Quoting Prashant Malani (2022-06-23 11:37:08)
On Thu, Jun 23, 2022 at 11:24 AM Stephen Boyd swboyd@chromium.org wrote:
Quoting Prashant Malani (2022-06-22 10:34:35)
From: Pin-Yen Lin treapking@chromium.org
ITE IT6505 can be used in systems to switch USB Type-C DisplayPort alternate mode lane traffic between 2 Type-C ports.
How does it work? From what I can tell from the information I find when googling this part[1] and looking at the existing binding doc is that this device is a DPI to DP bridge, and it outputs DP (probably 4 lanes of it?). Does the 2 type-c port design work by transmitting DP on two lanes of DP for one type-c port and another two lanes of DP for the other type-c port?
DP could be one lane, so if this device is able to output one lane on any output differential pair then I suspect it could support 4 type-c ports if the hardware engineer connected it that way. Can you confirm my suspicion?
I will let Pin-Yen comment re: this hardware, but 1-lane DP is not a supported Type-C Pin assignment (as per VESA DP Alternate Mode Spec version 2.0 [2]), so the H/W
Some missing link?
configuration you are suggesting shouldn't be possible.
Alright, cool. But it is possible in the DP spec. So it seems like if this is connected to 4 DP connectors it could be used to mux between DP on 4 DP ports.