xref: /openbmc/linux/drivers/usb/usbip/vhci_hcd.c (revision 58f9d806)
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 			vhci_hcd->port_status[rhport] &= ~(1 << wValue);
400 			break;
401 		}
402 		break;
403 	case GetHubDescriptor:
404 		usbip_dbg_vhci_rh(" GetHubDescriptor\n");
405 		if (hcd->speed == HCD_USB3 &&
406 				(wLength < USB_DT_SS_HUB_SIZE ||
407 				 wValue != (USB_DT_SS_HUB << 8))) {
408 			pr_err("Wrong hub descriptor type for USB 3.0 roothub.\n");
409 			goto error;
410 		}
411 		if (hcd->speed == HCD_USB3)
412 			ss_hub_descriptor((struct usb_hub_descriptor *) buf);
413 		else
414 			hub_descriptor((struct usb_hub_descriptor *) buf);
415 		break;
416 	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
417 		if (hcd->speed != HCD_USB3)
418 			goto error;
419 
420 		if ((wValue >> 8) != USB_DT_BOS)
421 			goto error;
422 
423 		memcpy(buf, &usb3_bos_desc, sizeof(usb3_bos_desc));
424 		retval = sizeof(usb3_bos_desc);
425 		break;
426 	case GetHubStatus:
427 		usbip_dbg_vhci_rh(" GetHubStatus\n");
428 		*(__le32 *) buf = cpu_to_le32(0);
429 		break;
430 	case GetPortStatus:
431 		usbip_dbg_vhci_rh(" GetPortStatus port %x\n", wIndex);
432 		if (invalid_rhport) {
433 			pr_err("invalid port number %d\n", wIndex);
434 			retval = -EPIPE;
435 			goto error;
436 		}
437 
438 		/* we do not care about resume. */
439 
440 		/* whoever resets or resumes must GetPortStatus to
441 		 * complete it!!
442 		 */
443 		if (vhci_hcd->resuming && time_after(jiffies, vhci_hcd->re_timeout)) {
444 			vhci_hcd->port_status[rhport] |= (1 << USB_PORT_FEAT_C_SUSPEND);
445 			vhci_hcd->port_status[rhport] &= ~(1 << USB_PORT_FEAT_SUSPEND);
446 			vhci_hcd->resuming = 0;
447 			vhci_hcd->re_timeout = 0;
448 		}
449 
450 		if ((vhci_hcd->port_status[rhport] & (1 << USB_PORT_FEAT_RESET)) !=
451 		    0 && time_after(jiffies, vhci_hcd->re_timeout)) {
452 			vhci_hcd->port_status[rhport] |= (1 << USB_PORT_FEAT_C_RESET);
453 			vhci_hcd->port_status[rhport] &= ~(1 << USB_PORT_FEAT_RESET);
454 			vhci_hcd->re_timeout = 0;
455 
456 			if (vhci_hcd->vdev[rhport].ud.status ==
457 			    VDEV_ST_NOTASSIGNED) {
458 				usbip_dbg_vhci_rh(
459 					" enable rhport %d (status %u)\n",
460 					rhport,
461 					vhci_hcd->vdev[rhport].ud.status);
462 				vhci_hcd->port_status[rhport] |=
463 					USB_PORT_STAT_ENABLE;
464 			}
465 
466 			if (hcd->speed < HCD_USB3) {
467 				switch (vhci_hcd->vdev[rhport].speed) {
468 				case USB_SPEED_HIGH:
469 					vhci_hcd->port_status[rhport] |=
470 					      USB_PORT_STAT_HIGH_SPEED;
471 					break;
472 				case USB_SPEED_LOW:
473 					vhci_hcd->port_status[rhport] |=
474 						USB_PORT_STAT_LOW_SPEED;
475 					break;
476 				default:
477 					pr_err("vhci_device speed not set\n");
478 					break;
479 				}
480 			}
481 		}
482 		((__le16 *) buf)[0] = cpu_to_le16(vhci_hcd->port_status[rhport]);
483 		((__le16 *) buf)[1] =
484 			cpu_to_le16(vhci_hcd->port_status[rhport] >> 16);
485 
486 		usbip_dbg_vhci_rh(" GetPortStatus bye %x %x\n", ((u16 *)buf)[0],
487 				  ((u16 *)buf)[1]);
488 		break;
489 	case SetHubFeature:
490 		usbip_dbg_vhci_rh(" SetHubFeature\n");
491 		retval = -EPIPE;
492 		break;
493 	case SetPortFeature:
494 		switch (wValue) {
495 		case USB_PORT_FEAT_LINK_STATE:
496 			usbip_dbg_vhci_rh(
497 				" SetPortFeature: USB_PORT_FEAT_LINK_STATE\n");
498 			if (hcd->speed != HCD_USB3) {
499 				pr_err("USB_PORT_FEAT_LINK_STATE req not "
500 				       "supported for USB 2.0 roothub\n");
501 				goto error;
502 			}
503 			/*
504 			 * Since this is dummy we don't have an actual link so
505 			 * there is nothing to do for the SET_LINK_STATE cmd
506 			 */
507 			break;
508 		case USB_PORT_FEAT_U1_TIMEOUT:
509 			usbip_dbg_vhci_rh(
510 				" SetPortFeature: USB_PORT_FEAT_U1_TIMEOUT\n");
511 		case USB_PORT_FEAT_U2_TIMEOUT:
512 			usbip_dbg_vhci_rh(
513 				" SetPortFeature: USB_PORT_FEAT_U2_TIMEOUT\n");
514 			/* TODO: add suspend/resume support! */
515 			if (hcd->speed != HCD_USB3) {
516 				pr_err("USB_PORT_FEAT_U1/2_TIMEOUT req not "
517 				       "supported for USB 2.0 roothub\n");
518 				goto error;
519 			}
520 			break;
521 		case USB_PORT_FEAT_SUSPEND:
522 			usbip_dbg_vhci_rh(
523 				" SetPortFeature: USB_PORT_FEAT_SUSPEND\n");
524 			/* Applicable only for USB2.0 hub */
525 			if (hcd->speed == HCD_USB3) {
526 				pr_err("USB_PORT_FEAT_SUSPEND req not "
