xref: /linux/drivers/usb/usbip/vhci_hcd.c (revision 87c9c16317882dd6dbbc07e349bc3223e14f3244)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2003-2008 Takahiro Hirofuchi
4  * Copyright (C) 2015-2016 Nobuo Iwata
5  */
6 
7 #include <linux/init.h>
8 #include <linux/file.h>
9 #include <linux/kernel.h>
10 #include <linux/kthread.h>
11 #include <linux/module.h>
12 #include <linux/platform_device.h>
13 #include <linux/slab.h>
14 
15 #include "usbip_common.h"
16 #include "vhci.h"
17 
18 #define DRIVER_AUTHOR "Takahiro Hirofuchi"
19 #define DRIVER_DESC "USB/IP 'Virtual' Host Controller (VHCI) Driver"
20 
21 /*
22  * TODO
23  *	- update root hub emulation
24  *	- move the emulation code to userland ?
25  *		porting to other operating systems
26  *		minimize kernel code
27  *	- add suspend/resume code
28  *	- clean up everything
29  */
30 
31 /* See usb gadget dummy hcd */
32 
33 static int vhci_hub_status(struct usb_hcd *hcd, char *buff);
34 static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
35 			    u16 wIndex, char *buff, u16 wLength);
36 static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
37 			    gfp_t mem_flags);
38 static int vhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status);
39 static int vhci_start(struct usb_hcd *vhci_hcd);
40 static void vhci_stop(struct usb_hcd *hcd);
41 static int vhci_get_frame_number(struct usb_hcd *hcd);
42 
43 static const char driver_name[] = "vhci_hcd";
44 static const char driver_desc[] = "USB/IP Virtual Host Controller";
45 
46 int vhci_num_controllers = VHCI_NR_HCS;
47 struct vhci *vhcis;
48 
49 static const char * const bit_desc[] = {
50 	"CONNECTION",		/*0*/
51 	"ENABLE",		/*1*/
52 	"SUSPEND",		/*2*/
53 	"OVER_CURRENT",		/*3*/
54 	"RESET",		/*4*/
55 	"L1",			/*5*/
56 	"R6",			/*6*/
57 	"R7",			/*7*/
58 	"POWER",		/*8*/
59 	"LOWSPEED",		/*9*/
60 	"HIGHSPEED",		/*10*/
61 	"PORT_TEST",		/*11*/
62 	"INDICATOR",		/*12*/
63 	"R13",			/*13*/
64 	"R14",			/*14*/
65 	"R15",			/*15*/
66 	"C_CONNECTION",		/*16*/
67 	"C_ENABLE",		/*17*/
68 	"C_SUSPEND",		/*18*/
69 	"C_OVER_CURRENT",	/*19*/
70 	"C_RESET",		/*20*/
71 	"C_L1",			/*21*/
72 	"R22",			/*22*/
73 	"R23",			/*23*/
74 	"R24",			/*24*/
75 	"R25",			/*25*/
76 	"R26",			/*26*/
77 	"R27",			/*27*/
78 	"R28",			/*28*/
79 	"R29",			/*29*/
80 	"R30",			/*30*/
81 	"R31",			/*31*/
82 };
83 
84 static const char * const bit_desc_ss[] = {
85 	"CONNECTION",		/*0*/
86 	"ENABLE",		/*1*/
87 	"SUSPEND",		/*2*/
88 	"OVER_CURRENT",		/*3*/
89 	"RESET",		/*4*/
90 	"L1",			/*5*/
91 	"R6",			/*6*/
92 	"R7",			/*7*/
93 	"R8",			/*8*/
94 	"POWER",		/*9*/
95 	"HIGHSPEED",		/*10*/
96 	"PORT_TEST",		/*11*/
97 	"INDICATOR",		/*12*/
98 	"R13",			/*13*/
99 	"R14",			/*14*/
100 	"R15",			/*15*/
101 	"C_CONNECTION",		/*16*/
102 	"C_ENABLE",		/*17*/
103 	"C_SUSPEND",		/*18*/
104 	"C_OVER_CURRENT",	/*19*/
105 	"C_RESET",		/*20*/
106 	"C_BH_RESET",		/*21*/
107 	"C_LINK_STATE",		/*22*/
108 	"C_CONFIG_ERROR",	/*23*/
109 	"R24",			/*24*/
110 	"R25",			/*25*/
111 	"R26",			/*26*/
112 	"R27",			/*27*/
113 	"R28",			/*28*/
114 	"R29",			/*29*/
115 	"R30",			/*30*/
116 	"R31",			/*31*/
117 };
118 
119 static void dump_port_status_diff(u32 prev_status, u32 new_status, bool usb3)
120 {
121 	int i = 0;
122 	u32 bit = 1;
123 	const char * const *desc = bit_desc;
124 
125 	if (usb3)
126 		desc = bit_desc_ss;
127 
128 	pr_debug("status prev -> new: %08x -> %08x\n", prev_status, new_status);
129 	while (bit) {
130 		u32 prev = prev_status & bit;
131 		u32 new = new_status & bit;
132 		char change;
133 
134 		if (!prev && new)
135 			change = '+';
136 		else if (prev && !new)
137 			change = '-';
138 		else
139 			change = ' ';
140 
141 		if (prev || new) {
142 			pr_debug(" %c%s\n", change, desc[i]);
143 
144 			if (bit == 1) /* USB_PORT_STAT_CONNECTION */
145 				pr_debug(" %c%s\n", change, "USB_PORT_STAT_SPEED_5GBPS");
146 		}
147 		bit <<= 1;
148 		i++;
149 	}
150 	pr_debug("\n");
151 }
152 
153 void rh_port_connect(struct vhci_device *vdev, enum usb_device_speed speed)
154 {
155 	struct vhci_hcd	*vhci_hcd = vdev_to_vhci_hcd(vdev);
156 	struct vhci *vhci = vhci_hcd->vhci;
157 	int		rhport = vdev->rhport;
158 	u32		status;
159 	unsigned long	flags;
160 
161 	usbip_dbg_vhci_rh("rh_port_connect %d\n", rhport);
162 
163 	spin_lock_irqsave(&vhci->lock, flags);
164 
165 	status = vhci_hcd->port_status[rhport];
166 
167 	status |= USB_PORT_STAT_CONNECTION | (1 << USB_PORT_FEAT_C_CONNECTION);
168 
169 	switch (speed) {
170 	case USB_SPEED_HIGH:
171 		status |= USB_PORT_STAT_HIGH_SPEED;
172 		break;
173 	case USB_SPEED_LOW:
174 		status |= USB_PORT_STAT_LOW_SPEED;
175 		break;
176 	default:
177 		break;
178 	}
179 
180 	vhci_hcd->port_status[rhport] = status;
181 
182 	spin_unlock_irqrestore(&vhci->lock, flags);
183 
184 	usb_hcd_poll_rh_status(vhci_hcd_to_hcd(vhci_hcd));
185 }
186 
187 static void rh_port_disconnect(struct vhci_device *vdev)
188 {
189 	struct vhci_hcd	*vhci_hcd = vdev_to_vhci_hcd(vdev);
190 	struct vhci *vhci = vhci_hcd->vhci;
191 	int		rhport = vdev->rhport;
192 	u32		status;
193 	unsigned long	flags;
194 
195 	usbip_dbg_vhci_rh("rh_port_disconnect %d\n", rhport);
196 
197 	spin_lock_irqsave(&vhci->lock, flags);
198 
199 	status = vhci_hcd->port_status[rhport];
200 
201 	status &= ~USB_PORT_STAT_CONNECTION;
202 	status |= (1 << USB_PORT_FEAT_C_CONNECTION);
203 
204 	vhci_hcd->port_status[rhport] = status;
205 
206 	spin_unlock_irqrestore(&vhci->lock, flags);
207 	usb_hcd_poll_rh_status(vhci_hcd_to_hcd(vhci_hcd));
208 }
209 
210 #define PORT_C_MASK				\
211 	((USB_PORT_STAT_C_CONNECTION		\
212 	  | USB_PORT_STAT_C_ENABLE		\
213 	  | USB_PORT_STAT_C_SUSPEND		\
214 	  | USB_PORT_STAT_C_OVERCURRENT		\
215 	  | USB_PORT_STAT_C_RESET) << 16)
216 
217 /*
218  * Returns 0 if the status hasn't changed, or the number of bytes in buf.
