Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 770 insertions, 0 deletions

diff --git a/drivers/usb/phy/phy.c b/drivers/usb/phy/phy.c
new file mode 100644
index 000000000..1b24492bb
--- /dev/null
+++ b/drivers/usb/phy/phy.c
@@ -0,0 +1,770 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * phy.c -- USB phy handling
+ *
+ * Copyright (C) 2004-2013 Texas Instruments
+ */
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/err.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+
+#include <linux/usb/phy.h>
+
+/* Default current range by charger type. */
+#define DEFAULT_SDP_CUR_MIN	2
+#define DEFAULT_SDP_CUR_MAX	500
+#define DEFAULT_SDP_CUR_MIN_SS	150
+#define DEFAULT_SDP_CUR_MAX_SS	900
+#define DEFAULT_DCP_CUR_MIN	500
+#define DEFAULT_DCP_CUR_MAX	5000
+#define DEFAULT_CDP_CUR_MIN	1500
+#define DEFAULT_CDP_CUR_MAX	5000
+#define DEFAULT_ACA_CUR_MIN	1500
+#define DEFAULT_ACA_CUR_MAX	5000
+
+static LIST_HEAD(phy_list);
+static DEFINE_SPINLOCK(phy_lock);
+
+struct phy_devm {
+	struct usb_phy *phy;
+	struct notifier_block *nb;
+};
+
+static const char *const usb_chger_type[] = {
+	[UNKNOWN_TYPE]			= "USB_CHARGER_UNKNOWN_TYPE",
+	[SDP_TYPE]			= "USB_CHARGER_SDP_TYPE",
+	[CDP_TYPE]			= "USB_CHARGER_CDP_TYPE",
+	[DCP_TYPE]			= "USB_CHARGER_DCP_TYPE",
+	[ACA_TYPE]			= "USB_CHARGER_ACA_TYPE",
+};
+
+static const char *const usb_chger_state[] = {
+	[USB_CHARGER_DEFAULT]	= "USB_CHARGER_DEFAULT",
+	[USB_CHARGER_PRESENT]	= "USB_CHARGER_PRESENT",
+	[USB_CHARGER_ABSENT]	= "USB_CHARGER_ABSENT",
+};
+
+static struct usb_phy *__usb_find_phy(struct list_head *list,
+	enum usb_phy_type type)
+{
+	struct usb_phy  *phy = NULL;
+
+	list_for_each_entry(phy, list, head) {
+		if (phy->type != type)
+			continue;
+
+		return phy;
+	}
+
+	return ERR_PTR(-ENODEV);
+}
+
+static struct usb_phy *__of_usb_find_phy(struct device_node *node)
+{
+	struct usb_phy  *phy;
+
+	if (!of_device_is_available(node))
+		return ERR_PTR(-ENODEV);
+
+	list_for_each_entry(phy, &phy_list, head) {
+		if (node != phy->dev->of_node)
+			continue;
+
+		return phy;
+	}
+
+	return ERR_PTR(-EPROBE_DEFER);
+}
+
+static struct usb_phy *__device_to_usb_phy(struct device *dev)
+{
+	struct usb_phy *usb_phy;
+
+	list_for_each_entry(usb_phy, &phy_list, head) {
+		if (usb_phy->dev == dev)
+			return usb_phy;
+	}
+
+	return NULL;
+}
+
+static void usb_phy_set_default_current(struct usb_phy *usb_phy)
+{
+	usb_phy->chg_cur.sdp_min = DEFAULT_SDP_CUR_MIN;
+	usb_phy->chg_cur.sdp_max = DEFAULT_SDP_CUR_MAX;
+	usb_phy->chg_cur.dcp_min = DEFAULT_DCP_CUR_MIN;
+	usb_phy->chg_cur.dcp_max = DEFAULT_DCP_CUR_MAX;
+	usb_phy->chg_cur.cdp_min = DEFAULT_CDP_CUR_MIN;
+	usb_phy->chg_cur.cdp_max = DEFAULT_CDP_CUR_MAX;
+	usb_phy->chg_cur.aca_min = DEFAULT_ACA_CUR_MIN;
+	usb_phy->chg_cur.aca_max = DEFAULT_ACA_CUR_MAX;
+}
+
+/**
+ * usb_phy_notify_charger_work - notify the USB charger state
+ * @work: the charger work to notify the USB charger state
+ *
+ * This work can be issued when USB charger state has been changed or
+ * USB charger current has been changed, then we can notify the current
+ * what can be drawn to power user and the charger state to userspace.
