xref: /linux/drivers/soundwire/bus.c (revision 38fe0e0156c037c060f81fe4e36549fae760322d)
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 "bus.h"
11 #include "sysfs_local.h"
12 
13 static DEFINE_IDA(sdw_ida);
14 
15 static int sdw_get_id(struct sdw_bus *bus)
16 {
17 	int rc = ida_alloc(&sdw_ida, GFP_KERNEL);
18 
19 	if (rc < 0)
20 		return rc;
21 
22 	bus->id = rc;
23 	return 0;
24 }
25 
26 /**
27  * sdw_bus_master_add() - add a bus Master instance
28  * @bus: bus instance
29  * @parent: parent device
30  * @fwnode: firmware node handle
31  *
32  * Initializes the bus instance, read properties and create child
33  * devices.
34  */
35 int sdw_bus_master_add(struct sdw_bus *bus, struct device *parent,
36 		       struct fwnode_handle *fwnode)
37 {
38 	struct sdw_master_prop *prop = NULL;
39 	int ret;
40 
41 	if (!parent) {
42 		pr_err("SoundWire parent device is not set\n");
43 		return -ENODEV;
44 	}
45 
46 	ret = sdw_get_id(bus);
47 	if (ret < 0) {
48 		dev_err(parent, "Failed to get bus id\n");
49 		return ret;
50 	}
51 
52 	ret = sdw_master_device_add(bus, parent, fwnode);
53 	if (ret < 0) {
54 		dev_err(parent, "Failed to add master device at link %d\n",
55 			bus->link_id);
56 		return ret;
57 	}
58 
59 	if (!bus->ops) {
60 		dev_err(bus->dev, "SoundWire Bus ops are not set\n");
61 		return -EINVAL;
62 	}
63 
64 	if (!bus->compute_params) {
65 		dev_err(bus->dev,
66 			"Bandwidth allocation not configured, compute_params no set\n");
67 		return -EINVAL;
68 	}
69 
70 	mutex_init(&bus->msg_lock);
71 	mutex_init(&bus->bus_lock);
72 	INIT_LIST_HEAD(&bus->slaves);
73 	INIT_LIST_HEAD(&bus->m_rt_list);
74 
75 	/*
76 	 * Initialize multi_link flag
77 	 * TODO: populate this flag by reading property from FW node
78 	 */
79 	bus->multi_link = false;
80 	if (bus->ops->read_prop) {
81 		ret = bus->ops->read_prop(bus);
82 		if (ret < 0) {
83 			dev_err(bus->dev,
84 				"Bus read properties failed:%d\n", ret);
85 			return ret;
86 		}
87 	}
88 
89 	sdw_bus_debugfs_init(bus);
90 
91 	/*
92 	 * Device numbers in SoundWire are 0 through 15. Enumeration device
93 	 * number (0), Broadcast device number (15), Group numbers (12 and
94 	 * 13) and Master device number (14) are not used for assignment so
95 	 * mask these and other higher bits.
96 	 */
97 
98 	/* Set higher order bits */
99 	*bus->assigned = ~GENMASK(SDW_BROADCAST_DEV_NUM, SDW_ENUM_DEV_NUM);
100 
101 	/* Set enumuration device number and broadcast device number */
102 	set_bit(SDW_ENUM_DEV_NUM, bus->assigned);
103 	set_bit(SDW_BROADCAST_DEV_NUM, bus->assigned);
104 
105 	/* Set group device numbers and master device number */
106 	set_bit(SDW_GROUP12_DEV_NUM, bus->assigned);
107 	set_bit(SDW_GROUP13_DEV_NUM, bus->assigned);
108 	set_bit(SDW_MASTER_DEV_NUM, bus->assigned);
109 
110 	/*
111 	 * SDW is an enumerable bus, but devices can be powered off. So,
112 	 * they won't be able to report as present.
113 	 *
114 	 * Create Slave devices based on Slaves described in
115 	 * the respective firmware (ACPI/DT)
116 	 */
117 	if (IS_ENABLED(CONFIG_ACPI) && ACPI_HANDLE(bus->dev))
118 		ret = sdw_acpi_find_slaves(bus);
119 	else if (IS_ENABLED(CONFIG_OF) && bus->dev->of_node)
120 		ret = sdw_of_find_slaves(bus);
121 	else
122 		ret = -ENOTSUPP; /* No ACPI/DT so error out */
123 
124 	if (ret < 0) {
125 		dev_err(bus->dev, "Finding slaves failed:%d\n", ret);
126 		return ret;
127 	}
128 
129 	/*
130 	 * Initialize clock values based on Master properties. The max
131 	 * frequency is read from max_clk_freq property. Current assumption
132 	 * is that the bus will start at highest clock frequency when
133 	 * powered on.
134 	 *
135 	 * Default active bank will be 0 as out of reset the Slaves have
136 	 * to start with bank 0 (Table 40 of Spec)
137 	 */
138 	prop = &bus->prop;
139 	bus->params.max_dr_freq = prop->max_clk_freq * SDW_DOUBLE_RATE_FACTOR;
140 	bus->params.curr_dr_freq = bus->params.max_dr_freq;
141 	bus->params.curr_bank = SDW_BANK0;
142 	bus->params.next_bank = SDW_BANK1;
143 
144 	return 0;
145 }
146 EXPORT_SYMBOL(sdw_bus_master_add);
147 
148 static int sdw_delete_slave(struct device *dev, void *data)
149 {
150 	struct sdw_slave *slave = dev_to_sdw_dev(dev);
151 	struct sdw_bus *bus = slave->bus;
152 
153 	pm_runtime_disable(dev);
154 
155 	sdw_slave_debugfs_exit(slave);
156 
157 	mutex_lock(&bus->bus_lock);
158 
159 	if (slave->dev_num) /* clear dev_num if assigned */
160 		clear_bit(slave->dev_num, bus->assigned);
161 
162 	list_del_init(&slave->node);
163 	mutex_unlock(&bus->bus_lock);
164 
165 	device_unregister(dev);
166 	return 0;
167 }
168 
169 /**
170  * sdw_bus_master_delete() - delete the bus master instance
171  * @bus: bus to be deleted
172  *
173  * Remove the instance, delete the child devices.
174  */
175 void sdw_bus_master_delete(struct sdw_bus *bus)
176 {
177 	device_for_each_child(bus->dev, NULL, sdw_delete_slave);
178 	sdw_master_device_del(bus);
179 
180 	sdw_bus_debugfs_exit(bus);
181 	ida_free(&sdw_ida, bus->id);
182 }
183 EXPORT_SYMBOL(sdw_bus_master_delete);
184 
185 /*
186  * SDW IO Calls
187  */
188 
189 static inline int find_response_code(enum sdw_command_response resp)
190 {
191 	switch (resp) {
192 	case SDW_CMD_OK:
193 		return 0;
194 
195 	case SDW_CMD_IGNORED:
196 		return -ENODATA;
197 
198 	case SDW_CMD_TIMEOUT:
199 		return -ETIMEDOUT;
200 
201 	default:
202 		return -EIO;
203 	}
204 }
205 
206 static inline int do_transfer(struct sdw_bus *bus, struct sdw_msg *msg)
207 {
208 	int retry = bus->prop.err_threshold;
209 	enum sdw_command_response resp;
210 	int ret = 0, i;
211 
212 	for (i = 0; i <= retry; i++) {
213 		resp = bus->ops->xfer_msg(bus, msg);
214 		ret = find_response_code(resp);
215 
216 		/* if cmd is ok or ignored return */
217 		if (ret == 0 || ret == -ENODATA)
218 			return ret;
219 	}
220 
221 	return ret;
222 }
223 
224 static inline int do_transfer_defer(struct sdw_bus *bus,
225 				    struct sdw_msg *msg,
226 				    struct sdw_defer *defer)
227 {
228 	int retry = bus->prop.err_threshold;
229 	enum sdw_command_response resp;
230 	int ret = 0, i;
231 
232 	defer->msg = msg;
233 	defer->length = msg->len;
234 	init_completion(&defer->complete);
235 
236 	for (i = 0; i <= retry; i++) {
237 		resp = bus->ops->xfer_msg_defer(bus, msg, defer);
238 		ret = find_response_code(resp);
239 		/* if cmd is ok or ignored return */
240 		if (ret == 0 || ret == -ENODATA)
241 			return ret;
242 	}
243 
244 	return ret;
245 }
246 
247 static int sdw_reset_page(struct sdw_bus *bus, u16 dev_num)
248 {
249 	int retry = bus->prop.err_threshold;
250 	enum sdw_command_response resp;
251 	int ret = 0, i;
252 
253 	for (i = 0; i <= retry; i++) {
254 		resp = bus->ops->reset_page_addr(bus, dev_num);
255 		ret = find_response_code(resp);
256 		/* if cmd is ok or ignored return */
257 		if (ret == 0 || ret == -ENODATA)
258 			return ret;
259 	}
260 
261 	return ret;
262 }
263 
