aboutsummaryrefslogtreecommitdiff
path: root/drivers/usb/core/hcd-pci.c
blob: cbb451d227d215a372110204ab89950f93f66aed (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
/*
 * (C) Copyright David Brownell 2000-2002
 * 
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/config.h>

#ifdef CONFIG_USB_DEBUG
	#define DEBUG
#else
	#undef DEBUG
#endif

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <linux/usb.h>
#include "hcd.h"


/* PCI-based HCs are common, but plenty of non-PCI HCs are used too */


/*-------------------------------------------------------------------------*/

/* configure so an HC device and id are always provided */
/* always called with process context; sleeping is OK */

/**
 * usb_hcd_pci_probe - initialize PCI-based HCDs
 * @dev: USB Host Controller being probed
 * @id: pci hotplug id connecting controller to HCD framework
 * Context: !in_interrupt()
 *
 * Allocates basic PCI resources for this USB host controller, and
 * then invokes the start() method for the HCD associated with it
 * through the hotplug entry's driver_data.
 *
 * Store this function in the HCD's struct pci_driver as probe().
 */
int usb_hcd_pci_probe (struct pci_dev *dev, const struct pci_device_id *id)
{
	struct hc_driver	*driver;
	struct usb_hcd		*hcd;
	int			retval;

	if (usb_disabled())
		return -ENODEV;

	if (!id || !(driver = (struct hc_driver *) id->driver_data))
		return -EINVAL;

	if (pci_enable_device (dev) < 0)
		return -ENODEV;
	dev->current_state = PCI_D0;
	dev->dev.power.power_state = PMSG_ON;
	
        if (!dev->irq) {
        	dev_err (&dev->dev,
			"Found HC with no IRQ.  Check BIOS/PCI %s setup!\n",
			pci_name(dev));
   	        retval = -ENODEV;
		goto err1;
        }

	hcd = usb_create_hcd (driver, &dev->dev, pci_name(dev));
	if (!hcd) {
		retval = -ENOMEM;
		goto err1;
	}

	if (driver->flags & HCD_MEMORY) {	// EHCI, OHCI
		hcd->rsrc_start = pci_resource_start (dev, 0);
		hcd->rsrc_len = pci_resource_len (dev, 0);
		if (!request_mem_region (hcd->rsrc_start, hcd->rsrc_len,
				driver->description)) {
			dev_dbg (&dev->dev, "controller already in use\n");
			retval = -EBUSY;
			goto err2;
		}
		hcd->regs = ioremap_nocache (hcd->rsrc_start, hcd->rsrc_len);
		if (hcd->regs == NULL) {
			dev_dbg (&dev->dev, "error mapping memory\n");
			retval = -EFAULT;
			goto err3;
		}

	} else { 				// UHCI
		int	region;

		for (region = 0; region < PCI_ROM_RESOURCE; region++) {
			if (!(pci_resource_flags (dev, region) &
					IORESOURCE_IO))
				continue;

			hcd->rsrc_start = pci_resource_start (dev, region);
			hcd->rsrc_len = pci_resource_len (dev, region);
			if (request_region (hcd->rsrc_start, hcd->rsrc_len,
					driver->description))
				break;
		}
		if (region == PCI_ROM_RESOURCE) {
			dev_dbg (&dev->dev, "no i/o regions available\n");
			retval = -EBUSY;
			goto err1;
		}
	}

	pci_set_master (dev);

	retval = usb_add_hcd (hcd, dev->irq, SA_SHIRQ);
	if (retval != 0)
		goto err4;
	return retval;

 err4:
	if (driver->flags & HCD_MEMORY) {
		iounmap (hcd->regs);
 err3:
		release_mem_region (hcd->rsrc_start, hcd->rsrc_len);
	} else
		release_region (hcd->rsrc_start, hcd->rsrc_len);
 err2:
	usb_put_hcd (hcd);
 err1:
	pci_disable_device (dev);
	dev_err (&dev->dev, "init %s fail, %d\n", pci_name(dev), retval);
	return retval;
} 
EXPORT_SYMBOL (usb_hcd_pci_probe);


/* may be called without controller electrically present */
/* may be called with controller, bus, and devices active */

