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path: root/drivers/net/phy/mdio_bus.c
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Diffstat (limited to 'drivers/net/phy/mdio_bus.c')
-rw-r--r--drivers/net/phy/mdio_bus.c612
1 files changed, 612 insertions, 0 deletions
diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c
new file mode 100644
index 000000000..095ef3fe3
--- /dev/null
+++ b/drivers/net/phy/mdio_bus.c
@@ -0,0 +1,612 @@
+/* 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.
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.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/device.h>
+#include <linux/of_device.h>
+#include <linux/of_mdio.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/mii.h>
+#include <linux/ethtool.h>
+#include <linux/phy.h>
+#include <linux/io.h>
+#include <linux/uaccess.h>
+
+#include <asm/irq.h>
+
+/**
+ * mdiobus_alloc_size - allocate a mii_bus structure
+ * @size: extra amount of memory to allocate for private storage.
+ * If non-zero, then bus->priv is points to that memory.
+ *
+ * Description: called by a bus driver to allocate an mii_bus
+ * structure to fill in.
+ */
+struct mii_bus *mdiobus_alloc_size(size_t size)
+{
+ struct mii_bus *bus;
+ size_t aligned_size = ALIGN(sizeof(*bus), NETDEV_ALIGN);
+ size_t alloc_size;
+
+ /* If we alloc extra space, it should be aligned */
+ if (size)
+ alloc_size = aligned_size + size;
+ else
+ alloc_size = sizeof(*bus);
+
+ bus = kzalloc(alloc_size, GFP_KERNEL);
+ if (bus) {
+ bus->state = MDIOBUS_ALLOCATED;
+ if (size)
+ bus->priv = (void *)bus + aligned_size;
+ }
+
+ return bus;
+}
+EXPORT_SYMBOL(mdiobus_alloc_size);
+
+static void _devm_mdiobus_free(struct device *dev, void *res)
+{
+ mdiobus_free(*(struct mii_bus **)res);
+}
+
+static int devm_mdiobus_match(struct device *dev, void *res, void *data)
+{
+ struct mii_bus **r = res;
+
+ if (WARN_ON(!r || !*r))
+ return 0;
+
+ return *r == data;
+}
+
+/**
+ * devm_mdiobus_alloc_size - Resource-managed mdiobus_alloc_size()
+ * @dev: Device to allocate mii_bus for
+ * @sizeof_priv: Space to allocate for private structure.
+ *
+ * Managed mdiobus_alloc_size. mii_bus allocated with this function is
+ * automatically freed on driver detach.
+ *
+ * If an mii_bus allocated with this function needs to be freed separately,
+ * devm_mdiobus_free() must be used.
+ *
+ * RETURNS:
+ * Pointer to allocated mii_bus on success, NULL on failure.
+ */
+struct mii_bus *devm_mdiobus_alloc_size(struct device *dev, int sizeof_priv)
+{
+ struct mii_bus **ptr, *bus;
+
+ ptr = devres_alloc(_devm_mdiobus_free, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return NULL;
+
+ /* use raw alloc_dr for kmalloc caller tracing */
+ bus = mdiobus_alloc_size(sizeof_priv);
+ if (bus) {
+ *ptr = bus;
+ devres_add(dev, ptr);
+ } else {
+ devres_free(ptr);
+ }
+
+ return bus;
+}
+EXPORT_SYMBOL_GPL(devm_mdiobus_alloc_size);
+
+/**
+ * devm_mdiobus_free - Resource-managed mdiobus_free()
+ * @dev: Device this mii_bus belongs to
+ * @bus: the mii_bus associated with the device
+ *
+ * Free mii_bus allocated with devm_mdiobus_alloc_size().
+ */
+void devm_mdiobus_free(struct device *dev, struct mii_bus *bus)
+{
+ int rc;
+
+ rc = devres_release(dev, _devm_mdiobus_free,
+ devm_mdiobus_match, bus);
+ WARN_ON(rc);
+}
+EXPORT_SYMBOL_GPL(devm_mdiobus_free);
+
+/**
+ * mdiobus_release - mii_bus device release callback
+ * @d: the target struct device that contains the mii_bus
+ *
+ * Description: called when the last reference to an mii_bus is
+ * dropped, to free the underlying memory.
