[v2] drm/bridge: it6505: fix HDCP V match check is not performed correctly

Commit Message

Hermes Wu via B4 Relay Jan. 9, 2025, 4:36 a.m. UTC

From: Hermes Wu <[e-mail]>

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 before return true

Fixes: 0989c02c7a5c ("drm/bridge: it6505: fix HDCP CTS compare V matching")
Reviewed-by: Dmitry Baryshkov <[e-mail]>
Signed-off-by: Hermes Wu <[e-mail]>
---
Changes in v2:
- pull the check of statment "i" out of V value check loop 
- Link to v1: https://lore.kernel.org/r/[e-mail]
---
 drivers/gpu/drm/bridge/ite-it6505.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)


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

Best regards,

Patch

diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c
index 88ef76a37fe6accacdd343839ff2569b31b18ceb..a7c33270a2b75d7c8ab85f6165b367a7c1a364a3 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])
 				break;
 
-			DRM_DEV_DEBUG_DRIVER(dev, "V' all match!! %d, %d", retry, i);
+		if (i == 4) {
+			DRM_DEV_DEBUG_DRIVER(dev, "V' all match!! %d", retry);
 			return true;
 		}
 	}