xref: /linux/drivers/thunderbolt/switch.c (revision 26fbb4c8c7c3ee9a4c3b4de555a8587b5a19154e)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Thunderbolt driver - switch/port utility functions
4  *
5  * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
6  * Copyright (C) 2018, Intel Corporation
7  */
8 
9 #include <linux/delay.h>
10 #include <linux/idr.h>
11 #include <linux/nvmem-provider.h>
12 #include <linux/pm_runtime.h>
13 #include <linux/sched/signal.h>
14 #include <linux/sizes.h>
15 #include <linux/slab.h>
16 
17 #include "tb.h"
18 
19 /* Switch NVM support */
20 
21 #define NVM_CSS			0x10
22 
23 struct nvm_auth_status {
24 	struct list_head list;
25 	uuid_t uuid;
26 	u32 status;
27 };
28 
29 enum nvm_write_ops {
30 	WRITE_AND_AUTHENTICATE = 1,
31 	WRITE_ONLY = 2,
32 };
33 
34 /*
35  * Hold NVM authentication failure status per switch This information
36  * needs to stay around even when the switch gets power cycled so we
37  * keep it separately.
38  */
39 static LIST_HEAD(nvm_auth_status_cache);
40 static DEFINE_MUTEX(nvm_auth_status_lock);
41 
42 static struct nvm_auth_status *__nvm_get_auth_status(const struct tb_switch *sw)
43 {
44 	struct nvm_auth_status *st;
45 
46 	list_for_each_entry(st, &nvm_auth_status_cache, list) {
47 		if (uuid_equal(&st->uuid, sw->uuid))
48 			return st;
49 	}
50 
51 	return NULL;
52 }
53 
54 static void nvm_get_auth_status(const struct tb_switch *sw, u32 *status)
55 {
56 	struct nvm_auth_status *st;
57 
58 	mutex_lock(&nvm_auth_status_lock);
59 	st = __nvm_get_auth_status(sw);
60 	mutex_unlock(&nvm_auth_status_lock);
61 
62 	*status = st ? st->status : 0;
63 }
64 
65 static void nvm_set_auth_status(const struct tb_switch *sw, u32 status)
66 {
67 	struct nvm_auth_status *st;
68 
69 	if (WARN_ON(!sw->uuid))
70 		return;
71 
72 	mutex_lock(&nvm_auth_status_lock);
73 	st = __nvm_get_auth_status(sw);
74 
75 	if (!st) {
76 		st = kzalloc(sizeof(*st), GFP_KERNEL);
77 		if (!st)
78 			goto unlock;
79 
80 		memcpy(&st->uuid, sw->uuid, sizeof(st->uuid));
81 		INIT_LIST_HEAD(&st->list);
82 		list_add_tail(&st->list, &nvm_auth_status_cache);
83 	}
84 
85 	st->status = status;
86 unlock:
87 	mutex_unlock(&nvm_auth_status_lock);
88 }
89 
90 static void nvm_clear_auth_status(const struct tb_switch *sw)
91 {
92 	struct nvm_auth_status *st;
93 
94 	mutex_lock(&nvm_auth_status_lock);
95 	st = __nvm_get_auth_status(sw);
96 	if (st) {
97 		list_del(&st->list);
98 		kfree(st);
99 	}
100 	mutex_unlock(&nvm_auth_status_lock);
101 }
102 
103 static int nvm_validate_and_write(struct tb_switch *sw)
104 {
105 	unsigned int image_size, hdr_size;
106 	const u8 *buf = sw->nvm->buf;
107 	u16 ds_size;
108 	int ret;
109 
110 	if (!buf)
111 		return -EINVAL;
112 
113 	image_size = sw->nvm->buf_data_size;
114 	if (image_size < NVM_MIN_SIZE || image_size > NVM_MAX_SIZE)
115 		return -EINVAL;
116 
117 	/*
118 	 * FARB pointer must point inside the image and must at least
119 	 * contain parts of the digital section we will be reading here.
120 	 */
121 	hdr_size = (*(u32 *)buf) & 0xffffff;
122 	if (hdr_size + NVM_DEVID + 2 >= image_size)
123 		return -EINVAL;
124 
125 	/* Digital section start should be aligned to 4k page */
126 	if (!IS_ALIGNED(hdr_size, SZ_4K))
127 		return -EINVAL;
128 
129 	/*
130 	 * Read digital section size and check that it also fits inside
131 	 * the image.
132 	 */
133 	ds_size = *(u16 *)(buf + hdr_size);
134 	if (ds_size >= image_size)
135 		return -EINVAL;
136 
137 	if (!sw->safe_mode) {
138 		u16 device_id;
139 
140 		/*
141 		 * Make sure the device ID in the image matches the one
142 		 * we read from the switch config space.
143 		 */
144 		device_id = *(u16 *)(buf + hdr_size + NVM_DEVID);
145 		if (device_id != sw->config.device_id)
146 			return -EINVAL;
147 
148 		if (sw->generation < 3) {
149 			/* Write CSS headers first */
150 			ret = dma_port_flash_write(sw->dma_port,
151 				DMA_PORT_CSS_ADDRESS, buf + NVM_CSS,
152 				DMA_PORT_CSS_MAX_SIZE);
153 			if (ret)
154 				return ret;
155 		}
156 
157 		/* Skip headers in the image */
158 		buf += hdr_size;
159 		image_size -= hdr_size;
160 	}
161 
162 	if (tb_switch_is_usb4(sw))
163 		ret = usb4_switch_nvm_write(sw, 0, buf, image_size);
164 	else
165 		ret = dma_port_flash_write(sw->dma_port, 0, buf, image_size);
166 	if (!ret)
167 		sw->nvm->flushed = true;
168 	return ret;
169 }
170 
171 static int nvm_authenticate_host_dma_port(struct tb_switch *sw)
172 {
173 	int ret = 0;
174 
175 	/*
176 	 * Root switch NVM upgrade requires that we disconnect the
177 	 * existing paths first (in case it is not in safe mode
178 	 * already).
179 	 */
180 	if (!sw->safe_mode) {
181 		u32 status;
182 
183 		ret = tb_domain_disconnect_all_paths(sw->tb);
184 		if (ret)
185 			return ret;
186 		/*
187 		 * The host controller goes away pretty soon after this if
188 		 * everything goes well so getting timeout is expected.
189 		 */
190 		ret = dma_port_flash_update_auth(sw->dma_port);
191 		if (!ret || ret == -ETIMEDOUT)
192 			return 0;
193 
194 		/*
195 		 * Any error from update auth operation requires power
196 		 * cycling of the host router.
197 		 */
198 		tb_sw_warn(sw, "failed to authenticate NVM, power cycling\n");
199 		if (dma_port_flash_update_auth_status(sw->dma_port, &status) > 0)
200 			nvm_set_auth_status(sw, status);
201 	}
202 
203 	/*
204 	 * From safe mode we can get out by just power cycling the
205 	 * switch.
206 	 */
207 	dma_port_power_cycle(sw->dma_port);
208 	return ret;
209 }
210 
211 static int nvm_authenticate_device_dma_port(struct tb_switch *sw)
212 {
213 	int ret, retries = 10;
214 
215 	ret = dma_port_flash_update_auth(sw->dma_port);
216 	switch (ret) {
217 	case 0:
218 	case -ETIMEDOUT:
219 	case -EACCES:
220 	case -EINVAL:
221 		/* Power cycle is required */
222 		break;
223 	default:
224 		return ret;
225 	}
226 
227 	/*
228 	 * Poll here for the authentication status. It takes some time
229 	 * for the device to respond (we get timeout for a while). Once
230 	 * we get response the device needs to be power cycled in order
231 	 * to the new NVM to be taken into use.
232 	 */
233 	do {
234 		u32 status;
235 
236 		ret = dma_port_flash_update_auth_status(sw->dma_port, &status);
237 		if (ret < 0 && ret != -ETIMEDOUT)
238 			return ret;
239 		if (ret > 0) {
240 			if (status) {
241 				tb_sw_warn(sw, "failed to authenticate NVM\n");
242 				nvm_set_auth_status(sw, status);
243 			}
244 
245 			tb_sw_info(sw, "power cycling the switch now\n");
246 			dma_port_power_cycle(sw->dma_port);
247 			return 0;
248 		}
249 
250 		msleep(500);
251 	} while (--retries);
252 
253 	return -ETIMEDOUT;
254 }
255 
256 static void nvm_authenticate_start_dma_port(struct tb_switch *sw)
257 {
258 	struct pci_dev *root_port;
259 
260 	/*
261 	 * During host router NVM upgrade we should not allow root port to
262 	 * go into D3cold because some root ports cannot trigger PME
263 	 * itself. To be on the safe side keep the root port in D0 during
264 	 * the whole upgrade process.
265 	 */
266 	root_port = pcie_find_root_port(sw->tb->nhi->pdev);
267 	if (root_port)
268 		pm_runtime_get_noresume(&root_port->dev);
269 }
270 
271 static void nvm_authenticate_complete_dma_port(struct tb_switch *sw)
272 {
273 	struct pci_dev *root_port;
274 
275 	root_port = pcie_find_root_port(sw->tb->nhi->pdev);
276 	if (root_port)
277 		pm_runtime_put(&root_port->dev);
278 }
279 
280 static inline bool nvm_readable(struct tb_switch *sw)
281 {
282 	if (tb_switch_is_usb4(sw)) {
283 		/*
284 		 * USB4 devices must support NVM operations but it is
285 		 * optional for hosts. Therefore we query the NVM sector
286 		 * size here and if it is supported assume NVM
287 		 * operations are implemented.
288 		 */
289 		return usb4_switch_nvm_sector_size(sw) > 0;
290 	}
291 
292 	/* Thunderbolt 2 and 3 devices support NVM through DMA port */
293 	return !!sw->dma_port;
294 }
295 
296 static inline bool nvm_upgradeable(struct tb_switch *sw)
297 {
298 	if (sw->no_nvm_upgrade)
299 		return false;
300 	return nvm_readable(sw);
301 }
302 
303 static inline int nvm_read(struct tb_switch *sw, unsigned int address,
304 			   void *buf, size_t size)
305 {
306 	if (tb_switch_is_usb4(sw))
307 		return usb4_switch_nvm_read(sw, address, buf, size);
308 	return dma_port_flash_read(sw->dma_port, address, buf, size);
309 }
310 
311 static int nvm_authenticate(struct tb_switch *sw)
312 {
313 	int ret;
314 
315 	if (tb_switch_is_usb4(sw))
316 		return usb4_switch_nvm_authenticate(sw);
317 
318 	if (!tb_route(sw)) {
319 		nvm_authenticate_start_dma_port(sw);
320 		ret = nvm_authenticate_host_dma_port(sw);
321 	} else {
322 		ret = nvm_authenticate_device_dma_port(sw);
323 	}
324 
325 	return ret;
326 }
327 
328 static int tb_switch_nvm_read(void *priv, unsigned int offset, void *val,
329 			      size_t bytes)
330 {
331 	struct tb_nvm *nvm = priv;
332 	struct tb_switch *sw = tb_to_switch(nvm->dev);
333 	int ret;
334 
335 	pm_runtime_get_sync(&sw->dev);
336 
337 	if (!mutex_trylock(&sw->tb->lock)) {
338 		ret = restart_syscall();
339 		goto out;
340 	}
341 
342 	ret = nvm_read(sw, offset, val, bytes);
343 	mutex_unlock(&sw->tb->lock);
344 
345 out:
346 	pm_runtime_mark_last_busy(&sw->dev);
347 	pm_runtime_put_autosuspend(&sw->dev);
348 
349 	return ret;
350 }
351 
352 static int tb_switch_nvm_write(void *priv, unsigned int offset, void *val,
353 			       size_t bytes)
354 {
355 	struct tb_nvm *nvm = priv;
356 	struct tb_switch *sw = tb_to_switch(nvm->dev);
357 	int ret;
358 
359 	if (!mutex_trylock(&sw->tb->lock))
360 		return restart_syscall();
361 
362 	/*
363 	 * Since writing the NVM image might require some special steps,
364 	 * for example when CSS headers are written, we cache the image
365 	 * locally here and handle the special cases when the user asks
366 	 * us to authenticate the image.
367 	 */
368 	ret = tb_nvm_write_buf(nvm, offset, val, bytes);
369 	mutex_unlock(&sw->tb->lock);
370 
371 	return ret;
372 }
373 
374 static int tb_switch_nvm_add(struct tb_switch *sw)
375 {
376 	struct tb_nvm *nvm;
377 	u32 val;
378 	int ret;
379 
380 	if (!nvm_readable(sw))
381 		return 0;
382 
383 	/*
384 	 * The NVM format of non-Intel hardware is not known so
385 	 * currently restrict NVM upgrade for Intel hardware. We may
386 	 * relax this in the future when we learn other NVM formats.
387 	 */
388 	if (sw->config.vendor_id != PCI_VENDOR_ID_INTEL &&
389 	    sw->config.vendor_id != 0x8087) {
390 		dev_info(&sw->dev,
391 			 "NVM format of vendor %#x is not known, disabling NVM upgrade\n",
392 			 sw->config.vendor_id);
393 		return 0;
394 	}
395 
396 	nvm = tb_nvm_alloc(&sw->dev);
397 	if (IS_ERR(nvm))
398 		return PTR_ERR(nvm);
399 
400 	/*
401 	 * If the switch is in safe-mode the only accessible portion of
402 	 * the NVM is the non-active one where userspace is expected to
403 	 * write new functional NVM.
