From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vikas Sajjan Subject: Re: [PATCH 3/3] ARM: dts: Add display timing node to exynos5250-arndale.dts Date: Fri, 10 May 2013 11:57:34 +0530 Message-ID: References: <1367992894-20198-1-git-send-email-vikas.sajjan@linaro.org> <1367992894-20198-4-git-send-email-vikas.sajjan@linaro.org> <4212940.hYf2k9NPUY@flatron> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============0293832027757489628==" Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org Sender: "devicetree-discuss" To: Olof Johansson Cc: "linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org" , Tomasz Figa , InKi Dae , "kgene.kim" , Sylwester Nawrocki List-Id: devicetree@vger.kernel.org --===============0293832027757489628== Content-Type: multipart/alternative; boundary=001a11c34a3a697dc404dc574420 --001a11c34a3a697dc404dc574420 Content-Type: text/plain; charset=ISO-8859-1 Hi Olof, On 10 May 2013 11:51, Vikas Sajjan wrote: > Hi Olof, > > > On 10 May 2013 11:08, Olof Johansson wrote: > >> On Thu, May 9, 2013 at 7:55 PM, Vikas Sajjan >> wrote: >> > Hi Tomasz, >> > >> > >> > On 10 May 2013 05:35, Tomasz Figa wrote: >> >> >> >> Hi Vikas, >> >> >> >> On Wednesday 08 of May 2013 11:31:34 Vikas Sajjan wrote: >> >> > Adds display timing node for a DP panel to Arndale Board DTS file >> >> > >> >> > Signed-off-by: Vikas Sajjan >> >> > --- >> >> > arch/arm/boot/dts/exynos5250-arndale.dts | 16 ++++++++++++++++ >> >> > 1 file changed, 16 insertions(+) >> >> > >> >> > diff --git a/arch/arm/boot/dts/exynos5250-arndale.dts >> >> > b/arch/arm/boot/dts/exynos5250-arndale.dts index f68b820..c831a5c >> >> > 100644 >> >> > --- a/arch/arm/boot/dts/exynos5250-arndale.dts >> >> > +++ b/arch/arm/boot/dts/exynos5250-arndale.dts >> >> > @@ -459,4 +459,20 @@ >> >> > samsung,lane-count = <4>; >> >> > }; >> >> > >> >> > + display-timings { >> >> > + native-mode = <&timing0>; >> >> > + timing0: timing@0 { >> >> > + /* 2560x1600 DP panel */ >> >> > + clock-frequency = <50000>; >> >> > + hactive = <2560>; >> >> > + vactive = <1600>; >> >> > + hfront-porch = <48>; >> >> > + hback-porch = <80>; >> >> > + hsync-len = <32>; >> >> > + vback-porch = <16>; >> >> > + vfront-porch = <8>; >> >> > + vsync-len = <6>; >> >> > + }; >> >> > + }; >> >> >> >> What display are those timings used for? Shouldn't they be placed >> inside >> >> node of that display? >> >> >> > >> > This timing information will be used parsed by the FIMD probe with the >> help >> > of "Video Helper function" as done in this link >> > >> > >> https://git.kernel.org/cgit/linux/kernel/git/daeinki/drm-exynos.git/commit/?h=exynos-drm-next&id=7f4596f4aebcc9fcf2d50d3fe398508d710c4dd0 >> >> That function passes in a device node pointer to the FIMD device node, >> and only looks for a display-timings node under there. Tomasz is >> right, as far as I can tell. >> >> Placing display timings at the root of the device tree seems completely >> wrong. >> >> I referred this " Documentation/devicetree/bindings/video/display-timing.txt" for example here it dosen't mention about whether display timings node can be placed at the root of the device tree or NOT. Not sure how we should be placing the node then. > > >> > Please refer to this patch which is used for exynos4412-origen and >> > exynos5250-smdk5250 respectively in similar way >> > >> > >> https://git.kernel.org/cgit/linux/kernel/git/kgene/linux-samsung.git/commit/?h=for-next&id=0207775d6ff7e6a6eddb9931f9328f0f0173a338 >> > >> > >> https://git.kernel.org/cgit/linux/kernel/git/kgene/linux-samsung.git/commit/?h=for-next&id=06c460b73f75894cabfb1f5277f27cddbc92745c >> >> That needs to be fixed up as well, thanks for pointing it out. >> >> >> -Olof >> > > > > -- > Thanks and Regards > Vikas Sajjan > -- Thanks and Regards Vikas Sajjan --001a11c34a3a697dc404dc574420 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
Hi Olof,


