On Tue, 19 Dec 2023 at 22:55, Abel Vesa <abel.vesa@xxxxxxxxxx> wrote: > > Until now, all platform that supported both eDP and DP had different > compatibles for each mode. Using different compatibles for basically > the same IP block but for a different configuration is bad way all > around. There is a new compute platform from Qualcomm that supports > both eDP and DP with the same PHY. So instead of following the old > method, we should allow the mode to be configured from devicetree. > > There has been an off-list discussion on what would be the right way > to pass on the PHY mode information to the driver and it has been > concluded that phy-cells is the way to go. This means that basically > the controller will pass another value (that is, the PHY type) to > its 'phys' DT property. > > For this, we need both the bindings value and the PHY mode value to be > added as well. > > The controller part will follow shortly. But for now, lets see where > this is going. > > There has been another attempt at this here: > https://lore.kernel.org/all/20231122-phy-qualcomm-edp-x1e80100-v3-3-576fc4e9559d@xxxxxxxxxx/ > > Compared to that version, this one uses the phy-cells method and drops > the X1E80100 support. The X1E80100 support will be a separate patchset. After several back and forth discussions, I think that this approach is not correct and not that easy to extend. Instead I'd like to suggest adding a property to the DP controller, which enables eDP behaviour (and thus makes DP driver call phy_set_mode()). Something like this: dp: displayport-controller@ae0000 { compatible = "qcom,sm8000-dp"; /* reg, interrupts, etc */ edp-interface; /* or simpler */ is-edp; }; What do you think? -- With best wishes Dmitry
