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, 173 insertions, 0 deletions

diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c
new file mode 100644
index 000000000000..e75103ba6f86
--- /dev/null
+++ b/drivers/net/phy/mdio_bus.c
@@ -0,0 +1,173 @@
+/*
+ * drivers/net/phy/mdio_bus.c
+ *
+ * MDIO Bus interface
+ *
+ * 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.
+ *
+ */
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/unistd.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/skbuff.h>
+#include <linux/spinlock.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/version.h>
+#include <linux/mii.h>
+#include <linux/ethtool.h>
+#include <linux/phy.h>
+
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/uaccess.h>
+
+/* mdiobus_register 
+ *
+ * description: Called by a bus driver to bring up all the PHYs
+ *   on a given bus, and attach them to the bus
+ */
+int mdiobus_register(struct mii_bus *bus)
+{
+	int i;
+	int err = 0;
+
+	spin_lock_init(&bus->mdio_lock);
+
+	if (NULL == bus || NULL == bus->name ||
+			NULL == bus->read ||
+			NULL == bus->write)
+		return -EINVAL;
+
+	if (bus->reset)
+		bus->reset(bus);
+
+	for (i = 0; i < PHY_MAX_ADDR; i++) {
+		struct phy_device *phydev;
+
+		phydev = get_phy_device(bus, i);
+
+		if (IS_ERR(phydev))
+			return PTR_ERR(phydev);
+
+		/* There's a PHY at this address
+		 * We need to set:
+		 * 1) IRQ
+		 * 2) bus_id
+		 * 3) parent
+		 * 4) bus
+		 * 5) mii_bus
+		 * And, we need to register it */
+		if (phydev) {
+			phydev->irq = bus->irq[i];
+
+			phydev->dev.parent = bus->dev;
+			phydev->dev.bus = &mdio_bus_type;
+			sprintf(phydev->dev.bus_id, "phy%d:%d", bus->id, i);
+
+			phydev->bus = bus;
+
+			err = device_register(&phydev->dev);
+
+			if (err)
+				printk(KERN_ERR "phy %d failed to register\n",
+						i);
+		}
+
+		bus->phy_map[i] = phydev;
+	}
+
+	pr_info("%s: probed\n", bus->name);
+
+	return err;
+}
+EXPORT_SYMBOL(mdiobus_register);
+
+void mdiobus_unregister(struct mii_bus *bus)
+{
+	int i;
+
+	for (i = 0; i < PHY_MAX_ADDR; i++) {
+		if (bus->phy_map[i]) {
+			device_unregister(&bus->phy_map[i]->dev);
+			kfree(bus->phy_map[i]);
+		}
+	}
+}
+EXPORT_SYMBOL(mdiobus_unregister);
+
+/* mdio_bus_match
+ *
+ * description: Given a PHY device, and a PHY driver, return 1 if
+ *   the driver supports the device.  Otherwise, return 0
+ */
+static int mdio_bus_match(struct device *dev, struct device_driver *drv)
+{
+	struct phy_device *phydev = to_phy_device(dev);
+	struct phy_driver *phydrv = to_phy_driver(drv);
+
+	return (phydrv->phy_id == (phydev->phy_id & phydrv->phy_id_mask));
+}
+
+/* Suspend and resume.  Copied from platform_suspend and
+ * platform_resume
+ */
+static int mdio_bus_suspend(struct device * dev, u32 state)
+{
+	int ret = 0;
+	struct device_driver *drv = dev->driver;
+
+	if (drv && drv->suspend) {
+		ret = drv->suspend(dev, state, SUSPEND_DISABLE);
+		if (ret == 0)
+			ret = drv->suspend(dev, state, SUSPEND_SAVE_STATE);
+		if (ret == 0)
+			ret = drv->suspend(dev, state, SUSPEND_POWER_DOWN);
+	}
+	return ret;
+}
+
+static int mdio_bus_resume(struct device * dev)
+{
+	int ret = 0;
+	struct device_driver *drv = dev->driver;
+
+	if (drv && drv->resume) {
+		ret = drv->resume(dev, RESUME_POWER_ON);
+		if (ret == 0)
+			ret = drv->resume(dev, RESUME_RESTORE_STATE);
+		if (ret == 0)
+			ret = drv->resume(dev, RESUME_ENABLE);
+	}
+	return ret;
+}
+
+struct bus_type mdio_bus_type = {
+	.name		= "mdio_bus",
+	.match		= mdio_bus_match,
+	.suspend	= mdio_bus_suspend,
+	.resume		= mdio_bus_resume,
+};
+
+static int __init mdio_bus_init(void)
+{
+	return bus_register(&mdio_bus_type);
+}
+
+subsys_initcall(mdio_bus_init);