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From:   Robert Foss <robert.foss@linaro.org>
To:     a.hajda@samsung.com, narmstrong@baylibre.com,
        robert.foss@linaro.org, Laurent.pinchart@ideasonboard.com,
        jonas@kwiboo.se, jernej.skrabec@gmail.com, airlied@linux.ie,
        daniel@ffwll.ch, xji@analogixsemi.com, pihsun@chromium.org,
        tzungbi@google.com, sam@ravnborg.org, hsinyi@chromium.org,
        drinkcat@chromium.org, dri-devel@lists.freedesktop.org,
        linux-kernel@vger.kernel.org
Cc:     kernel test robot <lkp@intel.com>
Subject: [PATCH v2 1/2] drm/bridge: anx7625: Propagate errors from sp_tx_rst_aux()
Date:   Wed, 18 Aug 2021 19:13:17 +0200
Message-Id: <20210818171318.1848272-1-robert.foss@linaro.org>
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The return value of sp_tx_rst_aux() is not propagated, which means
both compiler warnings and potential errors not being handled.

Fixes: 8bdfc5dae4e3 ("drm/bridge: anx7625: Add anx7625 MIPI DSI/DPI to DP")

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Robert Foss <robert.foss@linaro.org>
---

Changes since v1:
 - Instead of discarding the error, propagate it until it
   is handled properly

 drivers/gpu/drm/bridge/analogix/anx7625.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c
index 14d73fb1dd15b..ea414cd349b5c 100644
--- a/drivers/gpu/drm/bridge/analogix/anx7625.c
+++ b/drivers/gpu/drm/bridge/analogix/anx7625.c
@@ -720,7 +720,7 @@ static int edid_read(struct anx7625_data *ctx,
 		ret = sp_tx_aux_rd(ctx, 0xf1);
 
 		if (ret) {
-			sp_tx_rst_aux(ctx);
+			ret = sp_tx_rst_aux(ctx);
 			DRM_DEV_DEBUG_DRIVER(dev, "edid read fail, reset!\n");
 		} else {
 			ret = anx7625_reg_block_read(ctx, ctx->i2c.rx_p0_client,
@@ -735,7 +735,7 @@ static int edid_read(struct anx7625_data *ctx,
 	if (cnt > EDID_TRY_CNT)
 		return -EIO;
 
-	return 0;
+	return ret;
 }
 
 static int segments_edid_read(struct anx7625_data *ctx,
@@ -785,7 +785,7 @@ static int segments_edid_read(struct anx7625_data *ctx,
 	if (cnt > EDID_TRY_CNT)
 		return -EIO;
 
-	return 0;
+	return ret;
 }
 
 static int sp_tx_edid_read(struct anx7625_data *ctx,
@@ -887,7 +887,11 @@ static int sp_tx_edid_read(struct anx7625_data *ctx,
 	}
 
 	/* Reset aux channel */
-	sp_tx_rst_aux(ctx);
+	ret = sp_tx_rst_aux(ctx);
+	if (ret < 0) {
+		DRM_DEV_ERROR(dev, "Failed to reset aux channel!\n");
+		return ret;
+	}
 
 	return (blocks_num + 1);
 }
-- 
2.30.2