+ *
+ * If we get the charger type from extcon subsystem, we can notify the
+ * charger state to power user automatically by usb_phy_get_charger_type()
+ * issuing from extcon subsystem.
+ *
+ * If we get the charger type from ->charger_detect() instead of extcon
+ * subsystem, the usb phy driver should issue usb_phy_set_charger_state()
+ * to set charger state when the charger state has been changed.
+ */
+static void usb_phy_notify_charger_work(struct work_struct *work)
+{
+	struct usb_phy *usb_phy = container_of(work, struct usb_phy, chg_work);
+	unsigned int min, max;
+
+	switch (usb_phy->chg_state) {
+	case USB_CHARGER_PRESENT:
+		usb_phy_get_charger_current(usb_phy, &min, &max);
+
+		atomic_notifier_call_chain(&usb_phy->notifier, max, usb_phy);
+		break;
+	case USB_CHARGER_ABSENT:
+		usb_phy_set_default_current(usb_phy);
+
+		atomic_notifier_call_chain(&usb_phy->notifier, 0, usb_phy);
+		break;
+	default:
+		dev_warn(usb_phy->dev, "Unknown USB charger state: %d\n",
+			 usb_phy->chg_state);
+		return;
+	}
+
+	kobject_uevent(&usb_phy->dev->kobj, KOBJ_CHANGE);
+}
+
+static int usb_phy_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+	struct usb_phy *usb_phy;
+	char uchger_state[50] = { 0 };
+	char uchger_type[50] = { 0 };
+	unsigned long flags;
+
+	spin_lock_irqsave(&phy_lock, flags);
+	usb_phy = __device_to_usb_phy(dev);
+	spin_unlock_irqrestore(&phy_lock, flags);
+
+	if (!usb_phy)
+		return -ENODEV;
+
+	snprintf(uchger_state, ARRAY_SIZE(uchger_state),
+		 "USB_CHARGER_STATE=%s", usb_chger_state[usb_phy->chg_state]);
+
+	snprintf(uchger_type, ARRAY_SIZE(uchger_type),
+		 "USB_CHARGER_TYPE=%s", usb_chger_type[usb_phy->chg_type]);
+
+	if (add_uevent_var(env, uchger_state))
+		return -ENOMEM;
+
+	if (add_uevent_var(env, uchger_type))
+		return -ENOMEM;
+
+	return 0;
+}
+
+static void __usb_phy_get_charger_type(struct usb_phy *usb_phy)
+{
+	if (extcon_get_state(usb_phy->edev, EXTCON_CHG_USB_SDP) > 0) {
+		usb_phy->chg_type = SDP_TYPE;
+		usb_phy->chg_state = USB_CHARGER_PRESENT;
+	} else if (extcon_get_state(usb_phy->edev, EXTCON_CHG_USB_CDP) > 0) {
+		usb_phy->chg_type = CDP_TYPE;
+		usb_phy->chg_state = USB_CHARGER_PRESENT;
+	} else if (extcon_get_state(usb_phy->edev, EXTCON_CHG_USB_DCP) > 0) {
+		usb_phy->chg_type = DCP_TYPE;
+		usb_phy->chg_state = USB_CHARGER_PRESENT;
+	} else if (extcon_get_state(usb_phy->edev, EXTCON_CHG_USB_ACA) > 0) {
+		usb_phy->chg_type = ACA_TYPE;
+		usb_phy->chg_state = USB_CHARGER_PRESENT;
+	} else {
+		usb_phy->chg_type = UNKNOWN_TYPE;
+		usb_phy->chg_state = USB_CHARGER_ABSENT;
+	}
+
+	schedule_work(&usb_phy->chg_work);
+}
+
+/**
+ * usb_phy_get_charger_type - get charger type from extcon subsystem
+ * @nb: the notifier block to determine charger type
+ * @state: the cable state
+ * @data: private data
+ *
+ * Determin the charger type from extcon subsystem which also means the
+ * charger state has been chaned, then we should notify this event.