/**
 * usb_hcd_pci_remove - shutdown processing for PCI-based HCDs
 * @dev: USB Host Controller being removed
 * Context: !in_interrupt()
 *
 * Reverses the effect of usb_hcd_pci_probe(), first invoking
 * the HCD's stop() method.  It is always called from a thread
 * context, normally "rmmod", "apmd", or something similar.
 *
 * Store this function in the HCD's struct pci_driver as remove().
 */
void usb_hcd_pci_remove (struct pci_dev *dev)
{
	struct usb_hcd		*hcd;

	hcd = pci_get_drvdata(dev);
	if (!hcd)
		return;

	usb_remove_hcd (hcd);
	if (hcd->driver->flags & HCD_MEMORY) {
		iounmap (hcd->regs);
		release_mem_region (hcd->rsrc_start, hcd->rsrc_len);
	} else {
		release_region (hcd->rsrc_start, hcd->rsrc_len);
	}
	usb_put_hcd (hcd);
	pci_disable_device(dev);
}
EXPORT_SYMBOL (usb_hcd_pci_remove);


#ifdef	CONFIG_PM

/**
 * usb_hcd_pci_suspend - power management suspend of a PCI-based HCD
 * @dev: USB Host Controller being suspended
 * @message: semantics in flux
 *
 * Store this function in the HCD's struct pci_driver as suspend().
 */
int usb_hcd_pci_suspend (struct pci_dev *dev, pm_message_t message)
{
	struct usb_hcd		*hcd;
	int			retval = 0;
	int			has_pci_pm;

	hcd = pci_get_drvdata(dev);

	/* FIXME until the generic PM interfaces change a lot more, this
	 * can't use PCI D1 and D2 states.  For example, the confusion
	 * between messages and states will need to vanish, and messages
	 * will need to provide a target system state again.
	 *
	 * It'll be important to learn characteristics of the target state,
	 * especially on embedded hardware where the HCD will often be in
	 * charge of an external VBUS power supply and one or more clocks.
	 * Some target system states will leave them active; others won't.
	 * (With PCI, that's often handled by platform BIOS code.)
	 */

	/* even when the PCI layer rejects some of the PCI calls
	 * below, HCs can try global suspend and reduce DMA traffic.
	 * PM-sensitive HCDs may already have done this.
	 */
	has_pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM);

	switch (hcd->state) {

	/* entry if root hub wasn't yet suspended ... from sysfs,
	 * without autosuspend, or if USB_SUSPEND isn't configured.
	 */
	case HC_STATE_RUNNING:
		hcd->state = HC_STATE_QUIESCING;
		retval = hcd->driver->suspend (hcd, message);
		if (retval) {
			dev_dbg (hcd->self.controller, 
					"suspend fail, retval %d\n",
					retval);
			break;
		}
		hcd->state = HC_STATE_SUSPENDED;
		/* FALLTHROUGH */

	/* entry with CONFIG_USB_SUSPEND, or hcds that autosuspend: the
	 * controller and/or root hub will already have been suspended,
	 * but it won't be ready for a PCI resume call.
	 *
	 * FIXME only CONFIG_USB_SUSPEND guarantees hub_suspend() will
	 * have been called, otherwise root hub timers still run ...
	 */
	case HC_STATE_SUSPENDED:
		/* no DMA or IRQs except when HC is active */
		if (dev->current_state == PCI_D0) {
			free_irq (hcd->irq, hcd);
			pci_save_state (dev);
			pci_disable_device (dev);
		}

		if (!has_pci_pm) {
			dev_dbg (hcd->self.controller, "--> PCI D0/legacy\n");
			break;
		}

		/* NOTE:  dev->current_state becomes nonzero only here, and
		 * only for devices that support PCI PM.  Also, exiting
		 * PCI_D3 (but not PCI_D1 or PCI_D2) is allowed to reset
		 * some device state (e.g. as part of clock reinit).
		 */
		retval = pci_set_power_state (dev, PCI_D3hot);
		if (retval == 0) {
			dev_dbg (hcd->self.controller, "--> PCI D3\n");
			retval = pci_enable_wake (dev, PCI_D3hot, hcd->remote_wakeup);
			if (retval)
				break;
			retval = pci_enable_wake (dev, PCI_D3cold, hcd->remote_wakeup);
		} else if (retval < 0) {
			dev_dbg (&dev->dev, "PCI D3 suspend fail, %d\n",
					retval);
			(void) usb_hcd_pci_resume (dev);
			break;
		}
		break;
	default:
		dev_dbg (hcd->self.controller, "hcd state %d; not suspended\n",
			hcd->state);
		WARN_ON(1);
		retval = -EINVAL;
		break;
	}

