hcd-pci.c

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/*
 * (C) Copyright David Brownell 2000-2002
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>

#include <asm/io.h>
#include <asm/irq.h>

#ifdef CONFIG_PPC_PMAC
#include <asm/machdep.h>
#include <asm/pmac_feature.h>
#include <asm/pci-bridge.h>
#include <asm/prom.h>
#endif

#include "usb.h"


/* PCI-based HCs are common, but plenty of non-PCI HCs are used too */

#ifdef CONFIG_PM_SLEEP

/* Coordinate handoffs between EHCI and companion controllers
 * during system resume
 */

static DEFINE_MUTEX(companions_mutex);

#define CL_UHCI     PCI_CLASS_SERIAL_USB_UHCI
#define CL_OHCI     PCI_CLASS_SERIAL_USB_OHCI
#define CL_EHCI     PCI_CLASS_SERIAL_USB_EHCI

enum companion_action {
    SET_HS_COMPANION, CLEAR_HS_COMPANION, WAIT_FOR_COMPANIONS
};

static void companion_common(struct pci_dev *pdev, struct usb_hcd *hcd,
        enum companion_action action)
{
    struct pci_dev      *companion;
    struct usb_hcd      *companion_hcd;
    unsigned int        slot = PCI_SLOT(pdev->devfn);

    /* Iterate through other PCI functions in the same slot.
     * If pdev is OHCI or UHCI then we are looking for EHCI, and
     * vice versa.
     */
    companion = NULL;
    for_each_pci_dev(companion) {
        if (companion->bus != pdev->bus ||
                PCI_SLOT(companion->devfn) != slot)
            continue;

        companion_hcd = pci_get_drvdata(companion);
        if (!companion_hcd)
            continue;

        /* For SET_HS_COMPANION, store a pointer to the EHCI bus in
         * the OHCI/UHCI companion bus structure.
         * For CLEAR_HS_COMPANION, clear the pointer to the EHCI bus
         * in the OHCI/UHCI companion bus structure.
         * For WAIT_FOR_COMPANIONS, wait until the OHCI/UHCI
         * companion controllers have fully resumed.
         */

        if ((pdev->class == CL_OHCI || pdev->class == CL_UHCI) &&
                companion->class == CL_EHCI) {
            /* action must be SET_HS_COMPANION */
            dev_dbg(&companion->dev, "HS companion for %s\n",
                    dev_name(&pdev->dev));
            hcd->self.hs_companion = &companion_hcd->self;

        } else if (pdev->class == CL_EHCI &&
                (companion->class == CL_OHCI ||
                companion->class == CL_UHCI)) {
            switch (action) {
            case SET_HS_COMPANION:
                dev_dbg(&pdev->dev, "HS companion for %s\n",
                        dev_name(&companion->dev));
                companion_hcd->self.hs_companion = &hcd->self;
                break;
            case CLEAR_HS_COMPANION:
                companion_hcd->self.hs_companion = NULL;
                break;
            case WAIT_FOR_COMPANIONS:
                device_pm_wait_for_dev(&pdev->dev,
                        &companion->dev);
                break;
            }
        }
    }
}

static void set_hs_companion(struct pci_dev *pdev, struct usb_hcd *hcd)
{
    mutex_lock(&companions_mutex);
    dev_set_drvdata(&pdev->dev, hcd);
    companion_common(pdev, hcd, SET_HS_COMPANION);
    mutex_unlock(&companions_mutex);
}

static void clear_hs_companion(struct pci_dev *pdev, struct usb_hcd *hcd)
{
    mutex_lock(&companions_mutex);
    dev_set_drvdata(&pdev->dev, NULL);

    /* If pdev is OHCI or UHCI, just clear its hs_companion pointer */
    if (pdev->class == CL_OHCI || pdev->class == CL_UHCI)
        hcd->self.hs_companion = NULL;

    /* Otherwise search for companion buses and clear their pointers */
    else
        companion_common(pdev, hcd, CLEAR_HS_COMPANION);
    mutex_unlock(&companions_mutex);
}

static void wait_for_companions(struct pci_dev *pdev, struct usb_hcd *hcd)
{
    /* Only EHCI controllers need to wait.
     * No locking is needed because a controller cannot be resumed
     * while one of its companions is getting unbound.
     */
    if (pdev->class == CL_EHCI)
        companion_common(pdev, hcd, WAIT_FOR_COMPANIONS);
}

#else /* !CONFIG_PM_SLEEP */

static inline void set_hs_companion(struct pci_dev *d, struct usb_hcd *h) {}
static inline void clear_hs_companion(struct pci_dev *d, struct usb_hcd *h) {}
static inline void wait_for_companions(struct pci_dev *d, struct usb_hcd *h) {}

