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: Tue, 14 May 2013 19:09:09 +0530 Message-ID: References: <1367992894-20198-1-git-send-email-vikas.sajjan@linaro.org> <1853757.ubr759t9No@flatron> <20130514132523.GA10292@pengutronix.de> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============0359250580537937664==" Return-path: In-Reply-To: <20130514132523.GA10292-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org> 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: Steffen Trumtrar Cc: "kgene.kim" , Stephen Warren , Sylwester Nawrocki , "s.hauer" , Tomasz Figa , InKi Dae , "linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Philipp Zabel , "devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org" List-Id: devicetree@vger.kernel.org --===============0359250580537937664== Content-Type: multipart/alternative; boundary=001a11c34a3a36945a04dcadc396 --001a11c34a3a36945a04dcadc396 Content-Type: text/plain; charset=ISO-8859-1 Thanks, we test and resend v2 patchset. On 14 May 2013 18:55, Steffen Trumtrar wrote: > Hi! > > On Tue, May 14, 2013 at 06:40:00PM +0530, Vikas Sajjan wrote: > > Hi Steffen Trumtrar and Sascha Hauer, > > > > Olof and Tomasz Figa have a concern in putting "display-timings" as root > > node in device tree file. > > > > > > On 10 May 2013 13:45, Vikas Sajjan wrote: > > > > > HI Tomasz, > > > > > > > > > On 10 May 2013 13:03, Tomasz Figa wrote: > > > > > >> On Friday 10 of May 2013 11:57:34 Vikas Sajjan wrote: > > >> > 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/c > > >> > >> > ommit/?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. > > >> > > >> I think this is pretty obvious. > > >> > > >> Imagine a bit more complex case: a board has two video outputs (let's > say > > >> FIMD0 and FIMD1), each connected to a completely different display. > This > > >> means that each display needs different timings. > > >> > > >> How would you know which timings to use if all of them were be placed > > >> under the root node? > > >> > > >> so what do you think, how should we modify this patch so that it > > > belongs to a specific video outputs. > > > > > > > > > > So what do you think, how should we modify this patch so that it > belongs > > to a specific video outputs. > > > Something like > > &fimd { > display-timings { > timing0: timing@0 { > /* 2560x1600 DP panel */ > clock-frequency = <50000>; > hactive = <2560>; > vactive = <1600>; > hfront-porch = <48>; > (...) > }; > }; > }; > > Would be correct, if fimd is the output on which the display is connected. > The fimd driver than has to utilize of_get_display_timings, > of_get_fb_videomode > or something like that. > > Regards, > Steffen > > -- > Pengutronix e.K. | | > Industrial Linux Solutions | http://www.pengutronix.de/ | > Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | > Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | > -- Thanks and Regards Vikas Sajjan --001a11c34a3a36945a04dcadc396 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
Thanks, we test and resend v2 patchset.


On 14 May 2013 18:55, = Steffen Trumtrar <s.trumtrar-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org> wrote:<= br>
Hi!

