[PATCH 1/1] usb: xhci: set RWE only for remote wakeup capable devices

From: Lu Baolu
Date: Thu Jan 12 2017 - 03:54:37 EST


Xhci spec requires in section 4.23.5.1.1.1 that the RWE bit of USB2
PORTPMSC register should only set for remote wakeup capble devices.

This was suggested by Mathias in the following discussion thread.
http://marc.info/?l=linux-usb&m=148154757829677&w=2

Suggested-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
---
drivers/usb/host/xhci.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 0c8deb9..d887e09 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -4191,7 +4191,9 @@ int xhci_set_usb2_hardware_lpm(struct usb_hcd *hcd,
}

pm_val &= ~PORT_HIRD_MASK;
- pm_val |= PORT_HIRD(hird) | PORT_RWE | PORT_L1DS(udev->slot_id);
+ pm_val |= PORT_HIRD(hird) | PORT_L1DS(udev->slot_id);
+ if (udev->do_remote_wakeup)
+ pm_val |= PORT_RWE;
writel(pm_val, pm_addr);
pm_val = readl(pm_addr);
pm_val |= PORT_HLE;
--
2.1.4