net: phy: Move of_mdio from drivers/of to drivers/net/mdio

Better place for of_mdio.c is drivers/net/mdio.
Move of_mdio.c from drivers/of to drivers/net/mdio

Signed-off-by: Calvin Johnson <calvin.johnson@oss.nxp.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

3 files changed, 602 insertions, 0 deletions

diff --git a/drivers/net/mdio/Kconfig b/drivers/net/mdio/Kconfig
index 27a2a4a3d943..a10cc460d7cf 100644
--- a/drivers/net/mdio/Kconfig
+++ b/drivers/net/mdio/Kconfig
@@ -19,6 +19,14 @@ config MDIO_BUS
 	  reflects whether the mdio_bus/mdio_device code is built as a
 	  loadable module or built-in.
 
+config OF_MDIO
+	def_tristate PHYLIB
+	depends on OF
+	depends on PHYLIB
+	select FIXED_PHY
+	help
+	  OpenFirmware MDIO bus (Ethernet PHY) accessors
+
 if MDIO_BUS
 
 config MDIO_DEVRES
diff --git a/drivers/net/mdio/Makefile b/drivers/net/mdio/Makefile
index 14d1beb633c9..5c498dde463f 100644
--- a/drivers/net/mdio/Makefile
+++ b/drivers/net/mdio/Makefile
@@ -1,6 +1,8 @@
 # SPDX-License-Identifier: GPL-2.0
 # Makefile for Linux MDIO bus drivers
 
+obj-$(CONFIG_OF_MDIO)	+= of_mdio.o
+
 obj-$(CONFIG_MDIO_ASPEED)		+= mdio-aspeed.o
 obj-$(CONFIG_MDIO_BCM_IPROC)		+= mdio-bcm-iproc.o
 obj-$(CONFIG_MDIO_BCM_UNIMAC)		+= mdio-bcm-unimac.o
diff --git a/drivers/net/mdio/of_mdio.c b/drivers/net/mdio/of_mdio.c
new file mode 100644
index 000000000000..4daf94bb56a5
--- /dev/null
+++ b/drivers/net/mdio/of_mdio.c
@@ -0,0 +1,592 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * OF helpers for the MDIO (Ethernet PHY) API
+ *
+ * Copyright (c) 2009 Secret Lab Technologies, Ltd.
+ *
+ * This file provides helper functions for extracting PHY device information
+ * out of the OpenFirmware device tree and using it to populate an mii_bus.
+ */
+
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/netdevice.h>
+#include <linux/err.h>
+#include <linux/phy.h>
+#include <linux/phy_fixed.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_mdio.h>
+#include <linux/of_net.h>
+#include <linux/module.h>
+
+#define DEFAULT_GPIO_RESET_DELAY	10	/* in microseconds */
+
+MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
+MODULE_LICENSE("GPL");
+
+/* Extract the clause 22 phy ID from the compatible string of the form
+ * ethernet-phy-idAAAA.BBBB */
+static int of_get_phy_id(struct device_node *device, u32 *phy_id)
+{
+	struct property *prop;
+	const char *cp;
+	unsigned int upper, lower;
+
+	of_property_for_each_string(device, "compatible", prop, cp) {
+		if (sscanf(cp, "ethernet-phy-id%4x.%4x", &upper, &lower) == 2) {
+			*phy_id = ((upper & 0xFFFF) << 16) | (lower & 0xFFFF);
+			return 0;
+		}
+	}
+	return -EINVAL;
+}
+
+static struct mii_timestamper *of_find_mii_timestamper(struct device_node *node)
+{
+	struct of_phandle_args arg;
+	int err;
+
+	err = of_parse_phandle_with_fixed_args(node, "timestamper", 1, 0, &arg);
+
+	if (err == -ENOENT)
+		return NULL;
+	else if (err)
+		return ERR_PTR(err);
+
+	if (arg.args_count != 1)
+		return ERR_PTR(-EINVAL);
+
+	return register_mii_timestamper(arg.np, arg.args[0]);
+}
+
+int of_mdiobus_phy_device_register(struct mii_bus *mdio, struct phy_device *phy,
