linux/drivers/usb/core/hcd-pci.c
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   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 */
  58int 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)
  68                return -EINVAL;
  69        driver = (struct hc_driver *)id->driver_data;
  70        if (!driver)
  71                return -EINVAL;
  72
  73        if (pci_enable_device(dev) < 0)
  74                return -ENODEV;
  75        dev->current_state = PCI_D0;
  76
  77        if (!dev->irq) {
  78                dev_err(&dev->dev,
  79                        "Found HC with no IRQ.  Check BIOS/PCI %s setup!\n",
  80                        pci_name(dev));
  81                retval = -ENODEV;
  82                goto err1;
  83        }
  84
  85        hcd = usb_create_hcd(driver, &dev->dev, pci_name(dev));
  86        if (!hcd) {
  87                retval = -ENOMEM;
  88                goto err1;
  89        }
  90
  91        if (driver->flags & HCD_MEMORY) {
  92                /* EHCI, OHCI */
  93                hcd->rsrc_start = pci_resource_start(dev, 0);
  94                hcd->rsrc_len = pci_resource_len(dev, 0);
  95                if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len,
  96                                driver->description)) {
  97                        dev_dbg(&dev->dev, "controller already in use\n");
  98                        retval = -EBUSY;
  99                        goto err2;
 100                }
 101                hcd->regs = ioremap_nocache(hcd->rsrc_start, hcd->rsrc_len);
 102                if (hcd->regs == NULL) {
 103                        dev_dbg(&dev->dev, "error mapping memory\n");
 104                        retval = -EFAULT;
 105                        goto err3;
 106                }
 107
 108        } else {
 109                /* UHCI */
 110                int     region;
 111
 112                for (region = 0; region < PCI_ROM_RESOURCE; region++) {
 113                        if (!(pci_resource_flags(dev, region) &
 114                                        IORESOURCE_IO))
 115                                continue;
 116
 117                        hcd->rsrc_start = pci_resource_start(dev, region);
 118                        hcd->rsrc_len = pci_resource_len(dev, region);
 119                        if (request_region(hcd->rsrc_start, hcd->rsrc_len,
 120                                        driver->description))
 121                                break;
 122                }
 123                if (region == PCI_ROM_RESOURCE) {
 124                        dev_dbg(&dev->dev, "no i/o regions available\n");
 125                        retval = -EBUSY;
 126                        goto err1;
 127                }
 128        }
 129
 130        pci_set_master(dev);
 131
 132        retval = usb_add_hcd(hcd, dev->irq, IRQF_DISABLED | IRQF_SHARED);
 133        if (retval != 0)
 134                goto err4;
 135        return retval;
 136
 137 err4:
 138        if (driver->flags & HCD_MEMORY) {
 139                iounmap(hcd->regs);
 140 err3:
 141                release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
 142        } else
 143                release_region(hcd->rsrc_start, hcd->rsrc_len);
 144 err2:
 145        usb_put_hcd(hcd);
 146 err1:
 147        pci_disable_device(dev);
 148        dev_err(&dev->dev, "init %s fail, %d\n", pci_name(dev), retval);
 149        return retval;
 150}
 151EXPORT_SYMBOL_GPL(usb_hcd_pci_probe);
 152
 153
 154/* may be called without controller electrically present */
 155/* may be called with controller, bus, and devices active */
 156
 157/**
 158 * usb_hcd_pci_remove - shutdown processing for PCI-based HCDs
 159 * @dev: USB Host Controller being removed
 160 * Context: !in_interrupt()
 161 *
 162 * Reverses the effect of usb_hcd_pci_probe(), first invoking
 163 * the HCD's stop() method.  It is always called from a thread
 164 * context, normally "rmmod", "apmd", or something similar.
 165 *
 166 * Store this function in the HCD's struct pci_driver as remove().
 167 */
 168void usb_hcd_pci_remove(struct pci_dev *dev)
 169{
 170        struct usb_hcd          *hcd;
 171
 172        hcd = pci_get_drvdata(dev);
 173        if (!hcd)
 174                return;
 175
 176        usb_remove_hcd(hcd);
 177        if (hcd->driver->flags & HCD_MEMORY) {
 178                iounmap(hcd->regs);
 179                release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
 180        } else {
 181                release_region(hcd->rsrc_start, hcd->rsrc_len);
 182        }
 183        usb_put_hcd(hcd);
 184        pci_disable_device(dev);
 185}
 186EXPORT_SYMBOL_GPL(usb_hcd_pci_remove);
 187
 188
 189#ifdef  CONFIG_PM
 190
 191/**
 192 * usb_hcd_pci_suspend - power management suspend of a PCI-based HCD
 193 * @dev: USB Host Controller being suspended
 194 * @message: semantics in flux
 195 *
 196 * Store this function in the HCD's struct pci_driver as suspend().
