From mboxrd@z Thu Jan 1 00:00:00 1970 From: Maxime Ripard Subject: Re: [PATCH v5 2/5] drm/bridge: Add RGB to VGA bridge support Date: Thu, 6 Oct 2016 09:21:06 +0200 Message-ID: <20161006072106.GA4684@lukather> References: <20160930143709.1388-1-maxime.ripard@free-electrons.com> <20160930143709.1388-3-maxime.ripard@free-electrons.com> <8795dc49-26f9-0505-f442-2ca74b51872f@codeaurora.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="OgqxwSJOaUobr8KG" Return-path: Content-Disposition: inline In-Reply-To: <8795dc49-26f9-0505-f442-2ca74b51872f-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Archit Taneja Cc: Rob Herring , Daniel Vetter , David Airlie , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Boris Brezillon , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, Chen-Yu Tsai , dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org List-Id: dri-devel@lists.freedesktop.org --OgqxwSJOaUobr8KG Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi Archit, On Mon, Oct 03, 2016 at 04:40:57PM +0530, Archit Taneja wrote: > Hi Maxime, >=20 > On 09/30/2016 08:07 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. > > > >Acked-by: Rob Herring > >Signed-off-by: Maxime Ripard > >--- > > .../bindings/display/bridge/rgb-to-vga-bridge.txt | 48 +++++ > > drivers/gpu/drm/bridge/Kconfig | 7 + > > drivers/gpu/drm/bridge/Makefile | 1 + > > drivers/gpu/drm/bridge/rgb-to-vga.c | 229 ++++++++++++++= +++++++ > > 4 files changed, 285 insertions(+) > > create mode 100644 Documentation/devicetree/bindings/display/bridge/rgb= -to-vga-bridge.txt > > create mode 100644 drivers/gpu/drm/bridge/rgb-to-vga.c > > > >diff --git a/Documentation/devicetree/bindings/display/bridge/rgb-to-vga= -bridge.txt b/Documentation/devicetree/bindings/display/bridge/rgb-to-vga-b= ridge.txt > >new file mode 100644 > >index 000000000000..a8375bc1f9cb > >--- /dev/null > >+++ b/Documentation/devicetree/bindings/display/bridge/rgb-to-vga-bridge= =2Etxt > >@@ -0,0 +1,48 @@ > >+Dumb RGB to VGA bridge > >+---------------------- > >+ > >+This binding is aimed for dumb RGB to VGA bridges that do not require > >+any configuration. > >+ > >+Required properties: > >+ > >+- compatible: Must be "rgb-to-vga-bridge" >=20 > I'd talked to Laurent on IRC if he's okay with this. And I guess you to > had discussed it during XDC too. He's suggested that it'd be better to > have the compatible string as "simple-vga-dac". I just wished this bikeshedding had taken place publicly and be actually part of that discussion, but yeah, ok. > Some of the reasons behind having this: >=20 > - We don't need to specify "rgb" in the compatible string since most > simple VGA DACs can only work with an RGB input. Ok. > - Also, with "dac" specified in the string, we don't need to > specifically mention "bridge" in the string. Also, bridge is a drm > specific term. > > - "simple" is considered because it's an unconfigurable bridge, and it > might be misleading for other VGA DACs to not use "vga-dac". All those "simple" bindings are just the biggest lie we ever told. It's simple when you introduce it, and then grows into something much more complicated than a non-simple implementation. > What do you think about this? If you think it's good, would it be > possible for you to change this? I guess it's okay for the rest of > the patch to stay the same. I'll update and respin the serie. Thanks, Maxime --=20 Maxime Ripard, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com --OgqxwSJOaUobr8KG Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJX9ftiAAoJEBx+YmzsjxAgsccP/j5G4H47nkizg7HQvLGyKD4j nWbQtZCasiRgeNbJj03zPhrPcE+cyuu+11vaG+ILr2ldDqF0dxQAOEtF5sdzAqpy lDLJUF50nAT7doM9SDj7UExUjCU1fMWwbrdpeEx81yOsFDBRJzYkvnojw42+DYCP pjQHM9lNa+2RL11Cpjfj60CLmT/BWNGHP29LRMFsG8nrIKGOpUg2GbEBrwBP0Qus JZsJWtSJqF55AmshSw6yvsp4oJYDo52HFWls/rmu8TTw2BThdnbXBne2CZG0lBwf LX4l7JEYFF+HtSIYTHnO6pozdy9972LxC2if1M14YD3jot6Mn3n9z4TLaiBQG3LW qc71NkPHFQoTbHHD09kRYu59M38jSphq3YwG3tsywpGIA2XQsIJ56SEClUmEP7d8 Oc9IO+lVrvoQY2bJCXtLtROIzf5YhumXF9tTfkq4NbPzo2hQscVHmO4oJCWC/N5U PjRTN7VnWsVF4wmxMwpzcr3tQlPwPZOondgYft6jWLR7UN7LgS2lCJDoscE7QcC7 uHV0WZlWuTiW33nufO4M7m5V9gc+bLyPCfqoyF7suGRwd8pyS75Ga2fJPmR0JSrb LH1Y8GP9TGXhDpa1USYbmyFJ0ppeDRFaHpLy1AF+IzxeoAvziDaM+Gzwhe9YQfLD uTxS0CQ++BxA96S7+L+D =HSc7 -----END PGP SIGNATURE----- --OgqxwSJOaUobr8KG-- -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html