Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752666AbaKQOZh (ORCPT ); Mon, 17 Nov 2014 09:25:37 -0500 Received: from regular1.263xmail.com ([211.150.99.130]:43338 "EHLO regular1.263xmail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752455AbaKQOZg (ORCPT ); Mon, 17 Nov 2014 09:25:36 -0500 X-263anti-spam: KSV:0; X-MAIL-GRAY: 0 X-MAIL-DELIVERY: 1 X-KSVirus-check: 0 X-ABS-CHECKED: 4 X-RL-SENDER: kever.yang@rock-chips.com X-FST-TO: linux-kernel@vger.kernel.org X-SENDER-IP: 127.0.0.1 X-LOGIN-NAME: kever.yang@rock-chips.com X-UNIQUE-TAG: X-ATTACHMENT-NUM: 0 X-DNS-TYPE: 0 Message-ID: <546A0554.1080809@rock-chips.com> Date: Mon, 17 Nov 2014 22:25:24 +0800 From: Kever Yang User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.0 MIME-Version: 1.0 To: Alan Stern , Julius Werner CC: Doug Anderson , Paul Zimmerman , Felipe Balbi , Dinh Nguyen , Romain Perier , Heiko Stuebner , Sonny Rao , Addy Ke , Eddie Cai , lyz , wulf , Tao Huang , "open list:ARM/Rockchip SoC..." , Greg Kroah-Hartman , "linux-usb@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v3] usb: dwc2: add bus suspend/resume for dwc2 References: In-Reply-To: Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/14/2014 11:55 PM, Alan Stern wrote: > On Thu, 13 Nov 2014, Julius Werner wrote: > >> Another thing might be that the port connect interrupt does not >> correctly resume the root hub. I don't really know many details about >> how that works, and it seems pretty complicated. But I can see that >> all other HCDs seem to call usb_hcd_resume_root_hub() from their >> interrupt handlers, which we don't. There's also a > That's how a root hub sends a wakeup request to the kernel. The > controller issues an interrupt, and when the HCD's interrupt handler > sees that the root hub is suspended, it calls usb_hcd_resume_root_hub() > instead of trying to query the hardware (because in general you _can't_ > query the hardware while it's in a low-power state). Thanks Alan and Julius, just like what you have mentioned, the dwc2 miss the usb_hcd_resume_root_hub() when root hub is suspended and device connect detected. I have send another patch for that, hope it did the right thing. - Kever -- 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/