xref: /openbmc/linux/drivers/usb/host/xhci-pci.c (revision 6f69e2a3)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * xHCI host controller driver PCI Bus Glue.
4  *
5  * Copyright (C) 2008 Intel Corp.
6  *
7  * Author: Sarah Sharp
8  * Some code borrowed from the Linux EHCI driver.
9  */
10 
11 #include <linux/pci.h>
12 #include <linux/slab.h>
13 #include <linux/module.h>
14 #include <linux/acpi.h>
15 
16 #include "xhci.h"
17 #include "xhci-trace.h"
18 
19 #define SSIC_PORT_NUM		2
20 #define SSIC_PORT_CFG2		0x880c
21 #define SSIC_PORT_CFG2_OFFSET	0x30
22 #define PROG_DONE		(1 << 30)
23 #define SSIC_PORT_UNUSED	(1 << 31)
24 
25 /* Device for a quirk */
26 #define PCI_VENDOR_ID_FRESCO_LOGIC	0x1b73
27 #define PCI_DEVICE_ID_FRESCO_LOGIC_PDK	0x1000
28 #define PCI_DEVICE_ID_FRESCO_LOGIC_FL1009	0x1009
29 #define PCI_DEVICE_ID_FRESCO_LOGIC_FL1400	0x1400
30 
31 #define PCI_VENDOR_ID_ETRON		0x1b6f
32 #define PCI_DEVICE_ID_EJ168		0x7023
33 
34 #define PCI_DEVICE_ID_INTEL_LYNXPOINT_XHCI	0x8c31
35 #define PCI_DEVICE_ID_INTEL_LYNXPOINT_LP_XHCI	0x9c31
36 #define PCI_DEVICE_ID_INTEL_WILDCATPOINT_LP_XHCI	0x9cb1
37 #define PCI_DEVICE_ID_INTEL_CHERRYVIEW_XHCI		0x22b5
38 #define PCI_DEVICE_ID_INTEL_SUNRISEPOINT_H_XHCI		0xa12f
39 #define PCI_DEVICE_ID_INTEL_SUNRISEPOINT_LP_XHCI	0x9d2f
40 #define PCI_DEVICE_ID_INTEL_BROXTON_M_XHCI		0x0aa8
41 #define PCI_DEVICE_ID_INTEL_BROXTON_B_XHCI		0x1aa8
42 #define PCI_DEVICE_ID_INTEL_APL_XHCI			0x5aa8
43 #define PCI_DEVICE_ID_INTEL_DNV_XHCI			0x19d0
44 #define PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_2C_XHCI	0x15b5
45 #define PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_4C_XHCI	0x15b6
46 #define PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_C_2C_XHCI	0x15db
47 #define PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_C_4C_XHCI	0x15d4
48 #define PCI_DEVICE_ID_INTEL_TITAN_RIDGE_2C_XHCI		0x15e9
49 #define PCI_DEVICE_ID_INTEL_TITAN_RIDGE_4C_XHCI		0x15ec
50 #define PCI_DEVICE_ID_INTEL_TITAN_RIDGE_DD_XHCI		0x15f0
51 #define PCI_DEVICE_ID_INTEL_ICE_LAKE_XHCI		0x8a13
52 
53 #define PCI_DEVICE_ID_AMD_PROMONTORYA_4			0x43b9
54 #define PCI_DEVICE_ID_AMD_PROMONTORYA_3			0x43ba
55 #define PCI_DEVICE_ID_AMD_PROMONTORYA_2			0x43bb
56 #define PCI_DEVICE_ID_AMD_PROMONTORYA_1			0x43bc
57 #define PCI_DEVICE_ID_ASMEDIA_1042A_XHCI		0x1142
58 
59 static const char hcd_name[] = "xhci_hcd";
60 
61 static struct hc_driver __read_mostly xhci_pci_hc_driver;
62 
63 static int xhci_pci_setup(struct usb_hcd *hcd);
64 
65 static const struct xhci_driver_overrides xhci_pci_overrides __initconst = {
66 	.reset = xhci_pci_setup,
67 };
68 
69 /* called after powerup, by probe or system-pm "wakeup" */
70 static int xhci_pci_reinit(struct xhci_hcd *xhci, struct pci_dev *pdev)
71 {
72 	/*
73 	 * TODO: Implement finding debug ports later.
