[mirror_ubuntu-bionic-kernel.git] / drivers / usb / gadget / udc / udc-core.c

/**
 * udc.c - Core UDC Framework
 *
 * Copyright (C) 2010 Texas Instruments
 * Author: Felipe Balbi <balbi@ti.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2  of
 * the License as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/list.h>
#include <linux/err.h>
#include <linux/dma-mapping.h>
#include <linux/workqueue.h>

#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
#include <linux/usb.h>

/**
 * struct usb_udc - describes one usb device controller
 * @driver - the gadget driver pointer. For use by the class code
 * @dev - the child device to the actual controller
 * @gadget - the gadget. For use by the class code
 * @list - for use by the udc class driver
 *
 * This represents the internal data structure which is used by the UDC-class
 * to hold information about udc driver and gadget together.
 */
struct usb_udc {
	struct usb_gadget_driver	*driver;
	struct usb_gadget		*gadget;
	struct device			dev;
	struct list_head		list;
};

static struct class *udc_class;
static LIST_HEAD(udc_list);
static DEFINE_MUTEX(udc_lock);

/* ------------------------------------------------------------------------- */

#ifdef	CONFIG_HAS_DMA

int usb_gadget_map_request(struct usb_gadget *gadget,
		struct usb_request *req, int is_in)
{
	if (req->length == 0)
		return 0;

	if (req->num_sgs) {
		int     mapped;

		mapped = dma_map_sg(&gadget->dev, req->sg, req->num_sgs,
				is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
		if (mapped == 0) {
			dev_err(&gadget->dev, "failed to map SGs\n");
			return -EFAULT;
		}

		req->num_mapped_sgs = mapped;
	} else {
		req->dma = dma_map_single(&gadget->dev, req->buf, req->length,
				is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);

		if (dma_mapping_error(&gadget->dev, req->dma)) {
			dev_err(&gadget->dev, "failed to map buffer\n");
			return -EFAULT;
		}
	}

	return 0;
}
EXPORT_SYMBOL_GPL(usb_gadget_map_request);

void usb_gadget_unmap_request(struct usb_gadget *gadget,
		struct usb_request *req, int is_in)
{
	if (req->length == 0)
		return;

	if (req->num_mapped_sgs) {
		dma_unmap_sg(&gadget->dev, req->sg, req->num_mapped_sgs,
				is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);

		req->num_mapped_sgs = 0;
	} else {
		dma_unmap_single(&gadget->dev, req->dma, req->length,
				is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
	}
}
EXPORT_SYMBOL_GPL(usb_gadget_unmap_request);

#endif	/* CONFIG_HAS_DMA */

/* ------------------------------------------------------------------------- */

/**
 * usb_gadget_giveback_request - give the request back to the gadget layer
 * Context: in_interrupt()
 *
 * This is called by device controller drivers in order to return the
 * completed request back to the gadget layer.
 */
void usb_gadget_giveback_request(struct usb_ep *ep,
		struct usb_request *req)
{
	if (likely(req->status == 0))
		usb_led_activity(USB_LED_EVENT_GADGET);

	req->complete(ep, req);
}
EXPORT_SYMBOL_GPL(usb_gadget_giveback_request);

/* ------------------------------------------------------------------------- */

static void usb_gadget_state_work(struct work_struct *work)
{
	struct usb_gadget	*gadget = work_to_gadget(work);
	struct usb_udc		*udc = NULL;

	mutex_lock(&udc_lock);
	list_for_each_entry(udc, &udc_list, list)
		if (udc->gadget == gadget)
			goto found;
	mutex_unlock(&udc_lock);

	return;

found:
	mutex_unlock(&udc_lock);

	sysfs_notify(&udc->dev.kobj, NULL, "state");
}

void usb_gadget_set_state(struct usb_gadget *gadget,
		enum usb_device_state state)
{
	gadget->state = state;
	schedule_work(&gadget->work);
}
EXPORT_SYMBOL_GPL(usb_gadget_set_state);

/* ------------------------------------------------------------------------- */

/**
 * usb_gadget_udc_reset - notifies the udc core that bus reset occurs
 * @gadget: The gadget which bus reset occurs
 * @driver: The gadget driver we want to notify
 *
 * If the udc driver has bus reset handler, it needs to call this when the bus
 * reset occurs, it notifies the gadget driver that the bus reset occurs as
 * well as updates gadget state.
 */
void usb_gadget_udc_reset(struct usb_gadget *gadget,
		struct usb_gadget_driver *driver)
{
	driver->reset(gadget);
	usb_gadget_set_state(gadget, USB_STATE_DEFAULT);
}
EXPORT_SYMBOL_GPL(usb_gadget_udc_reset);

/**
 * usb_gadget_udc_start - tells usb device controller to start up
 * @gadget: The gadget we want to get started
 * @driver: The driver we want to bind to @gadget
 *
 * This call is issued by the UDC Class driver when it's about
 * to register a gadget driver to the device controller, before
 * calling gadget driver's bind() method.
 *
 * It allows the controller to be powered off until strictly
 * necessary to have it powered on.
 *
 * Returns zero on success, else negative errno.
 */
static inline int usb_gadget_udc_start(struct usb_gadget *gadget,
		struct usb_gadget_driver *driver)
{
	return gadget->ops->udc_start(gadget, driver);
}

