drivers/usb/core/hcd-pci.c

   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 || !(driver = (struct hc_driver *) id->driver_data))
  68                 return -EINVAL;
  69
  70         if (pci_enable_device (dev) < 0)
  71                 return -ENODEV;
  72         dev->current_state = PCI_D0;
  73         dev->dev.power.power_state = PMSG_ON;
  74
  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;
  81         }
  82
  83         hcd = usb_create_hcd (driver, &dev->dev, pci_name(dev));
  84         if (!hcd) {
  85                 retval = -ENOMEM;
  86                 goto err1;
  87         }
  88
  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;
  97                 }
  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;
 103                 }
 104
 105         } else {                                // UHCI
 106                 int     region;
 107
 108                 for (region = 0; region < PCI_ROM_RESOURCE; region++) {
 109                         if (!(pci_resource_flags (dev, region) &
 110                                         IORESOURCE_IO))
 111                                 continue;
 112
 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;
 118                 }
 119                 if (region == PCI_ROM_RESOURCE) {
 120                         dev_dbg (&dev->dev, "no i/o regions available\n");
 121                         retval = -EBUSY;
 122                         goto err1;
 123                 }
 124         }
 125
 126         pci_set_master (dev);
 127
 128         retval = usb_add_hcd (hcd, dev->irq, IRQF_SHARED);
 129         if (retval != 0)
 130                 goto err4;
 131         return retval;
 132
 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;
 146 }
 147 EXPORT_SYMBOL (usb_hcd_pci_probe);
 148
 149
 150 /* may be called without controller electrically present */
 151 /* may be called with controller, bus, and devices active */
 152
 153 /**
 154  * usb_hcd_pci_remove - shutdown processing for PCI-based HCDs
 155  * @dev: USB Host Controller being removed
 156  * Context: !in_interrupt()
 157  *
 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.
 161  *
 162  * Store this function in the HCD's struct pci_driver as remove().
 163  */
 164 void usb_hcd_pci_remove (struct pci_dev *dev)
 165 {
 166         struct usb_hcd          *hcd;
 167
 168         hcd = pci_get_drvdata(dev);
 169         if (!hcd)
 170                 return;
 171
 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);
 178         }
 179         usb_put_hcd (hcd);
 180         pci_disable_device(dev);
 181 }
 182 EXPORT_SYMBOL (usb_hcd_pci_remove);
 183
 184
 185 #ifdef  CONFIG_PM
 186
 187 /**
 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
 191  *
 192  * Store this function in the HCD's struct pci_driver as suspend().
 193  */
 194 int usb_hcd_pci_suspend (struct pci_dev *dev, pm_message_t message)
 195 {
 196         struct usb_hcd          *hcd;
 197         int                     retval = 0;
 198         int                     has_pci_pm;
 199
 200         hcd = pci_get_drvdata(dev);
 201
 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...
 206          *
 207          * We must ignore the FREEZE vs SUSPEND distinction here, because
 208          * otherwise the swsusp will save (and restore) garbage state.
 209          */
 210         if (hcd->self.root_hub->dev.power.power_state.event == PM_EVENT_ON)
 211                 return -EBUSY;
 212
 213         if (hcd->driver->suspend) {
 214                 retval = hcd->driver->suspend(hcd, message);
 215                 suspend_report_result(hcd->driver->suspend, retval);
 216                 if (retval)
 217                         goto done;
 218         }
 219         synchronize_irq(dev->irq);
 220
 221         /* FIXME until the generic PM interfaces change a lot more, this
 222          * can't use PCI D1 and D2 states.  For example, the confusion
 223          * between messages and states will need to vanish, and messages
 224          * will need to provide a target system state again.
 225          *
 226          * It'll be important to learn characteristics of the target state,
 227          * especially on embedded hardware where the HCD will often be in
 228          * charge of an external VBUS power supply and one or more clocks.
 229          * Some target system states will leave them active; others won't.
 230          * (With PCI, that's often handled by platform BIOS code.)
 231          */
 232
 233         /* even when the PCI layer rejects some of the PCI calls
 234          * below, HCs can try global suspend and reduce DMA traffic.
 235          * PM-sensitive HCDs may already have done this.
 236          */
 237         has_pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM);
 238
 239         /* Downstream ports from this root hub should already be quiesced, so
 240          * there will be no DMA activity.  Now we can shut down the upstream
 241          * link (except maybe for PME# resume signaling) and enter some PCI
 242          * low power state, if the hardware allows.
 243          */
 244         if (hcd->state == HC_STATE_SUSPENDED) {
 245
 246                 /* no DMA or IRQs except when HC is active */
 247                 if (dev->current_state == PCI_D0) {
 248                         pci_save_state (dev);
 249                         pci_disable_device (dev);
 250                 }
 251
 252                 if (!has_pci_pm) {
 253                         dev_dbg (hcd->self.controller, "--> PCI D0/legacy\n");
 254                         goto done;
 255                 }
 256
 257                 /* NOTE:  dev->current_state becomes nonzero only here, and
 258                  * only for devices that support PCI PM.  Also, exiting
 259                  * PCI_D3 (but not PCI_D1 or PCI_D2) is allowed to reset
 260                  * some device state (e.g. as part of clock reinit).
 261                  */
 262                 retval = pci_set_power_state (dev, PCI_D3hot);
 263                 suspend_report_result(pci_set_power_state, retval);
 264                 if (retval == 0) {
 265                         int wake = device_can_wakeup(&hcd->self.root_hub->dev);
 266
 267                         wake = wake && device_may_wakeup(hcd->self.controller);
 268
 269                         dev_dbg (hcd->self.controller, "--> PCI D3%s\n",
 270                                         wake ? "/wakeup" : "");
 271
 272                         /* Ignore these return values.  We rely on pci code to
 273                          * reject requests the hardware can't implement, rather
 274                          * than coding the same thing.
