xref: /linux/drivers/soundwire/bus.c (revision 8e07e0e3964ca4e23ce7b68e2096fe660a888942)
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 
15 static DEFINE_IDA(sdw_bus_ida);
16 
17 static 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 	return 0;
26 }
27 
28 /**
29  * sdw_bus_master_add() - add a bus Master instance
30  * @bus: bus instance
31  * @parent: parent device
32  * @fwnode: firmware node handle
33  *
34  * Initializes the bus instance, read properties and create child
35  * devices.
36  */
37 int sdw_bus_master_add(struct sdw_bus *bus, struct device *parent,
38 		       struct fwnode_handle *fwnode)
39 {
40 	struct sdw_master_prop *prop = NULL;
41 	int ret;
42 
43 	if (!parent) {
44 		pr_err("SoundWire parent device is not set\n");
45 		return -ENODEV;
46 	}
47 
48 	ret = sdw_get_id(bus);
49 	if (ret < 0) {
50 		dev_err(parent, "Failed to get bus id\n");
51 		return ret;
52 	}
53 
54 	ret = sdw_master_device_add(bus, parent, fwnode);
55 	if (ret < 0) {
56 		dev_err(parent, "Failed to add master device at link %d\n",
57 			bus->link_id);
58 		return ret;
59 	}
60 
61 	if (!bus->ops) {
62 		dev_err(bus->dev, "SoundWire Bus ops are not set\n");
63 		return -EINVAL;
64 	}
65 
66 	if (!bus->compute_params) {
67 		dev_err(bus->dev,
68 			"Bandwidth allocation not configured, compute_params no set\n");
69 		return -EINVAL;
70 	}
71 
72 	/*
73 	 * Give each bus_lock and msg_lock a unique key so that lockdep won't
74 	 * trigger a deadlock warning when the locks of several buses are
75 	 * grabbed during configuration of a multi-bus stream.
76 	 */
77 	lockdep_register_key(&bus->msg_lock_key);
78 	__mutex_init(&bus->msg_lock, "msg_lock", &bus->msg_lock_key);
79 
80 	lockdep_register_key(&bus->bus_lock_key);
81 	__mutex_init(&bus->bus_lock, "bus_lock", &bus->bus_lock_key);
82 
83 	INIT_LIST_HEAD(&bus->slaves);
84 	INIT_LIST_HEAD(&bus->m_rt_list);
85 
86 	/*
87 	 * Initialize multi_link flag
88 	 */
89 	bus->multi_link = false;
90 	if (bus->ops->read_prop) {
91 		ret = bus->ops->read_prop(bus);
92 		if (ret < 0) {
93 			dev_err(bus->dev,
94 				"Bus read properties failed:%d\n", ret);
95 			return ret;
96 		}
97 	}
98 
99 	sdw_bus_debugfs_init(bus);
100 
101 	/*
102 	 * Device numbers in SoundWire are 0 through 15. Enumeration device
103 	 * number (0), Broadcast device number (15), Group numbers (12 and
104 	 * 13) and Master device number (14) are not used for assignment so
105 	 * mask these and other higher bits.
106 	 */
107 
108 	/* Set higher order bits */
109 	*bus->assigned = ~GENMASK(SDW_BROADCAST_DEV_NUM, SDW_ENUM_DEV_NUM);
110 
111 	/* Set enumuration device number and broadcast device number */
112 	set_bit(SDW_ENUM_DEV_NUM, bus->assigned);
113 	set_bit(SDW_BROADCAST_DEV_NUM, bus->assigned);
114 
115 	/* Set group device numbers and master device number */
116 	set_bit(SDW_GROUP12_DEV_NUM, bus->assigned);
117 	set_bit(SDW_GROUP13_DEV_NUM, bus->assigned);
118 	set_bit(SDW_MASTER_DEV_NUM, bus->assigned);
119 
120 	/*
121 	 * SDW is an enumerable bus, but devices can be powered off. So,
122 	 * they won't be able to report as present.
123 	 *
124 	 * Create Slave devices based on Slaves described in
125 	 * the respective firmware (ACPI/DT)
126 	 */
127 	if (IS_ENABLED(CONFIG_ACPI) && ACPI_HANDLE(bus->dev))
128 		ret = sdw_acpi_find_slaves(bus);
129 	else if (IS_ENABLED(CONFIG_OF) && bus->dev->of_node)
130 		ret = sdw_of_find_slaves(bus);
131 	else
132 		ret = -ENOTSUPP; /* No ACPI/DT so error out */
133 
134 	if (ret < 0) {
135 		dev_err(bus->dev, "Finding slaves failed:%d\n", ret);
136 		return ret;
137 	}
138 
139 	/*
140 	 * Initialize clock values based on Master properties. The max
141 	 * frequency is read from max_clk_freq property. Current assumption
142 	 * is that the bus will start at highest clock frequency when
143 	 * powered on.
144 	 *
145 	 * Default active bank will be 0 as out of reset the Slaves have
146 	 * to start with bank 0 (Table 40 of Spec)
147 	 */
148 	prop = &bus->prop;
149 	bus->params.max_dr_freq = prop->max_clk_freq * SDW_DOUBLE_RATE_FACTOR;
150 	bus->params.curr_dr_freq = bus->params.max_dr_freq;
151 	bus->params.curr_bank = SDW_BANK0;
152 	bus->params.next_bank = SDW_BANK1;
153 
154 	ret = sdw_irq_create(bus, fwnode);
155 	if (ret)
156 		return ret;
157 
158 	return 0;
159 }
160 EXPORT_SYMBOL(sdw_bus_master_add);
161 
162 static int sdw_delete_slave(struct device *dev, void *data)
163 {
164 	struct sdw_slave *slave = dev_to_sdw_dev(dev);
165 	struct sdw_bus *bus = slave->bus;
166 
167 	pm_runtime_disable(dev);
168 
169 	sdw_slave_debugfs_exit(slave);
170 
171 	mutex_lock(&bus->bus_lock);
172 
173 	if (slave->dev_num) { /* clear dev_num if assigned */
174 		clear_bit(slave->dev_num, bus->assigned);
175 		if (bus->ops && bus->ops->put_device_num)
176 			bus->ops->put_device_num(bus, slave);
177 	}
178 	list_del_init(&slave->node);
179 	mutex_unlock(&bus->bus_lock);
180 
181 	device_unregister(dev);
182 	return 0;
183 }
184 
185 /**
186  * sdw_bus_master_delete() - delete the bus master instance
187  * @bus: bus to be deleted
188  *
189  * Remove the instance, delete the child devices.
190  */
191 void sdw_bus_master_delete(struct sdw_bus *bus)
192 {
193 	device_for_each_child(bus->dev, NULL, sdw_delete_slave);
194 
195 	sdw_irq_delete(bus);
196 
197 	sdw_master_device_del(bus);
198 
199 	sdw_bus_debugfs_exit(bus);
200 	lockdep_unregister_key(&bus->bus_lock_key);
201 	lockdep_unregister_key(&bus->msg_lock_key);
202 	ida_free(&sdw_bus_ida, bus->id);
203 }
204 EXPORT_SYMBOL(sdw_bus_master_delete);
205 
206 /*
207  * SDW IO Calls
208  */
209 
210 static inline int find_response_code(enum sdw_command_response resp)
211 {
212 	switch (resp) {
213 	case SDW_CMD_OK:
214 		return 0;
215 
216 	case SDW_CMD_IGNORED:
217 		return -ENODATA;
218 
219 	case SDW_CMD_TIMEOUT:
220 		return -ETIMEDOUT;
221 
222 	default:
223 		return -EIO;
224 	}
225 }
226 
227 static inline int do_transfer(struct sdw_bus *bus, struct sdw_msg *msg)
228 {
229 	int retry = bus->prop.err_threshold;
230 	enum sdw_command_response resp;
231 	int ret = 0, i;
232 
233 	for (i = 0; i <= retry; i++) {
234 		resp = bus->ops->xfer_msg(bus, msg);
235 		ret = find_response_code(resp);
236 
237 		/* if cmd is ok or ignored return */
238 		if (ret == 0 || ret == -ENODATA)
239 			return ret;
240 	}
241 
242 	return ret;
243 }
244 
245 static inline int do_transfer_defer(struct sdw_bus *bus,
246 				    struct sdw_msg *msg)
247 {
248 	struct sdw_defer *defer = &bus->defer_msg;
249 	int retry = bus->prop.err_threshold;
250 	enum sdw_command_response resp;
251 	int ret = 0, i;
252 
253 	defer->msg = msg;
254 	defer->length = msg->len;
255 	init_completion(&defer->complete);
256 
257 	for (i = 0; i <= retry; i++) {
258 		resp = bus->ops->xfer_msg_defer(bus);
259 		ret = find_response_code(resp);
260 		/* if cmd is ok or ignored return */
261 		if (ret == 0 || ret == -ENODATA)
262 			return ret;
263 	}
264 
265 	return ret;
266 }
267 
268 static int sdw_transfer_unlocked(struct sdw_bus *bus, struct sdw_msg *msg)
269 {
270 	int ret;
271 
272 	ret = do_transfer(bus, msg);
273 	if (ret != 0 && ret != -ENODATA)
274 		dev_err(bus->dev, "trf on Slave %d failed:%d %s addr %x count %d\n",
275 			msg->dev_num, ret,
276 			(msg->flags & SDW_MSG_FLAG_WRITE) ? "write" : "read",
277 			msg->addr, msg->len);
278 
279 	return ret;
280 }
281 
282 /**
283  * sdw_transfer() - Synchronous transfer message to a SDW Slave device
284  * @bus: SDW bus
285  * @msg: SDW message to be xfered
286  */
287 int sdw_transfer(struct sdw_bus *bus, struct sdw_msg *msg)
288 {
289 	int ret;
290 
291 	mutex_lock(&bus->msg_lock);
292 
293 	ret = sdw_transfer_unlocked(bus, msg);
294 
295 	mutex_unlock(&bus->msg_lock);
296 
297 	return ret;
298 }
299 
300 /**
301  * sdw_show_ping_status() - Direct report of PING status, to be used by Peripheral drivers
302  * @bus: SDW bus
303  * @sync_delay: Delay before reading status
304  */
305 void sdw_show_ping_status(struct sdw_bus *bus, bool sync_delay)
306 {
307 	u32 status;
308 
309 	if (!bus->ops->read_ping_status)
310 		return;
311 
312 	/*
313 	 * wait for peripheral to sync if desired. 10-15ms should be more than
314 	 * enough in most cases.