74 	 * TODO: see if there are any quirks that need to be added to handle
75 	 * new extended capabilities.
76 	 */
77 
78 	/* PCI Memory-Write-Invalidate cycle support is optional (uncommon) */
79 	if (!pci_set_mwi(pdev))
80 		xhci_dbg(xhci, "MWI active\n");
81 
82 	xhci_dbg(xhci, "Finished xhci_pci_reinit\n");
83 	return 0;
84 }
85 
86 static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
87 {
88 	struct pci_dev		*pdev = to_pci_dev(dev);
89 
90 	/* Look for vendor-specific quirks */
91 	if (pdev->vendor == PCI_VENDOR_ID_FRESCO_LOGIC &&
92 			(pdev->device == PCI_DEVICE_ID_FRESCO_LOGIC_PDK ||
93 			 pdev->device == PCI_DEVICE_ID_FRESCO_LOGIC_FL1400)) {
94 		if (pdev->device == PCI_DEVICE_ID_FRESCO_LOGIC_PDK &&
95 				pdev->revision == 0x0) {
96 			xhci->quirks |= XHCI_RESET_EP_QUIRK;
97 			xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
98 				"QUIRK: Fresco Logic xHC needs configure"
99 				" endpoint cmd after reset endpoint");
100 		}
101 		if (pdev->device == PCI_DEVICE_ID_FRESCO_LOGIC_PDK &&
102 				pdev->revision == 0x4) {
103 			xhci->quirks |= XHCI_SLOW_SUSPEND;
104 			xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
105 				"QUIRK: Fresco Logic xHC revision %u"
106 				"must be suspended extra slowly",
107 				pdev->revision);
108 		}
109 		if (pdev->device == PCI_DEVICE_ID_FRESCO_LOGIC_PDK)
110 			xhci->quirks |= XHCI_BROKEN_STREAMS;
111 		/* Fresco Logic confirms: all revisions of this chip do not
112 		 * support MSI, even though some of them claim to in their PCI
113 		 * capabilities.
114 		 */
115 		xhci->quirks |= XHCI_BROKEN_MSI;
116 		xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
117 				"QUIRK: Fresco Logic revision %u "
118 				"has broken MSI implementation",
119 				pdev->revision);
120 		xhci->quirks |= XHCI_TRUST_TX_LENGTH;
121 	}
122 
123 	if (pdev->vendor == PCI_VENDOR_ID_FRESCO_LOGIC &&
124 			pdev->device == PCI_DEVICE_ID_FRESCO_LOGIC_FL1009)
125 		xhci->quirks |= XHCI_BROKEN_STREAMS;
126 
127 	if (pdev->vendor == PCI_VENDOR_ID_NEC)
128 		xhci->quirks |= XHCI_NEC_HOST;
129 
130 	if (pdev->vendor == PCI_VENDOR_ID_AMD && xhci->hci_version == 0x96)
131 		xhci->quirks |= XHCI_AMD_0x96_HOST;
132 
133 	/* AMD PLL quirk */
134 	if (pdev->vendor == PCI_VENDOR_ID_AMD && usb_amd_quirk_pll_check())
135 		xhci->quirks |= XHCI_AMD_PLL_FIX;
136 
137 	if (pdev->vendor == PCI_VENDOR_ID_AMD &&
138 		(pdev->device == 0x15e0 ||
139 		 pdev->device == 0x15e1 ||
140 		 pdev->device == 0x43bb))
141 		xhci->quirks |= XHCI_SUSPEND_DELAY;
142 
143 	if (pdev->vendor == PCI_VENDOR_ID_AMD &&
144 	    (pdev->device == 0x15e0 || pdev->device == 0x15e1))
145 		xhci->quirks |= XHCI_SNPS_BROKEN_SUSPEND;
146 
147 	if (pdev->vendor == PCI_VENDOR_ID_AMD)
148 		xhci->quirks |= XHCI_TRUST_TX_LENGTH;
149 
150 	if ((pdev->vendor == PCI_VENDOR_ID_AMD) &&
151 		((pdev->device == PCI_DEVICE_ID_AMD_PROMONTORYA_4) ||
