From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mx1.redhat.com ([209.132.183.28]:49887 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756833Ab3BKOwN (ORCPT ); Mon, 11 Feb 2013 09:52:13 -0500 Message-ID: <5119064C.8040807@redhat.com> Date: Mon, 11 Feb 2013 15:55:08 +0100 From: Hans de Goede MIME-Version: 1.0 To: Hans Verkuil CC: Arvydas Sidorenko , linux-media@vger.kernel.org Subject: Re: [RFCv2 PATCH 01/12] stk-webcam: the initial hflip and vflip setup was the wrong way around References: <1360518773-1065-1-git-send-email-hverkuil@xs4all.nl> <201302111421.17226.hverkuil@xs4all.nl> <5118F4F4.1070602@redhat.com> <201302111451.31133.hverkuil@xs4all.nl> In-Reply-To: <201302111451.31133.hverkuil@xs4all.nl> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: Hi, On 02/11/2013 02:51 PM, Hans Verkuil wrote: > On Mon February 11 2013 14:41:08 Hans de Goede wrote: >> Hi, >> >> On 02/11/2013 02:21 PM, Hans Verkuil wrote: >>> On Mon February 11 2013 14:08:44 Hans de Goede wrote: >>>> Hi, >>>> >>>> Subject: stk-webcam: the initial hflip and vflip setup was the wrong way around >>>> >>>> No it is not. >>> >>> You are right, that patch makes no sense. It was a long day :-) >>> >>>> On 02/10/2013 06:52 PM, Hans Verkuil wrote: >>>>> From: Hans Verkuil >>>>> >>>>> This resulted in an upside-down picture. >>>> >>>> No it does not, the laptop having an upside down mounted camera and not being >>>> in the dmi-table is what causes an upside down picture. For a non upside >>>> down camera (so no dmi-match) hflip and vflip should be 0. >>>> >>>> The fix for the upside-down-ness Arvydas Sidorenko reported would be to >>>> add his laptop to the upside down table. >>> >>> That doesn't make sense either. Arvydas, it worked fine for you before, right? >> >> Yes, it probably worked before, but not with... >> >>> That is, if you use e.g. v3.8-rc7 then your picture is the right side up. >> >> 3.8 will show it upside down for Arvydas >> >> The story goes likes this: >> >> 1) Once upon a time the stkwebcam driver was written >> 2) The webcam in question was used mostly in Asus laptop models, including >> the laptop of the original author of the driver, and in these models, in >> typical Asus fashion (see the long long list for uvc cams inside v4l-utils), >> they mounted the webcam-module the wrong way up. So the hflip and vflip >> module options were given a default value of 1 (the correct value for >> upside down mounted models) >> >> 3) Years later I got a bug report from a user with a laptop with stkwebcam, >> where the module was actually mounted the right way up, and thus showed upside >> down under Linux. So now I was facing the choice of 2 options: >> a) Add a not-upside-down list to stkwebcam, which overrules the default >> b) Do it like all the other drivers do, and make the default right for >> cams mounted the proper way and add an upside-down model list, with models >> where we need to flip-by-default. >> >> Despite knowing that going b) would cause a period of pain where we were >> building the table (ie what we're discussing now) I opted to go for option >> b), since a) is just too ugly, and worse different from how every other >> driver does it leading to confusion in the long run. >> >> IOW this is entirely my fault, and I take full responsibility for it. > > Ah, OK. Now it makes sense. I wasn't aware of this history and it (clearly) > confused me greatly. > > Can you perhaps provide me with a patch that adds some comments to the source > explaining this. And in particular with which kernel this change took place? Feel free to copy my 1) - 3) From above to a comment, step 3 landed in kernel 3.6 (you doing it seems better then me doing a patch conflicting with your patchset) > The next time some poor sod (e.g. me) has to work on this the comments should > explain this history. Ack. Regards, Hans