This patch adds a PHY Abstraction Layer to the Linux Kernel, enabling

ethernet drivers to remain as ignorant as is reasonable of the connected
PHY's design and operation details.

Signed-off-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>

1 files changed, 378 insertions, 0 deletions

diff --git a/include/linux/phy.h b/include/linux/phy.h
new file mode 100644
index 0000000..3404804
--- /dev/null
+++ b/include/linux/phy.h
@@ -0,0 +1,378 @@
+/*
+ * include/linux/phy.h
+ *
+ * Framework and drivers for configuring and reading different PHYs
+ * Based on code in sungem_phy.c and gianfar_phy.c
+ *
+ * Author: Andy Fleming
+ *
+ * Copyright (c) 2004 Freescale Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ *
+ */
+
+#ifndef __PHY_H
+#define __PHY_H
+
+#include <linux/spinlock.h>
+#include <linux/device.h>
+
+#define PHY_BASIC_FEATURES	(SUPPORTED_10baseT_Half | \
+				 SUPPORTED_10baseT_Full | \
+				 SUPPORTED_100baseT_Half | \
+				 SUPPORTED_100baseT_Full | \
+				 SUPPORTED_Autoneg | \
+				 SUPPORTED_TP | \
+				 SUPPORTED_MII)
+
+#define PHY_GBIT_FEATURES	(PHY_BASIC_FEATURES | \
+				 SUPPORTED_1000baseT_Half | \
+				 SUPPORTED_1000baseT_Full)
+
+/* Set phydev->irq to PHY_POLL if interrupts are not supported,
+ * or not desired for this PHY.  Set to PHY_IGNORE_INTERRUPT if
+ * the attached driver handles the interrupt
+ */
+#define PHY_POLL		-1
+#define PHY_IGNORE_INTERRUPT	-2
+
+#define PHY_HAS_INTERRUPT	0x00000001
+#define PHY_HAS_MAGICANEG	0x00000002
+
+#define MII_BUS_MAX 4
+
+
+#define PHY_INIT_TIMEOUT 100000
+#define PHY_STATE_TIME		1
+#define PHY_FORCE_TIMEOUT	10
+#define PHY_AN_TIMEOUT		10
+
+#define PHY_MAX_ADDR 32
+
+/* The Bus class for PHYs.  Devices which provide access to
+ * PHYs should register using this structure */
+struct mii_bus {
+	const char *name;
+	int id;
+	void *priv;
+	int (*read)(struct mii_bus *bus, int phy_id, int regnum);
+	int (*write)(struct mii_bus *bus, int phy_id, int regnum, u16 val);
+	int (*reset)(struct mii_bus *bus);
+
+	/* A lock to ensure that only one thing can read/write
+	 * the MDIO bus at a time */
+	spinlock_t mdio_lock;
+
+	struct device *dev;
+
+	/* list of all PHYs on bus */
+	struct phy_device *phy_map[PHY_MAX_ADDR];
+
+	/* Pointer to an array of interrupts, each PHY's
+	 * interrupt at the index matching its address */
+	int *irq;
+};
+
+#define PHY_INTERRUPT_DISABLED 0x0
+#define PHY_INTERRUPT_ENABLED 0x80000000
+
+/* PHY state machine states:
+ *
+ * DOWN: PHY device and driver are not ready for anything.  probe
+ * should be called if and only if the PHY is in this state,
+ * given that the PHY device exists.
+ * - PHY driver probe function will, depending on the PHY, set
+ * the state to STARTING or READY
+ *
+ * STARTING:  PHY device is coming up, and the ethernet driver is
+ * not ready.  PHY drivers may set this in the probe function.
+ * If they do, they are responsible for making sure the state is
+ * eventually set to indicate whether the PHY is UP or READY,
+ * depending on the state when the PHY is done starting up.
+ * - PHY driver will set the state to READY
+ * - start will set the state to PENDING
+ *
+ * READY: PHY is ready to send and receive packets, but the
+ * controller is not.  By default, PHYs which do not implement
+ * probe will be set to this state by phy_probe().  If the PHY
+ * driver knows the PHY is ready, and the PHY state is STARTING,
+ * then it sets this STATE.
+ * - start will set the state to UP
+ *
+ * PENDING: PHY device is coming up, but the ethernet driver is
+ * ready.  phy_start will set this state if the PHY state is
+ * STARTING.
+ * - PHY driver will set the state to UP when the PHY is ready
+ *
+ * UP: The PHY and attached device are ready to do work.
+ * Interrupts should be started here.
+ * - timer moves to AN
+ *
+ * AN: The PHY is currently negotiating the link state.  Link is
+ * therefore down for now.  phy_timer will set this state when it
+ * detects the state is UP.  config_aneg will set this state
+ * whenever called with phydev->autoneg set to AUTONEG_ENABLE.
+ * - If autonegotiation finishes, but there's no link, it sets
+ *   the state to NOLINK.
