Re: [PATCH v4 13/14] net: phy: adin: add ethtool get_stats support

From: Andrew Lunn
Date: Mon Aug 12 2019 - 10:33:21 EST


> +static int adin_read_mmd_stat_regs(struct phy_device *phydev,
> + struct adin_hw_stat *stat,
> + u32 *val)
> +{
> + int ret;
> +
> + ret = phy_read_mmd(phydev, MDIO_MMD_VEND1, stat->reg1);
> + if (ret < 0)
> + return ret;
> +
> + *val = (ret & 0xffff);
> +
> + if (stat->reg2 == 0)
> + return 0;
> +
> + ret = phy_read_mmd(phydev, MDIO_MMD_VEND1, stat->reg2);
> + if (ret < 0)
> + return ret;
> +
> + *val <<= 16;
> + *val |= (ret & 0xffff);
> +
> + return 0;
> +}

It still looks like you have not dealt with overflow from the LSB into
the MSB between the two reads.

do {
hi1 = phy_read_mmd(phydev, MDIO_MMD_VEND1, stat->reg2);
if (hi1 < 0)
return hi1;

low = phy_read_mmd(phydev, MDIO_MMD_VEND1, stat->reg1);
if (low < 0)
return low;

hi2 = phy_read_mmd(phydev, MDIO_MMD_VEND1, stat->reg2);
if (hi2 < 0)
return hi1;
} while (hi1 != hi2)

return low | (hi << 16);

Andrew