From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thierry Reding Subject: Re: [RFC 2/3] drm/panel: Add simple panel support Date: Wed, 4 Sep 2013 16:38:30 +0200 Message-ID: <20130904143829.GA11833@ulmo> References: <1377876321-26835-1-git-send-email-treding@nvidia.com> <1377876321-26835-3-git-send-email-treding@nvidia.com> <52262FF4.6050605@wwwdotorg.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="/04w6evG8XlLl3ft" Return-path: Content-Disposition: inline In-Reply-To: <52262FF4.6050605-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Stephen Warren Cc: dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-tegra@vger.kernel.org --/04w6evG8XlLl3ft Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Sep 03, 2013 at 12:52:36PM -0600, Stephen Warren wrote: > On 08/30/2013 09:25 AM, Thierry Reding wrote: > > Add a driver for simple panels. Such panels can have a regulator that > > provides the supply voltage and a separate GPIO to enable the panel. > > Optionally the panels can have a backlight associated with them so it > > can be enabled or disabled according to the panel's power management > > mode. >=20 > > diff --git a/Documentation/devicetree/bindings/panel/panel-simple.txt b= /Documentation/devicetree/bindings/panel/panel-simple.txt >=20 > > +Simple display panel > > + > > +Required properties: > > +- compatible: should be one of: > > + - "auo,b101aw03": AU Optronics Corporation 10.1" WSVGA TFT LCD panel > > + - "cptt,claa101wb03": Chunghwa Picture Tubes Ltd. 10.1" WXGA TFT LCD= panel > > + - "pc,vvx10f004b00": Panasonic Corporation 10.1" WUXGA TFT LCD panel > > + > > +Optional properties: > > +- ddc-i2c-bus: phandle of an I2C controller used for DDC EDID probing > > +- power-supply: regulator to provide the supply voltage > > +- enable-gpios: GPIO pin to enable or disable the panel > > +- backlight: phandle of the backlight device attached to the panel >=20 > Do we need to represent the timing requirements e.g. between panel > enable and backlight enable, or do you expect the driver to hard-code > this based on the compatible value? Yes, I'd expect the driver to hard-code that, similar to how the video mode is hardcoded. ddc-i2c-bus support hasn't even been implemented yet. I was planning to do that because one of the panels (the Chunghwa I think) actually is connected via DDC. What I was going to do was prefer a hardcoded mode over EDID to allow a driver to override a faulty EDID. > Looking at the driver code, it seems that it has direct knowledge of the > video mode that each panel supports, so DDC is actually optional unlike > what I asserted/assumed in my previous response. As such, I guess we > should have a separate DT binding document for each of the three panels > (compatible values) listed above that pretty much just says "go look at > simple-panel.txt". Okay, I suppose that makes sense. Thierry --/04w6evG8XlLl3ft Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.21 (GNU/Linux) iQIcBAEBAgAGBQJSJ0XlAAoJEN0jrNd/PrOh7iMP/AxEnK6mo55lUYijqFYMyiau frO1LmkHTqmEC11dECmjVWto8D0BPnHr0yZ+Cy8bygDpE06aqforAm2GXDW2o6bb /YbC5FTDf/SvwEZT7oGwI2H5NlR1BKscTTJM4t0uCgvjdNHOnHuhRdN873fwJkAU Y0yjJVrD+qpFP+cCUm/ZRv/0EO5SLxQJPLEJnFBcHzOnYF8pFcApc5RO8FNB2Fto a3UEyUJ7HP81JAAfcMVsWA8OcCQ/DpKbCwXjWu12wMvWRClBjTOwVG+Llx/lL+4F qn1uO5ADlJ/3WQSAv2Sz5fEgz6R6+9coKnI+innUDoP8yO16VQLvZMVOnIH3cpYN M3dpav4jNvLjEqUB5pPaSdHTJ95yp9TGr0ncPdpUbNaLbOLhLcDvJyqX6Exy2D7g lQ4/YPPqcJy5yk4TZgXOiDUAGrmcKlitCa3SPzNvslwVsOiLrrCBTb61wF16uJw7 Pk+2pWRljPN8COCyOQ//kwUI7tIEcUEIMk1ocWfiNHAAh7cyJ7ItWnuZKO3+SJ+S QdKokTfuXafhKqkjc22rQ3JAb/vHrXHc7k5nQ2lr9ZXrxjSgnjG8rsJuf4gedK3B IRqakWF4BiXTx/RuWHRdh2koIlrU7Hb11y9460w9/YXRVtkdI1akpxSy37iG1Ksd rJ52tTWH2Y1g0lkFEVKJ =nC/j -----END PGP SIGNATURE----- --/04w6evG8XlLl3ft--