315 	 */
316 	if (sync_delay)
317 		usleep_range(10000, 15000);
318 
319 	mutex_lock(&bus->msg_lock);
320 
321 	status = bus->ops->read_ping_status(bus);
322 
323 	mutex_unlock(&bus->msg_lock);
324 
325 	if (!status)
326 		dev_warn(bus->dev, "%s: no peripherals attached\n", __func__);
327 	else
328 		dev_dbg(bus->dev, "PING status: %#x\n", status);
329 }
330 EXPORT_SYMBOL(sdw_show_ping_status);
331 
332 /**
333  * sdw_transfer_defer() - Asynchronously transfer message to a SDW Slave device
334  * @bus: SDW bus
335  * @msg: SDW message to be xfered
336  *
337  * Caller needs to hold the msg_lock lock while calling this
338  */
339 int sdw_transfer_defer(struct sdw_bus *bus, struct sdw_msg *msg)
340 {
341 	int ret;
342 
343 	if (!bus->ops->xfer_msg_defer)
344 		return -ENOTSUPP;
345 
346 	ret = do_transfer_defer(bus, msg);
347 	if (ret != 0 && ret != -ENODATA)
348 		dev_err(bus->dev, "Defer trf on Slave %d failed:%d\n",
349 			msg->dev_num, ret);
350 
351 	return ret;
352 }
353 
354 int sdw_fill_msg(struct sdw_msg *msg, struct sdw_slave *slave,
355 		 u32 addr, size_t count, u16 dev_num, u8 flags, u8 *buf)
356 {
357 	memset(msg, 0, sizeof(*msg));
358 	msg->addr = addr; /* addr is 16 bit and truncated here */
359 	msg->len = count;
360 	msg->dev_num = dev_num;
361 	msg->flags = flags;
362 	msg->buf = buf;
363 
364 	if (addr < SDW_REG_NO_PAGE) /* no paging area */
365 		return 0;
366 
367 	if (addr >= SDW_REG_MAX) { /* illegal addr */
368 		pr_err("SDW: Invalid address %x passed\n", addr);
369 		return -EINVAL;
370 	}
371 
372 	if (addr < SDW_REG_OPTIONAL_PAGE) { /* 32k but no page */
373 		if (slave && !slave->prop.paging_support)
374 			return 0;
375 		/* no need for else as that will fall-through to paging */
376 	}
377 
378 	/* paging mandatory */
379 	if (dev_num == SDW_ENUM_DEV_NUM || dev_num == SDW_BROADCAST_DEV_NUM) {
380 		pr_err("SDW: Invalid device for paging :%d\n", dev_num);
381 		return -EINVAL;
382 	}
383 
384 	if (!slave) {
385 		pr_err("SDW: No slave for paging addr\n");
386 		return -EINVAL;
387 	}
388 
389 	if (!slave->prop.paging_support) {
390 		dev_err(&slave->dev,
391 			"address %x needs paging but no support\n", addr);
392 		return -EINVAL;
393 	}
394 
395 	msg->addr_page1 = FIELD_GET(SDW_SCP_ADDRPAGE1_MASK, addr);
396 	msg->addr_page2 = FIELD_GET(SDW_SCP_ADDRPAGE2_MASK, addr);
397 	msg->addr |= BIT(15);
398 	msg->page = true;
399 
400 	return 0;
401 }
402 
403 /*
404  * Read/Write IO functions.
405  */
406 
407 static int sdw_ntransfer_no_pm(struct sdw_slave *slave, u32 addr, u8 flags,
408 			       size_t count, u8 *val)
409 {
410 	struct sdw_msg msg;
411 	size_t size;
412 	int ret;
413 
414 	while (count) {
415 		// Only handle bytes up to next page boundary
416 		size = min_t(size_t, count, (SDW_REGADDR + 1) - (addr & SDW_REGADDR));
417 
418 		ret = sdw_fill_msg(&msg, slave, addr, size, slave->dev_num, flags, val);
419 		if (ret < 0)
420 			return ret;
421 
422 		ret = sdw_transfer(slave->bus, &msg);
423 		if (ret < 0 && !slave->is_mockup_device)
424 			return ret;
425 
426 		addr += size;
427 		val += size;
428 		count -= size;
429 	}
430 
431 	return 0;
432 }
433 
434 /**
435  * sdw_nread_no_pm() - Read "n" contiguous SDW Slave registers with no PM
436  * @slave: SDW Slave
437  * @addr: Register address
438  * @count: length
439  * @val: Buffer for values to be read
440  *
441  * Note that if the message crosses a page boundary each page will be
442  * transferred under a separate invocation of the msg_lock.
443  */
444 int sdw_nread_no_pm(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
445 {
446 	return sdw_ntransfer_no_pm(slave, addr, SDW_MSG_FLAG_READ, count, val);
447 }
448 EXPORT_SYMBOL(sdw_nread_no_pm);
449 
450 /**
451  * sdw_nwrite_no_pm() - Write "n" contiguous SDW Slave registers with no PM
452  * @slave: SDW Slave
453  * @addr: Register address
454  * @count: length
455  * @val: Buffer for values to be written
456  *
457  * Note that if the message crosses a page boundary each page will be
458  * transferred under a separate invocation of the msg_lock.
459  */
460 int sdw_nwrite_no_pm(struct sdw_slave *slave, u32 addr, size_t count, const u8 *val)
461 {
462 	return sdw_ntransfer_no_pm(slave, addr, SDW_MSG_FLAG_WRITE, count, (u8 *)val);
463 }
464 EXPORT_SYMBOL(sdw_nwrite_no_pm);
465 
466 /**
467  * sdw_write_no_pm() - Write a SDW Slave register with no PM
468  * @slave: SDW Slave
469  * @addr: Register address
470  * @value: Register value
471  */
472 int sdw_write_no_pm(struct sdw_slave *slave, u32 addr, u8 value)
473 {
474 	return sdw_nwrite_no_pm(slave, addr, 1, &value);
475 }
476 EXPORT_SYMBOL(sdw_write_no_pm);
477 
478 static int
479 sdw_bread_no_pm(struct sdw_bus *bus, u16 dev_num, u32 addr)
480 {
481 	struct sdw_msg msg;
482 	u8 buf;
483 	int ret;
484 
485 	ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
486 			   SDW_MSG_FLAG_READ, &buf);
487 	if (ret < 0)
488 		return ret;
489 
490 	ret = sdw_transfer(bus, &msg);
491 	if (ret < 0)
492 		return ret;
493 
494 	return buf;
495 }
496 
497 static int
498 sdw_bwrite_no_pm(struct sdw_bus *bus, u16 dev_num, u32 addr, u8 value)
499 {
500 	struct sdw_msg msg;
501 	int ret;
502 
503 	ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
504 			   SDW_MSG_FLAG_WRITE, &value);
505 	if (ret < 0)
506 		return ret;
507 
508 	return sdw_transfer(bus, &msg);
509 }
510 
511 int sdw_bread_no_pm_unlocked(struct sdw_bus *bus, u16 dev_num, u32 addr)
512 {
513 	struct sdw_msg msg;
514 	u8 buf;
515 	int ret;
516 
517 	ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
518 			   SDW_MSG_FLAG_READ, &buf);
519 	if (ret < 0)
520 		return ret;
521 
522 	ret = sdw_transfer_unlocked(bus, &msg);
523 	if (ret < 0)
524 		return ret;
525 
526 	return buf;
527 }
528 EXPORT_SYMBOL(sdw_bread_no_pm_unlocked);
529 
530 int sdw_bwrite_no_pm_unlocked(struct sdw_bus *bus, u16 dev_num, u32 addr, u8 value)
531 {
532 	struct sdw_msg msg;
533 	int ret;
534 
535 	ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
536 			   SDW_MSG_FLAG_WRITE, &value);
537 	if (ret < 0)
538 		return ret;
539 
540 	return sdw_transfer_unlocked(bus, &msg);
541 }
542 EXPORT_SYMBOL(sdw_bwrite_no_pm_unlocked);
543 
544 /**
545  * sdw_read_no_pm() - Read a SDW Slave register with no PM
546  * @slave: SDW Slave
547  * @addr: Register address
548  */
549 int sdw_read_no_pm(struct sdw_slave *slave, u32 addr)
550 {
551 	u8 buf;
552 	int ret;
553 
554 	ret = sdw_nread_no_pm(slave, addr, 1, &buf);
555 	if (ret < 0)
556 		return ret;
557 	else
558 		return buf;
559 }
560 EXPORT_SYMBOL(sdw_read_no_pm);
561 
562 int sdw_update_no_pm(struct sdw_slave *slave, u32 addr, u8 mask, u8 val)
563 {
564 	int tmp;
565 
566 	tmp = sdw_read_no_pm(slave, addr);
567 	if (tmp < 0)
568 		return tmp;
569 
570 	tmp = (tmp & ~mask) | val;
571 	return sdw_write_no_pm(slave, addr, tmp);
572 }
573 EXPORT_SYMBOL(sdw_update_no_pm);
574 
575 /* Read-Modify-Write Slave register */
576 int sdw_update(struct sdw_slave *slave, u32 addr, u8 mask, u8 val)
577 {
578 	int tmp;
579 
580 	tmp = sdw_read(slave, addr);
581 	if (tmp < 0)
582 		return tmp;
583 
584 	tmp = (tmp & ~mask) | val;
585 	return sdw_write(slave, addr, tmp);
586 }
587 EXPORT_SYMBOL(sdw_update);
588 
589 /**
590  * sdw_nread() - Read "n" contiguous SDW Slave registers
591  * @slave: SDW Slave
592  * @addr: Register address
593  * @count: length
594  * @val: Buffer for values to be read
595  *
596  * This version of the function will take a PM reference to the slave
597  * device.