 197 */
 198int usb_hcd_pci_suspend(struct pci_dev *dev, pm_message_t message)
 199{
 200        struct usb_hcd          *hcd;
 201        int                     retval = 0;
 202        int                     has_pci_pm;
 203
 204        hcd = pci_get_drvdata(dev);
 205
 206        /* Root hub suspend should have stopped all downstream traffic,
 207         * and all bus master traffic.  And done so for both the interface
 208         * and the stub usb_device (which we check here).  But maybe it
 209         * didn't; writing sysfs power/state files ignores such rules...
 210         *
 211         * We must ignore the FREEZE vs SUSPEND distinction here, because
 212         * otherwise the swsusp will save (and restore) garbage state.
 213         */
 214        if (!(hcd->state == HC_STATE_SUSPENDED ||
 215                        hcd->state == HC_STATE_HALT))
 216                return -EBUSY;
 217
 218        if (hcd->driver->pci_suspend) {
 219                retval = hcd->driver->pci_suspend(hcd, message);
 220                suspend_report_result(hcd->driver->pci_suspend, retval);
 221                if (retval)
 222                        goto done;
 223        }
 224        synchronize_irq(dev->irq);
 225
 226        /* FIXME until the generic PM interfaces change a lot more, this
 227         * can't use PCI D1 and D2 states.  For example, the confusion
 228         * between messages and states will need to vanish, and messages
 229         * will need to provide a target system state again.
 230         *
 231         * It'll be important to learn characteristics of the target state,
 232         * especially on embedded hardware where the HCD will often be in
 233         * charge of an external VBUS power supply and one or more clocks.
 234         * Some target system states will leave them active; others won't.
 235         * (With PCI, that's often handled by platform BIOS code.)
 236         */
 237
 238        /* even when the PCI layer rejects some of the PCI calls
 239         * below, HCs can try global suspend and reduce DMA traffic.
 240         * PM-sensitive HCDs may already have done this.
 241         */
 242        has_pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM);
 243
 244        /* Downstream ports from this root hub should already be quiesced, so
 245         * there will be no DMA activity.  Now we can shut down the upstream
 246         * link (except maybe for PME# resume signaling) and enter some PCI
 247         * low power state, if the hardware allows.
 248         */
 249        if (hcd->state == HC_STATE_SUSPENDED) {
 250
 251                /* no DMA or IRQs except when HC is active */
 252                if (dev->current_state == PCI_D0) {
 253                        pci_save_state(dev);
 254                        pci_disable_device(dev);
 255                }
 256
 257                if (message.event == PM_EVENT_FREEZE ||
 258                                message.event == PM_EVENT_PRETHAW) {
 259                        dev_dbg(hcd->self.controller, "--> no state change\n");
 260                        goto done;
 261                }
 262
 263                if (!has_pci_pm) {
 264                        dev_dbg(hcd->self.controller, "--> PCI D0/legacy\n");
 265                        goto done;
 266                }
 267
 268                /* NOTE:  dev->current_state becomes nonzero only here, and
 269                 * only for devices that support PCI PM.  Also, exiting
 270                 * PCI_D3 (but not PCI_D1 or PCI_D2) is allowed to reset
 271                 * some device state (e.g. as part of clock reinit).
 272                 */
 273                retval = pci_set_power_state(dev, PCI_D3hot);
 274                suspend_report_result(pci_set_power_state, retval);
 275                if (retval == 0) {
 276                        int wake = device_can_wakeup(&hcd->self.root_hub->dev);
 277
 278                        wake = wake && device_may_wakeup(hcd->self.controller);
 279
 280                        dev_dbg(hcd->self.controller, "--> PCI D3%s\n",
 281                                        wake ? "/wakeup" : "");
 282
 283                        /* Ignore these return values.  We rely on pci code to
 284                         * reject requests the hardware can't implement, rather
 285                         * than coding the same thing.
 286                         */
 287                        (void) pci_enable_wake(dev, PCI_D3hot, wake);
 288                        (void) pci_enable_wake(dev, PCI_D3cold, wake);
 289                } else {
 290                        dev_dbg(&dev->dev, "PCI D3 suspend fail, %d\n",
 291                                        retval);
 292                        (void) usb_hcd_pci_resume(dev);
 293                }
 294
 295        } else if (hcd->state != HC_STATE_HALT) {
 296                dev_dbg(hcd->self.controller, "hcd state %d; not suspended\n",
 297                        hcd->state);
 298                WARN_ON(1);
 299                retval = -EINVAL;
 300        }
 301
 302done:
 303        if (retval == 0) {
 304#ifdef CONFIG_PPC_PMAC
 305                /* Disable ASIC clocks for USB */
 306                if (machine_is(powermac)) {
 307                        struct device_node      *of_node;
 308
 309                        of_node = pci_device_to_OF_node(dev);
 310                        if (of_node)
 311                                pmac_call_feature(PMAC_FTR_USB_ENABLE,
 312                                                        of_node, 0, 0);
 313                }
 314#endif
 315        }
 316
 317        return retval;
 318}
 319EXPORT_SYMBOL_GPL(usb_hcd_pci_suspend);
 320
 321/**
 322 * usb_hcd_pci_resume - power management resume of a PCI-based HCD
 323 * @dev: USB Host Controller being resumed
 324 *
 325 * Store this function in the HCD's struct pci_driver as resume().
