Add an iterator abstraction for going through all the EDID blocks.
Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx>
---
drivers/gpu/drm/drm_edid.c | 48 ++++++++++++++++++++++++++++++++++++++
1 file changed, 48 insertions(+)
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 67eaa01f1d7c..6d71b2b77639 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -1599,6 +1599,54 @@ static const void *edid_extension_block_data(const struct edid *edid, int index)
return edid_block_data(edid, index + 1);
}
+/*
+ * EDID base and extension block iterator.
+ *
+ * struct drm_edid_iter iter;
+ * const u8 *block;
+ *
+ * drm_edid_iter_begin(edid, &iter);
+ * drm_edid_iter_for_each(block, &iter) {
+ * // do stuff with block
+ * }
+ * drm_edid_iter_end(&iter);
+ */
+struct drm_edid_iter {
+ const struct edid *edid;
+
+ /* Current block index. */
+ int index;
+};
+
+static void drm_edid_iter_begin(const struct edid *edid,
+ struct drm_edid_iter *iter)
+{
+ memset(iter, 0, sizeof(*iter));
+
+ iter->edid = edid;
+}
+
+static const void *__drm_edid_iter_next(struct drm_edid_iter *iter)
+{
+ const void *block = NULL;
+
+ if (!iter->edid)
+ return NULL;
+
+ if (iter->index < edid_block_count(iter->edid))
+ block = edid_block_data(iter->edid, iter->index++);
+
+ return block;
+}
+
+#define drm_edid_iter_for_each(__block, __iter) \
+ while (((__block) = __drm_edid_iter_next(__iter)))
+
+static void drm_edid_iter_end(struct drm_edid_iter *iter)
+{
+ memset(iter, 0, sizeof(*iter));
+}
+
static const u8 edid_header[] = {
0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00
};
--
2.30.2
