
1774				"SDW_SCP_INT1 recheck read failed:%d\n", ret);
1775			goto io_err;
1776		}
1777		buf = ret;
1778
1779		ret = sdw_nread_no_pm(slave, SDW_SCP_INTSTAT2, 2, buf2);
1780		if (ret < 0) {
1781			dev_err(&slave->dev,
1782				"SDW_SCP_INT2/3 recheck read failed:%d\n", ret);
1783			goto io_err;
1784		}
1785
1786		if (slave->id.class_id) {
1787			ret = sdw_read_no_pm(slave, SDW_DP0_INT);
1788			if (ret < 0) {
1789				dev_err(&slave->dev,
1790					"SDW_DP0_INT recheck read failed:%d\n", ret);
1791				goto io_err;
1792			}
1793			sdca_cascade = ret & SDW_DP0_SDCA_CASCADE;
1794		}
1795
1796		/*
1797		 * Make sure no interrupts are pending
1798		 */
1799		stat = buf || buf2[0] || buf2[1] || sdca_cascade;
1800
1801		/*
1802		 * Exit loop if Slave is continuously in ALERT state even
1803		 * after servicing the interrupt multiple times.
1804		 */
1805		count++;
1806
1807		/* we can get alerts while processing so keep retrying */
1808	} while (stat != 0 && count < SDW_READ_INTR_CLEAR_RETRY);
1809
1810	if (count == SDW_READ_INTR_CLEAR_RETRY)
1811		dev_warn(&slave->dev, "Reached MAX_RETRY on alert read\n");
1812
1813io_err:
1814	pm_runtime_mark_last_busy(&slave->dev);
1815	pm_runtime_put_autosuspend(&slave->dev);
1816
1817	return ret;
1818}
1819
1820static int sdw_update_slave_status(struct sdw_slave *slave,
1821				   enum sdw_slave_status status)
1822{
1823	int ret = 0;
1824
1825	mutex_lock(&slave->sdw_dev_lock);
1826
1827	if (slave->probed) {
1828		struct device *dev = &slave->dev;
1829		struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
1830
1831		if (drv->ops && drv->ops->update_status)
1832			ret = drv->ops->update_status(slave, status);
1833	}
1834
1835	mutex_unlock(&slave->sdw_dev_lock);
1836
1837	return ret;
1838}
1839
1840/**
1841 * sdw_handle_slave_status() - Handle Slave status
1842 * @bus: SDW bus instance
1843 * @status: Status for all Slave(s)
1844 */
1845int sdw_handle_slave_status(struct sdw_bus *bus,
1846			    enum sdw_slave_status status[])
1847{
1848	enum sdw_slave_status prev_status;
1849	struct sdw_slave *slave;
1850	bool attached_initializing, id_programmed;
1851	int i, ret = 0;
1852
1853	/* first check if any Slaves fell off the bus */
1854	for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1855		mutex_lock(&bus->bus_lock);
1856		if (test_bit(i, bus->assigned) == false) {
1857			mutex_unlock(&bus->bus_lock);
1858			continue;
1859		}
1860		mutex_unlock(&bus->bus_lock);
1861
1862		slave = sdw_get_slave(bus, i);
1863		if (!slave)
1864			continue;
1865
1866		if (status[i] == SDW_SLAVE_UNATTACHED &&
1867		    slave->status != SDW_SLAVE_UNATTACHED) {
1868			dev_warn(&slave->dev, "Slave %d state check1: UNATTACHED, status was %d\n",
1869				 i, slave->status);
1870			sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
1871
1872			/* Ensure driver knows that peripheral unattached */
1873			ret = sdw_update_slave_status(slave, status[i]);
1874			if (ret < 0)
1875				dev_warn(&slave->dev, "Update Slave status failed:%d\n", ret);
1876		}
1877	}
1878
1879	if (status[0] == SDW_SLAVE_ATTACHED) {
1880		dev_dbg(bus->dev, "Slave attached, programming device number\n");
1881
1882		/*
1883		 * Programming a device number will have side effects,
1884		 * so we deal with other devices at a later time.
1885		 * This relies on those devices reporting ATTACHED, which will
1886		 * trigger another call to this function. This will only
1887		 * happen if at least one device ID was programmed.
1888		 * Error returns from sdw_program_device_num() are currently
1889		 * ignored because there's no useful recovery that can be done.
