[PATCH v3 1/3] usb: fsl-mxc-udc: replace cpu_is_xxx() with platform_device_id

Felipe Balbi balbi at ti.com
Mon Jan 14 12:40:54 EST 2013


Hi,

On Mon, Jan 14, 2013 at 08:56:33PM +0800, Peter Chen wrote:

<snip>

> > > Usually there isn't any Changelog between IP cores used in the different
> > > fsl processors (at least available outside of fsl), that makes it quite
> > > difficult to say if something found on one imx is really the same as on
> > > the other one. And they (usually) don't provide any versioning
> > > information in a register or the documentation.
> > > 
> > > just my 2¢
> > 
> > $SUBJECT is trying to differentiate a single feature (or maybe two) to
> > replace cpu_is_xxx(), then expose that on driver_data without creating
> > one enum value for each release from fsl.
> 
> Felipe, every one or two SoCs may have their special operations for
> integrate PHY interface, clk operation, or workaround for IC
> limitation.

the particular PHY and clk used should be hidden by phy layer and clk
API respectively. Workarounds, fair enough, we need to handle them; but
ideally those should be based on runtime revision detection, not some
hackery using driver_data.

> Maybe, it will add more future or SoCs (maybe not for this driver) in
> the future, using enum is easier than string comparison for expanding
> something.

a) I never told you to *not* use enum. I said that creating DEVICE_A,
DEVICE_B, DEVICE_C, DEVICE_D and DEVICE_E values when DEVICE_B,
DEVICE_C and DEVICE_E behave exactly the same is unnecessary.

b) you can't be expecting to add future SoCs support to fsl udc, I have
already said and will repeat for the last time: move to chipidea ASAP.

New SoCs cannot be added to fsl udc, you *must* use chipidea for
anything new and move the legacy to chipidea eventually. I will wait for
a full year for you to do that, but after that I will have to start
deleting drivers for the sake of avoid duplication of effort.

cheers

-- 
balbi
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