[PATCH 2/2] ARM: sa1100: Refactor mcp-sa11x0 to use platform resources.

Jochen Friedrich jochen at scram.de
Wed Jan 18 06:30:13 EST 2012


Hi Russell,

>> Accessing some random SoC registers and in the assabet case even board
>> specific registers from device drivers is even worse IMHO. We don't get
>> a clean solution until we have a pinmux/pinctrl device driver owning
>> these peripheral control registers. At least having the setup in the
>> board files avoids a potential race condition accessing PPDR and PPSR
>> registers from multiple drivers.
>
> Yes, but do we really need the exact same code repeated time and time
> again in each different board file?  Could we not have a function which
> sets the pins up for MCP?

Yes, this would be a good idea. One should do the same for the sa1100 
serial driver. Here we even have the bug that the driver unconditionally 
sets up pins for UART1 and 3 no matter what platform devices are present.

> I'm not complaining about this one - the MCCR1 shares its 64K space with
> the peripheral pin controller, and I suspect we won't get to the point
> where that's controlled by a driver.

Why not? gpio-generic should be able to handle the PPC registers out of 
the box.

Thanks,
Jochen



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