xref: /openbmc/linux/drivers/usb/core/hcd-pci.c (revision 545e4006)
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 
77 	if (!dev->irq) {
78 		dev_err(&dev->dev,
79 			"Found HC with no IRQ.  Check BIOS/PCI %s setup!\n",
80 			pci_name(dev));
81 		retval = -ENODEV;
82 		goto err1;
83 	}
84 
85 	hcd = usb_create_hcd(driver, &dev->dev, pci_name(dev));
86 	if (!hcd) {
87 		retval = -ENOMEM;
88 		goto err1;
89 	}
90 
91 	if (driver->flags & HCD_MEMORY) {
92 		/* EHCI, OHCI */
93 		hcd->rsrc_start = pci_resource_start(dev, 0);
94 		hcd->rsrc_len = pci_resource_len(dev, 0);
95 		if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len,
96 				driver->description)) {
97 			dev_dbg(&dev->dev, "controller already in use\n");
98 			retval = -EBUSY;
99 			goto err2;
100 		}
101 		hcd->regs = ioremap_nocache(hcd->rsrc_start, hcd->rsrc_len);
102 		if (hcd->regs == NULL) {
103 			dev_dbg(&dev->dev, "error mapping memory\n");
104 			retval = -EFAULT;
105 			goto err3;
106 		}
107 
108 	} else {
109 		/* UHCI */
110 		int	region;
111 
112 		for (region = 0; region < PCI_ROM_RESOURCE; region++) {
113 			if (!(pci_resource_flags(dev, region) &
114 					IORESOURCE_IO))
115 				continue;
116 
117 			hcd->rsrc_start = pci_resource_start(dev, region);
118 			hcd->rsrc_len = pci_resource_len(dev, region);
119 			if (request_region(hcd->rsrc_start, hcd->rsrc_len,
120 					driver->description))
121 				break;
122 		}
123 		if (region == PCI_ROM_RESOURCE) {
124 			dev_dbg(&dev->dev, "no i/o regions available\n");
125 			retval = -EBUSY;
126 			goto err1;
127 		}
128 	}
129 
130 	pci_set_master(dev);
131 
132 	retval = usb_add_hcd(hcd, dev->irq, IRQF_DISABLED | IRQF_SHARED);
133 	if (retval != 0)
134 		goto err4;
135 	return retval;
136 
137  err4:
138 	if (driver->flags & HCD_MEMORY) {
139 		iounmap(hcd->regs);
140  err3:
141 		release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
142 	} else
143 		release_region(hcd->rsrc_start, hcd->rsrc_len);
144  err2:
145 	usb_put_hcd(hcd);
146  err1:
147 	pci_disable_device(dev);
148 	dev_err(&dev->dev, "init %s fail, %d\n", pci_name(dev), retval);
149 	return retval;
150 }
151 EXPORT_SYMBOL_GPL(usb_hcd_pci_probe);
152 
153 
154 /* may be called without controller electrically present */
155 /* may be called with controller, bus, and devices active */
156 
157 /**
158  * usb_hcd_pci_remove - shutdown processing for PCI-based HCDs
159  * @dev: USB Host Controller being removed
160  * Context: !in_interrupt()
161  *
162  * Reverses the effect of usb_hcd_pci_probe(), first invoking
163  * the HCD's stop() method.  It is always called from a thread
164  * context, normally "rmmod", "apmd", or something similar.
165  *
166  * Store this function in the HCD's struct pci_driver as remove().
167  */
168 void usb_hcd_pci_remove(struct pci_dev *dev)
169 {
170 	struct usb_hcd		*hcd;
171 
172 	hcd = pci_get_drvdata(dev);
173 	if (!hcd)
174 		return;
175 
176 	usb_remove_hcd(hcd);
177 	if (hcd->driver->flags & HCD_MEMORY) {
178 		iounmap(hcd->regs);
179 		release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
180 	} else {
181 		release_region(hcd->rsrc_start, hcd->rsrc_len);
182 	}
183 	usb_put_hcd(hcd);
184 	pci_disable_device(dev);
185 }
186 EXPORT_SYMBOL_GPL(usb_hcd_pci_remove);
187 
188 
189 #ifdef	CONFIG_PM
190 
191 /**
192  * usb_hcd_pci_suspend - power management suspend of a PCI-based HCD
193  * @dev: USB Host Controller being suspended
194  * @message: semantics in flux
195  *
196  * Store this function in the HCD's struct pci_driver as suspend().
197  */
198 int usb_hcd_pci_suspend(struct pci_dev *dev, pm_message_t message)
199 {
200 	struct usb_hcd		*hcd;
201 	int			retval = 0;
202 	int			has_pci_pm;
203 
204 	hcd = pci_get_drvdata(dev);
205 
206 	/* Root hub suspend should have stopped all downstream traffic,
207 	 * and all bus master traffic.  And done so for both the interface
208 	 * and the stub usb_device (which we check here).  But maybe it
209 	 * didn't; writing sysfs power/state files ignores such rules...
