diff mbox series

[net-next,1/1] net: phy: fix invalid phy id when probe using C22

Message ID 20210316085748.3017-1-vee.khee.wong@intel.com
State Superseded
Headers show
Series [net-next,1/1] net: phy: fix invalid phy id when probe using C22 | expand

Commit Message

Wong, Vee Khee March 16, 2021, 8:57 a.m. UTC
When using Clause-22 to probe for PHY devices such as the Marvell
88E2110, PHY ID with value 0 is read from the MII PHYID registers
which caused the PHY framework failed to attach the Marvell PHY
driver.

Fixed this by adding a check of PHY ID equals to all zeroes.

Cc: stable@vger.kernel.org
Reviewed-by: Voon Weifeng <voon.weifeng@intel.com>
Signed-off-by: Wong Vee Khee <vee.khee.wong@intel.com>
---
 drivers/net/phy/phy_device.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Heiner Kallweit March 17, 2021, 8:15 a.m. UTC | #1
On 16.03.2021 09:57, Wong Vee Khee wrote:
> When using Clause-22 to probe for PHY devices such as the Marvell

> 88E2110, PHY ID with value 0 is read from the MII PHYID registers

> which caused the PHY framework failed to attach the Marvell PHY

> driver.

> 


The issue occurs with a MAC driver that sets MDIO bus capability
flag MDIOBUS_C22_C45, like stmmac? Or what is the affected MAC
driver?

And if you state it's a fix, a Fixes tag would be needed.

> Fixed this by adding a check of PHY ID equals to all zeroes.

> 

> Cc: stable@vger.kernel.org

> Reviewed-by: Voon Weifeng <voon.weifeng@intel.com>

> Signed-off-by: Wong Vee Khee <vee.khee.wong@intel.com>

> ---

>  drivers/net/phy/phy_device.c | 4 ++--

>  1 file changed, 2 insertions(+), 2 deletions(-)

> 

> diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c

> index a009d1769b08..f1afc00fcba2 100644

> --- a/drivers/net/phy/phy_device.c

> +++ b/drivers/net/phy/phy_device.c

> @@ -820,8 +820,8 @@ static int get_phy_c22_id(struct mii_bus *bus, int addr, u32 *phy_id)

>  

>  	*phy_id |= phy_reg;

>  

> -	/* If the phy_id is mostly Fs, there is no device there */

> -	if ((*phy_id & 0x1fffffff) == 0x1fffffff)

> +	/* If the phy_id is mostly Fs or all zeroes, there is no device there */

> +	if (((*phy_id & 0x1fffffff) == 0x1fffffff) || (*phy_id == 0))

>  		return -ENODEV;

>  

>  	return 0;

>
Wong, Vee Khee March 18, 2021, 6:54 a.m. UTC | #2
> -----Original Message-----

> From: Heiner Kallweit <hkallweit1@gmail.com>

> Sent: Wednesday, March 17, 2021 4:15 PM

> To: Wong, Vee Khee <vee.khee.wong@intel.com>; Andrew Lunn

> <andrew@lunn.ch>; Russell King <linux@armlinux.org.uk>; David S . Miller

> <davem@davemloft.net>; Jakub Kicinski <kuba@kernel.org>

> Cc: netdev@vger.kernel.org; linux-kernel@vger.kernel.org;

> stable@vger.kernel.org; Voon Weifeng <voon.weifeng@intel.com>; Ong,

> Boon Leong <boon.leong.ong@intel.com>

> Subject: Re: [PATCH net-next 1/1] net: phy: fix invalid phy id when probe

> using C22

> 

> On 16.03.2021 09:57, Wong Vee Khee wrote:

> > When using Clause-22 to probe for PHY devices such as the Marvell

> > 88E2110, PHY ID with value 0 is read from the MII PHYID registers

> > which caused the PHY framework failed to attach the Marvell PHY

> > driver.

> >

> 

> The issue occurs with a MAC driver that sets MDIO bus capability

> flag MDIOBUS_C22_C45, like stmmac? Or what is the affected MAC

> driver?

> 


Yes, you are right. This issue is seen when MarvellE2110 is used with
the STMMAC.

> And if you state it's a fix, a Fixes tag would be needed.

> 


Noted. Will send a v2 and marked for net.

> > Fixed this by adding a check of PHY ID equals to all zeroes.

> >

> > Cc: stable@vger.kernel.org

> > Reviewed-by: Voon Weifeng <voon.weifeng@intel.com>

> > Signed-off-by: Wong Vee Khee <vee.khee.wong@intel.com>

> > ---

> >  drivers/net/phy/phy_device.c | 4 ++--

> >  1 file changed, 2 insertions(+), 2 deletions(-)

> >

> > diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c

> > index a009d1769b08..f1afc00fcba2 100644

> > --- a/drivers/net/phy/phy_device.c

> > +++ b/drivers/net/phy/phy_device.c

> > @@ -820,8 +820,8 @@ static int get_phy_c22_id(struct mii_bus *bus, int

> addr, u32 *phy_id)

> >

> >  	*phy_id |= phy_reg;

> >

> > -	/* If the phy_id is mostly Fs, there is no device there */

> > -	if ((*phy_id & 0x1fffffff) == 0x1fffffff)

> > +	/* If the phy_id is mostly Fs or all zeroes, there is no device there */

> > +	if (((*phy_id & 0x1fffffff) == 0x1fffffff) || (*phy_id == 0))

> >  		return -ENODEV;

> >

> >  	return 0;

> >
diff mbox series

Patch

diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index a009d1769b08..f1afc00fcba2 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -820,8 +820,8 @@  static int get_phy_c22_id(struct mii_bus *bus, int addr, u32 *phy_id)
 
 	*phy_id |= phy_reg;
 
-	/* If the phy_id is mostly Fs, there is no device there */
-	if ((*phy_id & 0x1fffffff) == 0x1fffffff)
+	/* If the phy_id is mostly Fs or all zeroes, there is no device there */
+	if (((*phy_id & 0x1fffffff) == 0x1fffffff) || (*phy_id == 0))
 		return -ENODEV;
 
 	return 0;