From mboxrd@z Thu Jan 1 00:00:00 1970 From: Maxime Ripard Subject: Re: [PATCH v2 4/7] drm/bridge: Add RGB to VGA bridge support Date: Mon, 22 Aug 2016 15:37:07 +0200 Message-ID: <20160822133707.GO7104@lukather> References: <20160720095857.12297-1-maxime.ripard@free-electrons.com> <20160720095857.12297-5-maxime.ripard@free-electrons.com> <57909B8E.7030105@codeaurora.org> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============1841810655==" Return-path: In-Reply-To: <57909B8E.7030105@codeaurora.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: Archit Taneja Cc: devicetree@vger.kernel.org, dri-devel@lists.freedesktop.org, Chen-Yu Tsai , Rob Herring , Laurent Pinchart , Daniel Vetter , linux-arm-kernel@lists.infradead.org List-Id: devicetree@vger.kernel.org --===============1841810655== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="sGwo475CiIwWEjLI" Content-Disposition: inline --sGwo475CiIwWEjLI Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi Archit, On Thu, Jul 21, 2016 at 03:23:18PM +0530, Archit Taneja wrote: > Hi, >=20 > On 07/20/2016 03:28 PM, Maxime Ripard wrote: > >Some boards have an entirely passive RGB to VGA bridge, based on either > >DACs or resistor ladders. > > > >Those might or might not have an i2c bus routed to the VGA connector in > >order to access the screen EDIDs. > > > >Add a bridge that doesn't do anything but expose the modes available on = the > >screen, either based on the EDIDs if available, or based on the XGA > >standards. >=20 > Our eventual aim is to separate out the connectors from the bridge > drivers wherever possible. In the future, a KMS driver using the > bridge would be responsible for establishing the links between > the bridge and encoder, and the encoder and connector. >=20 > If in the future we remove the connector pieces from this driver > to create a separate generic VGA connector driver, we'll end up > with a bridge driver whose main functionality is to convert RGB > signals to VGA. The EDID parts would move to the VGA connector > driver. In your platform's case, there is no software needed > to translate RGB to VGA, but maybe in the future, we might need > to add an optional regulator in the driver to support another > platform. Therefore, the bridge driver would still be handy to > have. >=20 > Keeping this in consideration, I think this driver (and the DT > binding) should be called "dumb-rgb-to-vga-bridge", or > "rgb-to-vga-bridge" since that's what the bridge HW primarily > does. That works for me. I'll change it and repost. Thanks! Maxime --=20 Maxime Ripard, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com --sGwo475CiIwWEjLI Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJXuwADAAoJEBx+YmzsjxAgg90QALbltVoZD52qiGBK1rfeydrC oxaF2SpGcqaoHxBCTcUtcnt6wH6aqwKuE7cSOdaJgGj1+bvCjmy4DiQhH4z5PM8h TpVyfOX6QGtUq4xUnG4rP56y/12FYwQBQS+RjeIRpEV6qf0LbELniQ2E+0UNPdCQ aZNGlAvWjdqubGYnqVGn2fCNWSXZSWb6IC0XAvOOwhp/g99bvWgNmqa3H0vuc4Rz YKe0TBXxoVXkcLXblb6TsdCIANmrWrnBcf8tbhC+6mksa1wbrROwJ0WdkkIGQuDM 4OI57WUs7zbrLx1inwAA4pKHZoKbvViMIiW27lrTuG+R72Rs/YGPmnrWJjywTsal aVutFfxi6/X2WR37e5koROZKeNHFw4uDzieX1RYt08hD4rLQEbq23m+okKP3BSSH 4OEMHH1lrUUJSUt/tu7DnKCPaRcugIL8seQnRonn4LYuVm8dl9oM7W+k/DFnEncl j2lETkcfjcydqkvzgCUHKebfeRk/+SnK37iThWLa75IYPd9yZlISqn9txCcjX5/y fv/vRKffc0gm6u+m5NfLJEp+H+xGDDhpFdyyhQUkMEzNgLdy/HvlpdFWxFEJjNzk b/QB2iAlTKhBXIm2swstK/axFbK5r8MEu5+l9Z9jk/4CZ9dnCHzlpOdjPqQHj9vs f5Tp5MCz+OAvuyFNyed8 =K9kc -----END PGP SIGNATURE----- --sGwo475CiIwWEjLI-- --===============1841810655== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Content-Disposition: inline X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KZHJpLWRldmVs IG1haWxpbmcgbGlzdApkcmktZGV2ZWxAbGlzdHMuZnJlZWRlc2t0b3Aub3JnCmh0dHBzOi8vbGlz dHMuZnJlZWRlc2t0b3Aub3JnL21haWxtYW4vbGlzdGluZm8vZHJpLWRldmVsCg== --===============1841810655==--