drm/edid: new drm_edid_block_checksum helper function V3
The function will also be used by a later patch, so factor it out.
V2: make raw_edid const, define/declare before first use
V3: fix erroneuos removal of csum variable
Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index a71ed93..2c1d2e4 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -1014,6 +1014,16 @@
MODULE_PARM_DESC(edid_fixup,
"Minimum number of valid EDID header bytes (0-8, default 6)");
+static int drm_edid_block_checksum(const u8 *raw_edid)
+{
+ int i;
+ u8 csum = 0;
+ for (i = 0; i < EDID_LENGTH; i++)
+ csum += raw_edid[i];
+
+ return csum;
+}
+
static bool drm_edid_is_zero(const u8 *in_edid, int length)
{
if (memchr_inv(in_edid, 0, length))
@@ -1035,8 +1045,7 @@
*/
bool drm_edid_block_valid(u8 *raw_edid, int block, bool print_bad_edid)
{
- int i;
- u8 csum = 0;
+ u8 csum;
struct edid *edid = (struct edid *)raw_edid;
if (WARN_ON(!raw_edid))
@@ -1056,8 +1065,7 @@
}
}
- for (i = 0; i < EDID_LENGTH; i++)
- csum += raw_edid[i];
+ csum = drm_edid_block_checksum(raw_edid);
if (csum) {
if (print_bad_edid) {
DRM_ERROR("EDID checksum is invalid, remainder is %d\n", csum);