xref: /openbmc/linux/drivers/usb/core/hcd-pci.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
1 /*
2  * (C) Copyright David Brownell 2000-2002
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms of the GNU General Public License as published by the
6  * Free Software Foundation; either version 2 of the License, or (at your
7  * option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful, but
10  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
11  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12  * for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software Foundation,
16  * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
17  */
18 
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/pci.h>
22 #include <linux/pm_runtime.h>
23 #include <linux/usb.h>
24 #include <linux/usb/hcd.h>
25 
26 #include <asm/io.h>
27 #include <asm/irq.h>
28 
29 #ifdef CONFIG_PPC_PMAC
30 #include <asm/machdep.h>
31 #include <asm/pmac_feature.h>
32 #include <asm/pci-bridge.h>
33 #include <asm/prom.h>
34 #endif
35 
36 #include "usb.h"
37 
38 
39 /* PCI-based HCs are common, but plenty of non-PCI HCs are used too */
40 
41 #ifdef CONFIG_PM_SLEEP
42 
43 /* Coordinate handoffs between EHCI and companion controllers
44  * during system resume
45  */
46 
47 static DEFINE_MUTEX(companions_mutex);
48 
49 #define CL_UHCI		PCI_CLASS_SERIAL_USB_UHCI
50 #define CL_OHCI		PCI_CLASS_SERIAL_USB_OHCI
51 #define CL_EHCI		PCI_CLASS_SERIAL_USB_EHCI
52 
53 enum companion_action {
54 	SET_HS_COMPANION, CLEAR_HS_COMPANION, WAIT_FOR_COMPANIONS
55 };
56 
57 static void companion_common(struct pci_dev *pdev, struct usb_hcd *hcd,
58 		enum companion_action action)
59 {
60 	struct pci_dev		*companion;
61 	struct usb_hcd		*companion_hcd;
62 	unsigned int		slot = PCI_SLOT(pdev->devfn);
63 
64 	/* Iterate through other PCI functions in the same slot.
65 	 * If pdev is OHCI or UHCI then we are looking for EHCI, and
66 	 * vice versa.
67 	 */
68 	companion = NULL;
69 	for_each_pci_dev(companion) {
70 		if (companion->bus != pdev->bus ||
71 				PCI_SLOT(companion->devfn) != slot)
72 			continue;
73 
74 		companion_hcd = pci_get_drvdata(companion);
75 		if (!companion_hcd)
76 			continue;
77 
78 		/* For SET_HS_COMPANION, store a pointer to the EHCI bus in
79 		 * the OHCI/UHCI companion bus structure.
80 		 * For CLEAR_HS_COMPANION, clear the pointer to the EHCI bus
81 		 * in the OHCI/UHCI companion bus structure.
82 		 * For WAIT_FOR_COMPANIONS, wait until the OHCI/UHCI
83 		 * companion controllers have fully resumed.
84 		 */
85 
86 		if ((pdev->class == CL_OHCI || pdev->class == CL_UHCI) &&
87 				companion->class == CL_EHCI) {
88 			/* action must be SET_HS_COMPANION */
89 			dev_dbg(&companion->dev, "HS companion for %s\n",
90 					dev_name(&pdev->dev));
91 			hcd->self.hs_companion = &companion_hcd->self;
92 
93 		} else if (pdev->class == CL_EHCI &&
94 				(companion->class == CL_OHCI ||
95 				companion->class == CL_UHCI)) {
96 			switch (action) {
97 			case SET_HS_COMPANION:
98 				dev_dbg(&pdev->dev, "HS companion for %s\n",
99 						dev_name(&companion->dev));
100 				companion_hcd->self.hs_companion = &hcd->self;
101 				break;
102 			case CLEAR_HS_COMPANION:
103 				companion_hcd->self.hs_companion = NULL;
104 				break;
105 			case WAIT_FOR_COMPANIONS:
106 				device_pm_wait_for_dev(&pdev->dev,
107 						&companion->dev);
108 				break;
109 			}
110 		}
111 	}
112 }
113 
114 static void set_hs_companion(struct pci_dev *pdev, struct usb_hcd *hcd)
115 {
116 	mutex_lock(&companions_mutex);
117 	dev_set_drvdata(&pdev->dev, hcd);
118 	companion_common(pdev, hcd, SET_HS_COMPANION);
119 	mutex_unlock(&companions_mutex);
120 }
121 
122 static void clear_hs_companion(struct pci_dev *pdev, struct usb_hcd *hcd)
123 {
124 	mutex_lock(&companions_mutex);
125 	dev_set_drvdata(&pdev->dev, NULL);
126 
127 	/* If pdev is OHCI or UHCI, just clear its hs_companion pointer */
128 	if (pdev->class == CL_OHCI || pdev->class == CL_UHCI)
129 		hcd->self.hs_companion = NULL;
130 
131 	/* Otherwise search for companion buses and clear their pointers */
132 	else
133 		companion_common(pdev, hcd, CLEAR_HS_COMPANION);
134 	mutex_unlock(&companions_mutex);
135 }
136 
137 static void wait_for_companions(struct pci_dev *pdev, struct usb_hcd *hcd)
138 {
139 	/* Only EHCI controllers need to wait.
