Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755308Ab2E1DqI (ORCPT ); Sun, 27 May 2012 23:46:08 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:52048 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753865Ab2E1D32 (ORCPT ); Sun, 27 May 2012 23:29:28 -0400 Message-Id: <20120528031211.291417478@decadent.org.uk> User-Agent: quilt/0.60-1 Date: Mon, 28 May 2012 04:13:03 +0100 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Andiry Xu , Sarah Sharp Subject: [ 061/117] usbcore: enable USB2 LPM if port suspend fails In-Reply-To: <20120528031202.829379252@decadent.org.uk> X-SA-Exim-Connect-IP: 192.168.4.185 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1652 Lines: 48 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Andiry Xu commit c3e751e4f4754793bb52bd5ae30e9cc027edbb12 upstream. USB2 LPM is disabled when device begin to suspend and enabled after device is resumed. That's because USB spec does not define the transition from U1/U2 state to U3 state. If usb_port_suspend() fails, usb_port_resume() is never called, and USB2 LPM is disabled in this situation. Enable USB2 LPM if port suspend fails. This patch should be backported to kernels as old as 3.2, that contain the commit 65580b4321eb36f16ae8b5987bfa1bb948fc5112 "xHCI: set USB2 hardware LPM". Signed-off-by: Andiry Xu Signed-off-by: Sarah Sharp Signed-off-by: Ben Hutchings --- drivers/usb/core/hub.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index ec6c97d..c8e0704 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -2499,6 +2499,10 @@ int usb_port_suspend(struct usb_device *udev, pm_message_t msg) NULL, 0, USB_CTRL_SET_TIMEOUT); + /* Try to enable USB2 hardware LPM again */ + if (udev->usb2_hw_lpm_capable == 1) + usb_set_usb2_hardware_lpm(udev, 1); + /* System sleep transitions should never fail */ if (!PMSG_IS_AUTO(msg)) status = 0; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/