[PATCH v2] crypto: talitos - Use devm_platform_ioremap_resource()

[PATCH v2] crypto: talitos - Use devm_platform_ioremap_resource()

[Fabio Estevam]

Use devm_platform_ioremap_resource() to simplify the code a bit.

While at it, remove unneeded error message in case of
devm_platform_ioremap_resource() failure, as the core mm code
will take care of it.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
---
Changes since v1:
- Adjust the error check for devm_platform_ioremap_resource()
- Remove error message on devm_platform_ioremap_resource() failure

 drivers/crypto/talitos.c | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/drivers/crypto/talitos.c b/drivers/crypto/talitos.c
index 32a7e747dc5f..688affec36c9 100644
--- a/drivers/crypto/talitos.c
+++ b/drivers/crypto/talitos.c
@@ -3336,7 +3336,6 @@ static int talitos_probe(struct platform_device *ofdev)
 	struct talitos_private *priv;
 	int i, err;
 	int stride;
-	struct resource *res;
 
 	priv = devm_kzalloc(dev, sizeof(struct talitos_private), GFP_KERNEL);
 	if (!priv)
@@ -3350,13 +3349,9 @@ static int talitos_probe(struct platform_device *ofdev)
 
 	spin_lock_init(&priv->reg_lock);
 
-	res = platform_get_resource(ofdev, IORESOURCE_MEM, 0);
-	if (!res)
-		return -ENXIO;
-	priv->reg = devm_ioremap(dev, res->start, resource_size(res));
-	if (!priv->reg) {
-		dev_err(dev, "failed to of_iomap\n");
-		err = -ENOMEM;
+	priv->reg = devm_platform_ioremap_resource(ofdev, 0);
+	if (IS_ERR(priv->reg)) {
+		err = PTR_ERR(priv->reg);
 		goto err_out;
 	}
 
-- 
2.17.1

Re: [PATCH v2] crypto: talitos - Use devm_platform_ioremap_resource()

[Christophe Leroy]

Le 06/06/2019 à 19:28, Fabio Estevam a écrit :
> Use devm_platform_ioremap_resource() to simplify the code a bit.
> 
> While at it, remove unneeded error message in case of
> devm_platform_ioremap_resource() failure, as the core mm code
> will take care of it.

devm_platform_ioremap_resource() doesn't use devm_ioremap() but 
devm_ioremap_ressource() which does an devm_request_mem_region() in 
addition.

Have you checked that it has no impact ?

On SOCs, areas of memory are often shared between several drivers. 
devm_ioremap_ressource() can only be used if we are 100% sure that this 
area of memory is not shared with any other driver.

Christophe

> 
> Signed-off-by: Fabio Estevam <festevam@gmail.com>
> ---
> Changes since v1:
> - Adjust the error check for devm_platform_ioremap_resource()
> - Remove error message on devm_platform_ioremap_resource() failure
> 
>   drivers/crypto/talitos.c | 11 +++--------
>   1 file changed, 3 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/crypto/talitos.c b/drivers/crypto/talitos.c
> index 32a7e747dc5f..688affec36c9 100644
> --- a/drivers/crypto/talitos.c
> +++ b/drivers/crypto/talitos.c
> @@ -3336,7 +3336,6 @@ static int talitos_probe(struct platform_device *ofdev)
>   	struct talitos_private *priv;
>   	int i, err;
>   	int stride;
> -	struct resource *res;
>   
>   	priv = devm_kzalloc(dev, sizeof(struct talitos_private), GFP_KERNEL);
>   	if (!priv)
> @@ -3350,13 +3349,9 @@ static int talitos_probe(struct platform_device *ofdev)
>   
>   	spin_lock_init(&priv->reg_lock);
>   
> -	res = platform_get_resource(ofdev, IORESOURCE_MEM, 0);
> -	if (!res)
> -		return -ENXIO;
> -	priv->reg = devm_ioremap(dev, res->start, resource_size(res));
> -	if (!priv->reg) {
> -		dev_err(dev, "failed to of_iomap\n");
> -		err = -ENOMEM;
> +	priv->reg = devm_platform_ioremap_resource(ofdev, 0);
> +	if (IS_ERR(priv->reg)) {
> +		err = PTR_ERR(priv->reg);
>   		goto err_out;
>   	}
>   
> 

Re: [PATCH v2] crypto: talitos - Use devm_platform_ioremap_resource()

[Fabio Estevam]

Hi Christophe,

On Thu, Jun 6, 2019 at 2:45 PM Christophe Leroy <christophe.leroy@c-s.fr> wrote:

> Have you checked that it has no impact ?
>
> On SOCs, areas of memory are often shared between several drivers.
> devm_ioremap_ressource() can only be used if we are 100% sure that this
> area of memory is not shared with any other driver.

Thanks for the clarification. I think we should stay on the safe side
and discard this patch then.