Blob Blame History Raw
From: Nathan Chancellor <natechancellor@gmail.com>
Date: Tue, 22 Oct 2019 10:16:48 -0700
Subject: dmaengine: fsl-dpaa2-qdma: Remove unnecessary local variables in
 DPDMAI_CMD_CREATE macro

Git-commit: 7208474d1c7af9f86dfb1f20bfa2abbe22ad2017
Patch-mainline: v5.5-rc1
References: jsc#SLE-12251

Clang warns:

drivers/dma/fsl-dpaa2-qdma/dpdmai.c:148:25: warning: variable 'cfg' is
uninitialized when used within its own initialization [-Wuninitialized]
        DPDMAI_CMD_CREATE(cmd, cfg);
        ~~~~~~~~~~~~~~~~~~~~~~~^~~~
drivers/dma/fsl-dpaa2-qdma/dpdmai.c:42:24: note: expanded from macro
'DPDMAI_CMD_CREATE'
        typeof(_cfg) (cfg) = (_cfg); \
                      ~~~     ^~~~
1 warning generated.

Looking at the preprocessed source, we can see that this is true.

int dpdmai_create(struct fsl_mc_io *mc_io, u32 cmd_flags,
                  const struct dpdmai_cfg *cfg, u16 *token)
{
        struct fsl_mc_command cmd = { 0 };
        int err;

        cmd.header = mc_encode_cmd_header((((0x90E) << 4) | 0), cmd_flags, 0);
        do {
                typeof(cmd)(cmd) = (cmd);
                typeof(cfg)(cfg) = (cfg);
                ((cmd).params[0] |= mc_enc((8), (8), (cfg)->priorities[0]));
                ((cmd).params[0] |= mc_enc((16), (8), (cfg)->priorities[1]));
        } while (0);

I cannot see a good reason to create another version of cfg when the
parameter one will work perfectly fine and cmd can just be used as is.
Remove them to fix this warning.

Fixes: f2835adf8afb ("dmaengine: fsl-dpaa2-qdma: Add the DPDMAI(Data Path DMA Interface) support")
Link: https://github.com/ClangBuiltLinux/linux/issues/746
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Link: https://lore.kernel.org/r/20191022171648.37732-1-natechancellor@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com>
---
 drivers/dma/fsl-dpaa2-qdma/dpdmai.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/dma/fsl-dpaa2-qdma/dpdmai.c b/drivers/dma/fsl-dpaa2-qdma/dpdmai.c
index f8a1f663145b..f8d22115154a 100644
--- a/drivers/dma/fsl-dpaa2-qdma/dpdmai.c
+++ b/drivers/dma/fsl-dpaa2-qdma/dpdmai.c
@@ -37,10 +37,8 @@ struct dpdmai_rsp_get_tx_queue {
 	((_cmd).params[_param] |= mc_enc((_offset), (_width), _arg))
 
 /* cmd, param, offset, width, type, arg_name */
-#define DPDMAI_CMD_CREATE(_cmd, _cfg) \
+#define DPDMAI_CMD_CREATE(cmd, cfg) \
 do { \
-	typeof(_cmd) (cmd) = (_cmd); \
-	typeof(_cfg) (cfg) = (_cfg); \
 	MC_CMD_OP(cmd, 0, 8,  8,  u8,  (cfg)->priorities[0]);\
 	MC_CMD_OP(cmd, 0, 16, 8,  u8,  (cfg)->priorities[1]);\
 } while (0)
-- 
2.26.2