From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Rutland Subject: Re: [RFC PATCH 1/3] of: provide a binding for the 'fixed-link' property Date: Tue, 23 Jul 2013 12:22:59 +0100 Message-ID: <20130723112259.GE4833@e106331-lin.cambridge.arm.com> References: <1373902450-11857-1-git-send-email-thomas.petazzoni@free-electrons.com> <1373902450-11857-2-git-send-email-thomas.petazzoni@free-electrons.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1373902450-11857-2-git-send-email-thomas.petazzoni@free-electrons.com> Content-Language: en-US Sender: netdev-owner@vger.kernel.org To: Thomas Petazzoni Cc: Grant Likely , "rob.herring@calxeda.com" , "David S. Miller" , Florian Fainelli , "linux-arm-kernel@lists.infradead.org" , "netdev@vger.kernel.org" , "devicetree-discuss@lists.ozlabs.org" , Lior Amsalem , Gregory Clement , Ezequiel Garcia List-Id: devicetree@vger.kernel.org Hi Thomas, On Mon, Jul 15, 2013 at 04:34:08PM +0100, Thomas Petazzoni wrote: > Some Ethernet MACs have a "fixed link", and are not connected to a > normal MDIO-managed PHY device. For those situations, a Device Tree > binding allows to describe a "fixed link", as a "fixed-link" property > of the Ethernet device Device Tree node. > > This patch adds: > > * A documentation for the Device Tree property "fixed-link". > > * A of_phy_register_fixed_link() OF helper, which provided an OF node > that contains a "fixed-link" property, registers the corresponding > fixed PHY. > > * Removes the warning on the of_phy_connect_fixed_link() that says > new drivers should not use it, since Grant Likely indicated that > this "fixed-link" property is indeed the way to go. > > Signed-off-by: Thomas Petazzoni > --- > .../devicetree/bindings/net/fixed-link.txt | 26 ++++++++++++++++ > drivers/of/of_mdio.c | 36 +++++++++++++++++++--- > include/linux/of_mdio.h | 10 ++++++ > 3 files changed, 68 insertions(+), 4 deletions(-) > create mode 100644 Documentation/devicetree/bindings/net/fixed-link.txt > > diff --git a/Documentation/devicetree/bindings/net/fixed-link.txt b/Documentation/devicetree/bindings/net/fixed-link.txt > new file mode 100644 > index 0000000..25a009a > --- /dev/null > +++ b/Documentation/devicetree/bindings/net/fixed-link.txt > @@ -0,0 +1,26 @@ > +Fixed link Device Tree binding > +------------------------------ > + > +Some Ethernet MACs have a "fixed link", and are not connected to a > +normal MDIO-managed PHY device. For those situations, a Device Tree > +binding allows to describe a "fixed link". Are partictular MACs fixed link, or can some either be either fixed link or wired to an MDIO-managed PHY? i.e. can we assume a given MAC is fixed-link from its compatible string? > + > +Such a fixed link situation is described within an Ethernet device > +Device Tree node using a 'fixed-link' property, composed of 5 > +elements: I'm not sure grouping these values together is the best way of handling this. It's rather opaque, and inflexible for future extension. > + > + 1. A fake PHY ID, which must be unique accross all fixed-link PHYs in > + the system. Is there any reason this couldn't be allocated dynamically within the kernel as needed? I don't see why an arbitrary unique value should be a dt binding requirement; it seems like a leak of Linux implementation details. > + 2. The duplex (1 for full-duplex, 0 for half-duplex) Will this change for a given MAC? Could we not have a boolean property for each of these, and require one to be present? Possibly fixed-link-full-duplex / fix-link-half-duplex? > + 3. The speed (10, 100, 1000) fixed-link-speed? > + 4. The pause setting (1 for enabled, 0 for disabled) > + 5. The asym pause setting (1 for enabled, 0 for disabled) Boolean properties for both of these? Thanks, Mark. > + > +Example: > + > +ethernet@0 { > + ... > + fixed-link = <1 1 1000 0 0>; > + ... > +}; > + > diff --git a/drivers/of/of_mdio.c b/drivers/of/of_mdio.c > index d5a57a9..66d5591 100644 > --- a/drivers/of/of_mdio.c > +++ b/drivers/of/of_mdio.c > @@ -14,6 +14,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -215,10 +216,6 @@ EXPORT_SYMBOL(of_phy_connect); > * @dev: pointer to net_device claiming the phy > * @hndlr: Link state callback for the network device > * @iface: PHY data interface type > - * > - * This function is a temporary stop-gap and will be removed soon. It is > - * only to support the fs_enet, ucc_geth and gianfar Ethernet drivers. Do > - * not call this function from new drivers. > */ > struct phy_device *of_phy_connect_fixed_link(struct net_device *dev, > void (*hndlr)(struct net_device *), > @@ -247,3 +244,34 @@ struct phy_device *of_phy_connect_fixed_link(struct net_device *dev, > return IS_ERR(phy) ? NULL : phy; > } > EXPORT_SYMBOL(of_phy_connect_fixed_link); > + > +#if defined(CONFIG_FIXED_PHY) > +/** > + * of_phy_register_fixed_link - Parse fixed-link property and register a dummy phy > + * @np: pointer to the OF device node that contains the "fixed-link" > + * property for which a dummy phy should be registered. > + */ > +#define FIXED_LINK_PROPERTIES_COUNT 5 > +int of_phy_register_fixed_link(struct device_node *np) > +{ > + struct fixed_phy_status status = {}; > + u32 fixed_link_props[FIXED_LINK_PROPERTIES_COUNT]; > + int ret; > + > + ret = of_property_read_u32_array(np, "fixed-link", > + fixed_link_props, > + FIXED_LINK_PROPERTIES_COUNT); > + if (ret < 0) > + return ret; > + > + status.link = 1; > + status.duplex = fixed_link_props[1]; > + status.speed = fixed_link_props[2]; > + status.pause = fixed_link_props[3]; > + status.asym_pause = fixed_link_props[4]; > + > + return fixed_phy_add(PHY_POLL, fixed_link_props[0], > + &status); > +} > +EXPORT_SYMBOL(of_phy_register_fixed_link); > +#endif > diff --git a/include/linux/of_mdio.h b/include/linux/of_mdio.h > index 8163107..bf6efea 100644 > --- a/include/linux/of_mdio.h > +++ b/include/linux/of_mdio.h > @@ -57,4 +57,14 @@ static inline struct mii_bus *of_mdio_find_bus(struct device_node *mdio_np) > } > #endif /* CONFIG_OF */ > > +#if defined(CONFIG_OF) && defined(CONFIG_FIXED_PHY) > +extern int of_phy_register_fixed_link(struct device_node *np); > +#else > +static inline int of_phy_register_fixed_link(struct device_node *np) > +{ > + return -ENOSYS; > +} > +#endif > + > + > #endif /* __LINUX_OF_MDIO_H */ > -- > 1.8.1.2 > > -- > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >