Re: [net-next PATCH v1 3/7] net: phy: Introduce fwnode_get_phy_id()

[Russell King - ARM Linux admin]

On Fri, Oct 02, 2020 at 08:14:07AM -0700, Florian Fainelli wrote:
> On 10/2/2020 4:05 AM, Grant Likely wrote:
> > On 30/09/2020 17:04, Calvin Johnson wrote:
> > > Extract phy_id from compatible string. This will be used by
> > > fwnode_mdiobus_register_phy() to create phy device using the
> > > phy_id.
> > > 
> > > Signed-off-by: Calvin Johnson <calvin.johnson@xxxxxxxxxxx>
> > > ---
> > > 
> > >   drivers/net/phy/phy_device.c | 32 +++++++++++++++++++++++++++++++-
> > >   include/linux/phy.h          |  5 +++++
> > >   2 files changed, 36 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
> > > index c4aec56d0a95..162abde6223d 100644
> > > --- a/drivers/net/phy/phy_device.c
> > > +++ b/drivers/net/phy/phy_device.c
> > > @@ -9,6 +9,7 @@
> > >   #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> > > +#include <linux/acpi.h>
> > >   #include <linux/bitmap.h>
> > >   #include <linux/delay.h>
> > >   #include <linux/errno.h>
> > > @@ -845,6 +846,27 @@ static int get_phy_c22_id(struct mii_bus *bus,
> > > int addr, u32 *phy_id)
> > >       return 0;
> > >   }
> > > +/* Extract the phy ID from the compatible string of the form
> > > + * ethernet-phy-idAAAA.BBBB.
> > > + */
> > > +int fwnode_get_phy_id(struct fwnode_handle *fwnode, u32 *phy_id)
> > > +{
> > > +    unsigned int upper, lower;
> > > +    const char *cp;
> > > +    int ret;
> > > +
> > > +    ret = fwnode_property_read_string(fwnode, "compatible", &cp);
> > > +    if (ret)
> > > +        return ret;
> > > +
> > > +    if (sscanf(cp, "ethernet-phy-id%4x.%4x", &upper, &lower) == 2) {
> > > +        *phy_id = ((upper & 0xFFFF) << 16) | (lower & 0xFFFF);
> > > +        return 0;
> > > +    }
> > > +    return -EINVAL;
> > > +}
> > > +EXPORT_SYMBOL(fwnode_get_phy_id);
> > 
> > This block, and the changes in patch 4 duplicate functions from
> > drivers/of/of_mdio.c, but it doesn't refactor anything in
> > drivers/of/of_mdio.c to use the new path. Is your intent to bring all of
> > the parsing in these functions of "compatible" into the ACPI code path?
> > 
> > If so, then the existing code path needs to be refactored to work with
> > fwnode_handle instead of device_node.
> > 
> > If not, then the DT path in these functions should call out to of_mdio,
> > while the ACPI path only does what is necessary.
> 
> Rob has been asking before to have drivers/of/of_mdio.c be merged or at
> least relocated within drivers/net/phy where it would naturally belong. As a
> preliminary step towards ACPI support that would seem reasonable to do.

I think even I have commented on specific functions while reviewing
patches from NXP that the DT/ACPI code should use common bases...

I have been planning that if that doesn't get done, then I'd do it,
but really NXP should do it being the ones adding this infrastructure;
they should do the job properly and not take advantage of volunteers
in the community cleaning up their resulting submissions.

-- 
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