Nested structs makes it impossible to extend the nested struct after
extending the base struct. The union acts as a single struct in this
case but the nesting is still an issue. Use pointers to those structs instead
to keep all of them extensible. Only the struct which is applicable for the
signal type is not a null pointer to make sure only valid data is accessed.
Signed-off-by: Sebastian Wick <sebastian.wick@redhat.com>
This is a private function which parses DTDs. This will be useful
in the next commit to parse DTDs from the CTA extension.
Signed-off-by: Simon Ser <contact@emersion.fr>
The extra underscore indicates that it's not a function which is
part of our public API. This will allow the next commit to setup the
linker to export functions based on their name.
Signed-off-by: Simon Ser <contact@emersion.fr>
The spec defines an upper bound for the extension block count,
which means we don't need to dynamically allocate the array. This
simplifies our logic a bit by removing an allocation error codepath.
The array is NULL-terminated, so EDID_MAX_BLOCK_COUNT is suitable
since it's the max number of extension blocks including the base
block, and the array doesn't include the base block.
Signed-off-by: Simon Ser <contact@emersion.fr>
Introduce an opaque struct di_edid to host EDID structures. Add
a function to create a di_edid (with basic size, header and
checksum validation). Add functions to fetch the EDID version and
revision.
This doesn't do much, but hopefully can be used as a fundation.
Signed-off-by: Simon Ser <contact@emersion.fr>