+ */
+static int usb_phy_get_charger_type(struct notifier_block *nb,
+				    unsigned long state, void *data)
+{
+	struct usb_phy *usb_phy = container_of(nb, struct usb_phy, type_nb);
+
+	__usb_phy_get_charger_type(usb_phy);
+	return NOTIFY_OK;
+}
+
+/**
+ * usb_phy_set_charger_current - set the USB charger current
+ * @usb_phy: the USB phy to be used
+ * @mA: the current need to be set
+ *
+ * Usually we only change the charger default current when USB finished the
+ * enumeration as one SDP charger. As one SDP charger, usb_phy_set_power()
+ * will issue this function to change charger current when after setting USB
+ * configuration, or suspend/resume USB. For other type charger, we should
+ * use the default charger current and we do not suggest to issue this function
+ * to change the charger current.
+ *
+ * When USB charger current has been changed, we need to notify the power users.
+ */
+void usb_phy_set_charger_current(struct usb_phy *usb_phy, unsigned int mA)
+{
+	switch (usb_phy->chg_type) {
+	case SDP_TYPE:
+		if (usb_phy->chg_cur.sdp_max == mA)
+			return;
+
+		usb_phy->chg_cur.sdp_max = (mA > DEFAULT_SDP_CUR_MAX_SS) ?
+			DEFAULT_SDP_CUR_MAX_SS : mA;
+		break;
+	case DCP_TYPE:
+		if (usb_phy->chg_cur.dcp_max == mA)
+			return;
+
+		usb_phy->chg_cur.dcp_max = (mA > DEFAULT_DCP_CUR_MAX) ?
+			DEFAULT_DCP_CUR_MAX : mA;
+		break;
+	case CDP_TYPE:
+		if (usb_phy->chg_cur.cdp_max == mA)
+			return;
+
+		usb_phy->chg_cur.cdp_max = (mA > DEFAULT_CDP_CUR_MAX) ?
+			DEFAULT_CDP_CUR_MAX : mA;
+		break;
+	case ACA_TYPE:
+		if (usb_phy->chg_cur.aca_max == mA)
+			return;
+
+		usb_phy->chg_cur.aca_max = (mA > DEFAULT_ACA_CUR_MAX) ?
+			DEFAULT_ACA_CUR_MAX : mA;
+		break;
+	default:
+		return;
+	}
+
+	schedule_work(&usb_phy->chg_work);
+}
+EXPORT_SYMBOL_GPL(usb_phy_set_charger_current);
+
+/**
+ * usb_phy_get_charger_current - get the USB charger current
+ * @usb_phy: the USB phy to be used
+ * @min: the minimum current
+ * @max: the maximum current
+ *
+ * Usually we will notify the maximum current to power user, but for some
+ * special case, power user also need the minimum current value. Then the
+ * power user can issue this function to get the suitable current.
