[PATCH v2 5/7] crypto: omap-sham: Convert to use pm_runtime API

Kevin Hilman khilman at deeprootsystems.com
Thu Oct 25 20:34:02 EDT 2012


Hi Mark,

"Mark A. Greer" <mgreer at animalcreek.com> writes:

> From: "Mark A. Greer" <mgreer at animalcreek.com>
>
> Convert the omap-sham crypto driver to use the
> pm_runtime API instead of the clk API.
>
> CC: Kevin Hilman <khilman at deeprootsystems.com>
> CC: Paul Walmsley <paul at pwsan.com>
> CC: Dmitry Kasatkin <dmitry.kasatkin at intel.com>
> Signed-off-by: Mark A. Greer <mgreer at animalcreek.com>

I can't pretend to fully understand this driver, It looks like the
current code is doing a bit more fine-grained clock gating, and leaving
the IP clocked only when needed.

The proposed version does a 'get' in probe and a 'put' in remove, which
means the IP will always be enabled (and thus preventing low-power
states), even when it's not in use.

If that's really needed, it should be thoroughly described in the
changelog, otherwise I suggest doing the runtime PM 'get' and 'put' in
roughtly the same spots as the current clk enable/disable which makes
this a more straight-forward conversion.

Kevin



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