219  * Ports are 0-indexed from the HCD point of view,
220  * and 1-indexed from the USB core pointer of view.
221  *
222  * @buf: a bitmap to show which port status has been changed.
223  *  bit  0: reserved
224  *  bit  1: the status of port 0 has been changed.
225  *  bit  2: the status of port 1 has been changed.
226  *  ...
227  */
228 static int vhci_hub_status(struct usb_hcd *hcd, char *buf)
229 {
230 	struct vhci_hcd	*vhci_hcd = hcd_to_vhci_hcd(hcd);
231 	struct vhci *vhci = vhci_hcd->vhci;
232 	int		retval = DIV_ROUND_UP(VHCI_HC_PORTS + 1, 8);
233 	int		rhport;
234 	int		changed = 0;
235 	unsigned long	flags;
236 
237 	memset(buf, 0, retval);
238 
239 	spin_lock_irqsave(&vhci->lock, flags);
240 	if (!HCD_HW_ACCESSIBLE(hcd)) {
241 		usbip_dbg_vhci_rh("hw accessible flag not on?\n");
242 		goto done;
243 	}
244 
245 	/* check pseudo status register for each port */
246 	for (rhport = 0; rhport < VHCI_HC_PORTS; rhport++) {
247 		if ((vhci_hcd->port_status[rhport] & PORT_C_MASK)) {
248 			/* The status of a port has been changed, */
249 			usbip_dbg_vhci_rh("port %d status changed\n", rhport);
250 
251 			buf[(rhport + 1) / 8] |= 1 << (rhport + 1) % 8;
252 			changed = 1;
253 		}
254 	}
255 
256 	if ((hcd->state == HC_STATE_SUSPENDED) && (changed == 1))
257 		usb_hcd_resume_root_hub(hcd);
258 
259 done:
260 	spin_unlock_irqrestore(&vhci->lock, flags);
261 	return changed ? retval : 0;
262 }
263 
264 /* usb 3.0 root hub device descriptor */
265 static struct {
266 	struct usb_bos_descriptor bos;
267 	struct usb_ss_cap_descriptor ss_cap;
268 } __packed usb3_bos_desc = {
269 
270 	.bos = {
271 		.bLength		= USB_DT_BOS_SIZE,
272 		.bDescriptorType	= USB_DT_BOS,
273 		.wTotalLength		= cpu_to_le16(sizeof(usb3_bos_desc)),
274 		.bNumDeviceCaps		= 1,
275 	},
276 	.ss_cap = {
277 		.bLength		= USB_DT_USB_SS_CAP_SIZE,
278 		.bDescriptorType	= USB_DT_DEVICE_CAPABILITY,
279 		.bDevCapabilityType	= USB_SS_CAP_TYPE,
280 		.wSpeedSupported	= cpu_to_le16(USB_5GBPS_OPERATION),
281 		.bFunctionalitySupport	= ilog2(USB_5GBPS_OPERATION),
282 	},
283 };
284 
285 static inline void
286 ss_hub_descriptor(struct usb_hub_descriptor *desc)
287 {
288 	memset(desc, 0, sizeof *desc);
289 	desc->bDescriptorType = USB_DT_SS_HUB;
290 	desc->bDescLength = 12;
291 	desc->wHubCharacteristics = cpu_to_le16(
292 		HUB_CHAR_INDV_PORT_LPSM | HUB_CHAR_COMMON_OCPM);
293 	desc->bNbrPorts = VHCI_HC_PORTS;
294 	desc->u.ss.bHubHdrDecLat = 0x04; /* Worst case: 0.4 micro sec*/
295 	desc->u.ss.DeviceRemovable = 0xffff;
296 }
297 
298 static inline void hub_descriptor(struct usb_hub_descriptor *desc)
299 {
300 	int width;
301 
302 	memset(desc, 0, sizeof(*desc));
303 	desc->bDescriptorType = USB_DT_HUB;
304 	desc->wHubCharacteristics = cpu_to_le16(
305 		HUB_CHAR_INDV_PORT_LPSM | HUB_CHAR_COMMON_OCPM);
306 
307 	desc->bNbrPorts = VHCI_HC_PORTS;
308 	BUILD_BUG_ON(VHCI_HC_PORTS > USB_MAXCHILDREN);
309 	width = desc->bNbrPorts / 8 + 1;
310 	desc->bDescLength = USB_DT_HUB_NONVAR_SIZE + 2 * width;
311 	memset(&desc->u.hs.DeviceRemovable[0], 0, width);
312 	memset(&desc->u.hs.DeviceRemovable[width], 0xff, width);
313 }
314 
315 static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
316 			    u16 wIndex, char *buf, u16 wLength)
317 {
318 	struct vhci_hcd	*vhci_hcd;
319 	struct vhci	*vhci;
320 	int             retval = 0;
321 	int		rhport = -1;
322 	unsigned long	flags;
323 	bool invalid_rhport = false;
324 
325 	u32 prev_port_status[VHCI_HC_PORTS];
326 
327 	if (!HCD_HW_ACCESSIBLE(hcd))
328 		return -ETIMEDOUT;
329 
330 	/*
331 	 * NOTE:
332 	 * wIndex (bits 0-7) shows the port number and begins from 1?
333 	 */
334 	wIndex = ((__u8)(wIndex & 0x00ff));
335 	usbip_dbg_vhci_rh("typeReq %x wValue %x wIndex %x\n", typeReq, wValue,
336 			  wIndex);
337 
338 	/*
339 	 * wIndex can be 0 for some request types (typeReq). rhport is
340 	 * in valid range when wIndex >= 1 and < VHCI_HC_PORTS.
341 	 *
342 	 * Reference port_status[] only with valid rhport when
343 	 * invalid_rhport is false.