#endif /* !CONFIG_PM_SLEEP */

/*-------------------------------------------------------------------------*/

/* configure so an HC device and id are always provided */
/* always called with process context; sleeping is OK */

int usb_hcd_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
{
    struct hc_driver    *driver;
    struct usb_hcd      *hcd;
    int         retval;

    if (usb_disabled())
        return -ENODEV;

    if (!id)
        return -EINVAL;
    driver = (struct hc_driver *)id->driver_data;
    if (!driver)
        return -EINVAL;

    if (pci_enable_device(dev) < 0)
        return -ENODEV;
    dev->current_state = PCI_D0;

    /* The xHCI driver supports MSI and MSI-X,
     * so don't fail if the BIOS doesn't provide a legacy IRQ.
     */
    if (!dev->irq && (driver->flags & HCD_MASK) != HCD_USB3) {
        dev_err(&dev->dev,
            "Found HC with no IRQ.  Check BIOS/PCI %s setup!\n",
            pci_name(dev));
        retval = -ENODEV;
        goto disable_pci;
    }

    hcd = usb_create_hcd(driver, &dev->dev, pci_name(dev));
    if (!hcd) {
        retval = -ENOMEM;
        goto disable_pci;
    }

    if (driver->flags & HCD_MEMORY) {
        /* EHCI, OHCI */
        hcd->rsrc_start = pci_resource_start(dev, 0);
        hcd->rsrc_len = pci_resource_len(dev, 0);
        if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len,
                driver->description)) {
            dev_dbg(&dev->dev, "controller already in use\n");
            retval = -EBUSY;
            goto clear_companion;
        }
        hcd->regs = ioremap_nocache(hcd->rsrc_start, hcd->rsrc_len);
        if (hcd->regs == NULL) {
            dev_dbg(&dev->dev, "error mapping memory\n");
            retval = -EFAULT;
            goto release_mem_region;
        }

    } else {
        /* UHCI */
        int region;

        for (region = 0; region < PCI_ROM_RESOURCE; region++) {
            if (!(pci_resource_flags(dev, region) &
                    IORESOURCE_IO))
                continue;

            hcd->rsrc_start = pci_resource_start(dev, region);
            hcd->rsrc_len = pci_resource_len(dev, region);
            if (request_region(hcd->rsrc_start, hcd->rsrc_len,
                    driver->description))
                break;
        }
        if (region == PCI_ROM_RESOURCE) {
            dev_dbg(&dev->dev, "no i/o regions available\n");
            retval = -EBUSY;
            goto clear_companion;
        }
    }

    pci_set_master(dev);

    retval = usb_add_hcd(hcd, dev->irq, IRQF_SHARED);
    if (retval != 0)
        goto unmap_registers;
    set_hs_companion(dev, hcd);

    if (pci_dev_run_wake(dev))
        pm_runtime_put_noidle(&dev->dev);
    return retval;

unmap_registers:
    if (driver->flags & HCD_MEMORY) {
        iounmap(hcd->regs);
release_mem_region:
        release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
    } else
        release_region(hcd->rsrc_start, hcd->rsrc_len);
clear_companion:
    clear_hs_companion(dev, hcd);
    usb_put_hcd(hcd);
disable_pci:
    pci_disable_device(dev);
    dev_err(&dev->dev, "init %s fail, %d\n", pci_name(dev), retval);
    return retval;
}
EXPORT_SYMBOL_GPL(usb_hcd_pci_probe);


/* may be called without controller electrically present */
/* may be called with controller, bus, and devices active */

void usb_hcd_pci_remove(struct pci_dev *dev)
{
    struct usb_hcd      *hcd;

    hcd = pci_get_drvdata(dev);
    if (!hcd)
        return;

    if (pci_dev_run_wake(dev))
        pm_runtime_get_noresume(&dev->dev);

    /* Fake an interrupt request in order to give the driver a chance
     * to test whether the controller hardware has been removed (e.g.,
     * cardbus physical eject).
     */
    local_irq_disable();
    usb_hcd_irq(0, hcd);
    local_irq_enable();

    usb_remove_hcd(hcd);
    if (hcd->driver->flags & HCD_MEMORY) {
        iounmap(hcd->regs);
        release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
    } else {
        release_region(hcd->rsrc_start, hcd->rsrc_len);
    }
    clear_hs_companion(dev, hcd);
    usb_put_hcd(hcd);
    pci_disable_device(dev);
}
EXPORT_SYMBOL_GPL(usb_hcd_pci_remove);

void usb_hcd_pci_shutdown(struct pci_dev *dev)
{
    struct usb_hcd      *hcd;

    hcd = pci_get_drvdata(dev);
    if (!hcd)
        return;

    if (test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags) &&
            hcd->driver->shutdown) {
        hcd->driver->shutdown(hcd);
        pci_disable_device(dev);
    }
}
EXPORT_SYMBOL_GPL(usb_hcd_pci_shutdown);

