- 根目录:
- drivers
- usb
- phy
- phy.c
/*
* phy.c -- USB phy handling
*
* Copyright (C) 2004-2013 Texas Instruments
*
* 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/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>
static LIST_HEAD(phy_list);
static LIST_HEAD(phy_bind_list);
static DEFINE_SPINLOCK(phy_lock);
struct phy_devm {
struct usb_phy *phy;
struct notifier_block *nb;
};
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 *__usb_find_phy_dev(struct device *dev,
struct list_head *list, u8 index)
{
struct usb_phy_bind *phy_bind = NULL;
list_for_each_entry(phy_bind, list, list) {
if (!(strcmp(phy_bind->dev_name, dev_name(dev))) &&
phy_bind->index == index) {
if (phy_bind->phy)
return phy_bind->phy;
else
return ERR_PTR(-EPROBE_DEFER);
}
}
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 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;
}
/**
* 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 %s node\n", phandle,
dev->of_node->full_name);
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);
/**
* usb_get_phy_dev - find the USB PHY
* @dev - device that requests this phy
* @index - the index of the phy
*
* 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_dev(struct device *dev, u8 index)
{
struct usb_phy *phy = NULL;
unsigned long flags;
spin_lock_irqsave(&phy_lock, flags);
phy = __usb_find_phy_dev(dev, &phy_bind_list, index);
if (IS_ERR(phy) || !try_module_get(phy->dev->driver->owner)) {
dev_dbg(dev, "unable to find transceiver\n");
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_dev);
/**
* devm_usb_get_phy_dev - find the USB PHY using device ptr and index
* @dev - device that requests this phy
* @index - the index of the phy
*
* Gets the phy using usb_get_phy_dev(), 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_dev(struct device *dev, u8 index)
{
struct usb_phy **ptr, *phy;
ptr = devres_alloc(devm_usb_phy_release, sizeof(*ptr), GFP_KERNEL);
if (!ptr)
return NULL;
phy = usb_get_phy_dev(dev, index);
if (!IS_ERR(phy)) {
*ptr = phy;
devres_add(dev, ptr);
} else
devres_free(ptr);
return phy;
}
EXPORT_SYMBOL_GPL(devm_usb_get_phy_dev);
/**
* 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;
}
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);
/**
* 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)
{
struct usb_phy_bind *phy_bind;
unsigned long flags;
if (!x->dev) {
dev_err(x->dev, "no device provided for PHY\n");
return -EINVAL;
}
ATOMIC_INIT_NOTIFIER_HEAD(&x->notifier);
spin_lock_irqsave(&phy_lock, flags);
list_for_each_entry(phy_bind, &phy_bind_list, list)
if (!(strcmp(phy_bind->phy_dev_name, dev_name(x->dev))))
phy_bind->phy = x;
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;
struct usb_phy_bind *phy_bind;
spin_lock_irqsave(&phy_lock, flags);
if (x) {
list_for_each_entry(phy_bind, &phy_bind_list, list)
if (phy_bind->phy == x)
phy_bind->phy = NULL;
list_del(&x->head);
}
spin_unlock_irqrestore(&phy_lock, flags);
}
EXPORT_SYMBOL_GPL(usb_remove_phy);
/**
* usb_bind_phy - bind the phy and the controller that uses the phy
* @dev_name: the device name of the device that will bind to the phy
* @index: index to specify the port number
* @phy_dev_name: the device name of the phy
*
* Fills the phy_bind structure with the dev_name and phy_dev_name. This will
* be used when the phy driver registers the phy and when the controller
* requests this phy.
*
* To be used by platform specific initialization code.
*/
int usb_bind_phy(const char *dev_name, u8 index,
const char *phy_dev_name)
{
struct usb_phy_bind *phy_bind;
unsigned long flags;
phy_bind = kzalloc(sizeof(*phy_bind), GFP_KERNEL);
if (!phy_bind)
return -ENOMEM;
phy_bind->dev_name = dev_name;
phy_bind->phy_dev_name = phy_dev_name;
phy_bind->index = index;
spin_lock_irqsave(&phy_lock, flags);
list_add_tail(&phy_bind->list, &phy_bind_list);
spin_unlock_irqrestore(&phy_lock, flags);
return 0;
}
EXPORT_SYMBOL_GPL(usb_bind_phy);
/**
* usb_phy_set_event - set event to phy event
* @x: the phy returned by usb_get_phy();
*
* 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);