xref: /openbmc/linux/drivers/usb/host/xhci-hub.c (revision 4800cd83)
1 /*
2  * xHCI host controller driver
3  *
4  * Copyright (C) 2008 Intel Corp.
5  *
6  * Author: Sarah Sharp
7  * Some code borrowed from the Linux EHCI driver.
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
16  * for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software Foundation,
20  * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21  */
22 
23 #include <asm/unaligned.h>
24 
25 #include "xhci.h"
26 
27 #define	PORT_WAKE_BITS	(PORT_WKOC_E | PORT_WKDISC_E | PORT_WKCONN_E)
28 #define	PORT_RWC_BITS	(PORT_CSC | PORT_PEC | PORT_WRC | PORT_OCC | \
29 			 PORT_RC | PORT_PLC | PORT_PE)
30 
31 static void xhci_hub_descriptor(struct xhci_hcd *xhci,
32 		struct usb_hub_descriptor *desc)
33 {
34 	int ports;
35 	u16 temp;
36 
37 	ports = HCS_MAX_PORTS(xhci->hcs_params1);
38 
39 	/* USB 3.0 hubs have a different descriptor, but we fake this for now */
40 	desc->bDescriptorType = 0x29;
41 	desc->bPwrOn2PwrGood = 10;	/* xhci section 5.4.9 says 20ms max */
42 	desc->bHubContrCurrent = 0;
43 
44 	desc->bNbrPorts = ports;
45 	temp = 1 + (ports / 8);
46 	desc->bDescLength = 7 + 2 * temp;
47 
48 	/* Why does core/hcd.h define bitmap?  It's just confusing. */
49 	memset(&desc->DeviceRemovable[0], 0, temp);
50 	memset(&desc->DeviceRemovable[temp], 0xff, temp);
51 
52 	/* Ugh, these should be #defines, FIXME */
53 	/* Using table 11-13 in USB 2.0 spec. */
54 	temp = 0;
55 	/* Bits 1:0 - support port power switching, or power always on */
56 	if (HCC_PPC(xhci->hcc_params))
57 		temp |= 0x0001;
58 	else
59 		temp |= 0x0002;
60 	/* Bit  2 - root hubs are not part of a compound device */
61 	/* Bits 4:3 - individual port over current protection */
62 	temp |= 0x0008;
63 	/* Bits 6:5 - no TTs in root ports */
64 	/* Bit  7 - no port indicators */
65 	desc->wHubCharacteristics = (__force __u16) cpu_to_le16(temp);
66 }
67 
68 static unsigned int xhci_port_speed(unsigned int port_status)
69 {
70 	if (DEV_LOWSPEED(port_status))
71 		return USB_PORT_STAT_LOW_SPEED;
72 	if (DEV_HIGHSPEED(port_status))
73 		return USB_PORT_STAT_HIGH_SPEED;
74 	if (DEV_SUPERSPEED(port_status))
75 		return USB_PORT_STAT_SUPER_SPEED;
76 	/*
77 	 * FIXME: Yes, we should check for full speed, but the core uses that as
78 	 * a default in portspeed() in usb/core/hub.c (which is the only place
79 	 * USB_PORT_STAT_*_SPEED is used).
80 	 */
81 	return 0;
82 }
83 
84 /*
85  * These bits are Read Only (RO) and should be saved and written to the
86  * registers: 0, 3, 10:13, 30
87  * connect status, over-current status, port speed, and device removable.
88  * connect status and port speed are also sticky - meaning they're in
89  * the AUX well and they aren't changed by a hot, warm, or cold reset.