264 static int sdw_transfer_unlocked(struct sdw_bus *bus, struct sdw_msg *msg)
265 {
266 	int ret;
267 
268 	ret = do_transfer(bus, msg);
269 	if (ret != 0 && ret != -ENODATA)
270 		dev_err(bus->dev, "trf on Slave %d failed:%d %s addr %x count %d\n",
271 			msg->dev_num, ret,
272 			(msg->flags & SDW_MSG_FLAG_WRITE) ? "write" : "read",
273 			msg->addr, msg->len);
274 
275 	if (msg->page)
276 		sdw_reset_page(bus, msg->dev_num);
277 
278 	return ret;
279 }
280 
281 /**
282  * sdw_transfer() - Synchronous transfer message to a SDW Slave device
283  * @bus: SDW bus
284  * @msg: SDW message to be xfered
285  */
286 int sdw_transfer(struct sdw_bus *bus, struct sdw_msg *msg)
287 {
288 	int ret;
289 
290 	mutex_lock(&bus->msg_lock);
291 
292 	ret = sdw_transfer_unlocked(bus, msg);
293 
294 	mutex_unlock(&bus->msg_lock);
295 
296 	return ret;
297 }
298 
299 /**
300  * sdw_transfer_defer() - Asynchronously transfer message to a SDW Slave device
301  * @bus: SDW bus
302  * @msg: SDW message to be xfered
303  * @defer: Defer block for signal completion
304  *
305  * Caller needs to hold the msg_lock lock while calling this
306  */
307 int sdw_transfer_defer(struct sdw_bus *bus, struct sdw_msg *msg,
308 		       struct sdw_defer *defer)
309 {
310 	int ret;
311 
312 	if (!bus->ops->xfer_msg_defer)
313 		return -ENOTSUPP;
314 
315 	ret = do_transfer_defer(bus, msg, defer);
316 	if (ret != 0 && ret != -ENODATA)
317 		dev_err(bus->dev, "Defer trf on Slave %d failed:%d\n",
318 			msg->dev_num, ret);
319 
320 	if (msg->page)
321 		sdw_reset_page(bus, msg->dev_num);
322 
323 	return ret;
324 }
325 
326 int sdw_fill_msg(struct sdw_msg *msg, struct sdw_slave *slave,
327 		 u32 addr, size_t count, u16 dev_num, u8 flags, u8 *buf)
328 {
329 	memset(msg, 0, sizeof(*msg));
330 	msg->addr = addr; /* addr is 16 bit and truncated here */
331 	msg->len = count;
332 	msg->dev_num = dev_num;
333 	msg->flags = flags;
334 	msg->buf = buf;
335 
336 	if (addr < SDW_REG_NO_PAGE) /* no paging area */
337 		return 0;
338 
339 	if (addr >= SDW_REG_MAX) { /* illegal addr */
340 		pr_err("SDW: Invalid address %x passed\n", addr);
341 		return -EINVAL;
342 	}
343 
344 	if (addr < SDW_REG_OPTIONAL_PAGE) { /* 32k but no page */
345 		if (slave && !slave->prop.paging_support)
346 			return 0;
347 		/* no need for else as that will fall-through to paging */
348 	}
349 
350 	/* paging mandatory */
351 	if (dev_num == SDW_ENUM_DEV_NUM || dev_num == SDW_BROADCAST_DEV_NUM) {
352 		pr_err("SDW: Invalid device for paging :%d\n", dev_num);
353 		return -EINVAL;
354 	}
355 
356 	if (!slave) {
357 		pr_err("SDW: No slave for paging addr\n");
358 		return -EINVAL;
359 	}
360 
361 	if (!slave->prop.paging_support) {
362 		dev_err(&slave->dev,
363 			"address %x needs paging but no support\n", addr);
364 		return -EINVAL;
365 	}
366 
367 	msg->addr_page1 = FIELD_GET(SDW_SCP_ADDRPAGE1_MASK, addr);
368 	msg->addr_page2 = FIELD_GET(SDW_SCP_ADDRPAGE2_MASK, addr);
369 	msg->addr |= BIT(15);
370 	msg->page = true;
371 
372 	return 0;
373 }
374 
375 /*
376  * Read/Write IO functions.
377  * no_pm versions can only be called by the bus, e.g. while enumerating or
378  * handling suspend-resume sequences.
379  * all clients need to use the pm versions
380  */
381 
382 static int
383 sdw_nread_no_pm(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
384 {
385 	struct sdw_msg msg;
386 	int ret;
387 
388 	ret = sdw_fill_msg(&msg, slave, addr, count,
389 			   slave->dev_num, SDW_MSG_FLAG_READ, val);
390 	if (ret < 0)
391 		return ret;
392 
393 	return sdw_transfer(slave->bus, &msg);
394 }
395 
396 static int
397 sdw_nwrite_no_pm(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
398 {
399 	struct sdw_msg msg;
400 	int ret;
401 
402 	ret = sdw_fill_msg(&msg, slave, addr, count,
403 			   slave->dev_num, SDW_MSG_FLAG_WRITE, val);
404 	if (ret < 0)
405 		return ret;
406 
407 	return sdw_transfer(slave->bus, &msg);
408 }
409 
410 int sdw_write_no_pm(struct sdw_slave *slave, u32 addr, u8 value)
411 {
412 	return sdw_nwrite_no_pm(slave, addr, 1, &value);
413 }
414 EXPORT_SYMBOL(sdw_write_no_pm);
415 
416 static int
417 sdw_bread_no_pm(struct sdw_bus *bus, u16 dev_num, u32 addr)
418 {
419 	struct sdw_msg msg;
420 	u8 buf;
421 	int ret;
422 
423 	ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
424 			   SDW_MSG_FLAG_READ, &buf);
425 	if (ret < 0)
426 		return ret;
427 
428 	ret = sdw_transfer(bus, &msg);
429 	if (ret < 0)
430 		return ret;
431 
432 	return buf;
433 }
434 
435 static int
436 sdw_bwrite_no_pm(struct sdw_bus *bus, u16 dev_num, u32 addr, u8 value)
437 {
438 	struct sdw_msg msg;
439 	int ret;
440 
441 	ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
442 			   SDW_MSG_FLAG_WRITE, &value);
443 	if (ret < 0)
444 		return ret;
445 
446 	return sdw_transfer(bus, &msg);
447 }
448 
449 int sdw_bread_no_pm_unlocked(struct sdw_bus *bus, u16 dev_num, u32 addr)
450 {
451 	struct sdw_msg msg;
452 	u8 buf;
453 	int ret;
454 
455 	ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
456 			   SDW_MSG_FLAG_READ, &buf);
457 	if (ret < 0)
458 		return ret;
459 
460 	ret = sdw_transfer_unlocked(bus, &msg);
461 	if (ret < 0)
462 		return ret;
463 
464 	return buf;
465 }
466 EXPORT_SYMBOL(sdw_bread_no_pm_unlocked);
467 
468 int sdw_bwrite_no_pm_unlocked(struct sdw_bus *bus, u16 dev_num, u32 addr, u8 value)
469 {
470 	struct sdw_msg msg;
471 	int ret;
472 
473 	ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
474 			   SDW_MSG_FLAG_WRITE, &value);
475 	if (ret < 0)
476 		return ret;
477 
478 	return sdw_transfer_unlocked(bus, &msg);
479 }
480 EXPORT_SYMBOL(sdw_bwrite_no_pm_unlocked);
481 
482 int sdw_read_no_pm(struct sdw_slave *slave, u32 addr)
483 {
484 	u8 buf;
485 	int ret;
486 
487 	ret = sdw_nread_no_pm(slave, addr, 1, &buf);
488 	if (ret < 0)
489 		return ret;
490 	else
491 		return buf;
492 }
493 EXPORT_SYMBOL(sdw_read_no_pm);
494 
495 int sdw_update_no_pm(struct sdw_slave *slave, u32 addr, u8 mask, u8 val)
496 {
497 	int tmp;
498 
499 	tmp = sdw_read_no_pm(slave, addr);
500 	if (tmp < 0)
501 		return tmp;
502 
503 	tmp = (tmp & ~mask) | val;
504 	return sdw_write_no_pm(slave, addr, tmp);
505 }
506 EXPORT_SYMBOL(sdw_update_no_pm);
507 
508 /* Read-Modify-Write Slave register */
509 int sdw_update(struct sdw_slave *slave, u32 addr, u8 mask, u8 val)
510 {
511 	int tmp;
512 
513 	tmp = sdw_read(slave, addr);
514 	if (tmp < 0)
515 		return tmp;
516 
517 	tmp = (tmp & ~mask) | val;
518 	return sdw_write(slave, addr, tmp);
519 }
520 EXPORT_SYMBOL(sdw_update);
521 
522 /**
523  * sdw_nread() - Read "n" contiguous SDW Slave registers
524  * @slave: SDW Slave
525  * @addr: Register address
526  * @count: length
527  * @val: Buffer for values to be read
528  */
529 int sdw_nread(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
530 {
531 	int ret;
532 
533 	ret = pm_runtime_get_sync(&slave->dev);
534 	if (ret < 0 && ret != -EACCES) {
535 		pm_runtime_put_noidle(&slave->dev);
536 		return ret;
