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. 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"? 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
