Re: [PATCH v2 -next] net: mediatek: remove set but not used variable 'status'

[David Miller]

From: Mao Wenan 
Date: Mon, 26 Aug 2019 09:31:18 +0800

> Fixes gcc '-Wunused-but-set-variable' warning:
> drivers/net/ethernet/mediatek/mtk_eth_soc.c: In function mtk_handle_irq:
> drivers/net/ethernet/mediatek/mtk_eth_soc.c:1951:6: warning: variable status 
> set but not used [-Wunused-but-set-variable]
> 
> Fixes: 296c9120752b ("net: ethernet: mediatek: Add MT7628/88 SoC support")
> Signed-off-by: Mao Wenan 

Applied to net-next.

Re: [PATCH v2 -next] net: mediatek: remove set but not used variable 'status'

[Stefan Roese]

Hi!

On 26.08.19 09:10, René van Dorst wrote:

Let's add Stefan to the conversation.
He is the author of this commit.


Thanks Rene.
 

Quoting Mao Wenan :


Fixes gcc '-Wunused-but-set-variable' warning:
drivers/net/ethernet/mediatek/mtk_eth_soc.c: In function mtk_handle_irq:
drivers/net/ethernet/mediatek/mtk_eth_soc.c:1951:6: warning:
variable status set but not used [-Wunused-but-set-variable]

Fixes: 296c9120752b ("net: ethernet: mediatek: Add MT7628/88 SoC support")
Signed-off-by: Mao Wenan 
---
  v2: change format of 'Fixes' tag.
  drivers/net/ethernet/mediatek/mtk_eth_soc.c | 2 --
  1 file changed, 2 deletions(-)

diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
index 8ddbb8d..bb7d623 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -1948,9 +1948,7 @@ static irqreturn_t mtk_handle_irq_tx(int irq,
void *_eth)
  static irqreturn_t mtk_handle_irq(int irq, void *_eth)
  {
struct mtk_eth *eth = _eth;
-   u32 status;

-   status = mtk_r32(eth, MTK_PDMA_INT_STATUS);


Hi Stefan,

You added an extra MTK_PDMA_INT_STATUS read in mtk_handle_irq()
Is that read necessary to work properly?


No, its not needed. This read must have "slipped in" from some earlier
patch versions and I forgot to remove it later. Thanks for catching it.

Reviewed-by: Stefan Roese 

Thanks,
Stefan

Re: [PATCH v2 -next] net: mediatek: remove set but not used variable 'status'

[René van Dorst]

Let's add Stefan to the conversation.
He is the author of this commit.

Quoting Mao Wenan :


Fixes gcc '-Wunused-but-set-variable' warning:
drivers/net/ethernet/mediatek/mtk_eth_soc.c: In function mtk_handle_irq:
drivers/net/ethernet/mediatek/mtk_eth_soc.c:1951:6: warning:  
variable status set but not used [-Wunused-but-set-variable]


Fixes: 296c9120752b ("net: ethernet: mediatek: Add MT7628/88 SoC support")
Signed-off-by: Mao Wenan 
---
 v2: change format of 'Fixes' tag.
 drivers/net/ethernet/mediatek/mtk_eth_soc.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c  
b/drivers/net/ethernet/mediatek/mtk_eth_soc.c

index 8ddbb8d..bb7d623 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -1948,9 +1948,7 @@ static irqreturn_t mtk_handle_irq_tx(int irq,  
void *_eth)

 static irqreturn_t mtk_handle_irq(int irq, void *_eth)
 {
struct mtk_eth *eth = _eth;
-   u32 status;

-   status = mtk_r32(eth, MTK_PDMA_INT_STATUS);


Hi Stefan,

You added an extra MTK_PDMA_INT_STATUS read in mtk_handle_irq()
Is that read necessary to work properly?

Greats,

René



if (mtk_r32(eth, MTK_PDMA_INT_MASK) & MTK_RX_DONE_INT) {
if (mtk_r32(eth, MTK_PDMA_INT_STATUS) & MTK_RX_DONE_INT)
mtk_handle_irq_rx(irq, _eth);
--
2.7.4

Re: [PATCH v2 -next] net: mediatek: remove set but not used variable 'status'

[David Miller]

From: Mao Wenan 
Date: Mon, 26 Aug 2019 09:31:18 +0800

> Fixes gcc '-Wunused-but-set-variable' warning:
> drivers/net/ethernet/mediatek/mtk_eth_soc.c: In function mtk_handle_irq:
> drivers/net/ethernet/mediatek/mtk_eth_soc.c:1951:6: warning: variable status 
> set but not used [-Wunused-but-set-variable]
> 
> Fixes: 296c9120752b ("net: ethernet: mediatek: Add MT7628/88 SoC support")
> Signed-off-by: Mao Wenan 

Are you sure the register isn't being read in order to make some
hardware side effect happen?

Have you tested this on effected hardware?

I'm not applying this without definitive answers to these questions.

[PATCH v2 -next] net: mediatek: remove set but not used variable 'status'

[Mao Wenan]

Fixes gcc '-Wunused-but-set-variable' warning:
drivers/net/ethernet/mediatek/mtk_eth_soc.c: In function mtk_handle_irq:
drivers/net/ethernet/mediatek/mtk_eth_soc.c:1951:6: warning: variable status 
set but not used [-Wunused-but-set-variable]

Fixes: 296c9120752b ("net: ethernet: mediatek: Add MT7628/88 SoC support")
Signed-off-by: Mao Wenan 
---
 v2: change format of 'Fixes' tag.
 drivers/net/ethernet/mediatek/mtk_eth_soc.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c 
b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
index 8ddbb8d..bb7d623 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -1948,9 +1948,7 @@ static irqreturn_t mtk_handle_irq_tx(int irq, void *_eth)
 static irqreturn_t mtk_handle_irq(int irq, void *_eth)
 {
struct mtk_eth *eth = _eth;
-   u32 status;
 
-   status = mtk_r32(eth, MTK_PDMA_INT_STATUS);
if (mtk_r32(eth, MTK_PDMA_INT_MASK) & MTK_RX_DONE_INT) {
if (mtk_r32(eth, MTK_PDMA_INT_STATUS) & MTK_RX_DONE_INT)
mtk_handle_irq_rx(irq, _eth);
-- 
2.7.4