 275                          */
 276                         (void) pci_enable_wake (dev, PCI_D3hot, wake);
 277                         (void) pci_enable_wake (dev, PCI_D3cold, wake);
 278                 } else {
 279                         dev_dbg (&dev->dev, "PCI D3 suspend fail, %d\n",
 280                                         retval);
 281                         (void) usb_hcd_pci_resume (dev);
 282                 }
 283
 284         } else {
 285                 dev_dbg (hcd->self.controller, "hcd state %d; not suspended\n",
 286                         hcd->state);
 287                 WARN_ON(1);
 288                 retval = -EINVAL;
 289         }
 290
 291 done:
 292         if (retval == 0) {
 293                 dev->dev.power.power_state = PMSG_SUSPEND;
 294
 295 #ifdef CONFIG_PPC_PMAC
 296                 /* Disable ASIC clocks for USB */
 297                 if (machine_is(powermac)) {
 298                         struct device_node      *of_node;
 299
 300                         of_node = pci_device_to_OF_node (dev);
 301                         if (of_node)
 302                                 pmac_call_feature(PMAC_FTR_USB_ENABLE,
 303                                                         of_node, 0, 0);
 304                 }
 305 #endif
 306         }
 307
 308         return retval;
 309 }
 310 EXPORT_SYMBOL (usb_hcd_pci_suspend);
 311
 312 /**
 313  * usb_hcd_pci_resume - power management resume of a PCI-based HCD
 314  * @dev: USB Host Controller being resumed
 315  *
 316  * Store this function in the HCD's struct pci_driver as resume().
 317  */
 318 int usb_hcd_pci_resume (struct pci_dev *dev)
 319 {
 320         struct usb_hcd          *hcd;
 321         int                     retval;
 322
 323         hcd = pci_get_drvdata(dev);
 324         if (hcd->state != HC_STATE_SUSPENDED) {
 325                 dev_dbg (hcd->self.controller,
 326                                 "can't resume, not suspended!\n");
 327                 return 0;
 328         }
 329
 330 #ifdef CONFIG_PPC_PMAC
 331         /* Reenable ASIC clocks for USB */
 332         if (machine_is(powermac)) {
 333                 struct device_node *of_node;
 334
 335                 of_node = pci_device_to_OF_node (dev);
 336                 if (of_node)
 337                         pmac_call_feature (PMAC_FTR_USB_ENABLE,
 338                                                 of_node, 0, 1);
 339         }
 340 #endif
 341
 342         /* NOTE:  chip docs cover clean "real suspend" cases (what Linux
 343          * calls "standby", "suspend to RAM", and so on).  There are also
 344          * dirty cases when swsusp fakes a suspend in "shutdown" mode.
 345          */
 346         if (dev->current_state != PCI_D0) {
 347 #ifdef  DEBUG
 348                 int     pci_pm;
 349                 u16     pmcr;
 350
 351                 pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM);
 352                 pci_read_config_word(dev, pci_pm + PCI_PM_CTRL, &pmcr);
 353                 pmcr &= PCI_PM_CTRL_STATE_MASK;
 354                 if (pmcr) {
 355                         /* Clean case:  power to USB and to HC registers was
 356                          * maintained; remote wakeup is easy.
 357                          */
 358                         dev_dbg(hcd->self.controller, "resume from PCI D%d\n",
 359                                         pmcr);
 360                 } else {
 361                         /* Clean:  HC lost Vcc power, D0 uninitialized
 362                          *   + Vaux may have preserved port and transceiver
 363                          *     state ... for remote wakeup from D3cold
 364                          *   + or not; HCD must reinit + re-enumerate
 365                          *
 366                          * Dirty: D0 semi-initialized cases with swsusp
 367                          *   + after BIOS init
 368                          *   + after Linux init (HCD statically linked)
 369                          */
 370                         dev_dbg(hcd->self.controller,
 371                                 "PCI D0, from previous PCI D%d\n",
 372                                 dev->current_state);
 373                 }
 374 #endif
 375                 /* yes, ignore these results too... */
 376                 (void) pci_enable_wake (dev, dev->current_state, 0);
 377                 (void) pci_enable_wake (dev, PCI_D3cold, 0);
 378         } else {
 379                 /* Same basic cases: clean (powered/not), dirty */
 380                 dev_dbg(hcd->self.controller, "PCI legacy resume\n");
 381         }
 382
 383         /* NOTE:  the PCI API itself is asymmetric here.  We don't need to
 384          * pci_set_power_state(PCI_D0) since that's part of re-enabling;
 385          * but that won't re-enable bus mastering.  Yet pci_disable_device()
 386          * explicitly disables bus mastering...
 387          */
 388         retval = pci_enable_device (dev);
 389         if (retval < 0) {
 390                 dev_err (hcd->self.controller,
 391                         "can't re-enable after resume, %d!\n", retval);
 392                 return retval;
 393         }
 394         pci_set_master (dev);
 395         pci_restore_state (dev);
 396
 397         dev->dev.power.power_state = PMSG_ON;
 398
 399         clear_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
 400
 401         if (hcd->driver->resume) {
 402                 retval = hcd->driver->resume(hcd);
 403                 if (retval) {
 404                         dev_err (hcd->self.controller,
 405                                 "PCI post-resume error %d!\n", retval);
 406                         usb_hc_died (hcd);
 407                 }
 408         }
 409
 410         return retval;
 411 }
 412 EXPORT_SYMBOL (usb_hcd_pci_resume);
 413
 414 #endif  /* CONFIG_PM */
 415
 416