537 	}
538 
539 	ret = sdw_nread_no_pm(slave, addr, count, val);
540 
541 	pm_runtime_mark_last_busy(&slave->dev);
542 	pm_runtime_put(&slave->dev);
543 
544 	return ret;
545 }
546 EXPORT_SYMBOL(sdw_nread);
547 
548 /**
549  * sdw_nwrite() - Write "n" contiguous SDW Slave registers
550  * @slave: SDW Slave
551  * @addr: Register address
552  * @count: length
553  * @val: Buffer for values to be read
554  */
555 int sdw_nwrite(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
556 {
557 	int ret;
558 
559 	ret = pm_runtime_get_sync(&slave->dev);
560 	if (ret < 0 && ret != -EACCES) {
561 		pm_runtime_put_noidle(&slave->dev);
562 		return ret;
563 	}
564 
565 	ret = sdw_nwrite_no_pm(slave, addr, count, val);
566 
567 	pm_runtime_mark_last_busy(&slave->dev);
568 	pm_runtime_put(&slave->dev);
569 
570 	return ret;
571 }
572 EXPORT_SYMBOL(sdw_nwrite);
573 
574 /**
575  * sdw_read() - Read a SDW Slave register
576  * @slave: SDW Slave
577  * @addr: Register address
578  */
579 int sdw_read(struct sdw_slave *slave, u32 addr)
580 {
581 	u8 buf;
582 	int ret;
583 
584 	ret = sdw_nread(slave, addr, 1, &buf);
585 	if (ret < 0)
586 		return ret;
587 
588 	return buf;
589 }
590 EXPORT_SYMBOL(sdw_read);
591 
592 /**
593  * sdw_write() - Write a SDW Slave register
594  * @slave: SDW Slave
595  * @addr: Register address
596  * @value: Register value
597  */
598 int sdw_write(struct sdw_slave *slave, u32 addr, u8 value)
599 {
600 	return sdw_nwrite(slave, addr, 1, &value);
601 }
602 EXPORT_SYMBOL(sdw_write);
603 
604 /*
605  * SDW alert handling
606  */
607 
608 /* called with bus_lock held */
609 static struct sdw_slave *sdw_get_slave(struct sdw_bus *bus, int i)
610 {
611 	struct sdw_slave *slave;
612 
613 	list_for_each_entry(slave, &bus->slaves, node) {
614 		if (slave->dev_num == i)
615 			return slave;
616 	}
617 
618 	return NULL;
619 }
620 
621 int sdw_compare_devid(struct sdw_slave *slave, struct sdw_slave_id id)
622 {
623 	if (slave->id.mfg_id != id.mfg_id ||
624 	    slave->id.part_id != id.part_id ||
625 	    slave->id.class_id != id.class_id ||
626 	    (slave->id.unique_id != SDW_IGNORED_UNIQUE_ID &&
627 	     slave->id.unique_id != id.unique_id))
628 		return -ENODEV;
629 
630 	return 0;
631 }
632 EXPORT_SYMBOL(sdw_compare_devid);
633 
634 /* called with bus_lock held */
635 static int sdw_get_device_num(struct sdw_slave *slave)
636 {
637 	int bit;
638 
639 	bit = find_first_zero_bit(slave->bus->assigned, SDW_MAX_DEVICES);
640 	if (bit == SDW_MAX_DEVICES) {
641 		bit = -ENODEV;
642 		goto err;
643 	}
644 
645 	/*
646 	 * Do not update dev_num in Slave data structure here,
647 	 * Update once program dev_num is successful
648 	 */
649 	set_bit(bit, slave->bus->assigned);
650 
651 err:
652 	return bit;
653 }
654 
655 static int sdw_assign_device_num(struct sdw_slave *slave)
656 {
657 	struct sdw_bus *bus = slave->bus;
658 	int ret, dev_num;
659 	bool new_device = false;
660 
661 	/* check first if device number is assigned, if so reuse that */
662 	if (!slave->dev_num) {
663 		if (!slave->dev_num_sticky) {
664 			mutex_lock(&slave->bus->bus_lock);
665 			dev_num = sdw_get_device_num(slave);
666 			mutex_unlock(&slave->bus->bus_lock);
667 			if (dev_num < 0) {
668 				dev_err(bus->dev, "Get dev_num failed: %d\n",
669 					dev_num);
670 				return dev_num;
671 			}
672 			slave->dev_num = dev_num;
673 			slave->dev_num_sticky = dev_num;
674 			new_device = true;
675 		} else {
676 			slave->dev_num = slave->dev_num_sticky;
677 		}
678 	}
679 
680 	if (!new_device)
681 		dev_dbg(bus->dev,
682 			"Slave already registered, reusing dev_num:%d\n",
683 			slave->dev_num);
684 
685 	/* Clear the slave->dev_num to transfer message on device 0 */
686 	dev_num = slave->dev_num;
687 	slave->dev_num = 0;
688 
689 	ret = sdw_write_no_pm(slave, SDW_SCP_DEVNUMBER, dev_num);
690 	if (ret < 0) {
691 		dev_err(bus->dev, "Program device_num %d failed: %d\n",
692 			dev_num, ret);
693 		return ret;
694 	}
695 
696 	/* After xfer of msg, restore dev_num */
697 	slave->dev_num = slave->dev_num_sticky;
698 
699 	return 0;
700 }
701 
702 void sdw_extract_slave_id(struct sdw_bus *bus,
703 			  u64 addr, struct sdw_slave_id *id)
704 {
705 	dev_dbg(bus->dev, "SDW Slave Addr: %llx\n", addr);
706 
707 	id->sdw_version = SDW_VERSION(addr);
708 	id->unique_id = SDW_UNIQUE_ID(addr);
709 	id->mfg_id = SDW_MFG_ID(addr);
710 	id->part_id = SDW_PART_ID(addr);
711 	id->class_id = SDW_CLASS_ID(addr);
712 
713 	dev_dbg(bus->dev,
714 		"SDW Slave class_id 0x%02x, mfg_id 0x%04x, part_id 0x%04x, unique_id 0x%x, version 0x%x\n",
715 		id->class_id, id->mfg_id, id->part_id, id->unique_id, id->sdw_version);
716 }
717 EXPORT_SYMBOL(sdw_extract_slave_id);
718 
719 static int sdw_program_device_num(struct sdw_bus *bus)
720 {
721 	u8 buf[SDW_NUM_DEV_ID_REGISTERS] = {0};
722 	struct sdw_slave *slave, *_s;
723 	struct sdw_slave_id id;
724 	struct sdw_msg msg;
725 	bool found;
726 	int count = 0, ret;
727 	u64 addr;
728 
729 	/* No Slave, so use raw xfer api */
730 	ret = sdw_fill_msg(&msg, NULL, SDW_SCP_DEVID_0,
731 			   SDW_NUM_DEV_ID_REGISTERS, 0, SDW_MSG_FLAG_READ, buf);
732 	if (ret < 0)
733 		return ret;
734 
735 	do {
736 		ret = sdw_transfer(bus, &msg);
737 		if (ret == -ENODATA) { /* end of device id reads */
738 			dev_dbg(bus->dev, "No more devices to enumerate\n");
739 			ret = 0;
740 			break;
741 		}
742 		if (ret < 0) {
743 			dev_err(bus->dev, "DEVID read fail:%d\n", ret);
744 			break;
745 		}
746 
747 		/*
748 		 * Construct the addr and extract. Cast the higher shift
749 		 * bits to avoid truncation due to size limit.
750 		 */
751 		addr = buf[5] | (buf[4] << 8) | (buf[3] << 16) |
752 			((u64)buf[2] << 24) | ((u64)buf[1] << 32) |
753 			((u64)buf[0] << 40);
754 
755 		sdw_extract_slave_id(bus, addr, &id);
756 
757 		found = false;
758 		/* Now compare with entries */
759 		list_for_each_entry_safe(slave, _s, &bus->slaves, node) {
760 			if (sdw_compare_devid(slave, id) == 0) {
761 				found = true;
762 
763 				/*
764 				 * Assign a new dev_num to this Slave and
765 				 * not mark it present. It will be marked
766 				 * present after it reports ATTACHED on new
767 				 * dev_num
768 				 */
769 				ret = sdw_assign_device_num(slave);
770 				if (ret < 0) {
771 					dev_err(bus->dev,
772 						"Assign dev_num failed:%d\n",
773 						ret);
774 					return ret;
775 				}
776 
777 				break;
778 			}
779 		}
780 
781 		if (!found) {
782 			/* TODO: Park this device in Group 13 */
783 
784 			/*
785 			 * add Slave device even if there is no platform
786 			 * firmware description. There will be no driver probe
787 			 * but the user/integration will be able to see the
788 			 * device, enumeration status and device number in sysfs
789 			 */
790 			sdw_slave_add(bus, &id, NULL);
791 
792 			dev_err(bus->dev, "Slave Entry not found\n");
793 		}
794 
795 		count++;
796 
797 		/*
798 		 * Check till error out or retry (count) exhausts.