344 	 */
345 	if (wIndex < 1 || wIndex > VHCI_HC_PORTS) {
346 		invalid_rhport = true;
347 		if (wIndex > VHCI_HC_PORTS)
348 			pr_err("invalid port number %d\n", wIndex);
349 	} else
350 		rhport = wIndex - 1;
351 
352 	vhci_hcd = hcd_to_vhci_hcd(hcd);
353 	vhci = vhci_hcd->vhci;
354 
355 	spin_lock_irqsave(&vhci->lock, flags);
356 
357 	/* store old status and compare now and old later */
358 	if (usbip_dbg_flag_vhci_rh) {
359 		if (!invalid_rhport)
360 			memcpy(prev_port_status, vhci_hcd->port_status,
361 				sizeof(prev_port_status));
362 	}
363 
364 	switch (typeReq) {
365 	case ClearHubFeature:
366 		usbip_dbg_vhci_rh(" ClearHubFeature\n");
367 		break;
368 	case ClearPortFeature:
369 		if (invalid_rhport) {
370 			pr_err("invalid port number %d\n", wIndex);
371 			goto error;
372 		}
373 		switch (wValue) {
374 		case USB_PORT_FEAT_SUSPEND:
375 			if (hcd->speed == HCD_USB3) {
376 				pr_err(" ClearPortFeature: USB_PORT_FEAT_SUSPEND req not "
377 				       "supported for USB 3.0 roothub\n");
378 				goto error;
379 			}
380 			usbip_dbg_vhci_rh(
381 				" ClearPortFeature: USB_PORT_FEAT_SUSPEND\n");
382 			if (vhci_hcd->port_status[rhport] & USB_PORT_STAT_SUSPEND) {
383 				/* 20msec signaling */
384 				vhci_hcd->resuming = 1;
385 				vhci_hcd->re_timeout = jiffies + msecs_to_jiffies(20);
386 			}
387 			break;
388 		case USB_PORT_FEAT_POWER:
389 			usbip_dbg_vhci_rh(
390 				" ClearPortFeature: USB_PORT_FEAT_POWER\n");
391 			if (hcd->speed == HCD_USB3)
392 				vhci_hcd->port_status[rhport] &= ~USB_SS_PORT_STAT_POWER;
393 			else
394 				vhci_hcd->port_status[rhport] &= ~USB_PORT_STAT_POWER;
395 			break;
396 		default:
397 			usbip_dbg_vhci_rh(" ClearPortFeature: default %x\n",
398 					  wValue);
399 			if (wValue >= 32)
400 				goto error;
401 			vhci_hcd->port_status[rhport] &= ~(1 << wValue);
402 			break;
403 		}
404 		break;
405 	case GetHubDescriptor:
406 		usbip_dbg_vhci_rh(" GetHubDescriptor\n");
407 		if (hcd->speed == HCD_USB3 &&
408 				(wLength < USB_DT_SS_HUB_SIZE ||
409 				 wValue != (USB_DT_SS_HUB << 8))) {
410 			pr_err("Wrong hub descriptor type for USB 3.0 roothub.\n");
411 			goto error;
412 		}
413 		if (hcd->speed == HCD_USB3)
414 			ss_hub_descriptor((struct usb_hub_descriptor *) buf);
415 		else
416 			hub_descriptor((struct usb_hub_descriptor *) buf);
417 		break;
418 	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
419 		if (hcd->speed != HCD_USB3)
420 			goto error;
421 
422 		if ((wValue >> 8) != USB_DT_BOS)
423 			goto error;
424 
425 		memcpy(buf, &usb3_bos_desc, sizeof(usb3_bos_desc));
426 		retval = sizeof(usb3_bos_desc);
427 		break;
428 	case GetHubStatus:
429 		usbip_dbg_vhci_rh(" GetHubStatus\n");
430 		*(__le32 *) buf = cpu_to_le32(0);
431 		break;
432 	case GetPortStatus:
433 		usbip_dbg_vhci_rh(" GetPortStatus port %x\n", wIndex);
434 		if (invalid_rhport) {
435 			pr_err("invalid port number %d\n", wIndex);
436 			retval = -EPIPE;
437 			goto error;
438 		}
439 
440 		/* we do not care about resume. */
441 
442 		/* whoever resets or resumes must GetPortStatus to
443 		 * complete it!!
444 		 */
445 		if (vhci_hcd->resuming && time_after(jiffies, vhci_hcd->re_timeout)) {
446 			vhci_hcd->port_status[rhport] |= (1 << USB_PORT_FEAT_C_SUSPEND);
447 			vhci_hcd->port_status[rhport] &= ~(1 << USB_PORT_FEAT_SUSPEND);
448 			vhci_hcd->resuming = 0;
449 			vhci_hcd->re_timeout = 0;
450 		}
451 
452 		if ((vhci_hcd->port_status[rhport] & (1 << USB_PORT_FEAT_RESET)) !=
453 		    0 && time_after(jiffies, vhci_hcd->re_timeout)) {
454 			vhci_hcd->port_status[rhport] |= (1 << USB_PORT_FEAT_C_RESET);
455 			vhci_hcd->port_status[rhport] &= ~(1 << USB_PORT_FEAT_RESET);
456 			vhci_hcd->re_timeout = 0;
457 
458 			if (vhci_hcd->vdev[rhport].ud.status ==
459 			    VDEV_ST_NOTASSIGNED) {
460 				usbip_dbg_vhci_rh(
461 					" enable rhport %d (status %u)\n",
462 					rhport,
463 					vhci_hcd->vdev[rhport].ud.status);
464 				vhci_hcd->port_status[rhport] |=
465 					USB_PORT_STAT_ENABLE;
466 			}
467 
468 			if (hcd->speed < HCD_USB3) {
469 				switch (vhci_hcd->vdev[rhport].speed) {
470 				case USB_SPEED_HIGH:
471 					vhci_hcd->port_status[rhport] |=
472 					      USB_PORT_STAT_HIGH_SPEED;
473 					break;
474 				case USB_SPEED_LOW:
475 					vhci_hcd->port_status[rhport] |=
476 						USB_PORT_STAT_LOW_SPEED;
477 					break;
478 				default:
479 					pr_err("vhci_device speed not set\n");
480 					break;
481 				}
482 			}
483 		}
484 		((__le16 *) buf)[0] = cpu_to_le16(vhci_hcd->port_status[rhport]);
485 		((__le16 *) buf)[1] =
486 			cpu_to_le16(vhci_hcd->port_status[rhport] >> 16);
487 
488 		usbip_dbg_vhci_rh(" GetPortStatus bye %x %x\n", ((u16 *)buf)[0],
489 				  ((u16 *)buf)[1]);
490 		break;
491 	case SetHubFeature:
492 		usbip_dbg_vhci_rh(" SetHubFeature\n");
493 		retval = -EPIPE;
494 		break;
495 	case SetPortFeature:
496 		switch (wValue) {
497 		case USB_PORT_FEAT_LINK_STATE:
498 			usbip_dbg_vhci_rh(
499 				" SetPortFeature: USB_PORT_FEAT_LINK_STATE\n");
500 			if (hcd->speed != HCD_USB3) {
501 				pr_err("USB_PORT_FEAT_LINK_STATE req not "
502 				       "supported for USB 2.0 roothub\n");
503 				goto error;
504 			}
505 			/*
506 			 * Since this is dummy we don't have an actual link so
507 			 * there is nothing to do for the SET_LINK_STATE cmd
508 			 */
509 			break;
510 		case USB_PORT_FEAT_U1_TIMEOUT:
511 			usbip_dbg_vhci_rh(
512 				" SetPortFeature: USB_PORT_FEAT_U1_TIMEOUT\n");
513 			fallthrough;
514 		case USB_PORT_FEAT_U2_TIMEOUT:
515 			usbip_dbg_vhci_rh(
516 				" SetPortFeature: USB_PORT_FEAT_U2_TIMEOUT\n");
517 			/* TODO: add suspend/resume support! */
518 			if (hcd->speed != HCD_USB3) {
519 				pr_err("USB_PORT_FEAT_U1/2_TIMEOUT req not "
520 				       "supported for USB 2.0 roothub\n");
521 				goto error;
522 			}
523 			break;
524 		case USB_PORT_FEAT_SUSPEND:
525 			usbip_dbg_vhci_rh(
526 				" SetPortFeature: USB_PORT_FEAT_SUSPEND\n");
527 			/* Applicable only for USB2.0 hub */
528 			if (hcd->speed == HCD_USB3) {
529 				pr_err("USB_PORT_FEAT_SUSPEND req not "
530 				       "supported for USB 3.0 roothub\n");
531 				goto error;
532 			}
533 
534 			if (invalid_rhport) {
535 				pr_err("invalid port number %d\n", wIndex);
536 				goto error;
537 			}
538 
539 			vhci_hcd->port_status[rhport] |= USB_PORT_STAT_SUSPEND;
540 			break;
541 		case USB_PORT_FEAT_POWER:
542 			usbip_dbg_vhci_rh(
543 				" SetPortFeature: USB_PORT_FEAT_POWER\n");
544 			if (invalid_rhport) {
545 				pr_err("invalid port number %d\n", wIndex);
546 				goto error;
547 			}
548 			if (hcd->speed == HCD_USB3)
549 				vhci_hcd->port_status[rhport] |= USB_SS_PORT_STAT_POWER;
550 			else
551 				vhci_hcd->port_status[rhport] |= USB_PORT_STAT_POWER;
552 			break;
553 		case USB_PORT_FEAT_BH_PORT_RESET:
554 			usbip_dbg_vhci_rh(
555 				" SetPortFeature: USB_PORT_FEAT_BH_PORT_RESET\n");
556 			if (invalid_rhport) {
557 				pr_err("invalid port number %d\n", wIndex);
558 				goto error;
559 			}
560 			/* Applicable only for USB3.0 hub */
561 			if (hcd->speed != HCD_USB3) {
562 				pr_err("USB_PORT_FEAT_BH_PORT_RESET req not "
563 				       "supported for USB 2.0 roothub\n");
564 				goto error;
565 			}
566 			fallthrough;
567 		case USB_PORT_FEAT_RESET:
568 			usbip_dbg_vhci_rh(
569 				" SetPortFeature: USB_PORT_FEAT_RESET\n");
570 			if (invalid_rhport) {
571 				pr_err("invalid port number %d\n", wIndex);
572 				goto error;
573 			}
