Hi Köry, On Wed Nov 26, 2025 at 6:35 PM CET, Kory Maincent (TI.com) wrote: > The tilcdc hardware does not generate VESA-compliant sync signals. It > aligns the vertical sync (VS) on the second edge of the horizontal sync > (HS) instead of the first edge. To compensate for this hardware > behavior, the driver applies a timing adjustment in mode_fixup(). > > Previously, this adjustment was conditional based on the simulate_vesa_sync > flag, which was only set when using external encoders. This appears > problematic because: > > 1. The timing adjustment seems needed for the hardware behavior regardless > of whether an external encoder is used > 2. The external encoder infrastructure is driver-specific and being > removed due to design issues > 3. Boards using tilcdc without bridges (e.g., am335x-evm, am335x-evmsk) > may not be getting the necessary timing adjustments > > Remove the simulate_vesa_sync flag and apply the VESA sync timing > adjustment unconditionally, ensuring consistent behavior across all > configurations. While it's unclear if the previous conditional behavior > was causing actual issues, the unconditional adjustment better reflects > the hardware's characteristics. > > Signed-off-by: Kory Maincent (TI.com) <[email protected]> > --- > > Only few board currently use tilcdc not associated to a bridge like the > am335x_evm or the am335x-evmsk.
Have you tested this change on any affected board? The change looks good to me but without some testing it would be risky. Luca -- Luca Ceresoli, Bootlin Embedded Linux and Kernel engineering https://bootlin.com