404 	 */
405 	if (!sw->safe_mode) {
406 		u32 nvm_size, hdr_size;
407 
408 		ret = nvm_read(sw, NVM_FLASH_SIZE, &val, sizeof(val));
409 		if (ret)
410 			goto err_nvm;
411 
412 		hdr_size = sw->generation < 3 ? SZ_8K : SZ_16K;
413 		nvm_size = (SZ_1M << (val & 7)) / 8;
414 		nvm_size = (nvm_size - hdr_size) / 2;
415 
416 		ret = nvm_read(sw, NVM_VERSION, &val, sizeof(val));
417 		if (ret)
418 			goto err_nvm;
419 
420 		nvm->major = val >> 16;
421 		nvm->minor = val >> 8;
422 
423 		ret = tb_nvm_add_active(nvm, nvm_size, tb_switch_nvm_read);
424 		if (ret)
425 			goto err_nvm;
426 	}
427 
428 	if (!sw->no_nvm_upgrade) {
429 		ret = tb_nvm_add_non_active(nvm, NVM_MAX_SIZE,
430 					    tb_switch_nvm_write);
431 		if (ret)
432 			goto err_nvm;
433 	}
434 
435 	sw->nvm = nvm;
436 	return 0;
437 
438 err_nvm:
439 	tb_nvm_free(nvm);
440 	return ret;
441 }
442 
443 static void tb_switch_nvm_remove(struct tb_switch *sw)
444 {
445 	struct tb_nvm *nvm;
446 
447 	nvm = sw->nvm;
448 	sw->nvm = NULL;
449 
450 	if (!nvm)
451 		return;
452 
453 	/* Remove authentication status in case the switch is unplugged */
454 	if (!nvm->authenticating)
455 		nvm_clear_auth_status(sw);
456 
457 	tb_nvm_free(nvm);
458 }
459 
460 /* port utility functions */
461 
462 static const char *tb_port_type(struct tb_regs_port_header *port)
463 {
464 	switch (port->type >> 16) {
465 	case 0:
466 		switch ((u8) port->type) {
467 		case 0:
468 			return "Inactive";
469 		case 1:
470 			return "Port";
471 		case 2:
472 			return "NHI";
473 		default:
474 			return "unknown";
475 		}
476 	case 0x2:
477 		return "Ethernet";
478 	case 0x8:
479 		return "SATA";
480 	case 0xe:
481 		return "DP/HDMI";
482 	case 0x10:
483 		return "PCIe";
484 	case 0x20:
485 		return "USB";
486 	default:
487 		return "unknown";
488 	}
489 }
490 
491 static void tb_dump_port(struct tb *tb, struct tb_regs_port_header *port)
492 {
493 	tb_dbg(tb,
494 	       " Port %d: %x:%x (Revision: %d, TB Version: %d, Type: %s (%#x))\n",
495 	       port->port_number, port->vendor_id, port->device_id,
496 	       port->revision, port->thunderbolt_version, tb_port_type(port),
497 	       port->type);
498 	tb_dbg(tb, "  Max hop id (in/out): %d/%d\n",
499 	       port->max_in_hop_id, port->max_out_hop_id);
500 	tb_dbg(tb, "  Max counters: %d\n", port->max_counters);
501 	tb_dbg(tb, "  NFC Credits: %#x\n", port->nfc_credits);
502 }
503 
504 /**
505  * tb_port_state() - get connectedness state of a port
506  * @port: the port to check
507  *
508  * The port must have a TB_CAP_PHY (i.e. it should be a real port).
509  *
510  * Return: Returns an enum tb_port_state on success or an error code on failure.
511  */
512 int tb_port_state(struct tb_port *port)
513 {
514 	struct tb_cap_phy phy;
515 	int res;
516 	if (port->cap_phy == 0) {
517 		tb_port_WARN(port, "does not have a PHY\n");
518 		return -EINVAL;
519 	}
520 	res = tb_port_read(port, &phy, TB_CFG_PORT, port->cap_phy, 2);
521 	if (res)
522 		return res;
523 	return phy.state;
524 }
525 
526 /**
527  * tb_wait_for_port() - wait for a port to become ready
528  *
529  * Wait up to 1 second for a port to reach state TB_PORT_UP. If
530  * wait_if_unplugged is set then we also wait if the port is in state
531  * TB_PORT_UNPLUGGED (it takes a while for the device to be registered after
532  * switch resume). Otherwise we only wait if a device is registered but the link
533  * has not yet been established.
534  *
535  * Return: Returns an error code on failure. Returns 0 if the port is not
536  * connected or failed to reach state TB_PORT_UP within one second. Returns 1
537  * if the port is connected and in state TB_PORT_UP.
538  */
539 int tb_wait_for_port(struct tb_port *port, bool wait_if_unplugged)
540 {
541 	int retries = 10;
542 	int state;
543 	if (!port->cap_phy) {
544 		tb_port_WARN(port, "does not have PHY\n");
545 		return -EINVAL;
546 	}
547 	if (tb_is_upstream_port(port)) {
548 		tb_port_WARN(port, "is the upstream port\n");
549 		return -EINVAL;
550 	}
551 
552 	while (retries--) {
553 		state = tb_port_state(port);
554 		if (state < 0)
555 			return state;
556 		if (state == TB_PORT_DISABLED) {
557 			tb_port_dbg(port, "is disabled (state: 0)\n");
558 			return 0;
559 		}
560 		if (state == TB_PORT_UNPLUGGED) {
561 			if (wait_if_unplugged) {
562 				/* used during resume */
563 				tb_port_dbg(port,
564 					    "is unplugged (state: 7), retrying...\n");
565 				msleep(100);
566 				continue;
567 			}
568 			tb_port_dbg(port, "is unplugged (state: 7)\n");
569 			return 0;
570 		}
571 		if (state == TB_PORT_UP) {
572 			tb_port_dbg(port, "is connected, link is up (state: 2)\n");
573 			return 1;
574 		}
575 
576 		/*
577 		 * After plug-in the state is TB_PORT_CONNECTING. Give it some
578 		 * time.
579 		 */
580 		tb_port_dbg(port,
581 			    "is connected, link is not up (state: %d), retrying...\n",
582 			    state);
583 		msleep(100);
584 	}
585 	tb_port_warn(port,
586 		     "failed to reach state TB_PORT_UP. Ignoring port...\n");
587 	return 0;
588 }
589 
590 /**
591  * tb_port_add_nfc_credits() - add/remove non flow controlled credits to port
592  *
593  * Change the number of NFC credits allocated to @port by @credits. To remove
594  * NFC credits pass a negative amount of credits.
595  *
596  * Return: Returns 0 on success or an error code on failure.
597  */
598 int tb_port_add_nfc_credits(struct tb_port *port, int credits)
599 {
600 	u32 nfc_credits;
601 
602 	if (credits == 0 || port->sw->is_unplugged)
603 		return 0;
604 
605 	/*
606 	 * USB4 restricts programming NFC buffers to lane adapters only
607 	 * so skip other ports.
608 	 */
609 	if (tb_switch_is_usb4(port->sw) && !tb_port_is_null(port))
610 		return 0;
611 
612 	nfc_credits = port->config.nfc_credits & ADP_CS_4_NFC_BUFFERS_MASK;
613 	nfc_credits += credits;
614 
615 	tb_port_dbg(port, "adding %d NFC credits to %lu", credits,
616 		    port->config.nfc_credits & ADP_CS_4_NFC_BUFFERS_MASK);
617 
618 	port->config.nfc_credits &= ~ADP_CS_4_NFC_BUFFERS_MASK;
619 	port->config.nfc_credits |= nfc_credits;
620 
621 	return tb_port_write(port, &port->config.nfc_credits,
622 			     TB_CFG_PORT, ADP_CS_4, 1);
623 }
624 
625 /**
626  * tb_port_set_initial_credits() - Set initial port link credits allocated
627  * @port: Port to set the initial credits
628  * @credits: Number of credits to to allocate
629  *
630  * Set initial credits value to be used for ingress shared buffering.
631  */
632 int tb_port_set_initial_credits(struct tb_port *port, u32 credits)
633 {
634 	u32 data;
635 	int ret;
636 
637 	ret = tb_port_read(port, &data, TB_CFG_PORT, ADP_CS_5, 1);
638 	if (ret)
639 		return ret;
640 
641 	data &= ~ADP_CS_5_LCA_MASK;
642 	data |= (credits << ADP_CS_5_LCA_SHIFT) & ADP_CS_5_LCA_MASK;
643 
644 	return tb_port_write(port, &data, TB_CFG_PORT, ADP_CS_5, 1);
645 }
646 
647 /**
648  * tb_port_clear_counter() - clear a counter in TB_CFG_COUNTER
649  *
650  * Return: Returns 0 on success or an error code on failure.
651  */
652 int tb_port_clear_counter(struct tb_port *port, int counter)
653 {
654 	u32 zero[3] = { 0, 0, 0 };
655 	tb_port_dbg(port, "clearing counter %d\n", counter);
656 	return tb_port_write(port, zero, TB_CFG_COUNTERS, 3 * counter, 3);
657 }
658 
659 /**
660  * tb_port_unlock() - Unlock downstream port
661  * @port: Port to unlock
662  *
663  * Needed for USB4 but can be called for any CIO/USB4 ports. Makes the
664  * downstream router accessible for CM.
665  */
666 int tb_port_unlock(struct tb_port *port)
667 {
668 	if (tb_switch_is_icm(port->sw))
669 		return 0;
670 	if (!tb_port_is_null(port))
671 		return -EINVAL;
672 	if (tb_switch_is_usb4(port->sw))
673 		return usb4_port_unlock(port);
674 	return 0;
675 }
676 
677 static int __tb_port_enable(struct tb_port *port, bool enable)
678 {
679 	int ret;
680 	u32 phy;
681 
682 	if (!tb_port_is_null(port))
683 		return -EINVAL;
684 
685 	ret = tb_port_read(port, &phy, TB_CFG_PORT,
686 			   port->cap_phy + LANE_ADP_CS_1, 1);
687 	if (ret)
688 		return ret;
689 
690 	if (enable)
691 		phy &= ~LANE_ADP_CS_1_LD;
692 	else
693 		phy |= LANE_ADP_CS_1_LD;
694 
695 	return tb_port_write(port, &phy, TB_CFG_PORT,
696 			     port->cap_phy + LANE_ADP_CS_1, 1);
697 }
698 
699 /**
700  * tb_port_enable() - Enable lane adapter
701  * @port: Port to enable (can be %NULL)
702  *
703  * This is used for lane 0 and 1 adapters to enable it.
704  */
705 int tb_port_enable(struct tb_port *port)
706 {
707 	return __tb_port_enable(port, true);
708 }
709 
710 /**
711  * tb_port_disable() - Disable lane adapter
712  * @port: Port to disable (can be %NULL)
713  *
714  * This is used for lane 0 and 1 adapters to disable it.
715  */
716 int tb_port_disable(struct tb_port *port)
717 {
718 	return __tb_port_enable(port, false);
719 }
720 
721 /**
722  * tb_init_port() - initialize a port
723  *
724  * This is a helper method for tb_switch_alloc. Does not check or initialize
725  * any downstream switches.
726  *
727  * Return: Returns 0 on success or an error code on failure.
728  */
729 static int tb_init_port(struct tb_port *port)
730 {
731 	int res;
732 	int cap;
733 
734 	res = tb_port_read(port, &port->config, TB_CFG_PORT, 0, 8);
735 	if (res) {
736 		if (res == -ENODEV) {
737 			tb_dbg(port->sw->tb, " Port %d: not implemented\n",
738 			       port->port);
739 			port->disabled = true;
740 			return 0;
741 		}
742 		return res;
743 	}
744 
745 	/* Port 0 is the switch itself and has no PHY. */
746 	if (port->config.type == TB_TYPE_PORT && port->port != 0) {
747 		cap = tb_port_find_cap(port, TB_PORT_CAP_PHY);
748 
749 		if (cap > 0)
750 			port->cap_phy = cap;
751 		else
752 			tb_port_WARN(port, "non switch port without a PHY\n");
753 
754 		cap = tb_port_find_cap(port, TB_PORT_CAP_USB4);
755 		if (cap > 0)
756 			port->cap_usb4 = cap;
757 	} else if (port->port != 0) {
758 		cap = tb_port_find_cap(port, TB_PORT_CAP_ADAP);
759 		if (cap > 0)
760 			port->cap_adap = cap;
761 	}
762 
763 	tb_dump_port(port->sw->tb, &port->config);
764 
765 	/* Control port does not need HopID allocation */
766 	if (port->port) {
767 		ida_init(&port->in_hopids);
768 		ida_init(&port->out_hopids);
769 	}
770 
771 	INIT_LIST_HEAD(&port->list);
772 	return 0;
773 
774 }
775 
776 static int tb_port_alloc_hopid(struct tb_port *port, bool in, int min_hopid,
777 			       int max_hopid)
778 {
779 	int port_max_hopid;
780 	struct ida *ida;
781 
782 	if (in) {
783 		port_max_hopid = port->config.max_in_hop_id;
784 		ida = &port->in_hopids;
785 	} else {
786 		port_max_hopid = port->config.max_out_hop_id;
787 		ida = &port->out_hopids;
788 	}
789 
790 	/*
791 	 * NHI can use HopIDs 1-max for other adapters HopIDs 0-7 are
792 	 * reserved.