#ifdef  CONFIG_PM

#ifdef  CONFIG_PPC_PMAC
static void powermac_set_asic(struct pci_dev *pci_dev, int enable)
{
    /* Enanble or disable ASIC clocks for USB */
    if (machine_is(powermac)) {
        struct device_node  *of_node;

        of_node = pci_device_to_OF_node(pci_dev);
        if (of_node)
            pmac_call_feature(PMAC_FTR_USB_ENABLE,
                    of_node, 0, enable);
    }
}

#else

static inline void powermac_set_asic(struct pci_dev *pci_dev, int enable)
{}

#endif  /* CONFIG_PPC_PMAC */

static int check_root_hub_suspended(struct device *dev)
{
    struct pci_dev      *pci_dev = to_pci_dev(dev);
    struct usb_hcd      *hcd = pci_get_drvdata(pci_dev);

    if (HCD_RH_RUNNING(hcd)) {
        dev_warn(dev, "Root hub is not suspended\n");
        return -EBUSY;
    }
    if (hcd->shared_hcd) {
        hcd = hcd->shared_hcd;
        if (HCD_RH_RUNNING(hcd)) {
            dev_warn(dev, "Secondary root hub is not suspended\n");
            return -EBUSY;
        }
    }
    return 0;
}

#if defined(CONFIG_PM_SLEEP) || defined(CONFIG_PM_RUNTIME)
static int suspend_common(struct device *dev, bool do_wakeup)
{
    struct pci_dev      *pci_dev = to_pci_dev(dev);
    struct usb_hcd      *hcd = pci_get_drvdata(pci_dev);
    int         retval;

    /* Root hub suspend should have stopped all downstream traffic,
     * and all bus master traffic.  And done so for both the interface
     * and the stub usb_device (which we check here).  But maybe it
     * didn't; writing sysfs power/state files ignores such rules...
     */
    retval = check_root_hub_suspended(dev);
    if (retval)
        return retval;

    if (hcd->driver->pci_suspend && !HCD_DEAD(hcd)) {
        /* Optimization: Don't suspend if a root-hub wakeup is
         * pending and it would cause the HCD to wake up anyway.
         */
        if (do_wakeup && HCD_WAKEUP_PENDING(hcd))
            return -EBUSY;
        if (do_wakeup && hcd->shared_hcd &&
                HCD_WAKEUP_PENDING(hcd->shared_hcd))
            return -EBUSY;
        retval = hcd->driver->pci_suspend(hcd, do_wakeup);
        suspend_report_result(hcd->driver->pci_suspend, retval);

        /* Check again in case wakeup raced with pci_suspend */
        if ((retval == 0 && do_wakeup && HCD_WAKEUP_PENDING(hcd)) ||
                (retval == 0 && do_wakeup && hcd->shared_hcd &&
                 HCD_WAKEUP_PENDING(hcd->shared_hcd))) {
            if (hcd->driver->pci_resume)
                hcd->driver->pci_resume(hcd, false);
            retval = -EBUSY;
        }
        if (retval)
            return retval;
    }

    /* If MSI-X is enabled, the driver will have synchronized all vectors
     * in pci_suspend(). If MSI or legacy PCI is enabled, that will be
     * synchronized here.
     */
    if (!hcd->msix_enabled)
        synchronize_irq(pci_dev->irq);

    /* Downstream ports from this root hub should already be quiesced, so
     * there will be no DMA activity.  Now we can shut down the upstream
     * link (except maybe for PME# resume signaling).  We'll enter a
     * low power state during suspend_noirq, if the hardware allows.
     */
    pci_disable_device(pci_dev);
    return retval;
}

static int resume_common(struct device *dev, int event)
{
    struct pci_dev      *pci_dev = to_pci_dev(dev);
    struct usb_hcd      *hcd = pci_get_drvdata(pci_dev);
    int         retval;

    if (HCD_RH_RUNNING(hcd) ||
            (hcd->shared_hcd &&
             HCD_RH_RUNNING(hcd->shared_hcd))) {
        dev_dbg(dev, "can't resume, not suspended!\n");
        return 0;
    }

    retval = pci_enable_device(pci_dev);
    if (retval < 0) {
        dev_err(dev, "can't re-enable after resume, %d!\n", retval);
        return retval;
    }

    pci_set_master(pci_dev);

    if (hcd->driver->pci_resume && !HCD_DEAD(hcd)) {
        if (event != PM_EVENT_AUTO_RESUME)
            wait_for_companions(pci_dev, hcd);

        retval = hcd->driver->pci_resume(hcd,
                event == PM_EVENT_RESTORE);
        if (retval) {
            dev_err(dev, "PCI post-resume error %d!\n", retval);
            if (hcd->shared_hcd)
                usb_hc_died(hcd->shared_hcd);
            usb_hc_died(hcd);
        }
    }
    return retval;
}
#endif  /* SLEEP || RUNTIME */

