Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757990Ab3DXJR4 (ORCPT ); Wed, 24 Apr 2013 05:17:56 -0400 Received: from perceval.ideasonboard.com ([95.142.166.194]:42216 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751917Ab3DXJRy (ORCPT ); Wed, 24 Apr 2013 05:17:54 -0400 From: Laurent Pinchart To: adam.lee@canonical.com Cc: linux-kernel@vger.kernel.org, Matthew Garrett , Mauro Carvalho Chehab , "open list:USB VIDEO CLASS" Subject: Re: [PATCH] Revert "V4L/DVB: uvc: Enable USB autosuspend by default on uvcvideo" Date: Wed, 24 Apr 2013 11:17:52 +0200 Message-ID: <6159110.qEtHHiJYtm@avalon> User-Agent: KMail/4.10.2 (Linux/3.7.10-gentoo; KDE/4.10.2; x86_64; ; ) In-Reply-To: <1366790239-838-1-git-send-email-adam.lee@canonical.com> References: <1366790239-838-1-git-send-email-adam.lee@canonical.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2015 Lines: 58 Hi Adam, Thanks for the patch. On Wednesday 24 April 2013 15:57:19 adam.lee@canonical.com wrote: > From: Adam Lee > > This reverts commit 3dae8b41dc5651f8eb22cf310e8b116480ba25b7. > > 1, I do have a Chicony webcam, implements autosuspend in a broken way, > make `poweroff` performs rebooting when its autosuspend enabled. > > 2, There are other webcams which don't support autosuspend too, like > https://patchwork.kernel.org/patch/2356141/ > > 3, kernel removed USB_QUIRK_NO_AUTOSUSPEND in > a691efa9888e71232dfb4088fb8a8304ffc7b0f9, because autosuspend is > disabled by default. > > So, we need to disable autosuspend in uvcvideo, maintaining a quirk list > only for uvcvideo is not a good idea. > > Signed-off-by: Adam Lee I've received very few bug reports about broken auto-suspend support in UVC devices. Most of them could be solved by setting the RESET_RESUME quirk in USB core, only the Creative Live! Cam Optia AF required a quirk in the uvcvideo driver. I would thus rather use the available quirks (USB_QUIRK_RESET_RESUME if possible, UVC_QUIRK_DISABLE_AUTOSUSPEND otherwise) than killing power management for the vast majority of webcams that behave correctly. > --- > drivers/media/usb/uvc/uvc_driver.c | 1 - > 1 file changed, 1 deletion(-) > > diff --git a/drivers/media/usb/uvc/uvc_driver.c > b/drivers/media/usb/uvc/uvc_driver.c index 5dbefa6..8556f7c 100644 > --- a/drivers/media/usb/uvc/uvc_driver.c > +++ b/drivers/media/usb/uvc/uvc_driver.c > @@ -1914,7 +1914,6 @@ static int uvc_probe(struct usb_interface *intf, > } > > uvc_trace(UVC_TRACE_PROBE, "UVC device initialized.\n"); > - usb_enable_autosuspend(udev); > return 0; > > error: -- Regards, Laurent Pinchart -- 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/