793 	 */
794 	if (!tb_port_is_nhi(port) && min_hopid < TB_PATH_MIN_HOPID)
795 		min_hopid = TB_PATH_MIN_HOPID;
796 
797 	if (max_hopid < 0 || max_hopid > port_max_hopid)
798 		max_hopid = port_max_hopid;
799 
800 	return ida_simple_get(ida, min_hopid, max_hopid + 1, GFP_KERNEL);
801 }
802 
803 /**
804  * tb_port_alloc_in_hopid() - Allocate input HopID from port
805  * @port: Port to allocate HopID for
806  * @min_hopid: Minimum acceptable input HopID
807  * @max_hopid: Maximum acceptable input HopID
808  *
809  * Return: HopID between @min_hopid and @max_hopid or negative errno in
810  * case of error.
811  */
812 int tb_port_alloc_in_hopid(struct tb_port *port, int min_hopid, int max_hopid)
813 {
814 	return tb_port_alloc_hopid(port, true, min_hopid, max_hopid);
815 }
816 
817 /**
818  * tb_port_alloc_out_hopid() - Allocate output HopID from port
819  * @port: Port to allocate HopID for
820  * @min_hopid: Minimum acceptable output HopID
821  * @max_hopid: Maximum acceptable output HopID
822  *
823  * Return: HopID between @min_hopid and @max_hopid or negative errno in
824  * case of error.
825  */
826 int tb_port_alloc_out_hopid(struct tb_port *port, int min_hopid, int max_hopid)
827 {
828 	return tb_port_alloc_hopid(port, false, min_hopid, max_hopid);
829 }
830 
831 /**
832  * tb_port_release_in_hopid() - Release allocated input HopID from port
833  * @port: Port whose HopID to release
834  * @hopid: HopID to release
835  */
836 void tb_port_release_in_hopid(struct tb_port *port, int hopid)
837 {
838 	ida_simple_remove(&port->in_hopids, hopid);
839 }
840 
841 /**
842  * tb_port_release_out_hopid() - Release allocated output HopID from port
843  * @port: Port whose HopID to release
844  * @hopid: HopID to release
845  */
846 void tb_port_release_out_hopid(struct tb_port *port, int hopid)
847 {
848 	ida_simple_remove(&port->out_hopids, hopid);
849 }
850 
851 static inline bool tb_switch_is_reachable(const struct tb_switch *parent,
852 					  const struct tb_switch *sw)
853 {
854 	u64 mask = (1ULL << parent->config.depth * 8) - 1;
855 	return (tb_route(parent) & mask) == (tb_route(sw) & mask);
856 }
857 
858 /**
859  * tb_next_port_on_path() - Return next port for given port on a path
860  * @start: Start port of the walk
861  * @end: End port of the walk
862  * @prev: Previous port (%NULL if this is the first)
863  *
864  * This function can be used to walk from one port to another if they
865  * are connected through zero or more switches. If the @prev is dual
866  * link port, the function follows that link and returns another end on
867  * that same link.
868  *
869  * If the @end port has been reached, return %NULL.
870  *
871  * Domain tb->lock must be held when this function is called.
872  */
873 struct tb_port *tb_next_port_on_path(struct tb_port *start, struct tb_port *end,
874 				     struct tb_port *prev)
875 {
876 	struct tb_port *next;
877 
878 	if (!prev)
879 		return start;
880 
881 	if (prev->sw == end->sw) {
882 		if (prev == end)
883 			return NULL;
884 		return end;
885 	}
886 
887 	if (tb_switch_is_reachable(prev->sw, end->sw)) {
888 		next = tb_port_at(tb_route(end->sw), prev->sw);
889 		/* Walk down the topology if next == prev */
890 		if (prev->remote &&
891 		    (next == prev || next->dual_link_port == prev))
892 			next = prev->remote;
893 	} else {
894 		if (tb_is_upstream_port(prev)) {
895 			next = prev->remote;
896 		} else {
897 			next = tb_upstream_port(prev->sw);
898 			/*
899 			 * Keep the same link if prev and next are both
900 			 * dual link ports.
901 			 */
902 			if (next->dual_link_port &&
903 			    next->link_nr != prev->link_nr) {
904 				next = next->dual_link_port;
905 			}
906 		}
907 	}
908 
909 	return next != prev ? next : NULL;
910 }
911 
912 /**
913  * tb_port_get_link_speed() - Get current link speed
914  * @port: Port to check (USB4 or CIO)
915  *
916  * Returns link speed in Gb/s or negative errno in case of failure.
917  */
918 int tb_port_get_link_speed(struct tb_port *port)
919 {
920 	u32 val, speed;
921 	int ret;
922 
923 	if (!port->cap_phy)
924 		return -EINVAL;
925 
926 	ret = tb_port_read(port, &val, TB_CFG_PORT,
927 			   port->cap_phy + LANE_ADP_CS_1, 1);
928 	if (ret)
929 		return ret;
930 
931 	speed = (val & LANE_ADP_CS_1_CURRENT_SPEED_MASK) >>
932 		LANE_ADP_CS_1_CURRENT_SPEED_SHIFT;
933 	return speed == LANE_ADP_CS_1_CURRENT_SPEED_GEN3 ? 20 : 10;
934 }
935 
936 /**
937  * tb_port_get_link_width() - Get current link width
938  * @port: Port to check (USB4 or CIO)
939  *
940  * Returns link width. Return values can be 1 (Single-Lane), 2 (Dual-Lane)
941  * or negative errno in case of failure.
942  */
943 int tb_port_get_link_width(struct tb_port *port)
944 {
945 	u32 val;
946 	int ret;
947 
948 	if (!port->cap_phy)
949 		return -EINVAL;
950 
951 	ret = tb_port_read(port, &val, TB_CFG_PORT,
952 			   port->cap_phy + LANE_ADP_CS_1, 1);
953 	if (ret)
954 		return ret;
955 
956 	return (val & LANE_ADP_CS_1_CURRENT_WIDTH_MASK) >>
957 		LANE_ADP_CS_1_CURRENT_WIDTH_SHIFT;
958 }
959 
960 static bool tb_port_is_width_supported(struct tb_port *port, int width)
961 {
962 	u32 phy, widths;
963 	int ret;
964 
965 	if (!port->cap_phy)
966 		return false;
967 
968 	ret = tb_port_read(port, &phy, TB_CFG_PORT,
969 			   port->cap_phy + LANE_ADP_CS_0, 1);
970 	if (ret)
971 		return false;
972 
973 	widths = (phy & LANE_ADP_CS_0_SUPPORTED_WIDTH_MASK) >>
974 		LANE_ADP_CS_0_SUPPORTED_WIDTH_SHIFT;
975 
976 	return !!(widths & width);
977 }
978 
979 static int tb_port_set_link_width(struct tb_port *port, unsigned int width)
980 {
981 	u32 val;
982 	int ret;
983 
984 	if (!port->cap_phy)
985 		return -EINVAL;
986 
987 	ret = tb_port_read(port, &val, TB_CFG_PORT,
988 			   port->cap_phy + LANE_ADP_CS_1, 1);
989 	if (ret)
990 		return ret;
991 
992 	val &= ~LANE_ADP_CS_1_TARGET_WIDTH_MASK;
993 	switch (width) {
994 	case 1:
995 		val |= LANE_ADP_CS_1_TARGET_WIDTH_SINGLE <<
996 			LANE_ADP_CS_1_TARGET_WIDTH_SHIFT;
997 		break;
998 	case 2:
999 		val |= LANE_ADP_CS_1_TARGET_WIDTH_DUAL <<
1000 			LANE_ADP_CS_1_TARGET_WIDTH_SHIFT;
1001 		break;
1002 	default:
1003 		return -EINVAL;
1004 	}
1005 
1006 	val |= LANE_ADP_CS_1_LB;
1007 
1008 	return tb_port_write(port, &val, TB_CFG_PORT,
1009 			     port->cap_phy + LANE_ADP_CS_1, 1);
1010 }
1011 
1012 /**
1013  * tb_port_lane_bonding_enable() - Enable bonding on port
1014  * @port: port to enable
1015  *
1016  * Enable bonding by setting the link width of the port and the
1017  * other port in case of dual link port.
1018  *
1019  * Return: %0 in case of success and negative errno in case of error
1020  */
1021 int tb_port_lane_bonding_enable(struct tb_port *port)
1022 {
1023 	int ret;
1024 
1025 	/*
1026 	 * Enable lane bonding for both links if not already enabled by
1027 	 * for example the boot firmware.
1028 	 */
1029 	ret = tb_port_get_link_width(port);
1030 	if (ret == 1) {
1031 		ret = tb_port_set_link_width(port, 2);
1032 		if (ret)
1033 			return ret;
1034 	}
1035 
1036 	ret = tb_port_get_link_width(port->dual_link_port);
1037 	if (ret == 1) {
1038 		ret = tb_port_set_link_width(port->dual_link_port, 2);
1039 		if (ret) {
1040 			tb_port_set_link_width(port, 1);
1041 			return ret;
1042 		}
1043 	}
1044 
1045 	port->bonded = true;
1046 	port->dual_link_port->bonded = true;
1047 
1048 	return 0;
1049 }
1050 
1051 /**
1052  * tb_port_lane_bonding_disable() - Disable bonding on port
1053  * @port: port to disable
1054  *
1055  * Disable bonding by setting the link width of the port and the
1056  * other port in case of dual link port.
1057  *
1058  */
1059 void tb_port_lane_bonding_disable(struct tb_port *port)
1060 {
1061 	port->dual_link_port->bonded = false;
1062 	port->bonded = false;
1063 
1064 	tb_port_set_link_width(port->dual_link_port, 1);
1065 	tb_port_set_link_width(port, 1);
1066 }
1067 
1068 /**
1069  * tb_port_is_enabled() - Is the adapter port enabled
1070  * @port: Port to check
1071  */
1072 bool tb_port_is_enabled(struct tb_port *port)
1073 {
1074 	switch (port->config.type) {
1075 	case TB_TYPE_PCIE_UP:
1076 	case TB_TYPE_PCIE_DOWN:
1077 		return tb_pci_port_is_enabled(port);
1078 
1079 	case TB_TYPE_DP_HDMI_IN:
1080 	case TB_TYPE_DP_HDMI_OUT:
1081 		return tb_dp_port_is_enabled(port);
1082 
1083 	case TB_TYPE_USB3_UP:
1084 	case TB_TYPE_USB3_DOWN:
1085 		return tb_usb3_port_is_enabled(port);
1086 
1087 	default:
1088 		return false;
1089 	}
1090 }
1091 
1092 /**
1093  * tb_usb3_port_is_enabled() - Is the USB3 adapter port enabled
1094  * @port: USB3 adapter port to check
1095  */
1096 bool tb_usb3_port_is_enabled(struct tb_port *port)
1097 {
1098 	u32 data;
1099 
1100 	if (tb_port_read(port, &data, TB_CFG_PORT,
1101 			 port->cap_adap + ADP_USB3_CS_0, 1))
1102 		return false;
1103 
1104 	return !!(data & ADP_USB3_CS_0_PE);
1105 }
1106 
1107 /**
1108  * tb_usb3_port_enable() - Enable USB3 adapter port
1109  * @port: USB3 adapter port to enable
1110  * @enable: Enable/disable the USB3 adapter
1111  */
1112 int tb_usb3_port_enable(struct tb_port *port, bool enable)
1113 {
1114 	u32 word = enable ? (ADP_USB3_CS_0_PE | ADP_USB3_CS_0_V)
1115 			  : ADP_USB3_CS_0_V;
1116 
1117 	if (!port->cap_adap)
1118 		return -ENXIO;
1119 	return tb_port_write(port, &word, TB_CFG_PORT,
1120 			     port->cap_adap + ADP_USB3_CS_0, 1);
1121 }
1122 
1123 /**
1124  * tb_pci_port_is_enabled() - Is the PCIe adapter port enabled
1125  * @port: PCIe port to check
1126  */
1127 bool tb_pci_port_is_enabled(struct tb_port *port)
1128 {
1129 	u32 data;
1130 
1131 	if (tb_port_read(port, &data, TB_CFG_PORT,
1132 			 port->cap_adap + ADP_PCIE_CS_0, 1))
1133 		return false;
1134 
1135 	return !!(data & ADP_PCIE_CS_0_PE);
1136 }
1137 
1138 /**
1139  * tb_pci_port_enable() - Enable PCIe adapter port
1140  * @port: PCIe port to enable
1141  * @enable: Enable/disable the PCIe adapter
1142  */
1143 int tb_pci_port_enable(struct tb_port *port, bool enable)
1144 {
1145 	u32 word = enable ? ADP_PCIE_CS_0_PE : 0x0;
1146 	if (!port->cap_adap)
1147 		return -ENXIO;
1148 	return tb_port_write(port, &word, TB_CFG_PORT,
1149 			     port->cap_adap + ADP_PCIE_CS_0, 1);
1150 }
1151 
1152 /**
1153  * tb_dp_port_hpd_is_active() - Is HPD already active
1154  * @port: DP out port to check
1155  *
1156  * Checks if the DP OUT adapter port has HDP bit already set.
1157  */
1158 int tb_dp_port_hpd_is_active(struct tb_port *port)
1159 {
1160 	u32 data;
1161 	int ret;
1162 
1163 	ret = tb_port_read(port, &data, TB_CFG_PORT,
1164 			   port->cap_adap + ADP_DP_CS_2, 1);
1165 	if (ret)
1166 		return ret;
1167 
1168 	return !!(data & ADP_DP_CS_2_HDP);
1169 }
1170 
1171 /**
1172  * tb_dp_port_hpd_clear() - Clear HPD from DP IN port
1173  * @port: Port to clear HPD
1174  *
1175  * If the DP IN port has HDP set, this function can be used to clear it.