140 	 * No locking is needed because a controller cannot be resumed
141 	 * while one of its companions is getting unbound.
142 	 */
143 	if (pdev->class == CL_EHCI)
144 		companion_common(pdev, hcd, WAIT_FOR_COMPANIONS);
145 }
146 
147 #else /* !CONFIG_PM_SLEEP */
148 
149 static inline void set_hs_companion(struct pci_dev *d, struct usb_hcd *h) {}
150 static inline void clear_hs_companion(struct pci_dev *d, struct usb_hcd *h) {}
151 static inline void wait_for_companions(struct pci_dev *d, struct usb_hcd *h) {}
152 
153 #endif /* !CONFIG_PM_SLEEP */
154 
155 /*-------------------------------------------------------------------------*/
156 
157 /* configure so an HC device and id are always provided */
158 /* always called with process context; sleeping is OK */
159 
160 /**
161  * usb_hcd_pci_probe - initialize PCI-based HCDs
162  * @dev: USB Host Controller being probed
163  * @id: pci hotplug id connecting controller to HCD framework
164  * Context: !in_interrupt()
165  *
166  * Allocates basic PCI resources for this USB host controller, and
167  * then invokes the start() method for the HCD associated with it
168  * through the hotplug entry's driver_data.
169  *
170  * Store this function in the HCD's struct pci_driver as probe().
171  */
172 int usb_hcd_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
173 {
174 	struct hc_driver	*driver;
175 	struct usb_hcd		*hcd;
176 	int			retval;
177 
178 	if (usb_disabled())
179 		return -ENODEV;
180 
181 	if (!id)
182 		return -EINVAL;
183 	driver = (struct hc_driver *)id->driver_data;
184 	if (!driver)
185 		return -EINVAL;
186 
187 	if (pci_enable_device(dev) < 0)
188 		return -ENODEV;
189 	dev->current_state = PCI_D0;
190 
191 	if (!dev->irq) {
192 		dev_err(&dev->dev,
193 			"Found HC with no IRQ.  Check BIOS/PCI %s setup!\n",
194 			pci_name(dev));
195 		retval = -ENODEV;
196 		goto err1;
197 	}
198 
199 	hcd = usb_create_hcd(driver, &dev->dev, pci_name(dev));
200 	if (!hcd) {
201 		retval = -ENOMEM;
202 		goto err1;
203 	}
204 
205 	if (driver->flags & HCD_MEMORY) {
206 		/* EHCI, OHCI */
207 		hcd->rsrc_start = pci_resource_start(dev, 0);
208 		hcd->rsrc_len = pci_resource_len(dev, 0);
209 		if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len,
210 				driver->description)) {
211 			dev_dbg(&dev->dev, "controller already in use\n");
212 			retval = -EBUSY;
213 			goto err2;
214 		}
215 		hcd->regs = ioremap_nocache(hcd->rsrc_start, hcd->rsrc_len);
216 		if (hcd->regs == NULL) {
217 			dev_dbg(&dev->dev, "error mapping memory\n");
218 			retval = -EFAULT;
219 			goto err3;
220 		}
221 
222 	} else {
223 		/* UHCI */
224 		int	region;
225 
226 		for (region = 0; region < PCI_ROM_RESOURCE; region++) {
227 			if (!(pci_resource_flags(dev, region) &
228 					IORESOURCE_IO))
229 				continue;
230 
231 			hcd->rsrc_start = pci_resource_start(dev, region);
232 			hcd->rsrc_len = pci_resource_len(dev, region);
233 			if (request_region(hcd->rsrc_start, hcd->rsrc_len,
234 					driver->description))
235 				break;
236 		}
237 		if (region == PCI_ROM_RESOURCE) {
238 			dev_dbg(&dev->dev, "no i/o regions available\n");
239 			retval = -EBUSY;
240 			goto err2;
241 		}
242 	}
243 
244 	pci_set_master(dev);
245 
246 	retval = usb_add_hcd(hcd, dev->irq, IRQF_DISABLED | IRQF_SHARED);
247 	if (retval != 0)
248 		goto err4;
249 	set_hs_companion(dev, hcd);
250 
251 	if (pci_dev_run_wake(dev))
252 		pm_runtime_put_noidle(&dev->dev);
253 	return retval;
254 
255  err4:
256 	if (driver->flags & HCD_MEMORY) {
257 		iounmap(hcd->regs);
258  err3:
259 		release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
260 	} else
261 		release_region(hcd->rsrc_start, hcd->rsrc_len);
