From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rob Herring Subject: Re: [RFC 1/2] dt-bindings: mipi-dsi: Add info about peripherals with non-DSI control bus Date: Wed, 6 Dec 2017 15:39:36 -0600 Message-ID: <20171206213936.devr3d4fyhtbld4w@rob-hp-laptop> References: <20171205103356.9917-1-architt@codeaurora.org> <20171205103356.9917-2-architt@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-ot0-f193.google.com ([74.125.82.193]:34172 "EHLO mail-ot0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752217AbdLFVji (ORCPT ); Wed, 6 Dec 2017 16:39:38 -0500 Content-Disposition: inline In-Reply-To: <20171205103356.9917-2-architt@codeaurora.org> Sender: linux-arm-msm-owner@vger.kernel.org List-Id: linux-arm-msm@vger.kernel.org To: Archit Taneja Cc: tomi.valkeinen@ti.com, eric@anholt.net, philippe.cornu@st.com, laurent.pinchart@ideasonboard.com, thierry.reding@gmail.com, nickey.yang@rock-chips.com, dri-devel@lists.freedesktop.org, p.zabel@pengutronix.de, devicetree@vger.kernel.org, linux-arm-msm@vger.kernel.org, seanpaul@chromium.org, briannorris@chromium.org, maxime.ripard@free-electrons.com, boris.brezillon@free-electrons.com, a.hajda@samsung.com On Tue, Dec 05, 2017 at 04:03:55PM +0530, Archit Taneja wrote: > Add a section that describes dt-bindings for peripherals that support > MIPI DSI, but have a different bus as the primary control bus. Add an > example for such peripherals. > > Signed-off-by: Archit Taneja > --- > .../devicetree/bindings/display/mipi-dsi-bus.txt | 75 ++++++++++++++++++++-- > 1 file changed, 68 insertions(+), 7 deletions(-) > > diff --git a/Documentation/devicetree/bindings/display/mipi-dsi-bus.txt b/Documentation/devicetree/bindings/display/mipi-dsi-bus.txt > index 973c27273772..77a7cec15f5b 100644 > --- a/Documentation/devicetree/bindings/display/mipi-dsi-bus.txt > +++ b/Documentation/devicetree/bindings/display/mipi-dsi-bus.txt > @@ -16,7 +16,7 @@ The following assumes that only a single peripheral is connected to a DSI > host. Experience shows that this is true for the large majority of setups. > > DSI host > --------- > +======== > > In addition to the standard properties and those defined by the parent bus of > a DSI host, the following properties apply to a node representing a DSI host. > @@ -30,11 +30,15 @@ Required properties: > different value here. See below. > > DSI peripheral > --------------- > +============== > > -Peripherals are represented as child nodes of the DSI host's node. Properties > -described here apply to all DSI peripherals, but individual bindings may want > -to define additional, device-specific properties. > +Peripherals with DSI as control bus > +------------------------------------ > + > +Peripherals with the DSI bus as the primary control path are represented as > +child nodes of the DSI host's node. Properties described here apply to all DSI > +peripherals, but individual bindings may want to define additional, > +device-specific properties. Are there any panels with no control bus? I've never seen one, but it should be possible if LVDS panels can power on without commands. > Required properties: > - reg: The virtual channel number of a DSI peripheral. Must be in the range > @@ -49,9 +53,25 @@ case two alternative representations can be chosen: > property is the number of the first virtual channel and the second cell is > the number of consecutive virtual channels. > > -Example > -------- > +Peripherals with a different control bus > +---------------------------------------- > + > +There are peripherals that have I2C/SPI (or some other non-DSI bus) as the > +primary control bus, but are also connected to a DSI bus (mostly for the data > +path). Connections between such peripherals and a DSI host can be represented > +using the graph bindings [1], [2]. > + > +[1] Documentation/devicetree/bindings/graph.txt > +[2] Documentation/devicetree/bindings/media/video-interfaces.txt > > +Examples > +======== > +- (1), (2) and (3) are examples of a DSI host and peripheral on the DSI bus > + with different virtual channel configurations. > +- (4) is an example of a peripheral on a I2C control bus connected with to > + a DSI host using of-graph bindings. > + > +1) > dsi-host { > ... > > @@ -67,6 +87,7 @@ Example > ... > }; > > +2) > dsi-host { > ... > > @@ -82,6 +103,7 @@ Example > ... > }; > > +3) > dsi-host { > ... > > @@ -96,3 +118,42 @@ Example > > ... > }; > + > +4) > + i2c-host { > + ... > + > + dsi-bridge@35 { > + compatible = "..."; > + reg = <0x35>; > + > + ports { > + #address-cells = <1>; > + #size-cells = <0>; > + > + ... > + > + port@0 { Drop unit-address and #*-cells. > + bridge_mipi_in: endpoint { > + remote-endpoint = <&host_mipi_out>; > + }; > + }; > + }; > + }; > + }; > + > + dsi-host { > + ... > + > + ports { > + #address-cells = <1>; > + #size-cells = <0>; > + ... > + > + port@0 { Drop unit-address and #*-cells. > + host_mipi_out: endpoint { > + remote-endpoint = <&bridge_mipi_in>; > + }; > + }; > + }; > + }; > -- > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, > hosted by The Linux Foundation >