90  */
91 #define	XHCI_PORT_RO	((1<<0) | (1<<3) | (0xf<<10) | (1<<30))
92 /*
93  * These bits are RW; writing a 0 clears the bit, writing a 1 sets the bit:
94  * bits 5:8, 9, 14:15, 25:27
95  * link state, port power, port indicator state, "wake on" enable state
96  */
97 #define XHCI_PORT_RWS	((0xf<<5) | (1<<9) | (0x3<<14) | (0x7<<25))
98 /*
99  * These bits are RW; writing a 1 sets the bit, writing a 0 has no effect:
100  * bit 4 (port reset)
101  */
102 #define	XHCI_PORT_RW1S	((1<<4))
103 /*
104  * These bits are RW; writing a 1 clears the bit, writing a 0 has no effect:
105  * bits 1, 17, 18, 19, 20, 21, 22, 23
106  * port enable/disable, and
107  * change bits: connect, PED, warm port reset changed (reserved zero for USB 2.0 ports),
108  * over-current, reset, link state, and L1 change
109  */
110 #define XHCI_PORT_RW1CS	((1<<1) | (0x7f<<17))
111 /*
112  * Bit 16 is RW, and writing a '1' to it causes the link state control to be
113  * latched in
114  */
115 #define	XHCI_PORT_RW	((1<<16))
116 /*
117  * These bits are Reserved Zero (RsvdZ) and zero should be written to them:
118  * bits 2, 24, 28:31
119  */
120 #define	XHCI_PORT_RZ	((1<<2) | (1<<24) | (0xf<<28))
121 
122 /*
123  * Given a port state, this function returns a value that would result in the
124  * port being in the same state, if the value was written to the port status
125  * control register.
126  * Save Read Only (RO) bits and save read/write bits where
127  * writing a 0 clears the bit and writing a 1 sets the bit (RWS).
128  * For all other types (RW1S, RW1CS, RW, and RZ), writing a '0' has no effect.
129  */
130 u32 xhci_port_state_to_neutral(u32 state)
131 {
132 	/* Save read-only status and port state */
133 	return (state & XHCI_PORT_RO) | (state & XHCI_PORT_RWS);
134 }
135 
136 /*
137  * find slot id based on port number.
138  */
139 int xhci_find_slot_id_by_port(struct xhci_hcd *xhci, u16 port)
140 {
141 	int slot_id;
142 	int i;
143 
144 	slot_id = 0;
145 	for (i = 0; i < MAX_HC_SLOTS; i++) {
146 		if (!xhci->devs[i])
147 			continue;
148 		if (xhci->devs[i]->port == port) {
149 			slot_id = i;
150 			break;
151 		}
152 	}
153 
154 	return slot_id;
155 }
156 
157 /*
158  * Stop device
159  * It issues stop endpoint command for EP 0 to 30. And wait the last command
160  * to complete.
161  * suspend will set to 1, if suspend bit need to set in command.
162  */
163 static int xhci_stop_device(struct xhci_hcd *xhci, int slot_id, int suspend)
164 {
165 	struct xhci_virt_device *virt_dev;
166 	struct xhci_command *cmd;
167 	unsigned long flags;
168 	int timeleft;
169 	int ret;
170 	int i;
171 
172 	ret = 0;
173 	virt_dev = xhci->devs[slot_id];
174 	cmd = xhci_alloc_command(xhci, false, true, GFP_NOIO);
175 	if (!cmd) {
176 		xhci_dbg(xhci, "Couldn't allocate command structure.\n");
177 		return -ENOMEM;
178 	}
179 
180 	spin_lock_irqsave(&xhci->lock, flags);
181 	for (i = LAST_EP_INDEX; i > 0; i--) {
182 		if (virt_dev->eps[i].ring && virt_dev->eps[i].ring->dequeue)
183 			xhci_queue_stop_endpoint(xhci, slot_id, i, suspend);
184 	}
185 	cmd->command_trb = xhci->cmd_ring->enqueue;
186 	list_add_tail(&cmd->cmd_list, &virt_dev->cmd_list);
187 	xhci_queue_stop_endpoint(xhci, slot_id, 0, suspend);
188 	xhci_ring_cmd_db(xhci);
189 	spin_unlock_irqrestore(&xhci->lock, flags);
190 
191 	/* Wait for last stop endpoint command to finish */
192 	timeleft = wait_for_completion_interruptible_timeout(
193 			cmd->completion,
194 			USB_CTRL_SET_TIMEOUT);
195 	if (timeleft <= 0) {
196 		xhci_warn(xhci, "%s while waiting for stop endpoint command\n",
197 				timeleft == 0 ? "Timeout" : "Signal");
198 		spin_lock_irqsave(&xhci->lock, flags);
199 		/* The timeout might have raced with the event ring handler, so
200 		 * only delete from the list if the item isn't poisoned.