574 			/* if it's already enabled, disable */
575 			if (hcd->speed == HCD_USB3) {
576 				vhci_hcd->port_status[rhport] = 0;
577 				vhci_hcd->port_status[rhport] =
578 					(USB_SS_PORT_STAT_POWER |
579 					 USB_PORT_STAT_CONNECTION |
580 					 USB_PORT_STAT_RESET);
581 			} else if (vhci_hcd->port_status[rhport] & USB_PORT_STAT_ENABLE) {
582 				vhci_hcd->port_status[rhport] &= ~(USB_PORT_STAT_ENABLE
583 					| USB_PORT_STAT_LOW_SPEED
584 					| USB_PORT_STAT_HIGH_SPEED);
585 			}
586 
587 			/* 50msec reset signaling */
588 			vhci_hcd->re_timeout = jiffies + msecs_to_jiffies(50);
589 			fallthrough;
590 		default:
591 			usbip_dbg_vhci_rh(" SetPortFeature: default %d\n",
592 					  wValue);
593 			if (invalid_rhport) {
594 				pr_err("invalid port number %d\n", wIndex);
595 				goto error;
596 			}
597 			if (wValue >= 32)
598 				goto error;
599 			if (hcd->speed == HCD_USB3) {
600 				if ((vhci_hcd->port_status[rhport] &
601 				     USB_SS_PORT_STAT_POWER) != 0) {
602 					vhci_hcd->port_status[rhport] |= (1 << wValue);
603 				}
604 			} else
605 				if ((vhci_hcd->port_status[rhport] &
606 				     USB_PORT_STAT_POWER) != 0) {
607 					vhci_hcd->port_status[rhport] |= (1 << wValue);
608 				}
609 		}
610 		break;
611 	case GetPortErrorCount:
612 		usbip_dbg_vhci_rh(" GetPortErrorCount\n");
613 		if (hcd->speed != HCD_USB3) {
614 			pr_err("GetPortErrorCount req not "
615 			       "supported for USB 2.0 roothub\n");
616 			goto error;
617 		}
618 		/* We'll always return 0 since this is a dummy hub */
619 		*(__le32 *) buf = cpu_to_le32(0);
620 		break;
621 	case SetHubDepth:
622 		usbip_dbg_vhci_rh(" SetHubDepth\n");
623 		if (hcd->speed != HCD_USB3) {
624 			pr_err("SetHubDepth req not supported for "
625 			       "USB 2.0 roothub\n");
626 			goto error;
627 		}
628 		break;
629 	default:
630 		pr_err("default hub control req: %04x v%04x i%04x l%d\n",
631 			typeReq, wValue, wIndex, wLength);
632 error:
633 		/* "protocol stall" on error */
634 		retval = -EPIPE;
635 	}
636 
637 	if (usbip_dbg_flag_vhci_rh) {
638 		pr_debug("port %d\n", rhport);
639 		/* Only dump valid port status */
640 		if (!invalid_rhport) {
641 			dump_port_status_diff(prev_port_status[rhport],
642 					      vhci_hcd->port_status[rhport],
643 					      hcd->speed == HCD_USB3);
644 		}
645 	}
646 	usbip_dbg_vhci_rh(" bye\n");
647 
648 	spin_unlock_irqrestore(&vhci->lock, flags);
649 
650 	if (!invalid_rhport &&
651 	    (vhci_hcd->port_status[rhport] & PORT_C_MASK) != 0) {
652 		usb_hcd_poll_rh_status(hcd);
653 	}
654 
655 	return retval;
656 }
657 
658 static void vhci_tx_urb(struct urb *urb, struct vhci_device *vdev)
659 {
660 	struct vhci_priv *priv;
661 	struct vhci_hcd *vhci_hcd = vdev_to_vhci_hcd(vdev);
662 	unsigned long flags;
663 
664 	priv = kzalloc(sizeof(struct vhci_priv), GFP_ATOMIC);
665 	if (!priv) {
666 		usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_MALLOC);
667 		return;
668 	}
669 
670 	spin_lock_irqsave(&vdev->priv_lock, flags);
671 
672 	priv->seqnum = atomic_inc_return(&vhci_hcd->seqnum);
673 	if (priv->seqnum == 0xffff)
674 		dev_info(&urb->dev->dev, "seqnum max\n");
675 
676 	priv->vdev = vdev;
677 	priv->urb = urb;
678 
679 	urb->hcpriv = (void *) priv;
680 
681 	list_add_tail(&priv->list, &vdev->priv_tx);
682 
683 	wake_up(&vdev->waitq_tx);
684 	spin_unlock_irqrestore(&vdev->priv_lock, flags);
685 }
686 
687 static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flags)
688 {
689 	struct vhci_hcd *vhci_hcd = hcd_to_vhci_hcd(hcd);
690 	struct vhci *vhci = vhci_hcd->vhci;
691 	struct device *dev = &urb->dev->dev;
692 	u8 portnum = urb->dev->portnum;
693 	int ret = 0;
694 	struct vhci_device *vdev;
695 	unsigned long flags;
696 
697 	if (portnum > VHCI_HC_PORTS) {
698 		pr_err("invalid port number %d\n", portnum);
699 		return -ENODEV;
700 	}
701 	vdev = &vhci_hcd->vdev[portnum-1];
702 
703 	if (!urb->transfer_buffer && !urb->num_sgs &&
704 	     urb->transfer_buffer_length) {
705 		dev_dbg(dev, "Null URB transfer buffer\n");
706 		return -EINVAL;
707 	}
708 
709 	spin_lock_irqsave(&vhci->lock, flags);
710 
711 	if (urb->status != -EINPROGRESS) {
712 		dev_err(dev, "URB already unlinked!, status %d\n", urb->status);
713 		spin_unlock_irqrestore(&vhci->lock, flags);
714 		return urb->status;
715 	}
716 
717 	/* refuse enqueue for dead connection */
718 	spin_lock(&vdev->ud.lock);
719 	if (vdev->ud.status == VDEV_ST_NULL ||
720 	    vdev->ud.status == VDEV_ST_ERROR) {
721 		dev_err(dev, "enqueue for inactive port %d\n", vdev->rhport);
722 		spin_unlock(&vdev->ud.lock);
723 		spin_unlock_irqrestore(&vhci->lock, flags);
724 		return -ENODEV;
725 	}
726 	spin_unlock(&vdev->ud.lock);
727 
728 	ret = usb_hcd_link_urb_to_ep(hcd, urb);
729 	if (ret)
730 		goto no_need_unlink;
731 
732 	/*
733 	 * The enumeration process is as follows;
734 	 *
735 	 *  1. Get_Descriptor request to DevAddrs(0) EndPoint(0)
736 	 *     to get max packet length of default pipe
737 	 *
738 	 *  2. Set_Address request to DevAddr(0) EndPoint(0)
739 	 *
740 	 */
741 	if (usb_pipedevice(urb->pipe) == 0) {
742 		__u8 type = usb_pipetype(urb->pipe);
743 		struct usb_ctrlrequest *ctrlreq =
744 			(struct usb_ctrlrequest *) urb->setup_packet;
745 
746 		if (type != PIPE_CONTROL || !ctrlreq) {
747 			dev_err(dev, "invalid request to devnum 0\n");
748 			ret = -EINVAL;
749 			goto no_need_xmit;
750 		}
751 
752 		switch (ctrlreq->bRequest) {
753 		case USB_REQ_SET_ADDRESS:
754 			/* set_address may come when a device is reset */
755 			dev_info(dev, "SetAddress Request (%d) to port %d\n",
756 				 ctrlreq->wValue, vdev->rhport);
757 
758 			usb_put_dev(vdev->udev);
759 			vdev->udev = usb_get_dev(urb->dev);
760 
761 			spin_lock(&vdev->ud.lock);
762 			vdev->ud.status = VDEV_ST_USED;
763 			spin_unlock(&vdev->ud.lock);
764 
765 			if (urb->status == -EINPROGRESS) {
766 				/* This request is successfully completed. */
767 				/* If not -EINPROGRESS, possibly unlinked. */
768 				urb->status = 0;
769 			}
770 
771 			goto no_need_xmit;
772 
773 		case USB_REQ_GET_DESCRIPTOR:
774 			if (ctrlreq->wValue == cpu_to_le16(USB_DT_DEVICE << 8))
775 				usbip_dbg_vhci_hc(
776 					"Not yet?:Get_Descriptor to device 0 (get max pipe size)\n");
777 
778 			usb_put_dev(vdev->udev);
779 			vdev->udev = usb_get_dev(urb->dev);
780 			goto out;
781 
782 		default:
783 			/* NOT REACHED */
784 			dev_err(dev,
785 				"invalid request to devnum 0 bRequest %u, wValue %u\n",
786 				ctrlreq->bRequest,
787 				ctrlreq->wValue);
788 			ret =  -EINVAL;
789 			goto no_need_xmit;
790 		}
791 
792 	}
793 
794 out:
795 	vhci_tx_urb(urb, vdev);
796 	spin_unlock_irqrestore(&vhci->lock, flags);
797 
798 	return 0;
799 
800 no_need_xmit:
801 	usb_hcd_unlink_urb_from_ep(hcd, urb);
802 no_need_unlink:
803 	spin_unlock_irqrestore(&vhci->lock, flags);
804 	if (!ret) {
805 		/* usb_hcd_giveback_urb() should be called with
806 		 * irqs disabled
807 		 */
808 		local_irq_disable();
809 		usb_hcd_giveback_urb(hcd, urb, urb->status);
810 		local_irq_enable();
811 	}
812 	return ret;
813 }
814 
815 /*
816  * vhci_rx gives back the urb after receiving the reply of the urb.  If an
817  * unlink pdu is sent or not, vhci_rx receives a normal return pdu and gives
818  * back its urb. For the driver unlinking the urb, the content of the urb is
819  * not important, but the calling to its completion handler is important; the
820  * completion of unlinking is notified by the completion handler.