 326 */
 327int usb_hcd_pci_resume(struct pci_dev *dev)
 328{
 329        struct usb_hcd          *hcd;
 330        int                     retval;
 331
 332        hcd = pci_get_drvdata(dev);
 333        if (hcd->state != HC_STATE_SUSPENDED) {
 334                dev_dbg(hcd->self.controller,
 335                                "can't resume, not suspended!\n");
 336                return 0;
 337        }
 338
 339#ifdef CONFIG_PPC_PMAC
 340        /* Reenable ASIC clocks for USB */
 341        if (machine_is(powermac)) {
 342                struct device_node *of_node;
 343
 344                of_node = pci_device_to_OF_node(dev);
 345                if (of_node)
 346                        pmac_call_feature(PMAC_FTR_USB_ENABLE,
 347                                                of_node, 0, 1);
 348        }
 349#endif
 350
 351        /* NOTE:  chip docs cover clean "real suspend" cases (what Linux
 352         * calls "standby", "suspend to RAM", and so on).  There are also
 353         * dirty cases when swsusp fakes a suspend in "shutdown" mode.
 354         */
 355        if (dev->current_state != PCI_D0) {
 356#ifdef  DEBUG
 357                int     pci_pm;
 358                u16     pmcr;
 359
 360                pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM);
 361                pci_read_config_word(dev, pci_pm + PCI_PM_CTRL, &pmcr);
 362                pmcr &= PCI_PM_CTRL_STATE_MASK;
 363                if (pmcr) {
 364                        /* Clean case:  power to USB and to HC registers was
 365                         * maintained; remote wakeup is easy.
 366                         */
 367                        dev_dbg(hcd->self.controller, "resume from PCI D%d\n",
 368                                        pmcr);
 369                } else {
 370                        /* Clean:  HC lost Vcc power, D0 uninitialized
 371                         *   + Vaux may have preserved port and transceiver
 372                         *     state ... for remote wakeup from D3cold
 373                         *   + or not; HCD must reinit + re-enumerate
 374                         *
 375                         * Dirty: D0 semi-initialized cases with swsusp
 376                         *   + after BIOS init
 377                         *   + after Linux init (HCD statically linked)
 378                         */
 379                        dev_dbg(hcd->self.controller,
 380                                "PCI D0, from previous PCI D%d\n",
 381                                dev->current_state);
 382                }
 383#endif
 384                /* yes, ignore these results too... */
 385                (void) pci_enable_wake(dev, dev->current_state, 0);
 386                (void) pci_enable_wake(dev, PCI_D3cold, 0);
 387        } else {
 388                /* Same basic cases: clean (powered/not), dirty */
 389                dev_dbg(hcd->self.controller, "PCI legacy resume\n");
 390        }
 391
 392        /* NOTE:  the PCI API itself is asymmetric here.  We don't need to
 393         * pci_set_power_state(PCI_D0) since that's part of re-enabling;
 394         * but that won't re-enable bus mastering.  Yet pci_disable_device()
 395         * explicitly disables bus mastering...
 396         */
 397        retval = pci_enable_device(dev);
 398        if (retval < 0) {
 399                dev_err(hcd->self.controller,
 400                        "can't re-enable after resume, %d!\n", retval);
 401                return retval;
 402        }
 403        pci_set_master(dev);
 404        pci_restore_state(dev);
 405
 406        clear_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
 407
 408        if (hcd->driver->pci_resume) {
 409                retval = hcd->driver->pci_resume(hcd);
 410                if (retval) {
 411                        dev_err(hcd->self.controller,
 412                                "PCI post-resume error %d!\n", retval);
 413                        usb_hc_died(hcd);
 414                }
 415        }
 416
 417        return retval;
 418}
 419EXPORT_SYMBOL_GPL(usb_hcd_pci_resume);
 420
 421#endif  /* CONFIG_PM */
 422
 423/**
 424 * usb_hcd_pci_shutdown - shutdown host controller
 425 * @dev: USB Host Controller being shutdown
 426 */
 427void usb_hcd_pci_shutdown(struct pci_dev *dev)
 428{
 429        struct usb_hcd          *hcd;
 430
 431        hcd = pci_get_drvdata(dev);
 432        if (!hcd)
 433                return;
 434
 435        if (hcd->driver->shutdown)
 436                hcd->driver->shutdown(hcd);
 437}
 438EXPORT_SYMBOL_GPL(usb_hcd_pci_shutdown);
 439
 440
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