+ * - If aneg finishes with link, it sets the state to RUNNING,
+ *   and calls adjust_link
+ * - If autonegotiation did not finish after an arbitrary amount
+ *   of time, autonegotiation should be tried again if the PHY
+ *   supports "magic" autonegotiation (back to AN)
+ * - If it didn't finish, and no magic_aneg, move to FORCING.
+ *
+ * NOLINK: PHY is up, but not currently plugged in.
+ * - If the timer notes that the link comes back, we move to RUNNING
+ * - config_aneg moves to AN
+ * - phy_stop moves to HALTED
+ *
+ * FORCING: PHY is being configured with forced settings
+ * - if link is up, move to RUNNING
+ * - If link is down, we drop to the next highest setting, and
+ *   retry (FORCING) after a timeout
+ * - phy_stop moves to HALTED
+ *
+ * RUNNING: PHY is currently up, running, and possibly sending
+ * and/or receiving packets
+ * - timer will set CHANGELINK if we're polling (this ensures the
+ *   link state is polled every other cycle of this state machine,
+ *   which makes it every other second)
+ * - irq will set CHANGELINK
+ * - config_aneg will set AN
+ * - phy_stop moves to HALTED
+ *
+ * CHANGELINK: PHY experienced a change in link state
+ * - timer moves to RUNNING if link
+ * - timer moves to NOLINK if the link is down
+ * - phy_stop moves to HALTED
+ *
+ * HALTED: PHY is up, but no polling or interrupts are done. Or
+ * PHY is in an error state.
+ *
+ * - phy_start moves to RESUMING
+ *
+ * RESUMING: PHY was halted, but now wants to run again.
+ * - If we are forcing, or aneg is done, timer moves to RUNNING
+ * - If aneg is not done, timer moves to AN
+ * - phy_stop moves to HALTED
+ */
+enum phy_state {
+	PHY_DOWN=0,
+	PHY_STARTING,
+	PHY_READY,
+	PHY_PENDING,
+	PHY_UP,
+	PHY_AN,
+	PHY_RUNNING,
+	PHY_NOLINK,
+	PHY_FORCING,
+	PHY_CHANGELINK,
+	PHY_HALTED,
+	PHY_RESUMING
+};
+
+/* phy_device: An instance of a PHY
+ *
+ * drv: Pointer to the driver for this PHY instance
+ * bus: Pointer to the bus this PHY is on
+ * dev: driver model device structure for this PHY
+ * phy_id: UID for this device found during discovery
+ * state: state of the PHY for management purposes
+ * dev_flags: Device-specific flags used by the PHY driver.
+ * addr: Bus address of PHY
+ * link_timeout: The number of timer firings to wait before the
+ * giving up on the current attempt at acquiring a link
+ * irq: IRQ number of the PHY's interrupt (-1 if none)
+ * phy_timer: The timer for handling the state machine
+ * phy_queue: A work_queue for the interrupt
+ * attached_dev: The attached enet driver's device instance ptr
+ * adjust_link: Callback for the enet controller to respond to
+ * changes in the link state.
+ * adjust_state: Callback for the enet driver to respond to
+ * changes in the state machine.
+ *
+ * speed, duplex, pause, supported, advertising, and
+ * autoneg are used like in mii_if_info
+ *
+ * interrupts currently only supports enabled or disabled,
+ * but could be changed in the future to support enabling
+ * and disabling specific interrupts
+ *
+ * Contains some infrastructure for polling and interrupt
+ * handling, as well as handling shifts in PHY hardware state
+ */
+struct phy_device {
+	/* Information about the PHY type */
+	/* And management functions */
+	struct phy_driver *drv;
+
+	struct mii_bus *bus;
+
+	struct device dev;
+
+	u32 phy_id;
+
+	enum phy_state state;
+
+	u32 dev_flags;
+
+	/* Bus address of the PHY (0-32) */
+	int addr;
+
+	/* forced speed & duplex (no autoneg)
+	 * partner speed & duplex & pause (autoneg)
+	 */
+	int speed;
+	int duplex;
+	int pause;
+	int asym_pause;
+
+	/* The most recently read link state */
+	int link;
+
+	/* Enabled Interrupts */
+	u32 interrupts;
+
+	/* Union of PHY and Attached devices' supported modes */
+	/* See mii.h for more info */
+	u32 supported;
+	u32 advertising;
+
+	int autoneg;
+
+	int link_timeout;
+
+	/* Interrupt number for this PHY
+	 * -1 means no interrupt */
+	int irq;
+
+	/* private data pointer */
+	/* For use by PHYs to maintain extra state */
+	void *priv;
+
+	/* Interrupt and Polling infrastructure */
+	struct work_struct phy_queue;
+	struct timer_list phy_timer;
+
+	spinlock_t lock;
+
+	struct net_device *attached_dev;
+
+	void (*adjust_link)(struct net_device *dev);
+
+	void (*adjust_state)(struct net_device *dev);
+};
+#define to_phy_device(d) container_of(d, struct phy_device, dev)
+
+/* struct phy_driver: Driver structure for a particular PHY type
+ *
+ * phy_id: The result of reading the UID registers of this PHY
+ *   type, and ANDing them with the phy_id_mask.  This driver
+ *   only works for PHYs with IDs which match this field
+ * name: The friendly name of this PHY type
+ * phy_id_mask: Defines the important bits of the phy_id
+ * features: A list of features (speed, duplex, etc) supported
+ *   by this PHY
+ * flags: A bitfield defining certain other features this PHY
+ *   supports (like interrupts)
+ *
+ * The drivers must implement config_aneg and read_status.  All
+ * other functions are optional. Note that none of these
+ * functions should be called from interrupt time.  The goal is
+ * for the bus read/write functions to be able to block when the
+ * bus transaction is happening, and be freed up by an interrupt
+ * (The MPC85xx has this ability, though it is not currently
+ * supported in the driver).