On Tue, May 14, 2013 at 06:40:00PM +0530, Vikas Sajjan wrote:
> Hi Steffen Trumtrar and Sascha Hauer,
>
> Olof and Tomasz Figa have a concern in putting "display-timings&q= uot; =A0as root
> node in device tree file.
>
>
> On 10 May 2013 13:45, Vikas Sajjan <vikas.sajjan-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> wrote:
>
> > HI Tomasz,
> >
> >
> > On 10 May 2013 13:03, Tomasz Figa <tomasz.figa-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> >
> >> On Friday 10 of May 2013 11:57:34 Vikas Sajjan wrote:
> >> > Hi Olof,
> >> >
> >> > On 10 May 2013 11:51, Vikas Sajjan <vikas.sajjan-QSEj5FYQhm4dnm+yROfE0A@public.gmane.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 V= ikas Sajjan wrote:
> >> > >> >> > Adds display timing node for a DP= panel to Arndale Board DTS
> >> > >> >> > file
> >> > >> >> >
> >> > >> >> > Signed-off-by: Vikas Sajjan <<= a href=3D"mailto:vikas.sajjan-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org">vikas.sajjan-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> > >> > >> >> > ---
> >> > >> >> >
> >> > >> >> > =A0arch/arm/boot/dts/exynos5250-a= rndale.dts | =A0 16
> >> > >> >> > =A0++++++++++++++++
> >> > >> >> > =A01 file changed, 16 insertions(= +)
> >> > >> >> >
> >> > >> >> > diff --git a/arch/arm/boot/dts/ex= ynos5250-arndale.dts
> >> > >> >> > b/arch/arm/boot/dts/exynos5250-ar= ndale.dts index
> >> > >> >> > f68b820..c831a5c
> >> > >> >> > 100644
> >> > >> >> > --- a/arch/arm/boot/dts/exynos525= 0-arndale.dts
> >> > >> >> > +++ b/arch/arm/boot/dts/exynos525= 0-arndale.dts
> >> > >> >> > @@ -459,4 +459,20 @@
> >> > >> >> >
> >> > >> >> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 samsu= ng,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 panel */
> >> > >> >> > + =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 <2560>;
> >> > >> >> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0= =A0 =A0 vactive =3D <1600>;
> >> > >> >> > + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0= =A0 =A0 hfront-porch =3D <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 <32>;
> >> > >> >> > + =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 <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 fo= r? Shouldn't they be placed
> >> > >>
> >> > >> inside
> >> > >>
> >> > >> >> node of that display?
> >> > >> >
> >> > >> > This timing information will be used parse= d by the FIMD probe with
> >> > >> > the
> >> > >>
> >> > >> help
> >> > >>
> >> > >> > of "Video Helper function" =A0as= done in this link
> >> > >>
> >> > >>
> >> https://git.kernel.org/cgit/linux/ke= rnel/git/daeinki/drm-exynos.git/c
> >> > >> ommit/?h=3Dexynos-drm-next&id=3D7f4596f4aeb= cc9fcf2d50d3fe398508d710c4dd0
> >> > >>
> >> > >> That function passes in a device node pointer t= o 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 devi= ce tree seems
> >> > >> completely
> >> > >> wrong.
> >> > >>
> >> > >> =A0 =A0 =A0 =A0 I referred this "
> >> >
> >> > Documentation/devicetree/bindings/video/display-timing.t= xt" for example
> >> >
> >> > =A0 =A0 =A0 =A0 =A0 =A0 here it dosen't mention abou= t whether display timings node
> >> > can be placed at the root of the device tree or NOT.
> >> > =A0Not sure how we should be placing the node then.
> >>
> >> I think this is pretty obvious.
> >>
> >> Imagine a bit more complex case: a board has two video output= s (let's say
> >> FIMD0 and FIMD1), each connected to a completely different di= splay. This
> >> means that each display needs different timings.
> >>
> >> How would you know which timings to use if all of them were b= e placed
> >> under the root node?
> >>
> >> =A0 =A0 so what do you think, how =A0should we modify this pa= tch so that it
> > belongs to a specific video outputs.
> >
> >
>
> =A0 So what do you think, how should we modify this patch so that it b= elongs
> to a specific video outputs.
>
=A0Something like

=A0 =A0 =A0 =A0 &fimd {
=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 display-timings {
=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 timing0: timing@0 {
=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 = =A0 =A0 /* 2560x1600 DP panel */
=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 clock= -frequency =3D <50000>;
=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 hactive =3D= <2560>;
=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 vactive =3D= <1600>;
=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 hfront-porc= h =3D <48>;
=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 (...)
=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 };
=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 };
=A0 =A0 =A0 =A0 };

Would be correct, if fimd is the output on which the display is connected.<= br> The fimd driver than has to utilize of_get_display_timings, of_get_fb_video= mode
or something like that.

Regards,
Steffen

--
Pengutronix e.K. =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 | =A0 = =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 |
Industrial Linux Solutions =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 | http://www.pengutronix.de/ = =A0|
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 =A0 = =A0|
Amtsgericht Hildesheim, HRA 2686 =A0 =A0 =A0 =A0 =A0 | Fax: =A0 +49-5121-20= 6917-5555 |



--
Thanks an= d Regards
=A0Vikas Sajjan
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