+			      struct device_node *child, u32 addr)
+{
+	int rc;
+
+	rc = of_irq_get(child, 0);
+	if (rc == -EPROBE_DEFER)
+		return rc;
+
+	if (rc > 0) {
+		phy->irq = rc;
+		mdio->irq[addr] = rc;
+	} else {
+		phy->irq = mdio->irq[addr];
+	}
+
+	if (of_property_read_bool(child, "broken-turn-around"))
+		mdio->phy_ignore_ta_mask |= 1 << addr;
+
+	of_property_read_u32(child, "reset-assert-us",
+			     &phy->mdio.reset_assert_delay);
+	of_property_read_u32(child, "reset-deassert-us",
+			     &phy->mdio.reset_deassert_delay);
+
+	/* Associate the OF node with the device structure so it
+	 * can be looked up later */
+	of_node_get(child);
+	phy->mdio.dev.of_node = child;
+	phy->mdio.dev.fwnode = of_fwnode_handle(child);
+
+	/* All data is now stored in the phy struct;
+	 * register it */
+	rc = phy_device_register(phy);
+	if (rc) {
+		of_node_put(child);
+		return rc;
+	}
+
+	dev_dbg(&mdio->dev, "registered phy %pOFn at address %i\n",
+		child, addr);
+	return 0;
+}
+EXPORT_SYMBOL(of_mdiobus_phy_device_register);
+
+static int of_mdiobus_register_phy(struct mii_bus *mdio,
+				    struct device_node *child, u32 addr)
+{
+	struct mii_timestamper *mii_ts;
+	struct phy_device *phy;
+	bool is_c45;
+	int rc;
+	u32 phy_id;
+
+	mii_ts = of_find_mii_timestamper(child);
+	if (IS_ERR(mii_ts))
+		return PTR_ERR(mii_ts);
+
+	is_c45 = of_device_is_compatible(child,
+					 "ethernet-phy-ieee802.3-c45");
+
+	if (!is_c45 && !of_get_phy_id(child, &phy_id))
+		phy = phy_device_create(mdio, addr, phy_id, 0, NULL);
+	else
+		phy = get_phy_device(mdio, addr, is_c45);
+	if (IS_ERR(phy)) {
+		if (mii_ts)
+			unregister_mii_timestamper(mii_ts);
+		return PTR_ERR(phy);
+	}
+
+	rc = of_mdiobus_phy_device_register(mdio, phy, child, addr);
+	if (rc) {
+		if (mii_ts)
+			unregister_mii_timestamper(mii_ts);
+		phy_device_free(phy);
+		return rc;
+	}
+
+	/* phy->mii_ts may already be defined by the PHY driver. A
+	 * mii_timestamper probed via the device tree will still have
+	 * precedence.
+	 */
+	if (mii_ts)
+		phy->mii_ts = mii_ts;
+
+	return 0;
+}
+
+static int of_mdiobus_register_device(struct mii_bus *mdio,
+				      struct device_node *child, u32 addr)
+{
+	struct mdio_device *mdiodev;
+	int rc;
+
+	mdiodev = mdio_device_create(mdio, addr);
+	if (IS_ERR(mdiodev))
+		return PTR_ERR(mdiodev);
+
+	/* Associate the OF node with the device structure so it
+	 * can be looked up later.
+	 */
+	of_node_get(child);
+	mdiodev->dev.of_node = child;
+	mdiodev->dev.fwnode = of_fwnode_handle(child);
+
+	/* All data is now stored in the mdiodev struct; register it. */
+	rc = mdio_device_register(mdiodev);
+	if (rc) {
+		mdio_device_free(mdiodev);
+		of_node_put(child);
+		return rc;
+	}
+
+	dev_dbg(&mdio->dev, "registered mdio device %pOFn at address %i\n",
+		child, addr);
+	return 0;
+}
+
+/* The following is a list of PHY compatible strings which appear in
+ * some DTBs. The compatible string is never matched against a PHY
+ * driver, so is pointless. We only expect devices which are not PHYs
+ * to have a compatible string, so they can be matched to an MDIO
+ * driver.  Encourage users to upgrade their DT blobs to remove these.