152 		(pdev->device == PCI_DEVICE_ID_AMD_PROMONTORYA_3) ||
153 		(pdev->device == PCI_DEVICE_ID_AMD_PROMONTORYA_2) ||
154 		(pdev->device == PCI_DEVICE_ID_AMD_PROMONTORYA_1)))
155 		xhci->quirks |= XHCI_U2_DISABLE_WAKE;
156 
157 	if (pdev->vendor == PCI_VENDOR_ID_INTEL) {
158 		xhci->quirks |= XHCI_LPM_SUPPORT;
159 		xhci->quirks |= XHCI_INTEL_HOST;
160 		xhci->quirks |= XHCI_AVOID_BEI;
161 	}
162 	if (pdev->vendor == PCI_VENDOR_ID_INTEL &&
163 			pdev->device == PCI_DEVICE_ID_INTEL_PANTHERPOINT_XHCI) {
164 		xhci->quirks |= XHCI_EP_LIMIT_QUIRK;
165 		xhci->limit_active_eps = 64;
166 		xhci->quirks |= XHCI_SW_BW_CHECKING;
167 		/*
168 		 * PPT desktop boards DH77EB and DH77DF will power back on after
169 		 * a few seconds of being shutdown.  The fix for this is to
170 		 * switch the ports from xHCI to EHCI on shutdown.  We can't use
171 		 * DMI information to find those particular boards (since each
172 		 * vendor will change the board name), so we have to key off all
173 		 * PPT chipsets.
174 		 */
175 		xhci->quirks |= XHCI_SPURIOUS_REBOOT;
176 	}
177 	if (pdev->vendor == PCI_VENDOR_ID_INTEL &&
178 		(pdev->device == PCI_DEVICE_ID_INTEL_LYNXPOINT_LP_XHCI ||
179 		 pdev->device == PCI_DEVICE_ID_INTEL_WILDCATPOINT_LP_XHCI)) {
180 		xhci->quirks |= XHCI_SPURIOUS_REBOOT;
181 		xhci->quirks |= XHCI_SPURIOUS_WAKEUP;
182 	}
183 	if (pdev->vendor == PCI_VENDOR_ID_INTEL &&
184 		(pdev->device == PCI_DEVICE_ID_INTEL_SUNRISEPOINT_LP_XHCI ||
185 		 pdev->device == PCI_DEVICE_ID_INTEL_SUNRISEPOINT_H_XHCI ||
186 		 pdev->device == PCI_DEVICE_ID_INTEL_CHERRYVIEW_XHCI ||
187 		 pdev->device == PCI_DEVICE_ID_INTEL_BROXTON_M_XHCI ||
188 		 pdev->device == PCI_DEVICE_ID_INTEL_BROXTON_B_XHCI ||
189 		 pdev->device == PCI_DEVICE_ID_INTEL_APL_XHCI ||
190 		 pdev->device == PCI_DEVICE_ID_INTEL_DNV_XHCI)) {
191 		xhci->quirks |= XHCI_PME_STUCK_QUIRK;
192 	}
193 	if (pdev->vendor == PCI_VENDOR_ID_INTEL &&
194 	    pdev->device == PCI_DEVICE_ID_INTEL_CHERRYVIEW_XHCI)
195 		xhci->quirks |= XHCI_SSIC_PORT_UNUSED;
196 	if (pdev->vendor == PCI_VENDOR_ID_INTEL &&
197 	    (pdev->device == PCI_DEVICE_ID_INTEL_CHERRYVIEW_XHCI ||
198 	     pdev->device == PCI_DEVICE_ID_INTEL_SUNRISEPOINT_LP_XHCI ||
199 	     pdev->device == PCI_DEVICE_ID_INTEL_APL_XHCI))
200 		xhci->quirks |= XHCI_INTEL_USB_ROLE_SW;
201 	if (pdev->vendor == PCI_VENDOR_ID_INTEL &&
202 	    (pdev->device == PCI_DEVICE_ID_INTEL_CHERRYVIEW_XHCI ||
203 	     pdev->device == PCI_DEVICE_ID_INTEL_SUNRISEPOINT_LP_XHCI ||
204 	     pdev->device == PCI_DEVICE_ID_INTEL_SUNRISEPOINT_H_XHCI ||
205 	     pdev->device == PCI_DEVICE_ID_INTEL_APL_XHCI ||
206 	     pdev->device == PCI_DEVICE_ID_INTEL_DNV_XHCI))
207 		xhci->quirks |= XHCI_MISSING_CAS;
208 
209 	if (pdev->vendor == PCI_VENDOR_ID_INTEL &&
210 	    (pdev->device == PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_2C_XHCI ||
