Re: [PATCH 1/3] arm64: dts: rockchip: add bus-width properties to mmc nodes for rk3328.dtsi
From: Heiko Stübner
Date: Tue Apr 21 2020 - 04:37:49 EST
Am Dienstag, 21. April 2020, 10:29:49 CEST schrieb Chen-Yu Tsai:
> On Tue, Apr 21, 2020 at 4:23 PM Heiko Stübner <heiko@xxxxxxxxx> wrote:
> >
> > Hi ChenYu,
> >
> > Am Dienstag, 21. April 2020, 05:48:52 CEST schrieb Chen-Yu Tsai:
> > > On Fri, Apr 17, 2020 at 2:19 AM Johan Jonker <jbx6244@xxxxxxxxx> wrote:
> > > >
> > > > 'bus-width' and pinctrl containing the bus-pins
> > > > should be in the same file, so add them to
> > > > all mmc nodes in 'rk3328.dtsi'.
> > >
> > > Nope. First of all, pinctrl usage is with pinctrl-N properties, not the
> > > pinctrl device, and there are no defaults set for any of the mmc nodes.
> > > Second, these are board design specific. For example, boards are free to
> > > use just 4 bits for the eMMC if they so desire. So this should be in each
> > > board dts file. If a board is missing this property, fix the board.
> >
> > you are correct that the pinctrl entries are missing from the patches,
> > bus-width and pinctrl should be defined in the same file each time,
> > but for the whole idea I tend to disagree.
> >
> > So far every board with a Rockchip socs follows Rockchip's reference design
> > for a lot of parts - for example I only see sdmmc nodes with bus-width=4
> > etc.
> >
> > So the basic idea is to have default pinctrl settings for the settings
> > everybody uses predefined ... if a board comes along that needs different
> > settings it is free to redefine that.
>
> I think having a default is a great idea. :)
especially for controllers that only ever use the same settings anyway.