Re: [PATCH v3 1/6] phy: add a driver for the Berlin SATA PHY

["Antoine Ténart" <antoine.tenart@free-electrons.com>]

Hi,

On Wed, May 14, 2014 at 03:43:03PM +0530, Kishon Vijay Abraham I wrote:
> Hi,
> 
> On Wednesday 14 May 2014 03:18 PM, Antoine Ténart wrote:

[…]

> > +#define to_berlin_sata_phy_priv(desc)	\
> > +	container_of((desc), struct phy_berlin_priv, phys[(desc)->index])
> > +
> > +struct phy_berlin_desc {
> > +	struct phy	*phy;
> > +	u32		val;
> > +	unsigned	index;
> > +};
> > +
> > +struct phy_berlin_priv {
> > +	void __iomem	*base;
> > +	spinlock_t	lock;
> > +	struct phy_berlin_desc	phys[BERLIN_SATA_PHY_NB];
> 
> Can't we do away with hardcoding BERLIN_SATA_PHY_NB?

We can't if we want to be able to use the container_of macro in
to_berlin_sata_phy_priv(). And we want a common structure to store the
common spinlock and base address.

[…]

> > +		/*
> > +		 * By default the PHY node is used to request and match a PHY.
> > +		 * We describe one PHY per sub-node here. Use the right node.
> > +		 */
> > +		phy->dev.of_node = child;
> > +
> > +		priv->phys[phy_id].phy = phy;
> > +		priv->phys[phy_id].val = desc[phy_id].val;
> > +		priv->phys[phy_id].index = phy_id;
> > +		phy_set_drvdata(phy, &priv->phys[phy_id]);
> > +
> > +		/* Make sure the PHY is off */
> > +		phy_berlin_sata_power_off(phy);
> > +
> > +		phy_provider = devm_of_phy_provider_register(&phy->dev,
> > +							     of_phy_simple_xlate);
> > +		if (IS_ERR(phy_provider))
> > +			return PTR_ERR(phy_provider);
> 
> was this intentional? registering multiple PHY providers?

Yes. Each sub-node describe a PHY and register as a PHY provider. This
allow to reference the PHY as <&sata_phy0> and not <&sata_phy 0>. It
would be confusing to have a sub-node sata_phy0 and to use its parent
to access it.

Antoine

-- 
Antoine Ténart, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com