+ */
+void usb_phy_get_charger_current(struct usb_phy *usb_phy,
+				 unsigned int *min, unsigned int *max)
+{
+	switch (usb_phy->chg_type) {
+	case SDP_TYPE:
+		*min = usb_phy->chg_cur.sdp_min;
+		*max = usb_phy->chg_cur.sdp_max;
+		break;
+	case DCP_TYPE:
+		*min = usb_phy->chg_cur.dcp_min;
+		*max = usb_phy->chg_cur.dcp_max;
+		break;
+	case CDP_TYPE:
+		*min = usb_phy->chg_cur.cdp_min;
+		*max = usb_phy->chg_cur.cdp_max;
+		break;
+	case ACA_TYPE:
+		*min = usb_phy->chg_cur.aca_min;
+		*max = usb_phy->chg_cur.aca_max;
+		break;
+	default:
+		*min = 0;
+		*max = 0;
+		break;
+	}
+}
+EXPORT_SYMBOL_GPL(usb_phy_get_charger_current);
+
+/**
+ * usb_phy_set_charger_state - set the USB charger state
+ * @usb_phy: the USB phy to be used
+ * @state: the new state need to be set for charger
+ *
+ * The usb phy driver can issue this function when the usb phy driver
+ * detected the charger state has been changed, in this case the charger
+ * type should be get from ->charger_detect().
+ */
+void usb_phy_set_charger_state(struct usb_phy *usb_phy,
+			       enum usb_charger_state state)
+{
+	if (usb_phy->chg_state == state || !usb_phy->charger_detect)
+		return;
+
+	usb_phy->chg_state = state;
+	if (usb_phy->chg_state == USB_CHARGER_PRESENT)
+		usb_phy->chg_type = usb_phy->charger_detect(usb_phy);
+	else
+		usb_phy->chg_type = UNKNOWN_TYPE;
+
+	schedule_work(&usb_phy->chg_work);
+}
+EXPORT_SYMBOL_GPL(usb_phy_set_charger_state);
+
+static void devm_usb_phy_release(struct device *dev, void *res)
+{
+	struct usb_phy *phy = *(struct usb_phy **)res;
+
+	usb_put_phy(phy);
+}
+
+static void devm_usb_phy_release2(struct device *dev, void *_res)
+{
+	struct phy_devm *res = _res;
+
+	if (res->nb)
+		usb_unregister_notifier(res->phy, res->nb);
+	usb_put_phy(res->phy);
+}
+
+static int devm_usb_phy_match(struct device *dev, void *res, void *match_data)
+{
+	struct usb_phy **phy = res;
+
+	return *phy == match_data;
+}
+
+static void usb_charger_init(struct usb_phy *usb_phy)
+{
+	usb_phy->chg_type = UNKNOWN_TYPE;
+	usb_phy->chg_state = USB_CHARGER_DEFAULT;
+	usb_phy_set_default_current(usb_phy);
+	INIT_WORK(&usb_phy->chg_work, usb_phy_notify_charger_work);
+}
+
+static int usb_add_extcon(struct usb_phy *x)
+{
+	int ret;
+
+	if (of_property_read_bool(x->dev->of_node, "extcon")) {
+		x->edev = extcon_get_edev_by_phandle(x->dev, 0);
+		if (IS_ERR(x->edev))
+			return PTR_ERR(x->edev);
+
+		x->id_edev = extcon_get_edev_by_phandle(x->dev, 1);
+		if (IS_ERR(x->id_edev)) {
+			x->id_edev = NULL;
+			dev_info(x->dev, "No separate ID extcon device\n");
+		}
+
+		if (x->vbus_nb.notifier_call) {
+			ret = devm_extcon_register_notifier(x->dev, x->edev,
+							    EXTCON_USB,
+							    &x->vbus_nb);
+			if (ret < 0) {
+				dev_err(x->dev,
+					"register VBUS notifier failed\n");
+				return ret;
+			}
+		} else {
+			x->type_nb.notifier_call = usb_phy_get_charger_type;
+
+			ret = devm_extcon_register_notifier(x->dev, x->edev,
+							    EXTCON_CHG_USB_SDP,
+							    &x->type_nb);
+			if (ret) {
+				dev_err(x->dev,
+					"register extcon USB SDP failed.\n");
+				return ret;
+			}
+
+			ret = devm_extcon_register_notifier(x->dev, x->edev,
+							    EXTCON_CHG_USB_CDP,
+							    &x->type_nb);
+			if (ret) {