210 	 *
211 	 * We must ignore the FREEZE vs SUSPEND distinction here, because
212 	 * otherwise the swsusp will save (and restore) garbage state.
213 	 */
214 	if (!(hcd->state == HC_STATE_SUSPENDED ||
215 			hcd->state == HC_STATE_HALT))
216 		return -EBUSY;
217 
218 	if (hcd->driver->pci_suspend) {
219 		retval = hcd->driver->pci_suspend(hcd, message);
220 		suspend_report_result(hcd->driver->pci_suspend, retval);
221 		if (retval)
222 			goto done;
223 	}
224 	synchronize_irq(dev->irq);
225 
226 	/* FIXME until the generic PM interfaces change a lot more, this
227 	 * can't use PCI D1 and D2 states.  For example, the confusion
228 	 * between messages and states will need to vanish, and messages
229 	 * will need to provide a target system state again.
230 	 *
231 	 * It'll be important to learn characteristics of the target state,
232 	 * especially on embedded hardware where the HCD will often be in
233 	 * charge of an external VBUS power supply and one or more clocks.
234 	 * Some target system states will leave them active; others won't.
235 	 * (With PCI, that's often handled by platform BIOS code.)
236 	 */
237 
238 	/* even when the PCI layer rejects some of the PCI calls
239 	 * below, HCs can try global suspend and reduce DMA traffic.
240 	 * PM-sensitive HCDs may already have done this.
241 	 */
242 	has_pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM);
243 
244 	/* Downstream ports from this root hub should already be quiesced, so
245 	 * there will be no DMA activity.  Now we can shut down the upstream
246 	 * link (except maybe for PME# resume signaling) and enter some PCI
247 	 * low power state, if the hardware allows.
248 	 */
249 	if (hcd->state == HC_STATE_SUSPENDED) {
250 
251 		/* no DMA or IRQs except when HC is active */
252 		if (dev->current_state == PCI_D0) {
253 			pci_save_state(dev);
254 			pci_disable_device(dev);
255 		}
256 
257 		if (message.event == PM_EVENT_FREEZE ||
258 				message.event == PM_EVENT_PRETHAW) {
259 			dev_dbg(hcd->self.controller, "--> no state change\n");
260 			goto done;
261 		}
262 
263 		if (!has_pci_pm) {
264 			dev_dbg(hcd->self.controller, "--> PCI D0/legacy\n");
265 			goto done;
266 		}
267 
268 		/* NOTE:  dev->current_state becomes nonzero only here, and
269 		 * only for devices that support PCI PM.  Also, exiting
270 		 * PCI_D3 (but not PCI_D1 or PCI_D2) is allowed to reset
271 		 * some device state (e.g. as part of clock reinit).
272 		 */
273 		retval = pci_set_power_state(dev, PCI_D3hot);
274 		suspend_report_result(pci_set_power_state, retval);
275 		if (retval == 0) {
276 			int wake = device_can_wakeup(&hcd->self.root_hub->dev);
277 
278 			wake = wake && device_may_wakeup(hcd->self.controller);
279 
280 			dev_dbg(hcd->self.controller, "--> PCI D3%s\n",
281 					wake ? "/wakeup" : "");
282 
283 			/* Ignore these return values.  We rely on pci code to
284 			 * reject requests the hardware can't implement, rather
285 			 * than coding the same thing.
286 			 */
287 			(void) pci_enable_wake(dev, PCI_D3hot, wake);
288 			(void) pci_enable_wake(dev, PCI_D3cold, wake);
289 		} else {
290 			dev_dbg(&dev->dev, "PCI D3 suspend fail, %d\n",
291 					retval);
292 			(void) usb_hcd_pci_resume(dev);
293 		}
294 
295 	} else if (hcd->state != HC_STATE_HALT) {
296 		dev_dbg(hcd->self.controller, "hcd state %d; not suspended\n",
297 			hcd->state);
298 		WARN_ON(1);
299 		retval = -EINVAL;
300 	}
301 
302 done:
303 	if (retval == 0) {
304 #ifdef CONFIG_PPC_PMAC
305 		/* Disable ASIC clocks for USB */
306 		if (machine_is(powermac)) {
307 			struct device_node	*of_node;
308 
309 			of_node = pci_device_to_OF_node(dev);
310 			if (of_node)
311 				pmac_call_feature(PMAC_FTR_USB_ENABLE,
312 							of_node, 0, 0);
313 		}
314 #endif
315 	}
316 
317 	return retval;
318 }
319 EXPORT_SYMBOL_GPL(usb_hcd_pci_suspend);
320 
321 /**
322  * usb_hcd_pci_resume - power management resume of a PCI-based HCD
323  * @dev: USB Host Controller being resumed
324  *
325  * Store this function in the HCD's struct pci_driver as resume().
