On Wed, Mar 23, 2022 at 12:11:50PM +0200, Jani Nikula wrote:
On Thu, 17 Mar 2022, Lee Shawn C shawn.c.lee@intel.com wrote:
According to HDMI 2.1 spec.
"The HDMI Forum EDID Extension Override Data Block (HF-EEODB) is utilized by Sink Devices to provide an alternate method to indicate an EDID Extension Block count larger than 1, while avoiding the need to present a VESA Block Map in the first E-EDID Extension Block."
It is a mandatory for HDMI 2.1 protocol compliance as well. This patch help to know how many HF_EEODB blocks report by sink and read allo HF_EEODB blocks back.
It still just boggles my mind that they've implemented something like this. They cite avoiding the EDID Block Map as the rationale... but it's been optional since E-EDID structure v1.4, published in 2006. 15+ years ago.
Can anyone tell me a sane reason for this? What does it provide that E-EDID 1.4 does not? Do they want to use E-EDID v1.3 with this? Why?
Looks to be pretty much the same approach as the DPCD extended receiver cap mess we already have to deal with.
So I presume this is a hack to avoid breaking some garbage source devices that explode when they see too many extension blocks, or something along those lines.