799 		 * Device can drop off and rejoin during enumeration
800 		 * so count till twice the bound.
801 		 */
802 
803 	} while (ret == 0 && count < (SDW_MAX_DEVICES * 2));
804 
805 	return ret;
806 }
807 
808 static void sdw_modify_slave_status(struct sdw_slave *slave,
809 				    enum sdw_slave_status status)
810 {
811 	struct sdw_bus *bus = slave->bus;
812 
813 	mutex_lock(&bus->bus_lock);
814 
815 	dev_vdbg(bus->dev,
816 		 "%s: changing status slave %d status %d new status %d\n",
817 		 __func__, slave->dev_num, slave->status, status);
818 
819 	if (status == SDW_SLAVE_UNATTACHED) {
820 		dev_dbg(&slave->dev,
821 			"%s: initializing enumeration and init completion for Slave %d\n",
822 			__func__, slave->dev_num);
823 
824 		init_completion(&slave->enumeration_complete);
825 		init_completion(&slave->initialization_complete);
826 
827 	} else if ((status == SDW_SLAVE_ATTACHED) &&
828 		   (slave->status == SDW_SLAVE_UNATTACHED)) {
829 		dev_dbg(&slave->dev,
830 			"%s: signaling enumeration completion for Slave %d\n",
831 			__func__, slave->dev_num);
832 
833 		complete(&slave->enumeration_complete);
834 	}
835 	slave->status = status;
836 	mutex_unlock(&bus->bus_lock);
837 }
838 
839 static enum sdw_clk_stop_mode sdw_get_clk_stop_mode(struct sdw_slave *slave)
840 {
841 	enum sdw_clk_stop_mode mode;
842 
843 	/*
844 	 * Query for clock stop mode if Slave implements
845 	 * ops->get_clk_stop_mode, else read from property.
846 	 */
847 	if (slave->ops && slave->ops->get_clk_stop_mode) {
848 		mode = slave->ops->get_clk_stop_mode(slave);
849 	} else {
850 		if (slave->prop.clk_stop_mode1)
851 			mode = SDW_CLK_STOP_MODE1;
852 		else
853 			mode = SDW_CLK_STOP_MODE0;
854 	}
855 
856 	return mode;
857 }
858 
859 static int sdw_slave_clk_stop_callback(struct sdw_slave *slave,
860 				       enum sdw_clk_stop_mode mode,
861 				       enum sdw_clk_stop_type type)
862 {
863 	int ret;
864 
865 	if (slave->ops && slave->ops->clk_stop) {
866 		ret = slave->ops->clk_stop(slave, mode, type);
867 		if (ret < 0) {
868 			dev_err(&slave->dev,
869 				"Clk Stop type =%d failed: %d\n", type, ret);
870 			return ret;
871 		}
872 	}
873 
874 	return 0;
875 }
876 
877 static int sdw_slave_clk_stop_prepare(struct sdw_slave *slave,
878 				      enum sdw_clk_stop_mode mode,
879 				      bool prepare)
880 {
881 	bool wake_en;
882 	u32 val = 0;
883 	int ret;
884 
885 	wake_en = slave->prop.wake_capable;
886 
887 	if (prepare) {
888 		val = SDW_SCP_SYSTEMCTRL_CLK_STP_PREP;
889 
890 		if (mode == SDW_CLK_STOP_MODE1)
891 			val |= SDW_SCP_SYSTEMCTRL_CLK_STP_MODE1;
892 
893 		if (wake_en)
894 			val |= SDW_SCP_SYSTEMCTRL_WAKE_UP_EN;
895 	} else {
896 		ret = sdw_read_no_pm(slave, SDW_SCP_SYSTEMCTRL);
897 		if (ret < 0) {
898 			dev_err(&slave->dev, "SDW_SCP_SYSTEMCTRL read failed:%d\n", ret);
899 			return ret;
900 		}
901 		val = ret;
902 		val &= ~(SDW_SCP_SYSTEMCTRL_CLK_STP_PREP);
903 	}
904 
905 	ret = sdw_write_no_pm(slave, SDW_SCP_SYSTEMCTRL, val);
906 
907 	if (ret < 0)
908 		dev_err(&slave->dev,
909 			"Clock Stop prepare failed for slave: %d", ret);
910 
911 	return ret;
912 }
913 
914 static int sdw_bus_wait_for_clk_prep_deprep(struct sdw_bus *bus, u16 dev_num)
915 {
916 	int retry = bus->clk_stop_timeout;
917 	int val;
918 
919 	do {
920 		val = sdw_bread_no_pm(bus, dev_num, SDW_SCP_STAT);
921 		if (val < 0) {
922 			dev_err(bus->dev, "SDW_SCP_STAT bread failed:%d\n", val);
923 			return val;
924 		}
925 		val &= SDW_SCP_STAT_CLK_STP_NF;
926 		if (!val) {
927 			dev_dbg(bus->dev, "clock stop prep/de-prep done slave:%d",
928 				dev_num);
929 			return 0;
930 		}
931 
932 		usleep_range(1000, 1500);
933 		retry--;
934 	} while (retry);
935 
936 	dev_err(bus->dev, "clock stop prep/de-prep failed slave:%d",
937 		dev_num);
938 
939 	return -ETIMEDOUT;
940 }
941 
942 /**
943  * sdw_bus_prep_clk_stop: prepare Slave(s) for clock stop
944  *
945  * @bus: SDW bus instance
946  *
947  * Query Slave for clock stop mode and prepare for that mode.
948  */
949 int sdw_bus_prep_clk_stop(struct sdw_bus *bus)
950 {
951 	enum sdw_clk_stop_mode slave_mode;
952 	bool simple_clk_stop = true;
953 	struct sdw_slave *slave;
954 	bool is_slave = false;
955 	int ret = 0;
956 
957 	/*
958 	 * In order to save on transition time, prepare
959 	 * each Slave and then wait for all Slave(s) to be
960 	 * prepared for clock stop.
961 	 */
962 	list_for_each_entry(slave, &bus->slaves, node) {
963 		if (!slave->dev_num)
964 			continue;
965 
966 		if (slave->status != SDW_SLAVE_ATTACHED &&
967 		    slave->status != SDW_SLAVE_ALERT)
968 			continue;
969 
970 		/* Identify if Slave(s) are available on Bus */
971 		is_slave = true;
972 
973 		slave_mode = sdw_get_clk_stop_mode(slave);
974 		slave->curr_clk_stop_mode = slave_mode;
975 
976 		ret = sdw_slave_clk_stop_callback(slave, slave_mode,
977 						  SDW_CLK_PRE_PREPARE);
978 		if (ret < 0) {
979 			dev_err(&slave->dev,
980 				"pre-prepare failed:%d", ret);
981 			return ret;
982 		}
983 
984 		ret = sdw_slave_clk_stop_prepare(slave,
985 						 slave_mode, true);
986 		if (ret < 0) {
987 			dev_err(&slave->dev,
988 				"pre-prepare failed:%d", ret);
989 			return ret;
990 		}
991 
992 		if (slave_mode == SDW_CLK_STOP_MODE1)
993 			simple_clk_stop = false;
994 	}
995 
996 	/* Skip remaining clock stop preparation if no Slave is attached */
997 	if (!is_slave)
998 		return ret;
999 
1000 	if (!simple_clk_stop) {
1001 		ret = sdw_bus_wait_for_clk_prep_deprep(bus,
1002 						       SDW_BROADCAST_DEV_NUM);
1003 		if (ret < 0)
1004 			return ret;
1005 	}
1006 
1007 	/* Inform slaves that prep is done */
1008 	list_for_each_entry(slave, &bus->slaves, node) {
1009 		if (!slave->dev_num)
1010 			continue;
1011 
1012 		if (slave->status != SDW_SLAVE_ATTACHED &&
1013 		    slave->status != SDW_SLAVE_ALERT)
1014 			continue;
1015 
1016 		slave_mode = slave->curr_clk_stop_mode;
1017 
1018 		if (slave_mode == SDW_CLK_STOP_MODE1) {
1019 			ret = sdw_slave_clk_stop_callback(slave,
1020 							  slave_mode,
1021 							  SDW_CLK_POST_PREPARE);
1022 
1023 			if (ret < 0) {
1024 				dev_err(&slave->dev,
1025 					"post-prepare failed:%d", ret);
1026 			}
1027 		}
1028 	}
1029 
1030 	return ret;
1031 }
1032 EXPORT_SYMBOL(sdw_bus_prep_clk_stop);
1033 
1034 /**
1035  * sdw_bus_clk_stop: stop bus clock
1036  *
1037  * @bus: SDW bus instance
1038  *
1039  * After preparing the Slaves for clock stop, stop the clock by broadcasting
1040  * write to SCP_CTRL register.
