forked from luck/tmp_suning_uos_patched
Fix wrong assumptions in cea_for_each_detailed_block v2
The current logic misunderstands the spec about CEA 18byte descriptors. First, the spec doesn't state "detailed timing descriptors" but "18 byte descriptors", so any data record could be stored, mixed timings and other data, just as in the standard EDID. Second, the lower four bit of byte 3 of the CEA record do not contain the number of descriptors, but "the total number of DTDs defining native formats in the whole EDID [...], starting with the first DTD in the DTD list (which starts in the base EDID block)." A device can of course support non-native formats. As such the number can't be used to determine n, and the existing code will filter non-timing 18byte descriptors anyway. Signed-off-by: Christian Schmidt <schmidt@digadd.de> Reviewed-by: Adam Jackson <ajax@redhat.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
This commit is contained in:
parent
a0ab734d62
commit
4966b2a935
|
@ -508,25 +508,10 @@ static void
|
|||
cea_for_each_detailed_block(u8 *ext, detailed_cb *cb, void *closure)
|
||||
{
|
||||
int i, n = 0;
|
||||
u8 rev = ext[0x01], d = ext[0x02];
|
||||
u8 d = ext[0x02];
|
||||
u8 *det_base = ext + d;
|
||||
|
||||
switch (rev) {
|
||||
case 0:
|
||||
/* can't happen */
|
||||
return;
|
||||
case 1:
|
||||
/* have to infer how many blocks we have, check pixel clock */
|
||||
for (i = 0; i < 6; i++)
|
||||
if (det_base[18*i] || det_base[18*i+1])
|
||||
n++;
|
||||
break;
|
||||
default:
|
||||
/* explicit count */
|
||||
n = min(ext[0x03] & 0x0f, 6);
|
||||
break;
|
||||
}
|
||||
|
||||
n = (127 - d) / 18;
|
||||
for (i = 0; i < n; i++)
|
||||
cb((struct detailed_timing *)(det_base + 18 * i), closure);
|
||||
}
|
||||
|
|
Loading…
Reference in New Issue
Block a user