+ */
+static void mdiobus_release(struct device *d)
+{
+ struct mii_bus *bus = to_mii_bus(d);
+ BUG_ON(bus->state != MDIOBUS_RELEASED &&
+ /* for compatibility with error handling in drivers */
+ bus->state != MDIOBUS_ALLOCATED);
+ kfree(bus);
+}
+
+static struct class mdio_bus_class = {
+ .name = "mdio_bus",
+ .dev_release = mdiobus_release,
+};
+
+#if IS_ENABLED(CONFIG_OF_MDIO)
+/* Helper function for of_mdio_find_bus */
+static int of_mdio_bus_match(struct device *dev, const void *mdio_bus_np)
+{
+ return dev->of_node == mdio_bus_np;
+}
+/**
+ * of_mdio_find_bus - Given an mii_bus node, find the mii_bus.
+ * @mdio_bus_np: Pointer to the mii_bus.
+ *
+ * Returns a pointer to the mii_bus, or NULL if none found.
+ *
+ * Because the association of a device_node and mii_bus is made via
+ * of_mdiobus_register(), the mii_bus cannot be found before it is
+ * registered with of_mdiobus_register().
+ *
+ */
+struct mii_bus *of_mdio_find_bus(struct device_node *mdio_bus_np)
+{
+ struct device *d;
+
+ if (!mdio_bus_np)
+ return NULL;
+
+ d = class_find_device(&mdio_bus_class, NULL, mdio_bus_np,
+ of_mdio_bus_match);
+
+ return d ? to_mii_bus(d) : NULL;
+}
+EXPORT_SYMBOL(of_mdio_find_bus);
+
+/* Walk the list of subnodes of a mdio bus and look for a node that matches the
+ * phy's address with its 'reg' property. If found, set the of_node pointer for
+ * the phy. This allows auto-probed pyh devices to be supplied with information
+ * passed in via DT.
+ */
+static void of_mdiobus_link_phydev(struct mii_bus *mdio,
+ struct phy_device *phydev)
+{
+ struct device *dev = &phydev->dev;
+ struct device_node *child;
+
+ if (dev->of_node || !mdio->dev.of_node)
+ return;
+
+ for_each_available_child_of_node(mdio->dev.of_node, child) {
+ int addr;
+ int ret;
+
+ ret = of_property_read_u32(child, "reg", &addr);
+ if (ret < 0) {
+ dev_err(dev, "%s has invalid PHY address\n",
+ child->full_name);
+ continue;
+ }
+
+ /* A PHY must have a reg property in the range [0-31] */
+ if (addr >= PHY_MAX_ADDR) {
+ dev_err(dev, "%s PHY address %i is too large\n",
+ child->full_name, addr);
+ continue;
+ }
+
+ if (addr == phydev->addr) {
+ dev->of_node = child;
+ return;
+ }
+ }
+}
+#else /* !IS_ENABLED(CONFIG_OF_MDIO) */
+static inline void of_mdiobus_link_phydev(struct mii_bus *mdio,
+ struct phy_device *phydev)
+{
+}
+#endif
+
+/**
+ * mdiobus_register - bring up all the PHYs on a given bus and attach them to bus
+ * @bus: target mii_bus
+ *
+ * Description: Called by a bus driver to bring up all the PHYs
+ * on a given bus, and attach them to the bus.
+ *
+ * Returns 0 on success or < 0 on error.
+ */
+int mdiobus_register(struct mii_bus *bus)
+{
+ int i, err;
+
+ if (NULL == bus || NULL == bus->name ||
+ NULL == bus->read || NULL == bus->write)
+ return -EINVAL;
+
+ BUG_ON(bus->state != MDIOBUS_ALLOCATED &&
+ bus->state != MDIOBUS_UNREGISTERED);
+
+ bus->dev.parent = bus->parent;
+ bus->dev.class = &mdio_bus_class;
+ bus->dev.groups = NULL;
+ dev_set_name(&bus->dev, "%s", bus->id);
+
+ err = device_register(&bus->dev);
+ if (err) {
+ pr_err("mii_bus %s failed to register\n", bus->id);
+ put_device(&bus->dev);
+ return -EINVAL;
+ }
+
+ mutex_init(&bus->mdio_lock);
+
+ if (bus->reset)
+ bus->reset(bus);
+
+ for (i = 0; i < PHY_MAX_ADDR; i++) {
+ if ((bus->phy_mask & (1 << i)) == 0) {
+ struct phy_device *phydev;
+
+ phydev = mdiobus_scan(bus, i);
+ if (IS_ERR(phydev)) {
+ err = PTR_ERR(phydev);
+ goto error;
+ }
+ }
+ }
+
+ bus->state = MDIOBUS_REGISTERED;
+ pr_info("%s: probed\n", bus->name);
+ return 0;
+
+error:
+ while (--i >= 0) {
+ if (bus->phy_map[i])
+ device_unregister(&bus->phy_map[i]->dev);
+ }
+ device_del(&bus->dev);
+ return err;
+}
+EXPORT_SYMBOL(mdiobus_register);
+
+void mdiobus_unregister(struct mii_bus *bus)
+{
+ int i;
+
+ BUG_ON(bus->state != MDIOBUS_REGISTERED);
+ bus->state = MDIOBUS_UNREGISTERED;
+
+ device_del(&bus->dev);
+ for (i = 0; i < PHY_MAX_ADDR; i++) {
+ if (bus->phy_map[i])
+ device_unregister(&bus->phy_map[i]->dev);
+ bus->phy_map[i] = NULL;
+ }
+}
+EXPORT_SYMBOL(mdiobus_unregister);
+
+/**
+ * mdiobus_free - free a struct mii_bus
+ * @bus: mii_bus to free
+ *
+ * This function releases the reference to the underlying device
+ * object in the mii_bus. If this is the last reference, the mii_bus
+ * will be freed.
