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

David Miller
2017-12-04T16:34:54Z

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.