From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thierry Reding Subject: Re: [PATCH V7 11/12] Documentation: bridge: Add documentation for ps8622 DT properties Date: Tue, 23 Sep 2014 16:38:55 +0200 Message-ID: <20140923143854.GD5982@ulmo> References: <5419B52D.4060107@ti.com> <20140922080629.GC1470@ulmo> <542030DD.3060906@ti.com> <20140923060452.GD30514@ulmo> <5421201C.6000509@samsung.com> <20140923083514.GM30514@ulmo> <54214008.4040105@ti.com> <20140923100139.GT30514@ulmo> <54216308.2050500@ti.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============1998708128==" Return-path: In-Reply-To: <54216308.2050500@ti.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: Tomi Valkeinen Cc: "devicetree@vger.kernel.org" , "linux-samsung-soc@vger.kernel.org" , Sean Paul , Daniel Vetter , sunil joshi , "dri-devel@lists.freedesktop.org" , Andrzej Hajda , Laurent Pinchart , Ajay kumar , Prashanth G , Ajay Kumar List-Id: devicetree@vger.kernel.org --===============1998708128== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="n/aVsWSeQ4JHkrmm" Content-Disposition: inline --n/aVsWSeQ4JHkrmm Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Sep 23, 2014 at 03:09:44PM +0300, Tomi Valkeinen wrote: > On 23/09/14 13:01, Thierry Reding wrote: > > On Tue, Sep 23, 2014 at 12:40:24PM +0300, Tomi Valkeinen wrote: [...] > >> What exactly is a bridge and what is an encoder? Those are DRM > >> constructs, aren't they? > >=20 > > Yes. I think bridges are mostly a superset of encoders. >=20 > Superset in what way? If I have a SiI9022 RGB-to-HDMI encoder embedded > into my SoC (i.e. a DRM encoder), or I have a board with a SiI9022 > encoder on the board (i.e. a DRM bridge), what is different? Superset in what they represent from a software point of view. As in: an encoder /is a/ bridge. Though they aren't currently implemented that way. > >> As I see it, a video pipeline consist of a video source (display > >> controller usually), a chain of encoders (all of which may not be > >> strictly "encoders", they could be level shifters, muxes, ESD protecti= on > >> devices or such), and either a display device like a panel or a > >> connector to outside world. > >=20 > > Well, the panel itself is attached to a connector. The connector is > > really what userspace uses to control the output and indirectly the > > panel. >=20 > Yep. That's also something that should be fixed. A connector SW entity > is fine when connecting an external monitor, but a panel directly > connected to the SoC does not have a connector, and it's the panel that > should be controlled from the userspace. I disagree. A panel is usually also attached using some sort of connector. Maybe not an HDMI, VGA or DP connector, but still some sort of connector where often it can even be removed. Panels are theoretically hot-pluggable, too, much in the same way that monitors are. > But again, the legacy... You've got to make the abstraction somewhere, and I'm quite surprised actually how well the DRM abstractions are working out. I mean we can support anything from HDMI to DP to eDP, DSI and LVDS with just the connector abstraction and it all just works. That makes it a pretty good abstraction in my book. Thierry --n/aVsWSeQ4JHkrmm Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAEBAgAGBQJUIYX+AAoJEN0jrNd/PrOhLjkP/17XiQSB7ueK0cOH+A62xnh/ J/DSJ6UjelnZ3lvoUhViydBoSyp/duf3rAHRT0M+o9HvbW/qB+a4D6SA6sIR+4bp swuAXQBgHo0lWRyriOfY6CXq/9luhuc+Nd9sv433OwymL+SjRKndU8IMFI2eSDCN RMhapO4ZomB3/bF0P6NG+v9I31h/Zdtz3xqn1JmaIIp/5pHZ6viIbt7dDdXz+LiG JaPJuyJPwfTctkMS9TraGm+R1mHOX5fHm3sU8pp5BeRRbFB3TkUeKb7CHTsE+yUf SZgFGQuCKs+RU65HHJX5jiPpmWMPCbPWp1UVww0jwZs1bKdDrKd1sUFuENlI38zR bjJyVYe4uJb56hdD3VM0HJgWmKHTPraxu++9RwI9xBEGQ+okOdXEV6puJB8bju90 oNnxb3D7z4wkHxvJIKVOnSTfgFyltipmdcKudPf2pyefWSQbbqQA11+hHomZfd2I wZNZnwda3/agDRmPgmTf++Rn4g8tnV60gQSPwTVDc68T4+lS+ltM38C/RazL+/a/ SSrLfLxTPMS8Gp8tqH8sqPdK20kjP48hmHvFZv8pSb1DgncOMmzSMx1/A0tEadjx 8LA+A7gq/0yk5F6d8BoyGmTDXe4MAzHVwBGjv/AlQ9kbZLpDx4fWY4a/a7wJiLeD xYaJdXwqcHe4V0jV6YYb =DspQ -----END PGP SIGNATURE----- --n/aVsWSeQ4JHkrmm-- --===============1998708128== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/dri-devel --===============1998708128==--