Re: [PATCH net-next 2/2] net: dsa: lan9303: Simplify lan9303_xxx_packet_processing() usage

[Egil Hjelmeland]

On 31. juli 2017 16:00, Vivien Didelot wrote:
> Hi Egil,
>
> A few nitpicks below for lan9303_disable_processing.
>
> Egil Hjelmeland <privat@xxxxxxxxxxxxxxxxxx> writes:
>
> >   static int lan9303_disable_processing(struct lan9303 *chip)
> >   {
> > -	int ret;
> > +	int p;
> >   
> > -	ret = lan9303_disable_packet_processing(chip, 0);
> > -	if (ret)
> > -		return ret;
> > -	ret = lan9303_disable_packet_processing(chip, 1);
> > -	if (ret)
> > -		return ret;
> > -	return lan9303_disable_packet_processing(chip, 2);
> > +	for (p = 0; p <= 2; p++) {
>
> Exclusive limits are often prefer, i.e. 'p < 3'.
OK, that can be nice when I later introduce LAN9303_NUM_PORTS = 3.

> > +		int ret;
> > +
> > +		ret = lan9303_disable_packet_processing(chip, p);
> > +		if (ret)
> > +			return ret;
>
> When any non-zero return code means an error, we usually see 'err'
> instead of 'ret'.

But 'ret' is used throughout the rest of the file. Is it not better to
be locally consistent?

> > +	}
>
> blank line before return statments are appreciated.
OK

> > +	return 0;
> >   }
> >   
> >   static int lan9303_check_device(struct lan9303 *chip)
> > @@ -760,7 +761,6 @@ static int lan9303_port_enable(struct dsa_switch *ds, int port,
> >   	/* enable internal packet processing */
> >   	switch (port) {
> >   	case 1:
> > -		return lan9303_enable_packet_processing(chip, port);
>
> Is this deletion intentional? The commit message does not explain this.
>
> When possible, it is appreciated to separate functional from
> non-functional changes. For example one commit adding the loop in
> lan9303_disable_processing and another one to not enable/disable packet
> processing on port 1.

Case fall through, the change is purely non-functional.

You are perhaps thinking of the patch in my first series where I removed
disable of port 0. I have put that on hold. Juergen says that the
mainline driver works out of the box for him. So I will investigate
that problem bit more.


> >   	case 2:
> >   		return lan9303_enable_packet_processing(chip, port);
> >   	default:
> > @@ -779,13 +779,9 @@ static void lan9303_port_disable(struct dsa_switch *ds, int port,
> >   	/* disable internal packet processing */
> >   	switch (port) {
> >   	case 1:
> > -		lan9303_disable_packet_processing(chip, port);
> > -		lan9303_phy_write(ds, chip->phy_addr_sel_strap + 1,
> > -				  MII_BMCR, BMCR_PDOWN);
> > -		break;
> >   	case 2:
> >   		lan9303_disable_packet_processing(chip, port);
> > -		lan9303_phy_write(ds, chip->phy_addr_sel_strap + 2,
> > +		lan9303_phy_write(ds, chip->phy_addr_sel_strap + port,
> >   				  MII_BMCR, BMCR_PDOWN);
> >   		break;
>
> Thanks,
>
>          Vivien
Egil