diff options
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/host/uhci-hcd.c | 74 | ||||
| -rw-r--r-- | drivers/usb/host/uhci-hcd.h | 5 |
2 files changed, 61 insertions, 18 deletions
diff --git a/drivers/usb/host/uhci-hcd.c b/drivers/usb/host/uhci-hcd.c index d3e0d8aa398..3a7bfe7a887 100644 --- a/drivers/usb/host/uhci-hcd.c +++ b/drivers/usb/host/uhci-hcd.c @@ -234,7 +234,7 @@ static int resume_detect_interrupts_are_broken(struct uhci_hcd *uhci) return 0; } -static int remote_wakeup_is_broken(struct uhci_hcd *uhci) +static int global_suspend_mode_is_broken(struct uhci_hcd *uhci) { int port; const char *sys_info; @@ -261,27 +261,60 @@ __releases(uhci->lock) __acquires(uhci->lock) { int auto_stop; - int int_enable, egsm_enable; + int int_enable, egsm_enable, wakeup_enable; struct usb_device *rhdev = uhci_to_hcd(uhci)->self.root_hub; auto_stop = (new_state == UHCI_RH_AUTO_STOPPED); dev_dbg(&rhdev->dev, "%s%s\n", __func__, (auto_stop ? " (auto-stop)" : "")); - /* Enable resume-detect interrupts if they work. - * Then enter Global Suspend mode if _it_ works, still configured. + /* Start off by assuming Resume-Detect interrupts and EGSM work + * and that remote wakeups should be enabled. */ egsm_enable = USBCMD_EGSM; - uhci->working_RD = 1; + uhci->RD_enable = 1; int_enable = USBINTR_RESUME; - if (remote_wakeup_is_broken(uhci)) - egsm_enable = 0; - if (resume_detect_interrupts_are_broken(uhci) || !egsm_enable || + wakeup_enable = 1; + + /* In auto-stop mode wakeups must always be detected, but + * Resume-Detect interrupts may be prohibited. (In the absence + * of CONFIG_PM, they are always disallowed.) + */ + if (auto_stop) { + if (!device_may_wakeup(&rhdev->dev)) + int_enable = 0; + + /* In bus-suspend mode wakeups may be disabled, but if they are + * allowed then so are Resume-Detect interrupts. + */ + } else { #ifdef CONFIG_PM - (!auto_stop && !rhdev->do_remote_wakeup) || + if (!rhdev->do_remote_wakeup) + wakeup_enable = 0; #endif - (auto_stop && !device_may_wakeup(&rhdev->dev))) - uhci->working_RD = int_enable = 0; + } + + /* EGSM causes the root hub to echo a 'K' signal (resume) out any + * port which requests a remote wakeup. According to the USB spec, + * every hub is supposed to do this. But if we are ignoring + * remote-wakeup requests anyway then there's no point to it. + * We also shouldn't enable EGSM if it's broken. + */ + if (!wakeup_enable || global_suspend_mode_is_broken(uhci)) + egsm_enable = 0; + + /* If we're ignoring wakeup events then there's no reason to + * enable Resume-Detect interrupts. We also shouldn't enable + * them if they are broken or disallowed. + * + * This logic may lead us to enabling RD but not EGSM. The UHCI + * spec foolishly says that RD works only when EGSM is on, but + * there's no harm in enabling it anyway -- perhaps some chips + * will implement it! + */ + if (!wakeup_enable || resume_detect_interrupts_are_broken(uhci) || + !int_enable) + uhci->RD_enable = int_enable = 0; outw(int_enable, uhci->io_addr + USBINTR); outw(egsm_enable | USBCMD_CF, uhci->io_addr + USBCMD); @@ -308,7 +341,11 @@ __acquires(uhci->lock) uhci->rh_state = new_state; uhci->is_stopped = UHCI_IS_STOPPED; - uhci_to_hcd(uhci)->poll_rh = !int_enable; + + /* If interrupts don't work and remote wakeup is enabled then + * the suspended root hub needs to be polled. + */ + uhci_to_hcd(uhci)->poll_rh = (!int_enable && wakeup_enable); uhci_scan_schedule(uhci); uhci_fsbr_off(uhci); @@ -344,9 +381,12 @@ __acquires(uhci->lock) * for 20 ms. */ if (uhci->rh_state == UHCI_RH_SUSPENDED) { + unsigned egsm; + + /* Keep EGSM on if it was set before */ + egsm = inw(uhci->io_addr + USBCMD) & USBCMD_EGSM; uhci->rh_state = UHCI_RH_RESUMING; - outw(USBCMD_FGR | USBCMD_EGSM | USBCMD_CF, - uhci->io_addr + USBCMD); + outw(USBCMD_FGR | USBCMD_CF | egsm, uhci->io_addr + USBCMD); spin_unlock_irq(&uhci->lock); msleep(20); spin_lock_irq(&uhci->lock); @@ -801,8 +841,10 @@ static int uhci_pci_resume(struct usb_hcd *hcd) spin_unlock_irq(&uhci->lock); - if (!uhci->working_RD) { - /* Suspended root hub needs to be polled */ + /* 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) { hcd->poll_rh = 1; usb_hcd_poll_rh_status(hcd); } diff --git a/drivers/usb/host/uhci-hcd.h b/drivers/usb/host/uhci-hcd.h index 340d6ed3e6e..7d01c5677f9 100644 --- a/drivers/usb/host/uhci-hcd.h +++ b/drivers/usb/host/uhci-hcd.h @@ -400,8 +400,9 @@ struct uhci_hcd { unsigned int scan_in_progress:1; /* Schedule scan is running */ unsigned int need_rescan:1; /* Redo the schedule scan */ unsigned int dead:1; /* Controller has died */ - unsigned int working_RD:1; /* Suspended root hub doesn't - need to be polled */ + unsigned int RD_enable:1; /* Suspended root hub with + Resume-Detect interrupts + enabled */ unsigned int is_initialized:1; /* Data structure is usable */ unsigned int fsbr_is_on:1; /* FSBR is turned on */ unsigned int fsbr_is_wanted:1; /* Does any URB want FSBR? */ |