211 	     pdev->device == PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_4C_XHCI ||
212 	     pdev->device == PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_C_2C_XHCI ||
213 	     pdev->device == PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_C_4C_XHCI ||
214 	     pdev->device == PCI_DEVICE_ID_INTEL_TITAN_RIDGE_2C_XHCI ||
215 	     pdev->device == PCI_DEVICE_ID_INTEL_TITAN_RIDGE_4C_XHCI ||
216 	     pdev->device == PCI_DEVICE_ID_INTEL_TITAN_RIDGE_DD_XHCI ||
217 	     pdev->device == PCI_DEVICE_ID_INTEL_ICE_LAKE_XHCI))
218 		xhci->quirks |= XHCI_DEFAULT_PM_RUNTIME_ALLOW;
219 
220 	if (pdev->vendor == PCI_VENDOR_ID_ETRON &&
221 			pdev->device == PCI_DEVICE_ID_EJ168) {
222 		xhci->quirks |= XHCI_RESET_ON_RESUME;
223 		xhci->quirks |= XHCI_TRUST_TX_LENGTH;
224 		xhci->quirks |= XHCI_BROKEN_STREAMS;
225 	}
226 	if (pdev->vendor == PCI_VENDOR_ID_RENESAS &&
227 	    pdev->device == 0x0014) {
228 		xhci->quirks |= XHCI_TRUST_TX_LENGTH;
229 		xhci->quirks |= XHCI_ZERO_64B_REGS;
230 	}
231 	if (pdev->vendor == PCI_VENDOR_ID_RENESAS &&
232 	    pdev->device == 0x0015) {
233 		xhci->quirks |= XHCI_RESET_ON_RESUME;
234 		xhci->quirks |= XHCI_ZERO_64B_REGS;
235 	}
236 	if (pdev->vendor == PCI_VENDOR_ID_VIA)
237 		xhci->quirks |= XHCI_RESET_ON_RESUME;
238 
239 	/* See https://bugzilla.kernel.org/show_bug.cgi?id=79511 */
240 	if (pdev->vendor == PCI_VENDOR_ID_VIA &&
241 			pdev->device == 0x3432)
242 		xhci->quirks |= XHCI_BROKEN_STREAMS;
243 
244 	if (pdev->vendor == PCI_VENDOR_ID_ASMEDIA &&
245 			pdev->device == 0x1042)
246 		xhci->quirks |= XHCI_BROKEN_STREAMS;
247 	if (pdev->vendor == PCI_VENDOR_ID_ASMEDIA &&
248 			pdev->device == 0x1142)
249 		xhci->quirks |= XHCI_TRUST_TX_LENGTH;
250 
251 	if (pdev->vendor == PCI_VENDOR_ID_ASMEDIA &&
252 		pdev->device == PCI_DEVICE_ID_ASMEDIA_1042A_XHCI)
253 		xhci->quirks |= XHCI_ASMEDIA_MODIFY_FLOWCONTROL;
254 
255 	if (pdev->vendor == PCI_VENDOR_ID_TI && pdev->device == 0x8241)
256 		xhci->quirks |= XHCI_LIMIT_ENDPOINT_INTERVAL_7;
257 
258 	if ((pdev->vendor == PCI_VENDOR_ID_BROADCOM ||
259 	     pdev->vendor == PCI_VENDOR_ID_CAVIUM) &&
260 	     pdev->device == 0x9026)
261 		xhci->quirks |= XHCI_RESET_PLL_ON_DISCONNECT;
262 
263 	if (xhci->quirks & XHCI_RESET_ON_RESUME)
264 		xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
265 				"QUIRK: Resetting on resume");
266 }
267 
268 #ifdef CONFIG_ACPI
269 static void xhci_pme_acpi_rtd3_enable(struct pci_dev *dev)
270 {
271 	static const guid_t intel_dsm_guid =
272 		GUID_INIT(0xac340cb7, 0xe901, 0x45bf,
273 			  0xb7, 0xe6, 0x2b, 0x34, 0xec, 0x93, 0x1e, 0x23);
274 	union acpi_object *obj;
275 
276 	obj = acpi_evaluate_dsm(ACPI_HANDLE(&dev->dev), &intel_dsm_guid, 3, 1,
277 				NULL);
278 	ACPI_FREE(obj);
279 }
280 #else
281 static void xhci_pme_acpi_rtd3_enable(struct pci_dev *dev) { }