821  *
822  *
823  * CLIENT SIDE
824  *
825  * - When vhci_hcd receives RET_SUBMIT,
826  *
827  *	- case 1a). the urb of the pdu is not unlinking.
828  *		- normal case
829  *		=> just give back the urb
830  *
831  *	- case 1b). the urb of the pdu is unlinking.
832  *		- usbip.ko will return a reply of the unlinking request.
833  *		=> give back the urb now and go to case 2b).
834  *
835  * - When vhci_hcd receives RET_UNLINK,
836  *
837  *	- case 2a). a submit request is still pending in vhci_hcd.
838  *		- urb was really pending in usbip.ko and urb_unlink_urb() was
839  *		  completed there.
840  *		=> free a pending submit request
841  *		=> notify unlink completeness by giving back the urb
842  *
843  *	- case 2b). a submit request is *not* pending in vhci_hcd.
844  *		- urb was already given back to the core driver.
845  *		=> do not give back the urb
846  *
847  *
848  * SERVER SIDE
849  *
850  * - When usbip receives CMD_UNLINK,
851  *
852  *	- case 3a). the urb of the unlink request is now in submission.
853  *		=> do usb_unlink_urb().
854  *		=> after the unlink is completed, send RET_UNLINK.
855  *
856  *	- case 3b). the urb of the unlink request is not in submission.
857  *		- may be already completed or never be received
858  *		=> send RET_UNLINK
859  *
860  */
861 static int vhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
862 {
863 	struct vhci_hcd *vhci_hcd = hcd_to_vhci_hcd(hcd);
864 	struct vhci *vhci = vhci_hcd->vhci;
865 	struct vhci_priv *priv;
866 	struct vhci_device *vdev;
867 	unsigned long flags;
868 
869 	spin_lock_irqsave(&vhci->lock, flags);
870 
871 	priv = urb->hcpriv;
872 	if (!priv) {
873 		/* URB was never linked! or will be soon given back by
874 		 * vhci_rx. */
875 		spin_unlock_irqrestore(&vhci->lock, flags);
876 		return -EIDRM;
877 	}
878 
879 	{
880 		int ret = 0;
881 
882 		ret = usb_hcd_check_unlink_urb(hcd, urb, status);
883 		if (ret) {
884 			spin_unlock_irqrestore(&vhci->lock, flags);
885 			return ret;
886 		}
887 	}
888 
889 	 /* send unlink request here? */
890 	vdev = priv->vdev;
891 
892 	if (!vdev->ud.tcp_socket) {
893 		/* tcp connection is closed */
894 		spin_lock(&vdev->priv_lock);
895 
896 		list_del(&priv->list);
897 		kfree(priv);
898 		urb->hcpriv = NULL;
899 
900 		spin_unlock(&vdev->priv_lock);
901 
902 		/*
903 		 * If tcp connection is alive, we have sent CMD_UNLINK.
904 		 * vhci_rx will receive RET_UNLINK and give back the URB.
905 		 * Otherwise, we give back it here.
906 		 */
907 		usb_hcd_unlink_urb_from_ep(hcd, urb);
908 
909 		spin_unlock_irqrestore(&vhci->lock, flags);
910 		usb_hcd_giveback_urb(hcd, urb, urb->status);
911 		spin_lock_irqsave(&vhci->lock, flags);
912 
913 	} else {
914 		/* tcp connection is alive */
915 		struct vhci_unlink *unlink;
916 
917 		spin_lock(&vdev->priv_lock);
918 
919 		/* setup CMD_UNLINK pdu */
920 		unlink = kzalloc(sizeof(struct vhci_unlink), GFP_ATOMIC);
921 		if (!unlink) {
922 			spin_unlock(&vdev->priv_lock);
923 			spin_unlock_irqrestore(&vhci->lock, flags);
924 			usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_MALLOC);
925 			return -ENOMEM;
926 		}
927 
928 		unlink->seqnum = atomic_inc_return(&vhci_hcd->seqnum);
929 		if (unlink->seqnum == 0xffff)
930 			pr_info("seqnum max\n");
931 
932 		unlink->unlink_seqnum = priv->seqnum;
933 
934 		/* send cmd_unlink and try to cancel the pending URB in the
935 		 * peer */
936 		list_add_tail(&unlink->list, &vdev->unlink_tx);
937 		wake_up(&vdev->waitq_tx);
938 
939 		spin_unlock(&vdev->priv_lock);
940 	}
941 
942 	spin_unlock_irqrestore(&vhci->lock, flags);
943 
944 	usbip_dbg_vhci_hc("leave\n");
945 	return 0;
946 }
947 
948 static void vhci_device_unlink_cleanup(struct vhci_device *vdev)
949 {
950 	struct vhci_hcd *vhci_hcd = vdev_to_vhci_hcd(vdev);
951 	struct usb_hcd *hcd = vhci_hcd_to_hcd(vhci_hcd);
952 	struct vhci *vhci = vhci_hcd->vhci;
953 	struct vhci_unlink *unlink, *tmp;
954 	unsigned long flags;
955 
956 	spin_lock_irqsave(&vhci->lock, flags);
957 	spin_lock(&vdev->priv_lock);
958 
959 	list_for_each_entry_safe(unlink, tmp, &vdev->unlink_tx, list) {
960 		pr_info("unlink cleanup tx %lu\n", unlink->unlink_seqnum);
961 		list_del(&unlink->list);
962 		kfree(unlink);
963 	}
964 
965 	while (!list_empty(&vdev->unlink_rx)) {
966 		struct urb *urb;
967 
968 		unlink = list_first_entry(&vdev->unlink_rx, struct vhci_unlink,
969 			list);
970 
971 		/* give back URB of unanswered unlink request */
972 		pr_info("unlink cleanup rx %lu\n", unlink->unlink_seqnum);
973 
974 		urb = pickup_urb_and_free_priv(vdev, unlink->unlink_seqnum);
975 		if (!urb) {
976 			pr_info("the urb (seqnum %lu) was already given back\n",
977 				unlink->unlink_seqnum);
978 			list_del(&unlink->list);
979 			kfree(unlink);
980 			continue;
981 		}
982 
983 		urb->status = -ENODEV;
984 
985 		usb_hcd_unlink_urb_from_ep(hcd, urb);
986 
987 		list_del(&unlink->list);
988 
989 		spin_unlock(&vdev->priv_lock);
990 		spin_unlock_irqrestore(&vhci->lock, flags);
991 
992 		usb_hcd_giveback_urb(hcd, urb, urb->status);
993 
994 		spin_lock_irqsave(&vhci->lock, flags);
995 		spin_lock(&vdev->priv_lock);
996 
997 		kfree(unlink);
998 	}
999 
1000 	spin_unlock(&vdev->priv_lock);
1001 	spin_unlock_irqrestore(&vhci->lock, flags);
1002 }
1003 
1004 /*
1005  * The important thing is that only one context begins cleanup.