+				dev_err(x->dev,
+					"register extcon USB CDP failed.\n");
+				return ret;
+			}
+
+			ret = devm_extcon_register_notifier(x->dev, x->edev,
+							    EXTCON_CHG_USB_DCP,
+							    &x->type_nb);
+			if (ret) {
+				dev_err(x->dev,
+					"register extcon USB DCP failed.\n");
+				return ret;
+			}
+
+			ret = devm_extcon_register_notifier(x->dev, x->edev,
+							    EXTCON_CHG_USB_ACA,
+							    &x->type_nb);
+			if (ret) {
+				dev_err(x->dev,
+					"register extcon USB ACA failed.\n");
+				return ret;
+			}
+		}
+
+		if (x->id_nb.notifier_call) {
+			struct extcon_dev *id_ext;
+
+			if (x->id_edev)
+				id_ext = x->id_edev;
+			else
+				id_ext = x->edev;
+
+			ret = devm_extcon_register_notifier(x->dev, id_ext,
+							    EXTCON_USB_HOST,
+							    &x->id_nb);
+			if (ret < 0) {
+				dev_err(x->dev,
+					"register ID notifier failed\n");
+				return ret;
+			}
+		}
+	}
+
+	if (x->type_nb.notifier_call)
+		__usb_phy_get_charger_type(x);
+
+	return 0;
+}
+
+/**
+ * devm_usb_get_phy - find the USB PHY
+ * @dev: device that requests this phy
+ * @type: the type of the phy the controller requires
+ *
+ * Gets the phy using usb_get_phy(), and associates a device with it using
+ * devres. On driver detach, release function is invoked on the devres data,
+ * then, devres data is freed.
+ *
+ * For use by USB host and peripheral drivers.
+ */
+struct usb_phy *devm_usb_get_phy(struct device *dev, enum usb_phy_type type)
+{
+	struct usb_phy **ptr, *phy;
+
+	ptr = devres_alloc(devm_usb_phy_release, sizeof(*ptr), GFP_KERNEL);
+	if (!ptr)
+		return ERR_PTR(-ENOMEM);
+
+	phy = usb_get_phy(type);
+	if (!IS_ERR(phy)) {
+		*ptr = phy;
+		devres_add(dev, ptr);
+	} else
+		devres_free(ptr);
+
+	return phy;
+}
+EXPORT_SYMBOL_GPL(devm_usb_get_phy);
+
+/**
+ * usb_get_phy - find the USB PHY
+ * @type: the type of the phy the controller requires
+ *
+ * Returns the phy driver, after getting a refcount to it; or
+ * -ENODEV if there is no such phy.  The caller is responsible for
+ * calling usb_put_phy() to release that count.
+ *
+ * For use by USB host and peripheral drivers.
+ */
+struct usb_phy *usb_get_phy(enum usb_phy_type type)
+{
+	struct usb_phy	*phy = NULL;
+	unsigned long	flags;
+
+	spin_lock_irqsave(&phy_lock, flags);
+
+	phy = __usb_find_phy(&phy_list, type);
+	if (IS_ERR(phy) || !try_module_get(phy->dev->driver->owner)) {
+		pr_debug("PHY: unable to find transceiver of type %s\n",
+			usb_phy_type_string(type));
+		if (!IS_ERR(phy))
+			phy = ERR_PTR(-ENODEV);
+
+		goto err0;
+	}
+
+	get_device(phy->dev);
+
+err0:
+	spin_unlock_irqrestore(&phy_lock, flags);
+
+	return phy;
+}
+EXPORT_SYMBOL_GPL(usb_get_phy);
+
+/**
+ * devm_usb_get_phy_by_node - find the USB PHY by device_node
+ * @dev: device that requests this phy
+ * @node: the device_node for the phy device.
+ * @nb: a notifier_block to register with the phy.
+ *
+ * Returns the phy driver associated with the given device_node,
+ * after getting a refcount to it, -ENODEV if there is no such phy or
+ * -EPROBE_DEFER if the device is not yet loaded. While at that, it
+ * also associates the device with
+ * the phy using devres. On driver detach, release function is invoked
+ * on the devres data, then, devres data is freed.