/**
 * usb_gadget_udc_stop - tells usb device controller we don't need it anymore
 * @gadget: The device we want to stop activity
 * @driver: The driver to unbind from @gadget
 *
 * This call is issued by the UDC Class driver after calling
 * gadget driver's unbind() method.
 *
 * The details are implementation specific, but it can go as
 * far as powering off UDC completely and disable its data
 * line pullups.
 */
static inline void usb_gadget_udc_stop(struct usb_gadget *gadget,
		struct usb_gadget_driver *driver)
{
	gadget->ops->udc_stop(gadget, driver);
}

/**
 * usb_udc_release - release the usb_udc struct
 * @dev: the dev member within usb_udc
 *
 * This is called by driver's core in order to free memory once the last
 * reference is released.
 */
static void usb_udc_release(struct device *dev)
{
	struct usb_udc *udc;

	udc = container_of(dev, struct usb_udc, dev);
	dev_dbg(dev, "releasing '%s'\n", dev_name(dev));
	kfree(udc);
}

static const struct attribute_group *usb_udc_attr_groups[];

static void usb_udc_nop_release(struct device *dev)
{
	dev_vdbg(dev, "%s\n", __func__);
}

/**
 * usb_add_gadget_udc_release - adds a new gadget to the udc class driver list
 * @parent: the parent device to this udc. Usually the controller driver's
 * device.
 * @gadget: the gadget to be added to the list.
 * @release: a gadget release function.
 *
 * Returns zero on success, negative errno otherwise.
 */
int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
		void (*release)(struct device *dev))
{
	struct usb_udc		*udc;
	int			ret = -ENOMEM;

	udc = kzalloc(sizeof(*udc), GFP_KERNEL);
	if (!udc)
		goto err1;

	dev_set_name(&gadget->dev, "gadget");
	INIT_WORK(&gadget->work, usb_gadget_state_work);
	gadget->dev.parent = parent;

#ifdef	CONFIG_HAS_DMA
	dma_set_coherent_mask(&gadget->dev, parent->coherent_dma_mask);
	gadget->dev.dma_parms = parent->dma_parms;
	gadget->dev.dma_mask = parent->dma_mask;
#endif

	if (release)
		gadget->dev.release = release;
	else
		gadget->dev.release = usb_udc_nop_release;

	ret = device_register(&gadget->dev);
	if (ret)
		goto err2;

	device_initialize(&udc->dev);
	udc->dev.release = usb_udc_release;
	udc->dev.class = udc_class;
	udc->dev.groups = usb_udc_attr_groups;
	udc->dev.parent = parent;
	ret = dev_set_name(&udc->dev, "%s", kobject_name(&parent->kobj));
	if (ret)
		goto err3;

	udc->gadget = gadget;

	mutex_lock(&udc_lock);
	list_add_tail(&udc->list, &udc_list);

	ret = device_add(&udc->dev);
	if (ret)
		goto err4;

	usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED);

	mutex_unlock(&udc_lock);

	return 0;

err4:
	list_del(&udc->list);
	mutex_unlock(&udc_lock);

err3:
	put_device(&udc->dev);

err2:
	put_device(&gadget->dev);
	kfree(udc);

err1:
	return ret;
}
EXPORT_SYMBOL_GPL(usb_add_gadget_udc_release);

/**
 * usb_add_gadget_udc - adds a new gadget to the udc class driver list
 * @parent: the parent device to this udc. Usually the controller
 * driver's device.
 * @gadget: the gadget to be added to the list
 *
 * Returns zero on success, negative errno otherwise.
 */
int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget)
{
	return usb_add_gadget_udc_release(parent, gadget, NULL);
}
EXPORT_SYMBOL_GPL(usb_add_gadget_udc);

static void usb_gadget_remove_driver(struct usb_udc *udc)
{
	dev_dbg(&udc->dev, "unregistering UDC driver [%s]\n",
			udc->gadget->name);

	kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);

	usb_gadget_disconnect(udc->gadget);
	udc->driver->disconnect(udc->gadget);
	udc->driver->unbind(udc->gadget);
	usb_gadget_udc_stop(udc->gadget, NULL);

	udc->driver = NULL;
	udc->dev.driver = NULL;
	udc->gadget->dev.driver = NULL;
}

/**
 * usb_del_gadget_udc - deletes @udc from udc_list
 * @gadget: the gadget to be removed.
 *
 * This, will call usb_gadget_unregister_driver() if
 * the @udc is still busy.
 */
void usb_del_gadget_udc(struct usb_gadget *gadget)
{
	struct usb_udc		*udc = NULL;

	mutex_lock(&udc_lock);
	list_for_each_entry(udc, &udc_list, list)
		if (udc->gadget == gadget)
			goto found;

	dev_err(gadget->dev.parent, "gadget not registered.\n");
	mutex_unlock(&udc_lock);

	return;

found:
	dev_vdbg(gadget->dev.parent, "unregistering gadget\n");

	list_del(&udc->list);
	mutex_unlock(&udc_lock);

	if (udc->driver)
		usb_gadget_remove_driver(udc);

	kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE);
	flush_work(&gadget->work);
	device_unregister(&udc->dev);
	device_unregister(&gadget->dev);
}
EXPORT_SYMBOL_GPL(usb_del_gadget_udc);

