Unverified Commit a5072fc7 authored by Hermes Wu's avatar Hermes Wu Committed by Robert Foss
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drm/bridge: it6505: fix HDCP V match check is not performed correctly 



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: 0989c02c ("drm/bridge: it6505: fix HDCP CTS compare V matching")
Signed-off-by: default avatarHermes Wu <Hermes.wu@ite.com.tw>
Reviewed-by: default avatarDmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: default avatarRobert Foss <rfoss@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20250121-fix-hdcp-v-comp-v4-1-185f45c728dc@ite.com.tw
parent 93c7dd1b

drivers/gpu/drm/bridge/ite-it6505.c

+4 −3
Original line number Diff line number Diff line
@@ -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;

		}

	}