+ *
+ * For use by peripheral drivers for devices related to a phy,
+ * such as a charger.
+ */
+struct  usb_phy *devm_usb_get_phy_by_node(struct device *dev,
+					  struct device_node *node,
+					  struct notifier_block *nb)
+{
+	struct usb_phy	*phy = ERR_PTR(-ENOMEM);
+	struct phy_devm	*ptr;
+	unsigned long	flags;
+
+	ptr = devres_alloc(devm_usb_phy_release2, sizeof(*ptr), GFP_KERNEL);
+	if (!ptr) {
+		dev_dbg(dev, "failed to allocate memory for devres\n");
+		goto err0;
+	}
+
+	spin_lock_irqsave(&phy_lock, flags);
+
+	phy = __of_usb_find_phy(node);
+	if (IS_ERR(phy)) {
+		devres_free(ptr);
+		goto err1;
+	}
+
+	if (!try_module_get(phy->dev->driver->owner)) {
+		phy = ERR_PTR(-ENODEV);
+		devres_free(ptr);
+		goto err1;
+	}
+	if (nb)
+		usb_register_notifier(phy, nb);
+	ptr->phy = phy;
+	ptr->nb = nb;
+	devres_add(dev, ptr);
+
+	get_device(phy->dev);
+
+err1:
+	spin_unlock_irqrestore(&phy_lock, flags);
+
+err0:
+
+	return phy;
+}
+EXPORT_SYMBOL_GPL(devm_usb_get_phy_by_node);
+
+/**
+ * devm_usb_get_phy_by_phandle - find the USB PHY by phandle
+ * @dev: device that requests this phy
+ * @phandle: name of the property holding the phy phandle value
+ * @index: the index of the phy
+ *
+ * Returns the phy driver associated with the given phandle value,
+ * after getting a refcount to it, -ENODEV if there is no such phy or
+ * -EPROBE_DEFER if there is a phandle to the phy, but the device is
+ * not yet loaded. While at that, it also associates the device with
+ * the phy using devres. On driver detach, release function is invoked
+ * on the devres data, then, devres data is freed.
+ *
+ * For use by USB host and peripheral drivers.
+ */
+struct usb_phy *devm_usb_get_phy_by_phandle(struct device *dev,
+	const char *phandle, u8 index)
+{
+	struct device_node *node;
+	struct usb_phy	*phy;
+
+	if (!dev->of_node) {
+		dev_dbg(dev, "device does not have a device node entry\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	node = of_parse_phandle(dev->of_node, phandle, index);
+	if (!node) {
+		dev_dbg(dev, "failed to get %s phandle in %pOF node\n", phandle,
+			dev->of_node);
+		return ERR_PTR(-ENODEV);
+	}
+	phy = devm_usb_get_phy_by_node(dev, node, NULL);
+	of_node_put(node);
+	return phy;
+}
+EXPORT_SYMBOL_GPL(devm_usb_get_phy_by_phandle);
+
+/**
+ * devm_usb_put_phy - release the USB PHY
+ * @dev: device that wants to release this phy
+ * @phy: the phy returned by devm_usb_get_phy()
+ *
+ * destroys the devres associated with this phy and invokes usb_put_phy
+ * to release the phy.
+ *
+ * For use by USB host and peripheral drivers.
+ */
+void devm_usb_put_phy(struct device *dev, struct usb_phy *phy)
+{
+	int r;
+
+	r = devres_destroy(dev, devm_usb_phy_release, devm_usb_phy_match, phy);
+	dev_WARN_ONCE(dev, r, "couldn't find PHY resource\n");
+}
+EXPORT_SYMBOL_GPL(devm_usb_put_phy);
+
+/**
+ * usb_put_phy - release the USB PHY
+ * @x: the phy returned by usb_get_phy()
+ *
+ * Releases a refcount the caller received from usb_get_phy().
