[ANN] HDMI CEC Status Update

[Hans Verkuil]

On 05/30/17 09:21, Neil Armstrong wrote:
> Hi Hans,
> 
> On 05/30/2017 08:53 AM, Hans Verkuil wrote:
>> For those who are interested in HDMI CEC support I made a little status
>> document that I intend to keep up to date:
>>
>> https://hverkuil.home.xs4all.nl/cec-status.txt
>>
>> My goal is to get CEC supported for any mainlined HDMI driver where the hardware
>> supports CEC.
>>
>> If anyone is working on a CEC driver that I don't know already about, just drop
>> me an email so I can update the status.
>>
>> I also started maintaining a list of DisplayPort to HDMI adapters that support
>> CEC. If you have one that works and is not on the list, then please let me know.
>> Seeing /dev/cecX is not enough, some adapters do not connect the CEC pin, so they
>> won't be able to detect any other CEC devices. See the test instructions in the
>> cec-status.txt file on how to make sure the adapter has a working CEC pin. I
>> plan to do some more testing this week, so hopefully the list will expand.
>>
>> Thanks!
>>
>>     Hans
> 
> Following our discussion on IRC,
> I'm working on a CEC driver for the standalone Amlogic CEC Controller that is able
> to wake up the device from Suspend or Power Off mode by passing infos to the FW.

FYI: the Pulse Eight linux driver has similar support. It has to be enabled via a
module option (persistent_config=1).

I have no public API for this, mostly because I would first like to get more information
about how these things are typically implemented in hardware.

Regards,

	Hans

> I initially planned to use the DW-HDMI CEC controller but I recently found out that
> on the Amlogic Meson GX SoCs, the CEC line can be pinmuxed to either an Amlogic custom
> controller or either to a Synopsys IP.
> 
> But it's connected to the Synopsys HDMI-RX controller... so my plan to use Russell's code
> is now dead.
> 
> Anyway, I'll still need to have the CEC notifier suport for DW-HDMI, so I made a rebase/cleanup
> of Russell's driver on 4.12-rc3 :
> https://github.com/superna9999/linux/commits/amlogic/v4.12/rmk-dw-hdmi-cec
> The rebase is aligned on dw-hdmi-i2s to use the bridge read/write ops.
> 
> Neil
>