282 #endif /* CONFIG_ACPI */
283 
284 /* called during probe() after chip reset completes */
285 static int xhci_pci_setup(struct usb_hcd *hcd)
286 {
287 	struct xhci_hcd		*xhci;
288 	struct pci_dev		*pdev = to_pci_dev(hcd->self.controller);
289 	int			retval;
290 
291 	xhci = hcd_to_xhci(hcd);
292 	if (!xhci->sbrn)
293 		pci_read_config_byte(pdev, XHCI_SBRN_OFFSET, &xhci->sbrn);
294 
295 	/* imod_interval is the interrupt moderation value in nanoseconds. */
296 	xhci->imod_interval = 40000;
297 
298 	retval = xhci_gen_setup(hcd, xhci_pci_quirks);
299 	if (retval)
300 		return retval;
301 
302 	if (!usb_hcd_is_primary_hcd(hcd))
303 		return 0;
304 
305 	xhci_dbg(xhci, "Got SBRN %u\n", (unsigned int) xhci->sbrn);
306 
307 	/* Find any debug ports */
308 	return xhci_pci_reinit(xhci, pdev);
309 }
310 
311 /*
312  * We need to register our own PCI probe function (instead of the USB core's
313  * function) in order to create a second roothub under xHCI.
314  */
315 static int xhci_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
316 {
317 	int retval;
318 	struct xhci_hcd *xhci;
319 	struct hc_driver *driver;
320 	struct usb_hcd *hcd;
321 
322 	driver = (struct hc_driver *)id->driver_data;
323 
324 	/* Prevent runtime suspending between USB-2 and USB-3 initialization */
325 	pm_runtime_get_noresume(&dev->dev);
326 
327 	/* Register the USB 2.0 roothub.
328 	 * FIXME: USB core must know to register the USB 2.0 roothub first.
329 	 * This is sort of silly, because we could just set the HCD driver flags
330 	 * to say USB 2.0, but I'm not sure what the implications would be in
331 	 * the other parts of the HCD code.
332 	 */
333 	retval = usb_hcd_pci_probe(dev, id);
334 
335 	if (retval)
336 		goto put_runtime_pm;
337 
338 	/* USB 2.0 roothub is stored in the PCI device now. */
339 	hcd = dev_get_drvdata(&dev->dev);
340 	xhci = hcd_to_xhci(hcd);
341 	xhci->shared_hcd = usb_create_shared_hcd(driver, &dev->dev,
342 				pci_name(dev), hcd);
343 	if (!xhci->shared_hcd) {
344 		retval = -ENOMEM;
345 		goto dealloc_usb2_hcd;
346 	}
347 
348 	retval = xhci_ext_cap_init(xhci);
349 	if (retval)
350 		goto put_usb3_hcd;
351 
352 	retval = usb_add_hcd(xhci->shared_hcd, dev->irq,
353 			IRQF_SHARED);
354 	if (retval)
355 		goto put_usb3_hcd;
356 	/* Roothub already marked as USB 3.0 speed */
357 
358 	if (!(xhci->quirks & XHCI_BROKEN_STREAMS) &&
359 			HCC_MAX_PSA(xhci->hcc_params) >= 4)
360 		xhci->shared_hcd->can_do_streams = 1;
361 
362 	if (xhci->quirks & XHCI_PME_STUCK_QUIRK)
363 		xhci_pme_acpi_rtd3_enable(dev);
364 
365 	/* USB-2 and USB-3 roothubs initialized, allow runtime pm suspend */
366 	pm_runtime_put_noidle(&dev->dev);
367 
368 	if (xhci->quirks & XHCI_DEFAULT_PM_RUNTIME_ALLOW)
369 		pm_runtime_allow(&dev->dev);
370 
371 	return 0;
372 
373 put_usb3_hcd:
374 	usb_put_hcd(xhci->shared_hcd);