1006  * This is why error handling and cleanup become simple.
1007  * We do not want to consider race condition as possible.
1008  */
1009 static void vhci_shutdown_connection(struct usbip_device *ud)
1010 {
1011 	struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
1012 
1013 	/* need this? see stub_dev.c */
1014 	if (ud->tcp_socket) {
1015 		pr_debug("shutdown tcp_socket %d\n", ud->sockfd);
1016 		kernel_sock_shutdown(ud->tcp_socket, SHUT_RDWR);
1017 	}
1018 
1019 	/* kill threads related to this sdev */
1020 	if (vdev->ud.tcp_rx) {
1021 		kthread_stop_put(vdev->ud.tcp_rx);
1022 		vdev->ud.tcp_rx = NULL;
1023 	}
1024 	if (vdev->ud.tcp_tx) {
1025 		kthread_stop_put(vdev->ud.tcp_tx);
1026 		vdev->ud.tcp_tx = NULL;
1027 	}
1028 	pr_info("stop threads\n");
1029 
1030 	/* active connection is closed */
1031 	if (vdev->ud.tcp_socket) {
1032 		sockfd_put(vdev->ud.tcp_socket);
1033 		vdev->ud.tcp_socket = NULL;
1034 		vdev->ud.sockfd = -1;
1035 	}
1036 	pr_info("release socket\n");
1037 
1038 	vhci_device_unlink_cleanup(vdev);
1039 
1040 	/*
1041 	 * rh_port_disconnect() is a trigger of ...
1042 	 *   usb_disable_device():
1043 	 *	disable all the endpoints for a USB device.
1044 	 *   usb_disable_endpoint():
1045 	 *	disable endpoints. pending urbs are unlinked(dequeued).
1046 	 *
1047 	 * NOTE: After calling rh_port_disconnect(), the USB device drivers of a
1048 	 * detached device should release used urbs in a cleanup function (i.e.
1049 	 * xxx_disconnect()). Therefore, vhci_hcd does not need to release
1050 	 * pushed urbs and their private data in this function.
1051 	 *
1052 	 * NOTE: vhci_dequeue() must be considered carefully. When shutting down
1053 	 * a connection, vhci_shutdown_connection() expects vhci_dequeue()
1054 	 * gives back pushed urbs and frees their private data by request of
1055 	 * the cleanup function of a USB driver. When unlinking a urb with an
1056 	 * active connection, vhci_dequeue() does not give back the urb which
1057 	 * is actually given back by vhci_rx after receiving its return pdu.
1058 	 *
1059 	 */
1060 	rh_port_disconnect(vdev);
1061 
1062 	pr_info("disconnect device\n");
1063 }
1064 
1065 static void vhci_device_reset(struct usbip_device *ud)
1066 {
1067 	struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
1068 	unsigned long flags;
1069 
1070 	spin_lock_irqsave(&ud->lock, flags);
1071 
1072 	vdev->speed  = 0;
1073 	vdev->devid  = 0;
1074 
1075 	usb_put_dev(vdev->udev);
1076 	vdev->udev = NULL;
1077 
1078 	if (ud->tcp_socket) {
1079 		sockfd_put(ud->tcp_socket);
1080 		ud->tcp_socket = NULL;
1081 		ud->sockfd = -1;
1082 	}
1083 	ud->status = VDEV_ST_NULL;
1084 
1085 	spin_unlock_irqrestore(&ud->lock, flags);
1086 }
1087 
1088 static void vhci_device_unusable(struct usbip_device *ud)
1089 {
1090 	unsigned long flags;
1091 
1092 	spin_lock_irqsave(&ud->lock, flags);
1093 	ud->status = VDEV_ST_ERROR;
1094 	spin_unlock_irqrestore(&ud->lock, flags);
1095 }
1096 
1097 static void vhci_device_init(struct vhci_device *vdev)
1098 {
1099 	memset(vdev, 0, sizeof(struct vhci_device));
1100 
1101 	vdev->ud.side   = USBIP_VHCI;
1102 	vdev->ud.status = VDEV_ST_NULL;
1103 	spin_lock_init(&vdev->ud.lock);
1104 	mutex_init(&vdev->ud.sysfs_lock);
1105 
1106 	INIT_LIST_HEAD(&vdev->priv_rx);
1107 	INIT_LIST_HEAD(&vdev->priv_tx);
1108 	INIT_LIST_HEAD(&vdev->unlink_tx);
1109 	INIT_LIST_HEAD(&vdev->unlink_rx);
1110 	spin_lock_init(&vdev->priv_lock);
1111 
1112 	init_waitqueue_head(&vdev->waitq_tx);
1113 
1114 	vdev->ud.eh_ops.shutdown = vhci_shutdown_connection;
1115 	vdev->ud.eh_ops.reset = vhci_device_reset;
1116 	vdev->ud.eh_ops.unusable = vhci_device_unusable;
1117 
1118 	usbip_start_eh(&vdev->ud);
1119 }
1120 
1121 static int hcd_name_to_id(const char *name)
1122 {
1123 	char *c;
1124 	long val;
1125 	int ret;
1126 
1127 	c = strchr(name, '.');
1128 	if (c == NULL)
1129 		return 0;
1130 
1131 	ret = kstrtol(c+1, 10, &val);
1132 	if (ret < 0)
1133 		return ret;
1134 
1135 	return val;
1136 }
1137 
1138 static int vhci_setup(struct usb_hcd *hcd)
1139 {
1140 	struct vhci *vhci = *((void **)dev_get_platdata(hcd->self.controller));
1141 	if (usb_hcd_is_primary_hcd(hcd)) {
1142 		vhci->vhci_hcd_hs = hcd_to_vhci_hcd(hcd);
1143 		vhci->vhci_hcd_hs->vhci = vhci;
1144 		/*
1145 		 * Mark the first roothub as being USB 2.0.
1146 		 * The USB 3.0 roothub will be registered later by
1147 		 * vhci_hcd_probe()
1148 		 */
1149 		hcd->speed = HCD_USB2;
1150 		hcd->self.root_hub->speed = USB_SPEED_HIGH;
1151 	} else {
1152 		vhci->vhci_hcd_ss = hcd_to_vhci_hcd(hcd);
1153 		vhci->vhci_hcd_ss->vhci = vhci;
1154 		hcd->speed = HCD_USB3;
1155 		hcd->self.root_hub->speed = USB_SPEED_SUPER;
1156 	}
1157 
1158 	/*
1159 	 * Support SG.
1160 	 * sg_tablesize is an arbitrary value to alleviate memory pressure
1161 	 * on the host.
