From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrzej Hajda Subject: Re: [PATCH v3 2/2] dt-bindings: drm/bridge: Document Cadence DSI bridge bindings Date: Fri, 01 Sep 2017 09:26:11 +0200 Message-ID: <9cc75e8e-a300-1bdf-1aa4-c20b9aa77c42@samsung.com> References: <20170831155519.3704-1-boris.brezillon@free-electrons.com> <20170831155519.3704-2-boris.brezillon@free-electrons.com> <3371dbd2-9539-d746-0982-71112d5d98a0@samsung.com> <20170901090654.343c7853@bbrezillon> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: In-reply-to: <20170901090654.343c7853@bbrezillon> Content-language: en-US Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Boris Brezillon Cc: David Airlie , Daniel Vetter , dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, Archit Taneja , Mark Rutland , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Cyprian Wronka , Thomas Petazzoni , Pawel Moll , Ian Campbell , Simon Hatliff , Tomi Valkeinen , Jyri Sarha , Alan Douglas , Rob Herring , Kumar Gala , Maxime Ripard , Richard Sproul , Neil Webb List-Id: devicetree@vger.kernel.org On 01.09.2017 09:06, Boris Brezillon wrote: > Hi Andrzej, > > On Fri, 01 Sep 2017 08:28:13 +0200 > Andrzej Hajda wrote: > >> On 31.08.2017 17:55, Boris Brezillon wrote: >>> Document the bindings used for the Cadence DSI bridge. >>> >>> Signed-off-by: Boris Brezillon >>> --- >>> Changes in v3: >>> - Fix clock names in the example >>> - Document how to represent DSI devices that are controller through >>> an external bus like I2C or SPI >>> >>> Changes in v2: >>> - None >>> --- >>> .../bindings/display/bridge/cdns,dsi.txt | 109 +++++++++++++++++++++ >>> 1 file changed, 109 insertions(+) >>> create mode 100644 Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt >>> >>> diff --git a/Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt b/Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt >>> new file mode 100644 >>> index 000000000000..c70008bd8c0d >>> --- /dev/null >>> +++ b/Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt >>> @@ -0,0 +1,109 @@ >>> +Cadence DSI bridge >>> +================== >>> + >>> +The Cadence DSI bridge is a DPI to DSI bridge supporting up to 4 DSI lanes. >>> + >>> +Required properties: >>> +- compatible: should be set to "cdns,dsi-1.3.1". >>> +- reg: physical base address and length of the controller's registers. >>> +- interrupts: interrupt line connected to the DSI bridge. >>> +- clocks: DSI bridge clocks. >>> +- clock-names: must contain "pclk" and "sysclk". >>> +- phys: phandle link to the MIPI D-PHY controller. >>> +- phy-names: must contain "dphy". >>> +- #address-cells: must be set to 1. >>> +- #size-cells: must be set to 0. >>> + >>> +Required subnodes: >>> +- ports: Ports as described in Documentation/devicetree/bindings/graph.txt. >>> + 2 ports are available: >>> + * port 0: this port is only needed if some of your DSI devices are >>> + controlled through an external bus like I2C or SPI. Can have at >>> + most 4 endpoints. The endpoint number is directly encoding the >>> + DSI virtual channel used by this device. >>> + * port 1: represents the DPI input. >>> + Other ports will be added later to support the new kind of inputs. >> I think usual practice is to use lower numbers for input ports, higher >> for output ports. >> Is there a reason to do it this way? > The main reason I did that is because we only have one output port and > can have 1, 2 or 3 input ports: one is the DPI and the 2 others are > called SDI (some kind of serial input). I thought it would be better to > have all inputs using contiguous port numbers, and if we put inputs > first that means having a hole between the input and output port (port 0 > would be the DPI input and port 3 the DSI output). > > Honestly, that's just a detail, so if you prefer to have the input > ports start at 0 I'm fine with that. No serious preferences, just curiosity. In fact port numbering schema is private thing of the device node. Regards Andrzej > > Regards, > > Boris > > > > > -- 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