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