201 		 */
202 		if (cmd->cmd_list.next != LIST_POISON1)
203 			list_del(&cmd->cmd_list);
204 		spin_unlock_irqrestore(&xhci->lock, flags);
205 		ret = -ETIME;
206 		goto command_cleanup;
207 	}
208 
209 command_cleanup:
210 	xhci_free_command(xhci, cmd);
211 	return ret;
212 }
213 
214 /*
215  * Ring device, it rings the all doorbells unconditionally.
216  */
217 void xhci_ring_device(struct xhci_hcd *xhci, int slot_id)
218 {
219 	int i;
220 
221 	for (i = 0; i < LAST_EP_INDEX + 1; i++)
222 		if (xhci->devs[slot_id]->eps[i].ring &&
223 		    xhci->devs[slot_id]->eps[i].ring->dequeue)
224 			xhci_ring_ep_doorbell(xhci, slot_id, i, 0);
225 
226 	return;
227 }
228 
229 static void xhci_disable_port(struct xhci_hcd *xhci, u16 wIndex,
230 		u32 __iomem *addr, u32 port_status)
231 {
232 	/* Don't allow the USB core to disable SuperSpeed ports. */
233 	if (xhci->port_array[wIndex] == 0x03) {
234 		xhci_dbg(xhci, "Ignoring request to disable "
235 				"SuperSpeed port.\n");
236 		return;
237 	}
238 
239 	/* Write 1 to disable the port */
240 	xhci_writel(xhci, port_status | PORT_PE, addr);
241 	port_status = xhci_readl(xhci, addr);
242 	xhci_dbg(xhci, "disable port, actual port %d status  = 0x%x\n",
243 			wIndex, port_status);
244 }
245 
246 static void xhci_clear_port_change_bit(struct xhci_hcd *xhci, u16 wValue,
247 		u16 wIndex, u32 __iomem *addr, u32 port_status)
248 {
249 	char *port_change_bit;
250 	u32 status;
251 
252 	switch (wValue) {
253 	case USB_PORT_FEAT_C_RESET:
254 		status = PORT_RC;
255 		port_change_bit = "reset";
256 		break;
257 	case USB_PORT_FEAT_C_CONNECTION:
258 		status = PORT_CSC;
259 		port_change_bit = "connect";
260 		break;
261 	case USB_PORT_FEAT_C_OVER_CURRENT:
262 		status = PORT_OCC;
263 		port_change_bit = "over-current";
264 		break;
265 	case USB_PORT_FEAT_C_ENABLE:
266 		status = PORT_PEC;
267 		port_change_bit = "enable/disable";
268 		break;
269 	case USB_PORT_FEAT_C_SUSPEND:
270 		status = PORT_PLC;
271 		port_change_bit = "suspend/resume";
272 		break;
273 	default:
274 		/* Should never happen */
275 		return;
276 	}
277 	/* Change bits are all write 1 to clear */
278 	xhci_writel(xhci, port_status | status, addr);
279 	port_status = xhci_readl(xhci, addr);
280 	xhci_dbg(xhci, "clear port %s change, actual port %d status  = 0x%x\n",
281 			port_change_bit, wIndex, port_status);
282 }
283 
284 int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
285 		u16 wIndex, char *buf, u16 wLength)
286 {
287 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
288 	int ports;
289 	unsigned long flags;
290 	u32 temp, temp1, status;
291 	int retval = 0;
292 	u32 __iomem *addr;
293 	int slot_id;
294 
295 	ports = HCS_MAX_PORTS(xhci->hcs_params1);
296 
297 	spin_lock_irqsave(&xhci->lock, flags);
298 	switch (typeReq) {
299 	case GetHubStatus:
300 		/* No power source, over-current reported per port */
301 		memset(buf, 0, 4);
302 		break;
303 	case GetHubDescriptor:
304 		xhci_hub_descriptor(xhci, (struct usb_hub_descriptor *) buf);
305 		break;
306 	case GetPortStatus:
307 		if (!wIndex || wIndex > ports)
308 			goto error;
309 		wIndex--;
310 		status = 0;
