From: Dave Airlie airlied@redhat.com
We need to use this for validating modeline additions.
Signed-off-by: Dave Airlie airlied@redhat.com --- drivers/gpu/drm/drm_edid.c | 45 +++++++++++++++++++++++++++------------------ 1 file changed, 27 insertions(+), 18 deletions(-)
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index e4c681f..e85d828 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -3901,6 +3901,30 @@ static void drm_add_display_info(struct edid *edid, info->color_formats |= DRM_COLOR_FORMAT_YCRCB422; }
+static int validate_displayid(u8 *displayid, int length, int idx) +{ + int i; + u8 csum = 0; + struct displayid_hdr *base; + + base = (struct displayid_hdr *)&displayid[idx]; + + DRM_DEBUG_KMS("base revision v%d.%d, edid length %d, bytes %d, prod_id %d ext_count %d\n", + base->ver, base->rev, length, base->bytes, base->prod_id, + base->ext_count); + + if (base->bytes + 5 > length - idx) + return -EINVAL; + for (i = idx; i <= base->bytes + 5; i++) { + csum += displayid[i]; + } + if (csum) { + DRM_ERROR("DisplayID checksum invalid, remainder is %d\n", csum); + return -EINVAL; + } + return 0; +} + /** * drm_add_edid_modes - add modes from EDID data, if available * @connector: connector we're probing @@ -4212,30 +4236,15 @@ static int drm_parse_display_id(struct drm_connector *connector, { /* if this is an EDID extension the first byte will be 0x70 */ int idx = 0; - struct displayid_hdr *base; struct displayid_block *block; - u8 csum = 0; - int i; int ret;
if (is_edid_extension) idx = 1;
- base = (struct displayid_hdr *)&displayid[idx]; - - DRM_DEBUG_KMS("base revision v%d.%d, edid length %d, bytes %d, prod_id %d ext_count %d\n", - base->ver, base->rev, length, base->bytes, base->prod_id, base->ext_count); - - if (base->bytes + 5 > length - idx) - return -EINVAL; - - for (i = idx; i <= base->bytes + 5; i++) { - csum += displayid[i]; - } - if (csum) { - DRM_ERROR("DisplayID checksum invalid, remainder is %d\n", csum); - return -EINVAL; - } + ret = validate_displayid(displayid, length, idx); + if (ret) + return ret;
idx += sizeof(struct displayid_hdr); while (block = (struct displayid_block *)&displayid[idx],