[PATCH 5.4 137/270] drm/bridge: sil_sii8620: initialize return of sii8620_readb

[Greg Kroah-Hartman]

From: Tom Rix <trix@xxxxxxxxxx>

[ Upstream commit 02cd2d3144653e6e2a0c7ccaa73311e48e2dc686 ]

clang static analysis flags this error

sil-sii8620.c:184:2: warning: Undefined or garbage value
  returned to caller [core.uninitialized.UndefReturn]
        return ret;
        ^~~~~~~~~~

sii8620_readb calls sii8620_read_buf.
sii8620_read_buf can return without setting its output
pararmeter 'ret'.

So initialize ret.

Fixes: ce6e153f414a ("drm/bridge: add Silicon Image SiI8620 driver")
Signed-off-by: Tom Rix <trix@xxxxxxxxxx>
Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
Reviewed-by: Andrzej Hajda <a.hajda@xxxxxxxxxxx>
Signed-off-by: Sam Ravnborg <sam@xxxxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20200712152453.27510-1-trix@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/gpu/drm/bridge/sil-sii8620.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/sil-sii8620.c b/drivers/gpu/drm/bridge/sil-sii8620.c
index bd3165ee53541..04431dbac4a4f 100644
--- a/drivers/gpu/drm/bridge/sil-sii8620.c
+++ b/drivers/gpu/drm/bridge/sil-sii8620.c
@@ -177,7 +177,7 @@ static void sii8620_read_buf(struct sii8620 *ctx, u16 addr, u8 *buf, int len)
 
 static u8 sii8620_readb(struct sii8620 *ctx, u16 addr)
 {
-	u8 ret;
+	u8 ret = 0;
 
 	sii8620_read_buf(ctx, addr, &ret, 1);
 	return ret;
-- 
2.25.1