[PATCH 3.13.y-ckt 15/60] xhci: report U3 when link is in resume state

[Kamal Mostafa]

3.13.11-ckt26 -stable review patch.  If anyone has any objections, please let 
me know.

--

From: Zhuang Jin Can 

commit 243292a2ad3dc365849b820a64868927168894ac upstream.

xhci_hub_report_usb3_link_state() returns pls as U0 when the link
is in resume state, and this causes usb core to think the link is in
U0 while actually it's in resume state. When usb core transfers
control request on the link, it fails with TRB error as the link
is not ready for transfer.

To fix the issue, report U3 when the link is in resume state, thus
usb core knows the link it's not ready for transfer.

Signed-off-by: Zhuang Jin Can 
Signed-off-by: Mathias Nyman 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Kamal Mostafa 
---
 drivers/usb/host/xhci-hub.c | 7 +--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index 9b69daf..d2d82de 100644
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -480,10 +480,13 @@ static void xhci_hub_report_usb3_link_state(struct 
xhci_hcd *xhci,
u32 pls = status_reg & PORT_PLS_MASK;
 
/* resume state is a xHCI internal state.
-* Do not report it to usb core.
+* Do not report it to usb core, instead, pretend to be U3,
+* thus usb core knows it's not ready for transfer
 */
-   if (pls == XDEV_RESUME)
+   if (pls == XDEV_RESUME) {
+   *status |= USB_SS_PORT_LS_U3;
return;
+   }
 
/* When the CAS bit is set then warm reset
 * should be performed on port
-- 
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[PATCH 3.13.y-ckt 15/60] xhci: report U3 when link is in resume state

[Kamal Mostafa]

3.13.11-ckt26 -stable review patch.  If anyone has any objections, please let 
me know.

--

From: Zhuang Jin Can 

commit 243292a2ad3dc365849b820a64868927168894ac upstream.

xhci_hub_report_usb3_link_state() returns pls as U0 when the link
is in resume state, and this causes usb core to think the link is in
U0 while actually it's in resume state. When usb core transfers
control request on the link, it fails with TRB error as the link
is not ready for transfer.

To fix the issue, report U3 when the link is in resume state, thus
usb core knows the link it's not ready for transfer.

Signed-off-by: Zhuang Jin Can 
Signed-off-by: Mathias Nyman 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Kamal Mostafa 
---
 drivers/usb/host/xhci-hub.c | 7 +--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index 9b69daf..d2d82de 100644
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -480,10 +480,13 @@ static void xhci_hub_report_usb3_link_state(struct 
xhci_hcd *xhci,
u32 pls = status_reg & PORT_PLS_MASK;
 
/* resume state is a xHCI internal state.
-* Do not report it to usb core.
+* Do not report it to usb core, instead, pretend to be U3,
+* thus usb core knows it's not ready for transfer
 */
-   if (pls == XDEV_RESUME)
+   if (pls == XDEV_RESUME) {
+   *status |= USB_SS_PORT_LS_U3;
return;
+   }
 
/* When the CAS bit is set then warm reset
 * should be performed on port
-- 
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/