+ */
+void mdiobus_free(struct mii_bus *bus)
+{
+ /* For compatibility with error handling in drivers. */
+ if (bus->state == MDIOBUS_ALLOCATED) {
+ kfree(bus);
+ return;
+ }
+
+ BUG_ON(bus->state != MDIOBUS_UNREGISTERED);
+ bus->state = MDIOBUS_RELEASED;
+
+ put_device(&bus->dev);
+}
+EXPORT_SYMBOL(mdiobus_free);
+
+struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr)
+{
+ struct phy_device *phydev;
+ int err;
+
+ phydev = get_phy_device(bus, addr, false);
+ if (IS_ERR(phydev) || phydev == NULL)
+ return phydev;
+
+ /*
+ * For DT, see if the auto-probed phy has a correspoding child
+ * in the bus node, and set the of_node pointer in this case.
+ */
+ of_mdiobus_link_phydev(bus, phydev);
+
+ err = phy_device_register(phydev);
+ if (err) {
+ phy_device_free(phydev);
+ return NULL;
+ }
+
+ return phydev;
+}
+EXPORT_SYMBOL(mdiobus_scan);
+
+/**
+ * mdiobus_read - Convenience function for reading a given MII mgmt register
+ * @bus: the mii_bus struct
+ * @addr: the phy address
+ * @regnum: register number to read
+ *
+ * NOTE: MUST NOT be called from interrupt context,
+ * because the bus read/write functions may wait for an interrupt
+ * to conclude the operation.
+ */
+int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
+{
+ int retval;
+
+ BUG_ON(in_interrupt());
+
+ mutex_lock(&bus->mdio_lock);
+ retval = bus->read(bus, addr, regnum);
+ mutex_unlock(&bus->mdio_lock);
+
+ return retval;
+}
+EXPORT_SYMBOL(mdiobus_read);
+
+/**
+ * mdiobus_write - Convenience function for writing a given MII mgmt register
+ * @bus: the mii_bus struct
+ * @addr: the phy address
+ * @regnum: register number to write
+ * @val: value to write to @regnum
+ *
+ * NOTE: MUST NOT be called from interrupt context,
+ * because the bus read/write functions may wait for an interrupt
+ * to conclude the operation.
+ */
+int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
+{
+ int err;
+
+ BUG_ON(in_interrupt());
+
+ mutex_lock(&bus->mdio_lock);
+ err = bus->write(bus, addr, regnum, val);
+ mutex_unlock(&bus->mdio_lock);
+
+ return err;
+}
+EXPORT_SYMBOL(mdiobus_write);
+
+/**
+ * mdio_bus_match - determine if given PHY driver supports the given PHY device
+ * @dev: target PHY device
+ * @drv: given PHY driver
+ *
+ * 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);
+
+ if (of_driver_match_device(dev, drv))
+ return 1;
+
+ if (phydrv->match_phy_device)
+ return phydrv->match_phy_device(phydev);
+
+ return (phydrv->phy_id & phydrv->phy_id_mask) ==
+ (phydev->phy_id & phydrv->phy_id_mask);
+}
+
+#ifdef CONFIG_PM
+
+static bool mdio_bus_phy_may_suspend(struct phy_device *phydev)
+{
+ struct device_driver *drv = phydev->dev.driver;
+ struct phy_driver *phydrv = to_phy_driver(drv);
+ struct net_device *netdev = phydev->attached_dev;
+
+ if (!drv || !phydrv->suspend)
+ return false;
+
+ /* PHY not attached? May suspend if the PHY has not already been
+ * suspended as part of a prior call to phy_disconnect() ->
+ * phy_detach() -> phy_suspend() because the parent netdev might be the
+ * MDIO bus driver and clock gated at this point.
