drivers/usb/gadget/udc/udc-core.c - manifest_repos/bootloader - Git at Google

 /**
  * udc-core.c - Core UDC Framework
  *
  * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com
  *
  * Author: Felipe Balbi <balbi@ti.com>
  *
  * Taken from Linux Kernel v3.19-rc1 (drivers/usb/gadget/udc-core.c) and ported
  * to uboot.
  *
  * commit 02e8c96627 : usb: gadget: udc: core: prepend udc_attach_driver with
  *		       usb_
  *
  * SPDX-License-Identifier:     GPL-2.0
  */

 #include <linux/compat.h>
 #include <malloc.h>
 #include <asm/cache.h>
 #include <asm/dma-mapping.h>
 #include <common.h>

 #include <linux/usb/ch9.h>
 #include <linux/usb/gadget.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);
 DEFINE_MUTEX(udc_lock);

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

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

 	req->dma = dma_map_single(req->buf, req->length,
 				  is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);

 	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;

 	dma_unmap_single((void *)(uintptr_t)req->dma, req->length,
 			 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
 }
 EXPORT_SYMBOL_GPL(usb_gadget_unmap_request);

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

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

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

 void usb_gadget_set_state(struct usb_gadget *gadget,
 		enum usb_device_state state)
 {
 	gadget->state = state;
 }
 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
  * @udc: The UDC to be started
  *
  * 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_udc *udc)
 {
 	return udc->gadget->ops->udc_start(udc->gadget, udc->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_udc *udc)
 {
 	udc->gadget->ops->udc_stop(udc->gadget);
 }

 /**
  * 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);
 	kfree(udc);
 }

 /**
  * 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");
 	gadget->dev.parent = parent;

 	udc->dev.release = usb_udc_release;
 	udc->dev.class = udc_class;
 	udc->dev.parent = parent;

 	udc->gadget = gadget;

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

 	usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED);

 	mutex_unlock(&udc_lock);

 	return 0;

 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->driver->function);

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

 	udc->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);
 }
 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;

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

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

 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;
 	}

 	printf("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_register_driver(struct usb_gadget_driver *driver)
 {
 	return usb_gadget_probe_driver(driver);
 }
 EXPORT_SYMBOL_GPL(usb_gadget_register_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);

 MODULE_DESCRIPTION("UDC Framework");
 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
 MODULE_LICENSE("GPL v2");
	/**
	* udc-core.c - Core UDC Framework
	*
	* Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com
	*
	* Author: Felipe Balbi <balbi@ti.com>
	*
	* Taken from Linux Kernel v3.19-rc1 (drivers/usb/gadget/udc-core.c) and ported
	* to uboot.
	*
	* commit 02e8c96627 : usb: gadget: udc: core: prepend udc_attach_driver with
	* usb_
	*
	* SPDX-License-Identifier: GPL-2.0
	*/

	#include <linux/compat.h>
	#include <malloc.h>
	#include <asm/cache.h>
	#include <asm/dma-mapping.h>
	#include <common.h>

	#include <linux/usb/ch9.h>
	#include <linux/usb/gadget.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);
	DEFINE_MUTEX(udc_lock);

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

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

	req->dma = dma_map_single(req->buf, req->length,
	is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);

	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;

	dma_unmap_single((void *)(uintptr_t)req->dma, req->length,
	is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
	}
	EXPORT_SYMBOL_GPL(usb_gadget_unmap_request);

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

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

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

	void usb_gadget_set_state(struct usb_gadget *gadget,
	enum usb_device_state state)
	{
	gadget->state = state;
	}
	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
	* @udc: The UDC to be started
	*
	* 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_udc *udc)
	{
	return udc->gadget->ops->udc_start(udc->gadget, udc->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_udc *udc)
	{
	udc->gadget->ops->udc_stop(udc->gadget);
	}

	/**
	* 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);
	kfree(udc);
	}

	/**
	* 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");
	gadget->dev.parent = parent;

	udc->dev.release = usb_udc_release;
	udc->dev.class = udc_class;
	udc->dev.parent = parent;

	udc->gadget = gadget;

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

	usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED);

	mutex_unlock(&udc_lock);

	return 0;

	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->driver->function);

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

	udc->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);
	}
	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;

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

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

	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;
	}

	printf("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_register_driver(struct usb_gadget_driver *driver)
	{
	return usb_gadget_probe_driver(driver);
	}
	EXPORT_SYMBOL_GPL(usb_gadget_register_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);

	MODULE_DESCRIPTION("UDC Framework");
	MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
	MODULE_LICENSE("GPL v2");