1162 	 */
1163 	hcd->self.sg_tablesize = 32;
1164 	hcd->self.no_sg_constraint = 1;
1165 
1166 	return 0;
1167 }
1168 
1169 static int vhci_start(struct usb_hcd *hcd)
1170 {
1171 	struct vhci_hcd *vhci_hcd = hcd_to_vhci_hcd(hcd);
1172 	int id, rhport;
1173 	int err;
1174 
1175 	usbip_dbg_vhci_hc("enter vhci_start\n");
1176 
1177 	if (usb_hcd_is_primary_hcd(hcd))
1178 		spin_lock_init(&vhci_hcd->vhci->lock);
1179 
1180 	/* initialize private data of usb_hcd */
1181 
1182 	for (rhport = 0; rhport < VHCI_HC_PORTS; rhport++) {
1183 		struct vhci_device *vdev = &vhci_hcd->vdev[rhport];
1184 
1185 		vhci_device_init(vdev);
1186 		vdev->rhport = rhport;
1187 	}
1188 
1189 	atomic_set(&vhci_hcd->seqnum, 0);
1190 
1191 	hcd->power_budget = 0; /* no limit */
1192 	hcd->uses_new_polling = 1;
1193 
1194 #ifdef CONFIG_USB_OTG
1195 	hcd->self.otg_port = 1;
1196 #endif
1197 
1198 	id = hcd_name_to_id(hcd_name(hcd));
1199 	if (id < 0) {
1200 		pr_err("invalid vhci name %s\n", hcd_name(hcd));
1201 		return -EINVAL;
1202 	}
1203 
1204 	/* vhci_hcd is now ready to be controlled through sysfs */
1205 	if (id == 0 && usb_hcd_is_primary_hcd(hcd)) {
1206 		err = vhci_init_attr_group();
1207 		if (err) {
1208 			dev_err(hcd_dev(hcd), "init attr group failed, err = %d\n", err);
1209 			return err;
1210 		}
1211 		err = sysfs_create_group(&hcd_dev(hcd)->kobj, &vhci_attr_group);
1212 		if (err) {
1213 			dev_err(hcd_dev(hcd), "create sysfs files failed, err = %d\n", err);
1214 			vhci_finish_attr_group();
1215 			return err;
1216 		}
1217 		pr_info("created sysfs %s\n", hcd_name(hcd));
1218 	}
1219 
1220 	return 0;
1221 }
1222 
1223 static void vhci_stop(struct usb_hcd *hcd)
1224 {
1225 	struct vhci_hcd *vhci_hcd = hcd_to_vhci_hcd(hcd);
1226 	int id, rhport;
1227 
1228 	usbip_dbg_vhci_hc("stop VHCI controller\n");
1229 
1230 	/* 1. remove the userland interface of vhci_hcd */
1231 	id = hcd_name_to_id(hcd_name(hcd));
1232 	if (id == 0 && usb_hcd_is_primary_hcd(hcd)) {
1233 		sysfs_remove_group(&hcd_dev(hcd)->kobj, &vhci_attr_group);
1234 		vhci_finish_attr_group();
1235 	}
1236 
1237 	/* 2. shutdown all the ports of vhci_hcd */
1238 	for (rhport = 0; rhport < VHCI_HC_PORTS; rhport++) {
1239 		struct vhci_device *vdev = &vhci_hcd->vdev[rhport];
1240 
1241 		usbip_event_add(&vdev->ud, VDEV_EVENT_REMOVED);
1242 		usbip_stop_eh(&vdev->ud);
1243 	}
1244 }
1245 
1246 static int vhci_get_frame_number(struct usb_hcd *hcd)
1247 {
1248 	dev_err_ratelimited(&hcd->self.root_hub->dev, "Not yet implemented\n");
1249 	return 0;
1250 }
1251 
1252 #ifdef CONFIG_PM
1253 
1254 /* FIXME: suspend/resume */
1255 static int vhci_bus_suspend(struct usb_hcd *hcd)
1256 {
1257 	struct vhci *vhci = *((void **)dev_get_platdata(hcd->self.controller));
1258 	unsigned long flags;
1259 
1260 	dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
1261 
1262 	spin_lock_irqsave(&vhci->lock, flags);
1263 	hcd->state = HC_STATE_SUSPENDED;
1264 	spin_unlock_irqrestore(&vhci->lock, flags);
1265 
1266 	return 0;
1267 }
1268 
1269 static int vhci_bus_resume(struct usb_hcd *hcd)
1270 {
1271 	struct vhci *vhci = *((void **)dev_get_platdata(hcd->self.controller));
1272 	int rc = 0;
1273 	unsigned long flags;
1274 
1275 	dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
1276 
1277 	spin_lock_irqsave(&vhci->lock, flags);
1278 	if (!HCD_HW_ACCESSIBLE(hcd))
1279 		rc = -ESHUTDOWN;
1280 	else
1281 		hcd->state = HC_STATE_RUNNING;
1282 	spin_unlock_irqrestore(&vhci->lock, flags);
1283 
1284 	return rc;
1285 }
1286 
1287 #else
1288 
1289 #define vhci_bus_suspend      NULL
1290 #define vhci_bus_resume       NULL
1291 #endif
1292 
1293 /* Change a group of bulk endpoints to support multiple stream IDs */
1294 static int vhci_alloc_streams(struct usb_hcd *hcd, struct usb_device *udev,
1295 	struct usb_host_endpoint **eps, unsigned int num_eps,
1296 	unsigned int num_streams, gfp_t mem_flags)
1297 {
1298 	dev_dbg(&hcd->self.root_hub->dev, "vhci_alloc_streams not implemented\n");
1299 	return 0;
1300 }
1301 
1302 /* Reverts a group of bulk endpoints back to not using stream IDs. */
1303 static int vhci_free_streams(struct usb_hcd *hcd, struct usb_device *udev,
1304 	struct usb_host_endpoint **eps, unsigned int num_eps,
1305 	gfp_t mem_flags)
1306 {
1307 	dev_dbg(&hcd->self.root_hub->dev, "vhci_free_streams not implemented\n");
1308 	return 0;
1309 }
1310 
1311 static const struct hc_driver vhci_hc_driver = {
1312 	.description	= driver_name,
1313 	.product_desc	= driver_desc,
1314 	.hcd_priv_size	= sizeof(struct vhci_hcd),
1315 
1316 	.flags		= HCD_USB3 | HCD_SHARED,
1317 
1318 	.reset		= vhci_setup,
1319 	.start		= vhci_start,
1320 	.stop		= vhci_stop,
1321 
1322 	.urb_enqueue	= vhci_urb_enqueue,
1323 	.urb_dequeue	= vhci_urb_dequeue,
1324 
1325 	.get_frame_number = vhci_get_frame_number,
1326 
1327 	.hub_status_data = vhci_hub_status,
1328 	.hub_control    = vhci_hub_control,
1329 	.bus_suspend	= vhci_bus_suspend,
1330 	.bus_resume	= vhci_bus_resume,
1331 
1332 	.alloc_streams	= vhci_alloc_streams,
1333 	.free_streams	= vhci_free_streams,
1334 };
1335 
1336 static int vhci_hcd_probe(struct platform_device *pdev)
1337 {
1338 	struct vhci             *vhci = *((void **)dev_get_platdata(&pdev->dev));
1339 	struct usb_hcd		*hcd_hs;
1340 	struct usb_hcd		*hcd_ss;
1341 	int			ret;
1342 
1343 	usbip_dbg_vhci_hc("name %s id %d\n", pdev->name, pdev->id);
1344 
1345 	/*
1346 	 * Allocate and initialize hcd.
1347 	 * Our private data is also allocated automatically.
1348 	 */
1349 	hcd_hs = usb_create_hcd(&vhci_hc_driver, &pdev->dev, dev_name(&pdev->dev));
1350 	if (!hcd_hs) {
1351 		pr_err("create primary hcd failed\n");
1352 		return -ENOMEM;
1353 	}
1354 	hcd_hs->has_tt = 1;
1355 
1356 	/*
1357 	 * Finish generic HCD structure initialization and register.
1358 	 * Call the driver's reset() and start() routines.
