Re: [PATCH v5 08/12] net: stmmac: starfive_dmac: Add phy interface settings

From: Andrew Lunn
Date: Fri Mar 03 2023 - 08:37:23 EST


> +static int starfive_dwmac_set_mode(struct plat_stmmacenet_data *plat_dat)
> +{
> + struct starfive_dwmac *dwmac = plat_dat->bsp_priv;
> + struct of_phandle_args args;
> + struct regmap *regmap;
> + unsigned int reg, mask, mode;
> + int err;
> +
> + switch (plat_dat->interface) {
> + case PHY_INTERFACE_MODE_RMII:
> + mode = MACPHYC_PHY_INFT_RMII;
> + break;
> +
> + case PHY_INTERFACE_MODE_RGMII:
> + case PHY_INTERFACE_MODE_RGMII_ID:
> + mode = MACPHYC_PHY_INFT_RGMII;
> + break;
> +
> + default:
> + dev_err(dwmac->dev, "Unsupported interface %d\n",
> + plat_dat->interface);
> + }

Please add a return -EINVAL;

> +
> + err = of_parse_phandle_with_fixed_args(dwmac->dev->of_node,
> + "starfive,syscon", 2, 0, &args);
> + if (err) {
> + dev_dbg(dwmac->dev, "syscon reg not found\n");
> + return -EINVAL;
> + }
> +
> + reg = args.args[0];
> + mask = args.args[1];
> + regmap = syscon_node_to_regmap(args.np);
> + of_node_put(args.np);
> + if (IS_ERR(regmap))
> + return PTR_ERR(regmap);
> +
> + return regmap_update_bits(regmap, reg, mask, mode << __ffs(mask));

This is a poor device tree binding. We generally don't allow bindings
which say put value X in register Y.

Could you add a table: interface mode, reg, mask? You can then do a
simple lookup based on the interface mode? No device tree binding
needed at all?

Andrew