598  * Note that if the message crosses a page boundary each page will be
599  * transferred under a separate invocation of the msg_lock.
600  */
601 int sdw_nread(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
602 {
603 	int ret;
604 
605 	ret = pm_runtime_get_sync(&slave->dev);
606 	if (ret < 0 && ret != -EACCES) {
607 		pm_runtime_put_noidle(&slave->dev);
608 		return ret;
609 	}
610 
611 	ret = sdw_nread_no_pm(slave, addr, count, val);
612 
613 	pm_runtime_mark_last_busy(&slave->dev);
614 	pm_runtime_put(&slave->dev);
615 
616 	return ret;
617 }
618 EXPORT_SYMBOL(sdw_nread);
619 
620 /**
621  * sdw_nwrite() - Write "n" contiguous SDW Slave registers
622  * @slave: SDW Slave
623  * @addr: Register address
624  * @count: length
625  * @val: Buffer for values to be written
626  *
627  * This version of the function will take a PM reference to the slave
628  * device.
629  * Note that if the message crosses a page boundary each page will be
630  * transferred under a separate invocation of the msg_lock.
631  */
632 int sdw_nwrite(struct sdw_slave *slave, u32 addr, size_t count, const u8 *val)
633 {
634 	int ret;
635 
636 	ret = pm_runtime_get_sync(&slave->dev);
637 	if (ret < 0 && ret != -EACCES) {
638 		pm_runtime_put_noidle(&slave->dev);
639 		return ret;
640 	}
641 
642 	ret = sdw_nwrite_no_pm(slave, addr, count, val);
643 
644 	pm_runtime_mark_last_busy(&slave->dev);
645 	pm_runtime_put(&slave->dev);
646 
647 	return ret;
648 }
649 EXPORT_SYMBOL(sdw_nwrite);
650 
651 /**
652  * sdw_read() - Read a SDW Slave register
653  * @slave: SDW Slave
654  * @addr: Register address
655  *
656  * This version of the function will take a PM reference to the slave
657  * device.
658  */
659 int sdw_read(struct sdw_slave *slave, u32 addr)
660 {
661 	u8 buf;
662 	int ret;
663 
664 	ret = sdw_nread(slave, addr, 1, &buf);
665 	if (ret < 0)
666 		return ret;
667 
668 	return buf;
669 }
670 EXPORT_SYMBOL(sdw_read);
671 
672 /**
673  * sdw_write() - Write a SDW Slave register
674  * @slave: SDW Slave
675  * @addr: Register address
676  * @value: Register value
677  *
678  * This version of the function will take a PM reference to the slave
679  * device.
680  */
681 int sdw_write(struct sdw_slave *slave, u32 addr, u8 value)
682 {
683 	return sdw_nwrite(slave, addr, 1, &value);
684 }
685 EXPORT_SYMBOL(sdw_write);
686 
687 /*
688  * SDW alert handling
689  */
690 
691 /* called with bus_lock held */
692 static struct sdw_slave *sdw_get_slave(struct sdw_bus *bus, int i)
693 {
694 	struct sdw_slave *slave;
695 
696 	list_for_each_entry(slave, &bus->slaves, node) {
697 		if (slave->dev_num == i)
698 			return slave;
699 	}
700 
701 	return NULL;
702 }
703 
704 int sdw_compare_devid(struct sdw_slave *slave, struct sdw_slave_id id)
705 {
706 	if (slave->id.mfg_id != id.mfg_id ||
707 	    slave->id.part_id != id.part_id ||
708 	    slave->id.class_id != id.class_id ||
709 	    (slave->id.unique_id != SDW_IGNORED_UNIQUE_ID &&
710 	     slave->id.unique_id != id.unique_id))
711 		return -ENODEV;
712 
713 	return 0;
714 }
715 EXPORT_SYMBOL(sdw_compare_devid);
716 
717 /* called with bus_lock held */
718 static int sdw_get_device_num(struct sdw_slave *slave)
719 {
720 	struct sdw_bus *bus = slave->bus;
721 	int bit;
722 
723 	if (bus->ops && bus->ops->get_device_num) {
724 		bit = bus->ops->get_device_num(bus, slave);
725 		if (bit < 0)
726 			goto err;
727 	} else {
728 		bit = find_first_zero_bit(bus->assigned, SDW_MAX_DEVICES);
729 		if (bit == SDW_MAX_DEVICES) {
730 			bit = -ENODEV;
731 			goto err;
732 		}
733 	}
734 
735 	/*
736 	 * Do not update dev_num in Slave data structure here,
737 	 * Update once program dev_num is successful
738 	 */
739 	set_bit(bit, bus->assigned);
740 
741 err:
742 	return bit;
743 }
744 
745 static int sdw_assign_device_num(struct sdw_slave *slave)
746 {
747 	struct sdw_bus *bus = slave->bus;
748 	int ret, dev_num;
749 	bool new_device = false;
750 
751 	/* check first if device number is assigned, if so reuse that */
752 	if (!slave->dev_num) {
753 		if (!slave->dev_num_sticky) {
754 			mutex_lock(&slave->bus->bus_lock);
755 			dev_num = sdw_get_device_num(slave);
756 			mutex_unlock(&slave->bus->bus_lock);
757 			if (dev_num < 0) {
758 				dev_err(bus->dev, "Get dev_num failed: %d\n",
759 					dev_num);
760 				return dev_num;
761 			}
762 			slave->dev_num = dev_num;
763 			slave->dev_num_sticky = dev_num;
764 			new_device = true;
765 		} else {
766 			slave->dev_num = slave->dev_num_sticky;
767 		}
768 	}
769 
770 	if (!new_device)
771 		dev_dbg(bus->dev,
772 			"Slave already registered, reusing dev_num:%d\n",
773 			slave->dev_num);
774 
775 	/* Clear the slave->dev_num to transfer message on device 0 */
776 	dev_num = slave->dev_num;
777 	slave->dev_num = 0;
778 
779 	ret = sdw_write_no_pm(slave, SDW_SCP_DEVNUMBER, dev_num);
780 	if (ret < 0) {
781 		dev_err(bus->dev, "Program device_num %d failed: %d\n",
782 			dev_num, ret);
783 		return ret;
784 	}
785 
786 	/* After xfer of msg, restore dev_num */
787 	slave->dev_num = slave->dev_num_sticky;
788 
789 	if (bus->ops && bus->ops->new_peripheral_assigned)
790 		bus->ops->new_peripheral_assigned(bus, slave, dev_num);
791 
792 	return 0;
793 }
794 
795 void sdw_extract_slave_id(struct sdw_bus *bus,
796 			  u64 addr, struct sdw_slave_id *id)
797 {
798 	dev_dbg(bus->dev, "SDW Slave Addr: %llx\n", addr);
799 
800 	id->sdw_version = SDW_VERSION(addr);
801 	id->unique_id = SDW_UNIQUE_ID(addr);
802 	id->mfg_id = SDW_MFG_ID(addr);
803 	id->part_id = SDW_PART_ID(addr);
804 	id->class_id = SDW_CLASS_ID(addr);
805 
806 	dev_dbg(bus->dev,
807 		"SDW Slave class_id 0x%02x, mfg_id 0x%04x, part_id 0x%04x, unique_id 0x%x, version 0x%x\n",
808 		id->class_id, id->mfg_id, id->part_id, id->unique_id, id->sdw_version);
809 }
810 EXPORT_SYMBOL(sdw_extract_slave_id);
811 
812 static int sdw_program_device_num(struct sdw_bus *bus, bool *programmed)
813 {
814 	u8 buf[SDW_NUM_DEV_ID_REGISTERS] = {0};
815 	struct sdw_slave *slave, *_s;
816 	struct sdw_slave_id id;
817 	struct sdw_msg msg;
818 	bool found;
819 	int count = 0, ret;
820 	u64 addr;
821 
822 	*programmed = false;
823 
824 	/* No Slave, so use raw xfer api */
825 	ret = sdw_fill_msg(&msg, NULL, SDW_SCP_DEVID_0,
826 			   SDW_NUM_DEV_ID_REGISTERS, 0, SDW_MSG_FLAG_READ, buf);
827 	if (ret < 0)
828 		return ret;
829 
830 	do {
831 		ret = sdw_transfer(bus, &msg);
832 		if (ret == -ENODATA) { /* end of device id reads */
833 			dev_dbg(bus->dev, "No more devices to enumerate\n");
834 			ret = 0;
835 			break;
836 		}
837 		if (ret < 0) {
838 			dev_err(bus->dev, "DEVID read fail:%d\n", ret);
839 			break;
840 		}
841 
842 		/*
843 		 * Construct the addr and extract. Cast the higher shift
844 		 * bits to avoid truncation due to size limit.