375 dealloc_usb2_hcd:
376 	usb_hcd_pci_remove(dev);
377 put_runtime_pm:
378 	pm_runtime_put_noidle(&dev->dev);
379 	return retval;
380 }
381 
382 static void xhci_pci_remove(struct pci_dev *dev)
383 {
384 	struct xhci_hcd *xhci;
385 
386 	xhci = hcd_to_xhci(pci_get_drvdata(dev));
387 	xhci->xhc_state |= XHCI_STATE_REMOVING;
388 
389 	if (xhci->quirks & XHCI_DEFAULT_PM_RUNTIME_ALLOW)
390 		pm_runtime_forbid(&dev->dev);
391 
392 	if (xhci->shared_hcd) {
393 		usb_remove_hcd(xhci->shared_hcd);
394 		usb_put_hcd(xhci->shared_hcd);
395 		xhci->shared_hcd = NULL;
396 	}
397 
398 	/* Workaround for spurious wakeups at shutdown with HSW */
399 	if (xhci->quirks & XHCI_SPURIOUS_WAKEUP)
400 		pci_set_power_state(dev, PCI_D3hot);
401 
402 	usb_hcd_pci_remove(dev);
403 }
404 
405 #ifdef CONFIG_PM
406 /*
407  * In some Intel xHCI controllers, in order to get D3 working,
408  * through a vendor specific SSIC CONFIG register at offset 0x883c,
409  * SSIC PORT need to be marked as "unused" before putting xHCI
410  * into D3. After D3 exit, the SSIC port need to be marked as "used".
411  * Without this change, xHCI might not enter D3 state.
412  */
413 static void xhci_ssic_port_unused_quirk(struct usb_hcd *hcd, bool suspend)
414 {
415 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
416 	u32 val;
417 	void __iomem *reg;
418 	int i;
419 
420 	for (i = 0; i < SSIC_PORT_NUM; i++) {
421 		reg = (void __iomem *) xhci->cap_regs +
422 				SSIC_PORT_CFG2 +
423 				i * SSIC_PORT_CFG2_OFFSET;
424 
425 		/* Notify SSIC that SSIC profile programming is not done. */
426 		val = readl(reg) & ~PROG_DONE;
427 		writel(val, reg);
428 
429 		/* Mark SSIC port as unused(suspend) or used(resume) */
430 		val = readl(reg);
431 		if (suspend)
432 			val |= SSIC_PORT_UNUSED;
433 		else
434 			val &= ~SSIC_PORT_UNUSED;
435 		writel(val, reg);
436 
437 		/* Notify SSIC that SSIC profile programming is done */
438 		val = readl(reg) | PROG_DONE;
439 		writel(val, reg);
440 		readl(reg);
441 	}
442 }
443 
444 /*
445  * Make sure PME works on some Intel xHCI controllers by writing 1 to clear
446  * the Internal PME flag bit in vendor specific PMCTRL register at offset 0x80a4
447  */
448 static void xhci_pme_quirk(struct usb_hcd *hcd)
449 {
450 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
451 	void __iomem *reg;
452 	u32 val;
453 
454 	reg = (void __iomem *) xhci->cap_regs + 0x80a4;
455 	val = readl(reg);
456 	writel(val | BIT(28), reg);
457 	readl(reg);
458 }
459 
460 static int xhci_pci_suspend(struct usb_hcd *hcd, bool do_wakeup)
461 {
462 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
463 	struct pci_dev		*pdev = to_pci_dev(hcd->self.controller);
464 	int			ret;
465 
466 	/*
467 	 * Systems with the TI redriver that loses port status change events
468 	 * need to have the registers polled during D3, so avoid D3cold.
