aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/usb/core
diff options
context:
space:
mode:
authorJulius Werner <jwerner@chromium.org>2013-10-15 17:45:00 -0700
committerBen Hutchings <ben@decadent.org.uk>2014-01-03 04:33:14 +0000
commit40c8b4ee658b72eb8c4627c0620a5bb44427d869 (patch)
tree3aa2ee4d2e042cb412bee35e535f8f6851a03a1e /drivers/usb/core
parent7e6337b694966dd7d3b9d904c830b48a4e6a80a6 (diff)
downloadkernel_samsung_smdk4412-40c8b4ee658b72eb8c4627c0620a5bb44427d869.zip
kernel_samsung_smdk4412-40c8b4ee658b72eb8c4627c0620a5bb44427d869.tar.gz
kernel_samsung_smdk4412-40c8b4ee658b72eb8c4627c0620a5bb44427d869.tar.bz2
usb: hub: Clear Port Reset Change during init/resume
commit e92aee330837e4911553761490a8fb843f2053a6 upstream. This patch adds the Port Reset Change flag to the set of bits that are preemptively cleared on init/resume of a hub. In theory this bit should never be set unexpectedly... in practice it can still happen if BIOS, SMM or ACPI code plays around with USB devices without cleaning up correctly. This is especially dangerous for XHCI root hubs, which don't generate any more Port Status Change Events until all change bits are cleared, so this is a good precaution to have (similar to how it's already done for the Warm Port Reset Change flag). Signed-off-by: Julius Werner <jwerner@chromium.org> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [bwh: Backported to 3.2: - Adjust context - s/usb_clear_port_feature/clear_port_feature/] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'drivers/usb/core')
-rw-r--r--drivers/usb/core/hub.c5
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 70987fb..a619793 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -900,6 +900,11 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
clear_port_feature(hub->hdev, port1,
USB_PORT_FEAT_C_PORT_LINK_STATE);
}
+ if (portchange & USB_PORT_STAT_C_RESET) {
+ need_debounce_delay = true;
+ clear_port_feature(hub->hdev, port1,
+ USB_PORT_FEAT_C_RESET);
+ }
if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
hub_is_superspeed(hub->hdev)) {