diff options
Diffstat (limited to 'usb/usb-controller-resume-should-check-the-root-hub.patch')
| -rw-r--r-- | usb/usb-controller-resume-should-check-the-root-hub.patch | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/usb/usb-controller-resume-should-check-the-root-hub.patch b/usb/usb-controller-resume-should-check-the-root-hub.patch new file mode 100644 index 00000000000000..c0fc5896cf2aa1 --- /dev/null +++ b/usb/usb-controller-resume-should-check-the-root-hub.patch @@ -0,0 +1,95 @@ +From stern@rowland.harvard.edu Wed Jul 7 14:55:34 2010 +From: Alan Stern <stern@rowland.harvard.edu> +Date: Fri, 25 Jun 2010 14:02:24 -0400 (EDT) +Subject: USB: controller resume should check the root hub +To: Greg KH <greg@kroah.com> +Message-ID: <Pine.LNX.4.44L0.1006251244030.1604-100000@iolanthe.rowland.org> + + +This patch (as1394) adds code to ehci-hcd, ohci-hcd, and uhci-hcd for +automatically resuming the root hub when the controller is resumed, if +the root hub has a wakeup request pending on some port. + +During resume from system sleep this doesn't matter, because the root +hubs will naturally be resumed along with every other device in the +system. However it _will_ matter for runtime PM: If the controller is +suspended and a remote wakeup request is received then the controller +will autoresume, but we need to ensure that the root hub also +autoresumes. Otherwise the wakeup request would be ignored, the +controller would go back to sleep, and the cycle would repeat a large +number of times (I saw this happen before the patch was written). + +Signed-off-by: Alan Stern <stern@rowland.harvard.edu> +Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> + +--- + drivers/usb/host/ehci-hub.c | 4 ++++ + drivers/usb/host/ohci-hub.c | 7 ++++++- + drivers/usb/host/uhci-hcd.c | 7 ++++--- + drivers/usb/host/uhci-hub.c | 2 +- + 4 files changed, 15 insertions(+), 5 deletions(-) + +--- a/drivers/usb/host/ehci-hub.c ++++ b/drivers/usb/host/ehci-hub.c +@@ -166,6 +166,10 @@ static void ehci_adjust_port_wakeup_flag + ehci_writel(ehci, temp | HOSTPC_PHCD, hostpc_reg); + } + } ++ ++ /* Does the root hub have a port wakeup pending? */ ++ if (!suspending && (ehci_readl(ehci, &ehci->regs->status) & STS_PCD)) ++ usb_hcd_resume_root_hub(ehci_to_hcd(ehci)); + } + + static int ehci_bus_suspend (struct usb_hcd *hcd) +--- a/drivers/usb/host/ohci-hub.c ++++ b/drivers/usb/host/ohci-hub.c +@@ -355,6 +355,11 @@ static void ohci_finish_controller_resum + ohci_readl(ohci, &ohci->regs->intrenable); + msleep(20); + } ++ ++ /* Does the root hub have a port wakeup pending? */ ++ if (ohci_readl(ohci, &ohci->regs->intrstatus) & ++ (OHCI_INTR_RD | OHCI_INTR_RHSC)) ++ usb_hcd_resume_root_hub(hcd); + } + + /* Carry out polling-, autostop-, and autoresume-related state changes */ +@@ -364,7 +369,7 @@ static int ohci_root_hub_state_changes(s + int poll_rh = 1; + int rhsc_enable; + +- /* Some broken controllers never turn off RHCS in the interrupt ++ /* Some broken controllers never turn off RHSC in the interrupt + * status register. For their sake we won't re-enable RHSC + * interrupts if the interrupt bit is already active. + */ +--- a/drivers/usb/host/uhci-hcd.c ++++ b/drivers/usb/host/uhci-hcd.c +@@ -862,10 +862,11 @@ static int uhci_pci_resume(struct usb_hc + /* 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) { ++ if (!uhci->RD_enable && hcd->self.root_hub->do_remote_wakeup) + set_bit(HCD_FLAG_POLL_RH, &hcd->flags); +- usb_hcd_poll_rh_status(hcd); +- } ++ ++ /* Does the root hub have a port wakeup pending? */ ++ usb_hcd_poll_rh_status(hcd); + return 0; + } + #endif +--- a/drivers/usb/host/uhci-hub.c ++++ b/drivers/usb/host/uhci-hub.c +@@ -200,7 +200,7 @@ static int uhci_hub_status_data(struct u + case UHCI_RH_SUSPENDING: + case UHCI_RH_SUSPENDED: + /* if port change, ask to be resumed */ +- if (status) ++ if (status || uhci->resuming_ports) + usb_hcd_resume_root_hub(hcd); + break; + |