262  err2:
263 	clear_hs_companion(dev, hcd);
264 	usb_put_hcd(hcd);
265  err1:
266 	pci_disable_device(dev);
267 	dev_err(&dev->dev, "init %s fail, %d\n", pci_name(dev), retval);
268 	return retval;
269 }
270 EXPORT_SYMBOL_GPL(usb_hcd_pci_probe);
271 
272 
273 /* may be called without controller electrically present */
274 /* may be called with controller, bus, and devices active */
275 
276 /**
277  * usb_hcd_pci_remove - shutdown processing for PCI-based HCDs
278  * @dev: USB Host Controller being removed
279  * Context: !in_interrupt()
280  *
281  * Reverses the effect of usb_hcd_pci_probe(), first invoking
282  * the HCD's stop() method.  It is always called from a thread
283  * context, normally "rmmod", "apmd", or something similar.
284  *
285  * Store this function in the HCD's struct pci_driver as remove().
286  */
287 void usb_hcd_pci_remove(struct pci_dev *dev)
288 {
289 	struct usb_hcd		*hcd;
290 
291 	hcd = pci_get_drvdata(dev);
292 	if (!hcd)
293 		return;
294 
295 	if (pci_dev_run_wake(dev))
296 		pm_runtime_get_noresume(&dev->dev);
297 
298 	/* Fake an interrupt request in order to give the driver a chance
299 	 * to test whether the controller hardware has been removed (e.g.,
300 	 * cardbus physical eject).
301 	 */
302 	local_irq_disable();
303 	usb_hcd_irq(0, hcd);
304 	local_irq_enable();
305 
306 	usb_remove_hcd(hcd);
307 	if (hcd->driver->flags & HCD_MEMORY) {
308 		iounmap(hcd->regs);
309 		release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
310 	} else {
311 		release_region(hcd->rsrc_start, hcd->rsrc_len);
312 	}
313 	clear_hs_companion(dev, hcd);
314 	usb_put_hcd(hcd);
315 	pci_disable_device(dev);
316 }
317 EXPORT_SYMBOL_GPL(usb_hcd_pci_remove);
318 
319 /**
320  * usb_hcd_pci_shutdown - shutdown host controller
321  * @dev: USB Host Controller being shutdown
322  */
323 void usb_hcd_pci_shutdown(struct pci_dev *dev)
324 {
325 	struct usb_hcd		*hcd;
326 
327 	hcd = pci_get_drvdata(dev);
328 	if (!hcd)
329 		return;
330 
331 	if (test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags) &&
332 			hcd->driver->shutdown) {
333 		hcd->driver->shutdown(hcd);
334 		pci_disable_device(dev);
335 	}
336 }
337 EXPORT_SYMBOL_GPL(usb_hcd_pci_shutdown);
338 
339 #ifdef	CONFIG_PM_OPS
340 
341 #ifdef	CONFIG_PPC_PMAC
342 static void powermac_set_asic(struct pci_dev *pci_dev, int enable)
343 {
344 	/* Enanble or disable ASIC clocks for USB */
345 	if (machine_is(powermac)) {
346 		struct device_node	*of_node;
347 
348 		of_node = pci_device_to_OF_node(pci_dev);
349 		if (of_node)
350 			pmac_call_feature(PMAC_FTR_USB_ENABLE,
351 					of_node, 0, enable);
352 	}
353 }
354 
355 #else
356 
357 static inline void powermac_set_asic(struct pci_dev *pci_dev, int enable)
358 {}
359 
360 #endif	/* CONFIG_PPC_PMAC */
361 
362 static int check_root_hub_suspended(struct device *dev)
363 {
364 	struct pci_dev		*pci_dev = to_pci_dev(dev);
365 	struct usb_hcd		*hcd = pci_get_drvdata(pci_dev);
366 
367 	if (!(hcd->state == HC_STATE_SUSPENDED ||
368 			hcd->state == HC_STATE_HALT)) {
369 		dev_warn(dev, "Root hub is not suspended\n");
370 		return -EBUSY;
371 	}
372 	return 0;
373 }
374 
375 static int suspend_common(struct device *dev, bool do_wakeup)
376 {
377 	struct pci_dev		*pci_dev = to_pci_dev(dev);
378 	struct usb_hcd		*hcd = pci_get_drvdata(pci_dev);
379 	int			retval;
380 
381 	/* Root hub suspend should have stopped all downstream traffic,
382 	 * and all bus master traffic.  And done so for both the interface
383 	 * and the stub usb_device (which we check here).  But maybe it
384 	 * didn't; writing sysfs power/state files ignores such rules...