527 				       "supported for USB 3.0 roothub\n");
528 				goto error;
529 			}
530 
531 			if (invalid_rhport) {
532 				pr_err("invalid port number %d\n", wIndex);
533 				goto error;
534 			}
535 
536 			vhci_hcd->port_status[rhport] |= USB_PORT_STAT_SUSPEND;
537 			break;
538 		case USB_PORT_FEAT_POWER:
539 			usbip_dbg_vhci_rh(
540 				" SetPortFeature: USB_PORT_FEAT_POWER\n");
541 			if (invalid_rhport) {
542 				pr_err("invalid port number %d\n", wIndex);
543 				goto error;
544 			}
545 			if (hcd->speed == HCD_USB3)
546 				vhci_hcd->port_status[rhport] |= USB_SS_PORT_STAT_POWER;
547 			else
548 				vhci_hcd->port_status[rhport] |= USB_PORT_STAT_POWER;
549 			break;
550 		case USB_PORT_FEAT_BH_PORT_RESET:
551 			usbip_dbg_vhci_rh(
552 				" SetPortFeature: USB_PORT_FEAT_BH_PORT_RESET\n");
553 			if (invalid_rhport) {
554 				pr_err("invalid port number %d\n", wIndex);
555 				goto error;
556 			}
557 			/* Applicable only for USB3.0 hub */
558 			if (hcd->speed != HCD_USB3) {
559 				pr_err("USB_PORT_FEAT_BH_PORT_RESET req not "
560 				       "supported for USB 2.0 roothub\n");
561 				goto error;
562 			}
563 			/* FALLS THROUGH */
564 		case USB_PORT_FEAT_RESET:
565 			usbip_dbg_vhci_rh(
566 				" SetPortFeature: USB_PORT_FEAT_RESET\n");
567 			if (invalid_rhport) {
568 				pr_err("invalid port number %d\n", wIndex);
569 				goto error;
570 			}
571 			/* if it's already enabled, disable */
572 			if (hcd->speed == HCD_USB3) {
573 				vhci_hcd->port_status[rhport] = 0;
574 				vhci_hcd->port_status[rhport] =
575 					(USB_SS_PORT_STAT_POWER |
576 					 USB_PORT_STAT_CONNECTION |
577 					 USB_PORT_STAT_RESET);
578 			} else if (vhci_hcd->port_status[rhport] & USB_PORT_STAT_ENABLE) {
579 				vhci_hcd->port_status[rhport] &= ~(USB_PORT_STAT_ENABLE
580 					| USB_PORT_STAT_LOW_SPEED
581 					| USB_PORT_STAT_HIGH_SPEED);
582 			}
583 
584 			/* 50msec reset signaling */
585 			vhci_hcd->re_timeout = jiffies + msecs_to_jiffies(50);
586 
587 			/* FALLS THROUGH */
588 		default:
589 			usbip_dbg_vhci_rh(" SetPortFeature: default %d\n",
590 					  wValue);
591 			if (invalid_rhport) {
592 				pr_err("invalid port number %d\n", wIndex);
593 				goto error;
594 			}
595 			if (hcd->speed == HCD_USB3) {
596 				if ((vhci_hcd->port_status[rhport] &
597 				     USB_SS_PORT_STAT_POWER) != 0) {
598 					vhci_hcd->port_status[rhport] |= (1 << wValue);
599 				}
600 			} else
601 				if ((vhci_hcd->port_status[rhport] &
602 				     USB_PORT_STAT_POWER) != 0) {
603 					vhci_hcd->port_status[rhport] |= (1 << wValue);
604 				}
605 		}
606 		break;
607 	case GetPortErrorCount:
608 		usbip_dbg_vhci_rh(" GetPortErrorCount\n");
609 		if (hcd->speed != HCD_USB3) {
610 			pr_err("GetPortErrorCount req not "
611 			       "supported for USB 2.0 roothub\n");
612 			goto error;
613 		}
614 		/* We'll always return 0 since this is a dummy hub */
615 		*(__le32 *) buf = cpu_to_le32(0);
616 		break;
617 	case SetHubDepth:
618 		usbip_dbg_vhci_rh(" SetHubDepth\n");
619 		if (hcd->speed != HCD_USB3) {
620 			pr_err("SetHubDepth req not supported for "
621 			       "USB 2.0 roothub\n");
622 			goto error;
623 		}
624 		break;
625 	default:
626 		pr_err("default hub control req: %04x v%04x i%04x l%d\n",
627 			typeReq, wValue, wIndex, wLength);
628 error:
629 		/* "protocol stall" on error */
630 		retval = -EPIPE;
631 	}
632 
633 	if (usbip_dbg_flag_vhci_rh) {
634 		pr_debug("port %d\n", rhport);
635 		/* Only dump valid port status */
636 		if (!invalid_rhport) {
637 			dump_port_status_diff(prev_port_status[rhport],
638 					      vhci_hcd->port_status[rhport],
639 					      hcd->speed == HCD_USB3);
640 		}
641 	}
642 	usbip_dbg_vhci_rh(" bye\n");
643 
644 	spin_unlock_irqrestore(&vhci->lock, flags);
645 
646 	if (!invalid_rhport &&
647 	    (vhci_hcd->port_status[rhport] & PORT_C_MASK) != 0) {
648 		usb_hcd_poll_rh_status(hcd);
649 	}
650 
651 	return retval;
652 }
653 
654 static void vhci_tx_urb(struct urb *urb, struct vhci_device *vdev)
655 {
656 	struct vhci_priv *priv;
657 	struct vhci_hcd *vhci_hcd;
658 	unsigned long flags;
659 
660 	if (!vdev) {
661 		pr_err("could not get virtual device");
662 		return;
663 	}
664 	vhci_hcd = vdev_to_vhci_hcd(vdev);
665 
666 	priv = kzalloc(sizeof(struct vhci_priv), GFP_ATOMIC);
667 	if (!priv) {
668 		usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_MALLOC);
