diff options
| author | Alan Stern <stern@rowland.harvard.edu> | 2014-05-01 15:21:42 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-05-03 17:58:46 -0400 |
| commit | c1db30a2a79eb59997b13b8cabf2a50bea9f04e1 (patch) | |
| tree | b026621ae7b87879322513c4b4fc19dee2a7a5bb /drivers/usb/host/ohci-hub.c | |
| parent | 4dd7aa0f3c8ade14da682311cdc0e1298226763e (diff) | |
USB: OHCI: fix problem with global suspend on ATI controllers
Some OHCI controllers from ATI/AMD seem to have difficulty with
"global" USB suspend, that is, suspending an entire USB bus without
setting the suspend feature for each port connected to a device. When
we try to resume the child devices, the controller gives timeout
errors on the unsuspended ports, requiring resets, and can even cause
ohci-hcd to hang; see
http://marc.info/?l=linux-usb&m=139514332820398&w=2
and the following messages.
This patch fixes the problem by adding a new quirk flag to ohci-hcd.
The flag causes the ohci_rh_suspend() routine to suspend each
unsuspended, enabled port before suspending the root hub. This
effectively converts the "global" suspend to an ordinary root-hub
suspend. There is no need to unsuspend these ports when the root hub
is resumed, because the child devices will be resumed anyway in the
course of a normal system resume ("global" suspend is never used for
runtime PM).
This patch should be applied to all stable kernels which include
commit 0aa2832dd0d9 (USB: use "global suspend" for system sleep on
USB-2 buses) or a backported version thereof.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Peter Münster <pmlists@free.fr>
Tested-by: Peter Münster <pmlists@free.fr>
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/host/ohci-hub.c')
| -rw-r--r-- | drivers/usb/host/ohci-hub.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/drivers/usb/host/ohci-hub.c b/drivers/usb/host/ohci-hub.c index c81c8721cc5a..cd871b895013 100644 --- a/drivers/usb/host/ohci-hub.c +++ b/drivers/usb/host/ohci-hub.c @@ -90,6 +90,24 @@ __acquires(ohci->lock) dl_done_list (ohci); finish_unlinks (ohci, ohci_frame_no(ohci)); + /* + * Some controllers don't handle "global" suspend properly if + * there are unsuspended ports. For these controllers, put all + * the enabled ports into suspend before suspending the root hub. + */ + if (ohci->flags & OHCI_QUIRK_GLOBAL_SUSPEND) { + __hc32 __iomem *portstat = ohci->regs->roothub.portstatus; + int i; + unsigned temp; + + for (i = 0; i < ohci->num_ports; (++i, ++portstat)) { + temp = ohci_readl(ohci, portstat); + if ((temp & (RH_PS_PES | RH_PS_PSS)) == + RH_PS_PES) + ohci_writel(ohci, RH_PS_PSS, portstat); + } + } + /* maybe resume can wake root hub */ if (ohci_to_hcd(ohci)->self.root_hub->do_remote_wakeup || autostop) { ohci->hc_control |= OHCI_CTRL_RWE; |