On 17/07/17 11:05, Russell King - ARM Linux wrote:

On Mon, Jul 17, 2017 at 10:56:47AM +0200, Hans Verkuil wrote:

quoted

Hi Russell,

On 09/06/17 16:10, Russell King - ARM Linux wrote:

quoted

On Fri, Jun 09, 2017 at 03:56:39PM +0200, Neil Armstrong wrote:

quoted

Yes, but on the Amlogic Meson plarform, the DW-HDMI CEC controller is
not used, but a custom one, so this notifier is actually useful for
this platform and maybe others.

Is the CEC controller configured into dw-hdmi (is the config bit set?)
I'm just wondering if we're going to end up with two CEC drivers trying
to bind to the same notifier.

quoted

Should we really wait until I push the Amlogic AO CEC driver ? Having a
notifier in the DW-HDMI driver won't harm anybody since it *will be used*.

It sounds like this adds additional information that has been missing
from the review of my patches - and I suspect changes Hans' comments.
So, I'll wait, it seems pointless to try and update the patches when
it's not clear how to proceed due to other dependencies, especially
when it means that their existing state is what's required (I'm pleased
that I've held off modifying the patches so far.)

If that means having to wait another kernel revision, then I guess that's
what will have to happen.

Can you respin your patch series, keeping the notifier support? The CEC
kernel config handling has been cleaned up (just select CEC_CORE and
CEC_NOTIFIER) so you should be good to go.

Not yet - the change to the way you're dealing with Kconfig in CEC is
fundamentally broken, and needs fixing before we can merge dw-hdmi-cec
support.

As a result of these Kconfig changes, dw-hdmi-cec now fails if:

1. You build the CEC part as a module
2. You build the HDMI part into the kernel

This results in CEC_NOTIFIER=y and CEC_CORE=m, which, when the HDMI part
gets built, results in the stubs in the notifier code being used, rather
than the real functions.  This in turn causes the CEC part to never
receive a physical address, which is therefore non-functional.

I did have a patch to fix this, but it was never committed, and I got
busy with other stuff (so it ended up being git reset --hard away.)

This is more a DRM_DW_HDMI issue than a CEC issue IMHO.

This will fix this:

config DRM_DW_HDMI
        tristate
        select DRM_KMS_HELPER
        select REGMAP_MMIO
        select CEC_CORE if CEC_NOTIFIER			<<<<<<

config DRM_DW_HDMI_CEC
        tristate "Synopsis Designware CEC interface"
        depends on DRM_DW_HDMI
        select CEC_CORE
        select CEC_NOTIFIER
        help
          Support the CE interface which is part of the Synopsis
          Designware HDMI block.

This makes sense: if DRM_DW_HDMI_CEC is disabled but another CEC module is
used instead (as is apparently the case for amlogic), then the

	select CEC_CORE if CEC_NOTIFIER

line ensures that CONFIG_CEC_CORE has the right m/y value.

Regards,

	Hans

PS: Sorry for the empty reply earlier: I accidentally pressed 'Send' too soon :-)