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 <linux/usb.h>
  24
  25 #include <asm/io.h>
  26 #include <asm/irq.h>
  27
  28 #ifdef CONFIG_PPC_PMAC
  29 #include <asm/machdep.h>
  30 #include <asm/pmac_feature.h>
  31 #include <asm/pci-bridge.h>
  32 #include <asm/prom.h>
  33 #endif
  34
  35 #include "usb.h"
  36 #include "hcd.h"
  37
  38
  39 /* PCI-based HCs are common, but plenty of non-PCI HCs are used too */
  40
  41
  42 /*-------------------------------------------------------------------------*/
  43
  44 /* configure so an HC device and id are always provided */
  45 /* always called with process context; sleeping is OK */
  46
  47 /**
  48  * usb_hcd_pci_probe - initialize PCI-based HCDs
  49  * @dev: USB Host Controller being probed
  50  * @id: pci hotplug id connecting controller to HCD framework
  51  * Context: !in_interrupt()
  52  *
  53  * Allocates basic PCI resources for this USB host controller, and
  54  * then invokes the start() method for the HCD associated with it
  55  * through the hotplug entry's driver_data.
  56  *
  57  * Store this function in the HCD's struct pci_driver as probe().
  58  */
  59 int usb_hcd_pci_probe (struct pci_dev *dev, const struct pci_device_id *id)
  60 {
  61         struct hc_driver        *driver;
  62         struct usb_hcd          *hcd;
  63         int                     retval;
  64
  65         if (usb_disabled())
  66                 return -ENODEV;
  67
  68         if (!id || !(driver = (struct hc_driver *) id->driver_data))
  69                 return -EINVAL;
  70
  71         if (pci_enable_device (dev) < 0)
  72                 return -ENODEV;
  73         dev->current_state = PCI_D0;
  74         dev->dev.power.power_state = PMSG_ON;
  75
  76         if (!dev->irq) {
  77                 dev_err (&dev->dev,
  78                         "Found HC with no IRQ.  Check BIOS/PCI %s setup!\n",
  79                         pci_name(dev));
  80                 retval = -ENODEV;
  81                 goto err1;
  82         }
  83
  84         hcd = usb_create_hcd (driver, &dev->dev, pci_name(dev));
  85         if (!hcd) {
  86                 retval = -ENOMEM;
  87                 goto err1;
  88         }
  89
  90         if (driver->flags & HCD_MEMORY) {       // EHCI, OHCI
  91                 hcd->rsrc_start = pci_resource_start (dev, 0);
  92                 hcd->rsrc_len = pci_resource_len (dev, 0);
  93                 if (!request_mem_region (hcd->rsrc_start, hcd->rsrc_len,
  94                                 driver->description)) {
  95                         dev_dbg (&dev->dev, "controller already in use\n");
  96                         retval = -EBUSY;
  97                         goto err2;
  98                 }
  99                 hcd->regs = ioremap_nocache (hcd->rsrc_start, hcd->rsrc_len);
 100                 if (hcd->regs == NULL) {
 101                         dev_dbg (&dev->dev, "error mapping memory\n");
 102                         retval = -EFAULT;
 103                         goto err3;
 104                 }
 105
 106         } else {                                // UHCI
 107                 int     region;
 108
 109                 for (region = 0; region < PCI_ROM_RESOURCE; region++) {
 110                         if (!(pci_resource_flags (dev, region) &
 111                                         IORESOURCE_IO))
 112                                 continue;
 113
 114                         hcd->rsrc_start = pci_resource_start (dev, region);
 115                         hcd->rsrc_len = pci_resource_len (dev, region);
 116                         if (request_region (hcd->rsrc_start, hcd->rsrc_len,
 117                                         driver->description))
 118                                 break;
 119                 }
 120                 if (region == PCI_ROM_RESOURCE) {
 121                         dev_dbg (&dev->dev, "no i/o regions available\n");
