Re: [PATCH 03/10] net: ezchip: nps_enet: Fix platform_get_irq's error checking

[arvindY <arvind.yadav.cs@gmail.com>]

On Monday 04 December 2017 10:12 PM, Russell King - ARM Linux wrote:
> On Mon, Dec 04, 2017 at 11:34:48AM -0500, David Miller wrote:
>> From: Russell King - ARM Linux <linux@armlinux.org.uk>
>> Date: Mon, 4 Dec 2017 16:24:47 +0000
>>
>>> On Mon, Dec 04, 2017 at 11:20:49AM -0500, David Miller wrote:
>>>> From: Arvind Yadav <arvind.yadav.cs@gmail.com>
>>>> Date: Sun,  3 Dec 2017 00:56:15 +0530
>>>>
>>>>> The platform_get_irq() function returns negative if an error occurs.
>>>>> zero or positive number on success. platform_get_irq() error checking
>>>>> for zero is not correct. And remove unnecessary check for free_netdev().
>>>>>
>>>>> Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
>>>>> ---
>>>>>   drivers/net/ethernet/ezchip/nps_enet.c | 7 +++----
>>>>>   1 file changed, 3 insertions(+), 4 deletions(-)
>>>>>
>>>>> diff --git a/drivers/net/ethernet/ezchip/nps_enet.c b/drivers/net/ethernet/ezchip/nps_enet.c
>>>>> index 659f1ad..82dc6d0 100644
>>>>> --- a/drivers/net/ethernet/ezchip/nps_enet.c
>>>>> +++ b/drivers/net/ethernet/ezchip/nps_enet.c
>>>>> @@ -623,9 +623,9 @@ static s32 nps_enet_probe(struct platform_device *pdev)
>>>>>   
>>>>>   	/* Get IRQ number */
>>>>>   	priv->irq = platform_get_irq(pdev, 0);
>>>>> -	if (!priv->irq) {
>>>>> +	if (priv->irq <= 0) {
>>>>>   		dev_err(dev, "failed to retrieve <irq Rx-Tx> value from device tree\n");
>>>>> -		err = -ENODEV;
>>>>> +		err = priv->irq ? priv->irq : -ENODEV;
>>>> If platform_get_irq() returns "zero or positive number on success" then this
>>>> test is wrong and should be "if (priv->irq < 0)"
>>>>
>>>> Also, this series is a mix of different kinds of changes.
>>>>
>>>> Please separate out the platform IRQ error checking and just submit exactly
>>>> those changes as a patch series.
>>>>
>>>> The other bug fixes should be submitted outside of those changes since they
>>>> are unrelated.
>>> The issue of whether IRQ 0 is valid or not has been covered several times
>>> by Linus, and the result is that it is deemed by Linus that IRQ 0 is not
>>> a valid interrupt.
>> Then either platform_get_irq() as defined or this commit message (or both)
>> are wrong.
> Indeed, the commit message is wrong, and that's already been pointed out
> in previous patch sets.
>
I will change commit message.  Commit message will be
  " The platform_get_irq() function returns negative if an
error occurs, Zero if No irq found and positive number
on get irq successful. platform_get_irq() error checking for
only zero is not correct."