+ */
+static const struct of_device_id whitelist_phys[] = {
+	{ .compatible = "brcm,40nm-ephy" },
+	{ .compatible = "broadcom,bcm5241" },
+	{ .compatible = "marvell,88E1111", },
+	{ .compatible = "marvell,88e1116", },
+	{ .compatible = "marvell,88e1118", },
+	{ .compatible = "marvell,88e1145", },
+	{ .compatible = "marvell,88e1149r", },
+	{ .compatible = "marvell,88e1310", },
+	{ .compatible = "marvell,88E1510", },
+	{ .compatible = "marvell,88E1514", },
+	{ .compatible = "moxa,moxart-rtl8201cp", },
+	{}
+};
+
+/*
+ * Return true if the child node is for a phy. It must either:
+ * o Compatible string of "ethernet-phy-idX.X"
+ * o Compatible string of "ethernet-phy-ieee802.3-c45"
+ * o Compatible string of "ethernet-phy-ieee802.3-c22"
+ * o In the white list above (and issue a warning)
+ * o No compatibility string
+ *
+ * A device which is not a phy is expected to have a compatible string
+ * indicating what sort of device it is.
+ */
+bool of_mdiobus_child_is_phy(struct device_node *child)
+{
+	u32 phy_id;
+
+	if (of_get_phy_id(child, &phy_id) != -EINVAL)
+		return true;
+
+	if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c45"))
+		return true;
+
+	if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c22"))
+		return true;
+
+	if (of_match_node(whitelist_phys, child)) {
+		pr_warn(FW_WARN
+			"%pOF: Whitelisted compatible string. Please remove\n",
+			child);
+		return true;
+	}
+
+	if (!of_find_property(child, "compatible", NULL))
+		return true;
+
+	return false;
+}
+EXPORT_SYMBOL(of_mdiobus_child_is_phy);
+
+/**
+ * of_mdiobus_register - Register mii_bus and create PHYs from the device tree
+ * @mdio: pointer to mii_bus structure
+ * @np: pointer to device_node of MDIO bus.
+ *
+ * This function registers the mii_bus structure and registers a phy_device
+ * for each child node of @np.
+ */
+int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
+{
+	struct device_node *child;
+	bool scanphys = false;
+	int addr, rc;
+
+	if (!np)
+		return mdiobus_register(mdio);
+
+	/* Do not continue if the node is disabled */
+	if (!of_device_is_available(np))
+		return -ENODEV;
+
+	/* Mask out all PHYs from auto probing.  Instead the PHYs listed in
+	 * the device tree are populated after the bus has been registered */
+	mdio->phy_mask = ~0;
+
+	mdio->dev.of_node = np;
+	mdio->dev.fwnode = of_fwnode_handle(np);
+
+	/* Get bus level PHY reset GPIO details */
+	mdio->reset_delay_us = DEFAULT_GPIO_RESET_DELAY;
+	of_property_read_u32(np, "reset-delay-us", &mdio->reset_delay_us);
+	mdio->reset_post_delay_us = 0;
+	of_property_read_u32(np, "reset-post-delay-us", &mdio->reset_post_delay_us);
+
+	/* Register the MDIO bus */
+	rc = mdiobus_register(mdio);
+	if (rc)
+		return rc;
+
+	/* Loop over the child nodes and register a phy_device for each phy */
+	for_each_available_child_of_node(np, child) {
+		addr = of_mdio_parse_addr(&mdio->dev, child);
+		if (addr < 0) {
+			scanphys = true;
+			continue;
+		}
+
+		if (of_mdiobus_child_is_phy(child))
+			rc = of_mdiobus_register_phy(mdio, child, addr);
+		else
+			rc = of_mdiobus_register_device(mdio, child, addr);
+
+		if (rc == -ENODEV)
+			dev_err(&mdio->dev,
+				"MDIO device at address %d is missing.\n",
+				addr);
+		else if (rc)
+			goto unregister;
+	}
+
+	if (!scanphys)
+		return 0;
+
+	/* auto scan for PHYs with empty reg property */
+	for_each_available_child_of_node(np, child) {
+		/* Skip PHYs with reg property set */
+		if (of_find_property(child, "reg", NULL))
+			continue;
+
+		for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
+			/* skip already registered PHYs */
+			if (mdiobus_is_registered_device(mdio, addr))
+				continue;
+
+			/* be noisy to encourage people to set reg property */
+			dev_info(&mdio->dev, "scan phy %pOFn at address %i\n",
+				 child, addr);
+
+			if (of_mdiobus_child_is_phy(child)) {
+				/* -ENODEV is the return code that PHYLIB has
+				 * standardized on to indicate that bus
+				 * scanning should continue.
