[PATCH] ata: libahci_platform: Remove abundant check

[PATCH] ata: libahci_platform: Remove abundant check

[Jiasheng Jiang]

It can be found that platform_get_irq() returns nagative code but not
null when fails.
The comment of the platform_get_irq clearly shows that.
Therefore it should be better to remove the useless check.

Fixes: fd990556f0fa ("ata: move library code from ahci_platform.c to libahci_platform.c")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
---
 drivers/ata/libahci_platform.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/ata/libahci_platform.c b/drivers/ata/libahci_platform.c
index b2f552088291..5ec68f138c28 100644
--- a/drivers/ata/libahci_platform.c
+++ b/drivers/ata/libahci_platform.c
@@ -587,8 +587,6 @@ int ahci_platform_init_host(struct platform_device *pdev,
 			dev_err(dev, "no irq\n");
 		return irq;
 	}
-	if (!irq)
-		return -EINVAL;
 
 	hpriv->irq = irq;
 
-- 
2.25.1

Re: [PATCH] ata: libahci_platform: Remove abundant check

[Damien Le Moal]

On 12/22/21 16:24, Jiasheng Jiang wrote:
> It can be found that platform_get_irq() returns nagative code but not
> null when fails.
> The comment of the platform_get_irq clearly shows that.
> Therefore it should be better to remove the useless check.

Nope, platform_get_irq() can actually return 0 (the comment for that
function is wrong). So testing for !irq is valid and must be kept.

> 
> Fixes: fd990556f0fa ("ata: move library code from ahci_platform.c to libahci_platform.c")
> Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
> ---
>  drivers/ata/libahci_platform.c | 2 --
>  1 file changed, 2 deletions(-)
> 
> diff --git a/drivers/ata/libahci_platform.c b/drivers/ata/libahci_platform.c
> index b2f552088291..5ec68f138c28 100644
> --- a/drivers/ata/libahci_platform.c
> +++ b/drivers/ata/libahci_platform.c
> @@ -587,8 +587,6 @@ int ahci_platform_init_host(struct platform_device *pdev,
>  			dev_err(dev, "no irq\n");
>  		return irq;
>  	}
> -	if (!irq)
> -		return -EINVAL;
>  
>  	hpriv->irq = irq;
>  


-- 
Damien Le Moal
Western Digital Research

Re: [PATCH] ata: libahci_platform: Remove abundant check

[Damien Le Moal]

On 12/22/21 16:24, Jiasheng Jiang wrote:
> It can be found that platform_get_irq() returns nagative code but not
> null when fails.
> The comment of the platform_get_irq clearly shows that.
> Therefore it should be better to remove the useless check.
> 
> Fixes: fd990556f0fa ("ata: move library code from ahci_platform.c to libahci_platform.c")
> Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>

Another note: please use scripts/get_maintainer.pl to see to whom you
should address patches. This one was not addressed to me.

> ---
>  drivers/ata/libahci_platform.c | 2 --
>  1 file changed, 2 deletions(-)
> 
> diff --git a/drivers/ata/libahci_platform.c b/drivers/ata/libahci_platform.c
> index b2f552088291..5ec68f138c28 100644
> --- a/drivers/ata/libahci_platform.c
> +++ b/drivers/ata/libahci_platform.c
> @@ -587,8 +587,6 @@ int ahci_platform_init_host(struct platform_device *pdev,
>  			dev_err(dev, "no irq\n");
>  		return irq;
>  	}
> -	if (!irq)
> -		return -EINVAL;
>  
>  	hpriv->irq = irq;
>  


-- 
Damien Le Moal
Western Digital Research

Re: [PATCH] ata: libahci_platform: Remove abundant check

[Sergey Shtylyov]

Hello!

On 22.12.2021 10:24, Jiasheng Jiang wrote:

> It can be found that platform_get_irq() returns nagative code but not
> null when fails.

    s/null/zero/?

> The comment of the platform_get_irq clearly shows that.

    This comment still doesn't correspond to reality -- 0 can be returned 
(although this would cause a WARN() call)...

> Therefore it should be better to remove the useless check.

    This patch is correct but premature. I have a (not yet merged) patch:

https://marc.info/?l=linux-kernel&m=163623041902285

    It actually disables reporting IRQ0. Until it's merged we have to filter 
out IRQ0 in the libata drivers as libata treats 0 as an indication of the 
polling mode...

> Fixes: fd990556f0fa ("ata: move library code from ahci_platform.c to libahci_platform.c")
> Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
[...]

MBR, Sergey