/* ------------------------------------------------------------------------- */

static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *driver)
{
	int ret;

	dev_dbg(&udc->dev, "registering UDC driver [%s]\n",
			driver->function);

	udc->driver = driver;
	udc->dev.driver = &driver->driver;
	udc->gadget->dev.driver = &driver->driver;

	ret = driver->bind(udc->gadget, driver);
	if (ret)
		goto err1;
	ret = usb_gadget_udc_start(udc->gadget, driver);
	if (ret) {
		driver->unbind(udc->gadget);
		goto err1;
	}
	usb_gadget_connect(udc->gadget);

	kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
	return 0;
err1:
	if (ret != -EISNAM)
		dev_err(&udc->dev, "failed to start %s: %d\n",
			udc->driver->function, ret);
	udc->driver = NULL;
	udc->dev.driver = NULL;
	udc->gadget->dev.driver = NULL;
	return ret;
}

int udc_attach_driver(const char *name, struct usb_gadget_driver *driver)
{
	struct usb_udc *udc = NULL;
	int ret = -ENODEV;

	mutex_lock(&udc_lock);
	list_for_each_entry(udc, &udc_list, list) {
		ret = strcmp(name, dev_name(&udc->dev));
		if (!ret)
			break;
	}
	if (ret) {
		ret = -ENODEV;
		goto out;
	}
	if (udc->driver) {
		ret = -EBUSY;
		goto out;
	}
	ret = udc_bind_to_driver(udc, driver);
out:
	mutex_unlock(&udc_lock);
	return ret;
}
EXPORT_SYMBOL_GPL(udc_attach_driver);

int usb_gadget_probe_driver(struct usb_gadget_driver *driver)
{
	struct usb_udc		*udc = NULL;
	int			ret;

	if (!driver || !driver->bind || !driver->setup)
		return -EINVAL;

	mutex_lock(&udc_lock);
	list_for_each_entry(udc, &udc_list, list) {
		/* For now we take the first one */
		if (!udc->driver)
			goto found;
	}

	pr_debug("couldn't find an available UDC\n");
	mutex_unlock(&udc_lock);
	return -ENODEV;
found:
	ret = udc_bind_to_driver(udc, driver);
	mutex_unlock(&udc_lock);
	return ret;
}
EXPORT_SYMBOL_GPL(usb_gadget_probe_driver);

int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
{
	struct usb_udc		*udc = NULL;
	int			ret = -ENODEV;

	if (!driver || !driver->unbind)
		return -EINVAL;

	mutex_lock(&udc_lock);
	list_for_each_entry(udc, &udc_list, list)
		if (udc->driver == driver) {
			usb_gadget_remove_driver(udc);
			usb_gadget_set_state(udc->gadget,
					USB_STATE_NOTATTACHED);
			ret = 0;
			break;
		}

	mutex_unlock(&udc_lock);
	return ret;
}
EXPORT_SYMBOL_GPL(usb_gadget_unregister_driver);

/* ------------------------------------------------------------------------- */

static ssize_t usb_udc_srp_store(struct device *dev,
		struct device_attribute *attr, const char *buf, size_t n)
{
	struct usb_udc		*udc = container_of(dev, struct usb_udc, dev);

	if (sysfs_streq(buf, "1"))
		usb_gadget_wakeup(udc->gadget);

	return n;
}
static DEVICE_ATTR(srp, S_IWUSR, NULL, usb_udc_srp_store);

static ssize_t usb_udc_softconn_store(struct device *dev,
		struct device_attribute *attr, const char *buf, size_t n)
{
	struct usb_udc		*udc = container_of(dev, struct usb_udc, dev);

	if (!udc->driver) {
		dev_err(dev, "soft-connect without a gadget driver\n");
		return -EOPNOTSUPP;
	}

	if (sysfs_streq(buf, "connect")) {
		usb_gadget_udc_start(udc->gadget, udc->driver);
		usb_gadget_connect(udc->gadget);
	} else if (sysfs_streq(buf, "disconnect")) {
		usb_gadget_disconnect(udc->gadget);
		usb_gadget_udc_stop(udc->gadget, udc->driver);
	} else {
		dev_err(dev, "unsupported command '%s'\n", buf);
		return -EINVAL;
	}

	return n;
}
static DEVICE_ATTR(soft_connect, S_IWUSR, NULL, usb_udc_softconn_store);

static ssize_t state_show(struct device *dev, struct device_attribute *attr,
			  char *buf)
{
	struct usb_udc		*udc = container_of(dev, struct usb_udc, dev);
	struct usb_gadget	*gadget = udc->gadget;

	return sprintf(buf, "%s\n", usb_state_string(gadget->state));
}
static DEVICE_ATTR_RO(state);

#define USB_UDC_SPEED_ATTR(name, param)					\
ssize_t name##_show(struct device *dev,					\
		struct device_attribute *attr, char *buf)		\
{									\
	struct usb_udc *udc = container_of(dev, struct usb_udc, dev);	\
	return snprintf(buf, PAGE_SIZE, "%s\n",				\
			usb_speed_string(udc->gadget->param));		\
}									\
static DEVICE_ATTR_RO(name)

static USB_UDC_SPEED_ATTR(current_speed, speed);
static USB_UDC_SPEED_ATTR(maximum_speed, max_speed);

