Subject: Re: [PATCH] net: usb: pegasus: fixes of set_register(s) return value evaluation;

From: Petko Manolov <[email-masked]>
Date: Fri, 20 Aug 2021 10:08:35 +0300

On 21-08-19 12:34:29, Jakub Kicinski wrote:
> On Thu, 19 Aug 2021 12:05:39 +0300 Petko Manolov wrote:
> >   - restore the behavior in enable_net_traffic() to avoid regressions - Jakub
> >     Kicinski;
> >   - hurried up and removed redundant assignment in pegasus_open() before yet
> >     another checker complains;
> >   - explicitly check for negative value in pegasus_set_wol(), even if
> >     usb_control_msg_send() never return positive number we'd still be in sync
> >     with the rest of the driver style;
> > 
> > Fixes: 8a160e2e9aeb net: usb: pegasus: Check the return value of get_geristers() and friends;
> 
> I guess this is fine but not exactly the preferred format, please see
> Submitting patches.

If the preferred format involves brackets and quotes - so be it.

> > Reported-by: Jakub Kicinski <[email-masked]>
> > Signed-off-by: Petko Manolov <[email-masked]>
> > ---
> >  drivers/net/usb/pegasus.c | 6 +++---
> >  1 file changed, 3 insertions(+), 3 deletions(-)
> > 
> > diff --git a/drivers/net/usb/pegasus.c b/drivers/net/usb/pegasus.c
> > index 652e9fcf0b77..1ef93082c772 100644
> > --- a/drivers/net/usb/pegasus.c
> > +++ b/drivers/net/usb/pegasus.c
> > @@ -446,7 +446,7 @@ static int enable_net_traffic(struct net_device *dev, struct usb_device *usb)
> >  		write_mii_word(pegasus, 0, 0x1b, &auxmode);
> >  	}
> >  
> > -	return 0;
> > +	return ret;
> 
> yup
> 
> >  fail:
> >  	netif_dbg(pegasus, drv, pegasus->net, "%s failed\n", __func__);
> >  	return ret;
> > @@ -835,7 +835,7 @@ static int pegasus_open(struct net_device *net)
> >  	if (!pegasus->rx_skb)
> >  		goto exit;
> >  
> > -	res = set_registers(pegasus, EthID, 6, net->dev_addr);
> > +	set_registers(pegasus, EthID, 6, net->dev_addr);
> 
> yup
> 
> >  	usb_fill_bulk_urb(pegasus->rx_urb, pegasus->usb,
> >  			  usb_rcvbulkpipe(pegasus->usb, 1),
> > @@ -932,7 +932,7 @@ pegasus_set_wol(struct net_device *dev, struct ethtool_wolinfo *wol)
> >  	pegasus->wolopts = wol->wolopts;
> >  
> >  	ret = set_register(pegasus, WakeupControl, reg78);
> > -	if (!ret)
> > +	if (ret < 0)
> >  		ret = device_set_wakeup_enable(&pegasus->usb->dev,
> >  						wol->wolopts);
> 
> now this looks incorrect and unrelated to recent changes (IOW the
> commit under Fixes), please drop this chunk

It may not be related, but the change is:

	a) obviously correct; and

	b) in sync with the rest of 'ret' evaluations;

To be honest i do not envision usb_control_msg_send() returning positive value
anytime soon, but (ret < 0) looks "more" correct than (!ret).

		Petko