[Intel-gfx] [PATCH v3 29/40] drm/i915: Pullout the bksv read and validation

[Ramalingam C]

For reusability purpose, this patch implements the hdcp1.4 bksv's
read and validation as a functions.

For detecting the HDMI panel's HDCP capability this fucntions will be
used.

v2:
  Rebased.
v3:
  No Changes.

Signed-off-by: Ramalingam C <ramalingam.c at intel.com>
---
 drivers/gpu/drm/i915/intel_hdcp.c | 38 +++++++++++++++++++++++++-------------
 1 file changed, 25 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_hdcp.c b/drivers/gpu/drm/i915/intel_hdcp.c
index fd30e2b1ddc3..53d35ee8f683 100644
--- a/drivers/gpu/drm/i915/intel_hdcp.c
+++ b/drivers/gpu/drm/i915/intel_hdcp.c
@@ -152,6 +152,27 @@ bool intel_hdcp_is_ksv_valid(u8 *ksv)
 	return true;
 }
 
+static inline
+int intel_hdcp_read_valid_bksv(struct intel_digital_port *intel_dig_port,
+			       const struct intel_hdcp_shim *shim, u8 *bksv)
+{
+	int ret, i, tries = 2;
+
+	/* HDCP spec states that we must retry the bksv if it is invalid */
+	for (i = 0; i < tries; i++) {
+		ret = shim->read_bksv(intel_dig_port, bksv);
+		if (ret)
+			return ret;
+		if (intel_hdcp_is_ksv_valid(bksv))
+			break;
+	}
+	if (i == tries) {
+		DRM_ERROR("HDCP failed, Bksv is invalid\n");
+		return -ENODEV;
+	}
+	return 0;
+}
+
 /* Implements Part 2 of the HDCP authorization procedure */
 static
 int intel_hdcp_auth_downstream(struct intel_digital_port *intel_dig_port,
@@ -411,7 +432,7 @@ static int intel_hdcp_auth(struct intel_digital_port *intel_dig_port,
 	struct drm_i915_private *dev_priv;
 	enum port port;
 	unsigned long r0_prime_gen_start;
-	int ret, i, tries = 2;
+	int ret, i;
 	union {
 		u32 reg[2];
 		u8 shim[DRM_HDCP_AN_LEN];
@@ -469,18 +490,9 @@ static int intel_hdcp_auth(struct intel_digital_port *intel_dig_port,
 
 	memset(&bksv, 0, sizeof(bksv));
 
-	/* HDCP spec states that we must retry the bksv if it is invalid */
-	for (i = 0; i < tries; i++) {
-		ret = shim->read_bksv(intel_dig_port, bksv.shim);
-		if (ret)
-			return ret;
-		if (intel_hdcp_is_ksv_valid(bksv.shim))
-			break;
-	}
-	if (i == tries) {
-		DRM_ERROR("HDCP failed, Bksv is invalid\n");
-		return -ENODEV;
-	}
+	ret = intel_hdcp_read_valid_bksv(intel_dig_port, shim, bksv.shim);
+	if (ret < 0)
+		return ret;
 
 	I915_WRITE(PORT_HDCP_BKSVLO(port), bksv.reg[0]);
 	I915_WRITE(PORT_HDCP_BKSVHI(port), bksv.reg[1]);
-- 
2.7.4