#define USB_UDC_ATTR(name)					\
ssize_t name##_show(struct device *dev,				\
		struct device_attribute *attr, char *buf)	\
{								\
	struct usb_udc		*udc = container_of(dev, struct usb_udc, dev); \
	struct usb_gadget	*gadget = udc->gadget;		\
								\
	return snprintf(buf, PAGE_SIZE, "%d\n", gadget->name);	\
}								\
static DEVICE_ATTR_RO(name)

static USB_UDC_ATTR(is_otg);
static USB_UDC_ATTR(is_a_peripheral);
static USB_UDC_ATTR(b_hnp_enable);
static USB_UDC_ATTR(a_hnp_support);
static USB_UDC_ATTR(a_alt_hnp_support);

static struct attribute *usb_udc_attrs[] = {
	&dev_attr_srp.attr,
	&dev_attr_soft_connect.attr,
	&dev_attr_state.attr,
	&dev_attr_current_speed.attr,
	&dev_attr_maximum_speed.attr,

	&dev_attr_is_otg.attr,
	&dev_attr_is_a_peripheral.attr,
	&dev_attr_b_hnp_enable.attr,
	&dev_attr_a_hnp_support.attr,
	&dev_attr_a_alt_hnp_support.attr,
	NULL,
};

static const struct attribute_group usb_udc_attr_group = {
	.attrs = usb_udc_attrs,
};

static const struct attribute_group *usb_udc_attr_groups[] = {
	&usb_udc_attr_group,
	NULL,
};

static int usb_udc_uevent(struct device *dev, struct kobj_uevent_env *env)
{
	struct usb_udc		*udc = container_of(dev, struct usb_udc, dev);
	int			ret;

	ret = add_uevent_var(env, "USB_UDC_NAME=%s", udc->gadget->name);
	if (ret) {
		dev_err(dev, "failed to add uevent USB_UDC_NAME\n");
		return ret;
	}

	if (udc->driver) {
		ret = add_uevent_var(env, "USB_UDC_DRIVER=%s",
				udc->driver->function);
		if (ret) {
			dev_err(dev, "failed to add uevent USB_UDC_DRIVER\n");
			return ret;
		}
	}

	return 0;
}

static int __init usb_udc_init(void)
{
	udc_class = class_create(THIS_MODULE, "udc");
	if (IS_ERR(udc_class)) {
		pr_err("failed to create udc class --> %ld\n",
				PTR_ERR(udc_class));
		return PTR_ERR(udc_class);
	}

	udc_class->dev_uevent = usb_udc_uevent;
	return 0;
}
subsys_initcall(usb_udc_init);

static void __exit usb_udc_exit(void)
{
	class_destroy(udc_class);
}
module_exit(usb_udc_exit);