#ifdef  CONFIG_PM_SLEEP

static int hcd_pci_suspend(struct device *dev)
{
    return suspend_common(dev, device_may_wakeup(dev));
}

static int hcd_pci_suspend_noirq(struct device *dev)
{
    struct pci_dev      *pci_dev = to_pci_dev(dev);
    struct usb_hcd      *hcd = pci_get_drvdata(pci_dev);
    int         retval;

    retval = check_root_hub_suspended(dev);
    if (retval)
        return retval;

    pci_save_state(pci_dev);

    /* If the root hub is dead rather than suspended, disallow remote
     * wakeup.  usb_hc_died() should ensure that both hosts are marked as
     * dying, so we only need to check the primary roothub.
     */
    if (HCD_DEAD(hcd))
        device_set_wakeup_enable(dev, 0);
    dev_dbg(dev, "wakeup: %d\n", device_may_wakeup(dev));

    /* Possibly enable remote wakeup,
     * choose the appropriate low-power state, and go to that state.
     */
    retval = pci_prepare_to_sleep(pci_dev);
    if (retval == -EIO) {       /* Low-power not supported */
        dev_dbg(dev, "--> PCI D0 legacy\n");
        retval = 0;
    } else if (retval == 0) {
        dev_dbg(dev, "--> PCI %s\n",
                pci_power_name(pci_dev->current_state));
    } else {
        suspend_report_result(pci_prepare_to_sleep, retval);
        return retval;
    }

    powermac_set_asic(pci_dev, 0);
    return retval;
}

static int hcd_pci_resume_noirq(struct device *dev)
{
    struct pci_dev      *pci_dev = to_pci_dev(dev);

    powermac_set_asic(pci_dev, 1);

    /* Go back to D0 and disable remote wakeup */
    pci_back_from_sleep(pci_dev);
    return 0;
}

static int hcd_pci_resume(struct device *dev)
{
    return resume_common(dev, PM_EVENT_RESUME);
}

static int hcd_pci_restore(struct device *dev)
{
    return resume_common(dev, PM_EVENT_RESTORE);
}

#else

#define hcd_pci_suspend     NULL
#define hcd_pci_suspend_noirq   NULL
#define hcd_pci_resume_noirq    NULL
#define hcd_pci_resume      NULL
#define hcd_pci_restore     NULL

#endif  /* CONFIG_PM_SLEEP */

#ifdef  CONFIG_PM_RUNTIME

static int hcd_pci_runtime_suspend(struct device *dev)
{
    int retval;

    retval = suspend_common(dev, true);
    if (retval == 0)
        powermac_set_asic(to_pci_dev(dev), 0);
    dev_dbg(dev, "hcd_pci_runtime_suspend: %d\n", retval);
    return retval;
}

static int hcd_pci_runtime_resume(struct device *dev)
{
    int retval;

    powermac_set_asic(to_pci_dev(dev), 1);
    retval = resume_common(dev, PM_EVENT_AUTO_RESUME);
    dev_dbg(dev, "hcd_pci_runtime_resume: %d\n", retval);
    return retval;
}

#else

#define hcd_pci_runtime_suspend NULL
#define hcd_pci_runtime_resume  NULL

#endif  /* CONFIG_PM_RUNTIME */

const struct dev_pm_ops usb_hcd_pci_pm_ops = {
    .suspend    = hcd_pci_suspend,
    .suspend_noirq  = hcd_pci_suspend_noirq,
    .resume_noirq   = hcd_pci_resume_noirq,
    .resume     = hcd_pci_resume,
    .freeze     = check_root_hub_suspended,
    .freeze_noirq   = check_root_hub_suspended,
    .thaw_noirq = NULL,
    .thaw       = NULL,
    .poweroff   = hcd_pci_suspend,
    .poweroff_noirq = hcd_pci_suspend_noirq,
    .restore_noirq  = hcd_pci_resume_noirq,
    .restore    = hcd_pci_restore,
    .runtime_suspend = hcd_pci_runtime_suspend,
    .runtime_resume = hcd_pci_runtime_resume,
};
EXPORT_SYMBOL_GPL(usb_hcd_pci_pm_ops);

#endif  /* CONFIG_PM */