+ */
+struct phy_driver {
+	u32 phy_id;
+	char *name;
+	unsigned int phy_id_mask;
+	u32 features;
+	u32 flags;
+
+	/* Called to initialize the PHY,
+	 * including after a reset */
+	int (*config_init)(struct phy_device *phydev);
+
+	/* Called during discovery.  Used to set
+	 * up device-specific structures, if any */
+	int (*probe)(struct phy_device *phydev);
+
+	/* PHY Power Management */
+	int (*suspend)(struct phy_device *phydev);
+	int (*resume)(struct phy_device *phydev);
+
+	/* Configures the advertisement and resets
+	 * autonegotiation if phydev->autoneg is on,
+	 * forces the speed to the current settings in phydev
+	 * if phydev->autoneg is off */
+	int (*config_aneg)(struct phy_device *phydev);
+
+	/* Determines the negotiated speed and duplex */
+	int (*read_status)(struct phy_device *phydev);
+
+	/* Clears any pending interrupts */
+	int (*ack_interrupt)(struct phy_device *phydev);
+
+	/* Enables or disables interrupts */
+	int (*config_intr)(struct phy_device *phydev);
+
+	/* Clears up any memory if needed */
+	void (*remove)(struct phy_device *phydev);
+
+	struct device_driver driver;
+};
+#define to_phy_driver(d) container_of(d, struct phy_driver, driver)
+
+int phy_read(struct phy_device *phydev, u16 regnum);
+int phy_write(struct phy_device *phydev, u16 regnum, u16 val);
+struct phy_device* get_phy_device(struct mii_bus *bus, int addr);
+int phy_clear_interrupt(struct phy_device *phydev);
+int phy_config_interrupt(struct phy_device *phydev, u32 interrupts);
+struct phy_device * phy_attach(struct net_device *dev,
+		const char *phy_id, u32 flags);
+struct phy_device * phy_connect(struct net_device *dev, const char *phy_id,
+		void (*handler)(struct net_device *), u32 flags);
+void phy_disconnect(struct phy_device *phydev);
+void phy_detach(struct phy_device *phydev);
+void phy_start(struct phy_device *phydev);
+void phy_stop(struct phy_device *phydev);
+int phy_start_aneg(struct phy_device *phydev);
+
+int mdiobus_register(struct mii_bus *bus);
+void mdiobus_unregister(struct mii_bus *bus);
+void phy_sanitize_settings(struct phy_device *phydev);
+int phy_stop_interrupts(struct phy_device *phydev);
+
+static inline int phy_read_status(struct phy_device *phydev) {
+	return phydev->drv->read_status(phydev);
+}
+
+int genphy_config_advert(struct phy_device *phydev);
+int genphy_setup_forced(struct phy_device *phydev);
+int genphy_restart_aneg(struct phy_device *phydev);
+int genphy_config_aneg(struct phy_device *phydev);
+int genphy_update_link(struct phy_device *phydev);
+int genphy_read_status(struct phy_device *phydev);
+void phy_driver_unregister(struct phy_driver *drv);
+int phy_driver_register(struct phy_driver *new_driver);
+void phy_prepare_link(struct phy_device *phydev,
+		void (*adjust_link)(struct net_device *));
+void phy_start_machine(struct phy_device *phydev,
+		void (*handler)(struct net_device *));
+void phy_stop_machine(struct phy_device *phydev);
+int phy_ethtool_sset(struct phy_device *phydev, struct ethtool_cmd *cmd);
+int phy_ethtool_gset(struct phy_device *phydev, struct ethtool_cmd *cmd);
+int phy_mii_ioctl(struct phy_device *phydev,
+		struct mii_ioctl_data *mii_data, int cmd);
+int phy_start_interrupts(struct phy_device *phydev);
+void phy_print_status(struct phy_device *phydev);
+
+extern struct bus_type mdio_bus_type;
+extern struct phy_driver genphy_driver;
+#endif /* __PHY_H */