root/drivers/usb/host/uhci-pci.c
// SPDX-License-Identifier: GPL-2.0
/*
 * UHCI HCD (Host Controller Driver) PCI Bus Glue.
 *
 * Extracted from uhci-hcd.c:
 * Maintainer: Alan Stern <stern@rowland.harvard.edu>
 *
 * (C) Copyright 1999 Linus Torvalds
 * (C) Copyright 1999-2002 Johannes Erdfelt, johannes@erdfelt.com
 * (C) Copyright 1999 Randy Dunlap
 * (C) Copyright 1999 Georg Acher, acher@in.tum.de
 * (C) Copyright 1999 Deti Fliegl, deti@fliegl.de
 * (C) Copyright 1999 Thomas Sailer, sailer@ife.ee.ethz.ch
 * (C) Copyright 1999 Roman Weissgaerber, weissg@vienna.at
 * (C) Copyright 2000 Yggdrasil Computing, Inc. (port of new PCI interface
 *               support from usb-ohci.c by Adam Richter, adam@yggdrasil.com).
 * (C) Copyright 1999 Gregory P. Smith (from usb-ohci.c)
 * (C) Copyright 2004-2007 Alan Stern, stern@rowland.harvard.edu
 */

#include "pci-quirks.h"

/*
 * Make sure the controller is completely inactive, unable to
 * generate interrupts or do DMA.
 */
static void uhci_pci_reset_hc(struct uhci_hcd *uhci)
{
        uhci_reset_hc(to_pci_dev(uhci_dev(uhci)), uhci->io_addr);
}

/*
 * Initialize a controller that was newly discovered or has just been
 * resumed.  In either case we can't be sure of its previous state.
 *
 * Returns: 1 if the controller was reset, 0 otherwise.
 */
static int uhci_pci_check_and_reset_hc(struct uhci_hcd *uhci)
{
        return uhci_check_and_reset_hc(to_pci_dev(uhci_dev(uhci)),
                                uhci->io_addr);
}

/*
 * Store the basic register settings needed by the controller.
 * This function is called at the end of configure_hc in uhci-hcd.c.
 */
static void uhci_pci_configure_hc(struct uhci_hcd *uhci)
{
        struct pci_dev *pdev = to_pci_dev(uhci_dev(uhci));

        /* Enable PIRQ */
        pci_write_config_word(pdev, USBLEGSUP, USBLEGSUP_DEFAULT);

        /* Disable platform-specific non-PME# wakeup */
        if (pdev->vendor == PCI_VENDOR_ID_INTEL)
                pci_write_config_byte(pdev, USBRES_INTEL, 0);
}

static int uhci_pci_resume_detect_interrupts_are_broken(struct uhci_hcd *uhci)
{
        int port;

        switch (to_pci_dev(uhci_dev(uhci))->vendor) {
        default:
                break;

        case PCI_VENDOR_ID_GENESYS:
                /* Genesys Logic's GL880S controllers don't generate
                 * resume-detect interrupts.
                 */
                return 1;

        case PCI_VENDOR_ID_INTEL:
                /* Some of Intel's USB controllers have a bug that causes
                 * resume-detect interrupts if any port has an over-current
                 * condition.  To make matters worse, some motherboards
                 * hardwire unused USB ports' over-current inputs active!
                 * To prevent problems, we will not enable resume-detect
                 * interrupts if any ports are OC.
                 */
                for (port = 0; port < uhci->rh_numports; ++port) {
                        if (inw(uhci->io_addr + USBPORTSC1 + port * 2) &
                                        USBPORTSC_OC)
                                return 1;
                }
                break;
        }
        return 0;
}

static int uhci_pci_global_suspend_mode_is_broken(struct uhci_hcd *uhci)
{
        int port;
        const char *sys_info;
        static const char bad_Asus_board[] = "A7V8X";

