[Intel-gfx] [PATCH 2/2] drm/i915/audio: Extend audio sync rate support for DP MST

[Yang, Libin]

>-----Original Message-----
>From: Jani Nikula [mailto:jani.nikula at linux.intel.com]
>Sent: Wednesday, November 30, 2016 11:52 PM
>To: Yang, Libin <libin.yang at intel.com>; intel-gfx at lists.freedesktop.org;
>ville.syrjala at linux.intel.com; Vetter, Daniel <daniel.vetter at intel.com>;
>Pandiyan, Dhinakaran <dhinakaran.pandiyan at intel.com>; Kp, Jeeja
><jeeja.kp at intel.com>; tiwai at suse.de
>Subject: RE: [PATCH 2/2] drm/i915/audio: Extend audio sync rate support for
>DP MST
>
>On Wed, 30 Nov 2016, "Yang, Libin" <libin.yang at intel.com> wrote:
>>>-----Original Message-----
>>>From: Jani Nikula [mailto:jani.nikula at linux.intel.com]
>>>Sent: Wednesday, November 30, 2016 12:34 AM
>>>To: Yang, Libin <libin.yang at intel.com>;
>>>intel-gfx at lists.freedesktop.org; ville.syrjala at linux.intel.com;
>>>Vetter, Daniel <daniel.vetter at intel.com>; Pandiyan, Dhinakaran
>>><dhinakaran.pandiyan at intel.com>; Kp, Jeeja <jeeja.kp at intel.com>;
>>>tiwai at suse.de
>>>Cc: Yang, Libin <libin.yang at intel.com>
>>>Subject: Re: [PATCH 2/2] drm/i915/audio: Extend audio sync rate
>>>support for DP MST
>>>
>>>On Tue, 15 Nov 2016, libin.yang at intel.com wrote:
>>>> From: Libin Yang <libin.yang at intel.com>
>>>>
>>>> This patch extends the support of audio sample rate sync up to DP MST.
>>>>
>>>> Signed-off-by: Libin Yang <libin.yang at intel.com>
>>>> ---
>>>>  drivers/gpu/drm/i915/intel_audio.c | 3 ++-
>>>>  1 file changed, 2 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/drivers/gpu/drm/i915/intel_audio.c
>>>> b/drivers/gpu/drm/i915/intel_audio.c
>>>> index c8a1345..88ed869 100644
>>>> --- a/drivers/gpu/drm/i915/intel_audio.c
>>>> +++ b/drivers/gpu/drm/i915/intel_audio.c
>>>> @@ -807,7 +807,8 @@ static int
>>>i915_audio_component_sync_audio_rate(struct device *kdev, int port,
>>>>  	intel_encoder = get_saved_enc(dev_priv, port, pipe);
>>>>  	if (!intel_encoder || !intel_encoder->base.crtc ||
>>>>  	    (intel_encoder->type != INTEL_OUTPUT_HDMI &&
>>>> -	     intel_encoder->type != INTEL_OUTPUT_DP)) {
>>>> +	     intel_encoder->type != INTEL_OUTPUT_DP &&
>>>> +		 intel_encoder->type != INTEL_OUTPUT_DP_MST)) {
>>>
>>>I think the better option is to make absolutely sure we never store
>>>other kinds of encoders in dev_priv->av_enc_map[pipe] to begin with. I
>>>think that's true already, but please add
>>>
>>>	if (WARN_ON(intel_encoder->type != INTEL_OUTPUT_HDMI &&
>>>		    intel_encoder->type != INTEL_OUTPUT_DP &&
>>>		    intel_encoder->type != INTEL_OUTPUT_DP_MST))
>>>        	return;
>>>
>>>near the beginning of intel_audio_codec_enable(), and remove the type
>>>checks here. This reduces the confusion about different kinds of
>>>checks after calling get_saved_enc().
>>
>> We can't put the check at the beginning of the function.
>> We still need the check in the same place as we need get intel_encoder at
>first.
>
>We do not need to duplicate the checks here if we ensure only good stuff is
>ever put into av_enc_map.

Yes, I agree. I will remove the type judgement.

Regards,
Libin

>
>>
>> Regards,
>> Libin
>>
>>>
>>>BR,
>>>Jani.
>>>
>>>
>>>>  		DRM_DEBUG_KMS("Not valid for port %c\n",
>>>port_name(port));
>>>>  		err = -ENODEV;
>>>>  		goto unlock;
>>>
>>>--
>>>Jani Nikula, Intel Open Source Technology Center
>
>--
>Jani Nikula, Intel Open Source Technology Center