669 		return;
670 	}
671 
672 	spin_lock_irqsave(&vdev->priv_lock, flags);
673 
674 	priv->seqnum = atomic_inc_return(&vhci_hcd->seqnum);
675 	if (priv->seqnum == 0xffff)
676 		dev_info(&urb->dev->dev, "seqnum max\n");
677 
678 	priv->vdev = vdev;
679 	priv->urb = urb;
680 
681 	urb->hcpriv = (void *) priv;
682 
683 	list_add_tail(&priv->list, &vdev->priv_tx);
684 
685 	wake_up(&vdev->waitq_tx);
686 	spin_unlock_irqrestore(&vdev->priv_lock, flags);
687 }
688 
689 static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flags)
690 {
691 	struct vhci_hcd *vhci_hcd = hcd_to_vhci_hcd(hcd);
692 	struct vhci *vhci = vhci_hcd->vhci;
693 	struct device *dev = &urb->dev->dev;
694 	u8 portnum = urb->dev->portnum;
695 	int ret = 0;
696 	struct vhci_device *vdev;
697 	unsigned long flags;
698 
699 	if (portnum > VHCI_HC_PORTS) {
700 		pr_err("invalid port number %d\n", portnum);
701 		return -ENODEV;
702 	}
703 	vdev = &vhci_hcd->vdev[portnum-1];
704 
705 	/* patch to usb_sg_init() is in 2.5.60 */
706 	BUG_ON(!urb->transfer_buffer && urb->transfer_buffer_length);
707 
708 	spin_lock_irqsave(&vhci->lock, flags);
709 
710 	if (urb->status != -EINPROGRESS) {
711 		dev_err(dev, "URB already unlinked!, status %d\n", urb->status);
712 		spin_unlock_irqrestore(&vhci->lock, flags);
713 		return urb->status;
714 	}
715 
716 	/* refuse enqueue for dead connection */
717 	spin_lock(&vdev->ud.lock);
718 	if (vdev->ud.status == VDEV_ST_NULL ||
719 	    vdev->ud.status == VDEV_ST_ERROR) {
720 		dev_err(dev, "enqueue for inactive port %d\n", vdev->rhport);
721 		spin_unlock(&vdev->ud.lock);
722 		spin_unlock_irqrestore(&vhci->lock, flags);
723 		return -ENODEV;
724 	}
725 	spin_unlock(&vdev->ud.lock);
726 
727 	ret = usb_hcd_link_urb_to_ep(hcd, urb);
728 	if (ret)
729 		goto no_need_unlink;
730 
731 	/*
732 	 * The enumeration process is as follows;
733 	 *
734 	 *  1. Get_Descriptor request to DevAddrs(0) EndPoint(0)
735 	 *     to get max packet length of default pipe
736 	 *
737 	 *  2. Set_Address request to DevAddr(0) EndPoint(0)
738 	 *
739 	 */
740 	if (usb_pipedevice(urb->pipe) == 0) {
741 		__u8 type = usb_pipetype(urb->pipe);
742 		struct usb_ctrlrequest *ctrlreq =
743 			(struct usb_ctrlrequest *) urb->setup_packet;
744 
745 		if (type != PIPE_CONTROL || !ctrlreq) {
746 			dev_err(dev, "invalid request to devnum 0\n");
747 			ret = -EINVAL;
748 			goto no_need_xmit;
749 		}
750 
751 		switch (ctrlreq->bRequest) {
752 		case USB_REQ_SET_ADDRESS:
753 			/* set_address may come when a device is reset */
754 			dev_info(dev, "SetAddress Request (%d) to port %d\n",
755 				 ctrlreq->wValue, vdev->rhport);
756 
757 			usb_put_dev(vdev->udev);
758 			vdev->udev = usb_get_dev(urb->dev);
759 
760 			spin_lock(&vdev->ud.lock);
761 			vdev->ud.status = VDEV_ST_USED;
762 			spin_unlock(&vdev->ud.lock);
763 
764 			if (urb->status == -EINPROGRESS) {
765 				/* This request is successfully completed. */
766 				/* If not -EINPROGRESS, possibly unlinked. */
767 				urb->status = 0;
768 			}
769 
770 			goto no_need_xmit;
771 
772 		case USB_REQ_GET_DESCRIPTOR:
773 			if (ctrlreq->wValue == cpu_to_le16(USB_DT_DEVICE << 8))
774 				usbip_dbg_vhci_hc(
775 					"Not yet?:Get_Descriptor to device 0 (get max pipe size)\n");
776 
777 			usb_put_dev(vdev->udev);
778 			vdev->udev = usb_get_dev(urb->dev);
779 			goto out;
780 
781 		default:
782 			/* NOT REACHED */
783 			dev_err(dev,
784 				"invalid request to devnum 0 bRequest %u, wValue %u\n",
785 				ctrlreq->bRequest,
786 				ctrlreq->wValue);
787 			ret =  -EINVAL;
788 			goto no_need_xmit;
789 		}
790 
791 	}
792 
793 out:
794 	vhci_tx_urb(urb, vdev);
795 	spin_unlock_irqrestore(&vhci->lock, flags);
796 
797 	return 0;
798 
799 no_need_xmit:
800 	usb_hcd_unlink_urb_from_ep(hcd, urb);
801 no_need_unlink:
802 	spin_unlock_irqrestore(&vhci->lock, flags);
803 	if (!ret)
804 		usb_hcd_giveback_urb(hcd, urb, urb->status);
805 	return ret;
806 }
807 
808 /*
809  * vhci_rx gives back the urb after receiving the reply of the urb.  If an
810  * unlink pdu is sent or not, vhci_rx receives a normal return pdu and gives
811  * back its urb. For the driver unlinking the urb, the content of the urb is
812  * not important, but the calling to its completion handler is important; the
813  * completion of unlinking is notified by the completion handler.
