epca.c: reformat comments and coding style improvements
[linux-2.6/openmoko-kernel.git] / drivers / usb / core / hcd-pci.c
blob5cf6d5f9acbdb749340b0f8922f5ec177afbe3f5
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.
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.
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.
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/pci.h>
22 #include <linux/usb.h>
24 #include <asm/io.h>
25 #include <asm/irq.h>
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
34 #include "usb.h"
35 #include "hcd.h"
38 /* PCI-based HCs are common, but plenty of non-PCI HCs are used too */
41 /*-------------------------------------------------------------------------*/
43 /* configure so an HC device and id are always provided */
44 /* always called with process context; sleeping is OK */
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()
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.
56 * Store this function in the HCD's struct pci_driver as probe().
58 int usb_hcd_pci_probe (struct pci_dev *dev, const struct pci_device_id *id)
60 struct hc_driver *driver;
61 struct usb_hcd *hcd;
62 int retval;
64 if (usb_disabled())
65 return -ENODEV;
67 if (!id || !(driver = (struct hc_driver *) id->driver_data))
68 return -EINVAL;
70 if (pci_enable_device (dev) < 0)
71 return -ENODEV;
72 dev->current_state = PCI_D0;
73 dev->dev.power.power_state = PMSG_ON;
75 if (!dev->irq) {
76 dev_err (&dev->dev,
77 "Found HC with no IRQ. Check BIOS/PCI %s setup!\n",
78 pci_name(dev));
79 retval = -ENODEV;
80 goto err1;
83 hcd = usb_create_hcd (driver, &dev->dev, pci_name(dev));
84 if (!hcd) {
85 retval = -ENOMEM;
86 goto err1;
89 if (driver->flags & HCD_MEMORY) { // EHCI, OHCI
90 hcd->rsrc_start = pci_resource_start (dev, 0);
91 hcd->rsrc_len = pci_resource_len (dev, 0);
92 if (!request_mem_region (hcd->rsrc_start, hcd->rsrc_len,
93 driver->description)) {
94 dev_dbg (&dev->dev, "controller already in use\n");
95 retval = -EBUSY;
96 goto err2;
98 hcd->regs = ioremap_nocache (hcd->rsrc_start, hcd->rsrc_len);
99 if (hcd->regs == NULL) {
100 dev_dbg (&dev->dev, "error mapping memory\n");
101 retval = -EFAULT;
102 goto err3;
105 } else { // UHCI
106 int region;
108 for (region = 0; region < PCI_ROM_RESOURCE; region++) {
109 if (!(pci_resource_flags (dev, region) &
110 IORESOURCE_IO))
111 continue;
113 hcd->rsrc_start = pci_resource_start (dev, region);
114 hcd->rsrc_len = pci_resource_len (dev, region);
115 if (request_region (hcd->rsrc_start, hcd->rsrc_len,
116 driver->description))
117 break;
119 if (region == PCI_ROM_RESOURCE) {
120 dev_dbg (&dev->dev, "no i/o regions available\n");
121 retval = -EBUSY;
122 goto err1;
126 pci_set_master (dev);
128 retval = usb_add_hcd (hcd, dev->irq, IRQF_SHARED);
129 if (retval != 0)
130 goto err4;
131 return retval;
133 err4:
134 if (driver->flags & HCD_MEMORY) {
135 iounmap (hcd->regs);
136 err3:
137 release_mem_region (hcd->rsrc_start, hcd->rsrc_len);
138 } else
139 release_region (hcd->rsrc_start, hcd->rsrc_len);
140 err2:
141 usb_put_hcd (hcd);
142 err1:
143 pci_disable_device (dev);
144 dev_err (&dev->dev, "init %s fail, %d\n", pci_name(dev), retval);
145 return retval;
147 EXPORT_SYMBOL (usb_hcd_pci_probe);
150 /* may be called without controller electrically present */
151 /* may be called with controller, bus, and devices active */
154 * usb_hcd_pci_remove - shutdown processing for PCI-based HCDs
155 * @dev: USB Host Controller being removed
156 * Context: !in_interrupt()
158 * Reverses the effect of usb_hcd_pci_probe(), first invoking
159 * the HCD's stop() method. It is always called from a thread
160 * context, normally "rmmod", "apmd", or something similar.
162 * Store this function in the HCD's struct pci_driver as remove().