311 		addr = &xhci->op_regs->port_status_base + NUM_PORT_REGS*(wIndex & 0xff);
312 		temp = xhci_readl(xhci, addr);
313 		xhci_dbg(xhci, "get port status, actual port %d status  = 0x%x\n", wIndex, temp);
314 
315 		/* wPortChange bits */
316 		if (temp & PORT_CSC)
317 			status |= USB_PORT_STAT_C_CONNECTION << 16;
318 		if (temp & PORT_PEC)
319 			status |= USB_PORT_STAT_C_ENABLE << 16;
320 		if ((temp & PORT_OCC))
321 			status |= USB_PORT_STAT_C_OVERCURRENT << 16;
322 		/*
323 		 * FIXME ignoring reset and USB 2.1/3.0 specific
324 		 * changes
325 		 */
326 		if ((temp & PORT_PLS_MASK) == XDEV_U3
327 			&& (temp & PORT_POWER))
328 			status |= 1 << USB_PORT_FEAT_SUSPEND;
329 		if ((temp & PORT_PLS_MASK) == XDEV_RESUME) {
330 			if ((temp & PORT_RESET) || !(temp & PORT_PE))
331 				goto error;
332 			if (!DEV_SUPERSPEED(temp) && time_after_eq(jiffies,
333 						xhci->resume_done[wIndex])) {
334 				xhci_dbg(xhci, "Resume USB2 port %d\n",
335 					wIndex + 1);
336 				xhci->resume_done[wIndex] = 0;
337 				temp1 = xhci_port_state_to_neutral(temp);
338 				temp1 &= ~PORT_PLS_MASK;
339 				temp1 |= PORT_LINK_STROBE | XDEV_U0;
340 				xhci_writel(xhci, temp1, addr);
341 
342 				xhci_dbg(xhci, "set port %d resume\n",
343 					wIndex + 1);
344 				slot_id = xhci_find_slot_id_by_port(xhci,
345 								 wIndex + 1);
346 				if (!slot_id) {
347 					xhci_dbg(xhci, "slot_id is zero\n");
348 					goto error;
349 				}
350 				xhci_ring_device(xhci, slot_id);
351 				xhci->port_c_suspend[wIndex >> 5] |=
352 						1 << (wIndex & 31);
353 				xhci->suspended_ports[wIndex >> 5] &=
354 						~(1 << (wIndex & 31));
355 			}
356 		}
357 		if ((temp & PORT_PLS_MASK) == XDEV_U0
358 			&& (temp & PORT_POWER)
359 			&& (xhci->suspended_ports[wIndex >> 5] &
360 			    (1 << (wIndex & 31)))) {
361 			xhci->suspended_ports[wIndex >> 5] &=
362 					~(1 << (wIndex & 31));
363 			xhci->port_c_suspend[wIndex >> 5] |=
364 					1 << (wIndex & 31);
365 		}
366 		if (temp & PORT_CONNECT) {
367 			status |= USB_PORT_STAT_CONNECTION;
368 			status |= xhci_port_speed(temp);
369 		}
370 		if (temp & PORT_PE)
371 			status |= USB_PORT_STAT_ENABLE;
372 		if (temp & PORT_OC)
373 			status |= USB_PORT_STAT_OVERCURRENT;
374 		if (temp & PORT_RESET)
375 			status |= USB_PORT_STAT_RESET;
376 		if (temp & PORT_POWER)
377 			status |= USB_PORT_STAT_POWER;
378 		if (xhci->port_c_suspend[wIndex >> 5] & (1 << (wIndex & 31)))
379 			status |= 1 << USB_PORT_FEAT_C_SUSPEND;
380 		xhci_dbg(xhci, "Get port status returned 0x%x\n", status);
381 		put_unaligned(cpu_to_le32(status), (__le32 *) buf);
382 		break;
383 	case SetPortFeature:
384 		wIndex &= 0xff;
385 		if (!wIndex || wIndex > ports)
386 			goto error;
387 		wIndex--;
388 		addr = &xhci->op_regs->port_status_base + NUM_PORT_REGS*(wIndex & 0xff);
389 		temp = xhci_readl(xhci, addr);
390 		temp = xhci_port_state_to_neutral(temp);
391 		switch (wValue) {
392 		case USB_PORT_FEAT_SUSPEND:
393 			temp = xhci_readl(xhci, addr);
394 			/* In spec software should not attempt to suspend
395 			 * a port unless the port reports that it is in the
396 			 * enabled (PED = ‘1’,PLS < ‘3’) state.
