[PATCH 1/5] ARM: Samsung: PWM: Allow to differentiate SoCs based on platform device name.
Kukjin Kim
kgene.kim at samsung.com
Mon Oct 10 05:58:00 EDT 2011
Mark Brown wrote:
>
> On Tue, Sep 06, 2011 at 01:04:30PM +0100, Russell King - ARM Linux wrote:
>
> > Pros to platform driver name:
> > 1. Can re-use existing names if feature compatible without driver mods.
> > 2. Scales well with an increasing number of SoCs.
>
> > Cons:
> > 1. People will hate having SoC names which don't refer to their exact
SoC.
> > 2. Probably requires storage of a set of flags in driver private data
> > to identify SoC specific features.
> > 3. Requires additional string space to identify each driver name.
>
> There's also an issue with actually getting the devices together to
> register which causes fragility here.
>
> > However, thinking about this more wrt DT, there's another aspect to
this.
> > Rather than encoding into the driver "this SoC has features and quirks
> > X,Y,Z" maybe that information should be in the device tree itself. For
> > example, SoC 1 has X and Z, SoC 2 has Y. Then a new SoC 3 comes along
> > with X and Y but not Z. If X, Y, Z are encoded into DT then there's no
> > need to touch the kernel to support SoC 3, not even to change driver
> > names or soc_is_xxx macros etc.
>
> This does depend pretty strongly on making sure that the SoC DT is
> distributed separately to the board DT - that should be solved now.
Yes, I agree. So we can keep the current way to support each SoCs' device
with one driver until DT world.
Thanks.
Best regards,
Kgene.
--
Kukjin Kim <kgene.kim at samsung.com>, Senior Engineer,
SW Solution Development Team, Samsung Electronics Co., Ltd.
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