1041  */
1042 int sdw_bus_clk_stop(struct sdw_bus *bus)
1043 {
1044 	int ret;
1045 
1046 	/*
1047 	 * broadcast clock stop now, attached Slaves will ACK this,
1048 	 * unattached will ignore
1049 	 */
1050 	ret = sdw_bwrite_no_pm(bus, SDW_BROADCAST_DEV_NUM,
1051 			       SDW_SCP_CTRL, SDW_SCP_CTRL_CLK_STP_NOW);
1052 	if (ret < 0) {
1053 		if (ret == -ENODATA)
1054 			dev_dbg(bus->dev,
1055 				"ClockStopNow Broadcast msg ignored %d", ret);
1056 		else
1057 			dev_err(bus->dev,
1058 				"ClockStopNow Broadcast msg failed %d", ret);
1059 		return ret;
1060 	}
1061 
1062 	return 0;
1063 }
1064 EXPORT_SYMBOL(sdw_bus_clk_stop);
1065 
1066 /**
1067  * sdw_bus_exit_clk_stop: Exit clock stop mode
1068  *
1069  * @bus: SDW bus instance
1070  *
1071  * This De-prepares the Slaves by exiting Clock Stop Mode 0. For the Slaves
1072  * exiting Clock Stop Mode 1, they will be de-prepared after they enumerate
1073  * back.
1074  */
1075 int sdw_bus_exit_clk_stop(struct sdw_bus *bus)
1076 {
1077 	enum sdw_clk_stop_mode mode;
1078 	bool simple_clk_stop = true;
1079 	struct sdw_slave *slave;
1080 	bool is_slave = false;
1081 	int ret;
1082 
1083 	/*
1084 	 * In order to save on transition time, de-prepare
1085 	 * each Slave and then wait for all Slave(s) to be
1086 	 * de-prepared after clock resume.
1087 	 */
1088 	list_for_each_entry(slave, &bus->slaves, node) {
1089 		if (!slave->dev_num)
1090 			continue;
1091 
1092 		if (slave->status != SDW_SLAVE_ATTACHED &&
1093 		    slave->status != SDW_SLAVE_ALERT)
1094 			continue;
1095 
1096 		/* Identify if Slave(s) are available on Bus */
1097 		is_slave = true;
1098 
1099 		mode = slave->curr_clk_stop_mode;
1100 
1101 		if (mode == SDW_CLK_STOP_MODE1) {
1102 			simple_clk_stop = false;
1103 			continue;
1104 		}
1105 
1106 		ret = sdw_slave_clk_stop_callback(slave, mode,
1107 						  SDW_CLK_PRE_DEPREPARE);
1108 		if (ret < 0)
1109 			dev_warn(&slave->dev,
1110 				 "clk stop deprep failed:%d", ret);
1111 
1112 		ret = sdw_slave_clk_stop_prepare(slave, mode,
1113 						 false);
1114 
1115 		if (ret < 0)
1116 			dev_warn(&slave->dev,
1117 				 "clk stop deprep failed:%d", ret);
1118 	}
1119 
1120 	/* Skip remaining clock stop de-preparation if no Slave is attached */
1121 	if (!is_slave)
1122 		return 0;
1123 
1124 	if (!simple_clk_stop)
1125 		sdw_bus_wait_for_clk_prep_deprep(bus, SDW_BROADCAST_DEV_NUM);
1126 
1127 	list_for_each_entry(slave, &bus->slaves, node) {
1128 		if (!slave->dev_num)
1129 			continue;
1130 
1131 		if (slave->status != SDW_SLAVE_ATTACHED &&
1132 		    slave->status != SDW_SLAVE_ALERT)
1133 			continue;
1134 
1135 		mode = slave->curr_clk_stop_mode;
1136 		sdw_slave_clk_stop_callback(slave, mode,
1137 					    SDW_CLK_POST_DEPREPARE);
1138 	}
1139 
1140 	return 0;
1141 }
1142 EXPORT_SYMBOL(sdw_bus_exit_clk_stop);
1143 
1144 int sdw_configure_dpn_intr(struct sdw_slave *slave,
1145 			   int port, bool enable, int mask)
1146 {
1147 	u32 addr;
1148 	int ret;
1149 	u8 val = 0;
1150 
1151 	if (slave->bus->params.s_data_mode != SDW_PORT_DATA_MODE_NORMAL) {
1152 		dev_dbg(&slave->dev, "TEST FAIL interrupt %s\n",
1153 			enable ? "on" : "off");
1154 		mask |= SDW_DPN_INT_TEST_FAIL;
1155 	}
1156 
1157 	addr = SDW_DPN_INTMASK(port);
1158 
1159 	/* Set/Clear port ready interrupt mask */
1160 	if (enable) {
1161 		val |= mask;
1162 		val |= SDW_DPN_INT_PORT_READY;
1163 	} else {
1164 		val &= ~(mask);
1165 		val &= ~SDW_DPN_INT_PORT_READY;
1166 	}
1167 
1168 	ret = sdw_update(slave, addr, (mask | SDW_DPN_INT_PORT_READY), val);
1169 	if (ret < 0)
1170 		dev_err(&slave->dev,
1171 			"SDW_DPN_INTMASK write failed:%d\n", val);
1172 
1173 	return ret;
1174 }
1175 
1176 static int sdw_slave_set_frequency(struct sdw_slave *slave)
1177 {
1178 	u32 mclk_freq = slave->bus->prop.mclk_freq;
1179 	u32 curr_freq = slave->bus->params.curr_dr_freq >> 1;
1180 	unsigned int scale;
1181 	u8 scale_index;
1182 	u8 base;
1183 	int ret;
1184 
1185 	/*
1186 	 * frequency base and scale registers are required for SDCA
1187 	 * devices. They may also be used for 1.2+/non-SDCA devices,
1188 	 * but we will need a DisCo property to cover this case
1189 	 */
1190 	if (!slave->id.class_id)
1191 		return 0;
1192 
1193 	if (!mclk_freq) {
1194 		dev_err(&slave->dev,
1195 			"no bus MCLK, cannot set SDW_SCP_BUS_CLOCK_BASE\n");
1196 		return -EINVAL;
1197 	}
1198 
1199 	/*
1200 	 * map base frequency using Table 89 of SoundWire 1.2 spec.
1201 	 * The order of the tests just follows the specification, this
1202 	 * is not a selection between possible values or a search for
1203 	 * the best value but just a mapping.  Only one case per platform
1204 	 * is relevant.
1205 	 * Some BIOS have inconsistent values for mclk_freq but a
1206 	 * correct root so we force the mclk_freq to avoid variations.