	/* update power_state **ONLY** to make sysfs happier */
	if (retval == 0)
		dev->dev.power.power_state = message;
	return retval;
}
EXPORT_SYMBOL (usb_hcd_pci_suspend);

/**
 * usb_hcd_pci_resume - power management resume of a PCI-based HCD
 * @dev: USB Host Controller being resumed
 *
 * Store this function in the HCD's struct pci_driver as resume().
 */
int usb_hcd_pci_resume (struct pci_dev *dev)
{
	struct usb_hcd		*hcd;
	int			retval;

	hcd = pci_get_drvdata(dev);
	if (hcd->state != HC_STATE_SUSPENDED) {
		dev_dbg (hcd->self.controller, 
				"can't resume, not suspended!\n");
		return 0;
	}

	/* NOTE:  chip docs cover clean "real suspend" cases (what Linux
	 * calls "standby", "suspend to RAM", and so on).  There are also
	 * dirty cases when swsusp fakes a suspend in "shutdown" mode.
	 */
	if (dev->current_state != PCI_D0) {
#ifdef	DEBUG
		int	pci_pm;
		u16	pmcr;

		pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM);
		pci_read_config_word(dev, pci_pm + PCI_PM_CTRL, &pmcr);
		pmcr &= PCI_PM_CTRL_STATE_MASK;
		if (pmcr) {
			/* Clean case:  power to USB and to HC registers was
			 * maintained; remote wakeup is easy.
			 */
			dev_dbg(hcd->self.controller, "resume from PCI D%d\n",
					pmcr);
		} else {
			/* Clean:  HC lost Vcc power, D0 uninitialized
			 *   + Vaux may have preserved port and transceiver
			 *     state ... for remote wakeup from D3cold
			 *   + or not; HCD must reinit + re-enumerate
			 *
			 * Dirty: D0 semi-initialized cases with swsusp
			 *   + after BIOS init
			 *   + after Linux init (HCD statically linked)
			 */
			dev_dbg(hcd->self.controller,
				"PCI D0, from previous PCI D%d\n",
				dev->current_state);
		}
#endif
		retval = pci_enable_wake (dev, dev->current_state, 0);
		if (retval) {
			dev_err(hcd->self.controller,
				"can't enable_wake to %d, %d!\n",
				dev->current_state, retval);
			return retval;
		}
		retval = pci_enable_wake (dev, PCI_D3cold, 0);
		if (retval) {
			dev_err(hcd->self.controller,
				"can't enable_wake to %d, %d!\n",
				PCI_D3cold, retval);
			return retval;
		}
	} else {
		/* Same basic cases: clean (powered/not), dirty */
		dev_dbg(hcd->self.controller, "PCI legacy resume\n");
	}

	/* NOTE:  the PCI API itself is asymmetric here.  We don't need to
	 * pci_set_power_state(PCI_D0) since that's part of re-enabling;
	 * but that won't re-enable bus mastering.  Yet pci_disable_device()
	 * explicitly disables bus mastering...
	 */
	retval = pci_enable_device (dev);
	if (retval < 0) {
		dev_err (hcd->self.controller,
			"can't re-enable after resume, %d!\n", retval);
		return retval;
	}
	pci_set_master (dev);
	pci_restore_state (dev);

	dev->dev.power.power_state = PMSG_ON;

	hcd->state = HC_STATE_RESUMING;
	hcd->saw_irq = 0;
	retval = request_irq (dev->irq, usb_hcd_irq, SA_SHIRQ,
				hcd->irq_descr, hcd);
	if (retval < 0) {
		dev_err (hcd->self.controller,
			"can't restore IRQ after resume!\n");
		usb_hc_died (hcd);
		return retval;
	}

	retval = hcd->driver->resume (hcd);
	if (!HC_IS_RUNNING (hcd->state)) {
		dev_dbg (hcd->self.controller, 
				"resume fail, retval %d\n", retval);
		usb_hc_died (hcd);
	}

	retval = pci_enable_device(dev);
	return retval;
}
EXPORT_SYMBOL (usb_hcd_pci_resume);

#endif	/* CONFIG_PM */