[PATCH 2/8 v2] ARM: EXYNOS5: Add machine data for USB 2.0

Arnd Bergmann arnd at arndb.de
Sun Jul 29 09:11:07 EDT 2012

On Saturday 28 July 2012, Vivek Gautam wrote:
> > Can you pleae explain why this is done in the changelog?
> >
> > We try hard to do such mappings from the device driver instead,
> > so I'm surprised that this is necessary fo rthe USB phy.
> >
> We are doing the mapping for device address in the driver, but this memory
> mapping for USB PHY registers that need to be programmed by the software
> is done here. This is similar to what we see for exynos4 also. Is it
> something
> that i can still change? Please suggest.

Yes, I think the USB PHY handling for all exynos chips should be changed
from an ad-hoc method to a more formal device driver. As I commented
in another patch of this series, I think the main problem is that
treat the USB PHY as a property of the "platform", which it really isn't.

We have a bunch of other USB PHY drivers for other platforms that are
inside of the drivers/usb hierarchy. For all I know, there is no formal
USB PHY driver API yet, and it seems that it would be a good idea to
introduce one now, but for now, just move the code to
drivers/usb/phy/ and make it one file per different kind of PHY.


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