 122                         retval = -EBUSY;
 123                         goto err1;
 124                 }
 125         }
 126
 127         pci_set_master (dev);
 128
 129         retval = usb_add_hcd (hcd, dev->irq, SA_SHIRQ);
 130         if (retval != 0)
 131                 goto err4;
 132         return retval;
 133
 134  err4:
 135         if (driver->flags & HCD_MEMORY) {
 136                 iounmap (hcd->regs);
 137  err3:
 138                 release_mem_region (hcd->rsrc_start, hcd->rsrc_len);
 139         } else
 140                 release_region (hcd->rsrc_start, hcd->rsrc_len);
 141  err2:
 142         usb_put_hcd (hcd);
 143  err1:
 144         pci_disable_device (dev);
 145         dev_err (&dev->dev, "init %s fail, %d\n", pci_name(dev), retval);
 146         return retval;
 147 }
 148 EXPORT_SYMBOL (usb_hcd_pci_probe);
 149
 150
 151 /* may be called without controller electrically present */
 152 /* may be called with controller, bus, and devices active */
 153
 154 /**
 155  * usb_hcd_pci_remove - shutdown processing for PCI-based HCDs
 156  * @dev: USB Host Controller being removed
 157  * Context: !in_interrupt()
 158  *
 159  * Reverses the effect of usb_hcd_pci_probe(), first invoking
 160  * the HCD's stop() method.  It is always called from a thread
 161  * context, normally "rmmod", "apmd", or something similar.
 162  *
 163  * Store this function in the HCD's struct pci_driver as remove().
 164  */
 165 void usb_hcd_pci_remove (struct pci_dev *dev)
 166 {
 167         struct usb_hcd          *hcd;
 168
 169         hcd = pci_get_drvdata(dev);
 170         if (!hcd)
 171                 return;
 172
 173         usb_remove_hcd (hcd);
 174         if (hcd->driver->flags & HCD_MEMORY) {
 175                 iounmap (hcd->regs);
 176                 release_mem_region (hcd->rsrc_start, hcd->rsrc_len);
 177         } else {
 178                 release_region (hcd->rsrc_start, hcd->rsrc_len);
 179         }
 180         usb_put_hcd (hcd);
 181         pci_disable_device(dev);
 182 }
 183 EXPORT_SYMBOL (usb_hcd_pci_remove);
 184
 185
 186 #ifdef  CONFIG_PM
 187
 188 /**
 189  * usb_hcd_pci_suspend - power management suspend of a PCI-based HCD
 190  * @dev: USB Host Controller being suspended
 191  * @message: semantics in flux
 192  *
 193  * Store this function in the HCD's struct pci_driver as suspend().
 194  */
 195 int usb_hcd_pci_suspend (struct pci_dev *dev, pm_message_t message)
 196 {
 197         struct usb_hcd          *hcd;
 198         int                     retval = 0;
 199         int                     has_pci_pm;
 200
 201         hcd = pci_get_drvdata(dev);
 202
 203         /* Root hub suspend should have stopped all downstream traffic,
 204          * and all bus master traffic.  And done so for both the interface
 205          * and the stub usb_device (which we check here).  But maybe it
 206          * didn't; writing sysfs power/state files ignores such rules...
 207          *
 208          * We must ignore the FREEZE vs SUSPEND distinction here, because
 209          * otherwise the swsusp will save (and restore) garbage state.
 210          */
 211         if (hcd->self.root_hub->dev.power.power_state.event == PM_EVENT_ON)
 212                 return -EBUSY;
 213
 214         if (hcd->driver->suspend) {
 215                 retval = hcd->driver->suspend(hcd, message);
 216                 if (retval) {
 217                         dev_dbg (&dev->dev, "PCI pre-suspend fail, %d\n",
 218                                 retval);
 219                         goto done;
 220                 }
 221         }
 222         synchronize_irq(dev->irq);
 223
 224         /* FIXME until the generic PM interfaces change a lot more, this
 225          * can't use PCI D1 and D2 states.  For example, the confusion
 226          * between messages and states will need to vanish, and messages
 227          * will need to provide a target system state again.
