Re: [PATCH] of_mdio: fix phy interrupt passing

[Sergei Shtylyov]

Hello.

On 02/18/2014 08:02 PM, Grant Likely wrote:

> > > On Mon, 17 Feb 2014 16:29:40 +0000, Ben Dooks <ben.dooks@xxxxxxxxxxxxxxx> wrote:
> > > > The of_mdiobus_register_phy() is not setting phy->irq this causing
> > > > some drivers to incorrectly assume that the PHY does not have an
> > > > IRQ associated with it or install an interrupt handler for the
> > > > PHY.

> > > > Simplify the code setting irq and set the phy->irq at the same
> > > > time so that the case if mdio->irq is not NULL is easier to read.

> > > > This fixes the issue:
> > > >    net eth0: attached PHY 1 (IRQ -1) to driver Micrel KSZ8041RNLI

> > > > to the correct:
> > > >    net eth0: attached PHY 1 (IRQ 416) to driver Micrel KSZ8041RNLI

> > > > Signed-off-by: Ben Dooks <ben.dooks@xxxxxxxxxxxxxxx>
> > > > ---
> > > >    drivers/of/of_mdio.c | 12 ++++++------
> > > >    1 file changed, 6 insertions(+), 6 deletions(-)

> > > > diff --git a/drivers/of/of_mdio.c b/drivers/of/of_mdio.c
> > > > index 875b7b6..7b3e7b0 100644
> > > > --- a/drivers/of/of_mdio.c
> > > > +++ b/drivers/of/of_mdio.c
> > > > @@ -44,7 +44,7 @@ static int of_mdiobus_register_phy(struct mii_bus *mdio, struct device_node *chi
> > > >    {
> > > >    	struct phy_device *phy;
> > > >    	bool is_c45;
> > > > -	int rc, prev_irq;
> > > > +	int rc;
> > > >    	u32 max_speed = 0;
> > > >
> > > >    	is_c45 = of_device_is_compatible(child,
> > > > @@ -55,11 +55,11 @@ static int of_mdiobus_register_phy(struct mii_bus *mdio, struct device_node *chi
> > > >    		return 1;
> > > >
> > > >    	if (mdio->irq) {
> > > > -		prev_irq = mdio->irq[addr];
> > > > -		mdio->irq[addr] =
> > > > -			irq_of_parse_and_map(child, 0);
> > > > -		if (!mdio->irq[addr])
> > > > -			mdio->irq[addr] = prev_irq;

> > > I cannot for the life for me remeber why the code was structured that
> > > way. Your change is better.

> > > > +		rc = irq_of_parse_and_map(child, 0);
> > > > +		if (rc > 0) {
> > > > +			mdio->irq[addr] = rc;
> > > > +			phy->irq = rc;
> > > > +		}
> > > >    	}

> > > The outer if is merely protecting against no irq array being allocated
> > > for the bus. Would not the following be better:

> > > 	rc = irq_of_parse_and_map(child, 0);
> > > 	if (rc > 0) {
> > > 		phy->irq = rc;
> > > 		if (mdio->irq)
> > > 			mdio->irq[addr] = rc;
> > > 	}

> > Thanks, that makes sense, although we've both failed to work
> > out if mdio->irq is set, and rc <= 0 case, so:

> >    	rc = irq_of_parse_and_map(child, 0);
> >    	if (rc > 0) {
> >    		phy->irq = rc;
> >    		if (mdio->irq)
> >    			mdio->irq[addr] = rc;
> >    	} else {
> > 		if (mdio->irq)
> > 			phy->irq = mdio->irq[addr];
> > 	}

> Is this actually a valid thing to do? I think the only time mdio->irq[]
> is non-zero is when it is set to PHY_POLL. Is it valid to set phy->irq
> to PHY_POLL? I didn't think it was.

   It is valid, AFAIK.

> g.

> > --
> > Ben Dooks				http://www.codethink.co.uk/
> > Senior Engineer				Codethink - Providing Genius

WBR, Sergei

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