814  *
815  *
816  * CLIENT SIDE
817  *
818  * - When vhci_hcd receives RET_SUBMIT,
819  *
820  *	- case 1a). the urb of the pdu is not unlinking.
821  *		- normal case
822  *		=> just give back the urb
823  *
824  *	- case 1b). the urb of the pdu is unlinking.
825  *		- usbip.ko will return a reply of the unlinking request.
826  *		=> give back the urb now and go to case 2b).
827  *
828  * - When vhci_hcd receives RET_UNLINK,
829  *
830  *	- case 2a). a submit request is still pending in vhci_hcd.
831  *		- urb was really pending in usbip.ko and urb_unlink_urb() was
832  *		  completed there.
833  *		=> free a pending submit request
834  *		=> notify unlink completeness by giving back the urb
835  *
836  *	- case 2b). a submit request is *not* pending in vhci_hcd.
837  *		- urb was already given back to the core driver.
838  *		=> do not give back the urb
839  *
840  *
841  * SERVER SIDE
842  *
843  * - When usbip receives CMD_UNLINK,
844  *
845  *	- case 3a). the urb of the unlink request is now in submission.
846  *		=> do usb_unlink_urb().
847  *		=> after the unlink is completed, send RET_UNLINK.
848  *
849  *	- case 3b). the urb of the unlink request is not in submission.
850  *		- may be already completed or never be received
851  *		=> send RET_UNLINK
852  *
853  */
854 static int vhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
855 {
856 	struct vhci_hcd *vhci_hcd = hcd_to_vhci_hcd(hcd);
857 	struct vhci *vhci = vhci_hcd->vhci;
858 	struct vhci_priv *priv;
859 	struct vhci_device *vdev;
860 	unsigned long flags;
861 
862 	spin_lock_irqsave(&vhci->lock, flags);
863 
864 	priv = urb->hcpriv;
865 	if (!priv) {
866 		/* URB was never linked! or will be soon given back by
867 		 * vhci_rx. */
868 		spin_unlock_irqrestore(&vhci->lock, flags);
869 		return -EIDRM;
870 	}
871 
872 	{
873 		int ret = 0;
874 
875 		ret = usb_hcd_check_unlink_urb(hcd, urb, status);
876 		if (ret) {
877 			spin_unlock_irqrestore(&vhci->lock, flags);
878 			return ret;
879 		}
880 	}
881 
882 	 /* send unlink request here? */
883 	vdev = priv->vdev;
884 
885 	if (!vdev->ud.tcp_socket) {
886 		/* tcp connection is closed */
887 		spin_lock(&vdev->priv_lock);
888 
889 		list_del(&priv->list);
890 		kfree(priv);
891 		urb->hcpriv = NULL;
892 
893 		spin_unlock(&vdev->priv_lock);
894 
895 		/*
896 		 * If tcp connection is alive, we have sent CMD_UNLINK.
897 		 * vhci_rx will receive RET_UNLINK and give back the URB.
898 		 * Otherwise, we give back it here.
899 		 */
900 		usb_hcd_unlink_urb_from_ep(hcd, urb);
901 
902 		spin_unlock_irqrestore(&vhci->lock, flags);
903 		usb_hcd_giveback_urb(hcd, urb, urb->status);
904 		spin_lock_irqsave(&vhci->lock, flags);
905 
906 	} else {
907 		/* tcp connection is alive */
908 		struct vhci_unlink *unlink;
909 
910 		spin_lock(&vdev->priv_lock);
911 
912 		/* setup CMD_UNLINK pdu */
913 		unlink = kzalloc(sizeof(struct vhci_unlink), GFP_ATOMIC);
914 		if (!unlink) {
915 			spin_unlock(&vdev->priv_lock);
916 			spin_unlock_irqrestore(&vhci->lock, flags);
917 			usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_MALLOC);
918 			return -ENOMEM;
919 		}
920 
921 		unlink->seqnum = atomic_inc_return(&vhci_hcd->seqnum);
922 		if (unlink->seqnum == 0xffff)
923 			pr_info("seqnum max\n");
924 
925 		unlink->unlink_seqnum = priv->seqnum;
926 
927 		/* send cmd_unlink and try to cancel the pending URB in the
928 		 * peer */
929 		list_add_tail(&unlink->list, &vdev->unlink_tx);
930 		wake_up(&vdev->waitq_tx);
931 
932 		spin_unlock(&vdev->priv_lock);
933 	}
934 
935 	spin_unlock_irqrestore(&vhci->lock, flags);
936 
937 	usbip_dbg_vhci_hc("leave\n");
938 	return 0;
939 }
940 
941 static void vhci_device_unlink_cleanup(struct vhci_device *vdev)
942 {
943 	struct vhci_hcd *vhci_hcd = vdev_to_vhci_hcd(vdev);
944 	struct usb_hcd *hcd = vhci_hcd_to_hcd(vhci_hcd);
945 	struct vhci *vhci = vhci_hcd->vhci;
946 	struct vhci_unlink *unlink, *tmp;
947 	unsigned long flags;
948 
949 	spin_lock_irqsave(&vhci->lock, flags);
950 	spin_lock(&vdev->priv_lock);
951 
952 	list_for_each_entry_safe(unlink, tmp, &vdev->unlink_tx, list) {
953 		pr_info("unlink cleanup tx %lu\n", unlink->unlink_seqnum);
954 		list_del(&unlink->list);
955 		kfree(unlink);
956 	}
957 
958 	while (!list_empty(&vdev->unlink_rx)) {
959 		struct urb *urb;
960 
961 		unlink = list_first_entry(&vdev->unlink_rx, struct vhci_unlink,
962 			list);
963 
964 		/* give back URB of unanswered unlink request */
965 		pr_info("unlink cleanup rx %lu\n", unlink->unlink_seqnum);
966 
967 		urb = pickup_urb_and_free_priv(vdev, unlink->unlink_seqnum);
968 		if (!urb) {
969 			pr_info("the urb (seqnum %lu) was already given back\n",
970 				unlink->unlink_seqnum);
971 			list_del(&unlink->list);
972 			kfree(unlink);
973 			continue;
974 		}
975 
976 		urb->status = -ENODEV;
977 
978 		usb_hcd_unlink_urb_from_ep(hcd, urb);
979 
980 		list_del(&unlink->list);
981 
982 		spin_unlock(&vdev->priv_lock);
983 		spin_unlock_irqrestore(&vhci->lock, flags);
984 
985 		usb_hcd_giveback_urb(hcd, urb, urb->status);
986 
987 		spin_lock_irqsave(&vhci->lock, flags);
988 		spin_lock(&vdev->priv_lock);
989 
990 		kfree(unlink);
991 	}
992 
993 	spin_unlock(&vdev->priv_lock);
994 	spin_unlock_irqrestore(&vhci->lock, flags);
995 }
996 
997 /*
998  * The important thing is that only one context begins cleanup.
