xref: /linux/drivers/usb/core/hcd-pci.c (revision 54a8a2220c936a47840c9a3d74910c5a56fae2ed)
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/config.h>
20 
21 #ifdef CONFIG_USB_DEBUG
22 	#define DEBUG
23 #else
24 	#undef DEBUG
25 #endif
26 
27 #include <linux/kernel.h>
28 #include <linux/module.h>
29 #include <linux/pci.h>
30 #include <asm/io.h>
31 #include <asm/irq.h>
32 #include <linux/usb.h>
33 #include "hcd.h"
34 
35 
36 /* PCI-based HCs are common, but plenty of non-PCI HCs are used too */
37 
38 
39 /*-------------------------------------------------------------------------*/
40 
41 /* configure so an HC device and id are always provided */
42 /* always called with process context; sleeping is OK */
43 
44 /**
45  * usb_hcd_pci_probe - initialize PCI-based HCDs
46  * @dev: USB Host Controller being probed
47  * @id: pci hotplug id connecting controller to HCD framework
48  * Context: !in_interrupt()
49  *
50  * Allocates basic PCI resources for this USB host controller, and
51  * then invokes the start() method for the HCD associated with it
52  * through the hotplug entry's driver_data.
53  *
54  * Store this function in the HCD's struct pci_driver as probe().
55  */
56 int usb_hcd_pci_probe (struct pci_dev *dev, const struct pci_device_id *id)
57 {
58 	struct hc_driver	*driver;
59 	struct usb_hcd		*hcd;
60 	int			retval;
61 
62 	if (usb_disabled())
63 		return -ENODEV;
64 
65 	if (!id || !(driver = (struct hc_driver *) id->driver_data))
66 		return -EINVAL;
67 
68 	if (pci_enable_device (dev) < 0)
69 		return -ENODEV;
70 	dev->current_state = PCI_D0;
71 	dev->dev.power.power_state = PMSG_ON;
72 
73         if (!dev->irq) {
74         	dev_err (&dev->dev,
75 			"Found HC with no IRQ.  Check BIOS/PCI %s setup!\n",
76 			pci_name(dev));
77    	        retval = -ENODEV;
78 		goto err1;
79         }
80 
81 	hcd = usb_create_hcd (driver, &dev->dev, pci_name(dev));
82 	if (!hcd) {
83 		retval = -ENOMEM;
84 		goto err1;
85 	}
86 
87 	if (driver->flags & HCD_MEMORY) {	// EHCI, OHCI
88 		hcd->rsrc_start = pci_resource_start (dev, 0);
89 		hcd->rsrc_len = pci_resource_len (dev, 0);
90 		if (!request_mem_region (hcd->rsrc_start, hcd->rsrc_len,
91 				driver->description)) {
92 			dev_dbg (&dev->dev, "controller already in use\n");
93 			retval = -EBUSY;
94 			goto err2;
95 		}
96 		hcd->regs = ioremap_nocache (hcd->rsrc_start, hcd->rsrc_len);
97 		if (hcd->regs == NULL) {
98 			dev_dbg (&dev->dev, "error mapping memory\n");
99 			retval = -EFAULT;
100 			goto err3;
101 		}
102 
103 	} else { 				// UHCI
104 		int	region;
105 
106 		for (region = 0; region < PCI_ROM_RESOURCE; region++) {
107 			if (!(pci_resource_flags (dev, region) &
108 					IORESOURCE_IO))
109 				continue;
110 
111 			hcd->rsrc_start = pci_resource_start (dev, region);
112 			hcd->rsrc_len = pci_resource_len (dev, region);
113 			if (request_region (hcd->rsrc_start, hcd->rsrc_len,
114 					driver->description))
115 				break;
116 		}
117 		if (region == PCI_ROM_RESOURCE) {
118 			dev_dbg (&dev->dev, "no i/o regions available\n");
119 			retval = -EBUSY;
120 			goto err1;
121 		}
122 	}
123 
124 	pci_set_master (dev);
125 
126 	retval = usb_add_hcd (hcd, dev->irq, SA_SHIRQ);
127 	if (retval != 0)
128 		goto err4;
129 	return retval;
130 
131  err4:
132 	if (driver->flags & HCD_MEMORY) {
133 		iounmap (hcd->regs);
134  err3:
135 		release_mem_region (hcd->rsrc_start, hcd->rsrc_len);
136 	} else
137 		release_region (hcd->rsrc_start, hcd->rsrc_len);
138  err2:
139 	usb_put_hcd (hcd);
140  err1:
141 	pci_disable_device (dev);
142 	dev_err (&dev->dev, "init %s fail, %d\n", pci_name(dev), retval);
143 	return retval;
144 }
145 EXPORT_SYMBOL (usb_hcd_pci_probe);
146 
147 
148 /* may be called without controller electrically present */
149 /* may be called with controller, bus, and devices active */
150 
151 /**
152  * usb_hcd_pci_remove - shutdown processing for PCI-based HCDs
153  * @dev: USB Host Controller being removed
154  * Context: !in_interrupt()
155  *
156  * Reverses the effect of usb_hcd_pci_probe(), first invoking
157  * the HCD's stop() method.  It is always called from a thread
158  * context, normally "rmmod", "apmd", or something similar.
