From: Hermes Wu <Hermes.wu@xxxxxxxxxx>
When HDCP negotiation with a repeater device.
Checking SHA V' matching must retry 3 times before restarting HDCP.
Signed-off-by: Hermes Wu <Hermes.wu@xxxxxxxxxx>
---
drivers/gpu/drm/bridge/ite-it6505.c | 32 +++++++++++++++++++-------------
1 file changed, 19 insertions(+), 13 deletions(-)
diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c
index 40fb47f4954331d63681066fb3af19f0f57bb929..439cca455ecf91b5f83b0add416db7f099f9a34d 100644
--- a/drivers/gpu/drm/bridge/ite-it6505.c
+++ b/drivers/gpu/drm/bridge/ite-it6505.c
@@ -2057,7 +2057,7 @@ static bool it6505_hdcp_part2_ksvlist_check(struct it6505 *it6505)
{
struct device *dev = it6505->dev;
u8 av[5][4], bv[5][4];
- int i, err;
+ int i, err, retry;
i = it6505_setup_sha1_input(it6505, it6505->sha1_input);
if (i <= 0) {
@@ -2066,22 +2066,28 @@ static bool it6505_hdcp_part2_ksvlist_check(struct it6505 *it6505)
}
it6505_sha1_digest(it6505, it6505->sha1_input, i, (u8 *)av);
+ /*1B-05 V' must retry 3 times */
+ for (retry = 0; retry < 3; retry++) {
+ err = it6505_get_dpcd(it6505, DP_AUX_HDCP_V_PRIME(0), (u8 *)bv,
+ sizeof(bv));
- err = it6505_get_dpcd(it6505, DP_AUX_HDCP_V_PRIME(0), (u8 *)bv,
- sizeof(bv));
+ if (err < 0) {
+ dev_err(dev, "Read V' value Fail %d", retry);
+ continue;
+ }
- if (err < 0) {
- dev_err(dev, "Read V' value Fail");
- return false;
- }
+ 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;
- for (i = 0; i < 5; i++)
- if (bv[i][3] != av[i][0] || bv[i][2] != av[i][1] ||
- bv[i][1] != av[i][2] || bv[i][0] != av[i][3])
- return false;
+ DRM_DEV_DEBUG_DRIVER(dev, "V' all match!! %d, %d", retry, i);
+ return true;
+ }
+ }
- DRM_DEV_DEBUG_DRIVER(dev, "V' all match!!");
- return true;
+ DRM_DEV_DEBUG_DRIVER(dev, "V' NOT match!! %d", retry);
+ return false;
}
static void it6505_hdcp_wait_ksv_list(struct work_struct *work)
--
2.34.1
