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

[Florian Fainelli]

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.

Then, as Grant suggests you can start re-factoring as much as possible 
with using fwnode_handle.
--
Florian