[PATCH] dma: of-dma: Fix "'nbcells' may be used uninitialized" warning

[PATCH] dma: of-dma: Fix "'nbcells' may be used uninitialized" warning

[Fabio Estevam]

Rearrange the code a bit so that we can get rid of the following build warning:

drivers/dma/of-dma.c:83:15: warning: 'nbcells' may be used uninitialized in this function [-Wuninitialized]

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
---
 drivers/dma/of-dma.c | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/drivers/dma/of-dma.c b/drivers/dma/of-dma.c
index 7aa0864..107e820 100644
--- a/drivers/dma/of-dma.c
+++ b/drivers/dma/of-dma.c
@@ -77,15 +77,14 @@ int of_dma_controller_register(struct device_node *np,
 		return -ENOMEM;
 
 	prop = of_get_property(np, "#dma-cells", NULL);
-	if (prop)
-		nbcells = be32_to_cpup(prop);
+	if (!prop)
+		goto free;
+
+	nbcells = be32_to_cpup(prop);
 
-	if (!prop || !nbcells) {
-		pr_err("%s: #dma-cells property is missing or invalid\n",
-		       __func__);
-		kfree(ofdma);
-		return -EINVAL;
-	}
+
+	if (!nbcells)
+		goto free;
 
 	ofdma->of_node = np;
 	ofdma->of_dma_nbcells = nbcells;
@@ -98,6 +97,11 @@ int of_dma_controller_register(struct device_node *np,
 	mutex_unlock(&of_dma_lock);
 
 	return 0;
+
+free:
+	pr_err("%s: #dma-cells property is missing or invalid\n", __func__);
+	kfree(ofdma);
+	return -EINVAL;
 }
 EXPORT_SYMBOL_GPL(of_dma_controller_register);
 
-- 
1.8.1.2

Re: [PATCH] dma: of-dma: Fix "'nbcells' may be used uninitialized" warning

[Lars-Peter Clausen]

On 05/20/2013 09:17 PM, Fabio Estevam wrote:
> Rearrange the code a bit so that we can get rid of the following build warning:
> 
> drivers/dma/of-dma.c:83:15: warning: 'nbcells' may be used uninitialized in this function [-Wuninitialized]
> 
> Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>

Hi,

I've submitted a patch a couple of weeks ago which removes nbcells
altogether. See: https://patchwork.kernel.org/patch/2470601/

- Lars

> ---
>  drivers/dma/of-dma.c | 20 ++++++++++++--------
>  1 file changed, 12 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/dma/of-dma.c b/drivers/dma/of-dma.c
> index 7aa0864..107e820 100644
> --- a/drivers/dma/of-dma.c
> +++ b/drivers/dma/of-dma.c
> @@ -77,15 +77,14 @@ int of_dma_controller_register(struct device_node *np,
>  		return -ENOMEM;
>  
>  	prop = of_get_property(np, "#dma-cells", NULL);
> -	if (prop)
> -		nbcells = be32_to_cpup(prop);
> +	if (!prop)
> +		goto free;
> +
> +	nbcells = be32_to_cpup(prop);
>  
> -	if (!prop || !nbcells) {
> -		pr_err("%s: #dma-cells property is missing or invalid\n",
> -		       __func__);
> -		kfree(ofdma);
> -		return -EINVAL;
> -	}
> +
> +	if (!nbcells)
> +		goto free;
>  
>  	ofdma->of_node = np;
>  	ofdma->of_dma_nbcells = nbcells;
> @@ -98,6 +97,11 @@ int of_dma_controller_register(struct device_node *np,
>  	mutex_unlock(&of_dma_lock);
>  
>  	return 0;
> +
> +free:
> +	pr_err("%s: #dma-cells property is missing or invalid\n", __func__);
> +	kfree(ofdma);
> +	return -EINVAL;
>  }
>  EXPORT_SYMBOL_GPL(of_dma_controller_register);
>