1176  */
1177 int tb_dp_port_hpd_clear(struct tb_port *port)
1178 {
1179 	u32 data;
1180 	int ret;
1181 
1182 	ret = tb_port_read(port, &data, TB_CFG_PORT,
1183 			   port->cap_adap + ADP_DP_CS_3, 1);
1184 	if (ret)
1185 		return ret;
1186 
1187 	data |= ADP_DP_CS_3_HDPC;
1188 	return tb_port_write(port, &data, TB_CFG_PORT,
1189 			     port->cap_adap + ADP_DP_CS_3, 1);
1190 }
1191 
1192 /**
1193  * tb_dp_port_set_hops() - Set video/aux Hop IDs for DP port
1194  * @port: DP IN/OUT port to set hops
1195  * @video: Video Hop ID
1196  * @aux_tx: AUX TX Hop ID
1197  * @aux_rx: AUX RX Hop ID
1198  *
1199  * Programs specified Hop IDs for DP IN/OUT port.
1200  */
1201 int tb_dp_port_set_hops(struct tb_port *port, unsigned int video,
1202 			unsigned int aux_tx, unsigned int aux_rx)
1203 {
1204 	u32 data[2];
1205 	int ret;
1206 
1207 	ret = tb_port_read(port, data, TB_CFG_PORT,
1208 			   port->cap_adap + ADP_DP_CS_0, ARRAY_SIZE(data));
1209 	if (ret)
1210 		return ret;
1211 
1212 	data[0] &= ~ADP_DP_CS_0_VIDEO_HOPID_MASK;
1213 	data[1] &= ~ADP_DP_CS_1_AUX_RX_HOPID_MASK;
1214 	data[1] &= ~ADP_DP_CS_1_AUX_RX_HOPID_MASK;
1215 
1216 	data[0] |= (video << ADP_DP_CS_0_VIDEO_HOPID_SHIFT) &
1217 		ADP_DP_CS_0_VIDEO_HOPID_MASK;
1218 	data[1] |= aux_tx & ADP_DP_CS_1_AUX_TX_HOPID_MASK;
1219 	data[1] |= (aux_rx << ADP_DP_CS_1_AUX_RX_HOPID_SHIFT) &
1220 		ADP_DP_CS_1_AUX_RX_HOPID_MASK;
1221 
1222 	return tb_port_write(port, data, TB_CFG_PORT,
1223 			     port->cap_adap + ADP_DP_CS_0, ARRAY_SIZE(data));
1224 }
1225 
1226 /**
1227  * tb_dp_port_is_enabled() - Is DP adapter port enabled
1228  * @port: DP adapter port to check
1229  */
1230 bool tb_dp_port_is_enabled(struct tb_port *port)
1231 {
1232 	u32 data[2];
1233 
1234 	if (tb_port_read(port, data, TB_CFG_PORT, port->cap_adap + ADP_DP_CS_0,
1235 			 ARRAY_SIZE(data)))
1236 		return false;
1237 
1238 	return !!(data[0] & (ADP_DP_CS_0_VE | ADP_DP_CS_0_AE));
1239 }
1240 
1241 /**
1242  * tb_dp_port_enable() - Enables/disables DP paths of a port
1243  * @port: DP IN/OUT port
1244  * @enable: Enable/disable DP path
1245  *
1246  * Once Hop IDs are programmed DP paths can be enabled or disabled by
1247  * calling this function.
1248  */
1249 int tb_dp_port_enable(struct tb_port *port, bool enable)
1250 {
1251 	u32 data[2];
1252 	int ret;
1253 
1254 	ret = tb_port_read(port, data, TB_CFG_PORT,
1255 			  port->cap_adap + ADP_DP_CS_0, ARRAY_SIZE(data));
1256 	if (ret)
1257 		return ret;
1258 
1259 	if (enable)
1260 		data[0] |= ADP_DP_CS_0_VE | ADP_DP_CS_0_AE;
1261 	else
1262 		data[0] &= ~(ADP_DP_CS_0_VE | ADP_DP_CS_0_AE);
1263 
1264 	return tb_port_write(port, data, TB_CFG_PORT,
1265 			     port->cap_adap + ADP_DP_CS_0, ARRAY_SIZE(data));
1266 }
1267 
1268 /* switch utility functions */
1269 
1270 static const char *tb_switch_generation_name(const struct tb_switch *sw)
1271 {
1272 	switch (sw->generation) {
1273 	case 1:
1274 		return "Thunderbolt 1";
1275 	case 2:
1276 		return "Thunderbolt 2";
1277 	case 3:
1278 		return "Thunderbolt 3";
1279 	case 4:
1280 		return "USB4";
1281 	default:
1282 		return "Unknown";
1283 	}
1284 }
1285 
1286 static void tb_dump_switch(const struct tb *tb, const struct tb_switch *sw)
1287 {
1288 	const struct tb_regs_switch_header *regs = &sw->config;
1289 
1290 	tb_dbg(tb, " %s Switch: %x:%x (Revision: %d, TB Version: %d)\n",
1291 	       tb_switch_generation_name(sw), regs->vendor_id, regs->device_id,
1292 	       regs->revision, regs->thunderbolt_version);
1293 	tb_dbg(tb, "  Max Port Number: %d\n", regs->max_port_number);
1294 	tb_dbg(tb, "  Config:\n");
1295 	tb_dbg(tb,
1296 		"   Upstream Port Number: %d Depth: %d Route String: %#llx Enabled: %d, PlugEventsDelay: %dms\n",
1297 	       regs->upstream_port_number, regs->depth,
1298 	       (((u64) regs->route_hi) << 32) | regs->route_lo,
1299 	       regs->enabled, regs->plug_events_delay);
1300 	tb_dbg(tb, "   unknown1: %#x unknown4: %#x\n",
1301 	       regs->__unknown1, regs->__unknown4);
1302 }
1303 
1304 /**
1305  * reset_switch() - reconfigure route, enable and send TB_CFG_PKG_RESET
1306  * @sw: Switch to reset
1307  *
1308  * Return: Returns 0 on success or an error code on failure.
1309  */
1310 int tb_switch_reset(struct tb_switch *sw)
1311 {
1312 	struct tb_cfg_result res;
1313 
1314 	if (sw->generation > 1)
1315 		return 0;
1316 
1317 	tb_sw_dbg(sw, "resetting switch\n");
1318 
1319 	res.err = tb_sw_write(sw, ((u32 *) &sw->config) + 2,
1320 			      TB_CFG_SWITCH, 2, 2);
1321 	if (res.err)
1322 		return res.err;
1323 	res = tb_cfg_reset(sw->tb->ctl, tb_route(sw), TB_CFG_DEFAULT_TIMEOUT);
1324 	if (res.err > 0)
1325 		return -EIO;
1326 	return res.err;
1327 }
1328 
1329 /**
1330  * tb_plug_events_active() - enable/disable plug events on a switch
1331  *
1332  * Also configures a sane plug_events_delay of 255ms.
1333  *
1334  * Return: Returns 0 on success or an error code on failure.
1335  */
1336 static int tb_plug_events_active(struct tb_switch *sw, bool active)
1337 {
1338 	u32 data;
1339 	int res;
1340 
1341 	if (tb_switch_is_icm(sw) || tb_switch_is_usb4(sw))
1342 		return 0;
1343 
1344 	sw->config.plug_events_delay = 0xff;
1345 	res = tb_sw_write(sw, ((u32 *) &sw->config) + 4, TB_CFG_SWITCH, 4, 1);
1346 	if (res)
1347 		return res;
1348 
1349 	res = tb_sw_read(sw, &data, TB_CFG_SWITCH, sw->cap_plug_events + 1, 1);
1350 	if (res)
1351 		return res;
1352 
1353 	if (active) {
1354 		data = data & 0xFFFFFF83;
1355 		switch (sw->config.device_id) {
1356 		case PCI_DEVICE_ID_INTEL_LIGHT_RIDGE:
1357 		case PCI_DEVICE_ID_INTEL_EAGLE_RIDGE:
1358 		case PCI_DEVICE_ID_INTEL_PORT_RIDGE:
1359 			break;
1360 		default:
1361 			data |= 4;
1362 		}
1363 	} else {
1364 		data = data | 0x7c;
1365 	}
1366 	return tb_sw_write(sw, &data, TB_CFG_SWITCH,
1367 			   sw->cap_plug_events + 1, 1);
1368 }
1369 
1370 static ssize_t authorized_show(struct device *dev,
1371 			       struct device_attribute *attr,
1372 			       char *buf)
1373 {
1374 	struct tb_switch *sw = tb_to_switch(dev);
1375 
1376 	return sprintf(buf, "%u\n", sw->authorized);
1377 }
1378 
1379 static int tb_switch_set_authorized(struct tb_switch *sw, unsigned int val)
1380 {
1381 	int ret = -EINVAL;
1382 
1383 	if (!mutex_trylock(&sw->tb->lock))
1384 		return restart_syscall();
1385 
1386 	if (sw->authorized)
1387 		goto unlock;
1388 
1389 	switch (val) {
1390 	/* Approve switch */
1391 	case 1:
1392 		if (sw->key)
1393 			ret = tb_domain_approve_switch_key(sw->tb, sw);
1394 		else
1395 			ret = tb_domain_approve_switch(sw->tb, sw);
1396 		break;
1397 
1398 	/* Challenge switch */
1399 	case 2:
1400 		if (sw->key)
1401 			ret = tb_domain_challenge_switch_key(sw->tb, sw);
1402 		break;
1403 
1404 	default:
1405 		break;
1406 	}
1407 
1408 	if (!ret) {
1409 		sw->authorized = val;
1410 		/* Notify status change to the userspace */
1411 		kobject_uevent(&sw->dev.kobj, KOBJ_CHANGE);
1412 	}
1413 
1414 unlock:
1415 	mutex_unlock(&sw->tb->lock);
1416 	return ret;
1417 }
1418 
1419 static ssize_t authorized_store(struct device *dev,
1420 				struct device_attribute *attr,
1421 				const char *buf, size_t count)
1422 {
1423 	struct tb_switch *sw = tb_to_switch(dev);
1424 	unsigned int val;
1425 	ssize_t ret;
1426 
1427 	ret = kstrtouint(buf, 0, &val);
1428 	if (ret)
1429 		return ret;
1430 	if (val > 2)
1431 		return -EINVAL;
1432 
1433 	pm_runtime_get_sync(&sw->dev);
1434 	ret = tb_switch_set_authorized(sw, val);
1435 	pm_runtime_mark_last_busy(&sw->dev);
1436 	pm_runtime_put_autosuspend(&sw->dev);
1437 
1438 	return ret ? ret : count;
1439 }
1440 static DEVICE_ATTR_RW(authorized);
1441 
1442 static ssize_t boot_show(struct device *dev, struct device_attribute *attr,
1443 			 char *buf)
1444 {
1445 	struct tb_switch *sw = tb_to_switch(dev);
1446 
1447 	return sprintf(buf, "%u\n", sw->boot);
1448 }
1449 static DEVICE_ATTR_RO(boot);
1450 
1451 static ssize_t device_show(struct device *dev, struct device_attribute *attr,
1452 			   char *buf)
1453 {
1454 	struct tb_switch *sw = tb_to_switch(dev);
1455 
1456 	return sprintf(buf, "%#x\n", sw->device);
1457 }
1458 static DEVICE_ATTR_RO(device);
1459 
1460 static ssize_t
1461 device_name_show(struct device *dev, struct device_attribute *attr, char *buf)
1462 {
1463 	struct tb_switch *sw = tb_to_switch(dev);
1464 
1465 	return sprintf(buf, "%s\n", sw->device_name ? sw->device_name : "");
1466 }
1467 static DEVICE_ATTR_RO(device_name);
1468 
1469 static ssize_t
1470 generation_show(struct device *dev, struct device_attribute *attr, char *buf)
1471 {
1472 	struct tb_switch *sw = tb_to_switch(dev);
1473 
1474 	return sprintf(buf, "%u\n", sw->generation);
1475 }
1476 static DEVICE_ATTR_RO(generation);
1477 
1478 static ssize_t key_show(struct device *dev, struct device_attribute *attr,
1479 			char *buf)
1480 {
1481 	struct tb_switch *sw = tb_to_switch(dev);
1482 	ssize_t ret;
1483 
1484 	if (!mutex_trylock(&sw->tb->lock))
1485 		return restart_syscall();
1486 
1487 	if (sw->key)
1488 		ret = sprintf(buf, "%*phN\n", TB_SWITCH_KEY_SIZE, sw->key);
1489 	else
1490 		ret = sprintf(buf, "\n");
1491 
1492 	mutex_unlock(&sw->tb->lock);
1493 	return ret;
1494 }
1495 
1496 static ssize_t key_store(struct device *dev, struct device_attribute *attr,
1497 			 const char *buf, size_t count)
1498 {
1499 	struct tb_switch *sw = tb_to_switch(dev);
1500 	u8 key[TB_SWITCH_KEY_SIZE];
1501 	ssize_t ret = count;
1502 	bool clear = false;
1503 
1504 	if (!strcmp(buf, "\n"))
1505 		clear = true;
1506 	else if (hex2bin(key, buf, sizeof(key)))
1507 		return -EINVAL;
1508 
1509 	if (!mutex_trylock(&sw->tb->lock))
1510 		return restart_syscall();
1511 
1512 	if (sw->authorized) {
1513 		ret = -EBUSY;
1514 	} else {
1515 		kfree(sw->key);
1516 		if (clear) {
1517 			sw->key = NULL;
1518 		} else {
1519 			sw->key = kmemdup(key, sizeof(key), GFP_KERNEL);
1520 			if (!sw->key)
1521 				ret = -ENOMEM;
1522 		}
1523 	}
1524 
1525 	mutex_unlock(&sw->tb->lock);
1526 	return ret;
1527 }
1528 static DEVICE_ATTR(key, 0600, key_show, key_store);
1529 
1530 static ssize_t speed_show(struct device *dev, struct device_attribute *attr,
1531 			  char *buf)
1532 {
1533 	struct tb_switch *sw = tb_to_switch(dev);
1534 
1535 	return sprintf(buf, "%u.0 Gb/s\n", sw->link_speed);
1536 }
1537 
1538 /*
1539  * Currently all lanes must run at the same speed but we expose here
1540  * both directions to allow possible asymmetric links in the future.
