RE: [PATCH net-next 2/3] lan78xx: setting phy features in phy driver

[Woojung.Huh]

I'll submit patch for review.

- Woojung

> On 10/02/2016 15:18, woojung@microchip.com wrote:
> >>> +static int lan88xx_config_init(struct phy_device *phydev)
> >>> +{
> >>> + phydev->supported &= phydev->drv->features;
> >>> + phydev->advertising &= phydev->drv->features;
> >>
> >> This looks suspicious, phy_probe() takes the driver supported features
> >> and assigns it to phydev->supported, and phydev->advertising, is not
> >> that working somehow?
> >>
> >> genphy_config_init() does look at the current MII_BMRS value to
> >> determine what is supported by the PHY, and masks it in
> >> phydev->supported, so that could indeed be an issue if we had not had a
> >> change to mask with the supported modes before.
> >>
> >> I think we need more explanation here as to what kind of bug you may
> >> have been observing, there could be one.
> >
> > SUPPORTED_Pause & SUPPORTED_Asym_Pause set at phydev->features
> are removed by genphy_config_init().
> > As you pointed, it may be better to modify genphy_config_init() than each
> driver's config_init routine.
> 
> I see, that is definitively a bug, we should not clear these bits if the
> Ethernet MAC driver asked for them.
> --
> Florian

Re: [PATCH net-next 2/3] lan78xx: setting phy features in phy driver

[Florian Fainelli]

On 10/02/16 13:13, woojung@microchip.com wrote:
> 
> Update to set default phy supported & advertising features from phy device
> structure and remove unnecessary code in the nic driver.
> 
> Signed-off-by: Woojung Huh 
> ---
>  drivers/net/phy/microchip.c | 10 +-
>  drivers/net/usb/lan78xx.c   |  7 +--
>  2 files changed, 10 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/net/phy/microchip.c b/drivers/net/phy/microchip.c
> index 15f8206..7a457a4 100644
> --- a/drivers/net/phy/microchip.c
> +++ b/drivers/net/phy/microchip.c
> @@ -106,6 +106,14 @@ static int lan88xx_set_wol(struct phy_device *phydev,
>   return 0;
>  }
>  
> +static int lan88xx_config_init(struct phy_device *phydev)
> +{
> + phydev->supported &= phydev->drv->features;
> + phydev->advertising &= phydev->drv->features;

This looks suspicious, phy_probe() takes the driver supported features
and assigns it to phydev->supported, and phydev->advertising, is not
that working somehow?

genphy_config_init() does look at the current MII_BMRS value to
determine what is supported by the PHY, and masks it in
phydev->supported, so that could indeed be an issue if we had not had a
change to mask with the supported modes before.

I think we need more explanation here as to what kind of bug you may
have been observing, there could be one.

> +
> + return 0;
> +}
> +
>  static struct phy_driver microchip_phy_driver[] = {
>  {
>   .phy_id = 0x0007c130,
> @@ -119,7 +127,7 @@ static struct phy_driver microchip_phy_driver[] = {
>   .probe  = lan88xx_probe,
>   .remove = lan88xx_remove,
>  
> - .config_init= genphy_config_init,
> + .config_init= lan88xx_config_init,
>   .config_aneg= genphy_config_aneg,
>   .read_status= genphy_read_status,
>  
> diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c
> index b14b22d..1fd8072 100644
> --- a/drivers/net/usb/lan78xx.c
> +++ b/drivers/net/usb/lan78xx.c
> @@ -1623,12 +1623,7 @@ static int lan78xx_phy_init(struct lan78xx_net *dev)
>  
>   /* MAC doesn't support 1000T Half */
>   phydev->supported &= ~SUPPORTED_1000baseT_Half;
> - phydev->supported |= (SUPPORTED_10baseT_Half |
> -   SUPPORTED_10baseT_Full |
> -   SUPPORTED_100baseT_Half |
> -   SUPPORTED_100baseT_Full |
> -   SUPPORTED_1000baseT_Full |
> -   SUPPORTED_Pause | SUPPORTED_Asym_Pause);



> +
>   genphy_config_aneg(phydev);
>  
>   phy_start(phydev);
> 


-- 
Florian

Re: [PATCH net-next 2/3] lan78xx: setting phy features in phy driver

[Florian Fainelli]

On 10/02/2016 15:18, woojung@microchip.com wrote:
>>> +static int lan88xx_config_init(struct phy_device *phydev)
>>> +{
>>> +   phydev->supported &= phydev->drv->features;
>>> +   phydev->advertising &= phydev->drv->features;
>>
>> This looks suspicious, phy_probe() takes the driver supported features
>> and assigns it to phydev->supported, and phydev->advertising, is not
>> that working somehow?
>>
>> genphy_config_init() does look at the current MII_BMRS value to
>> determine what is supported by the PHY, and masks it in
>> phydev->supported, so that could indeed be an issue if we had not had a
>> change to mask with the supported modes before.
>>
>> I think we need more explanation here as to what kind of bug you may
>> have been observing, there could be one.
> 
> SUPPORTED_Pause & SUPPORTED_Asym_Pause set at phydev->features  are removed 
> by genphy_config_init().
> As you pointed, it may be better to modify genphy_config_init() than each 
> driver's config_init routine.

I see, that is definitively a bug, we should not clear these bits if the
Ethernet MAC driver asked for them.
--
Florian

RE: [PATCH net-next 2/3] lan78xx: setting phy features in phy driver

[Woojung.Huh]

> > +static int lan88xx_config_init(struct phy_device *phydev)
> > +{
> > +   phydev->supported &= phydev->drv->features;
> > +   phydev->advertising &= phydev->drv->features;
> 
> This looks suspicious, phy_probe() takes the driver supported features
> and assigns it to phydev->supported, and phydev->advertising, is not
> that working somehow?
> 
> genphy_config_init() does look at the current MII_BMRS value to
> determine what is supported by the PHY, and masks it in
> phydev->supported, so that could indeed be an issue if we had not had a
> change to mask with the supported modes before.
> 
> I think we need more explanation here as to what kind of bug you may
> have been observing, there could be one.

SUPPORTED_Pause & SUPPORTED_Asym_Pause set at phydev->features  are removed by 
genphy_config_init().
As you pointed, it may be better to modify genphy_config_init() than each 
driver's config_init routine.

- Woojung