999  * This is why error handling and cleanup become simple.
1000  * We do not want to consider race condition as possible.
1001  */
1002 static void vhci_shutdown_connection(struct usbip_device *ud)
1003 {
1004 	struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
1005 
1006 	/* need this? see stub_dev.c */
1007 	if (ud->tcp_socket) {
1008 		pr_debug("shutdown tcp_socket %d\n", ud->sockfd);
1009 		kernel_sock_shutdown(ud->tcp_socket, SHUT_RDWR);
1010 	}
1011 
1012 	/* kill threads related to this sdev */
1013 	if (vdev->ud.tcp_rx) {
1014 		kthread_stop_put(vdev->ud.tcp_rx);
1015 		vdev->ud.tcp_rx = NULL;
1016 	}
1017 	if (vdev->ud.tcp_tx) {
1018 		kthread_stop_put(vdev->ud.tcp_tx);
1019 		vdev->ud.tcp_tx = NULL;
1020 	}
1021 	pr_info("stop threads\n");
1022 
1023 	/* active connection is closed */
1024 	if (vdev->ud.tcp_socket) {
1025 		sockfd_put(vdev->ud.tcp_socket);
1026 		vdev->ud.tcp_socket = NULL;
1027 		vdev->ud.sockfd = -1;
1028 	}
1029 	pr_info("release socket\n");
1030 
1031 	vhci_device_unlink_cleanup(vdev);
1032 
1033 	/*
1034 	 * rh_port_disconnect() is a trigger of ...
1035 	 *   usb_disable_device():
1036 	 *	disable all the endpoints for a USB device.
1037 	 *   usb_disable_endpoint():
1038 	 *	disable endpoints. pending urbs are unlinked(dequeued).
1039 	 *
1040 	 * NOTE: After calling rh_port_disconnect(), the USB device drivers of a
1041 	 * detached device should release used urbs in a cleanup function (i.e.
1042 	 * xxx_disconnect()). Therefore, vhci_hcd does not need to release
1043 	 * pushed urbs and their private data in this function.
1044 	 *
1045 	 * NOTE: vhci_dequeue() must be considered carefully. When shutting down
1046 	 * a connection, vhci_shutdown_connection() expects vhci_dequeue()
1047 	 * gives back pushed urbs and frees their private data by request of
1048 	 * the cleanup function of a USB driver. When unlinking a urb with an
1049 	 * active connection, vhci_dequeue() does not give back the urb which
1050 	 * is actually given back by vhci_rx after receiving its return pdu.
1051 	 *
1052 	 */
1053 	rh_port_disconnect(vdev);
1054 
1055 	pr_info("disconnect device\n");
1056 }
1057 
1058 static void vhci_device_reset(struct usbip_device *ud)
1059 {
1060 	struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
1061 	unsigned long flags;
1062 
1063 	spin_lock_irqsave(&ud->lock, flags);
1064 
1065 	vdev->speed  = 0;
1066 	vdev->devid  = 0;
1067 
1068 	usb_put_dev(vdev->udev);
1069 	vdev->udev = NULL;
1070 
1071 	if (ud->tcp_socket) {
1072 		sockfd_put(ud->tcp_socket);
1073 		ud->tcp_socket = NULL;
1074 		ud->sockfd = -1;
1075 	}
1076 	ud->status = VDEV_ST_NULL;
1077 
1078 	spin_unlock_irqrestore(&ud->lock, flags);
1079 }
1080 
1081 static void vhci_device_unusable(struct usbip_device *ud)
1082 {
1083 	unsigned long flags;
1084 
1085 	spin_lock_irqsave(&ud->lock, flags);
1086 	ud->status = VDEV_ST_ERROR;
1087 	spin_unlock_irqrestore(&ud->lock, flags);
1088 }
1089 
1090 static void vhci_device_init(struct vhci_device *vdev)
1091 {
1092 	memset(vdev, 0, sizeof(struct vhci_device));
1093 
1094 	vdev->ud.side   = USBIP_VHCI;
1095 	vdev->ud.status = VDEV_ST_NULL;
1096 	spin_lock_init(&vdev->ud.lock);
1097 
1098 	INIT_LIST_HEAD(&vdev->priv_rx);
1099 	INIT_LIST_HEAD(&vdev->priv_tx);
1100 	INIT_LIST_HEAD(&vdev->unlink_tx);
1101 	INIT_LIST_HEAD(&vdev->unlink_rx);
1102 	spin_lock_init(&vdev->priv_lock);
1103 
1104 	init_waitqueue_head(&vdev->waitq_tx);
1105 
1106 	vdev->ud.eh_ops.shutdown = vhci_shutdown_connection;
1107 	vdev->ud.eh_ops.reset = vhci_device_reset;
1108 	vdev->ud.eh_ops.unusable = vhci_device_unusable;
1109 
1110 	usbip_start_eh(&vdev->ud);
1111 }
1112 
1113 static int hcd_name_to_id(const char *name)
1114 {
1115 	char *c;
1116 	long val;
1117 	int ret;
1118 
1119 	c = strchr(name, '.');
1120 	if (c == NULL)
1121 		return 0;
1122 
1123 	ret = kstrtol(c+1, 10, &val);
1124 	if (ret < 0)
1125 		return ret;
1126 
1127 	return val;
1128 }
1129 
1130 static int vhci_setup(struct usb_hcd *hcd)
1131 {
1132 	struct vhci *vhci = *((void **)dev_get_platdata(hcd->self.controller));
1133 	if (usb_hcd_is_primary_hcd(hcd)) {
1134 		vhci->vhci_hcd_hs = hcd_to_vhci_hcd(hcd);
1135 		vhci->vhci_hcd_hs->vhci = vhci;
1136 		/*
1137 		 * Mark the first roothub as being USB 2.0.
