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 00000000000..a9984c700d2 --- /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 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);  |