Re: [PATCH 9/9] media: dwc: dw-hdmi-rx: Add support for CEC

From: Hans Verkuil
Date: Wed Jun 02 2021 - 14:27:54 EST


On 02/06/2021 20:20, Nelson Costa wrote:
> Hi Hans,
>
> Thanks for your comments and feedback!
>
> From: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
> Date: qua, jun 02, 2021 at 13:45:45
>
>> On 02/06/2021 13:24, Nelson Costa wrote:
>>> @@ -3194,10 +3428,29 @@ static int dw_hdmi_rx_probe(struct platform_device *pdev)
>>> if (ret)
>>> goto err_phy_exit;
>>>
>>> + /* CEC */
>>> +#if IS_ENABLED(CONFIG_VIDEO_DWC_HDMI_RX_CEC)
>>> + dw_dev->cec_adap = cec_allocate_adapter(&dw_hdmi_cec_adap_ops,
>>> + dw_dev, dev_name(dev),
>>> + (CEC_CAP_DEFAULTS |
>>> + CEC_CAP_NEEDS_HPD |
>>
>> This cap makes no sense for a receiver.
>>
>
> This cap was added in order to overcome a scenario that we have when
> there
> was an hot plug. The driver performs a main reset that cause the loss of
> cec controller configuration. And in that case in order to reconfigure

What do you mean with 'there was an hot plug'? Are you talking about the HPD
signal? Or when a new source/cable is connected? Can you point to the code
where that happens in the driver?

Regards,

Hans

> the
> cec this cap was added. Because whenever there is a reset the physical
> address is reconfigured (invalidated and set) and with this cap the cec
> configuration callback function (adap_enable) is called again allowing to
> reconfigure the cec.
>
> Does it make sense?
>
> If not, what should be the best approach in order to deal with this
> scenario?