For st7789v IC, when we need continuous full screen refresh, it is best to
wait for the tearing effect line signal to arrive to avoid screen tearing.

Signed-off-by: Carlis <zhangxuezhi1@yulong.com>
Link: https://lore.kernel.org/r/1612706517-124617-1-git-send-email-zhangxuezhi3@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>