385 	 */
386 	retval = check_root_hub_suspended(dev);
387 	if (retval)
388 		return retval;
389 
390 	if (hcd->driver->pci_suspend) {
391 		/* Optimization: Don't suspend if a root-hub wakeup is
392 		 * pending and it would cause the HCD to wake up anyway.
393 		 */
394 		if (do_wakeup && HCD_WAKEUP_PENDING(hcd))
395 			return -EBUSY;
396 		retval = hcd->driver->pci_suspend(hcd, do_wakeup);
397 		suspend_report_result(hcd->driver->pci_suspend, retval);
398 
399 		/* Check again in case wakeup raced with pci_suspend */
400 		if (retval == 0 && do_wakeup && HCD_WAKEUP_PENDING(hcd)) {
401 			if (hcd->driver->pci_resume)
402 				hcd->driver->pci_resume(hcd, false);
403 			retval = -EBUSY;
404 		}
405 		if (retval)
406 			return retval;
407 	}
408 
409 	synchronize_irq(pci_dev->irq);
410 
411 	/* Downstream ports from this root hub should already be quiesced, so
412 	 * there will be no DMA activity.  Now we can shut down the upstream
413 	 * link (except maybe for PME# resume signaling).  We'll enter a
414 	 * low power state during suspend_noirq, if the hardware allows.
415 	 */
416 	pci_disable_device(pci_dev);
417 	return retval;
418 }
419 
420 static int resume_common(struct device *dev, int event)
421 {
422 	struct pci_dev		*pci_dev = to_pci_dev(dev);
423 	struct usb_hcd		*hcd = pci_get_drvdata(pci_dev);
424 	int			retval;
425 
426 	if (hcd->state != HC_STATE_SUSPENDED) {
427 		dev_dbg(dev, "can't resume, not suspended!\n");
428 		return 0;
429 	}
430 
431 	retval = pci_enable_device(pci_dev);
432 	if (retval < 0) {
433 		dev_err(dev, "can't re-enable after resume, %d!\n", retval);
434 		return retval;
435 	}
436 
437 	pci_set_master(pci_dev);
438 
439 	clear_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
440 
441 	if (hcd->driver->pci_resume) {
442 		if (event != PM_EVENT_AUTO_RESUME)
443 			wait_for_companions(pci_dev, hcd);
444 
445 		retval = hcd->driver->pci_resume(hcd,
446 				event == PM_EVENT_RESTORE);
447 		if (retval) {
448 			dev_err(dev, "PCI post-resume error %d!\n", retval);
449 			usb_hc_died(hcd);
450 		}
451 	}
452 	return retval;
453 }
454 
455 #ifdef	CONFIG_PM_SLEEP
456 
457 static int hcd_pci_suspend(struct device *dev)
458 {
459 	return suspend_common(dev, device_may_wakeup(dev));
460 }
461 
462 static int hcd_pci_suspend_noirq(struct device *dev)
463 {
464 	struct pci_dev		*pci_dev = to_pci_dev(dev);
465 	struct usb_hcd		*hcd = pci_get_drvdata(pci_dev);
466 	int			retval;
467 
468 	retval = check_root_hub_suspended(dev);
469 	if (retval)
470 		return retval;
471 
472 	pci_save_state(pci_dev);
473 
474 	/* If the root hub is HALTed rather than SUSPENDed,
475 	 * disallow remote wakeup.