+				 */
+				rc = of_mdiobus_register_phy(mdio, child, addr);
+				if (!rc)
+					break;
+				if (rc != -ENODEV)
+					goto unregister;
+			}
+		}
+	}
+
+	return 0;
+
+unregister:
+	mdiobus_unregister(mdio);
+	return rc;
+}
+EXPORT_SYMBOL(of_mdiobus_register);
+
+/**
+ * of_mdio_find_device - Given a device tree node, find the mdio_device
+ * @np: pointer to the mdio_device's device tree node
+ *
+ * If successful, returns a pointer to the mdio_device with the embedded
+ * struct device refcount incremented by one, or NULL on failure.
+ * The caller should call put_device() on the mdio_device after its use
+ */
+struct mdio_device *of_mdio_find_device(struct device_node *np)
+{
+	struct device *d;
+
+	if (!np)
+		return NULL;
+
+	d = bus_find_device_by_of_node(&mdio_bus_type, np);
+	if (!d)
+		return NULL;
+
+	return to_mdio_device(d);
+}
+EXPORT_SYMBOL(of_mdio_find_device);
+
+/**
+ * of_phy_find_device - Give a PHY node, find the phy_device
+ * @phy_np: Pointer to the phy's device tree node
+ *
+ * If successful, returns a pointer to the phy_device with the embedded
+ * struct device refcount incremented by one, or NULL on failure.
+ */
+struct phy_device *of_phy_find_device(struct device_node *phy_np)
+{
+	struct mdio_device *mdiodev;
+
+	mdiodev = of_mdio_find_device(phy_np);
+	if (!mdiodev)
+		return NULL;
+
+	if (mdiodev->flags & MDIO_DEVICE_FLAG_PHY)
+		return to_phy_device(&mdiodev->dev);
+
+	put_device(&mdiodev->dev);
+
+	return NULL;
+}
+EXPORT_SYMBOL(of_phy_find_device);
+
+/**
+ * of_phy_connect - Connect to the phy described in the device tree
+ * @dev: pointer to net_device claiming the phy
+ * @phy_np: Pointer to device tree node for the PHY
+ * @hndlr: Link state callback for the network device
+ * @flags: flags to pass to the PHY
+ * @iface: PHY data interface type
+ *
+ * If successful, returns a pointer to the phy_device with the embedded
+ * struct device refcount incremented by one, or NULL on failure. The
+ * refcount must be dropped by calling phy_disconnect() or phy_detach().
+ */
+struct phy_device *of_phy_connect(struct net_device *dev,
+				  struct device_node *phy_np,
+				  void (*hndlr)(struct net_device *), u32 flags,
+				  phy_interface_t iface)
+{
+	struct phy_device *phy = of_phy_find_device(phy_np);
+	int ret;
+
+	if (!phy)
+		return NULL;
+
+	phy->dev_flags |= flags;
+
+	ret = phy_connect_direct(dev, phy, hndlr, iface);
+
+	/* refcount is held by phy_connect_direct() on success */
+	put_device(&phy->mdio.dev);
+
+	return ret ? NULL : phy;
+}
+EXPORT_SYMBOL(of_phy_connect);
+
+/**
+ * of_phy_get_and_connect
+ * - Get phy node and connect to the phy described in the device tree
+ * @dev: pointer to net_device claiming the phy
+ * @np: Pointer to device tree node for the net_device claiming the phy
+ * @hndlr: Link state callback for the network device
+ *
+ * If successful, returns a pointer to the phy_device with the embedded
+ * struct device refcount incremented by one, or NULL on failure. The
+ * refcount must be dropped by calling phy_disconnect() or phy_detach().
+ */
+struct phy_device *of_phy_get_and_connect(struct net_device *dev,
+					  struct device_node *np,
+					  void (*hndlr)(struct net_device *))
+{
+	phy_interface_t iface;
+	struct device_node *phy_np;
+	struct phy_device *phy;
+	int ret;
+
+	ret = of_get_phy_mode(np, &iface);
+	if (ret)
+		return NULL;
+	if (of_phy_is_fixed_link(np)) {
+		ret = of_phy_register_fixed_link(np);
+		if (ret < 0) {
+			netdev_err(dev, "broken fixed-link specification\n");
+			return NULL;
+		}
+		phy_np = of_node_get(np);
+	} else {
+		phy_np = of_parse_phandle(np, "phy-handle", 0);
+		if (!phy_np)
+			return NULL;
+	}
+
+	phy = of_phy_connect(dev, phy_np, hndlr, 0, iface);
+
+	of_node_put(phy_np);
+
+	return phy;
+}
+EXPORT_SYMBOL(of_phy_get_and_connect);
+
+/**
+ * of_phy_attach - Attach to a PHY without starting the state machine
+ * @dev: pointer to net_device claiming the phy
+ * @phy_np: Node pointer for the PHY
+ * @flags: flags to pass to the PHY
+ * @iface: PHY data interface type
+ *
+ * If successful, returns a pointer to the phy_device with the embedded
+ * struct device refcount incremented by one, or NULL on failure. The
+ * refcount must be dropped by calling phy_disconnect() or phy_detach().