+ */
+ if (!netdev)
+ return !phydev->suspended;
+
+ /* Don't suspend PHY if the attched netdev parent may wakeup.
+ * The parent may point to a PCI device, as in tg3 driver.
+ */
+ if (netdev->dev.parent && device_may_wakeup(netdev->dev.parent))
+ return false;
+
+ /* Also don't suspend PHY if the netdev itself may wakeup. This
+ * is the case for devices w/o underlaying pwr. mgmt. aware bus,
+ * e.g. SoC devices.
+ */
+ if (device_may_wakeup(&netdev->dev))
+ return false;
+
+ return true;
+}
+
+static int mdio_bus_suspend(struct device *dev)
+{
+ struct phy_device *phydev = to_phy_device(dev);
+
+ /* We must stop the state machine manually, otherwise it stops out of
+ * control, possibly with the phydev->lock held. Upon resume, netdev
+ * may call phy routines that try to grab the same lock, and that may
+ * lead to a deadlock.
+ */
+ if (phydev->attached_dev && phydev->adjust_link)
+ phy_stop_machine(phydev);
+
+ if (!mdio_bus_phy_may_suspend(phydev))
+ return 0;
+
+ return phy_suspend(phydev);
+}
+
+static int mdio_bus_resume(struct device *dev)
+{
+ struct phy_device *phydev = to_phy_device(dev);
+ int ret;
+
+ if (!mdio_bus_phy_may_suspend(phydev))
+ goto no_resume;
+
+ ret = phy_resume(phydev);
+ if (ret < 0)
+ return ret;
+
+no_resume:
+ if (phydev->attached_dev && phydev->adjust_link)
+ phy_start_machine(phydev);
+
+ return 0;
+}
+
+static int mdio_bus_restore(struct device *dev)
+{
+ struct phy_device *phydev = to_phy_device(dev);
+ struct net_device *netdev = phydev->attached_dev;
+ int ret;
+
+ if (!netdev)
+ return 0;
+
+ ret = phy_init_hw(phydev);
+ if (ret < 0)
+ return ret;
+
+ /* The PHY needs to renegotiate. */
+ phydev->link = 0;
+ phydev->state = PHY_UP;
+
+ phy_start_machine(phydev);
+
+ return 0;
+}
+
+static const struct dev_pm_ops mdio_bus_pm_ops = {
+ .suspend = mdio_bus_suspend,
+ .resume = mdio_bus_resume,
+ .freeze = mdio_bus_suspend,
+ .thaw = mdio_bus_resume,
+ .restore = mdio_bus_restore,
+};
+
+#define MDIO_BUS_PM_OPS (&mdio_bus_pm_ops)
+
+#else
+
+#define MDIO_BUS_PM_OPS NULL
+
+#endif /* CONFIG_PM */
+
+static ssize_t
+phy_id_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct phy_device *phydev = to_phy_device(dev);
+
+ return sprintf(buf, "0x%.8lx\n", (unsigned long)phydev->phy_id);
+}
+static DEVICE_ATTR_RO(phy_id);
+
+static ssize_t
+phy_interface_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct phy_device *phydev = to_phy_device(dev);
+ const char *mode = NULL;
+
+ if (phy_is_internal(phydev))
+ mode = "internal";
+ else
+ mode = phy_modes(phydev->interface);
+
+ return sprintf(buf, "%s\n", mode);
+}
+static DEVICE_ATTR_RO(phy_interface);
+
+static ssize_t
+phy_has_fixups_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct phy_device *phydev = to_phy_device(dev);
+
+ return sprintf(buf, "%d\n", phydev->has_fixups);
+}
+static DEVICE_ATTR_RO(phy_has_fixups);
+
+static struct attribute *mdio_dev_attrs[] = {
+ &dev_attr_phy_id.attr,
+ &dev_attr_phy_interface.attr,
+ &dev_attr_phy_has_fixups.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(mdio_dev);
+
+struct bus_type mdio_bus_type = {
+ .name = "mdio_bus",
+ .match = mdio_bus_match,
+ .pm = MDIO_BUS_PM_OPS,
+ .dev_groups = mdio_dev_groups,
+};
+EXPORT_SYMBOL(mdio_bus_type);
+
+int __init mdio_bus_init(void)
+{
+ int ret;
+
+ ret = class_register(&mdio_bus_class);
+ if (!ret) {
+ ret = bus_register(&mdio_bus_type);
+ if (ret)
+ class_unregister(&mdio_bus_class);
+ }
+
+ return ret;
+}
+
+void mdio_bus_exit(void)
+{
+ class_unregister(&mdio_bus_class);
+ bus_unregister(&mdio_bus_type);
+}