845 		 */
846 		addr = buf[5] | (buf[4] << 8) | (buf[3] << 16) |
847 			((u64)buf[2] << 24) | ((u64)buf[1] << 32) |
848 			((u64)buf[0] << 40);
849 
850 		sdw_extract_slave_id(bus, addr, &id);
851 
852 		found = false;
853 		/* Now compare with entries */
854 		list_for_each_entry_safe(slave, _s, &bus->slaves, node) {
855 			if (sdw_compare_devid(slave, id) == 0) {
856 				found = true;
857 
858 				/*
859 				 * To prevent skipping state-machine stages don't
860 				 * program a device until we've seen it UNATTACH.
861 				 * Must return here because no other device on #0
862 				 * can be detected until this one has been
863 				 * assigned a device ID.
864 				 */
865 				if (slave->status != SDW_SLAVE_UNATTACHED)
866 					return 0;
867 
868 				/*
869 				 * Assign a new dev_num to this Slave and
870 				 * not mark it present. It will be marked
871 				 * present after it reports ATTACHED on new
872 				 * dev_num
873 				 */
874 				ret = sdw_assign_device_num(slave);
875 				if (ret < 0) {
876 					dev_err(bus->dev,
877 						"Assign dev_num failed:%d\n",
878 						ret);
879 					return ret;
880 				}
881 
882 				*programmed = true;
883 
884 				break;
885 			}
886 		}
887 
888 		if (!found) {
889 			/* TODO: Park this device in Group 13 */
890 
891 			/*
892 			 * add Slave device even if there is no platform
893 			 * firmware description. There will be no driver probe
894 			 * but the user/integration will be able to see the
895 			 * device, enumeration status and device number in sysfs
896 			 */
897 			sdw_slave_add(bus, &id, NULL);
898 
899 			dev_err(bus->dev, "Slave Entry not found\n");
900 		}
901 
902 		count++;
903 
904 		/*
905 		 * Check till error out or retry (count) exhausts.
906 		 * Device can drop off and rejoin during enumeration
907 		 * so count till twice the bound.
908 		 */
909 
910 	} while (ret == 0 && count < (SDW_MAX_DEVICES * 2));
911 
912 	return ret;
913 }
914 
915 static void sdw_modify_slave_status(struct sdw_slave *slave,
916 				    enum sdw_slave_status status)
917 {
918 	struct sdw_bus *bus = slave->bus;
919 
920 	mutex_lock(&bus->bus_lock);
921 
922 	dev_vdbg(bus->dev,
923 		 "changing status slave %d status %d new status %d\n",
924 		 slave->dev_num, slave->status, status);
925 
926 	if (status == SDW_SLAVE_UNATTACHED) {
927 		dev_dbg(&slave->dev,
928 			"initializing enumeration and init completion for Slave %d\n",
929 			slave->dev_num);
930 
931 		reinit_completion(&slave->enumeration_complete);
932 		reinit_completion(&slave->initialization_complete);
933 
934 	} else if ((status == SDW_SLAVE_ATTACHED) &&
935 		   (slave->status == SDW_SLAVE_UNATTACHED)) {
936 		dev_dbg(&slave->dev,
937 			"signaling enumeration completion for Slave %d\n",
938 			slave->dev_num);
939 
940 		complete_all(&slave->enumeration_complete);
941 	}
942 	slave->status = status;
943 	mutex_unlock(&bus->bus_lock);
944 }
945 
946 static int sdw_slave_clk_stop_callback(struct sdw_slave *slave,
947 				       enum sdw_clk_stop_mode mode,
948 				       enum sdw_clk_stop_type type)
949 {
950 	int ret = 0;
951 
952 	mutex_lock(&slave->sdw_dev_lock);
953 
954 	if (slave->probed)  {
955 		struct device *dev = &slave->dev;
956 		struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
957 
958 		if (drv->ops && drv->ops->clk_stop)
959 			ret = drv->ops->clk_stop(slave, mode, type);
960 	}
961 
962 	mutex_unlock(&slave->sdw_dev_lock);
963 
964 	return ret;
965 }
966 
967 static int sdw_slave_clk_stop_prepare(struct sdw_slave *slave,
968 				      enum sdw_clk_stop_mode mode,
969 				      bool prepare)
970 {
971 	bool wake_en;
972 	u32 val = 0;
973 	int ret;
974 
975 	wake_en = slave->prop.wake_capable;
976 
977 	if (prepare) {
978 		val = SDW_SCP_SYSTEMCTRL_CLK_STP_PREP;
979 
980 		if (mode == SDW_CLK_STOP_MODE1)
981 			val |= SDW_SCP_SYSTEMCTRL_CLK_STP_MODE1;
982 
983 		if (wake_en)
984 			val |= SDW_SCP_SYSTEMCTRL_WAKE_UP_EN;
985 	} else {
986 		ret = sdw_read_no_pm(slave, SDW_SCP_SYSTEMCTRL);
987 		if (ret < 0) {
988 			if (ret != -ENODATA)
989 				dev_err(&slave->dev, "SDW_SCP_SYSTEMCTRL read failed:%d\n", ret);
990 			return ret;
991 		}
992 		val = ret;
993 		val &= ~(SDW_SCP_SYSTEMCTRL_CLK_STP_PREP);
994 	}
995 
996 	ret = sdw_write_no_pm(slave, SDW_SCP_SYSTEMCTRL, val);
997 
998 	if (ret < 0 && ret != -ENODATA)
999 		dev_err(&slave->dev, "SDW_SCP_SYSTEMCTRL write failed:%d\n", ret);
1000 
1001 	return ret;
1002 }
1003 
1004 static int sdw_bus_wait_for_clk_prep_deprep(struct sdw_bus *bus, u16 dev_num, bool prepare)
1005 {
1006 	int retry = bus->clk_stop_timeout;
1007 	int val;
1008 
1009 	do {
1010 		val = sdw_bread_no_pm(bus, dev_num, SDW_SCP_STAT);
1011 		if (val < 0) {
1012 			if (val != -ENODATA)
1013 				dev_err(bus->dev, "SDW_SCP_STAT bread failed:%d\n", val);
1014 			return val;
1015 		}
1016 		val &= SDW_SCP_STAT_CLK_STP_NF;
1017 		if (!val) {
1018 			dev_dbg(bus->dev, "clock stop %s done slave:%d\n",
1019 				prepare ? "prepare" : "deprepare",
1020 				dev_num);
1021 			return 0;
1022 		}
1023 
1024 		usleep_range(1000, 1500);
1025 		retry--;
1026 	} while (retry);
1027 
1028 	dev_dbg(bus->dev, "clock stop %s did not complete for slave:%d\n",
1029 		prepare ? "prepare" : "deprepare",
1030 		dev_num);
1031 
1032 	return -ETIMEDOUT;
1033 }
1034 
1035 /**
1036  * sdw_bus_prep_clk_stop: prepare Slave(s) for clock stop
1037  *
1038  * @bus: SDW bus instance
1039  *
1040  * Query Slave for clock stop mode and prepare for that mode.
1041  */
1042 int sdw_bus_prep_clk_stop(struct sdw_bus *bus)
1043 {
1044 	bool simple_clk_stop = true;
1045 	struct sdw_slave *slave;
1046 	bool is_slave = false;
1047 	int ret = 0;
1048 
1049 	/*
1050 	 * In order to save on transition time, prepare
1051 	 * each Slave and then wait for all Slave(s) to be
1052 	 * prepared for clock stop.
1053 	 * If one of the Slave devices has lost sync and
1054 	 * replies with Command Ignored/-ENODATA, we continue
1055 	 * the loop
1056 	 */
1057 	list_for_each_entry(slave, &bus->slaves, node) {
1058 		if (!slave->dev_num)
1059 			continue;
1060 
1061 		if (slave->status != SDW_SLAVE_ATTACHED &&
1062 		    slave->status != SDW_SLAVE_ALERT)
1063 			continue;
1064 
1065 		/* Identify if Slave(s) are available on Bus */
1066 		is_slave = true;
1067 
1068 		ret = sdw_slave_clk_stop_callback(slave,
1069 						  SDW_CLK_STOP_MODE0,
1070 						  SDW_CLK_PRE_PREPARE);
1071 		if (ret < 0 && ret != -ENODATA) {
1072 			dev_err(&slave->dev, "clock stop pre-prepare cb failed:%d\n", ret);
1073 			return ret;
1074 		}
1075 
1076 		/* Only prepare a Slave device if needed */
1077 		if (!slave->prop.simple_clk_stop_capable) {
1078 			simple_clk_stop = false;
1079 
1080 			ret = sdw_slave_clk_stop_prepare(slave,
1081 							 SDW_CLK_STOP_MODE0,
1082 							 true);
1083 			if (ret < 0 && ret != -ENODATA) {
1084 				dev_err(&slave->dev, "clock stop prepare failed:%d\n", ret);
1085 				return ret;
1086 			}
1087 		}
1088 	}
1089 
1090 	/* Skip remaining clock stop preparation if no Slave is attached */
1091 	if (!is_slave)
1092 		return 0;
1093 
1094 	/*
1095 	 * Don't wait for all Slaves to be ready if they follow the simple
1096 	 * state machine
1097 	 */
1098 	if (!simple_clk_stop) {
1099 		ret = sdw_bus_wait_for_clk_prep_deprep(bus,
1100 						       SDW_BROADCAST_DEV_NUM, true);
1101 		/*
1102 		 * if there are no Slave devices present and the reply is
1103 		 * Command_Ignored/-ENODATA, we don't need to continue with the
1104 		 * flow and can just return here. The error code is not modified
1105 		 * and its handling left as an exercise for the caller.
