xref: /openbmc/linux/drivers/usb/core/hcd-pci.c (revision a1e58bbd)
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/usb.h>
23 
24 #include <asm/io.h>
25 #include <asm/irq.h>
26 
27 #ifdef CONFIG_PPC_PMAC
28 #include <asm/machdep.h>
29 #include <asm/pmac_feature.h>
30 #include <asm/pci-bridge.h>
31 #include <asm/prom.h>
32 #endif
33 
34 #include "usb.h"
35 #include "hcd.h"
36 
37 
38 /* PCI-based HCs are common, but plenty of non-PCI HCs are used too */
39 
40 
41 /*-------------------------------------------------------------------------*/
42 
43 /* configure so an HC device and id are always provided */
44 /* always called with process context; sleeping is OK */
45 
46 /**
47  * usb_hcd_pci_probe - initialize PCI-based HCDs
48  * @dev: USB Host Controller being probed
49  * @id: pci hotplug id connecting controller to HCD framework
50  * Context: !in_interrupt()
51  *
52  * Allocates basic PCI resources for this USB host controller, and
53  * then invokes the start() method for the HCD associated with it
54  * through the hotplug entry's driver_data.
55  *
56  * Store this function in the HCD's struct pci_driver as probe().
57  */
58 int usb_hcd_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
59 {
60 	struct hc_driver	*driver;
61 	struct usb_hcd		*hcd;
62 	int			retval;
63 
64 	if (usb_disabled())
65 		return -ENODEV;
66 
67 	if (!id)
68 		return -EINVAL;
69 	driver = (struct hc_driver *)id->driver_data;
70 	if (!driver)
71 		return -EINVAL;
72 
73 	if (pci_enable_device(dev) < 0)
74 		return -ENODEV;
75 	dev->current_state = PCI_D0;
76 	dev->dev.power.power_state = PMSG_ON;
77 
78 	if (!dev->irq) {
79 		dev_err(&dev->dev,
80 			"Found HC with no IRQ.  Check BIOS/PCI %s setup!\n",
81 			pci_name(dev));
82 		retval = -ENODEV;
83 		goto err1;
84 	}
85 
86 	hcd = usb_create_hcd(driver, &dev->dev, pci_name(dev));
87 	if (!hcd) {
88 		retval = -ENOMEM;
89 		goto err1;
90 	}
91 
92 	if (driver->flags & HCD_MEMORY) {
93 		/* EHCI, OHCI */
94 		hcd->rsrc_start = pci_resource_start(dev, 0);
95 		hcd->rsrc_len = pci_resource_len(dev, 0);
96 		if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len,
97 				driver->description)) {
98 			dev_dbg(&dev->dev, "controller already in use\n");
99 			retval = -EBUSY;
100 			goto err2;
101 		}
102 		hcd->regs = ioremap_nocache(hcd->rsrc_start, hcd->rsrc_len);
103 		if (hcd->regs == NULL) {
104 			dev_dbg(&dev->dev, "error mapping memory\n");
105 			retval = -EFAULT;
106 			goto err3;
107 		}
108 
109 	} else {
110 		/* UHCI */
111 		int	region;
112 
113 		for (region = 0; region < PCI_ROM_RESOURCE; region++) {
114 			if (!(pci_resource_flags(dev, region) &
115 					IORESOURCE_IO))
116 				continue;
117 
118 			hcd->rsrc_start = pci_resource_start(dev, region);
119 			hcd->rsrc_len = pci_resource_len(dev, region);
120 			if (request_region(hcd->rsrc_start, hcd->rsrc_len,
121 					driver->description))
122 				break;
123 		}
124 		if (region == PCI_ROM_RESOURCE) {
125 			dev_dbg(&dev->dev, "no i/o regions available\n");
126 			retval = -EBUSY;
127 			goto err1;
128 		}
129 	}
130 
131 	pci_set_master(dev);
132 
133 	retval = usb_add_hcd(hcd, dev->irq, IRQF_DISABLED | IRQF_SHARED);
134 	if (retval != 0)
135 		goto err4;
136 	return retval;
137 
138  err4:
139 	if (driver->flags & HCD_MEMORY) {
140 		iounmap(hcd->regs);
141  err3:
142 		release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
143 	} else
144 		release_region(hcd->rsrc_start, hcd->rsrc_len);
145  err2:
146 	usb_put_hcd(hcd);
147  err1:
148 	pci_disable_device(dev);
149 	dev_err(&dev->dev, "init %s fail, %d\n", pci_name(dev), retval);
150 	return retval;
151 }
152 EXPORT_SYMBOL_GPL(usb_hcd_pci_probe);
153 
154 
155 /* may be called without controller electrically present */
156 /* may be called with controller, bus, and devices active */
157 
158 /**
159  * usb_hcd_pci_remove - shutdown processing for PCI-based HCDs
160  * @dev: USB Host Controller being removed
161  * Context: !in_interrupt()
162  *
163  * Reverses the effect of usb_hcd_pci_probe(), first invoking
164  * the HCD's stop() method.  It is always called from a thread
165  * context, normally "rmmod", "apmd", or something similar.