469 	 */
470 	if (xhci->quirks & XHCI_COMP_MODE_QUIRK)
471 		pci_d3cold_disable(pdev);
472 
473 	if (xhci->quirks & XHCI_PME_STUCK_QUIRK)
474 		xhci_pme_quirk(hcd);
475 
476 	if (xhci->quirks & XHCI_SSIC_PORT_UNUSED)
477 		xhci_ssic_port_unused_quirk(hcd, true);
478 
479 	ret = xhci_suspend(xhci, do_wakeup);
480 	if (ret && (xhci->quirks & XHCI_SSIC_PORT_UNUSED))
481 		xhci_ssic_port_unused_quirk(hcd, false);
482 
483 	return ret;
484 }
485 
486 static int xhci_pci_resume(struct usb_hcd *hcd, bool hibernated)
487 {
488 	struct xhci_hcd		*xhci = hcd_to_xhci(hcd);
489 	struct pci_dev		*pdev = to_pci_dev(hcd->self.controller);
490 	int			retval = 0;
491 
492 	/* The BIOS on systems with the Intel Panther Point chipset may or may
493 	 * not support xHCI natively.  That means that during system resume, it
494 	 * may switch the ports back to EHCI so that users can use their
495 	 * keyboard to select a kernel from GRUB after resume from hibernate.
496 	 *
497 	 * The BIOS is supposed to remember whether the OS had xHCI ports
498 	 * enabled before resume, and switch the ports back to xHCI when the
499 	 * BIOS/OS semaphore is written, but we all know we can't trust BIOS
500 	 * writers.
501 	 *
502 	 * Unconditionally switch the ports back to xHCI after a system resume.
503 	 * It should not matter whether the EHCI or xHCI controller is
504 	 * resumed first. It's enough to do the switchover in xHCI because
505 	 * USB core won't notice anything as the hub driver doesn't start
506 	 * running again until after all the devices (including both EHCI and
507 	 * xHCI host controllers) have been resumed.
508 	 */
509 
510 	if (pdev->vendor == PCI_VENDOR_ID_INTEL)
511 		usb_enable_intel_xhci_ports(pdev);
512 
513 	if (xhci->quirks & XHCI_SSIC_PORT_UNUSED)
514 		xhci_ssic_port_unused_quirk(hcd, false);
515 
516 	if (xhci->quirks & XHCI_PME_STUCK_QUIRK)
517 		xhci_pme_quirk(hcd);
518 
519 	retval = xhci_resume(xhci, hibernated);
520 	return retval;
521 }
522 #endif /* CONFIG_PM */
523 
524 /*-------------------------------------------------------------------------*/
525 
526 /* PCI driver selection metadata; PCI hotplugging uses this */
527 static const struct pci_device_id pci_ids[] = { {
528 	/* handle any USB 3.0 xHCI controller */
529 	PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_USB_XHCI, ~0),
530 	.driver_data =	(unsigned long) &xhci_pci_hc_driver,
531 	},
532 	{ /* end: all zeroes */ }
533 };
534 MODULE_DEVICE_TABLE(pci, pci_ids);
535 
536 /* pci driver glue; this is a "new style" PCI driver module */
537 static struct pci_driver xhci_pci_driver = {
538 	.name =		(char *) hcd_name,
539 	.id_table =	pci_ids,
540 
541 	.probe =	xhci_pci_probe,
542 	.remove =	xhci_pci_remove,
543 	/* suspend and resume implemented later */
544 
545 	.shutdown = 	usb_hcd_pci_shutdown,
546 #ifdef CONFIG_PM
547 	.driver = {
548 		.pm = &usb_hcd_pci_pm_ops
549 	},
550 #endif
551 };
552 
553 static int __init xhci_pci_init(void)
554 {
555 	xhci_init_driver(&xhci_pci_hc_driver, &xhci_pci_overrides);
556 #ifdef CONFIG_PM
557 	xhci_pci_hc_driver.pci_suspend = xhci_pci_suspend;
558 	xhci_pci_hc_driver.pci_resume = xhci_pci_resume;
559 #endif
560 	return pci_register_driver(&xhci_pci_driver);
561 }
562 module_init(xhci_pci_init);
563 
564 static void __exit xhci_pci_exit(void)
565 {
566 	pci_unregister_driver(&xhci_pci_driver);
567 }
568 module_exit(xhci_pci_exit);
569 
570 MODULE_DESCRIPTION("xHCI PCI Host Controller Driver");
571 MODULE_LICENSE("GPL");
572