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 0aa2832dd0 (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>
This commit is contained in:
Alan Stern
2014-05-01 15:21:42 -04:00
committed by Greg Kroah-Hartman
parent 4dd7aa0f3c
commit c1db30a2a7
3 changed files with 21 additions and 0 deletions

View File

@@ -405,6 +405,8 @@ struct ohci_hcd {
#define OHCI_QUIRK_HUB_POWER 0x100 /* distrust firmware power/oc setup */
#define OHCI_QUIRK_AMD_PLL 0x200 /* AMD PLL quirk*/
#define OHCI_QUIRK_AMD_PREFETCH 0x400 /* pre-fetch for ISO transfer */
#define OHCI_QUIRK_GLOBAL_SUSPEND 0x800 /* must suspend ports */
// there are also chip quirks/bugs in init logic
struct work_struct nec_work; /* Worker for NEC quirk */