Re: [PATCH net-next v2 2/6] net: phy: microchip_t1s: replace read-modify-write code with phy_modify_mmd

[Parthiban.Veerasooran]

Hi Andrew,

On 22/05/23 6:01 pm, Andrew Lunn wrote:
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> 
>>
>>        /* Read-Modified Write Pseudocode (from AN1699)
>>         * current_val = read_register(mmd, addr) // Read current register value
> 
> Hi Parthiban
> 
> Maybe extend the comment to indicate that although AN1699 says Read,
> Modify, Write, the write is not required if the register already has
> the required value. That is what phy_modify_mmd() actually does.
Sure, I will add it in the next version.

Best Regards,
Parthiban V
> 
>> @@ -74,12 +72,11 @@ static int lan867x_config_init(struct phy_device *phydev)
>>         * write_register(mmd, addr, new_val) // Write back updated register value
>>         */
>>        for (int i = 0; i < ARRAY_SIZE(lan867x_fixup_registers); i++) {
>> -             reg = lan867x_fixup_registers[i];
>> -             reg_value = phy_read_mmd(phydev, MDIO_MMD_VEND2, reg);
>> -             reg_value &= ~lan867x_fixup_masks[i];
>> -             reg_value |= lan867x_fixup_values[i];
>> -             err = phy_write_mmd(phydev, MDIO_MMD_VEND2, reg, reg_value);
>> -             if (err != 0)
>> +             err = phy_modify_mmd(phydev, MDIO_MMD_VEND2,
>> +                                  lan867x_fixup_registers[i],
>> +                                  lan867x_fixup_masks[i],
>> +                                  lan867x_fixup_values[i]);
>> +             if (err)
>>                        return err;
>>        }
> 
> 
>      Andrew
> 
> ---
> pw-bot: cr