1106 		 */
1107 		if (ret < 0)
1108 			return ret;
1109 	}
1110 
1111 	/* Inform slaves that prep is done */
1112 	list_for_each_entry(slave, &bus->slaves, node) {
1113 		if (!slave->dev_num)
1114 			continue;
1115 
1116 		if (slave->status != SDW_SLAVE_ATTACHED &&
1117 		    slave->status != SDW_SLAVE_ALERT)
1118 			continue;
1119 
1120 		ret = sdw_slave_clk_stop_callback(slave,
1121 						  SDW_CLK_STOP_MODE0,
1122 						  SDW_CLK_POST_PREPARE);
1123 
1124 		if (ret < 0 && ret != -ENODATA) {
1125 			dev_err(&slave->dev, "clock stop post-prepare cb failed:%d\n", ret);
1126 			return ret;
1127 		}
1128 	}
1129 
1130 	return 0;
1131 }
1132 EXPORT_SYMBOL(sdw_bus_prep_clk_stop);
1133 
1134 /**
1135  * sdw_bus_clk_stop: stop bus clock
1136  *
1137  * @bus: SDW bus instance
1138  *
1139  * After preparing the Slaves for clock stop, stop the clock by broadcasting
1140  * write to SCP_CTRL register.
1141  */
1142 int sdw_bus_clk_stop(struct sdw_bus *bus)
1143 {
1144 	int ret;
1145 
1146 	/*
1147 	 * broadcast clock stop now, attached Slaves will ACK this,
1148 	 * unattached will ignore
1149 	 */
1150 	ret = sdw_bwrite_no_pm(bus, SDW_BROADCAST_DEV_NUM,
1151 			       SDW_SCP_CTRL, SDW_SCP_CTRL_CLK_STP_NOW);
1152 	if (ret < 0) {
1153 		if (ret != -ENODATA)
1154 			dev_err(bus->dev, "ClockStopNow Broadcast msg failed %d\n", ret);
1155 		return ret;
1156 	}
1157 
1158 	return 0;
1159 }
1160 EXPORT_SYMBOL(sdw_bus_clk_stop);
1161 
1162 /**
1163  * sdw_bus_exit_clk_stop: Exit clock stop mode
1164  *
1165  * @bus: SDW bus instance
1166  *
1167  * This De-prepares the Slaves by exiting Clock Stop Mode 0. For the Slaves
1168  * exiting Clock Stop Mode 1, they will be de-prepared after they enumerate
1169  * back.
1170  */
1171 int sdw_bus_exit_clk_stop(struct sdw_bus *bus)
1172 {
1173 	bool simple_clk_stop = true;
1174 	struct sdw_slave *slave;
1175 	bool is_slave = false;
1176 	int ret;
1177 
1178 	/*
1179 	 * In order to save on transition time, de-prepare
1180 	 * each Slave and then wait for all Slave(s) to be
1181 	 * de-prepared after clock resume.
1182 	 */
1183 	list_for_each_entry(slave, &bus->slaves, node) {
1184 		if (!slave->dev_num)
1185 			continue;
1186 
1187 		if (slave->status != SDW_SLAVE_ATTACHED &&
1188 		    slave->status != SDW_SLAVE_ALERT)
1189 			continue;
1190 
1191 		/* Identify if Slave(s) are available on Bus */
1192 		is_slave = true;
1193 
1194 		ret = sdw_slave_clk_stop_callback(slave, SDW_CLK_STOP_MODE0,
1195 						  SDW_CLK_PRE_DEPREPARE);
1196 		if (ret < 0)
1197 			dev_warn(&slave->dev, "clock stop pre-deprepare cb failed:%d\n", ret);
1198 
1199 		/* Only de-prepare a Slave device if needed */
1200 		if (!slave->prop.simple_clk_stop_capable) {
1201 			simple_clk_stop = false;
1202 
1203 			ret = sdw_slave_clk_stop_prepare(slave, SDW_CLK_STOP_MODE0,
1204 							 false);
1205 
1206 			if (ret < 0)
1207 				dev_warn(&slave->dev, "clock stop deprepare failed:%d\n", ret);
1208 		}
1209 	}
1210 
1211 	/* Skip remaining clock stop de-preparation if no Slave is attached */
1212 	if (!is_slave)
1213 		return 0;
1214 
1215 	/*
1216 	 * Don't wait for all Slaves to be ready if they follow the simple
1217 	 * state machine
1218 	 */
1219 	if (!simple_clk_stop) {
1220 		ret = sdw_bus_wait_for_clk_prep_deprep(bus, SDW_BROADCAST_DEV_NUM, false);
1221 		if (ret < 0)
1222 			dev_warn(bus->dev, "clock stop deprepare wait failed:%d\n", ret);
1223 	}
1224 
1225 	list_for_each_entry(slave, &bus->slaves, node) {
1226 		if (!slave->dev_num)
1227 			continue;
1228 
1229 		if (slave->status != SDW_SLAVE_ATTACHED &&
1230 		    slave->status != SDW_SLAVE_ALERT)
1231 			continue;
1232 
1233 		ret = sdw_slave_clk_stop_callback(slave, SDW_CLK_STOP_MODE0,
1234 						  SDW_CLK_POST_DEPREPARE);
1235 		if (ret < 0)
1236 			dev_warn(&slave->dev, "clock stop post-deprepare cb failed:%d\n", ret);
1237 	}
1238 
1239 	return 0;
1240 }
1241 EXPORT_SYMBOL(sdw_bus_exit_clk_stop);
1242 
1243 int sdw_configure_dpn_intr(struct sdw_slave *slave,
1244 			   int port, bool enable, int mask)
1245 {
1246 	u32 addr;
1247 	int ret;
1248 	u8 val = 0;
1249 
1250 	if (slave->bus->params.s_data_mode != SDW_PORT_DATA_MODE_NORMAL) {
1251 		dev_dbg(&slave->dev, "TEST FAIL interrupt %s\n",
1252 			enable ? "on" : "off");
1253 		mask |= SDW_DPN_INT_TEST_FAIL;
1254 	}
1255 
1256 	addr = SDW_DPN_INTMASK(port);
1257 
1258 	/* Set/Clear port ready interrupt mask */
1259 	if (enable) {
1260 		val |= mask;
1261 		val |= SDW_DPN_INT_PORT_READY;
1262 	} else {
1263 		val &= ~(mask);
1264 		val &= ~SDW_DPN_INT_PORT_READY;
1265 	}
1266 
1267 	ret = sdw_update_no_pm(slave, addr, (mask | SDW_DPN_INT_PORT_READY), val);
1268 	if (ret < 0)
1269 		dev_err(&slave->dev,
1270 			"SDW_DPN_INTMASK write failed:%d\n", val);
1271 
1272 	return ret;
1273 }
1274 
1275 static int sdw_slave_set_frequency(struct sdw_slave *slave)
1276 {
1277 	u32 mclk_freq = slave->bus->prop.mclk_freq;
1278 	u32 curr_freq = slave->bus->params.curr_dr_freq >> 1;
1279 	unsigned int scale;
1280 	u8 scale_index;
1281 	u8 base;
1282 	int ret;
1283 
1284 	/*
1285 	 * frequency base and scale registers are required for SDCA
1286 	 * devices. They may also be used for 1.2+/non-SDCA devices.
1287 	 * Driver can set the property, we will need a DisCo property
1288 	 * to discover this case from platform firmware.
1289 	 */
1290 	if (!slave->id.class_id && !slave->prop.clock_reg_supported)
1291 		return 0;
1292 
1293 	if (!mclk_freq) {
1294 		dev_err(&slave->dev,
1295 			"no bus MCLK, cannot set SDW_SCP_BUS_CLOCK_BASE\n");
1296 		return -EINVAL;
1297 	}
1298 
1299 	/*
1300 	 * map base frequency using Table 89 of SoundWire 1.2 spec.
1301 	 * The order of the tests just follows the specification, this
1302 	 * is not a selection between possible values or a search for
1303 	 * the best value but just a mapping.  Only one case per platform
1304 	 * is relevant.
1305 	 * Some BIOS have inconsistent values for mclk_freq but a
1306 	 * correct root so we force the mclk_freq to avoid variations.
