On Thu, 12 Sep 2019, Harry Wentland <hwent...@amd.com> wrote: > On 2019-09-12 3:47 a.m., Ramalingam C wrote: >> On 2019-09-09 at 15:54:50 +0000, Lakha, Bhawanpreet wrote: >>> Hi all, >>> >>> This is regarding the recent hdcp content type patch that was merged into >>> drm-misc. >>> (https://patchwork.freedesktop.org/patch/320958/?series=57233&rev=11) >>> >>> There are displays on the market that advertise HDCP 2.2 support and will >>> pass authentication and encryption but will then show a >>> corrupted/blue/black screen (the driver cannot detect this). These displays >>> work with HDCP 1.4 without any issues. Due to the large number of >>> HDCP-supporting devices on the market we might not be able to catch them >>> with a blacklist. >>> >>> From the user modes perspective, HDCP1.4 and HDCP2.2 Type0 are the same >>> thing. Meaning that this interface doesn't allow us to force the hdcp >>> version. Due to the problems mentioned above we might want to expose the >>> ability for a user to force an HDCP downgrade to a certain level (e.g. 1.4) >>> in case they experience problems. >>> >>> What are your thoughts? and what would be a good way to deal with it? >> Hi, >> >> As you mentioned, uAPI is designed to be HDCP version agnostic. Kernel >> supposed to exercise the highest version of HDCP supported on panel and >> platform. >> >> As we implement the HDCP spec support, if a device is non-compliant with >> HDCP spec after completing the HDCP authentication, I dont think we need >> to worry about it. >> > > Tell that to our (or your) customers.
Agreed, let's rather not. > In this case an enduser might plug in a bad monitor or TV and be unable > to play protected content. > > What if we add a new enum value to the content_type property that says > "DRM_MODE_HDCP_CONTENT_TYPE_FORCE_14"? In general, I think if the fix is to teach the user to jump through hoops in case the output is not working, it is really not a fix. Would, say, a set top box or a Blu-ray player have a setting to force HDCP 1.4, and a troubleshooting item in the manual to select that if the display does not work? Or would OS X have that? If broken HDCP 2.2 sink support is a widespread problem (is it?), what do other HDCP sources do? If it's a Linux issue, what are we doing wrong or different? BR, Jani. > > Harry > >> In case if you want to track and implement a quirk for it, like not to >> project the HDCP2.2 capability, you can use the receiver id of that panel >> to track it. >> >> Thanks, >> -Ram >>> >>> >>> Thanks, >>> >>> Bhawan > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel -- Jani Nikula, Intel Open Source Graphics Center _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