 228          *
 229          * It'll be important to learn characteristics of the target state,
 230          * especially on embedded hardware where the HCD will often be in
 231          * charge of an external VBUS power supply and one or more clocks.
 232          * Some target system states will leave them active; others won't.
 233          * (With PCI, that's often handled by platform BIOS code.)
 234          */
 235
 236         /* even when the PCI layer rejects some of the PCI calls
 237          * below, HCs can try global suspend and reduce DMA traffic.
 238          * PM-sensitive HCDs may already have done this.
 239          */
 240         has_pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM);
 241
 242         /* Downstream ports from this root hub should already be quiesced, so
 243          * there will be no DMA activity.  Now we can shut down the upstream
 244          * link (except maybe for PME# resume signaling) and enter some PCI
 245          * low power state, if the hardware allows.
 246          */
 247         if (hcd->state == HC_STATE_SUSPENDED) {
 248
 249                 /* no DMA or IRQs except when HC is active */
 250                 if (dev->current_state == PCI_D0) {
 251                         pci_save_state (dev);
 252                         pci_disable_device (dev);
 253                 }
 254
 255                 if (!has_pci_pm) {
 256                         dev_dbg (hcd->self.controller, "--> PCI D0/legacy\n");
 257                         goto done;
 258                 }
 259
 260                 /* NOTE:  dev->current_state becomes nonzero only here, and
 261                  * only for devices that support PCI PM.  Also, exiting
 262                  * PCI_D3 (but not PCI_D1 or PCI_D2) is allowed to reset
 263                  * some device state (e.g. as part of clock reinit).
 264                  */
 265                 retval = pci_set_power_state (dev, PCI_D3hot);
 266                 if (retval == 0) {
 267                         dev_dbg (hcd->self.controller, "--> PCI D3\n");
 268
 269                         /* Ignore these return values.  We rely on pci code to
 270                          * reject requests the hardware can't implement, rather
 271                          * than coding the same thing.
 272                          */
 273                         (void) pci_enable_wake (dev, PCI_D3hot, hcd->remote_wakeup);
 274                         (void) pci_enable_wake (dev, PCI_D3cold, hcd->remote_wakeup);
 275                 } else {
 276                         dev_dbg (&dev->dev, "PCI D3 suspend fail, %d\n",
 277                                         retval);
 278                         (void) usb_hcd_pci_resume (dev);
 279                 }
 280
 281         } else {
 282                 dev_dbg (hcd->self.controller, "hcd state %d; not suspended\n",
 283                         hcd->state);
 284                 WARN_ON(1);
 285                 retval = -EINVAL;
 286         }
 287
 288 done:
 289         if (retval == 0) {
 290                 dev->dev.power.power_state = PMSG_SUSPEND;
 291
 292 #ifdef CONFIG_PPC_PMAC
 293                 /* Disable ASIC clocks for USB */
 294                 if (_machine == _MACH_Pmac) {
 295                         struct device_node      *of_node;
 296
 297                         of_node = pci_device_to_OF_node (dev);
 298                         if (of_node)
 299                                 pmac_call_feature(PMAC_FTR_USB_ENABLE,
 300                                                         of_node, 0, 0);
 301                 }
 302 #endif
 303         }
 304
 305         return retval;
 306 }
 307 EXPORT_SYMBOL (usb_hcd_pci_suspend);
 308
 309 /**
 310  * usb_hcd_pci_resume - power management resume of a PCI-based HCD
 311  * @dev: USB Host Controller being resumed
 312  *
 313  * Store this function in the HCD's struct pci_driver as resume().