159  *
160  * Store this function in the HCD's struct pci_driver as remove().
161  */
162 void usb_hcd_pci_remove (struct pci_dev *dev)
163 {
164 	struct usb_hcd		*hcd;
165 
166 	hcd = pci_get_drvdata(dev);
167 	if (!hcd)
168 		return;
169 
170 	usb_remove_hcd (hcd);
171 	if (hcd->driver->flags & HCD_MEMORY) {
172 		iounmap (hcd->regs);
173 		release_mem_region (hcd->rsrc_start, hcd->rsrc_len);
174 	} else {
175 		release_region (hcd->rsrc_start, hcd->rsrc_len);
176 	}
177 	usb_put_hcd (hcd);
178 	pci_disable_device(dev);
179 }
180 EXPORT_SYMBOL (usb_hcd_pci_remove);
181 
182 
183 #ifdef	CONFIG_PM
184 
185 /**
186  * usb_hcd_pci_suspend - power management suspend of a PCI-based HCD
187  * @dev: USB Host Controller being suspended
188  * @message: semantics in flux
189  *
190  * Store this function in the HCD's struct pci_driver as suspend().
191  */
192 int usb_hcd_pci_suspend (struct pci_dev *dev, pm_message_t message)
193 {
194 	struct usb_hcd		*hcd;
195 	int			retval = 0;
196 	int			has_pci_pm;
197 
198 	hcd = pci_get_drvdata(dev);
199 
200 	/* FIXME until the generic PM interfaces change a lot more, this
201 	 * can't use PCI D1 and D2 states.  For example, the confusion
202 	 * between messages and states will need to vanish, and messages
203 	 * will need to provide a target system state again.
204 	 *
205 	 * It'll be important to learn characteristics of the target state,
206 	 * especially on embedded hardware where the HCD will often be in
207 	 * charge of an external VBUS power supply and one or more clocks.
208 	 * Some target system states will leave them active; others won't.
209 	 * (With PCI, that's often handled by platform BIOS code.)
210 	 */
211 
212 	/* even when the PCI layer rejects some of the PCI calls
213 	 * below, HCs can try global suspend and reduce DMA traffic.
214 	 * PM-sensitive HCDs may already have done this.
215 	 */
216 	has_pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM);
217 
218 	switch (hcd->state) {
219 
220 	/* entry if root hub wasn't yet suspended ... from sysfs,
221 	 * without autosuspend, or if USB_SUSPEND isn't configured.
222 	 */
223 	case HC_STATE_RUNNING:
224 		hcd->state = HC_STATE_QUIESCING;
225 		retval = hcd->driver->suspend (hcd, message);
226 		if (retval) {
227 			dev_dbg (hcd->self.controller,
228 					"suspend fail, retval %d\n",
229 					retval);
230 			break;
231 		}
232 		hcd->state = HC_STATE_SUSPENDED;
233 		/* FALLTHROUGH */
234 
235 	/* entry with CONFIG_USB_SUSPEND, or hcds that autosuspend: the
236 	 * controller and/or root hub will already have been suspended,
237 	 * but it won't be ready for a PCI resume call.
238 	 *
239 	 * FIXME only CONFIG_USB_SUSPEND guarantees hub_suspend() will
240 	 * have been called, otherwise root hub timers still run ...
241 	 */
242 	case HC_STATE_SUSPENDED:
243 		/* no DMA or IRQs except when HC is active */
244 		if (dev->current_state == PCI_D0) {
245 			pci_save_state (dev);
246 			pci_disable_device (dev);
247 		}
248 
249 		if (!has_pci_pm) {
250 			dev_dbg (hcd->self.controller, "--> PCI D0/legacy\n");
251 			break;
252 		}
253 
254 		/* NOTE:  dev->current_state becomes nonzero only here, and
255 		 * only for devices that support PCI PM.  Also, exiting
256 		 * PCI_D3 (but not PCI_D1 or PCI_D2) is allowed to reset
257 		 * some device state (e.g. as part of clock reinit).