MODULE_DESCRIPTION("UDC Framework");
MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
2ccea03a FB	1	/**
	2	* udc.c - Core UDC Framework
	3	*
	4	* Copyright (C) 2010 Texas Instruments
	5	* Author: Felipe Balbi <balbi@ti.com>
	6	*
	7	* This program is free software: you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License version 2 of
	9	* the License as published by the Free Software Foundation.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program. If not, see <http://www.gnu.org/licenses/>.
	18	*/
	19
	20	#include <linux/kernel.h>
	21	#include <linux/module.h>
	22	#include <linux/device.h>
	23	#include <linux/list.h>
	24	#include <linux/err.h>
a698908d	25	#include <linux/dma-mapping.h>
5702f753	26	#include <linux/workqueue.h>
2ccea03a FB	27
	28	#include <linux/usb/ch9.h>
	29	#include <linux/usb/gadget.h>
0cfbd328	30	#include <linux/usb.h>
2ccea03a FB	31
	32	/**
	33	* struct usb_udc - describes one usb device controller
	34	* @driver - the gadget driver pointer. For use by the class code
	35	* @dev - the child device to the actual controller
	36	* @gadget - the gadget. For use by the class code
	37	* @list - for use by the udc class driver
	38	*
	39	* This represents the internal data structure which is used by the UDC-class
	40	* to hold information about udc driver and gadget together.
	41	*/
	42	struct usb_udc {
	43	struct usb_gadget_driver *driver;
	44	struct usb_gadget *gadget;
	45	struct device dev;
	46	struct list_head list;
	47	};
	48
	49	static struct class *udc_class;
2ccea03a FB	50	static LIST_HEAD(udc_list);
	51	static DEFINE_MUTEX(udc_lock);
	52
	53	/* ------------------------------------------------------------------------- */
	54
908b9613 AS	55	#ifdef CONFIG_HAS_DMA
908b9613 AS	56
a698908d FB	57	int usb_gadget_map_request(struct usb_gadget *gadget,
	58	struct usb_request *req, int is_in)
	59	{
	60	if (req->length == 0)
	61	return 0;
	62
	63	if (req->num_sgs) {
	64	int mapped;
	65
	66	mapped = dma_map_sg(&gadget->dev, req->sg, req->num_sgs,
	67	is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
	68	if (mapped == 0) {
	69	dev_err(&gadget->dev, "failed to map SGs\n");
	70	return -EFAULT;
	71	}
	72
	73	req->num_mapped_sgs = mapped;
	74	} else {
	75	req->dma = dma_map_single(&gadget->dev, req->buf, req->length,
	76	is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
	77
	78	if (dma_mapping_error(&gadget->dev, req->dma)) {
	79	dev_err(&gadget->dev, "failed to map buffer\n");
	80	return -EFAULT;
	81	}
	82	}
	83
	84	return 0;
	85	}
	86	EXPORT_SYMBOL_GPL(usb_gadget_map_request);
	87
	88	void usb_gadget_unmap_request(struct usb_gadget *gadget,
	89	struct usb_request *req, int is_in)
	90	{
	91	if (req->length == 0)
	92	return;
	93
	94	if (req->num_mapped_sgs) {
	95	dma_unmap_sg(&gadget->dev, req->sg, req->num_mapped_sgs,
	96	is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
	97
	98	req->num_mapped_sgs = 0;
	99	} else {
	100	dma_unmap_single(&gadget->dev, req->dma, req->length,
	101	is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
	102	}
	103	}
	104	EXPORT_SYMBOL_GPL(usb_gadget_unmap_request);
	105
908b9613 AS	106	#endif /* CONFIG_HAS_DMA */
908b9613 AS	107
a698908d FB	108	/* ------------------------------------------------------------------------- */
a698908d FB	109
3fc2aa55 MS	110	/**
	111	* usb_gadget_giveback_request - give the request back to the gadget layer
	112	* Context: in_interrupt()
	113	*
	114	* This is called by device controller drivers in order to return the
	115	* completed request back to the gadget layer.
	116	*/
	117	void usb_gadget_giveback_request(struct usb_ep *ep,
	118	struct usb_request *req)
	119	{
0cfbd328 MS	120	if (likely(req->status == 0))
	121	usb_led_activity(USB_LED_EVENT_GADGET);
	122
3fc2aa55 MS	123	req->complete(ep, req);
	124	}
	125	EXPORT_SYMBOL_GPL(usb_gadget_giveback_request);
	126
	127	/* ------------------------------------------------------------------------- */
	128
5702f753 FB	129	static void usb_gadget_state_work(struct work_struct *work)
	130	{
	131	struct usb_gadget *gadget = work_to_gadget(work);
af54954a	132	struct usb_udc *udc = NULL;
5702f753	133
af54954a AL	134	mutex_lock(&udc_lock);
	135	list_for_each_entry(udc, &udc_list, list)
	136	if (udc->gadget == gadget)
	137	goto found;
	138	mutex_unlock(&udc_lock);
	139
	140	return;
	141
	142	found:
	143	mutex_unlock(&udc_lock);
	144
	145	sysfs_notify(&udc->dev.kobj, NULL, "state");
5702f753 FB	146	}
5702f753 FB	147
49401f41 FB	148	void usb_gadget_set_state(struct usb_gadget *gadget,
	149	enum usb_device_state state)
	150	{
	151	gadget->state = state;
5702f753	152	schedule_work(&gadget->work);
49401f41 FB	153	}
	154	EXPORT_SYMBOL_GPL(usb_gadget_set_state);
	155
	156	/* ------------------------------------------------------------------------- */
	157
974a70bd PC	158	/**
	159	* usb_gadget_udc_reset - notifies the udc core that bus reset occurs
	160	* @gadget: The gadget which bus reset occurs
