From: Hermes Wu <hermes...@ite.com.tw>

Fix a typo where V compare incorrectly compares av[] with av[] itself,
which can result in HDCP failure.

The loop of V compare is expected to iterate for 5 times
which compare V array form av[0][] to av[4][].
It should check loop counter reach the last statement "i == 5"
before return true

Fixes: 0989c02c7a5c ("drm/bridge: it6505: fix HDCP CTS compare V matching")
Signed-off-by: Hermes Wu <hermes...@ite.com.tw>
---
Changes in v4:
- Fix a typo where V compare incorrectly compares av[] with av[] itself
- Link to v3: 
https://lore.kernel.org/r/20250109-fix-hdcp-v-comp-v3-1-1258edb24...@ite.com.tw

Changes in v3:
- The V value compare loop from i = 0 to i = 4 and shall exit with i == 5 
  if all V element matches
- Link to v2: 
https://lore.kernel.org/r/20250109-fix-hdcp-v-comp-v2-1-7dce0a595...@ite.com.tw

Changes in v2:
- pull the check of statment "i" out of V value check loop 
- Link to v1: 
https://lore.kernel.org/r/20250108-fix-hdcp-v-comp-v1-1-940481182...@ite.com.tw
---
 drivers/gpu/drm/bridge/ite-it6505.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/bridge/ite-it6505.c 
b/drivers/gpu/drm/bridge/ite-it6505.c
index 
88ef76a37fe6accacdd343839ff2569b31b18ceb..76dabca04d0d191b3bdee23c6a3e55f4b6d3bad4
 100644
--- a/drivers/gpu/drm/bridge/ite-it6505.c
+++ b/drivers/gpu/drm/bridge/ite-it6505.c
@@ -2250,12 +2250,13 @@ static bool it6505_hdcp_part2_ksvlist_check(struct 
it6505 *it6505)
                        continue;
                }
 
-               for (i = 0; i < 5; i++) {
+               for (i = 0; i < 5; i++)
                        if (bv[i][3] != av[i][0] || bv[i][2] != av[i][1] ||
-                           av[i][1] != av[i][2] || bv[i][0] != av[i][3])
+                           bv[i][1] != av[i][2] || bv[i][0] != av[i][3])
                                break;
 
-                       DRM_DEV_DEBUG_DRIVER(dev, "V' all match!! %d, %d", 
retry, i);
+               if (i == 5) {
+                       DRM_DEV_DEBUG_DRIVER(dev, "V' all match!! %d", retry);
                        return true;
                }
        }

---
base-commit: 938fbb16aba8f7b88e0fdcf56f315a5bbad41aad
change-id: 20250107-fix-hdcp-v-comp-3ba8e3d7adf3

Best regards,
-- 
Hermes Wu <hermes...@ite.com.tw>


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