1307 	 */
1308 	if (!(19200000 % mclk_freq)) {
1309 		mclk_freq = 19200000;
1310 		base = SDW_SCP_BASE_CLOCK_19200000_HZ;
1311 	} else if (!(24000000 % mclk_freq)) {
1312 		mclk_freq = 24000000;
1313 		base = SDW_SCP_BASE_CLOCK_24000000_HZ;
1314 	} else if (!(24576000 % mclk_freq)) {
1315 		mclk_freq = 24576000;
1316 		base = SDW_SCP_BASE_CLOCK_24576000_HZ;
1317 	} else if (!(22579200 % mclk_freq)) {
1318 		mclk_freq = 22579200;
1319 		base = SDW_SCP_BASE_CLOCK_22579200_HZ;
1320 	} else if (!(32000000 % mclk_freq)) {
1321 		mclk_freq = 32000000;
1322 		base = SDW_SCP_BASE_CLOCK_32000000_HZ;
1323 	} else {
1324 		dev_err(&slave->dev,
1325 			"Unsupported clock base, mclk %d\n",
1326 			mclk_freq);
1327 		return -EINVAL;
1328 	}
1329 
1330 	if (mclk_freq % curr_freq) {
1331 		dev_err(&slave->dev,
1332 			"mclk %d is not multiple of bus curr_freq %d\n",
1333 			mclk_freq, curr_freq);
1334 		return -EINVAL;
1335 	}
1336 
1337 	scale = mclk_freq / curr_freq;
1338 
1339 	/*
1340 	 * map scale to Table 90 of SoundWire 1.2 spec - and check
1341 	 * that the scale is a power of two and maximum 64
1342 	 */
1343 	scale_index = ilog2(scale);
1344 
1345 	if (BIT(scale_index) != scale || scale_index > 6) {
1346 		dev_err(&slave->dev,
1347 			"No match found for scale %d, bus mclk %d curr_freq %d\n",
1348 			scale, mclk_freq, curr_freq);
1349 		return -EINVAL;
1350 	}
1351 	scale_index++;
1352 
1353 	ret = sdw_write_no_pm(slave, SDW_SCP_BUS_CLOCK_BASE, base);
1354 	if (ret < 0) {
1355 		dev_err(&slave->dev,
1356 			"SDW_SCP_BUS_CLOCK_BASE write failed:%d\n", ret);
1357 		return ret;
1358 	}
1359 
1360 	/* initialize scale for both banks */
1361 	ret = sdw_write_no_pm(slave, SDW_SCP_BUSCLOCK_SCALE_B0, scale_index);
1362 	if (ret < 0) {
1363 		dev_err(&slave->dev,
1364 			"SDW_SCP_BUSCLOCK_SCALE_B0 write failed:%d\n", ret);
1365 		return ret;
1366 	}
1367 	ret = sdw_write_no_pm(slave, SDW_SCP_BUSCLOCK_SCALE_B1, scale_index);
1368 	if (ret < 0)
1369 		dev_err(&slave->dev,
1370 			"SDW_SCP_BUSCLOCK_SCALE_B1 write failed:%d\n", ret);
1371 
1372 	dev_dbg(&slave->dev,
1373 		"Configured bus base %d, scale %d, mclk %d, curr_freq %d\n",
1374 		base, scale_index, mclk_freq, curr_freq);
1375 
1376 	return ret;
1377 }
1378 
1379 static int sdw_initialize_slave(struct sdw_slave *slave)
1380 {
1381 	struct sdw_slave_prop *prop = &slave->prop;
1382 	int status;
1383 	int ret;
1384 	u8 val;
1385 
1386 	ret = sdw_slave_set_frequency(slave);
1387 	if (ret < 0)
1388 		return ret;
1389 
1390 	if (slave->bus->prop.quirks & SDW_MASTER_QUIRKS_CLEAR_INITIAL_CLASH) {
1391 		/* Clear bus clash interrupt before enabling interrupt mask */
1392 		status = sdw_read_no_pm(slave, SDW_SCP_INT1);
1393 		if (status < 0) {
1394 			dev_err(&slave->dev,
1395 				"SDW_SCP_INT1 (BUS_CLASH) read failed:%d\n", status);
1396 			return status;
1397 		}
1398 		if (status & SDW_SCP_INT1_BUS_CLASH) {
1399 			dev_warn(&slave->dev, "Bus clash detected before INT mask is enabled\n");
1400 			ret = sdw_write_no_pm(slave, SDW_SCP_INT1, SDW_SCP_INT1_BUS_CLASH);
1401 			if (ret < 0) {
1402 				dev_err(&slave->dev,
1403 					"SDW_SCP_INT1 (BUS_CLASH) write failed:%d\n", ret);
1404 				return ret;
1405 			}
1406 		}
1407 	}
1408 	if ((slave->bus->prop.quirks & SDW_MASTER_QUIRKS_CLEAR_INITIAL_PARITY) &&
1409 	    !(slave->prop.quirks & SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY)) {
1410 		/* Clear parity interrupt before enabling interrupt mask */
1411 		status = sdw_read_no_pm(slave, SDW_SCP_INT1);
1412 		if (status < 0) {
1413 			dev_err(&slave->dev,
1414 				"SDW_SCP_INT1 (PARITY) read failed:%d\n", status);
1415 			return status;
1416 		}
1417 		if (status & SDW_SCP_INT1_PARITY) {
1418 			dev_warn(&slave->dev, "PARITY error detected before INT mask is enabled\n");
1419 			ret = sdw_write_no_pm(slave, SDW_SCP_INT1, SDW_SCP_INT1_PARITY);
1420 			if (ret < 0) {
1421 				dev_err(&slave->dev,
1422 					"SDW_SCP_INT1 (PARITY) write failed:%d\n", ret);
1423 				return ret;
1424 			}
1425 		}
1426 	}
1427 
1428 	/*
1429 	 * Set SCP_INT1_MASK register, typically bus clash and
1430 	 * implementation-defined interrupt mask. The Parity detection
1431 	 * may not always be correct on startup so its use is
1432 	 * device-dependent, it might e.g. only be enabled in
1433 	 * steady-state after a couple of frames.
1434 	 */
1435 	val = slave->prop.scp_int1_mask;
1436 
1437 	/* Enable SCP interrupts */
1438 	ret = sdw_update_no_pm(slave, SDW_SCP_INTMASK1, val, val);
1439 	if (ret < 0) {
1440 		dev_err(&slave->dev,
1441 			"SDW_SCP_INTMASK1 write failed:%d\n", ret);
1442 		return ret;
1443 	}
1444 
1445 	/* No need to continue if DP0 is not present */
1446 	if (!slave->prop.dp0_prop)
1447 		return 0;
1448 
1449 	/* Enable DP0 interrupts */
1450 	val = prop->dp0_prop->imp_def_interrupts;
1451 	val |= SDW_DP0_INT_PORT_READY | SDW_DP0_INT_BRA_FAILURE;
1452 
1453 	ret = sdw_update_no_pm(slave, SDW_DP0_INTMASK, val, val);
1454 	if (ret < 0)
1455 		dev_err(&slave->dev,
1456 			"SDW_DP0_INTMASK read failed:%d\n", ret);
1457 	return ret;
1458 }
1459 
1460 static int sdw_handle_dp0_interrupt(struct sdw_slave *slave, u8 *slave_status)
1461 {
1462 	u8 clear, impl_int_mask;
1463 	int status, status2, ret, count = 0;
1464 
1465 	status = sdw_read_no_pm(slave, SDW_DP0_INT);
1466 	if (status < 0) {
1467 		dev_err(&slave->dev,
1468 			"SDW_DP0_INT read failed:%d\n", status);
1469 		return status;
1470 	}
1471 
1472 	do {
1473 		clear = status & ~SDW_DP0_INTERRUPTS;
1474 
1475 		if (status & SDW_DP0_INT_TEST_FAIL) {
1476 			dev_err(&slave->dev, "Test fail for port 0\n");
1477 			clear |= SDW_DP0_INT_TEST_FAIL;
1478 		}
1479 
1480 		/*
1481 		 * Assumption: PORT_READY interrupt will be received only for
1482 		 * ports implementing Channel Prepare state machine (CP_SM)
1483 		 */
1484 
1485 		if (status & SDW_DP0_INT_PORT_READY) {
1486 			complete(&slave->port_ready[0]);
1487 			clear |= SDW_DP0_INT_PORT_READY;
1488 		}
1489 
1490 		if (status & SDW_DP0_INT_BRA_FAILURE) {
1491 			dev_err(&slave->dev, "BRA failed\n");
1492 			clear |= SDW_DP0_INT_BRA_FAILURE;
1493 		}
1494 
1495 		impl_int_mask = SDW_DP0_INT_IMPDEF1 |
1496 			SDW_DP0_INT_IMPDEF2 | SDW_DP0_INT_IMPDEF3;
1497 
1498 		if (status & impl_int_mask) {
1499 			clear |= impl_int_mask;
1500 			*slave_status = clear;
1501 		}
1502 
1503 		/* clear the interrupts but don't touch reserved and SDCA_CASCADE fields */
1504 		ret = sdw_write_no_pm(slave, SDW_DP0_INT, clear);
1505 		if (ret < 0) {
1506 			dev_err(&slave->dev,
1507 				"SDW_DP0_INT write failed:%d\n", ret);
1508 			return ret;
1509 		}
1510 
1511 		/* Read DP0 interrupt again */
1512 		status2 = sdw_read_no_pm(slave, SDW_DP0_INT);
1513 		if (status2 < 0) {
1514 			dev_err(&slave->dev,
1515 				"SDW_DP0_INT read failed:%d\n", status2);
1516 			return status2;
1517 		}
1518 		/* filter to limit loop to interrupts identified in the first status read */
1519 		status &= status2;
1520 
1521 		count++;
1522 
1523 		/* we can get alerts while processing so keep retrying */
1524 	} while ((status & SDW_DP0_INTERRUPTS) && (count < SDW_READ_INTR_CLEAR_RETRY));
1525 
1526 	if (count == SDW_READ_INTR_CLEAR_RETRY)
1527 		dev_warn(&slave->dev, "Reached MAX_RETRY on DP0 read\n");
1528 
1529 	return ret;
1530 }
1531 
1532 static int sdw_handle_port_interrupt(struct sdw_slave *slave,
1533 				     int port, u8 *slave_status)
1534 {
1535 	u8 clear, impl_int_mask;
1536 	int status, status2, ret, count = 0;
1537 	u32 addr;
1538 
1539 	if (port == 0)
1540 		return sdw_handle_dp0_interrupt(slave, slave_status);
1541 
1542 	addr = SDW_DPN_INT(port);
1543 	status = sdw_read_no_pm(slave, addr);
1544 	if (status < 0) {
1545 		dev_err(&slave->dev,
1546 			"SDW_DPN_INT read failed:%d\n", status);
1547 
1548 		return status;
1549 	}
1550 
1551 	do {
1552 		clear = status & ~SDW_DPN_INTERRUPTS;
1553 
1554 		if (status & SDW_DPN_INT_TEST_FAIL) {
1555 			dev_err(&slave->dev, "Test fail for port:%d\n", port);
1556 			clear |= SDW_DPN_INT_TEST_FAIL;
1557 		}
1558 
1559 		/*
1560 		 * Assumption: PORT_READY interrupt will be received only
1561 		 * for ports implementing CP_SM.
