On 11.05.2015 17:44, Ralf Jung wrote:
> Hi,
>
>> Ok, xhci is reset in resume in your case (indicated by the "root hub lost power or was reset" messages)
>> That patch adds an additional check that ensures there was some event before resuming the roothub.
>>
>> Could you try out the following and see if it helps? If the event is lost/cleared during reset
>> then this change should work.
>
> Sure. What version is this patch against? I did "patch -p1" with
> v4.1-rc2 checked out, and all three hunks fail.
>
Attached a testpatch based on 4.1-rc2
>> Can you try with auto-pm disabled for PCI xHCI host?
>>
>> # echo 'on' | tee /sys/bus/pci/devices/*/power/control
>
> I'll also try the PM settings mentioned by baolu. In fact, he reminded
> me that I added the following udev rule to save some power (and powertop
> got happy ;-):
>
> ACTION=="add", SUBSYSTEM=="pci", ATTR{power/control}="auto"
>
> Sorry that I forgot to mention this.
No worries, we need to get the usb3 drive detected even if the controller is in runtime suspend.
-Mathias
>From 7e0326dd33ab53edef694cb2ec0a4d6ec46b9c97 Mon Sep 17 00:00:00 2001
From: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
Date: Tue, 12 May 2015 13:40:34 +0300
Subject: [PATCH] xhci: check if roothubs need to be resumed early in xhci
resume
Testpatch for Ralf Jung to check if we got a pending event interrupt
early when resuming the host, and make sure resume the roothubs in that case.
A theory is that the cases we need to re-initialize the xhci host in resume we
will lose the event interrupt, and refuse to resume the roothubs as there are
no pending event to handle.
Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
---
drivers/usb/host/xhci.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index ec8ac16..2e0d6ba 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -982,6 +982,7 @@ int xhci_resume(struct xhci_hcd *xhci, bool hibernated)
struct usb_hcd *secondary_hcd;
int retval = 0;
bool comp_timer_running = false;
+ int resume_hubs;
/* Wait a bit if either of the roothubs need to settle from the
* transition into bus suspend.
@@ -1017,6 +1018,8 @@ int xhci_resume(struct xhci_hcd *xhci, bool hibernated)
temp = readl(&xhci->op_regs->status);
}
+ resume_hubs = readl(&xhci->op_regs->status) & STS_EINT;
+
/* If restore operation fails, re-initialize the HC during resume */
if ((temp & STS_SRE) || hibernated) {
@@ -1097,7 +1100,7 @@ int xhci_resume(struct xhci_hcd *xhci, bool hibernated)
if (retval == 0) {
/* Resume root hubs only when have pending events. */
status = readl(&xhci->op_regs->status);
- if (status & STS_EINT) {
+ if (status & STS_EINT || resume_hubs) {
usb_hcd_resume_root_hub(hcd);
usb_hcd_resume_root_hub(xhci->shared_hcd);
}
--
1.8.3.2
