On Mon, Feb 14, 2022 at 11:45:17PM +0100, Andreas Kemnade wrote: > Hi Rob, > > On Fri, 11 Feb 2022 09:46:27 -0600 > Rob Herring <robh@xxxxxxxxxx> wrote: > > > On Sun, Feb 06, 2022 at 09:00:11AM +0100, Andreas Kemnade wrote: > > > Add a binding for the Electrophoretic Display Controller found at least > > > in the i.MX6. > > > > The first version was in i.MX50 (I helped design the register > > interface). Is that version compatible? > > > it has some differences, but that could be detected by EPDC_VERSION > register. I do not own such a device, so I cannot fully check. I have > not seen any driver with devicetree for IMX5. For now I am rejecting > anything which has a EPDC version which I cannot check. > > > > The timing subnode is directly here to avoid having display parameters > > > spread all over the plate. > > > > > > Supplies are organized the same way as in the fbdev driver in the > > > NXP/Freescale kernel forks. The regulators used for that purpose, > > > like the TPS65185, the SY7636A and MAX17135 have typically a single bit to > > > start a bunch of regulators of higher or negative voltage with a > > > well-defined timing. VCOM can be handled separately, but can also be > > > incorporated into that single bit. > > > > > > Signed-off-by: Andreas Kemnade <andreas@xxxxxxxxxxxx> > > > --- > > > .../bindings/display/imx/fsl,mxc-epdc.yaml | 159 ++++++++++++++++++ > > > 1 file changed, 159 insertions(+) > > > create mode 100644 Documentation/devicetree/bindings/display/imx/fsl,mxc-epdc.yaml > > > > > > diff --git a/Documentation/devicetree/bindings/display/imx/fsl,mxc-epdc.yaml b/Documentation/devicetree/bindings/display/imx/fsl,mxc-epdc.yaml > > > new file mode 100644 > > > index 000000000000..7e0795cc3f70 > > > --- /dev/null > > > +++ b/Documentation/devicetree/bindings/display/imx/fsl,mxc-epdc.yaml > > > @@ -0,0 +1,159 @@ > > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > > > +%YAML 1.2 > > > +--- > > > +$id: http://devicetree.org/schemas/display/imx/fsl,mxc-epdc.yaml# > > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > > + > > > +title: Freescale i.MX6 EPDC > > > + > > > +maintainers: > > > + - Andreas Kemnade <andreas@xxxxxxxxxxxx> > > > + > > > +description: | > > > + The EPDC is a controller for handling electronic paper displays found in > > > + i.MX6 SoCs. > > > + > > > +properties: > > > + compatible: > > > + enum: > > > + - fsl,imx6sl-epdc > > > + - fsl,imx6sll-epdc > > > > Not compatible with each other? > > > differences are detectable by EPDC_VERSION register, so probably so > problem. NXP/Freescale kernel uses > fsl,imx6dl-epdc > and > fsl,imx7d-epdc (used also by imx6 devices with EPDC_VERSION = 3.0) > in their drivers. > > fsl,imx6dl-epdc > fsl,imx6sl-epdc > fsl,imx6sll-epdc > fsl,imx7d-epdc > in their dtsis. > > But the general rule is to use as less as possible compatible strings > if differences can be probed properly, so only one should be > sufficient? Which one? If you can probe all the differences, then just 'fsl,imx-epdc' is sufficient. Just document that so the next time around I don't forget and tell you it needs to be specific. Rob
