Messages in this thread | | | Date | Thu, 25 May 2023 13:02:39 +0200 | From | Simon Horman <> | Subject | Re: [PATCH net-next v2 1/4] net: mdio: Introduce a regmap-based mdio driver |
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On Thu, May 25, 2023 at 12:11:23PM +0200, Maxime Chevallier wrote: > There exists several examples today of devices that embed an ethernet > PHY or PCS directly inside an SoC. In this situation, either the device > is controlled through a vendor-specific register set, or sometimes > exposes the standard 802.3 registers that are typically accessed over > MDIO. > > As phylib and phylink are designed to use mdiodevices, this driver > allows creating a virtual MDIO bus, that translates mdiodev register > accesses to regmap accesses. > > The reason we use regmap is because there are at least 3 such devices > known today, 2 of them are Altera TSE PCS's, memory-mapped, exposed > with a 4-byte stride in stmmac's dwmac-socfpga variant, and a 2-byte > stride in altera-tse. The other one (nxp,sja1110-base-tx-mdio) is > exposed over SPI. > > Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
...
> +struct mii_bus *devm_mdio_regmap_register(struct device *dev, > + const struct mdio_regmap_config *config) > +{ > + struct mdio_regmap_config *mrc; > + struct mii_bus *mii; > + int rc; > + > + if (!config->parent) > + return ERR_PTR(-EINVAL); > + > + mii = devm_mdiobus_alloc_size(config->parent, sizeof(*mrc)); > + if (!mii) > + return ERR_PTR(-ENOMEM); > + > + mrc = mii->priv; > + memcpy(mrc, config, sizeof(*mrc)); > + > + mrc->regmap = config->regmap; > + mrc->valid_addr = config->valid_addr; > + > + mii->name = DRV_NAME; > + strscpy(mii->id, config->name, MII_BUS_ID_SIZE); > + mii->parent = config->parent; > + mii->read = mdio_regmap_read_c22; > + mii->write = mdio_regmap_write_c22; > + > + if (config->autoscan) > + mii->phy_mask = ~BIT(config->valid_addr); > + else > + mii->phy_mask = ~0UL;
Hi Maxime,
phy_mask is a u32. But 0UL may be either 32 or 64 bits wide.
I think a better approach would be to use U32_MAX.
> + > + rc = devm_mdiobus_register(dev, mii); > + if (rc) { > + dev_err(config->parent, "Cannot register MDIO bus![%s] (%d)\n", mii->id, rc); > + return ERR_PTR(rc); > + } > + > + return mii; > +} > +EXPORT_SYMBOL_GPL(devm_mdio_regmap_register); > + > +MODULE_DESCRIPTION("MDIO API over regmap"); > +MODULE_AUTHOR("Maxime Chevallier <maxime.chevallier@bootlin.com>"); > +MODULE_LICENSE("GPL");
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