diff options
Diffstat (limited to 'drivers/usb/host/ehci-hcd.c')
| -rw-r--r-- | drivers/usb/host/ehci-hcd.c | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c index c49fc1e7895..e6823a0cf64 100644 --- a/drivers/usb/host/ehci-hcd.c +++ b/drivers/usb/host/ehci-hcd.c @@ -1242,6 +1242,95 @@ static int ehci_get_frame (struct usb_hcd *hcd) } /*-------------------------------------------------------------------------*/ + +#ifdef CONFIG_PM + +/* suspend/resume, section 4.3 */ + +/* These routines handle the generic parts of controller suspend/resume */ + +static int __maybe_unused ehci_suspend(struct usb_hcd *hcd, bool do_wakeup) +{ + struct ehci_hcd *ehci = hcd_to_ehci(hcd); + + if (time_before(jiffies, ehci->next_statechange)) + msleep(10); + + /* + * Root hub was already suspended. Disable IRQ emission and + * mark HW unaccessible. The PM and USB cores make sure that + * the root hub is either suspended or stopped. + */ + ehci_prepare_ports_for_controller_suspend(ehci, do_wakeup); + + spin_lock_irq(&ehci->lock); + ehci_writel(ehci, 0, &ehci->regs->intr_enable); + (void) ehci_readl(ehci, &ehci->regs->intr_enable); + + clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags); + spin_unlock_irq(&ehci->lock); + + return 0; +} + +/* Returns 0 if power was preserved, 1 if power was lost */ +static int __maybe_unused ehci_resume(struct usb_hcd *hcd, bool hibernated) +{ + struct ehci_hcd *ehci = hcd_to_ehci(hcd); + + if (time_before(jiffies, ehci->next_statechange)) + msleep(100); + + /* Mark hardware accessible again as we are back to full power by now */ + set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags); + + /* + * If CF is still set and we aren't resuming from hibernation + * then we maintained suspend power. + * Just undo the effect of ehci_suspend(). + */ + if (ehci_readl(ehci, &ehci->regs->configured_flag) == FLAG_CF && + !hibernated) { + int mask = INTR_MASK; + + ehci_prepare_ports_for_controller_resume(ehci); + if (!hcd->self.root_hub->do_remote_wakeup) + mask &= ~STS_PCD; + ehci_writel(ehci, mask, &ehci->regs->intr_enable); + ehci_readl(ehci, &ehci->regs->intr_enable); + return 0; + } + + /* + * Else reset, to cope with power loss or resume from hibernation + * having let the firmware kick in during reboot. + */ + usb_root_hub_lost_power(hcd->self.root_hub); + (void) ehci_halt(ehci); + (void) ehci_reset(ehci); + + /* emptying the schedule aborts any urbs */ + spin_lock_irq(&ehci->lock); + if (ehci->reclaim) + end_unlink_async(ehci); + ehci_work(ehci); + spin_unlock_irq(&ehci->lock); + + ehci_writel(ehci, ehci->command, &ehci->regs->command); + ehci_writel(ehci, FLAG_CF, &ehci->regs->configured_flag); + ehci_readl(ehci, &ehci->regs->command); /* unblock posted writes */ + + /* here we "know" root ports should always stay powered */ + ehci_port_power(ehci, 1); + + ehci->rh_state = EHCI_RH_SUSPENDED; + return 1; +} + +#endif + +/*-------------------------------------------------------------------------*/ + /* * The EHCI in ChipIdea HDRC cannot be a separate module or device, * because its registers (and irq) are shared between host/gadget/otg |