[PATCH 3/7] usb: gadget: pxa25x_udc: use readl/writel for mmio

Robert Jarzmik robert.jarzmik at free.fr
Fri Jan 29 02:17:01 PST 2016


Arnd Bergmann <arnd at arndb.de> writes:

> This converts the pxa25x udc driver to use readl/writel as normal
> driver should do, rather than dereferencing __iomem pointers
> themselves.
>
> Based on the earlier preparation work, we can now also pass
> the register start in the device pointer so we no longer need
> the global variable.
>
> The unclear part here is for IXP4xx, which supports both big-endian
> and little-endian configurations. So far, the driver has done
> no byteswap in either case. I suspect that is wrong and it would
> actually need to swap in one or the other case, but I don't know
> which. It's also possible that there is some magic setting in
> the chip that makes the endianess of the MMIO register match the
> CPU, and in that case, the code actually does the right thing
> for all configurations, both before and after this patch.
>
> Signed-off-by: Arnd Bergmann <arnd at arndb.de>
For pxa25x_udc:
Acked-by: Robert Jarzmik <robert.jarzmik at free.fr>

Cheers.

--
Robert



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