+ *
+ * For use by USB host and peripheral drivers.
+ */
+void usb_put_phy(struct usb_phy *x)
+{
+	if (x) {
+		struct module *owner = x->dev->driver->owner;
+
+		put_device(x->dev);
+		module_put(owner);
+	}
+}
+EXPORT_SYMBOL_GPL(usb_put_phy);
+
+/**
+ * usb_add_phy: declare the USB PHY
+ * @x: the USB phy to be used; or NULL
+ * @type: the type of this PHY
+ *
+ * This call is exclusively for use by phy drivers, which
+ * coordinate the activities of drivers for host and peripheral
+ * controllers, and in some cases for VBUS current regulation.
+ */
+int usb_add_phy(struct usb_phy *x, enum usb_phy_type type)
+{
+	int		ret = 0;
+	unsigned long	flags;
+	struct usb_phy	*phy;
+
+	if (x->type != USB_PHY_TYPE_UNDEFINED) {
+		dev_err(x->dev, "not accepting initialized PHY %s\n", x->label);
+		return -EINVAL;
+	}
+
+	usb_charger_init(x);
+	ret = usb_add_extcon(x);
+	if (ret)
+		return ret;
+
+	ATOMIC_INIT_NOTIFIER_HEAD(&x->notifier);
+
+	spin_lock_irqsave(&phy_lock, flags);
+
+	list_for_each_entry(phy, &phy_list, head) {
+		if (phy->type == type) {
+			ret = -EBUSY;
+			dev_err(x->dev, "transceiver type %s already exists\n",
+						usb_phy_type_string(type));
+			goto out;
+		}
+	}
+
+	x->type = type;
+	list_add_tail(&x->head, &phy_list);
+
+out:
+	spin_unlock_irqrestore(&phy_lock, flags);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(usb_add_phy);
+
+static struct device_type usb_phy_dev_type = {
+	.name = "usb_phy",
+	.uevent = usb_phy_uevent,
+};
+
+/**
+ * usb_add_phy_dev - declare the USB PHY
+ * @x: the USB phy to be used; or NULL
+ *
+ * This call is exclusively for use by phy drivers, which
+ * coordinate the activities of drivers for host and peripheral
+ * controllers, and in some cases for VBUS current regulation.
+ */
+int usb_add_phy_dev(struct usb_phy *x)
+{
+	unsigned long flags;
+	int ret;
+
+	if (!x->dev) {
+		dev_err(x->dev, "no device provided for PHY\n");
+		return -EINVAL;
+	}
+
+	usb_charger_init(x);
+	ret = usb_add_extcon(x);
+	if (ret)
+		return ret;
+
+	x->dev->type = &usb_phy_dev_type;
+
+	ATOMIC_INIT_NOTIFIER_HEAD(&x->notifier);
+
+	spin_lock_irqsave(&phy_lock, flags);
+	list_add_tail(&x->head, &phy_list);
+	spin_unlock_irqrestore(&phy_lock, flags);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(usb_add_phy_dev);
+
+/**
+ * usb_remove_phy - remove the OTG PHY
+ * @x: the USB OTG PHY to be removed;
+ *
+ * This reverts the effects of usb_add_phy
+ */
+void usb_remove_phy(struct usb_phy *x)
+{
+	unsigned long	flags;
+
+	spin_lock_irqsave(&phy_lock, flags);
+	if (x)
+		list_del(&x->head);
+	spin_unlock_irqrestore(&phy_lock, flags);
+}
+EXPORT_SYMBOL_GPL(usb_remove_phy);
+
+/**
+ * usb_phy_set_event - set event to phy event
+ * @x: the phy returned by usb_get_phy();
+ * @event: event to set
+ *
+ * This sets event to phy event
+ */
+void usb_phy_set_event(struct usb_phy *x, unsigned long event)
+{
+	x->last_event = event;
+}
+EXPORT_SYMBOL_GPL(usb_phy_set_event);