[PATCH] USB: hcd: Mark secondary HCD as dead if the primary one died

From: Rafael J. Wysocki
Date: Tue Jul 25 2017 - 18:06:54 EST


From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

Make usb_hc_died() clear the HCD_FLAG_RH_RUNNING flag for the shared
HCD and set HCD_FLAG_DEAD for it, in analogy with what is done for
the primary one.

Among other thigs, this prevents check_root_hub_suspended() from
returning -EBUSY for dead HCDs which helps to work around system
suspend issues in some situations.

This actually fixes occasional suspend failures on one of my test
machines.

Suggested-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
drivers/usb/core/hcd.c | 2 ++
1 file changed, 2 insertions(+)

Index: linux-pm/drivers/usb/core/hcd.c
===================================================================
--- linux-pm.orig/drivers/usb/core/hcd.c
+++ linux-pm/drivers/usb/core/hcd.c
@@ -2485,6 +2485,8 @@ void usb_hc_died (struct usb_hcd *hcd)
}
if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
hcd = hcd->shared_hcd;
+ clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
+ set_bit(HCD_FLAG_DEAD, &hcd->flags);
if (hcd->rh_registered) {
clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);