397 			 */
398 			if ((temp & PORT_PE) == 0 || (temp & PORT_RESET)
399 				|| (temp & PORT_PLS_MASK) >= XDEV_U3) {
400 				xhci_warn(xhci, "USB core suspending device "
401 					  "not in U0/U1/U2.\n");
402 				goto error;
403 			}
404 
405 			slot_id = xhci_find_slot_id_by_port(xhci, wIndex + 1);
406 			if (!slot_id) {
407 				xhci_warn(xhci, "slot_id is zero\n");
408 				goto error;
409 			}
410 			/* unlock to execute stop endpoint commands */
411 			spin_unlock_irqrestore(&xhci->lock, flags);
412 			xhci_stop_device(xhci, slot_id, 1);
413 			spin_lock_irqsave(&xhci->lock, flags);
414 
415 			temp = xhci_port_state_to_neutral(temp);
416 			temp &= ~PORT_PLS_MASK;
417 			temp |= PORT_LINK_STROBE | XDEV_U3;
418 			xhci_writel(xhci, temp, addr);
419 
420 			spin_unlock_irqrestore(&xhci->lock, flags);
421 			msleep(10); /* wait device to enter */
422 			spin_lock_irqsave(&xhci->lock, flags);
423 
424 			temp = xhci_readl(xhci, addr);
425 			xhci->suspended_ports[wIndex >> 5] |=
426 					1 << (wIndex & (31));
427 			break;
428 		case USB_PORT_FEAT_POWER:
429 			/*
430 			 * Turn on ports, even if there isn't per-port switching.
431 			 * HC will report connect events even before this is set.
432 			 * However, khubd will ignore the roothub events until
433 			 * the roothub is registered.
434 			 */
435 			xhci_writel(xhci, temp | PORT_POWER, addr);
436 
437 			temp = xhci_readl(xhci, addr);
438 			xhci_dbg(xhci, "set port power, actual port %d status  = 0x%x\n", wIndex, temp);
439 			break;
440 		case USB_PORT_FEAT_RESET:
441 			temp = (temp | PORT_RESET);
442 			xhci_writel(xhci, temp, addr);
443 
444 			temp = xhci_readl(xhci, addr);
445 			xhci_dbg(xhci, "set port reset, actual port %d status  = 0x%x\n", wIndex, temp);
446 			break;
447 		default:
448 			goto error;
449 		}
450 		temp = xhci_readl(xhci, addr); /* unblock any posted writes */
451 		break;
452 	case ClearPortFeature:
453 		if (!wIndex || wIndex > ports)
454 			goto error;
455 		wIndex--;
456 		addr = &xhci->op_regs->port_status_base +
457 			NUM_PORT_REGS*(wIndex & 0xff);
458 		temp = xhci_readl(xhci, addr);
459 		temp = xhci_port_state_to_neutral(temp);
460 		switch (wValue) {
461 		case USB_PORT_FEAT_SUSPEND:
462 			temp = xhci_readl(xhci, addr);
463 			xhci_dbg(xhci, "clear USB_PORT_FEAT_SUSPEND\n");
