Re: [PATCH v3 14/36] mtd: st_spi_fsm: Add device-tree binding documentation

Lee Jones
2013-12-02T11:03:19Z

> > +Optional properties:
> > + - st,syscfg : Phandle to boot-device system configuration registers
> > + - st,boot-device-reg : Address of the aforementioned boot-device register(s)
> > + - st,boot-device-spi : Expected boot-device value if booted via this device
> > +
> > +Example:
> > + spifsm: spifsm@fe902000{
> > + compatible = "st,spi-fsm";
> > + reg = <0xfe902000 0x1000>;
> > + reg-names = "spi-fsm";
> > + pinctrl-0 = <&pinctrl_fsm>;
> > + st,syscfg = <&syscfg_rear>;
> > + st,boot-device-reg = <0x958>;
> > + st,boot-device-spi = <0x1a>;
>
> I don't think we should encode any register offsets whatsoever in device
> tree but maybe that's just me. (Yes, Stephen will beat me up about
> pin control single, but I consider that a special case.)
>
> I would just put the last two things as #defines into the driver file(s)
> or - if it's related to other syscfg registers and varies with SoC incarnation,
> as a #define in a shared header for that syscfg thing.

No can do. This isn't _this_ device's register offset, this is a
syscfg register offset which a) there is no driver to apply specific
register offsets to and b) are liable to change oversubsequent SoCs.

> The syscfg phandle is elegant though, really like that.

--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
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