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

[Lee Jones]

> > +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 at 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
Linaro.org │ Open source software for ARM SoCs
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