166  *
167  * Store this function in the HCD's struct pci_driver as remove().
168  */
169 void usb_hcd_pci_remove(struct pci_dev *dev)
170 {
171 	struct usb_hcd		*hcd;
172 
173 	hcd = pci_get_drvdata(dev);
174 	if (!hcd)
175 		return;
176 
177 	usb_remove_hcd(hcd);
178 	if (hcd->driver->flags & HCD_MEMORY) {
179 		iounmap(hcd->regs);
180 		release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
181 	} else {
182 		release_region(hcd->rsrc_start, hcd->rsrc_len);
183 	}
184 	usb_put_hcd(hcd);
185 	pci_disable_device(dev);
186 }
187 EXPORT_SYMBOL_GPL(usb_hcd_pci_remove);
188 
189 
190 #ifdef	CONFIG_PM
191 
192 /**
193  * usb_hcd_pci_suspend - power management suspend of a PCI-based HCD
194  * @dev: USB Host Controller being suspended
195  * @message: semantics in flux
196  *
197  * Store this function in the HCD's struct pci_driver as suspend().
198  */
199 int usb_hcd_pci_suspend(struct pci_dev *dev, pm_message_t message)
200 {
201 	struct usb_hcd		*hcd;
202 	int			retval = 0;
203 	int			has_pci_pm;
204 
205 	hcd = pci_get_drvdata(dev);
206 
207 	/* Root hub suspend should have stopped all downstream traffic,
208 	 * and all bus master traffic.  And done so for both the interface
209 	 * and the stub usb_device (which we check here).  But maybe it
210 	 * didn't; writing sysfs power/state files ignores such rules...
211 	 *
212 	 * We must ignore the FREEZE vs SUSPEND distinction here, because
213 	 * otherwise the swsusp will save (and restore) garbage state.
214 	 */
215 	if (!(hcd->state == HC_STATE_SUSPENDED ||
216 			hcd->state == HC_STATE_HALT))
217 		return -EBUSY;
218 
219 	if (hcd->driver->suspend) {
220 		retval = hcd->driver->suspend(hcd, message);
221 		suspend_report_result(hcd->driver->suspend, retval);
222 		if (retval)
223 			goto done;
224 	}
225 	synchronize_irq(dev->irq);
226 
227 	/* FIXME until the generic PM interfaces change a lot more, this
228 	 * can't use PCI D1 and D2 states.  For example, the confusion
229 	 * between messages and states will need to vanish, and messages
230 	 * will need to provide a target system state again.
231 	 *
232 	 * It'll be important to learn characteristics of the target state,
233 	 * especially on embedded hardware where the HCD will often be in
234 	 * charge of an external VBUS power supply and one or more clocks.
235 	 * Some target system states will leave them active; others won't.
236 	 * (With PCI, that's often handled by platform BIOS code.)
237 	 */
238 
239 	/* even when the PCI layer rejects some of the PCI calls
240 	 * below, HCs can try global suspend and reduce DMA traffic.