464 			xhci_dbg(xhci, "PORTSC %04x\n", temp);
465 			if (temp & PORT_RESET)
466 				goto error;
467 			if (temp & XDEV_U3) {
468 				if ((temp & PORT_PE) == 0)
469 					goto error;
470 				if (DEV_SUPERSPEED(temp)) {
471 					temp = xhci_port_state_to_neutral(temp);
472 					temp &= ~PORT_PLS_MASK;
473 					temp |= PORT_LINK_STROBE | XDEV_U0;
474 					xhci_writel(xhci, temp, addr);
475 					xhci_readl(xhci, addr);
476 				} else {
477 					temp = xhci_port_state_to_neutral(temp);
478 					temp &= ~PORT_PLS_MASK;
479 					temp |= PORT_LINK_STROBE | XDEV_RESUME;
480 					xhci_writel(xhci, temp, addr);
481 
482 					spin_unlock_irqrestore(&xhci->lock,
483 							       flags);
484 					msleep(20);
485 					spin_lock_irqsave(&xhci->lock, flags);
486 
487 					temp = xhci_readl(xhci, addr);
488 					temp = xhci_port_state_to_neutral(temp);
489 					temp &= ~PORT_PLS_MASK;
490 					temp |= PORT_LINK_STROBE | XDEV_U0;
491 					xhci_writel(xhci, temp, addr);
492 				}
493 				xhci->port_c_suspend[wIndex >> 5] |=
494 						1 << (wIndex & 31);
495 			}
496 
497 			slot_id = xhci_find_slot_id_by_port(xhci, wIndex + 1);
498 			if (!slot_id) {
499 				xhci_dbg(xhci, "slot_id is zero\n");
500 				goto error;
501 			}
502 			xhci_ring_device(xhci, slot_id);
503 			break;
504 		case USB_PORT_FEAT_C_SUSPEND:
505 			xhci->port_c_suspend[wIndex >> 5] &=
506 					~(1 << (wIndex & 31));
507 		case USB_PORT_FEAT_C_RESET:
508 		case USB_PORT_FEAT_C_CONNECTION:
509 		case USB_PORT_FEAT_C_OVER_CURRENT:
510 		case USB_PORT_FEAT_C_ENABLE:
511 			xhci_clear_port_change_bit(xhci, wValue, wIndex,
512 					addr, temp);
513 			break;
514 		case USB_PORT_FEAT_ENABLE:
515 			xhci_disable_port(xhci, wIndex, addr, temp);
516 			break;
517 		default:
518 			goto error;
519 		}
520 		break;
521 	default:
522 error:
523 		/* "stall" on error */
524 		retval = -EPIPE;
525 	}
526 	spin_unlock_irqrestore(&xhci->lock, flags);
527 	return retval;
528 }
529 
530 /*
531  * Returns 0 if the status hasn't changed, or the number of bytes in buf.
532  * Ports are 0-indexed from the HCD point of view,
533  * and 1-indexed from the USB core pointer of view.
534  *
535  * Note that the status change bits will be cleared as soon as a port status
536  * change event is generated, so we use the saved status from that event.
