The VESA Organization Vendor-Specific Data Block, defined in VESA
DisplayID Standard v2.0, specifies the eDP Multi-SST Operation (MSO)
stream count and segment pixel overlap.
DisplayID v1.3 has Appendix B: DisplayID as an EDID Extension,
describing how DisplayID sections may be embedded in EDID extension
blocks. DisplayID v2.0 does not have such a section, perhaps implying
that DisplayID v2.0 data should not be included in EDID extensions, but
rather in a "pure" DisplayID structure at its own DDC address pair
A4h/A5h, as described in VESA E-DDC Standard v1.3 chapter 3.
However, in practice, displays out in the field have embedded DisplayID
v2.0 data blocks in EDID extensions, including, in particular, some eDP
MSO displays, where a pure DisplayID structure is not available at all.
Parse the MSO data from the DisplayID data block. Do it as part of
drm_add_display_info(), extending it to parse also DisplayID data to
avoid requiring extra calls to update the information.
v2: Check for VESA OUI (Ville)
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Acked-by: Maxime Ripard <maxime@cerno.tech>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/73ca2887e7b37880690f5c9ba4594c9cd1170669.1630419362.git.jani.nikula@intel.com
Iterating DisplayID blocks across sections (in EDID extensions) is
unnecessarily complicated for the caller. Implement DisplayID iterators
to go through all blocks in all sections.
Usage example:
const struct displayid_block *block;
struct displayid_iter iter;
displayid_iter_edid_begin(edid, &iter);
displayid_iter_for_each(block, &iter) {
/* operate on block */
}
displayid_iter_end(&iter);
When DisplayID is stored in EDID extensions, the DisplayID sections map
to extensions as described in VESA DisplayID v1.3 Appendix B: DisplayID
as an EDID Extension. This is implemented here.
When DisplayID is stored in its dedicated DDC device 0xA4, according to
VESA E-DDC v1.3, different rules apply for the structure. This is not
implemented here, as we don't currently use it, but the idea is you'd
have a different call for beginning the iteration, for example simply:
displayid_iter_begin(displayid, &iter);
instead of displayid_iter_edid_begin(), and everything else would be
hidden away in the iterator functions.
v2:
- sizeof(struct displayid_block) -> sizeof(*block) (Ville)
- remove __ prefix from displayid_iter_block
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/da3dead1752ab16c061f7bd248ac1a4268f7fefb.1617024940.git.jani.nikula@intel.com
We'll be adding more DisplayID specific functions going forward, so
start off by splitting out a few functions to a separate file.
We don't bother with exporting the functions; at least for now they
should be needed solely within drm.ko.
No functional changes.
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/07942d5011891b8e8f77245c78b34f4af97a9315.1617024940.git.jani.nikula@intel.com
There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Kernel code should
always use “flexible array members”[1] for these cases. The older style of
one-element or zero-length arrays should no longer be used[2].
[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://github.com/KSPP/linux/issues/21
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
DisplayID blocks allow embedding of CEA blocks. The payloads are
identical to traditional top level CEA extension blocks, but the header
is slightly different.
This change allows the CEA parser to find a CEA block inside a DisplayID
block. Additionally, it adds support for parsing the embedded CTA
header. No further changes are necessary due to payload parity.
This change fixes audio support for the Valve Index HMD.
Signed-off-by: Andres Rodriguez <andresx7@gmail.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: <stable@vger.kernel.org> # v4.15
Signed-off-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190619180901.17901-1-andresx7@gmail.com
The tiled 5K Dell monitor appears to be hiding it's tiled mode
inside the displayid timings block, this patch parses this
blocks and adds the modes to the modelist.
v1.1: add missing __packed.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=95207
Signed-off-by: Dave Airlie <airlied@redhat.com>
