[PATCH v5 05/10] drm/bridge: it6505: fix HDCP Bstatus check

From: Hermes Wu
Date: Tue Oct 01 2024 - 02:45:28 EST


From: Hermes Wu <Hermes.wu@xxxxxxxxxx>

When HDCP is activated,
a DisplayPort source receiving CP_IRQ from the sink
shall check Bstatus from DPCD and process the corresponding value

Signed-off-by: Hermes Wu <Hermes.wu@xxxxxxxxxx>
---
drivers/gpu/drm/bridge/ite-it6505.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c
index dde45e9b0f20..0591715c53f7 100644
--- a/drivers/gpu/drm/bridge/ite-it6505.c
+++ b/drivers/gpu/drm/bridge/ite-it6505.c
@@ -2322,14 +2322,20 @@ static int it6505_process_hpd_irq(struct it6505 *it6505)
DRM_DEV_DEBUG_DRIVER(dev, "dp_irq_vector = 0x%02x", dp_irq_vector);

if (dp_irq_vector & DP_CP_IRQ) {
- it6505_set_bits(it6505, REG_HDCP_TRIGGER, HDCP_TRIGGER_CPIRQ,
- HDCP_TRIGGER_CPIRQ);
-
bstatus = it6505_dpcd_read(it6505, DP_AUX_HDCP_BSTATUS);
if (bstatus < 0)
return bstatus;

DRM_DEV_DEBUG_DRIVER(dev, "Bstatus = 0x%02x", bstatus);
+
+ /*check BSTATUS when recive CP_IRQ */
+ if (bstatus & DP_BSTATUS_R0_PRIME_READY &&
+ it6505->hdcp_status == HDCP_AUTH_GOING)
+ it6505_set_bits(it6505, REG_HDCP_TRIGGER, HDCP_TRIGGER_CPIRQ,
+ HDCP_TRIGGER_CPIRQ);
+ else if (bstatus & (DP_BSTATUS_REAUTH_REQ | DP_BSTATUS_LINK_FAILURE) &&
+ it6505->hdcp_status == HDCP_AUTH_DONE)
+ it6505_start_hdcp(it6505);
}

ret = drm_dp_dpcd_read_link_status(&it6505->aux, link_status);
--
2.34.1