1541  */
1542 static DEVICE_ATTR(rx_speed, 0444, speed_show, NULL);
1543 static DEVICE_ATTR(tx_speed, 0444, speed_show, NULL);
1544 
1545 static ssize_t lanes_show(struct device *dev, struct device_attribute *attr,
1546 			  char *buf)
1547 {
1548 	struct tb_switch *sw = tb_to_switch(dev);
1549 
1550 	return sprintf(buf, "%u\n", sw->link_width);
1551 }
1552 
1553 /*
1554  * Currently link has same amount of lanes both directions (1 or 2) but
1555  * expose them separately to allow possible asymmetric links in the future.
1556  */
1557 static DEVICE_ATTR(rx_lanes, 0444, lanes_show, NULL);
1558 static DEVICE_ATTR(tx_lanes, 0444, lanes_show, NULL);
1559 
1560 static ssize_t nvm_authenticate_show(struct device *dev,
1561 	struct device_attribute *attr, char *buf)
1562 {
1563 	struct tb_switch *sw = tb_to_switch(dev);
1564 	u32 status;
1565 
1566 	nvm_get_auth_status(sw, &status);
1567 	return sprintf(buf, "%#x\n", status);
1568 }
1569 
1570 static ssize_t nvm_authenticate_sysfs(struct device *dev, const char *buf,
1571 				      bool disconnect)
1572 {
1573 	struct tb_switch *sw = tb_to_switch(dev);
1574 	int val;
1575 	int ret;
1576 
1577 	pm_runtime_get_sync(&sw->dev);
1578 
1579 	if (!mutex_trylock(&sw->tb->lock)) {
1580 		ret = restart_syscall();
1581 		goto exit_rpm;
1582 	}
1583 
1584 	/* If NVMem devices are not yet added */
1585 	if (!sw->nvm) {
1586 		ret = -EAGAIN;
1587 		goto exit_unlock;
1588 	}
1589 
1590 	ret = kstrtoint(buf, 10, &val);
1591 	if (ret)
1592 		goto exit_unlock;
1593 
1594 	/* Always clear the authentication status */
1595 	nvm_clear_auth_status(sw);
1596 
1597 	if (val > 0) {
1598 		if (!sw->nvm->flushed) {
1599 			if (!sw->nvm->buf) {
1600 				ret = -EINVAL;
1601 				goto exit_unlock;
1602 			}
1603 
1604 			ret = nvm_validate_and_write(sw);
1605 			if (ret || val == WRITE_ONLY)
1606 				goto exit_unlock;
1607 		}
1608 		if (val == WRITE_AND_AUTHENTICATE) {
1609 			if (disconnect) {
1610 				ret = tb_lc_force_power(sw);
1611 			} else {
1612 				sw->nvm->authenticating = true;
1613 				ret = nvm_authenticate(sw);
1614 			}
1615 		}
1616 	}
1617 
1618 exit_unlock:
1619 	mutex_unlock(&sw->tb->lock);
1620 exit_rpm:
1621 	pm_runtime_mark_last_busy(&sw->dev);
1622 	pm_runtime_put_autosuspend(&sw->dev);
1623 
1624 	return ret;
1625 }
1626 
1627 static ssize_t nvm_authenticate_store(struct device *dev,
1628 	struct device_attribute *attr, const char *buf, size_t count)
1629 {
1630 	int ret = nvm_authenticate_sysfs(dev, buf, false);
1631 	if (ret)
1632 		return ret;
1633 	return count;
1634 }
1635 static DEVICE_ATTR_RW(nvm_authenticate);
1636 
1637 static ssize_t nvm_authenticate_on_disconnect_show(struct device *dev,
1638 	struct device_attribute *attr, char *buf)
1639 {
1640 	return nvm_authenticate_show(dev, attr, buf);
1641 }
1642 
1643 static ssize_t nvm_authenticate_on_disconnect_store(struct device *dev,
1644 	struct device_attribute *attr, const char *buf, size_t count)
1645 {
1646 	int ret;
1647 
1648 	ret = nvm_authenticate_sysfs(dev, buf, true);
1649 	return ret ? ret : count;
1650 }
1651 static DEVICE_ATTR_RW(nvm_authenticate_on_disconnect);
1652 
1653 static ssize_t nvm_version_show(struct device *dev,
1654 				struct device_attribute *attr, char *buf)
1655 {
1656 	struct tb_switch *sw = tb_to_switch(dev);
1657 	int ret;
1658 
1659 	if (!mutex_trylock(&sw->tb->lock))
1660 		return restart_syscall();
1661 
1662 	if (sw->safe_mode)
1663 		ret = -ENODATA;
1664 	else if (!sw->nvm)
1665 		ret = -EAGAIN;
1666 	else
1667 		ret = sprintf(buf, "%x.%x\n", sw->nvm->major, sw->nvm->minor);
1668 
1669 	mutex_unlock(&sw->tb->lock);
1670 
1671 	return ret;
1672 }
1673 static DEVICE_ATTR_RO(nvm_version);
1674 
1675 static ssize_t vendor_show(struct device *dev, struct device_attribute *attr,
1676 			   char *buf)
1677 {
1678 	struct tb_switch *sw = tb_to_switch(dev);
1679 
1680 	return sprintf(buf, "%#x\n", sw->vendor);
1681 }
1682 static DEVICE_ATTR_RO(vendor);
1683 
1684 static ssize_t
1685 vendor_name_show(struct device *dev, struct device_attribute *attr, char *buf)
1686 {
1687 	struct tb_switch *sw = tb_to_switch(dev);
1688 
1689 	return sprintf(buf, "%s\n", sw->vendor_name ? sw->vendor_name : "");
1690 }
1691 static DEVICE_ATTR_RO(vendor_name);
1692 
1693 static ssize_t unique_id_show(struct device *dev, struct device_attribute *attr,
1694 			      char *buf)
1695 {
1696 	struct tb_switch *sw = tb_to_switch(dev);
1697 
1698 	return sprintf(buf, "%pUb\n", sw->uuid);
1699 }
1700 static DEVICE_ATTR_RO(unique_id);
1701 
1702 static struct attribute *switch_attrs[] = {
1703 	&dev_attr_authorized.attr,
1704 	&dev_attr_boot.attr,
1705 	&dev_attr_device.attr,
1706 	&dev_attr_device_name.attr,
1707 	&dev_attr_generation.attr,
1708 	&dev_attr_key.attr,
1709 	&dev_attr_nvm_authenticate.attr,
1710 	&dev_attr_nvm_authenticate_on_disconnect.attr,
1711 	&dev_attr_nvm_version.attr,
1712 	&dev_attr_rx_speed.attr,
1713 	&dev_attr_rx_lanes.attr,
1714 	&dev_attr_tx_speed.attr,
1715 	&dev_attr_tx_lanes.attr,
1716 	&dev_attr_vendor.attr,
1717 	&dev_attr_vendor_name.attr,
1718 	&dev_attr_unique_id.attr,
1719 	NULL,
1720 };
1721 
1722 static umode_t switch_attr_is_visible(struct kobject *kobj,
1723 				      struct attribute *attr, int n)
1724 {
1725 	struct device *dev = kobj_to_dev(kobj);
1726 	struct tb_switch *sw = tb_to_switch(dev);
1727 
1728 	if (attr == &dev_attr_device.attr) {
1729 		if (!sw->device)
1730 			return 0;
1731 	} else if (attr == &dev_attr_device_name.attr) {
1732 		if (!sw->device_name)
1733 			return 0;
1734 	} else if (attr == &dev_attr_vendor.attr)  {
1735 		if (!sw->vendor)
1736 			return 0;
1737 	} else if (attr == &dev_attr_vendor_name.attr)  {
1738 		if (!sw->vendor_name)
1739 			return 0;
1740 	} else if (attr == &dev_attr_key.attr) {
1741 		if (tb_route(sw) &&
1742 		    sw->tb->security_level == TB_SECURITY_SECURE &&
1743 		    sw->security_level == TB_SECURITY_SECURE)
1744 			return attr->mode;
1745 		return 0;
1746 	} else if (attr == &dev_attr_rx_speed.attr ||
1747 		   attr == &dev_attr_rx_lanes.attr ||
1748 		   attr == &dev_attr_tx_speed.attr ||
1749 		   attr == &dev_attr_tx_lanes.attr) {
1750 		if (tb_route(sw))
1751 			return attr->mode;
1752 		return 0;
1753 	} else if (attr == &dev_attr_nvm_authenticate.attr) {
1754 		if (nvm_upgradeable(sw))
1755 			return attr->mode;
1756 		return 0;
1757 	} else if (attr == &dev_attr_nvm_version.attr) {
1758 		if (nvm_readable(sw))
1759 			return attr->mode;
1760 		return 0;
1761 	} else if (attr == &dev_attr_boot.attr) {
1762 		if (tb_route(sw))
1763 			return attr->mode;
1764 		return 0;
1765 	} else if (attr == &dev_attr_nvm_authenticate_on_disconnect.attr) {
1766 		if (sw->quirks & QUIRK_FORCE_POWER_LINK_CONTROLLER)
1767 			return attr->mode;
1768 		return 0;
1769 	}
1770 
1771 	return sw->safe_mode ? 0 : attr->mode;
1772 }
1773 
1774 static struct attribute_group switch_group = {
1775 	.is_visible = switch_attr_is_visible,
1776 	.attrs = switch_attrs,
1777 };
1778 
1779 static const struct attribute_group *switch_groups[] = {
1780 	&switch_group,
1781 	NULL,
1782 };
1783 
1784 static void tb_switch_release(struct device *dev)
1785 {
1786 	struct tb_switch *sw = tb_to_switch(dev);
1787 	struct tb_port *port;
1788 
1789 	dma_port_free(sw->dma_port);
1790 
1791 	tb_switch_for_each_port(sw, port) {
1792 		if (!port->disabled) {
1793 			ida_destroy(&port->in_hopids);
1794 			ida_destroy(&port->out_hopids);
1795 		}
1796 	}
1797 
1798 	kfree(sw->uuid);
1799 	kfree(sw->device_name);
1800 	kfree(sw->vendor_name);
1801 	kfree(sw->ports);
1802 	kfree(sw->drom);
1803 	kfree(sw->key);
1804 	kfree(sw);
1805 }
1806 
1807 /*
1808  * Currently only need to provide the callbacks. Everything else is handled
1809  * in the connection manager.
1810  */
1811 static int __maybe_unused tb_switch_runtime_suspend(struct device *dev)
1812 {
1813 	struct tb_switch *sw = tb_to_switch(dev);
1814 	const struct tb_cm_ops *cm_ops = sw->tb->cm_ops;
1815 
1816 	if (cm_ops->runtime_suspend_switch)
1817 		return cm_ops->runtime_suspend_switch(sw);
1818 
1819 	return 0;
1820 }
1821 
1822 static int __maybe_unused tb_switch_runtime_resume(struct device *dev)
1823 {
1824 	struct tb_switch *sw = tb_to_switch(dev);
1825 	const struct tb_cm_ops *cm_ops = sw->tb->cm_ops;
1826 
1827 	if (cm_ops->runtime_resume_switch)
1828 		return cm_ops->runtime_resume_switch(sw);
1829 	return 0;
1830 }
1831 
1832 static const struct dev_pm_ops tb_switch_pm_ops = {
1833 	SET_RUNTIME_PM_OPS(tb_switch_runtime_suspend, tb_switch_runtime_resume,
1834 			   NULL)
1835 };
1836 
1837 struct device_type tb_switch_type = {
1838 	.name = "thunderbolt_device",
1839 	.release = tb_switch_release,
1840 	.pm = &tb_switch_pm_ops,
1841 };
1842 
1843 static int tb_switch_get_generation(struct tb_switch *sw)
1844 {
1845 	switch (sw->config.device_id) {
1846 	case PCI_DEVICE_ID_INTEL_LIGHT_RIDGE:
1847 	case PCI_DEVICE_ID_INTEL_EAGLE_RIDGE:
1848 	case PCI_DEVICE_ID_INTEL_LIGHT_PEAK:
1849 	case PCI_DEVICE_ID_INTEL_CACTUS_RIDGE_2C:
1850 	case PCI_DEVICE_ID_INTEL_CACTUS_RIDGE_4C:
1851 	case PCI_DEVICE_ID_INTEL_PORT_RIDGE:
1852 	case PCI_DEVICE_ID_INTEL_REDWOOD_RIDGE_2C_BRIDGE:
1853 	case PCI_DEVICE_ID_INTEL_REDWOOD_RIDGE_4C_BRIDGE:
1854 		return 1;
1855 
1856 	case PCI_DEVICE_ID_INTEL_WIN_RIDGE_2C_BRIDGE:
1857 	case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_2C_BRIDGE:
1858 	case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_4C_BRIDGE:
1859 		return 2;
1860 
1861 	case PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_LP_BRIDGE:
1862 	case PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_2C_BRIDGE:
1863 	case PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_4C_BRIDGE:
1864 	case PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_C_2C_BRIDGE:
1865 	case PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_C_4C_BRIDGE:
1866 	case PCI_DEVICE_ID_INTEL_TITAN_RIDGE_2C_BRIDGE:
1867 	case PCI_DEVICE_ID_INTEL_TITAN_RIDGE_4C_BRIDGE:
1868 	case PCI_DEVICE_ID_INTEL_TITAN_RIDGE_DD_BRIDGE:
1869 	case PCI_DEVICE_ID_INTEL_ICL_NHI0:
1870 	case PCI_DEVICE_ID_INTEL_ICL_NHI1:
1871 		return 3;
1872 
1873 	default:
1874 		if (tb_switch_is_usb4(sw))
1875 			return 4;
1876 
1877 		/*
1878 		 * For unknown switches assume generation to be 1 to be
1879 		 * on the safe side.
