Increase the scaled image's theorical width/height until we find a configuration that has valid scaling coefficients, up to 102% of the screen's resolution. This makes sure that we can scale from almost every resolution possible at the cost of a very small distorsion. The CRTC_W / CRTC_H are not modified. This algorithm was already in place but would not try to go above the screen's resolution, and as a result would only work if the CRTC_W / CRTC_H were smaller than the screen resolution. It will now try until it reaches 102% of the screen's resolution. Note that this algorithm exists mostly as a band-aid for a missing functionality: it is not possible for userspace to request the closest mode that would encapsulate the provided one, because the GEM buffer is created beforehand. If there was a way to let the kernel tweak the mode, I could write a better algorithm that would result in a better looking picture. Signed-off-by: Paul Cercueil <paul@crapouillou.net> Acked-by: Sam Ravnborg <sam@ravnborg.org> Link: https://patchwork.freedesktop.org/patch/msgid/20201105083905.8780-1-paul@crapouillou.net