From mboxrd@z Thu Jan 1 00:00:00 1970 From: Xin Ji Subject: Re: [PATCH v2 1/2] dt-bindings: drm/bridge: anx7625: MIPI to DP transmitter binding Date: Mon, 14 Oct 2019 03:02:48 +0000 Message-ID: <20191014030238.GB2390@xin-VirtualBox> References: <75bb8a47d2c3c1f979c6d62158c21988b846e79b.1570760115.git.xji@analogixsemi.com> <3c6067de-9f3c-b93c-f263-fa5dd09c3270@samsung.com> <20191011125418.GE4882@pendragon.ideasonboard.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <20191011125418.GE4882@pendragon.ideasonboard.com> Content-Language: en-US Content-ID: Sender: linux-kernel-owner@vger.kernel.org Cc: "devel@driverdev.osuosl.org" , Laurent Pinchart , Dan Carpenter , Andrzej Hajda , Neil Armstrong , Jonas Karlman , Jernej Skrabec , David Airlie , Daniel Vetter , "linux-kernel@vger.kernel.org" , "dri-devel@lists.freedesktop.org" , Sheng Pan List-Id: dri-devel@lists.freedesktop.org Hi Laurent Pinchart, please check my comment below. Thanks, Xin On Fri, Oct 11, 2019 at 03:54:18PM +0300, Laurent Pinchart wrote: > Hi Andrzej, >=20 > On Fri, Oct 11, 2019 at 01:21:43PM +0200, Andrzej Hajda wrote: > > On 11.10.2019 04:21, Xin Ji wrote: > > > The ANX7625 is an ultra-low power 4K Mobile HD Transmitter designed > > > for portable device. It converts MIPI to DisplayPort 1.3 4K. > > > > > > You can add support to your board with binding. > > > > > > Example: > > > anx7625_bridge: encoder@58 { > > > compatible =3D "analogix,anx7625"; > > > reg =3D <0x58>; > > > status =3D "okay"; > > > panel-flags =3D <1>; > > > enable-gpios =3D <&pio 45 GPIO_ACTIVE_HIGH>; > > > reset-gpios =3D <&pio 73 GPIO_ACTIVE_HIGH>; > > > #address-cells =3D <1>; > > > #size-cells =3D <0>; > > > > > > port@0 { > > > reg =3D <0>; > > > anx_1_in: endpoint { > > > remote-endpoint =3D <&mipi_dsi>; > > > }; > > > }; > > > > > > port@3 { > > > reg =3D <3>; > > > anx_1_out: endpoint { > > > remote-endpoint =3D <&panel_in>; > > > }; > > > }; > > > }; > > > > > > Signed-off-by: Xin Ji > > > --- > > > .../bindings/display/bridge/anx7625.yaml | 96 ++++++++++++= ++++++++++ > > > 1 file changed, 96 insertions(+) > > > create mode 100644 Documentation/devicetree/bindings/display/bridge/= anx7625.yaml > > > > > > diff --git a/Documentation/devicetree/bindings/display/bridge/anx7625= .yaml b/Documentation/devicetree/bindings/display/bridge/anx7625.yaml > > > new file mode 100644 > > > index 0000000..fc84683 > > > --- /dev/null > > > +++ b/Documentation/devicetree/bindings/display/bridge/anx7625.yaml > > > @@ -0,0 +1,96 @@ > > > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) > > > +# Copyright 2019 Analogix Semiconductor, Inc. > > > +%YAML 1.2 > > > +--- > > > +$id: "http://devicetree.org/schemas/display/bridge/anx7625.yaml#" > > > +$schema: "http://devicetree.org/meta-schemas/core.yaml#" > > > + > > > +title: Analogix ANX7625 SlimPort (4K Mobile HD Transmitter) > > > + > > > +maintainers: > > > + - Xin Ji > > > + > > > +description: | > > > + The ANX7625 is an ultra-low power 4K Mobile HD Transmitter > > > + designed for portable devices. > > > + > > > +properties: > > > + "#address-cells": true > > > + "#size-cells": true > > > + > > > + compatible: > > > + items: > > > + - const: analogix,anx7625 > > > + > > > + reg: > > > + maxItems: 1 > > > + > > > + panel-flags: > > > + description: indicate the panel is internal or external > > > + maxItems: 1 > > > + > > > + interrupts: > > > + maxItems: 1 > > > + > > > + enable-gpios: > > > + description: used for power on chip control, POWER_EN pin D2. > > > + maxItems: 1 > > > + > > > + reset-gpios: > > > + description: used for reset chip control, RESET_N pin B7. > > > + maxItems: 1 > > > + > > > + port@0: > > > + type: object > > > + description: > > > + A port node pointing to MIPI DSI host port node. > > > + > > > + port@1: > > > + type: object > > > + description: > > > + A port node pointing to MIPI DPI host port node. > > > + > > > + port@2: > > > + type: object > > > + description: > > > + A port node pointing to external connector port node. > > > + > > > + port@3: > > > + type: object > > > + description: > > > + A port node pointing to eDP port node. > >=20 > >=20 > > Decrypting available product brief[1], there are following physical lin= es: > >=20 > > Input: > >=20 > > - MIPI DSI/DPI - video data, are DSI and DPI lines shared? >=20 > It would be much easier if we could have access to more complete > information. I believe the DSI and DPI pins could be muxed, but there > should be more DPI pins than DSI pins. Yes DPI pins more than DSI pins. >=20 > >=20 > > - I2S - audio data, > >=20 > > - I2C - control line, > >=20 > > - ALERT/INTP - interrupt, > >=20 > > - USB 3.1 SSRc/Tx - for USB forwarding, > >=20 > > Output: > >=20 > > - SS1, SS2, > >=20 > > - SBU/AUX, > >=20 > > - CC1/2. > >=20 > >=20 > > Having this information I try to understand ports defined by you: > >=20 > > - port@2 you have defined as pointing to external port, but here the > > port should be rather subnode of ANX7625 - the chip has CC lines, see > > beginning of [2]. > >=20 > > - port@3 describes SS1, SS2 and SBU/AUX lines together, am I right? In > > USB-C binding SBU and SS lines are represented by different ports, > > different approach, but maybe better in this case. >=20 > I believe that, when connected to a DP display (either DP or eDP), the > DisplayPort signals are output on SS1 and/or SS2. I this really wonder > if we need two separate ports for this, it seems that port@2 and port@3 > should be merged. OK, I will merge the port@2 and port@3, and use a flag to indicate whether the control is external connector control or not. >=20 > > Maybe it would be good to add 2nd example with USB-C port. >=20 > That would help with the discussion, yes. As we disabled USB-C feature in anx7625, we cannot define a USB-C port. >=20 > > [1]: > > https://www.analogix.com/system/files/AA-002291-PB-6-ANX7625_ProductBri= ef.pdf > >=20 > > [2]: Documentation/devicetree/bindings/connector/usb-connector.txt > >=20 > > > + > > > +required: > > > + - "#address-cells" > > > + - "#size-cells" > > > + - compatible > > > + - reg > > > + - port@0 > > > + - port@3 > > > + > > > +example: > > > + - | > > > + anx7625_bridge: encoder@58 { > > > + compatible =3D "analogix,anx7625"; > > > + reg =3D <0x58>; > > > + status =3D "okay"; > > > + panel-flags =3D <1>; > > > + enable-gpios =3D <&pio 45 GPIO_ACTIVE_HIGH>; > > > + reset-gpios =3D <&pio 73 GPIO_ACTIVE_HIGH>; > > > + #address-cells =3D <1>; > > > + #size-cells =3D <0>; > > > + > > > + port@0 { > > > + reg =3D <0>; > > > + anx_1_in: endpoint { > > > + remote-endpoint =3D <&mipi_dsi>; > > > + }; > > > + }; > > > + > > > + port@3 { > > > + reg =3D <3>; > > > + anx_1_out: endpoint { > > > + remote-endpoint =3D <&panel_in>; > > > + }; > > > + }; > > > + }; >=20 > --=20 > Regards, >=20 > Laurent Pinchart