2022-03-13 10:50:38

by Andrew Lunn

Subject: Re: [PATCH net-next 2/3] net: mdio: mscc-miim: replace magic numbers for the bus reset

> diff --git a/drivers/net/mdio/mdio-mscc-miim.c b/drivers/net/mdio/mdio-mscc-miim.c
> index 64fb76c1e395..7773d5019e66 100644
> --- a/drivers/net/mdio/mdio-mscc-miim.c
> +++ b/drivers/net/mdio/mdio-mscc-miim.c
> @@ -158,18 +158,18 @@ static int mscc_miim_reset(struct mii_bus *bus)
> {
> struct mscc_miim_dev *miim = bus->priv;
> int offset = miim->phy_reset_offset;
> + int mask = PHY_CFG_PHY_ENA | PHY_CFG_PHY_COMMON_RESET |
> + PHY_CFG_PHY_RESET;

> - ret = regmap_write(miim->phy_regs,
> - MSCC_PHY_REG_PHY_CFG + offset, 0x1ff);
> + ret = regmap_write(miim->phy_regs, offset, mask);

Is mask the correct name? It is not being used in the typical way for
a mask.

Andrew

2022-03-13 11:00:56

by Michael Walle

Subject: Re: [PATCH net-next 2/3] net: mdio: mscc-miim: replace magic numbers for the bus reset

Am 2022-03-13 01:51, schrieb Andrew Lunn:
>> diff --git a/drivers/net/mdio/mdio-mscc-miim.c
>> b/drivers/net/mdio/mdio-mscc-miim.c
>> index 64fb76c1e395..7773d5019e66 100644
>> --- a/drivers/net/mdio/mdio-mscc-miim.c
>> +++ b/drivers/net/mdio/mdio-mscc-miim.c
>> @@ -158,18 +158,18 @@ static int mscc_miim_reset(struct mii_bus *bus)
>> {
>> struct mscc_miim_dev *miim = bus->priv;
>> int offset = miim->phy_reset_offset;
>> + int mask = PHY_CFG_PHY_ENA | PHY_CFG_PHY_COMMON_RESET |
>> + PHY_CFG_PHY_RESET;
>
>> - ret = regmap_write(miim->phy_regs,
>> - MSCC_PHY_REG_PHY_CFG + offset, 0x1ff);
>> + ret = regmap_write(miim->phy_regs, offset, mask);
>
> Is mask the correct name? It is not being used in the typical way for
> a mask.

It is the mask of all the reset bits, see also patch 3/3. Either all
these bits are set or none. Do you have any suggestion? I thought about
adding mask and value for the remap_update_bits() in patch 3/3 but
decided against it, just because it doesn't add any value because
mask and value are the same.

-michael

2022-03-14 07:54:14

by Andrew Lunn

Subject: Re: [PATCH net-next 2/3] net: mdio: mscc-miim: replace magic numbers for the bus reset

On Sun, Mar 13, 2022 at 02:17:55AM +0100, Michael Walle wrote:
> Am 2022-03-13 01:51, schrieb Andrew Lunn:
> > > diff --git a/drivers/net/mdio/mdio-mscc-miim.c
> > > b/drivers/net/mdio/mdio-mscc-miim.c
> > > index 64fb76c1e395..7773d5019e66 100644
> > > --- a/drivers/net/mdio/mdio-mscc-miim.c
> > > +++ b/drivers/net/mdio/mdio-mscc-miim.c
> > > @@ -158,18 +158,18 @@ static int mscc_miim_reset(struct mii_bus *bus)
> > > {
> > > struct mscc_miim_dev *miim = bus->priv;
> > > int offset = miim->phy_reset_offset;
> > > + int mask = PHY_CFG_PHY_ENA | PHY_CFG_PHY_COMMON_RESET |
> > > + PHY_CFG_PHY_RESET;
> >
> > > - ret = regmap_write(miim->phy_regs,
> > > - MSCC_PHY_REG_PHY_CFG + offset, 0x1ff);
> > > + ret = regmap_write(miim->phy_regs, offset, mask);
> >
> > Is mask the correct name? It is not being used in the typical way for
> > a mask.
>
> It is the mask of all the reset bits, see also patch 3/3. Either all
> these bits are set or none.

Yes, it is you just don't use it in the typical way for a mask

foo = bar & mask;

The name mask made me look for a read-modify-write or similar. And
that then makes me thing of race conditions.

> Do you haave any suggestion?

value everywhere? Or phy_reset_bits?

Andrew