linux-kernel - [PATCH 1/1] drm/i915/hdcp: Simplify code in intel_hdcp_auth

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Date:   Thu, 27 May 2021 17:04:21 +0800
From:   Zhen Lei <thunder.leizhen@...wei.com>
To:     Jani Nikula <jani.nikula@...ux.intel.com>,
        Joonas Lahtinen <joonas.lahtinen@...ux.intel.com>,
        Rodrigo Vivi <rodrigo.vivi@...el.com>,
        David Airlie <airlied@...ux.ie>,
        Daniel Vetter <daniel@...ll.ch>,
        intel-gfx <intel-gfx@...ts.freedesktop.org>,
        dri-devel <dri-devel@...ts.freedesktop.org>,
        linux-kernel <linux-kernel@...r.kernel.org>
CC:     Zhen Lei <thunder.leizhen@...wei.com>
Subject: [PATCH 1/1] drm/i915/hdcp: Simplify code in intel_hdcp_auth_downstream()

If intel_hdcp_validate_v_prime() has been successful within the allowed
number of tries, we can directly call drm_dbg_kms() and "goto out" without
jumping out of the loop and repeatedly judging whether the operation is
successful. This can help us reduce an unnecessary if judgment. And it's
a little clearer to read.

No functional change.

Signed-off-by: Zhen Lei <thunder.leizhen@...wei.com>
---
 drivers/gpu/drm/i915/display/intel_hdcp.c | 24 ++++++++++-------------
 1 file changed, 10 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_hdcp.c b/drivers/gpu/drm/i915/display/intel_hdcp.c
index d8570e14fe60..c32a854eda66 100644
--- a/drivers/gpu/drm/i915/display/intel_hdcp.c
+++ b/drivers/gpu/drm/i915/display/intel_hdcp.c
@@ -663,13 +663,13 @@ int intel_hdcp_auth_downstream(struct intel_connector *connector)
 
 	ret = shim->read_ksv_fifo(dig_port, num_downstream, ksv_fifo);
 	if (ret)
-		goto err;
+		goto out;
 
 	if (drm_hdcp_check_ksvs_revoked(&dev_priv->drm, ksv_fifo,
 					num_downstream) > 0) {
 		drm_err(&dev_priv->drm, "Revoked Ksv(s) in ksv_fifo\n");
 		ret = -EPERM;
-		goto err;
+		goto out;
 	}
 
 	/*
@@ -680,20 +680,16 @@ int intel_hdcp_auth_downstream(struct intel_connector *connector)
 		ret = intel_hdcp_validate_v_prime(connector, shim,
 						  ksv_fifo, num_downstream,
 						  bstatus);
-		if (!ret)
-			break;
-	}
-
-	if (i == tries) {
-		drm_dbg_kms(&dev_priv->drm,
-			    "V Prime validation failed.(%d)\n", ret);
-		goto err;
+		if (!ret) {
+			drm_dbg_kms(&dev_priv->drm,
+				    "HDCP is enabled (%d downstream devices)\n",
+				    num_downstream);
+			goto out;
+		}
 	}
 
-	drm_dbg_kms(&dev_priv->drm, "HDCP is enabled (%d downstream devices)\n",
-		    num_downstream);
-	ret = 0;
-err:
+	drm_dbg_kms(&dev_priv->drm, "V Prime validation failed.(%d)\n", ret);
+out:
 	kfree(ksv_fifo);
 	return ret;
 }
-- 
2.25.1