1138 		 * The USB 3.0 roothub will be registered later by
1139 		 * vhci_hcd_probe()
1140 		 */
1141 		hcd->speed = HCD_USB2;
1142 		hcd->self.root_hub->speed = USB_SPEED_HIGH;
1143 	} else {
1144 		vhci->vhci_hcd_ss = hcd_to_vhci_hcd(hcd);
1145 		vhci->vhci_hcd_ss->vhci = vhci;
1146 		hcd->speed = HCD_USB3;
1147 		hcd->self.root_hub->speed = USB_SPEED_SUPER;
1148 	}
1149 	return 0;
1150 }
1151 
1152 static int vhci_start(struct usb_hcd *hcd)
1153 {
1154 	struct vhci_hcd *vhci_hcd = hcd_to_vhci_hcd(hcd);
1155 	int id, rhport;
1156 	int err;
1157 
1158 	usbip_dbg_vhci_hc("enter vhci_start\n");
1159 
1160 	if (usb_hcd_is_primary_hcd(hcd))
1161 		spin_lock_init(&vhci_hcd->vhci->lock);
1162 
1163 	/* initialize private data of usb_hcd */
1164 
1165 	for (rhport = 0; rhport < VHCI_HC_PORTS; rhport++) {
1166 		struct vhci_device *vdev = &vhci_hcd->vdev[rhport];
1167 
1168 		vhci_device_init(vdev);
1169 		vdev->rhport = rhport;
1170 	}
1171 
1172 	atomic_set(&vhci_hcd->seqnum, 0);
1173 
1174 	hcd->power_budget = 0; /* no limit */
1175 	hcd->uses_new_polling = 1;
1176 
1177 #ifdef CONFIG_USB_OTG
1178 	hcd->self.otg_port = 1;
1179 #endif
1180 
1181 	id = hcd_name_to_id(hcd_name(hcd));
1182 	if (id < 0) {
1183 		pr_err("invalid vhci name %s\n", hcd_name(hcd));
1184 		return -EINVAL;
1185 	}
1186 
1187 	/* vhci_hcd is now ready to be controlled through sysfs */
1188 	if (id == 0 && usb_hcd_is_primary_hcd(hcd)) {
1189 		err = vhci_init_attr_group();
1190 		if (err) {
1191 			pr_err("init attr group\n");
1192 			return err;
1193 		}
1194 		err = sysfs_create_group(&hcd_dev(hcd)->kobj, &vhci_attr_group);
1195 		if (err) {
1196 			pr_err("create sysfs files\n");
1197 			vhci_finish_attr_group();
1198 			return err;
1199 		}
1200 		pr_info("created sysfs %s\n", hcd_name(hcd));
1201 	}
1202 
1203 	return 0;
1204 }
1205 
1206 static void vhci_stop(struct usb_hcd *hcd)
1207 {
1208 	struct vhci_hcd *vhci_hcd = hcd_to_vhci_hcd(hcd);
1209 	int id, rhport;
1210 
1211 	usbip_dbg_vhci_hc("stop VHCI controller\n");
1212 
1213 	/* 1. remove the userland interface of vhci_hcd */
1214 	id = hcd_name_to_id(hcd_name(hcd));
1215 	if (id == 0 && usb_hcd_is_primary_hcd(hcd)) {
1216 		sysfs_remove_group(&hcd_dev(hcd)->kobj, &vhci_attr_group);
1217 		vhci_finish_attr_group();
1218 	}
1219 
1220 	/* 2. shutdown all the ports of vhci_hcd */
1221 	for (rhport = 0; rhport < VHCI_HC_PORTS; rhport++) {
1222 		struct vhci_device *vdev = &vhci_hcd->vdev[rhport];
1223 
1224 		usbip_event_add(&vdev->ud, VDEV_EVENT_REMOVED);
1225 		usbip_stop_eh(&vdev->ud);
1226 	}
1227 }
1228 
1229 static int vhci_get_frame_number(struct usb_hcd *hcd)
1230 {
1231 	dev_err_ratelimited(&hcd->self.root_hub->dev, "Not yet implemented\n");
1232 	return 0;
1233 }
1234 
1235 #ifdef CONFIG_PM
1236 
1237 /* FIXME: suspend/resume */
1238 static int vhci_bus_suspend(struct usb_hcd *hcd)
1239 {
1240 	struct vhci *vhci = *((void **)dev_get_platdata(hcd->self.controller));
1241 	unsigned long flags;
1242 
1243 	dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
1244 
1245 	spin_lock_irqsave(&vhci->lock, flags);
1246 	hcd->state = HC_STATE_SUSPENDED;
1247 	spin_unlock_irqrestore(&vhci->lock, flags);
1248 
1249 	return 0;
1250 }
1251 
1252 static int vhci_bus_resume(struct usb_hcd *hcd)
1253 {
1254 	struct vhci *vhci = *((void **)dev_get_platdata(hcd->self.controller));
1255 	int rc = 0;
1256 	unsigned long flags;
1257 
1258 	dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
1259 
1260 	spin_lock_irqsave(&vhci->lock, flags);
1261 	if (!HCD_HW_ACCESSIBLE(hcd))
1262 		rc = -ESHUTDOWN;
1263 	else