241 	 * PM-sensitive HCDs may already have done this.
242 	 */
243 	has_pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM);
244 
245 	/* Downstream ports from this root hub should already be quiesced, so
246 	 * there will be no DMA activity.  Now we can shut down the upstream
247 	 * link (except maybe for PME# resume signaling) and enter some PCI
248 	 * low power state, if the hardware allows.
249 	 */
250 	if (hcd->state == HC_STATE_SUSPENDED) {
251 
252 		/* no DMA or IRQs except when HC is active */
253 		if (dev->current_state == PCI_D0) {
254 			pci_save_state(dev);
255 			pci_disable_device(dev);
256 		}
257 
258 		if (message.event == PM_EVENT_FREEZE ||
259 				message.event == PM_EVENT_PRETHAW) {
260 			dev_dbg(hcd->self.controller, "--> no state change\n");
261 			goto done;
262 		}
263 
264 		if (!has_pci_pm) {
265 			dev_dbg(hcd->self.controller, "--> PCI D0/legacy\n");
266 			goto done;
267 		}
268 
269 		/* NOTE:  dev->current_state becomes nonzero only here, and
270 		 * only for devices that support PCI PM.  Also, exiting
271 		 * PCI_D3 (but not PCI_D1 or PCI_D2) is allowed to reset
272 		 * some device state (e.g. as part of clock reinit).
273 		 */
274 		retval = pci_set_power_state(dev, PCI_D3hot);
275 		suspend_report_result(pci_set_power_state, retval);
276 		if (retval == 0) {
277 			int wake = device_can_wakeup(&hcd->self.root_hub->dev);
278 
279 			wake = wake && device_may_wakeup(hcd->self.controller);
280 
281 			dev_dbg(hcd->self.controller, "--> PCI D3%s\n",
282 					wake ? "/wakeup" : "");
283 
284 			/* Ignore these return values.  We rely on pci code to
285 			 * reject requests the hardware can't implement, rather
286 			 * than coding the same thing.
287 			 */
288 			(void) pci_enable_wake(dev, PCI_D3hot, wake);
289 			(void) pci_enable_wake(dev, PCI_D3cold, wake);
290 		} else {
291 			dev_dbg(&dev->dev, "PCI D3 suspend fail, %d\n",
292 					retval);
293 			(void) usb_hcd_pci_resume(dev);
294 		}
295 
296 	} else if (hcd->state != HC_STATE_HALT) {
297 		dev_dbg(hcd->self.controller, "hcd state %d; not suspended\n",
298 			hcd->state);
299 		WARN_ON(1);
300 		retval = -EINVAL;
301 	}
302 
303 done:
304 	if (retval == 0) {
305 		dev->dev.power.power_state = PMSG_SUSPEND;
306 
307 #ifdef CONFIG_PPC_PMAC
308 		/* Disable ASIC clocks for USB */
309 		if (machine_is(powermac)) {
310 			struct device_node	*of_node;
311 
312 			of_node = pci_device_to_OF_node(dev);
313 			if (of_node)
314 				pmac_call_feature(PMAC_FTR_USB_ENABLE,
315 							of_node, 0, 0);
316 		}
317 #endif
318 	}
319 
320 	return retval;
321 }
322 EXPORT_SYMBOL_GPL(usb_hcd_pci_suspend);
323 
324 /**
325  * usb_hcd_pci_resume - power management resume of a PCI-based HCD
326  * @dev: USB Host Controller being resumed
327  *
328  * Store this function in the HCD's struct pci_driver as resume().