1890		 * Returning the error here could result in the current status
1891		 * of other devices not being handled, because if no device IDs
1892		 * were programmed there's nothing to guarantee a status change
1893		 * to trigger another call to this function.
1894		 */
1895		sdw_program_device_num(bus, &id_programmed);
1896		if (id_programmed)
1897			return 0;
1898	}
1899
1900	/* Continue to check other slave statuses */
1901	for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1902		mutex_lock(&bus->bus_lock);
1903		if (test_bit(i, bus->assigned) == false) {
1904			mutex_unlock(&bus->bus_lock);
1905			continue;
1906		}
1907		mutex_unlock(&bus->bus_lock);
1908
1909		slave = sdw_get_slave(bus, i);
1910		if (!slave)
1911			continue;
1912
1913		attached_initializing = false;
1914
1915		switch (status[i]) {
1916		case SDW_SLAVE_UNATTACHED:
1917			if (slave->status == SDW_SLAVE_UNATTACHED)
1918				break;
1919
1920			dev_warn(&slave->dev, "Slave %d state check2: UNATTACHED, status was %d\n",
1921				 i, slave->status);
1922
1923			sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
1924			break;
1925
1926		case SDW_SLAVE_ALERT:
1927			ret = sdw_handle_slave_alerts(slave);
1928			if (ret < 0)
1929				dev_err(&slave->dev,
1930					"Slave %d alert handling failed: %d\n",
1931					i, ret);
1932			break;
1933
1934		case SDW_SLAVE_ATTACHED:
1935			if (slave->status == SDW_SLAVE_ATTACHED)
1936				break;
1937
1938			prev_status = slave->status;
1939			sdw_modify_slave_status(slave, SDW_SLAVE_ATTACHED);
1940
1941			if (prev_status == SDW_SLAVE_ALERT)
1942				break;
1943
1944			attached_initializing = true;
1945
1946			ret = sdw_initialize_slave(slave);
1947			if (ret < 0)
1948				dev_err(&slave->dev,
1949					"Slave %d initialization failed: %d\n",
1950					i, ret);
1951
1952			break;
1953
1954		default:
1955			dev_err(&slave->dev, "Invalid slave %d status:%d\n",
1956				i, status[i]);
1957			break;
1958		}
1959
1960		ret = sdw_update_slave_status(slave, status[i]);
1961		if (ret < 0)
1962			dev_err(&slave->dev,
1963				"Update Slave status failed:%d\n", ret);
1964		if (attached_initializing) {
1965			dev_dbg(&slave->dev,
1966				"signaling initialization completion for Slave %d\n",
1967				slave->dev_num);
1968
1969			complete_all(&slave->initialization_complete);
1970
1971			/*
1972			 * If the manager became pm_runtime active, the peripherals will be
1973			 * restarted and attach, but their pm_runtime status may remain
1974			 * suspended. If the 'update_slave_status' callback initiates
1975			 * any sort of deferred processing, this processing would not be
1976			 * cancelled on pm_runtime suspend.
1977			 * To avoid such zombie states, we queue a request to resume.
1978			 * This would be a no-op in case the peripheral was being resumed
1979			 * by e.g. the ALSA/ASoC framework.
1980			 */
1981			pm_request_resume(&slave->dev);
1982		}
1983	}
1984
1985	return ret;
1986}
1987EXPORT_SYMBOL(sdw_handle_slave_status);
1988
1989void sdw_clear_slave_status(struct sdw_bus *bus, u32 request)
1990{
1991	struct sdw_slave *slave;
1992	int i;
1993
1994	/* Check all non-zero devices */
1995	for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1996		mutex_lock(&bus->bus_lock);
1997		if (test_bit(i, bus->assigned) == false) {
1998			mutex_unlock(&bus->bus_lock);
1999			continue;
2000		}
2001		mutex_unlock(&bus->bus_lock);
2002
2003		slave = sdw_get_slave(bus, i);
2004		if (!slave)
2005			continue;
2006
2007		if (slave->status != SDW_SLAVE_UNATTACHED) {
2008			sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
2009			slave->first_interrupt_done = false;
2010			sdw_update_slave_status(slave, SDW_SLAVE_UNATTACHED);
2011		}
2012
2013		/* keep track of request, used in pm_runtime resume */
2014		slave->unattach_request = request;
2015	}
2016}
2017EXPORT_SYMBOL(sdw_clear_slave_status);