diff options
Diffstat (limited to 'drivers/usb/phy/phy.c')
-rw-r--r-- | drivers/usb/phy/phy.c | 438 |
1 files changed, 438 insertions, 0 deletions
diff --git a/drivers/usb/phy/phy.c b/drivers/usb/phy/phy.c new file mode 100644 index 0000000..f52c006 --- /dev/null +++ b/drivers/usb/phy/phy.c @@ -0,0 +1,438 @@ +/* + * 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); + +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; + + list_for_each_entry(phy, &phy_list, head) { + if (node != phy->dev->of_node) + continue; + + return phy; + } + + return ERR_PTR(-ENODEV); +} + +static void devm_usb_phy_release(struct device *dev, void *res) +{ + struct usb_phy *phy = *(struct usb_phy **)res; + + usb_put_phy(phy); +} + +static int devm_usb_phy_match(struct device *dev, void *res, void *match_data) +{ + return res == 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 NULL; + + 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_err("unable to find transceiver of type %s\n", + usb_phy_type_string(type)); + 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_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 usb_phy *phy = ERR_PTR(-ENOMEM), **ptr; + unsigned long flags; + struct device_node *node; + + 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); + } + + ptr = devres_alloc(devm_usb_phy_release, 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) || !try_module_get(phy->dev->driver->owner)) { + phy = ERR_PTR(-EPROBE_DEFER); + devres_free(ptr); + goto err1; + } + + *ptr = phy; + devres_add(dev, ptr); + + get_device(phy->dev); + +err1: + spin_unlock_irqrestore(&phy_lock, flags); + +err0: + 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)) { + pr_err("unable to find transceiver\n"); + 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; + } + + 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; + } + + 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 __init 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) { + pr_err("phy_bind(): No memory for 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); |