On Fri, Jan 25, 2013 at 02:59:28PM +0000, Felipe Balbi wrote: > Hi, > > On Fri, Jan 25, 2013 at 12:29:43PM +0000, Mark Rutland wrote: > > > > > + depending upon omap4 or omap5. > > > > > + - reg-names: The names of the register addresses corresponding to the registers > > > > > + filled in "reg". > > > > > + - ti,type: This is used to differentiate whether the control module has > > > > > + usb mailbox or usb3 phy power. omap4 has usb mailbox in control module to > > > > > + notify events to the musb core and omap5 has usb3 phy power register to > > > > > + power on usb3 phy. Should be "1" if it has mailbox and "2" if it has usb3 > > > > > + phy power. > > > > > > > > Why not make this a string property, perhaps values "mailbox" or "register"? > > > > > > NAK. > > > > Can I ask what your objection to using a string property is? > > > > As far as I can see, "ti,type" is only used by this driver, so there's no > > common convention to stick to. Using a string makes the binding easier for > > humans to read, and thus harder to mess up in a dts, and it decouples the > > binding from kernel-side constants. > > IIRC there is some work going on to add #define-like support for DT, > which would allow us to match against integers while still having > meaningful symbolic representations. I was under the impression that the motivation for using the preprocessor on the DT was to allow symbolic names for device/soc-specific values like addresses, rather than what amounts to ABI values for the binding. I don't see the point in building a binding that depends on future functionality to be legible, especially as we can make it more readable, robust, and just as extensible today, with a simple change to the proposed binding. Even ignoring the above, the driver isn't doing appropriate sanity checking. If you use a string property, this sanity check is implicit in the parsing -- you've either matched a value you can handle or you haven't. Thanks, Mark. -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
