Re: [PATCH 2/2] net, thunder, bgx: Add support for ACPI binding.

[Tomasz Nowicki]

On 07.08.2015 12:43, Robert Richter wrote:
> On 07.08.15 10:09:04, Tomasz Nowicki wrote:
> > On 07.08.2015 02:33, David Daney wrote:
>
> ...
>
> > > +#else
> > > +
> > > +static int bgx_init_acpi_phy(struct bgx *bgx)
> > > +{
> > > +	return -ENODEV;
> > > +}
> > > +
> > > +#endif /* CONFIG_ACPI */
> > > +
> > >   #if IS_ENABLED(CONFIG_OF_MDIO)
> > >
> > >   static int bgx_init_of_phy(struct bgx *bgx)
> > > @@ -882,7 +1010,12 @@ static int bgx_init_of_phy(struct bgx *bgx)
> > >
> > >   static int bgx_init_phy(struct bgx *bgx)
> > >   {
> > > -	return bgx_init_of_phy(bgx);
> > > +	int err = bgx_init_of_phy(bgx);
> > > +
> > > +	if (err != -ENODEV)
> > > +		return err;
> > > +
> > > +	return bgx_init_acpi_phy(bgx);
> > >   }
> >
> > If kernel can work with DT and ACPI (both compiled in), it should take only
> > one path instead of probing DT and ACPI sequentially. How about:
> >
> > @@ -902,10 +925,9 @@ static int bgx_probe(struct pci_dev *pdev, const struct
> > pci_device_id *ent)
> >   	bgx_vnic[bgx->bgx_id] = bgx;
> >   	bgx_get_qlm_mode(bgx);
> >
> > -	snprintf(bgx_sel, 5, "bgx%d", bgx->bgx_id);
> > -	np = of_find_node_by_name(NULL, bgx_sel);
> > -	if (np)
> > -		bgx_init_of(bgx, np);
> > +	err = acpi_disabled ? bgx_init_of_phy(bgx) : bgx_init_acpi_phy(bgx);
> > +	if (err)
> > +		goto err_enable;
> >
> >   	bgx_init_hw(bgx);
>
> I would not pollute bgx_probe() with acpi and dt specifics, and instead
> keep bgx_init_phy(). The typical design pattern for this is:
>
> static int bgx_init_phy(struct bgx *bgx)
> {
> #ifdef CONFIG_ACPI
>          if (!acpi_disabled)
>                  return bgx_init_acpi_phy(bgx);
> #endif
>          return bgx_init_of_phy(bgx);
> }
>
> This adds acpi runtime detection (acpi=no), does not call dt code in
> case of acpi, and saves the #else for bgx_init_acpi_phy().

I am fine with keeping it in bgx_init_phy(), however we can drop there 
#ifdefs since both of bgx_init_{acpi,of}_phy calls have empty stub for 
!ACPI and !OF case. Like that:

static int bgx_init_phy(struct bgx *bgx)
{

        if (!acpi_disabled)
                return bgx_init_acpi_phy(bgx);
	else
        	return bgx_init_of_phy(bgx);
}

Tomasz
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/