[PATCH 4/6] drm: scrambling support in drm layer

[Sharma, Shashank]

Regards

Shashank


On 2/2/2017 3:21 PM, Ville Syrjälä wrote:
> On Thu, Feb 02, 2017 at 11:18:51AM +0530, Sharma, Shashank wrote:
>> Regards
>>
>> Shashank
>>
>>
>> On 2/1/2017 10:02 PM, Ville Syrjälä wrote:
>>> On Wed, Feb 01, 2017 at 06:14:39PM +0530, Shashank Sharma wrote:
>>>> HDMI 2.0 spec mandates scrambling for modes with pixel clock higher
>>>> than 340Mhz. This patch adds few new functions in drm layer for
>>>> core drivers to enable/disable scrambling.
>>>>
>>>> This patch adds:
>>>> - A function to detect scrambling support parsing HF-VSDB
>>>> - A function to check scrambling status runtime using SCDC read.
>>>> - Two functions to enable/disable scrambling using SCDC read/write.
>>>> - Few new bools to reflect scrambling support and status.
>>>>
>>>> Signed-off-by: Shashank Sharma <shashank.sharma at intel.com>
>>>> ---
>>>>    drivers/gpu/drm/drm_edid.c  | 131 +++++++++++++++++++++++++++++++++++++++++++-
>>>>    include/drm/drm_connector.h |  24 ++++++++
>>>>    include/drm/drm_edid.h      |   6 +-
>>>>    3 files changed, 159 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
>>>> index 37902e5..f0d940a 100644
>>>> --- a/drivers/gpu/drm/drm_edid.c
>>>> +++ b/drivers/gpu/drm/drm_edid.c
>>>> @@ -37,6 +37,7 @@
>>>>    #include <drm/drm_edid.h>
>>>>    #include <drm/drm_encoder.h>
>>>>    #include <drm/drm_displayid.h>
>>>> +#include <drm/drm_scdc_helper.h>
>>>>    
>>>>    #define version_greater(edid, maj, min) \
>>>>    	(((edid)->version > (maj)) || \
>>>> @@ -3814,6 +3815,132 @@ static void drm_detect_hdmi_scdc(struct drm_connector *connector,
>>>>    	}
>>>>    }
>>>>    
>>>> +static void drm_detect_hdmi_scrambling(struct drm_connector *connector,
>>>> +				 const u8 *hf_vsdb)
>>> That names seems off. Should probably be drm_parse_hdmi_forum_vsdb() or
>>> something.
>> Actually, unlike the last patch set, we are not parsing the whole
>> hf_vsdb, but parsing it only for
>> scrambling status byte (hf_vsdb[5]). But may be I can make it
>> drm_detect_scrambling_from_hfvsdb
>> ot something similar. We will have more hf_vsdb parsing for 3d flags,
>> yuv420_deep_color etc.
> Well, so far I'm not seeing much point in splitting it up. So I'd stuff
> it all into one place, for now at least.
I had published a patch just doing as you suggested which was parsing 
complete hf-vsdb in one shot, and adding info in
hdmi_info structure, to accommodate it.
(Patch https://patchwork.freedesktop.org/patch/128963/ and 
https://patchwork.freedesktop.org/patch/128962/)

But you gave a review comment not to add anything which is not being 
used in the patch series:
https://patchwork.freedesktop.org/patch/128962/

That was the only reason I have split hf-vsdb parsing patch into 3 parts
- parse SCDC and scrambling info (here)
- with YUV420 deep color ( upcoming )
- with 3d handling (upcoming)

So I am confused, split or no split :-) ?

- Shashank