1207 	 */
1208 	if (!(19200000 % mclk_freq)) {
1209 		mclk_freq = 19200000;
1210 		base = SDW_SCP_BASE_CLOCK_19200000_HZ;
1211 	} else if (!(24000000 % mclk_freq)) {
1212 		mclk_freq = 24000000;
1213 		base = SDW_SCP_BASE_CLOCK_24000000_HZ;
1214 	} else if (!(24576000 % mclk_freq)) {
1215 		mclk_freq = 24576000;
1216 		base = SDW_SCP_BASE_CLOCK_24576000_HZ;
1217 	} else if (!(22579200 % mclk_freq)) {
1218 		mclk_freq = 22579200;
1219 		base = SDW_SCP_BASE_CLOCK_22579200_HZ;
1220 	} else if (!(32000000 % mclk_freq)) {
1221 		mclk_freq = 32000000;
1222 		base = SDW_SCP_BASE_CLOCK_32000000_HZ;
1223 	} else {
1224 		dev_err(&slave->dev,
1225 			"Unsupported clock base, mclk %d\n",
1226 			mclk_freq);
1227 		return -EINVAL;
1228 	}
1229 
1230 	if (mclk_freq % curr_freq) {
1231 		dev_err(&slave->dev,
1232 			"mclk %d is not multiple of bus curr_freq %d\n",
1233 			mclk_freq, curr_freq);
1234 		return -EINVAL;
1235 	}
1236 
1237 	scale = mclk_freq / curr_freq;
1238 
1239 	/*
1240 	 * map scale to Table 90 of SoundWire 1.2 spec - and check
1241 	 * that the scale is a power of two and maximum 64
1242 	 */
1243 	scale_index = ilog2(scale);
1244 
1245 	if (BIT(scale_index) != scale || scale_index > 6) {
1246 		dev_err(&slave->dev,
1247 			"No match found for scale %d, bus mclk %d curr_freq %d\n",
1248 			scale, mclk_freq, curr_freq);
1249 		return -EINVAL;
1250 	}
1251 	scale_index++;
1252 
1253 	ret = sdw_write_no_pm(slave, SDW_SCP_BUS_CLOCK_BASE, base);
1254 	if (ret < 0) {
1255 		dev_err(&slave->dev,
1256 			"SDW_SCP_BUS_CLOCK_BASE write failed:%d\n", ret);
1257 		return ret;
1258 	}
1259 
1260 	/* initialize scale for both banks */
1261 	ret = sdw_write_no_pm(slave, SDW_SCP_BUSCLOCK_SCALE_B0, scale_index);
1262 	if (ret < 0) {
1263 		dev_err(&slave->dev,
1264 			"SDW_SCP_BUSCLOCK_SCALE_B0 write failed:%d\n", ret);
1265 		return ret;
1266 	}
1267 	ret = sdw_write_no_pm(slave, SDW_SCP_BUSCLOCK_SCALE_B1, scale_index);
1268 	if (ret < 0)
1269 		dev_err(&slave->dev,
1270 			"SDW_SCP_BUSCLOCK_SCALE_B1 write failed:%d\n", ret);
1271 
1272 	dev_dbg(&slave->dev,
1273 		"Configured bus base %d, scale %d, mclk %d, curr_freq %d\n",
1274 		base, scale_index, mclk_freq, curr_freq);
1275 
1276 	return ret;
1277 }
1278 
1279 static int sdw_initialize_slave(struct sdw_slave *slave)
1280 {
1281 	struct sdw_slave_prop *prop = &slave->prop;
1282 	int status;
1283 	int ret;
1284 	u8 val;
1285 
1286 	ret = sdw_slave_set_frequency(slave);
1287 	if (ret < 0)
1288 		return ret;
1289 
1290 	if (slave->bus->prop.quirks & SDW_MASTER_QUIRKS_CLEAR_INITIAL_CLASH) {
1291 		/* Clear bus clash interrupt before enabling interrupt mask */
1292 		status = sdw_read_no_pm(slave, SDW_SCP_INT1);
1293 		if (status < 0) {
1294 			dev_err(&slave->dev,
1295 				"SDW_SCP_INT1 (BUS_CLASH) read failed:%d\n", status);
1296 			return status;
1297 		}
1298 		if (status & SDW_SCP_INT1_BUS_CLASH) {
1299 			dev_warn(&slave->dev, "Bus clash detected before INT mask is enabled\n");
1300 			ret = sdw_write_no_pm(slave, SDW_SCP_INT1, SDW_SCP_INT1_BUS_CLASH);
1301 			if (ret < 0) {
1302 				dev_err(&slave->dev,
1303 					"SDW_SCP_INT1 (BUS_CLASH) write failed:%d\n", ret);
1304 				return ret;
1305 			}
1306 		}
1307 	}
1308 	if ((slave->bus->prop.quirks & SDW_MASTER_QUIRKS_CLEAR_INITIAL_PARITY) &&
1309 	    !(slave->prop.quirks & SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY)) {
1310 		/* Clear parity interrupt before enabling interrupt mask */
1311 		status = sdw_read_no_pm(slave, SDW_SCP_INT1);
1312 		if (status < 0) {
1313 			dev_err(&slave->dev,
1314 				"SDW_SCP_INT1 (PARITY) read failed:%d\n", status);
1315 			return status;
1316 		}
1317 		if (status & SDW_SCP_INT1_PARITY) {
1318 			dev_warn(&slave->dev, "PARITY error detected before INT mask is enabled\n");
1319 			ret = sdw_write_no_pm(slave, SDW_SCP_INT1, SDW_SCP_INT1_PARITY);
1320 			if (ret < 0) {
1321 				dev_err(&slave->dev,
1322 					"SDW_SCP_INT1 (PARITY) write failed:%d\n", ret);
1323 				return ret;
1324 			}
1325 		}
1326 	}
1327 
1328 	/*
1329 	 * Set SCP_INT1_MASK register, typically bus clash and
1330 	 * implementation-defined interrupt mask. The Parity detection
1331 	 * may not always be correct on startup so its use is
1332 	 * device-dependent, it might e.g. only be enabled in
1333 	 * steady-state after a couple of frames.
1334 	 */
1335 	val = slave->prop.scp_int1_mask;
1336 
1337 	/* Enable SCP interrupts */
1338 	ret = sdw_update_no_pm(slave, SDW_SCP_INTMASK1, val, val);
1339 	if (ret < 0) {
1340 		dev_err(&slave->dev,
1341 			"SDW_SCP_INTMASK1 write failed:%d\n", ret);
1342 		return ret;
1343 	}
1344 
1345 	/* No need to continue if DP0 is not present */
1346 	if (!slave->prop.dp0_prop)
1347 		return 0;
1348 
1349 	/* Enable DP0 interrupts */
1350 	val = prop->dp0_prop->imp_def_interrupts;
1351 	val |= SDW_DP0_INT_PORT_READY | SDW_DP0_INT_BRA_FAILURE;
1352 
1353 	ret = sdw_update_no_pm(slave, SDW_DP0_INTMASK, val, val);
1354 	if (ret < 0)
1355 		dev_err(&slave->dev,
1356 			"SDW_DP0_INTMASK read failed:%d\n", ret);
1357 	return ret;
1358 }
1359 
1360 static int sdw_handle_dp0_interrupt(struct sdw_slave *slave, u8 *slave_status)
1361 {
1362 	u8 clear, impl_int_mask;
1363 	int status, status2, ret, count = 0;
1364 
1365 	status = sdw_read_no_pm(slave, SDW_DP0_INT);
1366 	if (status < 0) {
1367 		dev_err(&slave->dev,
1368 			"SDW_DP0_INT read failed:%d\n", status);
1369 		return status;
1370 	}
1371 
1372 	do {
1373 		clear = status & ~SDW_DP0_INTERRUPTS;
1374 
1375 		if (status & SDW_DP0_INT_TEST_FAIL) {
1376 			dev_err(&slave->dev, "Test fail for port 0\n");
1377 			clear |= SDW_DP0_INT_TEST_FAIL;
1378 		}
1379 
1380 		/*
1381 		 * Assumption: PORT_READY interrupt will be received only for
1382 		 * ports implementing Channel Prepare state machine (CP_SM)
1383 		 */
1384 
1385 		if (status & SDW_DP0_INT_PORT_READY) {
1386 			complete(&slave->port_ready[0]);
1387 			clear |= SDW_DP0_INT_PORT_READY;
1388 		}
1389 
1390 		if (status & SDW_DP0_INT_BRA_FAILURE) {
1391 			dev_err(&slave->dev, "BRA failed\n");
1392 			clear |= SDW_DP0_INT_BRA_FAILURE;
1393 		}
1394 
1395 		impl_int_mask = SDW_DP0_INT_IMPDEF1 |
1396 			SDW_DP0_INT_IMPDEF2 | SDW_DP0_INT_IMPDEF3;
1397 
1398 		if (status & impl_int_mask) {
1399 			clear |= impl_int_mask;
1400 			*slave_status = clear;
1401 		}
1402 
1403 		/* clear the interrupts but don't touch reserved and SDCA_CASCADE fields */
1404 		ret = sdw_write_no_pm(slave, SDW_DP0_INT, clear);
1405 		if (ret < 0) {
1406 			dev_err(&slave->dev,
1407 				"SDW_DP0_INT write failed:%d\n", ret);
1408 			return ret;
1409 		}
1410 
1411 		/* Read DP0 interrupt again */
1412 		status2 = sdw_read_no_pm(slave, SDW_DP0_INT);
1413 		if (status2 < 0) {
1414 			dev_err(&slave->dev,
1415 				"SDW_DP0_INT read failed:%d\n", status2);
1416 			return status2;
1417 		}
1418 		/* filter to limit loop to interrupts identified in the first status read */
1419 		status &= status2;
1420 
1421 		count++;
1422 
1423 		/* we can get alerts while processing so keep retrying */
1424 	} while ((status & SDW_DP0_INTERRUPTS) && (count < SDW_READ_INTR_CLEAR_RETRY));
1425 
1426 	if (count == SDW_READ_INTR_CLEAR_RETRY)
1427 		dev_warn(&slave->dev, "Reached MAX_RETRY on DP0 read\n");
1428 
1429 	return ret;
1430 }
1431 
1432 static int sdw_handle_port_interrupt(struct sdw_slave *slave,
1433 				     int port, u8 *slave_status)
1434 {
1435 	u8 clear, impl_int_mask;
1436 	int status, status2, ret, count = 0;
1437 	u32 addr;
1438 
1439 	if (port == 0)
1440 		return sdw_handle_dp0_interrupt(slave, slave_status);
1441 
1442 	addr = SDW_DPN_INT(port);
1443 	status = sdw_read_no_pm(slave, addr);
1444 	if (status < 0) {
1445 		dev_err(&slave->dev,
1446 			"SDW_DPN_INT read failed:%d\n", status);
1447 
1448 		return status;
1449 	}
1450 
1451 	do {
1452 		clear = status & ~SDW_DPN_INTERRUPTS;
1453 
1454 		if (status & SDW_DPN_INT_TEST_FAIL) {
1455 			dev_err(&slave->dev, "Test fail for port:%d\n", port);
1456 			clear |= SDW_DPN_INT_TEST_FAIL;
1457 		}
1458 
1459 		/*
1460 		 * Assumption: PORT_READY interrupt will be received only
1461 		 * for ports implementing CP_SM.