1880 		 */
1881 		tb_sw_warn(sw, "unsupported switch device id %#x\n",
1882 			   sw->config.device_id);
1883 		return 1;
1884 	}
1885 }
1886 
1887 static bool tb_switch_exceeds_max_depth(const struct tb_switch *sw, int depth)
1888 {
1889 	int max_depth;
1890 
1891 	if (tb_switch_is_usb4(sw) ||
1892 	    (sw->tb->root_switch && tb_switch_is_usb4(sw->tb->root_switch)))
1893 		max_depth = USB4_SWITCH_MAX_DEPTH;
1894 	else
1895 		max_depth = TB_SWITCH_MAX_DEPTH;
1896 
1897 	return depth > max_depth;
1898 }
1899 
1900 /**
1901  * tb_switch_alloc() - allocate a switch
1902  * @tb: Pointer to the owning domain
1903  * @parent: Parent device for this switch
1904  * @route: Route string for this switch
1905  *
1906  * Allocates and initializes a switch. Will not upload configuration to
1907  * the switch. For that you need to call tb_switch_configure()
1908  * separately. The returned switch should be released by calling
1909  * tb_switch_put().
1910  *
1911  * Return: Pointer to the allocated switch or ERR_PTR() in case of
1912  * failure.
1913  */
1914 struct tb_switch *tb_switch_alloc(struct tb *tb, struct device *parent,
1915 				  u64 route)
1916 {
1917 	struct tb_switch *sw;
1918 	int upstream_port;
1919 	int i, ret, depth;
1920 
1921 	/* Unlock the downstream port so we can access the switch below */
1922 	if (route) {
1923 		struct tb_switch *parent_sw = tb_to_switch(parent);
1924 		struct tb_port *down;
1925 
1926 		down = tb_port_at(route, parent_sw);
1927 		tb_port_unlock(down);
1928 	}
1929 
1930 	depth = tb_route_length(route);
1931 
1932 	upstream_port = tb_cfg_get_upstream_port(tb->ctl, route);
1933 	if (upstream_port < 0)
1934 		return ERR_PTR(upstream_port);
1935 
1936 	sw = kzalloc(sizeof(*sw), GFP_KERNEL);
1937 	if (!sw)
1938 		return ERR_PTR(-ENOMEM);
1939 
1940 	sw->tb = tb;
1941 	ret = tb_cfg_read(tb->ctl, &sw->config, route, 0, TB_CFG_SWITCH, 0, 5);
1942 	if (ret)
1943 		goto err_free_sw_ports;
1944 
1945 	sw->generation = tb_switch_get_generation(sw);
1946 
1947 	tb_dbg(tb, "current switch config:\n");
1948 	tb_dump_switch(tb, sw);
1949 
1950 	/* configure switch */
1951 	sw->config.upstream_port_number = upstream_port;
1952 	sw->config.depth = depth;
1953 	sw->config.route_hi = upper_32_bits(route);
1954 	sw->config.route_lo = lower_32_bits(route);
1955 	sw->config.enabled = 0;
1956 
1957 	/* Make sure we do not exceed maximum topology limit */
1958 	if (tb_switch_exceeds_max_depth(sw, depth)) {
1959 		ret = -EADDRNOTAVAIL;
1960 		goto err_free_sw_ports;
1961 	}
1962 
1963 	/* initialize ports */
1964 	sw->ports = kcalloc(sw->config.max_port_number + 1, sizeof(*sw->ports),
1965 				GFP_KERNEL);
1966 	if (!sw->ports) {
1967 		ret = -ENOMEM;
1968 		goto err_free_sw_ports;
1969 	}
1970 
1971 	for (i = 0; i <= sw->config.max_port_number; i++) {
1972 		/* minimum setup for tb_find_cap and tb_drom_read to work */
1973 		sw->ports[i].sw = sw;
1974 		sw->ports[i].port = i;
1975 	}
1976 
1977 	ret = tb_switch_find_vse_cap(sw, TB_VSE_CAP_PLUG_EVENTS);
1978 	if (ret > 0)
1979 		sw->cap_plug_events = ret;
1980 
1981 	ret = tb_switch_find_vse_cap(sw, TB_VSE_CAP_LINK_CONTROLLER);
1982 	if (ret > 0)
1983 		sw->cap_lc = ret;
1984 
1985 	/* Root switch is always authorized */
1986 	if (!route)
1987 		sw->authorized = true;
1988 
1989 	device_initialize(&sw->dev);
1990 	sw->dev.parent = parent;
1991 	sw->dev.bus = &tb_bus_type;
1992 	sw->dev.type = &tb_switch_type;
1993 	sw->dev.groups = switch_groups;
1994 	dev_set_name(&sw->dev, "%u-%llx", tb->index, tb_route(sw));
1995 
1996 	return sw;
1997 
1998 err_free_sw_ports:
1999 	kfree(sw->ports);
2000 	kfree(sw);
2001 
2002 	return ERR_PTR(ret);
2003 }
2004 
2005 /**
2006  * tb_switch_alloc_safe_mode() - allocate a switch that is in safe mode
2007  * @tb: Pointer to the owning domain
2008  * @parent: Parent device for this switch
2009  * @route: Route string for this switch
2010  *
2011  * This creates a switch in safe mode. This means the switch pretty much
2012  * lacks all capabilities except DMA configuration port before it is
2013  * flashed with a valid NVM firmware.
2014  *
2015  * The returned switch must be released by calling tb_switch_put().
2016  *
2017  * Return: Pointer to the allocated switch or ERR_PTR() in case of failure
2018  */
2019 struct tb_switch *
2020 tb_switch_alloc_safe_mode(struct tb *tb, struct device *parent, u64 route)
2021 {
2022 	struct tb_switch *sw;
2023 
2024 	sw = kzalloc(sizeof(*sw), GFP_KERNEL);
2025 	if (!sw)
2026 		return ERR_PTR(-ENOMEM);
2027 
2028 	sw->tb = tb;
2029 	sw->config.depth = tb_route_length(route);
2030 	sw->config.route_hi = upper_32_bits(route);
2031 	sw->config.route_lo = lower_32_bits(route);
2032 	sw->safe_mode = true;
2033 
2034 	device_initialize(&sw->dev);
2035 	sw->dev.parent = parent;
2036 	sw->dev.bus = &tb_bus_type;
2037 	sw->dev.type = &tb_switch_type;
2038 	sw->dev.groups = switch_groups;
2039 	dev_set_name(&sw->dev, "%u-%llx", tb->index, tb_route(sw));
2040 
2041 	return sw;
2042 }
2043 
2044 /**
2045  * tb_switch_configure() - Uploads configuration to the switch
2046  * @sw: Switch to configure
2047  *
2048  * Call this function before the switch is added to the system. It will
2049  * upload configuration to the switch and makes it available for the
2050  * connection manager to use. Can be called to the switch again after
2051  * resume from low power states to re-initialize it.
2052  *
2053  * Return: %0 in case of success and negative errno in case of failure
2054  */
2055 int tb_switch_configure(struct tb_switch *sw)
2056 {
2057 	struct tb *tb = sw->tb;
2058 	u64 route;
2059 	int ret;
2060 
2061 	route = tb_route(sw);
2062 
2063 	tb_dbg(tb, "%s Switch at %#llx (depth: %d, up port: %d)\n",
2064 	       sw->config.enabled ? "restoring" : "initializing", route,
2065 	       tb_route_length(route), sw->config.upstream_port_number);
2066 
2067 	sw->config.enabled = 1;
2068 
2069 	if (tb_switch_is_usb4(sw)) {
2070 		/*
2071 		 * For USB4 devices, we need to program the CM version
2072 		 * accordingly so that it knows to expose all the
2073 		 * additional capabilities.
2074 		 */
2075 		sw->config.cmuv = USB4_VERSION_1_0;
2076 
2077 		/* Enumerate the switch */
2078 		ret = tb_sw_write(sw, (u32 *)&sw->config + 1, TB_CFG_SWITCH,
2079 				  ROUTER_CS_1, 4);
2080 		if (ret)
2081 			return ret;
2082 
2083 		ret = usb4_switch_setup(sw);
2084 	} else {
2085 		if (sw->config.vendor_id != PCI_VENDOR_ID_INTEL)
2086 			tb_sw_warn(sw, "unknown switch vendor id %#x\n",
2087 				   sw->config.vendor_id);
2088 
2089 		if (!sw->cap_plug_events) {
2090 			tb_sw_warn(sw, "cannot find TB_VSE_CAP_PLUG_EVENTS aborting\n");
2091 			return -ENODEV;
2092 		}
2093 
2094 		/* Enumerate the switch */
2095 		ret = tb_sw_write(sw, (u32 *)&sw->config + 1, TB_CFG_SWITCH,
2096 				  ROUTER_CS_1, 3);
2097 	}
2098 	if (ret)
2099 		return ret;
2100 
2101 	return tb_plug_events_active(sw, true);
2102 }
2103 
2104 static int tb_switch_set_uuid(struct tb_switch *sw)
2105 {
2106 	bool uid = false;
2107 	u32 uuid[4];
2108 	int ret;
2109 
2110 	if (sw->uuid)
2111 		return 0;
2112 
2113 	if (tb_switch_is_usb4(sw)) {
2114 		ret = usb4_switch_read_uid(sw, &sw->uid);
2115 		if (ret)
2116 			return ret;
2117 		uid = true;
2118 	} else {
2119 		/*
2120 		 * The newer controllers include fused UUID as part of
2121 		 * link controller specific registers
2122 		 */
2123 		ret = tb_lc_read_uuid(sw, uuid);
2124 		if (ret) {
2125 			if (ret != -EINVAL)
2126 				return ret;
2127 			uid = true;
2128 		}
2129 	}
2130 
2131 	if (uid) {
2132 		/*
2133 		 * ICM generates UUID based on UID and fills the upper
2134 		 * two words with ones. This is not strictly following
2135 		 * UUID format but we want to be compatible with it so
2136 		 * we do the same here.
2137 		 */
2138 		uuid[0] = sw->uid & 0xffffffff;
2139 		uuid[1] = (sw->uid >> 32) & 0xffffffff;
2140 		uuid[2] = 0xffffffff;
2141 		uuid[3] = 0xffffffff;
2142 	}
2143 
2144 	sw->uuid = kmemdup(uuid, sizeof(uuid), GFP_KERNEL);
2145 	if (!sw->uuid)
2146 		return -ENOMEM;
2147 	return 0;
2148 }
2149 
2150 static int tb_switch_add_dma_port(struct tb_switch *sw)
2151 {
2152 	u32 status;
2153 	int ret;
2154 
2155 	switch (sw->generation) {
2156 	case 2:
2157 		/* Only root switch can be upgraded */
2158 		if (tb_route(sw))
2159 			return 0;
2160 
2161 		fallthrough;
2162 	case 3:
2163 	case 4:
2164 		ret = tb_switch_set_uuid(sw);
2165 		if (ret)
2166 			return ret;
2167 		break;
2168 
2169 	default:
2170 		/*
2171 		 * DMA port is the only thing available when the switch
2172 		 * is in safe mode.
2173 		 */
2174 		if (!sw->safe_mode)
2175 			return 0;
2176 		break;
2177 	}
2178 
2179 	if (sw->no_nvm_upgrade)
2180 		return 0;
2181 
2182 	if (tb_switch_is_usb4(sw)) {
2183 		ret = usb4_switch_nvm_authenticate_status(sw, &status);
2184 		if (ret)
2185 			return ret;
2186 
2187 		if (status) {
2188 			tb_sw_info(sw, "switch flash authentication failed\n");
2189 			nvm_set_auth_status(sw, status);
2190 		}
2191 
2192 		return 0;
2193 	}
2194 
2195 	/* Root switch DMA port requires running firmware */
2196 	if (!tb_route(sw) && !tb_switch_is_icm(sw))
2197 		return 0;
2198 
2199 	sw->dma_port = dma_port_alloc(sw);
2200 	if (!sw->dma_port)
2201 		return 0;
2202 
2203 	/*
2204 	 * If there is status already set then authentication failed
2205 	 * when the dma_port_flash_update_auth() returned. Power cycling
2206 	 * is not needed (it was done already) so only thing we do here
2207 	 * is to unblock runtime PM of the root port.