	161	* @driver: The gadget driver we want to notify
	162	*
	163	* If the udc driver has bus reset handler, it needs to call this when the bus
	164	* reset occurs, it notifies the gadget driver that the bus reset occurs as
	165	* well as updates gadget state.
	166	*/
	167	void usb_gadget_udc_reset(struct usb_gadget *gadget,
	168	struct usb_gadget_driver *driver)
	169	{
	170	driver->reset(gadget);
	171	usb_gadget_set_state(gadget, USB_STATE_DEFAULT);
	172	}
	173	EXPORT_SYMBOL_GPL(usb_gadget_udc_reset);
	174
352c2dc8 SAS	175	/**
	176	* usb_gadget_udc_start - tells usb device controller to start up
	177	* @gadget: The gadget we want to get started
	178	* @driver: The driver we want to bind to @gadget
	179	*
	180	* This call is issued by the UDC Class driver when it's about
	181	* to register a gadget driver to the device controller, before
	182	* calling gadget driver's bind() method.
	183	*
	184	* It allows the controller to be powered off until strictly
	185	* necessary to have it powered on.
	186	*
	187	* Returns zero on success, else negative errno.
	188	*/
	189	static inline int usb_gadget_udc_start(struct usb_gadget *gadget,
	190	struct usb_gadget_driver *driver)
	191	{
	192	return gadget->ops->udc_start(gadget, driver);
	193	}
	194
352c2dc8 SAS	195	/**
	196	* usb_gadget_udc_stop - tells usb device controller we don't need it anymore
	197	* @gadget: The device we want to stop activity
	198	* @driver: The driver to unbind from @gadget
	199	*
	200	* This call is issued by the UDC Class driver after calling
	201	* gadget driver's unbind() method.
	202	*
	203	* The details are implementation specific, but it can go as
	204	* far as powering off UDC completely and disable its data
	205	* line pullups.
	206	*/
	207	static inline void usb_gadget_udc_stop(struct usb_gadget *gadget,
	208	struct usb_gadget_driver *driver)
	209	{
	210	gadget->ops->udc_stop(gadget, driver);
	211	}
	212
2ccea03a FB	213	/**
	214	* usb_udc_release - release the usb_udc struct
	215	* @dev: the dev member within usb_udc
	216	*
	217	* This is called by driver's core in order to free memory once the last
	218	* reference is released.
	219	*/
	220	static void usb_udc_release(struct device *dev)
	221	{
	222	struct usb_udc *udc;
	223
	224	udc = container_of(dev, struct usb_udc, dev);
	225	dev_dbg(dev, "releasing '%s'\n", dev_name(dev));
	226	kfree(udc);
	227	}
	228
019f976e	229	static const struct attribute_group *usb_udc_attr_groups[];
792bfcf7 FB	230
	231	static void usb_udc_nop_release(struct device *dev)
	232	{
	233	dev_vdbg(dev, "%s\n", __func__);
	234	}
	235
2ccea03a	236	/**
792bfcf7 FB	237	* usb_add_gadget_udc_release - adds a new gadget to the udc class driver list
	238	* @parent: the parent device to this udc. Usually the controller driver's
	239	* device.
	240	* @gadget: the gadget to be added to the list.
	241	* @release: a gadget release function.
2ccea03a FB	242	*
	243	* Returns zero on success, negative errno otherwise.
	244	*/
792bfcf7 FB	245	int usb_add_gadget_udc_release(struct device parent, struct usb_gadget gadget,
792bfcf7 FB	246	void (release)(struct device dev))
2ccea03a FB	247	{
	248	struct usb_udc *udc;
	249	int ret = -ENOMEM;
	250
	251	udc = kzalloc(sizeof(*udc), GFP_KERNEL);
	252	if (!udc)
	253	goto err1;
	254
7bce401c	255	dev_set_name(&gadget->dev, "gadget");
5702f753	256	INIT_WORK(&gadget->work, usb_gadget_state_work);
2ed14320	257	gadget->dev.parent = parent;
f07bd56b	258
908b9613	259	#ifdef CONFIG_HAS_DMA
658c8cf1 FB	260	dma_set_coherent_mask(&gadget->dev, parent->coherent_dma_mask);
	261	gadget->dev.dma_parms = parent->dma_parms;
	262	gadget->dev.dma_mask = parent->dma_mask;
908b9613	263	#endif
658c8cf1	264
ddf47ccb	265	if (release)
792bfcf7	266	gadget->dev.release = release;
ddf47ccb FB	267	else
ddf47ccb FB	268	gadget->dev.release = usb_udc_nop_release;
792bfcf7	269
7bce401c FB	270	ret = device_register(&gadget->dev);
	271	if (ret)
	272	goto err2;
f07bd56b	273
2ccea03a FB	274	device_initialize(&udc->dev);
	275	udc->dev.release = usb_udc_release;
	276	udc->dev.class = udc_class;
019f976e	277	udc->dev.groups = usb_udc_attr_groups;
2ccea03a FB	278	udc->dev.parent = parent;
	279	ret = dev_set_name(&udc->dev, "%s", kobject_name(&parent->kobj));
	280	if (ret)
f07bd56b	281	goto err3;
2ccea03a FB	282
	283	udc->gadget = gadget;
	284
	285	mutex_lock(&udc_lock);
	286	list_add_tail(&udc->list, &udc_list);
	287
	288	ret = device_add(&udc->dev);
	289	if (ret)
f07bd56b	290	goto err4;
2ccea03a	291
49401f41	292	usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED);
2ccea03a FB	293
	294	mutex_unlock(&udc_lock);
	295
	296	return 0;
f07bd56b FB	297
f07bd56b FB	298	err4:
2ccea03a FB	299	list_del(&udc->list);
	300	mutex_unlock(&udc_lock);
	301
f07bd56b	302	err3:
2ccea03a FB	303	put_device(&udc->dev);
2ccea03a FB	304
f07bd56b	305	err2:
7bce401c	306	put_device(&gadget->dev);
c5dbc220	307	kfree(udc);
7bce401c	308
2ccea03a FB	309	err1:
	310	return ret;
	311	}
792bfcf7 FB	312	EXPORT_SYMBOL_GPL(usb_add_gadget_udc_release);