        /* One of Asus's motherboards has a bug which causes it to
         * wake up immediately from suspend-to-RAM if any of the ports
         * are connected.  In such cases we will not set EGSM.
         */
        sys_info = dmi_get_system_info(DMI_BOARD_NAME);
        if (sys_info && !strcmp(sys_info, bad_Asus_board)) {
                for (port = 0; port < uhci->rh_numports; ++port) {
                        if (inw(uhci->io_addr + USBPORTSC1 + port * 2) &
                                        USBPORTSC_CCS)
                                return 1;
                }
        }

        return 0;
}

static int uhci_pci_init(struct usb_hcd *hcd)
{
        struct uhci_hcd *uhci = hcd_to_uhci(hcd);

        uhci->io_addr = (unsigned long) hcd->rsrc_start;

        uhci->rh_numports = uhci_count_ports(hcd);

        /*
         * Intel controllers report the OverCurrent bit active on.  VIA
         * and ZHAOXIN controllers report it active off, so we'll adjust
         * the bit value.  (It's not standardized in the UHCI spec.)
         */
        if (to_pci_dev(uhci_dev(uhci))->vendor == PCI_VENDOR_ID_VIA ||
                        to_pci_dev(uhci_dev(uhci))->vendor == PCI_VENDOR_ID_ZHAOXIN)
                uhci->oc_low = 1;

        /* HP's server management chip requires a longer port reset delay. */
        if (to_pci_dev(uhci_dev(uhci))->vendor == PCI_VENDOR_ID_HP)
                uhci->wait_for_hp = 1;

        /* Intel controllers use non-PME wakeup signalling */
        if (to_pci_dev(uhci_dev(uhci))->vendor == PCI_VENDOR_ID_INTEL)
                device_set_wakeup_capable(uhci_dev(uhci), true);

        /* Set up pointers to PCI-specific functions */
        uhci->reset_hc = uhci_pci_reset_hc;
        uhci->check_and_reset_hc = uhci_pci_check_and_reset_hc;
        uhci->configure_hc = uhci_pci_configure_hc;
        uhci->resume_detect_interrupts_are_broken =
                uhci_pci_resume_detect_interrupts_are_broken;
        uhci->global_suspend_mode_is_broken =
                uhci_pci_global_suspend_mode_is_broken;


        /* Kick BIOS off this hardware and reset if the controller
         * isn't already safely quiescent.
         */
        check_and_reset_hc(uhci);
        return 0;
}

/* Make sure the controller is quiescent and that we're not using it
 * any more.  This is mainly for the benefit of programs which, like kexec,
 * expect the hardware to be idle: not doing DMA or generating IRQs.
 *
 * This routine may be called in a damaged or failing kernel.  Hence we
 * do not acquire the spinlock before shutting down the controller.
 */
static void uhci_shutdown(struct pci_dev *pdev)
{
        struct usb_hcd *hcd = pci_get_drvdata(pdev);

        uhci_hc_died(hcd_to_uhci(hcd));
}

#ifdef CONFIG_PM

static int uhci_pci_resume(struct usb_hcd *hcd, pm_message_t state);

static int uhci_pci_suspend(struct usb_hcd *hcd, bool do_wakeup)
{
        struct uhci_hcd *uhci = hcd_to_uhci(hcd);
        struct pci_dev *pdev = to_pci_dev(uhci_dev(uhci));
        int rc = 0;

        dev_dbg(uhci_dev(uhci), "%s\n", __func__);

        spin_lock_irq(&uhci->lock);
        if (!HCD_HW_ACCESSIBLE(hcd) || uhci->dead)
                goto done_okay;         /* Already suspended or dead */

        /* All PCI host controllers are required to disable IRQ generation
         * at the source, so we must turn off PIRQ.
         */
        pci_write_config_word(pdev, USBLEGSUP, 0);
        clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);