+ */
+struct phy_device *of_phy_attach(struct net_device *dev,
+				 struct device_node *phy_np, u32 flags,
+				 phy_interface_t iface)
+{
+	struct phy_device *phy = of_phy_find_device(phy_np);
+	int ret;
+
+	if (!phy)
+		return NULL;
+
+	ret = phy_attach_direct(dev, phy, flags, iface);
+
+	/* refcount is held by phy_attach_direct() on success */
+	put_device(&phy->mdio.dev);
+
+	return ret ? NULL : phy;
+}
+EXPORT_SYMBOL(of_phy_attach);
+
+/*
+ * of_phy_is_fixed_link() and of_phy_register_fixed_link() must
+ * support two DT bindings:
+ * - the old DT binding, where 'fixed-link' was a property with 5
+ *   cells encoding various informations about the fixed PHY
+ * - the new DT binding, where 'fixed-link' is a sub-node of the
+ *   Ethernet device.
+ */
+bool of_phy_is_fixed_link(struct device_node *np)
+{
+	struct device_node *dn;
+	int len, err;
+	const char *managed;
+
+	/* New binding */
+	dn = of_get_child_by_name(np, "fixed-link");
+	if (dn) {
+		of_node_put(dn);
+		return true;
+	}
+
+	err = of_property_read_string(np, "managed", &managed);
+	if (err == 0 && strcmp(managed, "auto") != 0)
+		return true;
+
+	/* Old binding */
+	if (of_get_property(np, "fixed-link", &len) &&
+	    len == (5 * sizeof(__be32)))
+		return true;
+
+	return false;
+}
+EXPORT_SYMBOL(of_phy_is_fixed_link);
+
+int of_phy_register_fixed_link(struct device_node *np)
+{
+	struct fixed_phy_status status = {};
+	struct device_node *fixed_link_node;
+	u32 fixed_link_prop[5];
+	const char *managed;
+
+	if (of_property_read_string(np, "managed", &managed) == 0 &&
+	    strcmp(managed, "in-band-status") == 0) {
+		/* status is zeroed, namely its .link member */
+		goto register_phy;
+	}
+
+	/* New binding */
+	fixed_link_node = of_get_child_by_name(np, "fixed-link");
+	if (fixed_link_node) {
+		status.link = 1;
+		status.duplex = of_property_read_bool(fixed_link_node,
+						      "full-duplex");
+		if (of_property_read_u32(fixed_link_node, "speed",
+					 &status.speed)) {
+			of_node_put(fixed_link_node);
+			return -EINVAL;
+		}
+		status.pause = of_property_read_bool(fixed_link_node, "pause");
+		status.asym_pause = of_property_read_bool(fixed_link_node,
+							  "asym-pause");
+		of_node_put(fixed_link_node);
+
+		goto register_phy;
+	}
+
+	/* Old binding */
+	if (of_property_read_u32_array(np, "fixed-link", fixed_link_prop,
+				       ARRAY_SIZE(fixed_link_prop)) == 0) {
+		status.link = 1;
+		status.duplex = fixed_link_prop[1];
+		status.speed  = fixed_link_prop[2];
+		status.pause  = fixed_link_prop[3];
+		status.asym_pause = fixed_link_prop[4];
+		goto register_phy;
+	}
+
+	return -ENODEV;
+
+register_phy:
+	return PTR_ERR_OR_ZERO(fixed_phy_register(PHY_POLL, &status, np));
+}
+EXPORT_SYMBOL(of_phy_register_fixed_link);
+
+void of_phy_deregister_fixed_link(struct device_node *np)
+{
+	struct phy_device *phydev;
+
+	phydev = of_phy_find_device(np);
+	if (!phydev)
+		return;
+
+	fixed_phy_unregister(phydev);
+
+	put_device(&phydev->mdio.dev);	/* of_phy_find_device() */
+	phy_device_free(phydev);	/* fixed_phy_register() */
+}
+EXPORT_SYMBOL(of_phy_deregister_fixed_link);