On 10 May 2013 11:51, Vikas Sajjan <<= a href=3D"mailto:vikas.sajjan-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org" target=3D"_blank">vikas.sajjan@li= naro.org> wrote:
Hi Olof,=


On 10 May 2013 11:08, Olof Johansson <olof-nZhT3qVonbNeoWH0uzbU5w@public.gmane.org> wrote:
On Thu, May 9, = 2013 at 7:55 PM, Vikas Sajjan <vikas.sajjan-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> wrote:
> Hi Tomasz,
>
>
> On 10 May 2013 05:35, Tomasz Figa <tomasz.figa-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>>
>> Hi Vikas,
>>
>> On Wednesday 08 of May 2013 11:31:34 Vikas Sajjan wrote:
>> > Adds display timing node for a DP panel to Arndale Board DTS = file
>> >
>> > Signed-off-by: Vikas Sajjan <vikas.sajjan-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
>> > ---
>> > =A0arch/arm/boot/dts/exynos5250-arndale.dts | =A0 16 ++++++++= ++++++++
>> > =A01 file changed, 16 insertions(+)
>> >
>> > diff --git a/arch/arm/boot/dts/exynos5250-arndale.dts
>> > b/arch/arm/boot/dts/exynos5250-arndale.dts index f68b820..c83= 1a5c
>> > 100644
>> > --- a/arch/arm/boot/dts/exynos5250-arndale.dts
>> > +++ b/arch/arm/boot/dts/exynos5250-arndale.dts
>> > @@ -459,4 +459,20 @@
>> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 samsung,lane-count =3D <4>;=
>> > =A0 =A0 =A0 };
>> >
>> > + =A0 =A0 display-timings {
>> > + =A0 =A0 =A0 =A0 =A0 =A0 native-mode =3D <&timing0>= ;;
>> > + =A0 =A0 =A0 =A0 =A0 =A0 timing0: timing@0 {
>> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 /* 2560x1600 DP pan= el */
>> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 clock-frequency =3D= <50000>;
>> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 hactive =3D <256= 0>;
>> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 vactive =3D <160= 0>;
>> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 hfront-porch =3D &l= t;48>;
>> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 hback-porch =3D <= ;80>;
>> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 hsync-len =3D <3= 2>;
>> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 vback-porch =3D <= ;16>;
>> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 vfront-porch =3D &l= t;8>;
>> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 vsync-len =3D <6= >;
>> > + =A0 =A0 =A0 =A0 =A0 =A0 };
>> > + =A0 =A0 };
>>
>> What display are those timings used for? Shouldn't they be pla= ced inside
>> node of that display?
>>
>
> This timing information will be used parsed by the FIMD probe with the= help
> of "Video Helper function" =A0as done in this link
>
> https://git.kernel.org/cgit/linux/kernel/git= /daeinki/drm-exynos.git/commit/?h=3Dexynos-drm-next&id=3D7f4596f4aebcc9= fcf2d50d3fe398508d710c4dd0

That function passes in a device node pointer to the FIMD devic= e node,
and only looks for a display-timings node under there. Tomasz is
right, as far as I can tell.

Placing display timings at the root of the device tree seems completely wro= ng.

=A0 =A0 =A0 =A0 I referred this " Documentation/devicetree/bindings/v= ideo/display-timing.txt" for example

=A0=A0=A0=A0=A0= =A0=A0=A0=A0=A0=A0 here it dosen't mention about whether display timing= s node can be placed at the root of the device tree or NOT.
=A0Not sure how we should be placing the node then.
=A0
=A0
That needs to be fixed up as well, thanks for pointing it out.


-Olof



--
Thanks and Regards
=A0Vikas Sajjan



--
Thanks and Regards
= =A0Vikas Sajjan
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