Add some helpers to figure out the EDID extension block count, block
count, size, pointers to blocks.
Unfortunately, we'll need to cast away the const in a few places where
we actually need to access the data.
v2: fix s/j/i/ introduced in a rebase
Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx>
---
drivers/gpu/drm/drm_edid.c | 80 +++++++++++++++++++++++++++-----------
1 file changed, 57 insertions(+), 23 deletions(-)
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 90615e30eaf5..c09ff1efdbc8 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -1568,6 +1568,38 @@ static const struct drm_display_mode edid_4k_modes[] = {
/*** DDC fetch and block validation ***/
+static int edid_extension_block_count(const struct edid *edid)
+{
+ return edid->extensions;
+}
+
+static int edid_block_count(const struct edid *edid)
+{
+ return edid_extension_block_count(edid) + 1;
+}
+
+static int edid_size_by_blocks(int num_blocks)
+{
+ return num_blocks * EDID_LENGTH;
+}
+
+static int edid_size(const struct edid *edid)
+{
+ return edid_size_by_blocks(edid_block_count(edid));
+}
+
+static const void *edid_block_data(const struct edid *edid, int index)
+{
+ BUILD_BUG_ON(sizeof(*edid) != EDID_LENGTH);
+
+ return edid + index;
+}
+
+static const void *edid_extension_block_data(const struct edid *edid, int index)
+{
+ return edid_block_data(edid, index + 1);
+}
+
static const u8 edid_header[] = {
0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00
};
@@ -1654,8 +1686,8 @@ bool drm_edid_are_equal(const struct edid *edid1, const struct edid *edid2)
return false;
if (edid1) {
- edid1_len = EDID_LENGTH * (1 + edid1->extensions);
- edid2_len = EDID_LENGTH * (1 + edid2->extensions);
+ edid1_len = edid_size(edid1);
+ edid2_len = edid_size(edid2);
if (edid1_len != edid2_len)
return false;
@@ -1865,14 +1897,16 @@ EXPORT_SYMBOL(drm_edid_block_valid);
bool drm_edid_is_valid(struct edid *edid)
{
int i;
- u8 *raw = (u8 *)edid;
if (!edid)
return false;
- for (i = 0; i <= edid->extensions; i++)
- if (!drm_edid_block_valid(raw + i * EDID_LENGTH, i, true, NULL))
+ for (i = 0; i < edid_block_count(edid); i++) {
+ void *block = (void *)edid_block_data(edid, i);
+
+ if (!drm_edid_block_valid(block, i, true, NULL))
return false;
+ }
return true;
}
@@ -1885,13 +1919,13 @@ static struct edid *edid_filter_invalid_blocks(const struct edid *edid,
int valid_extensions = edid->extensions - invalid_blocks;
int i;
- new = kmalloc_array(valid_extensions + 1, EDID_LENGTH, GFP_KERNEL);
+ new = kmalloc(edid_size_by_blocks(valid_extensions + 1), GFP_KERNEL);
if (!new)
goto out;
dest_block = new;
- for (i = 0; i <= edid->extensions; i++) {
- const void *block = edid + i;
+ for (i = 0; i < edid_block_count(edid); i++) {
+ const void *block = edid_block_data(edid, i);
if (edid_block_valid(block, i == 0))
memcpy(dest_block++, block, EDID_LENGTH);
@@ -2101,7 +2135,7 @@ struct edid *drm_do_get_edid(struct drm_connector *connector,
void *context)
{
enum edid_block_status status;
- int j, invalid_blocks = 0;
+ int i, invalid_blocks = 0;
struct edid *edid, *new;
edid = drm_get_override_edid(connector);
@@ -2133,20 +2167,20 @@ struct edid *drm_do_get_edid(struct drm_connector *connector,
goto fail;
}
- if (edid->extensions == 0)
+ if (!edid_extension_block_count(edid) == 0)
goto ok;
- new = krealloc(edid, (edid->extensions + 1) * EDID_LENGTH, GFP_KERNEL);
+ new = krealloc(edid, edid_size(edid), GFP_KERNEL);
if (!new)
goto fail;
edid = new;
- for (j = 1; j <= edid->extensions; j++) {
- void *block = edid + j;
+ for (i = 1; i < edid_block_count(edid); i++) {
+ void *block = (void *)edid_block_data(edid, i);
- status = edid_block_read(block, j, read_block, context);
+ status = edid_block_read(block, i, read_block, context);
- edid_block_status_print(status, block, j);
+ edid_block_status_print(status, block, i);
if (!edid_block_status_valid(status, edid_block_tag(block))) {
if (status == EDID_BLOCK_READ_FAIL)
@@ -2156,7 +2190,7 @@ struct edid *drm_do_get_edid(struct drm_connector *connector,
}
if (invalid_blocks) {
- connector_bad_edid(connector, edid, edid->extensions + 1);
+ connector_bad_edid(connector, edid, edid_block_count(edid));
edid = edid_filter_invalid_blocks(edid, invalid_blocks);
}
@@ -2321,7 +2355,7 @@ EXPORT_SYMBOL(drm_get_edid_switcheroo);
*/
struct edid *drm_edid_duplicate(const struct edid *edid)
{
- return kmemdup(edid, (edid->extensions + 1) * EDID_LENGTH, GFP_KERNEL);
+ return kmemdup(edid, edid_size(edid), GFP_KERNEL);
}
EXPORT_SYMBOL(drm_edid_duplicate);
@@ -2505,8 +2539,8 @@ drm_for_each_detailed_block(const struct edid *edid, detailed_cb *cb, void *clos
for (i = 0; i < EDID_DETAILED_TIMINGS; i++)
cb(&(edid->detailed_timings[i]), closure);
- for (i = 1; i <= edid->extensions; i++) {
- const u8 *ext = (const u8 *)edid + (i * EDID_LENGTH);
+ for (i = 0; i < edid_extension_block_count(edid); i++) {
+ const u8 *ext = edid_extension_block_data(edid, i);
switch (*ext) {
case CEA_EXT:
@@ -3476,17 +3510,17 @@ const u8 *drm_find_edid_extension(const struct edid *edid,
int i;
/* No EDID or EDID extensions */
- if (edid == NULL || edid->extensions == 0)
+ if (!edid || !edid_extension_block_count(edid))
return NULL;
/* Find CEA extension */
- for (i = *ext_index; i < edid->extensions; i++) {
- edid_ext = (const u8 *)edid + EDID_LENGTH * (i + 1);
+ for (i = *ext_index; i < edid_extension_block_count(edid); i++) {
+ edid_ext = edid_extension_block_data(edid, i);
if (edid_block_tag(edid_ext) == ext_id)
break;
}
- if (i >= edid->extensions)
+ if (i >= edid_extension_block_count(edid))
return NULL;
*ext_index = i + 1;
--
2.30.2