1462 		 */
1463 		if (status & SDW_DPN_INT_PORT_READY) {
1464 			complete(&slave->port_ready[port]);
1465 			clear |= SDW_DPN_INT_PORT_READY;
1466 		}
1467 
1468 		impl_int_mask = SDW_DPN_INT_IMPDEF1 |
1469 			SDW_DPN_INT_IMPDEF2 | SDW_DPN_INT_IMPDEF3;
1470 
1471 		if (status & impl_int_mask) {
1472 			clear |= impl_int_mask;
1473 			*slave_status = clear;
1474 		}
1475 
1476 		/* clear the interrupt but don't touch reserved fields */
1477 		ret = sdw_write_no_pm(slave, addr, clear);
1478 		if (ret < 0) {
1479 			dev_err(&slave->dev,
1480 				"SDW_DPN_INT write failed:%d\n", ret);
1481 			return ret;
1482 		}
1483 
1484 		/* Read DPN interrupt again */
1485 		status2 = sdw_read_no_pm(slave, addr);
1486 		if (status2 < 0) {
1487 			dev_err(&slave->dev,
1488 				"SDW_DPN_INT read failed:%d\n", status2);
1489 			return status2;
1490 		}
1491 		/* filter to limit loop to interrupts identified in the first status read */
1492 		status &= status2;
1493 
1494 		count++;
1495 
1496 		/* we can get alerts while processing so keep retrying */
1497 	} while ((status & SDW_DPN_INTERRUPTS) && (count < SDW_READ_INTR_CLEAR_RETRY));
1498 
1499 	if (count == SDW_READ_INTR_CLEAR_RETRY)
1500 		dev_warn(&slave->dev, "Reached MAX_RETRY on port read");
1501 
1502 	return ret;
1503 }
1504 
1505 static int sdw_handle_slave_alerts(struct sdw_slave *slave)
1506 {
1507 	struct sdw_slave_intr_status slave_intr;
1508 	u8 clear = 0, bit, port_status[15] = {0};
1509 	int port_num, stat, ret, count = 0;
1510 	unsigned long port;
1511 	bool slave_notify;
1512 	u8 sdca_cascade = 0;
1513 	u8 buf, buf2[2], _buf, _buf2[2];
1514 	bool parity_check;
1515 	bool parity_quirk;
1516 
1517 	sdw_modify_slave_status(slave, SDW_SLAVE_ALERT);
1518 
1519 	ret = pm_runtime_get_sync(&slave->dev);
1520 	if (ret < 0 && ret != -EACCES) {
1521 		dev_err(&slave->dev, "Failed to resume device: %d\n", ret);
1522 		pm_runtime_put_noidle(&slave->dev);
1523 		return ret;
1524 	}
1525 
1526 	/* Read Intstat 1, Intstat 2 and Intstat 3 registers */
1527 	ret = sdw_read_no_pm(slave, SDW_SCP_INT1);
1528 	if (ret < 0) {
1529 		dev_err(&slave->dev,
1530 			"SDW_SCP_INT1 read failed:%d\n", ret);
1531 		goto io_err;
1532 	}
1533 	buf = ret;
1534 
1535 	ret = sdw_nread_no_pm(slave, SDW_SCP_INTSTAT2, 2, buf2);
1536 	if (ret < 0) {
1537 		dev_err(&slave->dev,
1538 			"SDW_SCP_INT2/3 read failed:%d\n", ret);
1539 		goto io_err;
1540 	}
1541 
1542 	if (slave->prop.is_sdca) {
1543 		ret = sdw_read_no_pm(slave, SDW_DP0_INT);
1544 		if (ret < 0) {
1545 			dev_err(&slave->dev,
1546 				"SDW_DP0_INT read failed:%d\n", ret);
1547 			goto io_err;
1548 		}
1549 		sdca_cascade = ret & SDW_DP0_SDCA_CASCADE;
1550 	}
1551 
1552 	do {
1553 		slave_notify = false;
1554 
1555 		/*
1556 		 * Check parity, bus clash and Slave (impl defined)
1557 		 * interrupt
1558 		 */
1559 		if (buf & SDW_SCP_INT1_PARITY) {
1560 			parity_check = slave->prop.scp_int1_mask & SDW_SCP_INT1_PARITY;
1561 			parity_quirk = !slave->first_interrupt_done &&
1562 				(slave->prop.quirks & SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY);
1563 
1564 			if (parity_check && !parity_quirk)
1565 				dev_err(&slave->dev, "Parity error detected\n");
1566 			clear |= SDW_SCP_INT1_PARITY;
1567 		}
1568 
1569 		if (buf & SDW_SCP_INT1_BUS_CLASH) {
1570 			if (slave->prop.scp_int1_mask & SDW_SCP_INT1_BUS_CLASH)
1571 				dev_err(&slave->dev, "Bus clash detected\n");
1572 			clear |= SDW_SCP_INT1_BUS_CLASH;
1573 		}
1574 
1575 		/*
1576 		 * When bus clash or parity errors are detected, such errors
1577 		 * are unlikely to be recoverable errors.
1578 		 * TODO: In such scenario, reset bus. Make this configurable
1579 		 * via sysfs property with bus reset being the default.
1580 		 */
1581 
1582 		if (buf & SDW_SCP_INT1_IMPL_DEF) {
1583 			if (slave->prop.scp_int1_mask & SDW_SCP_INT1_IMPL_DEF) {
1584 				dev_dbg(&slave->dev, "Slave impl defined interrupt\n");
1585 				slave_notify = true;
1586 			}
1587 			clear |= SDW_SCP_INT1_IMPL_DEF;
1588 		}
1589 
1590 		/* the SDCA interrupts are cleared in the codec driver .interrupt_callback() */
1591 		if (sdca_cascade)
1592 			slave_notify = true;
1593 
1594 		/* Check port 0 - 3 interrupts */
1595 		port = buf & SDW_SCP_INT1_PORT0_3;
1596 
1597 		/* To get port number corresponding to bits, shift it */
1598 		port = FIELD_GET(SDW_SCP_INT1_PORT0_3, port);
1599 		for_each_set_bit(bit, &port, 8) {
1600 			sdw_handle_port_interrupt(slave, bit,
1601 						  &port_status[bit]);
1602 		}
1603 
1604 		/* Check if cascade 2 interrupt is present */
1605 		if (buf & SDW_SCP_INT1_SCP2_CASCADE) {
1606 			port = buf2[0] & SDW_SCP_INTSTAT2_PORT4_10;
1607 			for_each_set_bit(bit, &port, 8) {
1608 				/* scp2 ports start from 4 */
1609 				port_num = bit + 3;
1610 				sdw_handle_port_interrupt(slave,
1611 						port_num,
1612 						&port_status[port_num]);
1613 			}
1614 		}
1615 
1616 		/* now check last cascade */
1617 		if (buf2[0] & SDW_SCP_INTSTAT2_SCP3_CASCADE) {
1618 			port = buf2[1] & SDW_SCP_INTSTAT3_PORT11_14;
1619 			for_each_set_bit(bit, &port, 8) {
1620 				/* scp3 ports start from 11 */
1621 				port_num = bit + 10;
1622 				sdw_handle_port_interrupt(slave,
1623 						port_num,
1624 						&port_status[port_num]);
1625 			}
1626 		}
1627 
1628 		/* Update the Slave driver */
1629 		if (slave_notify && slave->ops &&
1630 		    slave->ops->interrupt_callback) {
1631 			slave_intr.sdca_cascade = sdca_cascade;
1632 			slave_intr.control_port = clear;
1633 			memcpy(slave_intr.port, &port_status,
1634 			       sizeof(slave_intr.port));
1635 
1636 			slave->ops->interrupt_callback(slave, &slave_intr);
1637 		}
1638 
1639 		/* Ack interrupt */
1640 		ret = sdw_write_no_pm(slave, SDW_SCP_INT1, clear);
1641 		if (ret < 0) {
1642 			dev_err(&slave->dev,
1643 				"SDW_SCP_INT1 write failed:%d\n", ret);
1644 			goto io_err;
1645 		}
1646 
1647 		/* at this point all initial interrupt sources were handled */
1648 		slave->first_interrupt_done = true;
1649 
1650 		/*
1651 		 * Read status again to ensure no new interrupts arrived
1652 		 * while servicing interrupts.
