All of lore.kernel.org
 help / color / mirror / Atom feed
From: Vikas Sajjan <vikas.sajjan-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
To: Tomasz Figa <tomasz.figa-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>,
	s.trumtrar-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org,
	swarren-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org,
	Philipp Zabel <p.zabel-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
Cc: "linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org"
	<linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>,
	"devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org"
	<devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org>,
	InKi Dae <inki.dae-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>,
	"kgene.kim" <kgene.kim-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>,
	Sylwester Nawrocki
	<s.nawrocki-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
Subject: Re: [PATCH 3/3] ARM: dts: Add display timing node to exynos5250-arndale.dts
Date: Fri, 10 May 2013 13:45:27 +0530	[thread overview]
Message-ID: <CAD025ySqUpGRpx0J61gsjKE_JPa+Mu444ETpd2USyikrNWj71w@mail.gmail.com> (raw)
In-Reply-To: <1853757.ubr759t9No@flatron>


[-- Attachment #1.1: Type: text/plain, Size: 3923 bytes --]

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 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>
> > >> >> > ---
> > >> >> >
> > >> >> >  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.

Best regards,
> Tomasz
>
>


-- 
Thanks and Regards
 Vikas Sajjan

[-- Attachment #1.2: Type: text/html, Size: 6391 bytes --]

[-- Attachment #2: Type: text/plain, Size: 192 bytes --]

_______________________________________________
devicetree-discuss mailing list
devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org
https://lists.ozlabs.org/listinfo/devicetree-discuss

  reply	other threads:[~2013-05-10  8:15 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-05-08  6:01 [PATCH 0/3] Add DP related DT and Display-timing Node to exynos5250 based Arndale Board Vikas Sajjan
2013-05-08  6:01 ` [PATCH 1/3] ARM: dts: Add DT node for DP controller for " Vikas Sajjan
2013-05-13  1:20   ` Jingoo Han
2013-06-05 11:26     ` Kukjin Kim
2013-06-05 11:43     ` Kukjin Kim
2013-05-08  6:01 ` [PATCH 2/3] ARM: dts: Add clock provider information for DP controller in Exynos5250 SoC Vikas Sajjan
2013-05-13  1:21   ` Jingoo Han
2013-06-05 11:25     ` Kukjin Kim
2013-05-08  6:01 ` [PATCH 3/3] ARM: dts: Add display timing node to exynos5250-arndale.dts Vikas Sajjan
2013-05-10  0:05   ` Tomasz Figa
2013-05-10  2:55     ` Vikas Sajjan
     [not found]       ` <CAD025yRnuk2oK1B40p5XTQ7n+aX+ta2PTdEuceCbvRUEvRgzSg-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-05-10  3:58         ` Vikas Sajjan
2013-05-10  5:38       ` Olof Johansson
     [not found]         ` <CAOesGMg0LLhC7=EYtWxaDL5x=v=ZA6ov5K_j-nxhzev4L-w-Rg-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-05-10  6:21           ` Vikas Sajjan
     [not found]             ` <CAD025yQ+vnNc1RqoqoBw9JqYUp6aAY2wTowhVyV+zoDZq9sJ6g-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-05-10  6:27               ` Vikas Sajjan
2013-05-10  7:33                 ` Tomasz Figa
2013-05-10  8:15                   ` Vikas Sajjan [this message]
     [not found]                     ` <CAD025ySqUpGRpx0J61gsjKE_JPa+Mu444ETpd2USyikrNWj71w-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-05-14 13:10                       ` Vikas Sajjan
2013-05-14 13:25                         ` Steffen Trumtrar
     [not found]                           ` <20130514132523.GA10292-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
2013-05-14 13:39                             ` Vikas Sajjan

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=CAD025ySqUpGRpx0J61gsjKE_JPa+Mu444ETpd2USyikrNWj71w@mail.gmail.com \
    --to=vikas.sajjan-qsej5fyqhm4dnm+yrofe0a@public.gmane.org \
    --cc=devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org \
    --cc=inki.dae-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org \
    --cc=kgene.kim-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org \
    --cc=linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
    --cc=p.zabel-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org \
    --cc=s.nawrocki-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org \
    --cc=s.trumtrar-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org \
    --cc=swarren-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org \
    --cc=tomasz.figa-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.