[PATCH 05/10] ARM: OMAP2+: Disable GPIO softreset for dm81xx

* Tony Lindgren [off-list ref] [151201 16:42]:

* Matthijs van Duin [off-list ref] [151201 16:11]:

quoted

On 2 December 2015 at 00:38, Tony Lindgren [off-list ref] wrote:

quoted

Looks like GPIO softreset status bit on both dm8168 and dm8148
is broken and only goes high initially. After writing to sysc
softreset bit, the resetdone bit never goes high again.

The resetdone bit works fine, but it needs all clocks active to come
up. You're neglecting to enable the debounce clock to the GPIO module:

quoted

# mw.l 0x4818155c 0x2

That should write 0x102 instead.

It seems to work only once based on what I've seen :) If you try it
after it's powered it never works. Could be I'm doing something wrong
of course..

quoted

You can disable the debounce clock after resetting the module if you
don't need it, though I doubt there's any significant power savings
there. (More likely it exists as a separate bit to allow it to stay
enabled even if the module isn't, for wakeup on debounced inputs.)

Hmm I tried setting HWMOD_CONTROL_OPT_CLKS_IN_RESET flag like we
have for many SoCs to enable also sysclk18_ck but no luck. I can
recheck that.

You're right with 0x102 it works, need to debug further.

Thanks,

Tony