[PATCH v3] drm: bridge: synopsys/dw-hdmi: Enable cec clock

[Archit Taneja]

Hi,

On 11/20/2017 06:00 PM, Hans Verkuil wrote:
> I didn't see this merged for 4.15, is it too late to include this?
> All other changes needed to get CEC to work on rk3288 and rk3399 are all merged.

Sorry for the late reply. I was out last week.

Dave recently sent the second pull request for 4.15, so I think it would be hard to get it
in the merge window now. We could target it for the 4.15-rcs since it is preventing the
feature from working. Is it possible to rephrase the commit message a bit so that it's clear
that we need it for CEC to work?

Thanks,
Archit

> 
> Regards,
> 
> 	Hans
> 
> On 10/26/2017 08:19 PM, Pierre-Hugues Husson wrote:
>> The documentation already mentions "cec" optional clock, but
>> currently the driver doesn't enable it.
>>
>> Changes:
>> v3:
>> - Drop useless braces
>>
>> v2:
>> - Separate ENOENT errors from others
>> - Propagate other errors (especially -EPROBE_DEFER)
>>
>> Signed-off-by: Pierre-Hugues Husson <phh at phh.me>
>> ---
>>   drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 25 +++++++++++++++++++++++++
>>   1 file changed, 25 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
>> index bf14214fa464..d82b9747a979 100644
>> --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
>> +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
>> @@ -138,6 +138,7 @@ struct dw_hdmi {
>>   	struct device *dev;
>>   	struct clk *isfr_clk;
>>   	struct clk *iahb_clk;
>> +	struct clk *cec_clk;
>>   	struct dw_hdmi_i2c *i2c;
>>   
>>   	struct hdmi_data_info hdmi_data;
>> @@ -2382,6 +2383,26 @@ __dw_hdmi_probe(struct platform_device *pdev,
>>   		goto err_isfr;
>>   	}
>>   
>> +	hdmi->cec_clk = devm_clk_get(hdmi->dev, "cec");
>> +	if (PTR_ERR(hdmi->cec_clk) == -ENOENT) {
>> +		hdmi->cec_clk = NULL;
>> +	} else if (IS_ERR(hdmi->cec_clk)) {
>> +		ret = PTR_ERR(hdmi->cec_clk);
>> +		if (ret != -EPROBE_DEFER)
>> +			dev_err(hdmi->dev, "Cannot get HDMI cec clock: %d\n",
>> +					ret);
>> +
>> +		hdmi->cec_clk = NULL;
>> +		goto err_iahb;
>> +	} else {
>> +		ret = clk_prepare_enable(hdmi->cec_clk);
>> +		if (ret) {
>> +			dev_err(hdmi->dev, "Cannot enable HDMI cec clock: %d\n",
>> +					ret);
>> +			goto err_iahb;
>> +		}
>> +	}
>> +
>>   	/* Product and revision IDs */
>>   	hdmi->version = (hdmi_readb(hdmi, HDMI_DESIGN_ID) << 8)
>>   		      | (hdmi_readb(hdmi, HDMI_REVISION_ID) << 0);
>> @@ -2518,6 +2539,8 @@ __dw_hdmi_probe(struct platform_device *pdev,
>>   		cec_notifier_put(hdmi->cec_notifier);
>>   
>>   	clk_disable_unprepare(hdmi->iahb_clk);
>> +	if (hdmi->cec_clk)
>> +		clk_disable_unprepare(hdmi->cec_clk);
>>   err_isfr:
>>   	clk_disable_unprepare(hdmi->isfr_clk);
>>   err_res:
>> @@ -2541,6 +2564,8 @@ static void __dw_hdmi_remove(struct dw_hdmi *hdmi)
>>   
>>   	clk_disable_unprepare(hdmi->iahb_clk);
>>   	clk_disable_unprepare(hdmi->isfr_clk);
>> +	if (hdmi->cec_clk)
>> +		clk_disable_unprepare(hdmi->cec_clk);
>>   
>>   	if (hdmi->i2c)
>>   		i2c_del_adapter(&hdmi->i2c->adap);
>>
> 

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