329  */
330 int usb_hcd_pci_resume(struct pci_dev *dev)
331 {
332 	struct usb_hcd		*hcd;
333 	int			retval;
334 
335 	hcd = pci_get_drvdata(dev);
336 	if (hcd->state != HC_STATE_SUSPENDED) {
337 		dev_dbg(hcd->self.controller,
338 				"can't resume, not suspended!\n");
339 		return 0;
340 	}
341 
342 #ifdef CONFIG_PPC_PMAC
343 	/* Reenable ASIC clocks for USB */
344 	if (machine_is(powermac)) {
345 		struct device_node *of_node;
346 
347 		of_node = pci_device_to_OF_node(dev);
348 		if (of_node)
349 			pmac_call_feature(PMAC_FTR_USB_ENABLE,
350 						of_node, 0, 1);
351 	}
352 #endif
353 
354 	/* NOTE:  chip docs cover clean "real suspend" cases (what Linux
355 	 * calls "standby", "suspend to RAM", and so on).  There are also
356 	 * dirty cases when swsusp fakes a suspend in "shutdown" mode.
357 	 */
358 	if (dev->current_state != PCI_D0) {
359 #ifdef	DEBUG
360 		int	pci_pm;
361 		u16	pmcr;
362 
363 		pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM);
364 		pci_read_config_word(dev, pci_pm + PCI_PM_CTRL, &pmcr);
365 		pmcr &= PCI_PM_CTRL_STATE_MASK;
366 		if (pmcr) {
367 			/* Clean case:  power to USB and to HC registers was
368 			 * maintained; remote wakeup is easy.
369 			 */
370 			dev_dbg(hcd->self.controller, "resume from PCI D%d\n",
371 					pmcr);
372 		} else {
373 			/* Clean:  HC lost Vcc power, D0 uninitialized
374 			 *   + Vaux may have preserved port and transceiver
375 			 *     state ... for remote wakeup from D3cold
376 			 *   + or not; HCD must reinit + re-enumerate
377 			 *
378 			 * Dirty: D0 semi-initialized cases with swsusp
379 			 *   + after BIOS init
380 			 *   + after Linux init (HCD statically linked)
381 			 */
382 			dev_dbg(hcd->self.controller,
383 				"PCI D0, from previous PCI D%d\n",
384 				dev->current_state);
385 		}
386 #endif
387 		/* yes, ignore these results too... */
388 		(void) pci_enable_wake(dev, dev->current_state, 0);
389 		(void) pci_enable_wake(dev, PCI_D3cold, 0);
390 	} else {
391 		/* Same basic cases: clean (powered/not), dirty */
392 		dev_dbg(hcd->self.controller, "PCI legacy resume\n");
393 	}
394 
395 	/* NOTE:  the PCI API itself is asymmetric here.  We don't need to
396 	 * pci_set_power_state(PCI_D0) since that's part of re-enabling;
397 	 * but that won't re-enable bus mastering.  Yet pci_disable_device()
398 	 * explicitly disables bus mastering...
399 	 */
400 	retval = pci_enable_device(dev);
401 	if (retval < 0) {
402 		dev_err(hcd->self.controller,
403 			"can't re-enable after resume, %d!\n", retval);
404 		return retval;
405 	}
406 	pci_set_master(dev);
407 	pci_restore_state(dev);
408 
409 	dev->dev.power.power_state = PMSG_ON;
410 
411 	clear_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
412 
413 	if (hcd->driver->resume) {
414 		retval = hcd->driver->resume(hcd);
415 		if (retval) {
416 			dev_err(hcd->self.controller,
417 				"PCI post-resume error %d!\n", retval);
418 			usb_hc_died(hcd);
419 		}
420 	}
421 
422 	return retval;
423 }
424 EXPORT_SYMBOL_GPL(usb_hcd_pci_resume);
425 
426 #endif	/* CONFIG_PM */
427 
428 /**
429  * usb_hcd_pci_shutdown - shutdown host controller
430  * @dev: USB Host Controller being shutdown
431  */
432 void usb_hcd_pci_shutdown(struct pci_dev *dev)
433 {
434 	struct usb_hcd		*hcd;
435 
436 	hcd = pci_get_drvdata(dev);
437 	if (!hcd)
438 		return;
439 
440 	if (hcd->driver->shutdown)
441 		hcd->driver->shutdown(hcd);
442 }
443 EXPORT_SYMBOL_GPL(usb_hcd_pci_shutdown);
444 
445