fb: Add buffer map/unmap functions

The current code to manipulate the buffer has the assumption that we can
create an underlying cairo instance.

However, when it comes to supporting various formats, cairo is very limited
so we would need to decouple the buffer access from cairo surfaces.

Let's create a function that allows to map the underlying GEM buffer from
an igt_fb structure, which will then allow use to manipulate as we wish.

Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>

0 files changed, 0 insertions, 0 deletions