476 	 */
477 	if (hcd->state == HC_STATE_HALT)
478 		device_set_wakeup_enable(dev, 0);
479 	dev_dbg(dev, "wakeup: %d\n", device_may_wakeup(dev));
480 
481 	/* Possibly enable remote wakeup,
482 	 * choose the appropriate low-power state, and go to that state.
483 	 */
484 	retval = pci_prepare_to_sleep(pci_dev);
485 	if (retval == -EIO) {		/* Low-power not supported */
486 		dev_dbg(dev, "--> PCI D0 legacy\n");
487 		retval = 0;
488 	} else if (retval == 0) {
489 		dev_dbg(dev, "--> PCI %s\n",
490 				pci_power_name(pci_dev->current_state));
491 	} else {
492 		suspend_report_result(pci_prepare_to_sleep, retval);
493 		return retval;
494 	}
495 
496 	powermac_set_asic(pci_dev, 0);
497 	return retval;
498 }
499 
500 static int hcd_pci_resume_noirq(struct device *dev)
501 {
502 	struct pci_dev		*pci_dev = to_pci_dev(dev);
503 
504 	powermac_set_asic(pci_dev, 1);
505 
506 	/* Go back to D0 and disable remote wakeup */
507 	pci_back_from_sleep(pci_dev);
508 	return 0;
509 }
510 
511 static int hcd_pci_resume(struct device *dev)
512 {
513 	return resume_common(dev, PM_EVENT_RESUME);
514 }
515 
516 static int hcd_pci_restore(struct device *dev)
517 {
518 	return resume_common(dev, PM_EVENT_RESTORE);
519 }
520 
521 #else
522 
523 #define hcd_pci_suspend		NULL
524 #define hcd_pci_suspend_noirq	NULL
525 #define hcd_pci_resume_noirq	NULL
526 #define hcd_pci_resume		NULL
527 #define hcd_pci_restore		NULL
528 
529 #endif	/* CONFIG_PM_SLEEP */
530 
531 #ifdef	CONFIG_PM_RUNTIME
532 
533 static int hcd_pci_runtime_suspend(struct device *dev)
534 {
535 	int	retval;
536 
537 	retval = suspend_common(dev, true);
538 	if (retval == 0)
539 		powermac_set_asic(to_pci_dev(dev), 0);
540 	dev_dbg(dev, "hcd_pci_runtime_suspend: %d\n", retval);
541 	return retval;
542 }
543 
544 static int hcd_pci_runtime_resume(struct device *dev)
545 {
546 	int	retval;
547 
548 	powermac_set_asic(to_pci_dev(dev), 1);
549 	retval = resume_common(dev, PM_EVENT_AUTO_RESUME);
550 	dev_dbg(dev, "hcd_pci_runtime_resume: %d\n", retval);
551 	return retval;
552 }
553 
554 #else
555 
556 #define hcd_pci_runtime_suspend	NULL
557 #define hcd_pci_runtime_resume	NULL
558 
559 #endif	/* CONFIG_PM_RUNTIME */
560 
561 const struct dev_pm_ops usb_hcd_pci_pm_ops = {
562 	.suspend	= hcd_pci_suspend,
563 	.suspend_noirq	= hcd_pci_suspend_noirq,
564 	.resume_noirq	= hcd_pci_resume_noirq,
565 	.resume		= hcd_pci_resume,
566 	.freeze		= check_root_hub_suspended,
567 	.freeze_noirq	= check_root_hub_suspended,
568 	.thaw_noirq	= NULL,
569 	.thaw		= NULL,
570 	.poweroff	= hcd_pci_suspend,
571 	.poweroff_noirq	= hcd_pci_suspend_noirq,
572 	.restore_noirq	= hcd_pci_resume_noirq,
573 	.restore	= hcd_pci_restore,
574 	.runtime_suspend = hcd_pci_runtime_suspend,
575 	.runtime_resume	= hcd_pci_runtime_resume,
576 };
577 EXPORT_SYMBOL_GPL(usb_hcd_pci_pm_ops);
578 
579 #endif	/* CONFIG_PM_OPS */
580