164 void usb_hcd_pci_remove (struct pci_dev *dev)
166 struct usb_hcd *hcd;
168 hcd = pci_get_drvdata(dev);
169 if (!hcd)
170 return;
172 usb_remove_hcd (hcd);
173 if (hcd->driver->flags & HCD_MEMORY) {
174 iounmap (hcd->regs);
175 release_mem_region (hcd->rsrc_start, hcd->rsrc_len);
176 } else {
177 release_region (hcd->rsrc_start, hcd->rsrc_len);
179 usb_put_hcd (hcd);
180 pci_disable_device(dev);
182 EXPORT_SYMBOL (usb_hcd_pci_remove);
185 #ifdef CONFIG_PM
188 * usb_hcd_pci_suspend - power management suspend of a PCI-based HCD
189 * @dev: USB Host Controller being suspended
190 * @message: semantics in flux
192 * Store this function in the HCD's struct pci_driver as suspend().
194 int usb_hcd_pci_suspend (struct pci_dev *dev, pm_message_t message)
196 struct usb_hcd *hcd;
197 int retval = 0;
198 int has_pci_pm;
200 hcd = pci_get_drvdata(dev);
202 /* Root hub suspend should have stopped all downstream traffic,
203 * and all bus master traffic. And done so for both the interface
204 * and the stub usb_device (which we check here). But maybe it
205 * didn't; writing sysfs power/state files ignores such rules...
207 * We must ignore the FREEZE vs SUSPEND distinction here, because
208 * otherwise the swsusp will save (and restore) garbage state.
210 if (!(hcd->state == HC_STATE_SUSPENDED ||
211 hcd->state == HC_STATE_HALT))
212 return -EBUSY;
214 if (hcd->driver->suspend) {
215 retval = hcd->driver->suspend(hcd, message);
216 suspend_report_result(hcd->driver->suspend, retval);
217 if (retval)
218 goto done;
220 synchronize_irq(dev->irq);
222 /* FIXME until the generic PM interfaces change a lot more, this
223 * can't use PCI D1 and D2 states. For example, the confusion
224 * between messages and states will need to vanish, and messages
225 * will need to provide a target system state again.
227 * It'll be important to learn characteristics of the target state,
228 * especially on embedded hardware where the HCD will often be in
229 * charge of an external VBUS power supply and one or more clocks.
230 * Some target system states will leave them active; others won't.
231 * (With PCI, that's often handled by platform BIOS code.)
234 /* even when the PCI layer rejects some of the PCI calls
235 * below, HCs can try global suspend and reduce DMA traffic.
236 * PM-sensitive HCDs may already have done this.
238 has_pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM);
240 /* Downstream ports from this root hub should already be quiesced, so
241 * there will be no DMA activity. Now we can shut down the upstream
242 * link (except maybe for PME# resume signaling) and enter some PCI
243 * low power state, if the hardware allows.
245 if (hcd->state == HC_STATE_SUSPENDED) {
247 /* no DMA or IRQs except when HC is active */
248 if (dev->current_state == PCI_D0) {
249 pci_save_state (dev);
250 pci_disable_device (dev);
253 if (!has_pci_pm) {
254 dev_dbg (hcd->self.controller, "--> PCI D0/legacy\n");
255 goto done;
258 /* NOTE: dev->current_state becomes nonzero only here, and
259 * only for devices that support PCI PM. Also, exiting
260 * PCI_D3 (but not PCI_D1 or PCI_D2) is allowed to reset
261 * some device state (e.g. as part of clock reinit).
263 retval = pci_set_power_state (dev, PCI_D3hot);
264 suspend_report_result(pci_set_power_state, retval);
265 if (retval == 0) {
266 int wake = device_can_wakeup(&hcd->self.root_hub->dev);
268 wake = wake && device_may_wakeup(hcd->self.controller);
270 dev_dbg (hcd->self.controller, "--> PCI D3%s\n",
271 wake ? "/wakeup" : "");
273 /* Ignore these return values. We rely on pci code to
274 * reject requests the hardware can't implement, rather
275 * than coding the same thing.