        /* Enable platform-specific non-PME# wakeup */
        if (do_wakeup) {
                if (pdev->vendor == PCI_VENDOR_ID_INTEL)
                        pci_write_config_byte(pdev, USBRES_INTEL,
                                        USBPORT1EN | USBPORT2EN);
        }

done_okay:
        clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
        spin_unlock_irq(&uhci->lock);

        synchronize_irq(hcd->irq);

        /* Check for race with a wakeup request */
        if (do_wakeup && HCD_WAKEUP_PENDING(hcd)) {
                uhci_pci_resume(hcd, PMSG_SUSPEND);
                rc = -EBUSY;
        }
        return rc;
}

static int uhci_pci_resume(struct usb_hcd *hcd, pm_message_t msg)
{
        bool hibernated = (msg.event == PM_EVENT_RESTORE);
        struct uhci_hcd *uhci = hcd_to_uhci(hcd);

        dev_dbg(uhci_dev(uhci), "%s\n", __func__);

        /* Since we aren't in D3 any more, it's safe to set this flag
         * even if the controller was dead.
         */
        set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);

        spin_lock_irq(&uhci->lock);

        /* Make sure resume from hibernation re-enumerates everything */
        if (hibernated) {
                uhci->reset_hc(uhci);
                finish_reset(uhci);
        }

        /* The firmware may have changed the controller settings during
         * a system wakeup.  Check it and reconfigure to avoid problems.
         */
        else {
                check_and_reset_hc(uhci);
        }
        configure_hc(uhci);

        /* Tell the core if the controller had to be reset */
        if (uhci->rh_state == UHCI_RH_RESET)
                usb_root_hub_lost_power(hcd->self.root_hub);

        spin_unlock_irq(&uhci->lock);

        /* If interrupts don't work and remote wakeup is enabled then
         * the suspended root hub needs to be polled.
         */
        if (!uhci->RD_enable && hcd->self.root_hub->do_remote_wakeup)
                set_bit(HCD_FLAG_POLL_RH, &hcd->flags);

        /* Does the root hub have a port wakeup pending? */
        usb_hcd_poll_rh_status(hcd);
        return 0;
}

#endif

static const struct hc_driver uhci_driver = {
        .description =          hcd_name,
        .product_desc =         "UHCI Host Controller",
        .hcd_priv_size =        sizeof(struct uhci_hcd),

        /* Generic hardware linkage */
        .irq =                  uhci_irq,
        .flags =                HCD_DMA | HCD_USB11,

        /* Basic lifecycle operations */
        .reset =                uhci_pci_init,
        .start =                uhci_start,
#ifdef CONFIG_PM
        .pci_suspend =          uhci_pci_suspend,
        .pci_resume =           uhci_pci_resume,
        .bus_suspend =          uhci_rh_suspend,
        .bus_resume =           uhci_rh_resume,
#endif
        .stop =                 uhci_stop,

        .urb_enqueue =          uhci_urb_enqueue,
        .urb_dequeue =          uhci_urb_dequeue,

        .endpoint_disable =     uhci_hcd_endpoint_disable,
        .get_frame_number =     uhci_hcd_get_frame_number,

        .hub_status_data =      uhci_hub_status_data,
        .hub_control =          uhci_hub_control,
};

static const struct pci_device_id uhci_pci_ids[] = { {
        /* handle any USB UHCI controller */
        PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_USB_UHCI, ~0),
        }, { /* end: all zeroes */ }
};

MODULE_DEVICE_TABLE(pci, uhci_pci_ids);

static int uhci_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
{
        return usb_hcd_pci_probe(dev, &uhci_driver);
}

static struct pci_driver uhci_pci_driver = {
        .name =         hcd_name,
        .id_table =     uhci_pci_ids,

        .probe =        uhci_pci_probe,
        .remove =       usb_hcd_pci_remove,
        .shutdown =     uhci_shutdown,

#ifdef CONFIG_PM
        .driver =       {
                .pm =   &usb_hcd_pci_pm_ops
        },
#endif
};

MODULE_SOFTDEP("pre: ehci_pci");