2208 	 */
2209 	nvm_get_auth_status(sw, &status);
2210 	if (status) {
2211 		if (!tb_route(sw))
2212 			nvm_authenticate_complete_dma_port(sw);
2213 		return 0;
2214 	}
2215 
2216 	/*
2217 	 * Check status of the previous flash authentication. If there
2218 	 * is one we need to power cycle the switch in any case to make
2219 	 * it functional again.
2220 	 */
2221 	ret = dma_port_flash_update_auth_status(sw->dma_port, &status);
2222 	if (ret <= 0)
2223 		return ret;
2224 
2225 	/* Now we can allow root port to suspend again */
2226 	if (!tb_route(sw))
2227 		nvm_authenticate_complete_dma_port(sw);
2228 
2229 	if (status) {
2230 		tb_sw_info(sw, "switch flash authentication failed\n");
2231 		nvm_set_auth_status(sw, status);
2232 	}
2233 
2234 	tb_sw_info(sw, "power cycling the switch now\n");
2235 	dma_port_power_cycle(sw->dma_port);
2236 
2237 	/*
2238 	 * We return error here which causes the switch adding failure.
2239 	 * It should appear back after power cycle is complete.
2240 	 */
2241 	return -ESHUTDOWN;
2242 }
2243 
2244 static void tb_switch_default_link_ports(struct tb_switch *sw)
2245 {
2246 	int i;
2247 
2248 	for (i = 1; i <= sw->config.max_port_number; i += 2) {
2249 		struct tb_port *port = &sw->ports[i];
2250 		struct tb_port *subordinate;
2251 
2252 		if (!tb_port_is_null(port))
2253 			continue;
2254 
2255 		/* Check for the subordinate port */
2256 		if (i == sw->config.max_port_number ||
2257 		    !tb_port_is_null(&sw->ports[i + 1]))
2258 			continue;
2259 
2260 		/* Link them if not already done so (by DROM) */
2261 		subordinate = &sw->ports[i + 1];
2262 		if (!port->dual_link_port && !subordinate->dual_link_port) {
2263 			port->link_nr = 0;
2264 			port->dual_link_port = subordinate;
2265 			subordinate->link_nr = 1;
2266 			subordinate->dual_link_port = port;
2267 
2268 			tb_sw_dbg(sw, "linked ports %d <-> %d\n",
2269 				  port->port, subordinate->port);
2270 		}
2271 	}
2272 }
2273 
2274 static bool tb_switch_lane_bonding_possible(struct tb_switch *sw)
2275 {
2276 	const struct tb_port *up = tb_upstream_port(sw);
2277 
2278 	if (!up->dual_link_port || !up->dual_link_port->remote)
2279 		return false;
2280 
2281 	if (tb_switch_is_usb4(sw))
2282 		return usb4_switch_lane_bonding_possible(sw);
2283 	return tb_lc_lane_bonding_possible(sw);
2284 }
2285 
2286 static int tb_switch_update_link_attributes(struct tb_switch *sw)
2287 {
2288 	struct tb_port *up;
2289 	bool change = false;
2290 	int ret;
2291 
2292 	if (!tb_route(sw) || tb_switch_is_icm(sw))
2293 		return 0;
2294 
2295 	up = tb_upstream_port(sw);
2296 
2297 	ret = tb_port_get_link_speed(up);
2298 	if (ret < 0)
2299 		return ret;
2300 	if (sw->link_speed != ret)
2301 		change = true;
2302 	sw->link_speed = ret;
2303 
2304 	ret = tb_port_get_link_width(up);
2305 	if (ret < 0)
2306 		return ret;
2307 	if (sw->link_width != ret)
2308 		change = true;
2309 	sw->link_width = ret;
2310 
2311 	/* Notify userspace that there is possible link attribute change */
2312 	if (device_is_registered(&sw->dev) && change)
2313 		kobject_uevent(&sw->dev.kobj, KOBJ_CHANGE);
2314 
2315 	return 0;
2316 }
2317 
2318 /**
2319  * tb_switch_lane_bonding_enable() - Enable lane bonding
2320  * @sw: Switch to enable lane bonding
2321  *
2322  * Connection manager can call this function to enable lane bonding of a
2323  * switch. If conditions are correct and both switches support the feature,
2324  * lanes are bonded. It is safe to call this to any switch.
2325  */
2326 int tb_switch_lane_bonding_enable(struct tb_switch *sw)
2327 {
2328 	struct tb_switch *parent = tb_to_switch(sw->dev.parent);
2329 	struct tb_port *up, *down;
2330 	u64 route = tb_route(sw);
2331 	int ret;
2332 
2333 	if (!route)
2334 		return 0;
2335 
2336 	if (!tb_switch_lane_bonding_possible(sw))
2337 		return 0;
2338 
2339 	up = tb_upstream_port(sw);
2340 	down = tb_port_at(route, parent);
2341 
2342 	if (!tb_port_is_width_supported(up, 2) ||
2343 	    !tb_port_is_width_supported(down, 2))
2344 		return 0;
2345 
2346 	ret = tb_port_lane_bonding_enable(up);
2347 	if (ret) {
2348 		tb_port_warn(up, "failed to enable lane bonding\n");
2349 		return ret;
2350 	}
2351 
2352 	ret = tb_port_lane_bonding_enable(down);
2353 	if (ret) {
2354 		tb_port_warn(down, "failed to enable lane bonding\n");
2355 		tb_port_lane_bonding_disable(up);
2356 		return ret;
2357 	}
2358 
2359 	tb_switch_update_link_attributes(sw);
2360 
2361 	tb_sw_dbg(sw, "lane bonding enabled\n");
2362 	return ret;
2363 }
2364 
2365 /**
2366  * tb_switch_lane_bonding_disable() - Disable lane bonding
2367  * @sw: Switch whose lane bonding to disable
2368  *
2369  * Disables lane bonding between @sw and parent. This can be called even
2370  * if lanes were not bonded originally.
2371  */
2372 void tb_switch_lane_bonding_disable(struct tb_switch *sw)
2373 {
2374 	struct tb_switch *parent = tb_to_switch(sw->dev.parent);
2375 	struct tb_port *up, *down;
2376 
2377 	if (!tb_route(sw))
2378 		return;
2379 
2380 	up = tb_upstream_port(sw);
2381 	if (!up->bonded)
2382 		return;
2383 
2384 	down = tb_port_at(tb_route(sw), parent);
2385 
2386 	tb_port_lane_bonding_disable(up);
2387 	tb_port_lane_bonding_disable(down);
2388 
2389 	tb_switch_update_link_attributes(sw);
2390 	tb_sw_dbg(sw, "lane bonding disabled\n");
2391 }
2392 
2393 /**
2394  * tb_switch_configure_link() - Set link configured
2395  * @sw: Switch whose link is configured
2396  *
2397  * Sets the link upstream from @sw configured (from both ends) so that
2398  * it will not be disconnected when the domain exits sleep. Can be
2399  * called for any switch.
2400  *
2401  * It is recommended that this is called after lane bonding is enabled.
2402  *
2403  * Returns %0 on success and negative errno in case of error.
2404  */
2405 int tb_switch_configure_link(struct tb_switch *sw)
2406 {
2407 	struct tb_port *up, *down;
2408 	int ret;
2409 
2410 	if (!tb_route(sw) || tb_switch_is_icm(sw))
2411 		return 0;
2412 
2413 	up = tb_upstream_port(sw);
2414 	if (tb_switch_is_usb4(up->sw))
2415 		ret = usb4_port_configure(up);
2416 	else
2417 		ret = tb_lc_configure_port(up);
2418 	if (ret)
2419 		return ret;
2420 
2421 	down = up->remote;
2422 	if (tb_switch_is_usb4(down->sw))
2423 		return usb4_port_configure(down);
2424 	return tb_lc_configure_port(down);
2425 }
2426 
2427 /**
2428  * tb_switch_unconfigure_link() - Unconfigure link
2429  * @sw: Switch whose link is unconfigured
2430  *
2431  * Sets the link unconfigured so the @sw will be disconnected if the
2432  * domain exists sleep.
2433  */
2434 void tb_switch_unconfigure_link(struct tb_switch *sw)
2435 {
2436 	struct tb_port *up, *down;
2437 
2438 	if (sw->is_unplugged)
2439 		return;
2440 	if (!tb_route(sw) || tb_switch_is_icm(sw))
2441 		return;
2442 
2443 	up = tb_upstream_port(sw);
2444 	if (tb_switch_is_usb4(up->sw))
2445 		usb4_port_unconfigure(up);
2446 	else
2447 		tb_lc_unconfigure_port(up);
2448 
2449 	down = up->remote;
2450 	if (tb_switch_is_usb4(down->sw))
2451 		usb4_port_unconfigure(down);
2452 	else
2453 		tb_lc_unconfigure_port(down);
2454 }
2455 
2456 /**
2457  * tb_switch_add() - Add a switch to the domain
2458  * @sw: Switch to add
2459  *
2460  * This is the last step in adding switch to the domain. It will read
2461  * identification information from DROM and initializes ports so that
2462  * they can be used to connect other switches. The switch will be
2463  * exposed to the userspace when this function successfully returns. To
2464  * remove and release the switch, call tb_switch_remove().
2465  *
2466  * Return: %0 in case of success and negative errno in case of failure
2467  */
2468 int tb_switch_add(struct tb_switch *sw)
2469 {
2470 	int i, ret;
2471 
2472 	/*
2473 	 * Initialize DMA control port now before we read DROM. Recent
2474 	 * host controllers have more complete DROM on NVM that includes
2475 	 * vendor and model identification strings which we then expose
2476 	 * to the userspace. NVM can be accessed through DMA
2477 	 * configuration based mailbox.
2478 	 */
2479 	ret = tb_switch_add_dma_port(sw);
2480 	if (ret) {
2481 		dev_err(&sw->dev, "failed to add DMA port\n");
2482 		return ret;
2483 	}
2484 
2485 	if (!sw->safe_mode) {
2486 		/* read drom */
2487 		ret = tb_drom_read(sw);
2488 		if (ret) {
2489 			dev_err(&sw->dev, "reading DROM failed\n");
2490 			return ret;
2491 		}
2492 		tb_sw_dbg(sw, "uid: %#llx\n", sw->uid);
2493 
2494 		ret = tb_switch_set_uuid(sw);
2495 		if (ret) {
2496 			dev_err(&sw->dev, "failed to set UUID\n");
2497 			return ret;
2498 		}
2499 
2500 		for (i = 0; i <= sw->config.max_port_number; i++) {
2501 			if (sw->ports[i].disabled) {
2502 				tb_port_dbg(&sw->ports[i], "disabled by eeprom\n");
2503 				continue;
2504 			}
2505 			ret = tb_init_port(&sw->ports[i]);
2506 			if (ret) {
2507 				dev_err(&sw->dev, "failed to initialize port %d\n", i);
2508 				return ret;
2509 			}
2510 		}
2511 
2512 		tb_switch_default_link_ports(sw);
2513 
2514 		ret = tb_switch_update_link_attributes(sw);
2515 		if (ret)
2516 			return ret;
2517 
2518 		ret = tb_switch_tmu_init(sw);
2519 		if (ret)
2520 			return ret;
2521 	}
2522 
2523 	ret = device_add(&sw->dev);
2524 	if (ret) {
2525 		dev_err(&sw->dev, "failed to add device: %d\n", ret);
2526 		return ret;
2527 	}
2528 
2529 	if (tb_route(sw)) {
2530 		dev_info(&sw->dev, "new device found, vendor=%#x device=%#x\n",
2531 			 sw->vendor, sw->device);
2532 		if (sw->vendor_name && sw->device_name)
2533 			dev_info(&sw->dev, "%s %s\n", sw->vendor_name,
2534 				 sw->device_name);
2535 	}
2536 
2537 	ret = tb_switch_nvm_add(sw);
2538 	if (ret) {
2539 		dev_err(&sw->dev, "failed to add NVM devices\n");
2540 		device_del(&sw->dev);
2541 		return ret;
2542 	}
2543 
2544 	/*
2545 	 * Thunderbolt routers do not generate wakeups themselves but
2546 	 * they forward wakeups from tunneled protocols, so enable it
2547 	 * here.
2548 	 */
2549 	device_init_wakeup(&sw->dev, true);
2550 
2551 	pm_runtime_set_active(&sw->dev);
2552 	if (sw->rpm) {
2553 		pm_runtime_set_autosuspend_delay(&sw->dev, TB_AUTOSUSPEND_DELAY);
2554 		pm_runtime_use_autosuspend(&sw->dev);
2555 		pm_runtime_mark_last_busy(&sw->dev);
2556 		pm_runtime_enable(&sw->dev);
2557 		pm_request_autosuspend(&sw->dev);
2558 	}
2559 
2560 	tb_switch_debugfs_init(sw);
2561 	return 0;
2562 }
2563 
2564 /**
2565  * tb_switch_remove() - Remove and release a switch
2566  * @sw: Switch to remove
2567  *
2568  * This will remove the switch from the domain and release it after last
2569  * reference count drops to zero. If there are switches connected below
2570  * this switch, they will be removed as well.
