// 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(const 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(const struct device *dev, struct kobj_uevent_env *env)
{
const 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 const 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);
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