1653 		 */
1654 		ret = sdw_read_no_pm(slave, SDW_SCP_INT1);
1655 		if (ret < 0) {
1656 			dev_err(&slave->dev,
1657 				"SDW_SCP_INT1 recheck read failed:%d\n", ret);
1658 			goto io_err;
1659 		}
1660 		_buf = ret;
1661 
1662 		ret = sdw_nread_no_pm(slave, SDW_SCP_INTSTAT2, 2, _buf2);
1663 		if (ret < 0) {
1664 			dev_err(&slave->dev,
1665 				"SDW_SCP_INT2/3 recheck read failed:%d\n", ret);
1666 			goto io_err;
1667 		}
1668 
1669 		if (slave->prop.is_sdca) {
1670 			ret = sdw_read_no_pm(slave, SDW_DP0_INT);
1671 			if (ret < 0) {
1672 				dev_err(&slave->dev,
1673 					"SDW_DP0_INT recheck read failed:%d\n", ret);
1674 				goto io_err;
1675 			}
1676 			sdca_cascade = ret & SDW_DP0_SDCA_CASCADE;
1677 		}
1678 
1679 		/*
1680 		 * Make sure no interrupts are pending, but filter to limit loop
1681 		 * to interrupts identified in the first status read
1682 		 */
1683 		buf &= _buf;
1684 		buf2[0] &= _buf2[0];
1685 		buf2[1] &= _buf2[1];
1686 		stat = buf || buf2[0] || buf2[1] || sdca_cascade;
1687 
1688 		/*
1689 		 * Exit loop if Slave is continuously in ALERT state even
1690 		 * after servicing the interrupt multiple times.
1691 		 */
1692 		count++;
1693 
1694 		/* we can get alerts while processing so keep retrying */
1695 	} while (stat != 0 && count < SDW_READ_INTR_CLEAR_RETRY);
1696 
1697 	if (count == SDW_READ_INTR_CLEAR_RETRY)
1698 		dev_warn(&slave->dev, "Reached MAX_RETRY on alert read\n");
1699 
1700 io_err:
1701 	pm_runtime_mark_last_busy(&slave->dev);
1702 	pm_runtime_put_autosuspend(&slave->dev);
1703 
1704 	return ret;
1705 }
1706 
1707 static int sdw_update_slave_status(struct sdw_slave *slave,
1708 				   enum sdw_slave_status status)
1709 {
1710 	unsigned long time;
1711 
1712 	if (!slave->probed) {
1713 		/*
1714 		 * the slave status update is typically handled in an
1715 		 * interrupt thread, which can race with the driver
1716 		 * probe, e.g. when a module needs to be loaded.
1717 		 *
1718 		 * make sure the probe is complete before updating
1719 		 * status.
1720 		 */
1721 		time = wait_for_completion_timeout(&slave->probe_complete,
1722 				msecs_to_jiffies(DEFAULT_PROBE_TIMEOUT));
1723 		if (!time) {
1724 			dev_err(&slave->dev, "Probe not complete, timed out\n");
1725 			return -ETIMEDOUT;
1726 		}
1727 	}
1728 
1729 	if (!slave->ops || !slave->ops->update_status)
1730 		return 0;
1731 
1732 	return slave->ops->update_status(slave, status);
1733 }
1734 
1735 /**
1736  * sdw_handle_slave_status() - Handle Slave status
1737  * @bus: SDW bus instance
1738  * @status: Status for all Slave(s)
1739  */
1740 int sdw_handle_slave_status(struct sdw_bus *bus,
1741 			    enum sdw_slave_status status[])
1742 {
1743 	enum sdw_slave_status prev_status;
1744 	struct sdw_slave *slave;
1745 	bool attached_initializing;
1746 	int i, ret = 0;
1747 
1748 	/* first check if any Slaves fell off the bus */
1749 	for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1750 		mutex_lock(&bus->bus_lock);
1751 		if (test_bit(i, bus->assigned) == false) {
1752 			mutex_unlock(&bus->bus_lock);
1753 			continue;
1754 		}
1755 		mutex_unlock(&bus->bus_lock);
1756 
1757 		slave = sdw_get_slave(bus, i);
1758 		if (!slave)
1759 			continue;
1760 
1761 		if (status[i] == SDW_SLAVE_UNATTACHED &&
1762 		    slave->status != SDW_SLAVE_UNATTACHED)
1763 			sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
1764 	}
1765 
1766 	if (status[0] == SDW_SLAVE_ATTACHED) {
1767 		dev_dbg(bus->dev, "Slave attached, programming device number\n");
1768 		ret = sdw_program_device_num(bus);
1769 		if (ret < 0)
1770 			dev_err(bus->dev, "Slave attach failed: %d\n", ret);
1771 		/*
1772 		 * programming a device number will have side effects,
1773 		 * so we deal with other devices at a later time
1774 		 */
1775 		return ret;
1776 	}
1777 
1778 	/* Continue to check other slave statuses */
1779 	for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1780 		mutex_lock(&bus->bus_lock);
1781 		if (test_bit(i, bus->assigned) == false) {
1782 			mutex_unlock(&bus->bus_lock);
1783 			continue;
1784 		}
1785 		mutex_unlock(&bus->bus_lock);
1786 
1787 		slave = sdw_get_slave(bus, i);
1788 		if (!slave)
1789 			continue;
1790 
1791 		attached_initializing = false;
1792 
1793 		switch (status[i]) {
1794 		case SDW_SLAVE_UNATTACHED:
1795 			if (slave->status == SDW_SLAVE_UNATTACHED)
1796 				break;
1797 
1798 			sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
1799 			break;
1800 
1801 		case SDW_SLAVE_ALERT:
1802 			ret = sdw_handle_slave_alerts(slave);
1803 			if (ret < 0)
1804 				dev_err(&slave->dev,
1805 					"Slave %d alert handling failed: %d\n",
1806 					i, ret);
1807 			break;
1808 
1809 		case SDW_SLAVE_ATTACHED:
1810 			if (slave->status == SDW_SLAVE_ATTACHED)
1811 				break;
1812 
1813 			prev_status = slave->status;
1814 			sdw_modify_slave_status(slave, SDW_SLAVE_ATTACHED);
1815 
1816 			if (prev_status == SDW_SLAVE_ALERT)
1817 				break;
1818 
1819 			attached_initializing = true;
1820 
1821 			ret = sdw_initialize_slave(slave);
1822 			if (ret < 0)
1823 				dev_err(&slave->dev,
1824 					"Slave %d initialization failed: %d\n",
1825 					i, ret);
1826 
1827 			break;
1828 
1829 		default:
1830 			dev_err(&slave->dev, "Invalid slave %d status:%d\n",
1831 				i, status[i]);
1832 			break;
1833 		}
1834 
1835 		ret = sdw_update_slave_status(slave, status[i]);
1836 		if (ret < 0)
1837 			dev_err(&slave->dev,
1838 				"Update Slave status failed:%d\n", ret);
1839 		if (attached_initializing) {
1840 			dev_dbg(&slave->dev,
1841 				"%s: signaling initialization completion for Slave %d\n",
1842 				__func__, slave->dev_num);
1843 
1844 			complete(&slave->initialization_complete);
1845 		}
1846 	}
1847 
1848 	return ret;
1849 }
1850 EXPORT_SYMBOL(sdw_handle_slave_status);
1851 
1852 void sdw_clear_slave_status(struct sdw_bus *bus, u32 request)
1853 {
1854 	struct sdw_slave *slave;
1855 	int i;
1856 
1857 	/* Check all non-zero devices */
1858 	for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1859 		mutex_lock(&bus->bus_lock);
1860 		if (test_bit(i, bus->assigned) == false) {
1861 			mutex_unlock(&bus->bus_lock);
1862 			continue;
1863 		}
1864 		mutex_unlock(&bus->bus_lock);
1865 
1866 		slave = sdw_get_slave(bus, i);
1867 		if (!slave)
1868 			continue;
1869 
1870 		if (slave->status != SDW_SLAVE_UNATTACHED) {
1871 			sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
1872 			slave->first_interrupt_done = false;
1873 		}
1874 
1875 		/* keep track of request, used in pm_runtime resume */
1876 		slave->unattach_request = request;
1877 	}
1878 }
1879 EXPORT_SYMBOL(sdw_clear_slave_status);
1880