2571  */
2572 void tb_switch_remove(struct tb_switch *sw)
2573 {
2574 	struct tb_port *port;
2575 
2576 	tb_switch_debugfs_remove(sw);
2577 
2578 	if (sw->rpm) {
2579 		pm_runtime_get_sync(&sw->dev);
2580 		pm_runtime_disable(&sw->dev);
2581 	}
2582 
2583 	/* port 0 is the switch itself and never has a remote */
2584 	tb_switch_for_each_port(sw, port) {
2585 		if (tb_port_has_remote(port)) {
2586 			tb_switch_remove(port->remote->sw);
2587 			port->remote = NULL;
2588 		} else if (port->xdomain) {
2589 			tb_xdomain_remove(port->xdomain);
2590 			port->xdomain = NULL;
2591 		}
2592 
2593 		/* Remove any downstream retimers */
2594 		tb_retimer_remove_all(port);
2595 	}
2596 
2597 	if (!sw->is_unplugged)
2598 		tb_plug_events_active(sw, false);
2599 
2600 	tb_switch_nvm_remove(sw);
2601 
2602 	if (tb_route(sw))
2603 		dev_info(&sw->dev, "device disconnected\n");
2604 	device_unregister(&sw->dev);
2605 }
2606 
2607 /**
2608  * tb_sw_set_unplugged() - set is_unplugged on switch and downstream switches
2609  */
2610 void tb_sw_set_unplugged(struct tb_switch *sw)
2611 {
2612 	struct tb_port *port;
2613 
2614 	if (sw == sw->tb->root_switch) {
2615 		tb_sw_WARN(sw, "cannot unplug root switch\n");
2616 		return;
2617 	}
2618 	if (sw->is_unplugged) {
2619 		tb_sw_WARN(sw, "is_unplugged already set\n");
2620 		return;
2621 	}
2622 	sw->is_unplugged = true;
2623 	tb_switch_for_each_port(sw, port) {
2624 		if (tb_port_has_remote(port))
2625 			tb_sw_set_unplugged(port->remote->sw);
2626 		else if (port->xdomain)
2627 			port->xdomain->is_unplugged = true;
2628 	}
2629 }
2630 
2631 static int tb_switch_set_wake(struct tb_switch *sw, unsigned int flags)
2632 {
2633 	if (flags)
2634 		tb_sw_dbg(sw, "enabling wakeup: %#x\n", flags);
2635 	else
2636 		tb_sw_dbg(sw, "disabling wakeup\n");
2637 
2638 	if (tb_switch_is_usb4(sw))
2639 		return usb4_switch_set_wake(sw, flags);
2640 	return tb_lc_set_wake(sw, flags);
2641 }
2642 
2643 int tb_switch_resume(struct tb_switch *sw)
2644 {
2645 	struct tb_port *port;
2646 	int err;
2647 
2648 	tb_sw_dbg(sw, "resuming switch\n");
2649 
2650 	/*
2651 	 * Check for UID of the connected switches except for root
2652 	 * switch which we assume cannot be removed.
2653 	 */
2654 	if (tb_route(sw)) {
2655 		u64 uid;
2656 
2657 		/*
2658 		 * Check first that we can still read the switch config
2659 		 * space. It may be that there is now another domain
2660 		 * connected.
2661 		 */
2662 		err = tb_cfg_get_upstream_port(sw->tb->ctl, tb_route(sw));
2663 		if (err < 0) {
2664 			tb_sw_info(sw, "switch not present anymore\n");
2665 			return err;
2666 		}
2667 
2668 		if (tb_switch_is_usb4(sw))
2669 			err = usb4_switch_read_uid(sw, &uid);
2670 		else
2671 			err = tb_drom_read_uid_only(sw, &uid);
2672 		if (err) {
2673 			tb_sw_warn(sw, "uid read failed\n");
2674 			return err;
2675 		}
2676 		if (sw->uid != uid) {
2677 			tb_sw_info(sw,
2678 				"changed while suspended (uid %#llx -> %#llx)\n",
2679 				sw->uid, uid);
2680 			return -ENODEV;
2681 		}
2682 	}
2683 
2684 	err = tb_switch_configure(sw);
2685 	if (err)
2686 		return err;
2687 
2688 	/* Disable wakes */
2689 	tb_switch_set_wake(sw, 0);
2690 
2691 	err = tb_switch_tmu_init(sw);
2692 	if (err)
2693 		return err;
2694 
2695 	/* check for surviving downstream switches */
2696 	tb_switch_for_each_port(sw, port) {
2697 		if (!tb_port_has_remote(port) && !port->xdomain)
2698 			continue;
2699 
2700 		if (tb_wait_for_port(port, true) <= 0) {
2701 			tb_port_warn(port,
2702 				     "lost during suspend, disconnecting\n");
2703 			if (tb_port_has_remote(port))
2704 				tb_sw_set_unplugged(port->remote->sw);
2705 			else if (port->xdomain)
2706 				port->xdomain->is_unplugged = true;
2707 		} else if (tb_port_has_remote(port) || port->xdomain) {
2708 			/*
2709 			 * Always unlock the port so the downstream
2710 			 * switch/domain is accessible.
2711 			 */
2712 			if (tb_port_unlock(port))
2713 				tb_port_warn(port, "failed to unlock port\n");
2714 			if (port->remote && tb_switch_resume(port->remote->sw)) {
2715 				tb_port_warn(port,
2716 					     "lost during suspend, disconnecting\n");
2717 				tb_sw_set_unplugged(port->remote->sw);
2718 			}
2719 		}
2720 	}
2721 	return 0;
2722 }
2723 
2724 /**
2725  * tb_switch_suspend() - Put a switch to sleep
2726  * @sw: Switch to suspend
2727  * @runtime: Is this runtime suspend or system sleep
2728  *
2729  * Suspends router and all its children. Enables wakes according to
2730  * value of @runtime and then sets sleep bit for the router. If @sw is
2731  * host router the domain is ready to go to sleep once this function
2732  * returns.
2733  */
2734 void tb_switch_suspend(struct tb_switch *sw, bool runtime)
2735 {
2736 	unsigned int flags = 0;
2737 	struct tb_port *port;
2738 	int err;
2739 
2740 	tb_sw_dbg(sw, "suspending switch\n");
2741 
2742 	err = tb_plug_events_active(sw, false);
2743 	if (err)
2744 		return;
2745 
2746 	tb_switch_for_each_port(sw, port) {
2747 		if (tb_port_has_remote(port))
2748 			tb_switch_suspend(port->remote->sw, runtime);
2749 	}
2750 
2751 	if (runtime) {
2752 		/* Trigger wake when something is plugged in/out */
2753 		flags |= TB_WAKE_ON_CONNECT | TB_WAKE_ON_DISCONNECT;
2754 		flags |= TB_WAKE_ON_USB4 | TB_WAKE_ON_USB3 | TB_WAKE_ON_PCIE;
2755 	} else if (device_may_wakeup(&sw->dev)) {
2756 		flags |= TB_WAKE_ON_USB4 | TB_WAKE_ON_USB3 | TB_WAKE_ON_PCIE;
2757 	}
2758 
2759 	tb_switch_set_wake(sw, flags);
2760 
2761 	if (tb_switch_is_usb4(sw))
2762 		usb4_switch_set_sleep(sw);
2763 	else
2764 		tb_lc_set_sleep(sw);
2765 }
2766 
2767 /**
2768  * tb_switch_query_dp_resource() - Query availability of DP resource
2769  * @sw: Switch whose DP resource is queried
2770  * @in: DP IN port
2771  *
2772  * Queries availability of DP resource for DP tunneling using switch
2773  * specific means. Returns %true if resource is available.
2774  */
2775 bool tb_switch_query_dp_resource(struct tb_switch *sw, struct tb_port *in)
2776 {
2777 	if (tb_switch_is_usb4(sw))
2778 		return usb4_switch_query_dp_resource(sw, in);
2779 	return tb_lc_dp_sink_query(sw, in);
2780 }
2781 
2782 /**
2783  * tb_switch_alloc_dp_resource() - Allocate available DP resource
2784  * @sw: Switch whose DP resource is allocated
2785  * @in: DP IN port
2786  *
2787  * Allocates DP resource for DP tunneling. The resource must be
2788  * available for this to succeed (see tb_switch_query_dp_resource()).
2789  * Returns %0 in success and negative errno otherwise.
2790  */
2791 int tb_switch_alloc_dp_resource(struct tb_switch *sw, struct tb_port *in)
2792 {
2793 	if (tb_switch_is_usb4(sw))
2794 		return usb4_switch_alloc_dp_resource(sw, in);
2795 	return tb_lc_dp_sink_alloc(sw, in);
2796 }
2797 
2798 /**
2799  * tb_switch_dealloc_dp_resource() - De-allocate DP resource
2800  * @sw: Switch whose DP resource is de-allocated
2801  * @in: DP IN port
2802  *
2803  * De-allocates DP resource that was previously allocated for DP
2804  * tunneling.
2805  */
2806 void tb_switch_dealloc_dp_resource(struct tb_switch *sw, struct tb_port *in)
2807 {
2808 	int ret;
2809 
2810 	if (tb_switch_is_usb4(sw))
2811 		ret = usb4_switch_dealloc_dp_resource(sw, in);
2812 	else
2813 		ret = tb_lc_dp_sink_dealloc(sw, in);
2814 
2815 	if (ret)
2816 		tb_sw_warn(sw, "failed to de-allocate DP resource for port %d\n",
2817 			   in->port);
2818 }
2819 
2820 struct tb_sw_lookup {
2821 	struct tb *tb;
2822 	u8 link;
2823 	u8 depth;
2824 	const uuid_t *uuid;
2825 	u64 route;
2826 };
2827 
2828 static int tb_switch_match(struct device *dev, const void *data)
2829 {
2830 	struct tb_switch *sw = tb_to_switch(dev);
2831 	const struct tb_sw_lookup *lookup = data;
2832 
2833 	if (!sw)
2834 		return 0;
2835 	if (sw->tb != lookup->tb)
2836 		return 0;
2837 
2838 	if (lookup->uuid)
2839 		return !memcmp(sw->uuid, lookup->uuid, sizeof(*lookup->uuid));
2840 
2841 	if (lookup->route) {
2842 		return sw->config.route_lo == lower_32_bits(lookup->route) &&
2843 		       sw->config.route_hi == upper_32_bits(lookup->route);
2844 	}
2845 
2846 	/* Root switch is matched only by depth */
2847 	if (!lookup->depth)
2848 		return !sw->depth;
2849 
2850 	return sw->link == lookup->link && sw->depth == lookup->depth;
2851 }
2852 
2853 /**
2854  * tb_switch_find_by_link_depth() - Find switch by link and depth
2855  * @tb: Domain the switch belongs
2856  * @link: Link number the switch is connected
2857  * @depth: Depth of the switch in link
2858  *
2859  * Returned switch has reference count increased so the caller needs to
2860  * call tb_switch_put() when done with the switch.
2861  */
2862 struct tb_switch *tb_switch_find_by_link_depth(struct tb *tb, u8 link, u8 depth)
2863 {
2864 	struct tb_sw_lookup lookup;
2865 	struct device *dev;
2866 
2867 	memset(&lookup, 0, sizeof(lookup));
2868 	lookup.tb = tb;
2869 	lookup.link = link;
2870 	lookup.depth = depth;
2871 
2872 	dev = bus_find_device(&tb_bus_type, NULL, &lookup, tb_switch_match);
2873 	if (dev)
2874 		return tb_to_switch(dev);
2875 
2876 	return NULL;
2877 }
2878 
2879 /**
2880  * tb_switch_find_by_uuid() - Find switch by UUID
2881  * @tb: Domain the switch belongs
2882  * @uuid: UUID to look for
2883  *
2884  * Returned switch has reference count increased so the caller needs to
2885  * call tb_switch_put() when done with the switch.
2886  */
2887 struct tb_switch *tb_switch_find_by_uuid(struct tb *tb, const uuid_t *uuid)
2888 {
2889 	struct tb_sw_lookup lookup;
2890 	struct device *dev;
2891 
2892 	memset(&lookup, 0, sizeof(lookup));
2893 	lookup.tb = tb;
2894 	lookup.uuid = uuid;
2895 
2896 	dev = bus_find_device(&tb_bus_type, NULL, &lookup, tb_switch_match);
2897 	if (dev)
2898 		return tb_to_switch(dev);
2899 
2900 	return NULL;
2901 }
2902 
2903 /**
2904  * tb_switch_find_by_route() - Find switch by route string
2905  * @tb: Domain the switch belongs
2906  * @route: Route string to look for
2907  *
2908  * Returned switch has reference count increased so the caller needs to
2909  * call tb_switch_put() when done with the switch.
2910  */
2911 struct tb_switch *tb_switch_find_by_route(struct tb *tb, u64 route)
2912 {
2913 	struct tb_sw_lookup lookup;
2914 	struct device *dev;
2915 
2916 	if (!route)
2917 		return tb_switch_get(tb->root_switch);
2918 
2919 	memset(&lookup, 0, sizeof(lookup));
2920 	lookup.tb = tb;
2921 	lookup.route = route;
2922 
2923 	dev = bus_find_device(&tb_bus_type, NULL, &lookup, tb_switch_match);
2924 	if (dev)
2925 		return tb_to_switch(dev);
2926 
2927 	return NULL;
2928 }
2929 
2930 /**
2931  * tb_switch_find_port() - return the first port of @type on @sw or NULL
2932  * @sw: Switch to find the port from
2933  * @type: Port type to look for
2934  */
2935 struct tb_port *tb_switch_find_port(struct tb_switch *sw,
2936 				    enum tb_port_type type)
2937 {
2938 	struct tb_port *port;
2939 
2940 	tb_switch_for_each_port(sw, port) {
2941 		if (port->config.type == type)
2942 			return port;
2943 	}
2944 
2945 	return NULL;
2946 }
2947