326  */
327 int usb_hcd_pci_resume(struct pci_dev *dev)
328 {
329 	struct usb_hcd		*hcd;
330 	int			retval;
331 
332 	hcd = pci_get_drvdata(dev);
333 	if (hcd->state != HC_STATE_SUSPENDED) {
334 		dev_dbg(hcd->self.controller,
335 				"can't resume, not suspended!\n");
336 		return 0;
337 	}
338 
339 #ifdef CONFIG_PPC_PMAC
340 	/* Reenable ASIC clocks for USB */
341 	if (machine_is(powermac)) {
342 		struct device_node *of_node;
343 
344 		of_node = pci_device_to_OF_node(dev);
345 		if (of_node)
346 			pmac_call_feature(PMAC_FTR_USB_ENABLE,
347 						of_node, 0, 1);
348 	}
349 #endif
350 
351 	/* NOTE:  chip docs cover clean "real suspend" cases (what Linux
352 	 * calls "standby", "suspend to RAM", and so on).  There are also
353 	 * dirty cases when swsusp fakes a suspend in "shutdown" mode.
354 	 */
355 	if (dev->current_state != PCI_D0) {
356 #ifdef	DEBUG
357 		int	pci_pm;
358 		u16	pmcr;
359 
360 		pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM);
361 		pci_read_config_word(dev, pci_pm + PCI_PM_CTRL, &pmcr);
362 		pmcr &= PCI_PM_CTRL_STATE_MASK;
363 		if (pmcr) {
364 			/* Clean case:  power to USB and to HC registers was
365 			 * maintained; remote wakeup is easy.
366 			 */
367 			dev_dbg(hcd->self.controller, "resume from PCI D%d\n",
368 					pmcr);
369 		} else {
370 			/* Clean:  HC lost Vcc power, D0 uninitialized
371 			 *   + Vaux may have preserved port and transceiver
372 			 *     state ... for remote wakeup from D3cold
373 			 *   + or not; HCD must reinit + re-enumerate
374 			 *
375 			 * Dirty: D0 semi-initialized cases with swsusp
376 			 *   + after BIOS init
377 			 *   + after Linux init (HCD statically linked)
378 			 */
379 			dev_dbg(hcd->self.controller,
380 				"PCI D0, from previous PCI D%d\n",
381 				dev->current_state);
382 		}
383 #endif
384 		/* yes, ignore these results too... */
385 		(void) pci_enable_wake(dev, dev->current_state, 0);
386 		(void) pci_enable_wake(dev, PCI_D3cold, 0);
387 	} else {
388 		/* Same basic cases: clean (powered/not), dirty */
389 		dev_dbg(hcd->self.controller, "PCI legacy resume\n");
390 	}
391 
392 	/* NOTE:  the PCI API itself is asymmetric here.  We don't need to
393 	 * pci_set_power_state(PCI_D0) since that's part of re-enabling;
394 	 * but that won't re-enable bus mastering.  Yet pci_disable_device()
395 	 * explicitly disables bus mastering...
396 	 */
397 	retval = pci_enable_device(dev);
398 	if (retval < 0) {
399 		dev_err(hcd->self.controller,
400 			"can't re-enable after resume, %d!\n", retval);
401 		return retval;
402 	}
403 	pci_set_master(dev);
404 	pci_restore_state(dev);
405 
406 	clear_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
407 
408 	if (hcd->driver->pci_resume) {
409 		retval = hcd->driver->pci_resume(hcd);
410 		if (retval) {
411 			dev_err(hcd->self.controller,
412 				"PCI post-resume error %d!\n", retval);
413 			usb_hc_died(hcd);
414 		}
415 	}
416 
417 	return retval;
418 }
419 EXPORT_SYMBOL_GPL(usb_hcd_pci_resume);
420 
421 #endif	/* CONFIG_PM */
422 
423 /**
424  * usb_hcd_pci_shutdown - shutdown host controller
425  * @dev: USB Host Controller being shutdown
426  */
427 void usb_hcd_pci_shutdown(struct pci_dev *dev)
428 {
429 	struct usb_hcd		*hcd;
430 
431 	hcd = pci_get_drvdata(dev);
432 	if (!hcd)
433 		return;
434 
435 	if (hcd->driver->shutdown)
436 		hcd->driver->shutdown(hcd);
437 }
438 EXPORT_SYMBOL_GPL(usb_hcd_pci_shutdown);
439 
440