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>
...
quoted hunk ↗ jump to hunk
+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.
quoted hunk ↗ jump to hunk
+
+ 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");