277 (void) pci_enable_wake (dev, PCI_D3hot, wake);
278 (void) pci_enable_wake (dev, PCI_D3cold, wake);
279 } else {
280 dev_dbg (&dev->dev, "PCI D3 suspend fail, %d\n",
281 retval);
282 (void) usb_hcd_pci_resume (dev);
285 } else if (hcd->state != HC_STATE_HALT) {
286 dev_dbg (hcd->self.controller, "hcd state %d; not suspended\n",
287 hcd->state);
288 WARN_ON(1);
289 retval = -EINVAL;
292 done:
293 if (retval == 0) {
294 dev->dev.power.power_state = PMSG_SUSPEND;
296 #ifdef CONFIG_PPC_PMAC
297 /* Disable ASIC clocks for USB */
298 if (machine_is(powermac)) {
299 struct device_node *of_node;
301 of_node = pci_device_to_OF_node (dev);
302 if (of_node)
303 pmac_call_feature(PMAC_FTR_USB_ENABLE,
304 of_node, 0, 0);
306 #endif
309 return retval;
311 EXPORT_SYMBOL (usb_hcd_pci_suspend);
314 * usb_hcd_pci_resume - power management resume of a PCI-based HCD
315 * @dev: USB Host Controller being resumed
317 * Store this function in the HCD's struct pci_driver as resume().
319 int usb_hcd_pci_resume (struct pci_dev *dev)
321 struct usb_hcd *hcd;
322 int retval;
324 hcd = pci_get_drvdata(dev);
325 if (hcd->state != HC_STATE_SUSPENDED) {
326 dev_dbg (hcd->self.controller,
327 "can't resume, not suspended!\n");
328 return 0;
331 #ifdef CONFIG_PPC_PMAC
332 /* Reenable ASIC clocks for USB */
333 if (machine_is(powermac)) {
334 struct device_node *of_node;
336 of_node = pci_device_to_OF_node (dev);
337 if (of_node)
338 pmac_call_feature (PMAC_FTR_USB_ENABLE,
339 of_node, 0, 1);
341 #endif
343 /* NOTE: chip docs cover clean "real suspend" cases (what Linux
344 * calls "standby", "suspend to RAM", and so on). There are also
345 * dirty cases when swsusp fakes a suspend in "shutdown" mode.
347 if (dev->current_state != PCI_D0) {
348 #ifdef DEBUG
349 int pci_pm;
350 u16 pmcr;
352 pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM);
353 pci_read_config_word(dev, pci_pm + PCI_PM_CTRL, &pmcr);
354 pmcr &= PCI_PM_CTRL_STATE_MASK;
355 if (pmcr) {
356 /* Clean case: power to USB and to HC registers was
357 * maintained; remote wakeup is easy.
359 dev_dbg(hcd->self.controller, "resume from PCI D%d\n",
360 pmcr);
361 } else {
362 /* Clean: HC lost Vcc power, D0 uninitialized
363 * + Vaux may have preserved port and transceiver
364 * state ... for remote wakeup from D3cold
365 * + or not; HCD must reinit + re-enumerate
367 * Dirty: D0 semi-initialized cases with swsusp
368 * + after BIOS init
369 * + after Linux init (HCD statically linked)
371 dev_dbg(hcd->self.controller,
372 "PCI D0, from previous PCI D%d\n",
373 dev->current_state);
375 #endif
376 /* yes, ignore these results too... */
377 (void) pci_enable_wake (dev, dev->current_state, 0);
378 (void) pci_enable_wake (dev, PCI_D3cold, 0);
379 } else {
380 /* Same basic cases: clean (powered/not), dirty */
381 dev_dbg(hcd->self.controller, "PCI legacy resume\n");
384 /* NOTE: the PCI API itself is asymmetric here. We don't need to
385 * pci_set_power_state(PCI_D0) since that's part of re-enabling;
386 * but that won't re-enable bus mastering. Yet pci_disable_device()
387 * explicitly disables bus mastering...
389 retval = pci_enable_device (dev);
390 if (retval < 0) {
391 dev_err (hcd->self.controller,
392 "can't re-enable after resume, %d!\n", retval);
393 return retval;
395 pci_set_master (dev);
396 pci_restore_state (dev);
398 dev->dev.power.power_state = PMSG_ON;
400 clear_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
402 if (hcd->driver->resume) {
403 retval = hcd->driver->resume(hcd);
404 if (retval) {
405 dev_err (hcd->self.controller,
406 "PCI post-resume error %d!\n", retval);
407 usb_hc_died (hcd);
411 return retval;
413 EXPORT_SYMBOL (usb_hcd_pci_resume);
415 #endif /* CONFIG_PM */
418 * usb_hcd_pci_shutdown - shutdown host controller
419 * @dev: USB Host Controller being shutdown
421 void usb_hcd_pci_shutdown (struct pci_dev *dev)
423 struct usb_hcd *hcd;
425 hcd = pci_get_drvdata(dev);
426 if (!hcd)
427 return;
429 if (hcd->driver->shutdown)
430 hcd->driver->shutdown(hcd);
432 EXPORT_SYMBOL (usb_hcd_pci_shutdown);