1562 		 */
1563 		if (status & SDW_DPN_INT_PORT_READY) {
1564 			complete(&slave->port_ready[port]);
1565 			clear |= SDW_DPN_INT_PORT_READY;
1566 		}
1567 
1568 		impl_int_mask = SDW_DPN_INT_IMPDEF1 |
1569 			SDW_DPN_INT_IMPDEF2 | SDW_DPN_INT_IMPDEF3;
1570 
1571 		if (status & impl_int_mask) {
1572 			clear |= impl_int_mask;
1573 			*slave_status = clear;
1574 		}
1575 
1576 		/* clear the interrupt but don't touch reserved fields */
1577 		ret = sdw_write_no_pm(slave, addr, clear);
1578 		if (ret < 0) {
1579 			dev_err(&slave->dev,
1580 				"SDW_DPN_INT write failed:%d\n", ret);
1581 			return ret;
1582 		}
1583 
1584 		/* Read DPN interrupt again */
1585 		status2 = sdw_read_no_pm(slave, addr);
1586 		if (status2 < 0) {
1587 			dev_err(&slave->dev,
1588 				"SDW_DPN_INT read failed:%d\n", status2);
1589 			return status2;
1590 		}
1591 		/* filter to limit loop to interrupts identified in the first status read */
1592 		status &= status2;
1593 
1594 		count++;
1595 
1596 		/* we can get alerts while processing so keep retrying */
1597 	} while ((status & SDW_DPN_INTERRUPTS) && (count < SDW_READ_INTR_CLEAR_RETRY));
1598 
1599 	if (count == SDW_READ_INTR_CLEAR_RETRY)
1600 		dev_warn(&slave->dev, "Reached MAX_RETRY on port read");
1601 
1602 	return ret;
1603 }
1604 
1605 static int sdw_handle_slave_alerts(struct sdw_slave *slave)
1606 {
1607 	struct sdw_slave_intr_status slave_intr;
1608 	u8 clear = 0, bit, port_status[15] = {0};
1609 	int port_num, stat, ret, count = 0;
1610 	unsigned long port;
1611 	bool slave_notify;
1612 	u8 sdca_cascade = 0;
1613 	u8 buf, buf2[2];
1614 	bool parity_check;
1615 	bool parity_quirk;
1616 
1617 	sdw_modify_slave_status(slave, SDW_SLAVE_ALERT);
1618 
1619 	ret = pm_runtime_get_sync(&slave->dev);
1620 	if (ret < 0 && ret != -EACCES) {
1621 		dev_err(&slave->dev, "Failed to resume device: %d\n", ret);
1622 		pm_runtime_put_noidle(&slave->dev);
1623 		return ret;
1624 	}
1625 
1626 	/* Read Intstat 1, Intstat 2 and Intstat 3 registers */
1627 	ret = sdw_read_no_pm(slave, SDW_SCP_INT1);
1628 	if (ret < 0) {
1629 		dev_err(&slave->dev,
1630 			"SDW_SCP_INT1 read failed:%d\n", ret);
1631 		goto io_err;
1632 	}
1633 	buf = ret;
1634 
1635 	ret = sdw_nread_no_pm(slave, SDW_SCP_INTSTAT2, 2, buf2);
1636 	if (ret < 0) {
1637 		dev_err(&slave->dev,
1638 			"SDW_SCP_INT2/3 read failed:%d\n", ret);
1639 		goto io_err;
1640 	}
1641 
1642 	if (slave->id.class_id) {
1643 		ret = sdw_read_no_pm(slave, SDW_DP0_INT);
1644 		if (ret < 0) {
1645 			dev_err(&slave->dev,
1646 				"SDW_DP0_INT read failed:%d\n", ret);
1647 			goto io_err;
1648 		}
1649 		sdca_cascade = ret & SDW_DP0_SDCA_CASCADE;
1650 	}
1651 
1652 	do {
1653 		slave_notify = false;
1654 
1655 		/*
1656 		 * Check parity, bus clash and Slave (impl defined)
1657 		 * interrupt
1658 		 */
1659 		if (buf & SDW_SCP_INT1_PARITY) {
1660 			parity_check = slave->prop.scp_int1_mask & SDW_SCP_INT1_PARITY;
1661 			parity_quirk = !slave->first_interrupt_done &&
1662 				(slave->prop.quirks & SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY);
1663 
1664 			if (parity_check && !parity_quirk)
1665 				dev_err(&slave->dev, "Parity error detected\n");
1666 			clear |= SDW_SCP_INT1_PARITY;
1667 		}
1668 
1669 		if (buf & SDW_SCP_INT1_BUS_CLASH) {
1670 			if (slave->prop.scp_int1_mask & SDW_SCP_INT1_BUS_CLASH)
1671 				dev_err(&slave->dev, "Bus clash detected\n");
1672 			clear |= SDW_SCP_INT1_BUS_CLASH;
1673 		}
1674 
1675 		/*
1676 		 * When bus clash or parity errors are detected, such errors
1677 		 * are unlikely to be recoverable errors.
1678 		 * TODO: In such scenario, reset bus. Make this configurable
1679 		 * via sysfs property with bus reset being the default.
1680 		 */
1681 
1682 		if (buf & SDW_SCP_INT1_IMPL_DEF) {
1683 			if (slave->prop.scp_int1_mask & SDW_SCP_INT1_IMPL_DEF) {
1684 				dev_dbg(&slave->dev, "Slave impl defined interrupt\n");
1685 				slave_notify = true;
1686 			}
1687 			clear |= SDW_SCP_INT1_IMPL_DEF;
1688 		}
1689 
1690 		/* the SDCA interrupts are cleared in the codec driver .interrupt_callback() */
1691 		if (sdca_cascade)
1692 			slave_notify = true;
1693 
1694 		/* Check port 0 - 3 interrupts */
1695 		port = buf & SDW_SCP_INT1_PORT0_3;
1696 
1697 		/* To get port number corresponding to bits, shift it */
1698 		port = FIELD_GET(SDW_SCP_INT1_PORT0_3, port);
1699 		for_each_set_bit(bit, &port, 8) {
1700 			sdw_handle_port_interrupt(slave, bit,
1701 						  &port_status[bit]);
1702 		}
1703 
1704 		/* Check if cascade 2 interrupt is present */
1705 		if (buf & SDW_SCP_INT1_SCP2_CASCADE) {
1706 			port = buf2[0] & SDW_SCP_INTSTAT2_PORT4_10;
1707 			for_each_set_bit(bit, &port, 8) {
1708 				/* scp2 ports start from 4 */
1709 				port_num = bit + 4;
1710 				sdw_handle_port_interrupt(slave,
1711 						port_num,
1712 						&port_status[port_num]);
1713 			}
1714 		}
1715 
1716 		/* now check last cascade */
1717 		if (buf2[0] & SDW_SCP_INTSTAT2_SCP3_CASCADE) {
1718 			port = buf2[1] & SDW_SCP_INTSTAT3_PORT11_14;
1719 			for_each_set_bit(bit, &port, 8) {
1720 				/* scp3 ports start from 11 */
1721 				port_num = bit + 11;
1722 				sdw_handle_port_interrupt(slave,
1723 						port_num,
1724 						&port_status[port_num]);
1725 			}
1726 		}
1727 
1728 		/* Update the Slave driver */
1729 		if (slave_notify) {
1730 			mutex_lock(&slave->sdw_dev_lock);
1731 
1732 			if (slave->probed) {
1733 				struct device *dev = &slave->dev;
1734 				struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
1735 
1736 				if (slave->prop.use_domain_irq && slave->irq)
1737 					handle_nested_irq(slave->irq);
1738 
1739 				if (drv->ops && drv->ops->interrupt_callback) {
1740 					slave_intr.sdca_cascade = sdca_cascade;
1741 					slave_intr.control_port = clear;
1742 					memcpy(slave_intr.port, &port_status,
1743 					       sizeof(slave_intr.port));
1744 
1745 					drv->ops->interrupt_callback(slave, &slave_intr);
1746 				}
1747 			}
1748 
1749 			mutex_unlock(&slave->sdw_dev_lock);
1750 		}
1751 
1752 		/* Ack interrupt */
1753 		ret = sdw_write_no_pm(slave, SDW_SCP_INT1, clear);
1754 		if (ret < 0) {
1755 			dev_err(&slave->dev,
1756 				"SDW_SCP_INT1 write failed:%d\n", ret);
1757 			goto io_err;
1758 		}
1759 
1760 		/* at this point all initial interrupt sources were handled */
1761 		slave->first_interrupt_done = true;
1762 
1763 		/*
1764 		 * Read status again to ensure no new interrupts arrived
1765 		 * while servicing interrupts.