 314  */
 315 int usb_hcd_pci_resume (struct pci_dev *dev)
 316 {
 317         struct usb_hcd          *hcd;
 318         int                     retval;
 319
 320         hcd = pci_get_drvdata(dev);
 321         if (hcd->state != HC_STATE_SUSPENDED) {
 322                 dev_dbg (hcd->self.controller,
 323                                 "can't resume, not suspended!\n");
 324                 return 0;
 325         }
 326
 327 #ifdef CONFIG_PPC_PMAC
 328         /* Reenable ASIC clocks for USB */
 329         if (_machine == _MACH_Pmac) {
 330                 struct device_node *of_node;
 331
 332                 of_node = pci_device_to_OF_node (dev);
 333                 if (of_node)
 334                         pmac_call_feature (PMAC_FTR_USB_ENABLE,
 335                                                 of_node, 0, 1);
 336         }
 337 #endif
 338
 339         /* NOTE:  chip docs cover clean "real suspend" cases (what Linux
 340          * calls "standby", "suspend to RAM", and so on).  There are also
 341          * dirty cases when swsusp fakes a suspend in "shutdown" mode.
 342          */
 343         if (dev->current_state != PCI_D0) {
 344 #ifdef  DEBUG
 345                 int     pci_pm;
 346                 u16     pmcr;
 347
 348                 pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM);
 349                 pci_read_config_word(dev, pci_pm + PCI_PM_CTRL, &pmcr);
 350                 pmcr &= PCI_PM_CTRL_STATE_MASK;
 351                 if (pmcr) {
 352                         /* Clean case:  power to USB and to HC registers was
 353                          * maintained; remote wakeup is easy.
 354                          */
 355                         dev_dbg(hcd->self.controller, "resume from PCI D%d\n",
 356                                         pmcr);
 357                 } else {
 358                         /* Clean:  HC lost Vcc power, D0 uninitialized
 359                          *   + Vaux may have preserved port and transceiver
 360                          *     state ... for remote wakeup from D3cold
 361                          *   + or not; HCD must reinit + re-enumerate
 362                          *
 363                          * Dirty: D0 semi-initialized cases with swsusp
 364                          *   + after BIOS init
 365                          *   + after Linux init (HCD statically linked)
 366                          */
 367                         dev_dbg(hcd->self.controller,
 368                                 "PCI D0, from previous PCI D%d\n",
 369                                 dev->current_state);
 370                 }
 371 #endif
 372                 /* yes, ignore these results too... */
 373                 (void) pci_enable_wake (dev, dev->current_state, 0);
 374                 (void) pci_enable_wake (dev, PCI_D3cold, 0);
 375         } else {
 376                 /* Same basic cases: clean (powered/not), dirty */
 377                 dev_dbg(hcd->self.controller, "PCI legacy resume\n");
 378         }
 379
 380         /* NOTE:  the PCI API itself is asymmetric here.  We don't need to
 381          * pci_set_power_state(PCI_D0) since that's part of re-enabling;
 382          * but that won't re-enable bus mastering.  Yet pci_disable_device()
 383          * explicitly disables bus mastering...
 384          */
 385         retval = pci_enable_device (dev);
 386         if (retval < 0) {
 387                 dev_err (hcd->self.controller,
 388                         "can't re-enable after resume, %d!\n", retval);
 389                 return retval;
 390         }
 391         pci_set_master (dev);
 392         pci_restore_state (dev);
 393
 394         dev->dev.power.power_state = PMSG_ON;
 395
 396         clear_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
 397
 398         if (hcd->driver->resume) {
 399                 retval = hcd->driver->resume(hcd);
 400                 if (retval) {
 401                         dev_err (hcd->self.controller,
 402                                 "PCI post-resume error %d!\n", retval);
 403                         usb_hc_died (hcd);
 404                 }
 405         }
 406
 407         return retval;
 408 }
 409 EXPORT_SYMBOL (usb_hcd_pci_resume);
 410
 411 #endif  /* CONFIG_PM */
 412
 413