1264 		hcd->state = HC_STATE_RUNNING;
1265 	spin_unlock_irqrestore(&vhci->lock, flags);
1266 
1267 	return rc;
1268 }
1269 
1270 #else
1271 
1272 #define vhci_bus_suspend      NULL
1273 #define vhci_bus_resume       NULL
1274 #endif
1275 
1276 /* Change a group of bulk endpoints to support multiple stream IDs */
1277 static int vhci_alloc_streams(struct usb_hcd *hcd, struct usb_device *udev,
1278 	struct usb_host_endpoint **eps, unsigned int num_eps,
1279 	unsigned int num_streams, gfp_t mem_flags)
1280 {
1281 	dev_dbg(&hcd->self.root_hub->dev, "vhci_alloc_streams not implemented\n");
1282 	return 0;
1283 }
1284 
1285 /* Reverts a group of bulk endpoints back to not using stream IDs. */
1286 static int vhci_free_streams(struct usb_hcd *hcd, struct usb_device *udev,
1287 	struct usb_host_endpoint **eps, unsigned int num_eps,
1288 	gfp_t mem_flags)
1289 {
1290 	dev_dbg(&hcd->self.root_hub->dev, "vhci_free_streams not implemented\n");
1291 	return 0;
1292 }
1293 
1294 static const struct hc_driver vhci_hc_driver = {
1295 	.description	= driver_name,
1296 	.product_desc	= driver_desc,
1297 	.hcd_priv_size	= sizeof(struct vhci_hcd),
1298 
1299 	.flags		= HCD_USB3 | HCD_SHARED,
1300 
1301 	.reset		= vhci_setup,
1302 	.start		= vhci_start,
1303 	.stop		= vhci_stop,
1304 
1305 	.urb_enqueue	= vhci_urb_enqueue,
1306 	.urb_dequeue	= vhci_urb_dequeue,
1307 
1308 	.get_frame_number = vhci_get_frame_number,
1309 
1310 	.hub_status_data = vhci_hub_status,
1311 	.hub_control    = vhci_hub_control,
1312 	.bus_suspend	= vhci_bus_suspend,
1313 	.bus_resume	= vhci_bus_resume,
1314 
1315 	.alloc_streams	= vhci_alloc_streams,
1316 	.free_streams	= vhci_free_streams,
1317 };
1318 
1319 static int vhci_hcd_probe(struct platform_device *pdev)
1320 {
1321 	struct vhci             *vhci = *((void **)dev_get_platdata(&pdev->dev));
1322 	struct usb_hcd		*hcd_hs;
1323 	struct usb_hcd		*hcd_ss;
1324 	int			ret;
1325 
1326 	usbip_dbg_vhci_hc("name %s id %d\n", pdev->name, pdev->id);
1327 
1328 	/*
1329 	 * Allocate and initialize hcd.
1330 	 * Our private data is also allocated automatically.
1331 	 */
1332 	hcd_hs = usb_create_hcd(&vhci_hc_driver, &pdev->dev, dev_name(&pdev->dev));
1333 	if (!hcd_hs) {
1334 		pr_err("create primary hcd failed\n");
1335 		return -ENOMEM;
1336 	}
1337 	hcd_hs->has_tt = 1;
1338 
1339 	/*
1340 	 * Finish generic HCD structure initialization and register.
1341 	 * Call the driver's reset() and start() routines.
1342 	 */
1343 	ret = usb_add_hcd(hcd_hs, 0, 0);
1344 	if (ret != 0) {
1345 		pr_err("usb_add_hcd hs failed %d\n", ret);
1346 		goto put_usb2_hcd;
1347 	}
1348 
1349 	hcd_ss = usb_create_shared_hcd(&vhci_hc_driver, &pdev->dev,
1350 				       dev_name(&pdev->dev), hcd_hs);
1351 	if (!hcd_ss) {
1352 		ret = -ENOMEM;
1353 		pr_err("create shared hcd failed\n");
1354 		goto remove_usb2_hcd;
1355 	}
1356 
1357 	ret = usb_add_hcd(hcd_ss, 0, 0);
1358 	if (ret) {
1359 		pr_err("usb_add_hcd ss failed %d\n", ret);
1360 		goto put_usb3_hcd;
1361 	}
1362 
1363 	usbip_dbg_vhci_hc("bye\n");
1364 	return 0;
1365 
1366 put_usb3_hcd:
1367 	usb_put_hcd(hcd_ss);
1368 remove_usb2_hcd:
1369 	usb_remove_hcd(hcd_hs);
1370 put_usb2_hcd:
1371 	usb_put_hcd(hcd_hs);
1372 	vhci->vhci_hcd_hs = NULL;
1373 	vhci->vhci_hcd_ss = NULL;
1374 	return ret;
1375 }
1376 
1377 static int vhci_hcd_remove(struct platform_device *pdev)
1378 {
1379 	struct vhci *vhci = *((void **)dev_get_platdata(&pdev->dev));
1380 
1381 	/*
1382 	 * Disconnects the root hub,
1383 	 * then reverses the effects of usb_add_hcd(),
1384 	 * invoking the HCD's stop() methods.