1766 		 */
1767 		ret = sdw_read_no_pm(slave, SDW_SCP_INT1);
1768 		if (ret < 0) {
1769 			dev_err(&slave->dev,
1770 				"SDW_SCP_INT1 recheck read failed:%d\n", ret);
1771 			goto io_err;
1772 		}
1773 		buf = ret;
1774 
1775 		ret = sdw_nread_no_pm(slave, SDW_SCP_INTSTAT2, 2, buf2);
1776 		if (ret < 0) {
1777 			dev_err(&slave->dev,
1778 				"SDW_SCP_INT2/3 recheck read failed:%d\n", ret);
1779 			goto io_err;
1780 		}
1781 
1782 		if (slave->id.class_id) {
1783 			ret = sdw_read_no_pm(slave, SDW_DP0_INT);
1784 			if (ret < 0) {
1785 				dev_err(&slave->dev,
1786 					"SDW_DP0_INT recheck read failed:%d\n", ret);
1787 				goto io_err;
1788 			}
1789 			sdca_cascade = ret & SDW_DP0_SDCA_CASCADE;
1790 		}
1791 
1792 		/*
1793 		 * Make sure no interrupts are pending
1794 		 */
1795 		stat = buf || buf2[0] || buf2[1] || sdca_cascade;
1796 
1797 		/*
1798 		 * Exit loop if Slave is continuously in ALERT state even
1799 		 * after servicing the interrupt multiple times.
1800 		 */
1801 		count++;
1802 
1803 		/* we can get alerts while processing so keep retrying */
1804 	} while (stat != 0 && count < SDW_READ_INTR_CLEAR_RETRY);
1805 
1806 	if (count == SDW_READ_INTR_CLEAR_RETRY)
1807 		dev_warn(&slave->dev, "Reached MAX_RETRY on alert read\n");
1808 
1809 io_err:
1810 	pm_runtime_mark_last_busy(&slave->dev);
1811 	pm_runtime_put_autosuspend(&slave->dev);
1812 
1813 	return ret;
1814 }
1815 
1816 static int sdw_update_slave_status(struct sdw_slave *slave,
1817 				   enum sdw_slave_status status)
1818 {
1819 	int ret = 0;
1820 
1821 	mutex_lock(&slave->sdw_dev_lock);
1822 
1823 	if (slave->probed) {
1824 		struct device *dev = &slave->dev;
1825 		struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
1826 
1827 		if (drv->ops && drv->ops->update_status)
1828 			ret = drv->ops->update_status(slave, status);
1829 	}
1830 
1831 	mutex_unlock(&slave->sdw_dev_lock);
1832 
1833 	return ret;
1834 }
1835 
1836 /**
1837  * sdw_handle_slave_status() - Handle Slave status
1838  * @bus: SDW bus instance
1839  * @status: Status for all Slave(s)
1840  */
1841 int sdw_handle_slave_status(struct sdw_bus *bus,
1842 			    enum sdw_slave_status status[])
1843 {
1844 	enum sdw_slave_status prev_status;
1845 	struct sdw_slave *slave;
1846 	bool attached_initializing, id_programmed;
1847 	int i, ret = 0;
1848 
1849 	/* first check if any Slaves fell off the bus */
1850 	for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1851 		mutex_lock(&bus->bus_lock);
1852 		if (test_bit(i, bus->assigned) == false) {
1853 			mutex_unlock(&bus->bus_lock);
1854 			continue;
1855 		}
1856 		mutex_unlock(&bus->bus_lock);
1857 
1858 		slave = sdw_get_slave(bus, i);
1859 		if (!slave)
1860 			continue;
1861 
1862 		if (status[i] == SDW_SLAVE_UNATTACHED &&
1863 		    slave->status != SDW_SLAVE_UNATTACHED) {
1864 			dev_warn(&slave->dev, "Slave %d state check1: UNATTACHED, status was %d\n",
1865 				 i, slave->status);
1866 			sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
1867 
1868 			/* Ensure driver knows that peripheral unattached */
1869 			ret = sdw_update_slave_status(slave, status[i]);
1870 			if (ret < 0)
1871 				dev_warn(&slave->dev, "Update Slave status failed:%d\n", ret);
1872 		}
1873 	}
1874 
1875 	if (status[0] == SDW_SLAVE_ATTACHED) {
1876 		dev_dbg(bus->dev, "Slave attached, programming device number\n");
1877 
1878 		/*
1879 		 * Programming a device number will have side effects,
1880 		 * so we deal with other devices at a later time.
1881 		 * This relies on those devices reporting ATTACHED, which will
1882 		 * trigger another call to this function. This will only
1883 		 * happen if at least one device ID was programmed.
1884 		 * Error returns from sdw_program_device_num() are currently
1885 		 * ignored because there's no useful recovery that can be done.
1886 		 * Returning the error here could result in the current status
1887 		 * of other devices not being handled, because if no device IDs
1888 		 * were programmed there's nothing to guarantee a status change
1889 		 * to trigger another call to this function.
1890 		 */
1891 		sdw_program_device_num(bus, &id_programmed);
1892 		if (id_programmed)
1893 			return 0;
1894 	}
1895 
1896 	/* Continue to check other slave statuses */
1897 	for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1898 		mutex_lock(&bus->bus_lock);
1899 		if (test_bit(i, bus->assigned) == false) {
1900 			mutex_unlock(&bus->bus_lock);
1901 			continue;
1902 		}
1903 		mutex_unlock(&bus->bus_lock);
1904 
1905 		slave = sdw_get_slave(bus, i);
1906 		if (!slave)
1907 			continue;
1908 
1909 		attached_initializing = false;
1910 
1911 		switch (status[i]) {
1912 		case SDW_SLAVE_UNATTACHED:
1913 			if (slave->status == SDW_SLAVE_UNATTACHED)
1914 				break;
1915 
1916 			dev_warn(&slave->dev, "Slave %d state check2: UNATTACHED, status was %d\n",
1917 				 i, slave->status);
1918 
1919 			sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
1920 			break;
1921 
1922 		case SDW_SLAVE_ALERT:
1923 			ret = sdw_handle_slave_alerts(slave);
1924 			if (ret < 0)
1925 				dev_err(&slave->dev,
1926 					"Slave %d alert handling failed: %d\n",
1927 					i, ret);
1928 			break;
1929 
1930 		case SDW_SLAVE_ATTACHED:
1931 			if (slave->status == SDW_SLAVE_ATTACHED)
1932 				break;
1933 
1934 			prev_status = slave->status;
1935 			sdw_modify_slave_status(slave, SDW_SLAVE_ATTACHED);
1936 
1937 			if (prev_status == SDW_SLAVE_ALERT)
1938 				break;
1939 
1940 			attached_initializing = true;
1941 
1942 			ret = sdw_initialize_slave(slave);
1943 			if (ret < 0)
1944 				dev_err(&slave->dev,
1945 					"Slave %d initialization failed: %d\n",
1946 					i, ret);
1947 
1948 			break;
1949 
1950 		default:
1951 			dev_err(&slave->dev, "Invalid slave %d status:%d\n",
1952 				i, status[i]);
1953 			break;
1954 		}
1955 
1956 		ret = sdw_update_slave_status(slave, status[i]);
1957 		if (ret < 0)
1958 			dev_err(&slave->dev,
1959 				"Update Slave status failed:%d\n", ret);
1960 		if (attached_initializing) {
1961 			dev_dbg(&slave->dev,
1962 				"signaling initialization completion for Slave %d\n",
1963 				slave->dev_num);
1964 
1965 			complete_all(&slave->initialization_complete);
1966 
1967 			/*
1968 			 * If the manager became pm_runtime active, the peripherals will be
1969 			 * restarted and attach, but their pm_runtime status may remain
1970 			 * suspended. If the 'update_slave_status' callback initiates
1971 			 * any sort of deferred processing, this processing would not be
1972 			 * cancelled on pm_runtime suspend.
1973 			 * To avoid such zombie states, we queue a request to resume.
1974 			 * This would be a no-op in case the peripheral was being resumed
1975 			 * by e.g. the ALSA/ASoC framework.
1976 			 */
1977 			pm_request_resume(&slave->dev);
1978 		}
1979 	}
1980 
1981 	return ret;
1982 }
1983 EXPORT_SYMBOL(sdw_handle_slave_status);
1984 
1985 void sdw_clear_slave_status(struct sdw_bus *bus, u32 request)
1986 {
1987 	struct sdw_slave *slave;
1988 	int i;
1989 
1990 	/* Check all non-zero devices */
1991 	for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1992 		mutex_lock(&bus->bus_lock);
1993 		if (test_bit(i, bus->assigned) == false) {
1994 			mutex_unlock(&bus->bus_lock);
1995 			continue;
1996 		}
1997 		mutex_unlock(&bus->bus_lock);
1998 
1999 		slave = sdw_get_slave(bus, i);
2000 		if (!slave)
2001 			continue;
2002 
2003 		if (slave->status != SDW_SLAVE_UNATTACHED) {
2004 			sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
2005 			slave->first_interrupt_done = false;
2006 			sdw_update_slave_status(slave, SDW_SLAVE_UNATTACHED);
2007 		}
2008 
2009 		/* keep track of request, used in pm_runtime resume */
2010 		slave->unattach_request = request;
2011 	}
2012 }
2013 EXPORT_SYMBOL(sdw_clear_slave_status);
2014