Internal LVDS Scaling with EDID Panels

The Internal LVDS connected to an EDID Panel supports scaling of modes other than native mode. To support this, the port driver exports information to the EDID parser that it can scale. The EDID parser does not remove other modes (that is, non-native modes) from the mode table. It only marks the native mode. When the Intel^® EMGD queries the port driver on which modes are supported, the port driver then removes any modes that cannot be scaled (up or down depending on the port's hardware capability). When mode-setting occurs, the second display in Clone mode can indeed support non-native modes even though the panel had EDID. This occurs only if a native mode can be found the port driver can scale. Otherwise, the port driver ignores the scaling information and the Intel^® EMGD proceeds normally.

The driver also supports Internal LVDS Scaling on EDID-less panels. The steps that enable this are the same as those described for the scaling of Chrontel LVDS transmitters in Upscaling for the Chrontel CH7308 LVDS Transmitters.