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From:   Ondrej Zary <linux@zary.sk>
To:     Meng Tang <tangmeng@uniontech.com>
Subject: Re: [PATCH] net: 3com: 3c59x: Change the conditional processing for vortex_ioctl
Date:   Thu, 17 Mar 2022 09:00:36 +0100
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On Thursday 17 March 2022, Meng Tang wrote:
> In the vortex_ioctl, there are two places where there can be better
> and easier to understand:
> First, it should be better to reverse the check on 'VORTEX_PCI(vp)'
> and returned early in order to be easier to understand.
> Second, no need to make two 'if(state != 0)' judgments, we can
> simplify the execution process.

Congratulations, you've just added 3 lines of code and broke a driver.
Your "simplified" version does not work with EISA devices.

Why? Please stop "improving" drivers if you can't test them.
 
> Signed-off-by: Meng Tang <tangmeng@uniontech.com>
> ---
>  drivers/net/ethernet/3com/3c59x.c | 15 +++++++++------
>  1 file changed, 9 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/net/ethernet/3com/3c59x.c b/drivers/net/ethernet/3com/3c59x.c
> index ccf07667aa5e..c22de3c8cd12 100644
> --- a/drivers/net/ethernet/3com/3c59x.c
> +++ b/drivers/net/ethernet/3com/3c59x.c
> @@ -3032,16 +3032,19 @@ static int vortex_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
>  	struct vortex_private *vp = netdev_priv(dev);
>  	pci_power_t state = 0;
>  
> -	if(VORTEX_PCI(vp))
> -		state = VORTEX_PCI(vp)->current_state;
> +	if (!VORTEX_PCI(vp))
> +		return -EOPNOTSUPP;
>  
> -	/* The kernel core really should have pci_get_power_state() */
> +	state = VORTEX_PCI(vp)->current_state;
>  
> -	if(state != 0)
> +	/* The kernel core really should have pci_get_power_state() */
> +	if (!state) {
> +		err = generic_mii_ioctl(&vp->mii, if_mii(rq), cmd, NULL);
> +	} else {
>  		pci_set_power_state(VORTEX_PCI(vp), PCI_D0);
> -	err = generic_mii_ioctl(&vp->mii, if_mii(rq), cmd, NULL);
> -	if(state != 0)
> +		err = generic_mii_ioctl(&vp->mii, if_mii(rq), cmd, NULL);
>  		pci_set_power_state(VORTEX_PCI(vp), state);
> +	}
>  
>  	return err;
>  }


-- 
Ondrej Zary