1385 	 */
1386 	usb_remove_hcd(vhci_hcd_to_hcd(vhci->vhci_hcd_ss));
1387 	usb_put_hcd(vhci_hcd_to_hcd(vhci->vhci_hcd_ss));
1388 
1389 	usb_remove_hcd(vhci_hcd_to_hcd(vhci->vhci_hcd_hs));
1390 	usb_put_hcd(vhci_hcd_to_hcd(vhci->vhci_hcd_hs));
1391 
1392 	vhci->vhci_hcd_hs = NULL;
1393 	vhci->vhci_hcd_ss = NULL;
1394 
1395 	return 0;
1396 }
1397 
1398 #ifdef CONFIG_PM
1399 
1400 /* what should happen for USB/IP under suspend/resume? */
1401 static int vhci_hcd_suspend(struct platform_device *pdev, pm_message_t state)
1402 {
1403 	struct usb_hcd *hcd;
1404 	struct vhci *vhci;
1405 	int rhport;
1406 	int connected = 0;
1407 	int ret = 0;
1408 	unsigned long flags;
1409 
1410 	dev_dbg(&pdev->dev, "%s\n", __func__);
1411 
1412 	hcd = platform_get_drvdata(pdev);
1413 	if (!hcd)
1414 		return 0;
1415 
1416 	vhci = *((void **)dev_get_platdata(hcd->self.controller));
1417 
1418 	spin_lock_irqsave(&vhci->lock, flags);
1419 
1420 	for (rhport = 0; rhport < VHCI_HC_PORTS; rhport++) {
1421 		if (vhci->vhci_hcd_hs->port_status[rhport] &
1422 		    USB_PORT_STAT_CONNECTION)
1423 			connected += 1;
1424 
1425 		if (vhci->vhci_hcd_ss->port_status[rhport] &
1426 		    USB_PORT_STAT_CONNECTION)
1427 			connected += 1;
1428 	}
1429 
1430 	spin_unlock_irqrestore(&vhci->lock, flags);
1431 
1432 	if (connected > 0) {
1433 		dev_info(&pdev->dev,
1434 			 "We have %d active connection%s. Do not suspend.\n",
1435 			 connected, (connected == 1 ? "" : "s"));
1436 		ret =  -EBUSY;
1437 	} else {
1438 		dev_info(&pdev->dev, "suspend vhci_hcd");
1439 		clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
1440 	}
1441 
1442 	return ret;
1443 }
1444 
1445 static int vhci_hcd_resume(struct platform_device *pdev)
1446 {
1447 	struct usb_hcd *hcd;
1448 
1449 	dev_dbg(&pdev->dev, "%s\n", __func__);
1450 
1451 	hcd = platform_get_drvdata(pdev);
1452 	if (!hcd)
1453 		return 0;
1454 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
1455 	usb_hcd_poll_rh_status(hcd);
1456 
1457 	return 0;
1458 }
1459 
1460 #else
1461 
1462 #define vhci_hcd_suspend	NULL
1463 #define vhci_hcd_resume		NULL
1464 
1465 #endif
1466 
1467 static struct platform_driver vhci_driver = {
1468 	.probe	= vhci_hcd_probe,
1469 	.remove	= vhci_hcd_remove,
1470 	.suspend = vhci_hcd_suspend,
1471 	.resume	= vhci_hcd_resume,
1472 	.driver	= {
1473 		.name = driver_name,
1474 	},
1475 };
1476 
1477 static void del_platform_devices(void)
1478 {
1479 	struct platform_device *pdev;
1480 	int i;
1481 
1482 	for (i = 0; i < vhci_num_controllers; i++) {
1483 		pdev = vhcis[i].pdev;
1484 		if (pdev != NULL)
1485 			platform_device_unregister(pdev);
1486 		vhcis[i].pdev = NULL;
1487 	}
1488 	sysfs_remove_link(&platform_bus.kobj, driver_name);
1489 }
1490 
1491 static int __init vhci_hcd_init(void)
1492 {
1493 	int i, ret;
1494 
1495 	if (usb_disabled())
1496 		return -ENODEV;
1497 
1498 	if (vhci_num_controllers < 1)
1499 		vhci_num_controllers = 1;
1500 
1501 	vhcis = kcalloc(vhci_num_controllers, sizeof(struct vhci), GFP_KERNEL);
1502 	if (vhcis == NULL)
1503 		return -ENOMEM;
1504 
1505 	for (i = 0; i < vhci_num_controllers; i++) {
1506 		vhcis[i].pdev = platform_device_alloc(driver_name, i);
1507 		if (!vhcis[i].pdev) {
1508 			i--;
1509 			while (i >= 0)
1510 				platform_device_put(vhcis[i--].pdev);
1511 			ret = -ENOMEM;
1512 			goto err_device_alloc;
1513 		}
1514 	}
1515 	for (i = 0; i < vhci_num_controllers; i++) {
1516 		void *vhci = &vhcis[i];
1517 		ret = platform_device_add_data(vhcis[i].pdev, &vhci, sizeof(void *));
1518 		if (ret)
1519 			goto err_driver_register;
1520 	}
1521 
1522 	ret = platform_driver_register(&vhci_driver);
1523 	if (ret)
1524 		goto err_driver_register;
1525 
1526 	for (i = 0; i < vhci_num_controllers; i++) {
1527 		ret = platform_device_add(vhcis[i].pdev);
1528 		if (ret < 0) {
1529 			i--;
1530 			while (i >= 0)
1531 				platform_device_del(vhcis[i--].pdev);
1532 			goto err_add_hcd;
1533 		}
1534 	}
1535 
1536 	return ret;
1537 
1538 err_add_hcd:
1539 	platform_driver_unregister(&vhci_driver);
1540 err_driver_register:
1541 	for (i = 0; i < vhci_num_controllers; i++)
1542 		platform_device_put(vhcis[i].pdev);
1543 err_device_alloc:
1544 	kfree(vhcis);
1545 	return ret;
1546 }
1547 
1548 static void __exit vhci_hcd_exit(void)
1549 {
1550 	del_platform_devices();
1551 	platform_driver_unregister(&vhci_driver);
1552 	kfree(vhcis);
1553 }
1554 
1555 module_init(vhci_hcd_init);
1556 module_exit(vhci_hcd_exit);
1557 
1558 MODULE_AUTHOR(DRIVER_AUTHOR);
1559 MODULE_DESCRIPTION(DRIVER_DESC);
1560 MODULE_LICENSE("GPL");
1561