	313
	314	/**
	315	* usb_add_gadget_udc - adds a new gadget to the udc class driver list
	316	* @parent: the parent device to this udc. Usually the controller
	317	* driver's device.
	318	* @gadget: the gadget to be added to the list
	319	*
	320	* Returns zero on success, negative errno otherwise.
	321	*/
	322	int usb_add_gadget_udc(struct device parent, struct usb_gadget gadget)
	323	{
	324	return usb_add_gadget_udc_release(parent, gadget, NULL);
	325	}
2ccea03a FB	326	EXPORT_SYMBOL_GPL(usb_add_gadget_udc);
	327
	328	static void usb_gadget_remove_driver(struct usb_udc *udc)
	329	{
	330	dev_dbg(&udc->dev, "unregistering UDC driver [%s]\n",
	331	udc->gadget->name);
	332
	333	kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
	334
2d7ebbb0 FB	335	usb_gadget_disconnect(udc->gadget);
	336	udc->driver->disconnect(udc->gadget);
	337	udc->driver->unbind(udc->gadget);
511f3c53	338	usb_gadget_udc_stop(udc->gadget, NULL);
2ccea03a FB	339
	340	udc->driver = NULL;
	341	udc->dev.driver = NULL;
70d3a498	342	udc->gadget->dev.driver = NULL;
2ccea03a FB	343	}
	344
	345	/**
	346	* usb_del_gadget_udc - deletes @udc from udc_list
	347	* @gadget: the gadget to be removed.
	348	*
	349	* This, will call usb_gadget_unregister_driver() if
	350	* the @udc is still busy.
	351	*/
	352	void usb_del_gadget_udc(struct usb_gadget *gadget)
	353	{
	354	struct usb_udc *udc = NULL;
	355
	356	mutex_lock(&udc_lock);
	357	list_for_each_entry(udc, &udc_list, list)
	358	if (udc->gadget == gadget)
	359	goto found;
	360
	361	dev_err(gadget->dev.parent, "gadget not registered.\n");
	362	mutex_unlock(&udc_lock);
	363
	364	return;
	365
	366	found:
	367	dev_vdbg(gadget->dev.parent, "unregistering gadget\n");
	368
	369	list_del(&udc->list);
	370	mutex_unlock(&udc_lock);
	371
	372	if (udc->driver)
	373	usb_gadget_remove_driver(udc);
	374
	375	kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE);
5702f753	376	flush_work(&gadget->work);
2ccea03a	377	device_unregister(&udc->dev);
7bce401c	378	device_unregister(&gadget->dev);
2ccea03a FB	379	}
	380	EXPORT_SYMBOL_GPL(usb_del_gadget_udc);
	381
	382	/* ------------------------------------------------------------------------- */
	383
4c49a5f0	384	static int udc_bind_to_driver(struct usb_udc udc, struct usb_gadget_driver driver)
2ccea03a	385	{
4c49a5f0	386	int ret;
2ccea03a	387
2ccea03a FB	388	dev_dbg(&udc->dev, "registering UDC driver [%s]\n",
	389	driver->function);
	390
	391	udc->driver = driver;
	392	udc->dev.driver = &driver->driver;
70d3a498	393	udc->gadget->dev.driver = &driver->driver;
2ccea03a	394
2d7ebbb0 FB	395	ret = driver->bind(udc->gadget, driver);
	396	if (ret)
	397	goto err1;
	398	ret = usb_gadget_udc_start(udc->gadget, driver);
	399	if (ret) {
	400	driver->unbind(udc->gadget);
	401	goto err1;
352c2dc8	402	}
2d7ebbb0	403	usb_gadget_connect(udc->gadget);
2ccea03a FB	404
2ccea03a FB	405	kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
2ccea03a	406	return 0;
2ccea03a	407	err1:
f8cffc84 FE	408	if (ret != -EISNAM)
f8cffc84 FE	409	dev_err(&udc->dev, "failed to start %s: %d\n",
2ccea03a FB	410	udc->driver->function, ret);
	411	udc->driver = NULL;
	412	udc->dev.driver = NULL;
70d3a498	413	udc->gadget->dev.driver = NULL;
4c49a5f0 SAS	414	return ret;
	415	}
	416
	417	int udc_attach_driver(const char name, struct usb_gadget_driver driver)
	418	{
	419	struct usb_udc *udc = NULL;
	420	int ret = -ENODEV;
	421
	422	mutex_lock(&udc_lock);
	423	list_for_each_entry(udc, &udc_list, list) {
	424	ret = strcmp(name, dev_name(&udc->dev));
	425	if (!ret)
	426	break;
	427	}
	428	if (ret) {
	429	ret = -ENODEV;
	430	goto out;
	431	}
	432	if (udc->driver) {
	433	ret = -EBUSY;
	434	goto out;
	435	}
	436	ret = udc_bind_to_driver(udc, driver);
	437	out:
	438	mutex_unlock(&udc_lock);
	439	return ret;
	440	}
	441	EXPORT_SYMBOL_GPL(udc_attach_driver);
	442
	443	int usb_gadget_probe_driver(struct usb_gadget_driver *driver)
	444	{
	445	struct usb_udc *udc = NULL;
	446	int ret;
	447
	448	if (!driver \|\| !driver->bind \|\| !driver->setup)
	449	return -EINVAL;
	450
	451	mutex_lock(&udc_lock);
	452	list_for_each_entry(udc, &udc_list, list) {
	453	/* For now we take the first one */
	454	if (!udc->driver)
	455	goto found;
	456	}
	457
	458	pr_debug("couldn't find an available UDC\n");
	459	mutex_unlock(&udc_lock);
	460	return -ENODEV;
	461	found:
	462	ret = udc_bind_to_driver(udc, driver);
2ccea03a FB	463	mutex_unlock(&udc_lock);
	464	return ret;
	465	}
	466	EXPORT_SYMBOL_GPL(usb_gadget_probe_driver);
	467
	468	int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
	469	{
	470	struct usb_udc *udc = NULL;
	471	int ret = -ENODEV;
	472
	473	if (!driver \|\| !driver->unbind)
	474	return -EINVAL;
	475
	476	mutex_lock(&udc_lock);
	477	list_for_each_entry(udc, &udc_list, list)
	478	if (udc->driver == driver) {
	479	usb_gadget_remove_driver(udc);
b5fb8d0a PC	480	usb_gadget_set_state(udc->gadget,
b5fb8d0a PC	481	USB_STATE_NOTATTACHED);
2ccea03a FB	482	ret = 0;