537  */
538 int xhci_hub_status_data(struct usb_hcd *hcd, char *buf)
539 {
540 	unsigned long flags;
541 	u32 temp, status;
542 	u32 mask;
543 	int i, retval;
544 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
545 	int ports;
546 	u32 __iomem *addr;
547 
548 	ports = HCS_MAX_PORTS(xhci->hcs_params1);
549 
550 	/* Initial status is no changes */
551 	retval = (ports + 8) / 8;
552 	memset(buf, 0, retval);
553 	status = 0;
554 
555 	mask = PORT_CSC | PORT_PEC | PORT_OCC;
556 
557 	spin_lock_irqsave(&xhci->lock, flags);
558 	/* For each port, did anything change?  If so, set that bit in buf. */
559 	for (i = 0; i < ports; i++) {
560 		addr = &xhci->op_regs->port_status_base +
561 			NUM_PORT_REGS*i;
562 		temp = xhci_readl(xhci, addr);
563 		if ((temp & mask) != 0 ||
564 			(xhci->port_c_suspend[i >> 5] &	1 << (i & 31)) ||
565 			(xhci->resume_done[i] && time_after_eq(
566 			    jiffies, xhci->resume_done[i]))) {
567 			buf[(i + 1) / 8] |= 1 << (i + 1) % 8;
568 			status = 1;
569 		}
570 	}
571 	spin_unlock_irqrestore(&xhci->lock, flags);
572 	return status ? retval : 0;
573 }
574 
575 #ifdef CONFIG_PM
576 
577 int xhci_bus_suspend(struct usb_hcd *hcd)
578 {
579 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
580 	int port;
581 	unsigned long flags;
582 
583 	xhci_dbg(xhci, "suspend root hub\n");
584 
585 	spin_lock_irqsave(&xhci->lock, flags);
586 
587 	if (hcd->self.root_hub->do_remote_wakeup) {
588 		port = HCS_MAX_PORTS(xhci->hcs_params1);
589 		while (port--) {
590 			if (xhci->resume_done[port] != 0) {
591 				spin_unlock_irqrestore(&xhci->lock, flags);
592 				xhci_dbg(xhci, "suspend failed because "
593 						"port %d is resuming\n",
594 						port + 1);
595 				return -EBUSY;
596 			}
597 		}
598 	}
599 
600 	port = HCS_MAX_PORTS(xhci->hcs_params1);
601 	xhci->bus_suspended = 0;
602 	while (port--) {
603 		/* suspend the port if the port is not suspended */
604 		u32 __iomem *addr;
605 		u32 t1, t2;
606 		int slot_id;
607 
608 		addr = &xhci->op_regs->port_status_base +
609 			NUM_PORT_REGS * (port & 0xff);
610 		t1 = xhci_readl(xhci, addr);
611 		t2 = xhci_port_state_to_neutral(t1);
612 
613 		if ((t1 & PORT_PE) && !(t1 & PORT_PLS_MASK)) {
614 			xhci_dbg(xhci, "port %d not suspended\n", port);
615 			slot_id = xhci_find_slot_id_by_port(xhci, port + 1);
616 			if (slot_id) {
617 				spin_unlock_irqrestore(&xhci->lock, flags);
618 				xhci_stop_device(xhci, slot_id, 1);
619 				spin_lock_irqsave(&xhci->lock, flags);
620 			}
621 			t2 &= ~PORT_PLS_MASK;
622 			t2 |= PORT_LINK_STROBE | XDEV_U3;
623 			set_bit(port, &xhci->bus_suspended);
624 		}
625 		if (hcd->self.root_hub->do_remote_wakeup) {
626 			if (t1 & PORT_CONNECT) {
627 				t2 |= PORT_WKOC_E | PORT_WKDISC_E;
628 				t2 &= ~PORT_WKCONN_E;
629 			} else {
630 				t2 |= PORT_WKOC_E | PORT_WKCONN_E;
631 				t2 &= ~PORT_WKDISC_E;
632 			}
633 		} else
634 			t2 &= ~PORT_WAKE_BITS;
635 
636 		t1 = xhci_port_state_to_neutral(t1);
637 		if (t1 != t2)
638 			xhci_writel(xhci, t2, addr);
639 
640 		if (DEV_HIGHSPEED(t1)) {
641 			/* enable remote wake up for USB 2.0 */
642 			u32 __iomem *addr;
643 			u32 tmp;
644 
645 			addr = &xhci->op_regs->port_power_base +
646 				NUM_PORT_REGS * (port & 0xff);
