[PATCHv2 7/8] arm: omap: clockdomain: add support for preventing domain transitions

[Tero Kristo]

On Wed, 2012-02-15 at 11:35 -0800, Kevin Hilman wrote:
> Tero Kristo <t-kristo at ti.com> writes:
> 
> > Some clockdomains can't support manual domain transitions triggered by
> > clock framework, and must be prevented from doing so. Added clkdm flag
> > CLKDM_NO_MANUAL_TRANS for doing this.
> >
> > Signed-off-by: Tero Kristo <t-kristo at ti.com>
> > Cc: Paul Walmsley <paul at pwsan.com>
> > Cc: Kevin Hilman <khilman at ti.com>
> 
> Dumb Q: what's the difference between this new flag and CLKDM_CAN_SWSUP?

CAN_SWSUP controls software wakeup / sleep (clktrctrl values 1 and 2),
but it still allows hwsup based transitions during runtime (basically
using values 0 & 3 for the same register.) NO_MANUAL_TRANS prevents
both, but still allows hwauto mode being enabled in the first place.

I was thinking about adding a flag for preventing the autodep disabling
as this was the root cause for the problem I saw, but I wanted to
optimize the _clkdm_clk_hwmod_enable/disable for this case, as the
domain is not going through any transitions.

-Tero