258 		 */
259 		retval = pci_set_power_state (dev, PCI_D3hot);
260 		if (retval == 0) {
261 			dev_dbg (hcd->self.controller, "--> PCI D3\n");
262 			retval = pci_enable_wake (dev, PCI_D3hot, hcd->remote_wakeup);
263 			if (retval)
264 				break;
265 			retval = pci_enable_wake (dev, PCI_D3cold, hcd->remote_wakeup);
266 		} else if (retval < 0) {
267 			dev_dbg (&dev->dev, "PCI D3 suspend fail, %d\n",
268 					retval);
269 			(void) usb_hcd_pci_resume (dev);
270 			break;
271 		}
272 		break;
273 	default:
274 		dev_dbg (hcd->self.controller, "hcd state %d; not suspended\n",
275 			hcd->state);
276 		WARN_ON(1);
277 		retval = -EINVAL;
278 		break;
279 	}
280 
281 	/* update power_state **ONLY** to make sysfs happier */
282 	if (retval == 0)
283 		dev->dev.power.power_state = message;
284 	return retval;
285 }
286 EXPORT_SYMBOL (usb_hcd_pci_suspend);
287 
288 /**
289  * usb_hcd_pci_resume - power management resume of a PCI-based HCD
290  * @dev: USB Host Controller being resumed
291  *
292  * Store this function in the HCD's struct pci_driver as resume().
293  */
294 int usb_hcd_pci_resume (struct pci_dev *dev)
295 {
296 	struct usb_hcd		*hcd;
297 	int			retval;
298 
299 	hcd = pci_get_drvdata(dev);
300 	if (hcd->state != HC_STATE_SUSPENDED) {
301 		dev_dbg (hcd->self.controller,
302 				"can't resume, not suspended!\n");
303 		return 0;
304 	}
305 
306 	/* NOTE:  chip docs cover clean "real suspend" cases (what Linux
307 	 * calls "standby", "suspend to RAM", and so on).  There are also
308 	 * dirty cases when swsusp fakes a suspend in "shutdown" mode.
309 	 */
310 	if (dev->current_state != PCI_D0) {
311 #ifdef	DEBUG
312 		int	pci_pm;
313 		u16	pmcr;
314 
315 		pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM);
316 		pci_read_config_word(dev, pci_pm + PCI_PM_CTRL, &pmcr);
317 		pmcr &= PCI_PM_CTRL_STATE_MASK;
318 		if (pmcr) {
319 			/* Clean case:  power to USB and to HC registers was
320 			 * maintained; remote wakeup is easy.
321 			 */
322 			dev_dbg(hcd->self.controller, "resume from PCI D%d\n",
323 					pmcr);
324 		} else {
325 			/* Clean:  HC lost Vcc power, D0 uninitialized
326 			 *   + Vaux may have preserved port and transceiver
327 			 *     state ... for remote wakeup from D3cold
328 			 *   + or not; HCD must reinit + re-enumerate
329 			 *
330 			 * Dirty: D0 semi-initialized cases with swsusp
331 			 *   + after BIOS init
332 			 *   + after Linux init (HCD statically linked)
333 			 */
334 			dev_dbg(hcd->self.controller,
335 				"PCI D0, from previous PCI D%d\n",
336 				dev->current_state);
337 		}
338 #endif
339 		retval = pci_enable_wake (dev, dev->current_state, 0);
340 		if (retval) {
341 			dev_err(hcd->self.controller,
342 				"can't enable_wake to %d, %d!\n",
343 				dev->current_state, retval);
344 			return retval;
345 		}
346 		retval = pci_enable_wake (dev, PCI_D3cold, 0);
347 		if (retval) {
348 			dev_err(hcd->self.controller,
349 				"can't enable_wake to %d, %d!\n",
350 				PCI_D3cold, retval);
351 			return retval;
352 		}
353 	} else {
354 		/* Same basic cases: clean (powered/not), dirty */
355 		dev_dbg(hcd->self.controller, "PCI legacy resume\n");
356 	}
357 
358 	/* NOTE:  the PCI API itself is asymmetric here.  We don't need to
359 	 * pci_set_power_state(PCI_D0) since that's part of re-enabling;
360 	 * but that won't re-enable bus mastering.  Yet pci_disable_device()
361 	 * explicitly disables bus mastering...
362 	 */
363 	retval = pci_enable_device (dev);
364 	if (retval < 0) {
365 		dev_err (hcd->self.controller,
366 			"can't re-enable after resume, %d!\n", retval);
367 		return retval;
368 	}
369 	pci_set_master (dev);
370 	pci_restore_state (dev);
371 
372 	dev->dev.power.power_state = PMSG_ON;
373 
374 	hcd->state = HC_STATE_RESUMING;
375 	hcd->saw_irq = 0;
376 
377 	retval = hcd->driver->resume (hcd);
378 	if (!HC_IS_RUNNING (hcd->state)) {
379 		dev_dbg (hcd->self.controller,
380 				"resume fail, retval %d\n", retval);
381 		usb_hc_died (hcd);
382 	}
383 
384 	retval = pci_enable_device(dev);
385 	return retval;
386 }
387 EXPORT_SYMBOL (usb_hcd_pci_resume);
388 
389 #endif	/* CONFIG_PM */
390 
391 
392