	483	break;
	484	}
	485
	486	mutex_unlock(&udc_lock);
	487	return ret;
	488	}
	489	EXPORT_SYMBOL_GPL(usb_gadget_unregister_driver);
	490
	491	/* ------------------------------------------------------------------------- */
	492
	493	static ssize_t usb_udc_srp_store(struct device *dev,
	494	struct device_attribute attr, const char buf, size_t n)
	495	{
1d91a962	496	struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
2ccea03a FB	497
	498	if (sysfs_streq(buf, "1"))
	499	usb_gadget_wakeup(udc->gadget);
	500
	501	return n;
	502	}
	503	static DEVICE_ATTR(srp, S_IWUSR, NULL, usb_udc_srp_store);
	504
	505	static ssize_t usb_udc_softconn_store(struct device *dev,
	506	struct device_attribute attr, const char buf, size_t n)
	507	{
865569ba	508	struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
2ccea03a	509
bfa6b18c FB	510	if (!udc->driver) {
	511	dev_err(dev, "soft-connect without a gadget driver\n");
	512	return -EOPNOTSUPP;
	513	}
	514
2ccea03a	515	if (sysfs_streq(buf, "connect")) {
2d7ebbb0	516	usb_gadget_udc_start(udc->gadget, udc->driver);
2ccea03a FB	517	usb_gadget_connect(udc->gadget);
2ccea03a FB	518	} else if (sysfs_streq(buf, "disconnect")) {
83a787a7	519	usb_gadget_disconnect(udc->gadget);
2d7ebbb0	520	usb_gadget_udc_stop(udc->gadget, udc->driver);
2ccea03a FB	521	} else {
	522	dev_err(dev, "unsupported command '%s'\n", buf);
	523	return -EINVAL;
	524	}
	525
	526	return n;
	527	}
	528	static DEVICE_ATTR(soft_connect, S_IWUSR, NULL, usb_udc_softconn_store);
	529
ce26bd23 GKH	530	static ssize_t state_show(struct device dev, struct device_attribute attr,
ce26bd23 GKH	531	char *buf)
49401f41 FB	532	{
	533	struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
	534	struct usb_gadget *gadget = udc->gadget;
	535
	536	return sprintf(buf, "%s\n", usb_state_string(gadget->state));
	537	}
ce26bd23	538	static DEVICE_ATTR_RO(state);
49401f41	539
d327ab5b	540	#define USB_UDC_SPEED_ATTR(name, param) \
ce26bd23	541	ssize_t name##_show(struct device *dev, \
d327ab5b MN	542	struct device_attribute attr, char buf) \
	543	{ \
	544	struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
	545	return snprintf(buf, PAGE_SIZE, "%s\n", \
	546	usb_speed_string(udc->gadget->param)); \
	547	} \
ce26bd23	548	static DEVICE_ATTR_RO(name)
d327ab5b MN	549
	550	static USB_UDC_SPEED_ATTR(current_speed, speed);
	551	static USB_UDC_SPEED_ATTR(maximum_speed, max_speed);
	552
2ccea03a	553	#define USB_UDC_ATTR(name) \
ce26bd23	554	ssize_t name##_show(struct device *dev, \
2ccea03a FB	555	struct device_attribute attr, char buf) \
2ccea03a FB	556	{ \
019f976e	557	struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
2ccea03a FB	558	struct usb_gadget *gadget = udc->gadget; \
	559	\
	560	return snprintf(buf, PAGE_SIZE, "%d\n", gadget->name); \
	561	} \
ce26bd23	562	static DEVICE_ATTR_RO(name)
2ccea03a	563
2ccea03a FB	564	static USB_UDC_ATTR(is_otg);
	565	static USB_UDC_ATTR(is_a_peripheral);
	566	static USB_UDC_ATTR(b_hnp_enable);
	567	static USB_UDC_ATTR(a_hnp_support);
	568	static USB_UDC_ATTR(a_alt_hnp_support);
	569
	570	static struct attribute *usb_udc_attrs[] = {
	571	&dev_attr_srp.attr,
	572	&dev_attr_soft_connect.attr,
49401f41	573	&dev_attr_state.attr,
d327ab5b MN	574	&dev_attr_current_speed.attr,
d327ab5b MN	575	&dev_attr_maximum_speed.attr,
2ccea03a	576
2ccea03a FB	577	&dev_attr_is_otg.attr,
	578	&dev_attr_is_a_peripheral.attr,
	579	&dev_attr_b_hnp_enable.attr,
	580	&dev_attr_a_hnp_support.attr,
	581	&dev_attr_a_alt_hnp_support.attr,
	582	NULL,
	583	};
	584
	585	static const struct attribute_group usb_udc_attr_group = {
	586	.attrs = usb_udc_attrs,
	587	};
	588
	589	static const struct attribute_group *usb_udc_attr_groups[] = {
	590	&usb_udc_attr_group,
	591	NULL,
	592	};
	593
	594	static int usb_udc_uevent(struct device dev, struct kobj_uevent_env env)
	595	{
	596	struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
	597	int ret;
	598
	599	ret = add_uevent_var(env, "USB_UDC_NAME=%s", udc->gadget->name);
	600	if (ret) {
	601	dev_err(dev, "failed to add uevent USB_UDC_NAME\n");
	602	return ret;
	603	}
	604
	605	if (udc->driver) {
	606	ret = add_uevent_var(env, "USB_UDC_DRIVER=%s",
	607	udc->driver->function);
	608	if (ret) {
	609	dev_err(dev, "failed to add uevent USB_UDC_DRIVER\n");
	610	return ret;
	611	}
	612	}
	613
	614	return 0;
	615	}
	616
	617	static int __init usb_udc_init(void)
	618	{
	619	udc_class = class_create(THIS_MODULE, "udc");
	620	if (IS_ERR(udc_class)) {
	621	pr_err("failed to create udc class --> %ld\n",
	622	PTR_ERR(udc_class));
	623	return PTR_ERR(udc_class);
	624	}
	625
	626	udc_class->dev_uevent = usb_udc_uevent;
2ccea03a FB	627	return 0;
	628	}
	629	subsys_initcall(usb_udc_init);
	630
	631	static void __exit usb_udc_exit(void)
	632	{
	633	class_destroy(udc_class);
	634	}
	635	module_exit(usb_udc_exit);
	636
	637	MODULE_DESCRIPTION("UDC Framework");
	638	MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
	639	MODULE_LICENSE("GPL v2");