1359 	 */
1360 	ret = usb_add_hcd(hcd_hs, 0, 0);
1361 	if (ret != 0) {
1362 		pr_err("usb_add_hcd hs failed %d\n", ret);
1363 		goto put_usb2_hcd;
1364 	}
1365 
1366 	hcd_ss = usb_create_shared_hcd(&vhci_hc_driver, &pdev->dev,
1367 				       dev_name(&pdev->dev), hcd_hs);
1368 	if (!hcd_ss) {
1369 		ret = -ENOMEM;
1370 		pr_err("create shared hcd failed\n");
1371 		goto remove_usb2_hcd;
1372 	}
1373 
1374 	ret = usb_add_hcd(hcd_ss, 0, 0);
1375 	if (ret) {
1376 		pr_err("usb_add_hcd ss failed %d\n", ret);
1377 		goto put_usb3_hcd;
1378 	}
1379 
1380 	usbip_dbg_vhci_hc("bye\n");
1381 	return 0;
1382 
1383 put_usb3_hcd:
1384 	usb_put_hcd(hcd_ss);
1385 remove_usb2_hcd:
1386 	usb_remove_hcd(hcd_hs);
1387 put_usb2_hcd:
1388 	usb_put_hcd(hcd_hs);
1389 	vhci->vhci_hcd_hs = NULL;
1390 	vhci->vhci_hcd_ss = NULL;
1391 	return ret;
1392 }
1393 
1394 static int vhci_hcd_remove(struct platform_device *pdev)
1395 {
1396 	struct vhci *vhci = *((void **)dev_get_platdata(&pdev->dev));
1397 
1398 	/*
1399 	 * Disconnects the root hub,
1400 	 * then reverses the effects of usb_add_hcd(),
1401 	 * invoking the HCD's stop() methods.
1402 	 */
1403 	usb_remove_hcd(vhci_hcd_to_hcd(vhci->vhci_hcd_ss));
1404 	usb_put_hcd(vhci_hcd_to_hcd(vhci->vhci_hcd_ss));
1405 
1406 	usb_remove_hcd(vhci_hcd_to_hcd(vhci->vhci_hcd_hs));
1407 	usb_put_hcd(vhci_hcd_to_hcd(vhci->vhci_hcd_hs));
1408 
1409 	vhci->vhci_hcd_hs = NULL;
1410 	vhci->vhci_hcd_ss = NULL;
1411 
1412 	return 0;
1413 }
1414 
1415 #ifdef CONFIG_PM
1416 
1417 /* what should happen for USB/IP under suspend/resume? */
1418 static int vhci_hcd_suspend(struct platform_device *pdev, pm_message_t state)
1419 {
1420 	struct usb_hcd *hcd;
1421 	struct vhci *vhci;
1422 	int rhport;
1423 	int connected = 0;
1424 	int ret = 0;
1425 	unsigned long flags;
1426 
1427 	dev_dbg(&pdev->dev, "%s\n", __func__);
1428 
1429 	hcd = platform_get_drvdata(pdev);
1430 	if (!hcd)
1431 		return 0;
1432 
1433 	vhci = *((void **)dev_get_platdata(hcd->self.controller));
1434 
1435 	spin_lock_irqsave(&vhci->lock, flags);
1436 
1437 	for (rhport = 0; rhport < VHCI_HC_PORTS; rhport++) {
1438 		if (vhci->vhci_hcd_hs->port_status[rhport] &
1439 		    USB_PORT_STAT_CONNECTION)
1440 			connected += 1;
1441 
1442 		if (vhci->vhci_hcd_ss->port_status[rhport] &
1443 		    USB_PORT_STAT_CONNECTION)
1444 			connected += 1;
1445 	}
1446 
1447 	spin_unlock_irqrestore(&vhci->lock, flags);
1448 
1449 	if (connected > 0) {
1450 		dev_info(&pdev->dev,
1451 			 "We have %d active connection%s. Do not suspend.\n",
1452 			 connected, (connected == 1 ? "" : "s"));
1453 		ret =  -EBUSY;
1454 	} else {
1455 		dev_info(&pdev->dev, "suspend vhci_hcd");
1456 		clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
1457 	}
1458 
1459 	return ret;
1460 }
1461 
1462 static int vhci_hcd_resume(struct platform_device *pdev)
1463 {
1464 	struct usb_hcd *hcd;
1465 
1466 	dev_dbg(&pdev->dev, "%s\n", __func__);
1467 
1468 	hcd = platform_get_drvdata(pdev);
1469 	if (!hcd)
1470 		return 0;
1471 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
1472 	usb_hcd_poll_rh_status(hcd);
1473 
1474 	return 0;
1475 }
1476 
1477 #else
1478 
1479 #define vhci_hcd_suspend	NULL
1480 #define vhci_hcd_resume		NULL
1481 
1482 #endif
1483 
1484 static struct platform_driver vhci_driver = {
1485 	.probe	= vhci_hcd_probe,
1486 	.remove	= vhci_hcd_remove,
1487 	.suspend = vhci_hcd_suspend,
1488 	.resume	= vhci_hcd_resume,
1489 	.driver	= {
1490 		.name = driver_name,
1491 	},
1492 };
1493 
1494 static void del_platform_devices(void)
1495 {
1496 	struct platform_device *pdev;
1497 	int i;
1498 
1499 	for (i = 0; i < vhci_num_controllers; i++) {
1500 		pdev = vhcis[i].pdev;
1501 		if (pdev != NULL)
1502 			platform_device_unregister(pdev);
1503 		vhcis[i].pdev = NULL;
1504 	}
1505 	sysfs_remove_link(&platform_bus.kobj, driver_name);
1506 }
1507 
1508 static int __init vhci_hcd_init(void)
1509 {
1510 	int i, ret;
1511 
1512 	if (usb_disabled())
1513 		return -ENODEV;
1514 
1515 	if (vhci_num_controllers < 1)
1516 		vhci_num_controllers = 1;
1517 
1518 	vhcis = kcalloc(vhci_num_controllers, sizeof(struct vhci), GFP_KERNEL);
1519 	if (vhcis == NULL)
1520 		return -ENOMEM;
1521 
1522 	for (i = 0; i < vhci_num_controllers; i++) {
1523 		vhcis[i].pdev = platform_device_alloc(driver_name, i);
1524 		if (!vhcis[i].pdev) {
1525 			i--;
1526 			while (i >= 0)
1527 				platform_device_put(vhcis[i--].pdev);
1528 			ret = -ENOMEM;
1529 			goto err_device_alloc;
1530 		}
1531 	}
1532 	for (i = 0; i < vhci_num_controllers; i++) {
1533 		void *vhci = &vhcis[i];
1534 		ret = platform_device_add_data(vhcis[i].pdev, &vhci, sizeof(void *));
1535 		if (ret)
1536 			goto err_driver_register;
1537 	}
1538 
1539 	ret = platform_driver_register(&vhci_driver);
1540 	if (ret)
1541 		goto err_driver_register;
1542 
1543 	for (i = 0; i < vhci_num_controllers; i++) {
1544 		ret = platform_device_add(vhcis[i].pdev);
1545 		if (ret < 0) {
1546 			i--;
1547 			while (i >= 0)
1548 				platform_device_del(vhcis[i--].pdev);
1549 			goto err_add_hcd;
1550 		}
1551 	}
1552 
1553 	return ret;
1554 
1555 err_add_hcd:
1556 	platform_driver_unregister(&vhci_driver);
1557 err_driver_register:
1558 	for (i = 0; i < vhci_num_controllers; i++)
1559 		platform_device_put(vhcis[i].pdev);
1560 err_device_alloc:
1561 	kfree(vhcis);
1562 	return ret;
1563 }
1564 
1565 static void __exit vhci_hcd_exit(void)
1566 {
1567 	del_platform_devices();
1568 	platform_driver_unregister(&vhci_driver);
1569 	kfree(vhcis);
1570 }
1571 
1572 module_init(vhci_hcd_init);
1573 module_exit(vhci_hcd_exit);
1574 
1575 MODULE_AUTHOR(DRIVER_AUTHOR);
1576 MODULE_DESCRIPTION(DRIVER_DESC);
1577 MODULE_LICENSE("GPL");
1578