647 			tmp = xhci_readl(xhci, addr);
648 			tmp |= PORT_RWE;
649 			xhci_writel(xhci, tmp, addr);
650 		}
651 	}
652 	hcd->state = HC_STATE_SUSPENDED;
653 	xhci->next_statechange = jiffies + msecs_to_jiffies(10);
654 	spin_unlock_irqrestore(&xhci->lock, flags);
655 	return 0;
656 }
657 
658 int xhci_bus_resume(struct usb_hcd *hcd)
659 {
660 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
661 	int port;
662 	u32 temp;
663 	unsigned long flags;
664 
665 	xhci_dbg(xhci, "resume root hub\n");
666 
667 	if (time_before(jiffies, xhci->next_statechange))
668 		msleep(5);
669 
670 	spin_lock_irqsave(&xhci->lock, flags);
671 	if (!HCD_HW_ACCESSIBLE(hcd)) {
672 		spin_unlock_irqrestore(&xhci->lock, flags);
673 		return -ESHUTDOWN;
674 	}
675 
676 	/* delay the irqs */
677 	temp = xhci_readl(xhci, &xhci->op_regs->command);
678 	temp &= ~CMD_EIE;
679 	xhci_writel(xhci, temp, &xhci->op_regs->command);
680 
681 	port = HCS_MAX_PORTS(xhci->hcs_params1);
682 	while (port--) {
683 		/* Check whether need resume ports. If needed
684 		   resume port and disable remote wakeup */
685 		u32 __iomem *addr;
686 		u32 temp;
687 		int slot_id;
688 
689 		addr = &xhci->op_regs->port_status_base +
690 			NUM_PORT_REGS * (port & 0xff);
691 		temp = xhci_readl(xhci, addr);
692 		if (DEV_SUPERSPEED(temp))
693 			temp &= ~(PORT_RWC_BITS | PORT_CEC | PORT_WAKE_BITS);
694 		else
695 			temp &= ~(PORT_RWC_BITS | PORT_WAKE_BITS);
696 		if (test_bit(port, &xhci->bus_suspended) &&
697 		    (temp & PORT_PLS_MASK)) {
698 			if (DEV_SUPERSPEED(temp)) {
699 				temp = xhci_port_state_to_neutral(temp);
700 				temp &= ~PORT_PLS_MASK;
701 				temp |= PORT_LINK_STROBE | XDEV_U0;
702 				xhci_writel(xhci, temp, addr);
703 			} else {
704 				temp = xhci_port_state_to_neutral(temp);
705 				temp &= ~PORT_PLS_MASK;
706 				temp |= PORT_LINK_STROBE | XDEV_RESUME;
707 				xhci_writel(xhci, temp, addr);
708 
709 				spin_unlock_irqrestore(&xhci->lock, flags);
710 				msleep(20);
711 				spin_lock_irqsave(&xhci->lock, flags);
712 
713 				temp = xhci_readl(xhci, addr);
714 				temp = xhci_port_state_to_neutral(temp);
715 				temp &= ~PORT_PLS_MASK;
716 				temp |= PORT_LINK_STROBE | XDEV_U0;
717 				xhci_writel(xhci, temp, addr);
718 			}
719 			slot_id = xhci_find_slot_id_by_port(xhci, port + 1);
720 			if (slot_id)
721 				xhci_ring_device(xhci, slot_id);
722 		} else
723 			xhci_writel(xhci, temp, addr);
724 
725 		if (DEV_HIGHSPEED(temp)) {
726 			/* disable remote wake up for USB 2.0 */
727 			u32 __iomem *addr;
728 			u32 tmp;
729 
730 			addr = &xhci->op_regs->port_power_base +
731 				NUM_PORT_REGS * (port & 0xff);
732 			tmp = xhci_readl(xhci, addr);
733 			tmp &= ~PORT_RWE;
734 			xhci_writel(xhci, tmp, addr);
735 		}
736 	}
737 
738 	(void) xhci_readl(xhci, &xhci->op_regs->command);
739 
740 	xhci->next_statechange = jiffies + msecs_to_jiffies(5);
741 	hcd->state = HC_STATE_RUNNING;
742 	/* re-enable irqs */
743 	temp = xhci_readl(xhci, &xhci->op_regs->command);
744 	temp |= CMD_EIE;
745 	xhci_writel(xhci, temp, &xhci->op_regs->command);
746 	temp = xhci_readl(xhci, &xhci->op_regs->command);
747 
748 	spin_unlock_irqrestore(&xhci->lock, flags);
749 	return 0;
750 }
751 
752 #endif	/* CONFIG_PM */
753