// SPDX-License-Identifier: GPL-2.0 /* * udc.c - Core UDC Framework * * Copyright (C) 2010 Texas Instruments * Author: Felipe Balbi <[email protected]> */ #define pr_fmt(fmt) … #include <linux/kernel.h> #include <linux/module.h> #include <linux/device.h> #include <linux/list.h> #include <linux/idr.h> #include <linux/err.h> #include <linux/dma-mapping.h> #include <linux/sched/task_stack.h> #include <linux/workqueue.h> #include <linux/usb/ch9.h> #include <linux/usb/gadget.h> #include <linux/usb.h> #include "trace.h" static DEFINE_IDA(gadget_id_numbers); static const struct bus_type gadget_bus_type; /** * 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 * @vbus: for udcs who care about vbus status, this value is real vbus status; * for udcs who do not care about vbus status, this value is always true * @started: the UDC's started state. True if the UDC had started. * @allow_connect: Indicates whether UDC is allowed to be pulled up. * Set/cleared by gadget_(un)bind_driver() after gadget driver is bound or * unbound. * @vbus_work: work routine to handle VBUS status change notifications. * @connect_lock: protects udc->started, gadget->connect, * gadget->allow_connect and gadget->deactivate. The routines * usb_gadget_connect_locked(), usb_gadget_disconnect_locked(), * usb_udc_connect_control_locked(), usb_gadget_udc_start_locked() and * usb_gadget_udc_stop_locked() are called with this lock held. * * 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 { … }; static const struct class udc_class; static LIST_HEAD(udc_list); /* Protects udc_list, udc->driver, driver->is_bound, and related calls */ static DEFINE_MUTEX(udc_lock); /* ------------------------------------------------------------------------- */ /** * usb_ep_set_maxpacket_limit - set maximum packet size limit for endpoint * @ep:the endpoint being configured * @maxpacket_limit:value of maximum packet size limit * * This function should be used only in UDC drivers to initialize endpoint * (usually in probe function). */ void usb_ep_set_maxpacket_limit(struct usb_ep *ep, unsigned maxpacket_limit) { … } EXPORT_SYMBOL_GPL(…); /** * usb_ep_enable - configure endpoint, making it usable * @ep:the endpoint being configured. may not be the endpoint named "ep0". * drivers discover endpoints through the ep_list of a usb_gadget. * * When configurations are set, or when interface settings change, the driver * will enable or disable the relevant endpoints. while it is enabled, an * endpoint may be used for i/o until the driver receives a disconnect() from * the host or until the endpoint is disabled. * * the ep0 implementation (which calls this routine) must ensure that the * hardware capabilities of each endpoint match the descriptor provided * for it. for example, an endpoint named "ep2in-bulk" would be usable * for interrupt transfers as well as bulk, but it likely couldn't be used * for iso transfers or for endpoint 14. some endpoints are fully * configurable, with more generic names like "ep-a". (remember that for * USB, "in" means "towards the USB host".) * * This routine may be called in an atomic (interrupt) context. * * returns zero, or a negative error code. */ int usb_ep_enable(struct usb_ep *ep) { … } EXPORT_SYMBOL_GPL(…); /** * usb_ep_disable - endpoint is no longer usable * @ep:the endpoint being unconfigured. may not be the endpoint named "ep0". * * no other task may be using this endpoint when this is called. * any pending and uncompleted requests will complete with status * indicating disconnect (-ESHUTDOWN) before this call returns. * gadget drivers must call usb_ep_enable() again before queueing * requests to the endpoint. * * This routine may be called in an atomic (interrupt) context. * * returns zero, or a negative error code. */ int usb_ep_disable(struct usb_ep *ep) { … } EXPORT_SYMBOL_GPL(…); /** * usb_ep_alloc_request - allocate a request object to use with this endpoint * @ep:the endpoint to be used with with the request * @gfp_flags:GFP_* flags to use * * Request objects must be allocated with this call, since they normally * need controller-specific setup and may even need endpoint-specific * resources such as allocation of DMA descriptors. * Requests may be submitted with usb_ep_queue(), and receive a single * completion callback. Free requests with usb_ep_free_request(), when * they are no longer needed. * * Returns the request, or null if one could not be allocated. */ struct usb_request *usb_ep_alloc_request(struct usb_ep *ep, gfp_t gfp_flags) { … } EXPORT_SYMBOL_GPL(…); /** * usb_ep_free_request - frees a request object * @ep:the endpoint associated with the request * @req:the request being freed * * Reverses the effect of usb_ep_alloc_request(). * Caller guarantees the request is not queued, and that it will * no longer be requeued (or otherwise used). */ void usb_ep_free_request(struct usb_ep *ep, struct usb_request *req) { … } EXPORT_SYMBOL_GPL(…); /** * usb_ep_queue - queues (submits) an I/O request to an endpoint. * @ep:the endpoint associated with the request * @req:the request being submitted * @gfp_flags: GFP_* flags to use in case the lower level driver couldn't * pre-allocate all necessary memory with the request. * * This tells the device controller to perform the specified request through * that endpoint (reading or writing a buffer). When the request completes, * including being canceled by usb_ep_dequeue(), the request's completion * routine is called to return the request to the driver. Any endpoint * (except control endpoints like ep0) may have more than one transfer * request queued; they complete in FIFO order. Once a gadget driver * submits a request, that request may not be examined or modified until it * is given back to that driver through the completion callback. * * Each request is turned into one or more packets. The controller driver * never merges adjacent requests into the same packet. OUT transfers * will sometimes use data that's already buffered in the hardware. * Drivers can rely on the fact that the first byte of the request's buffer * always corresponds to the first byte of some USB packet, for both * IN and OUT transfers. * * Bulk endpoints can queue any amount of data; the transfer is packetized * automatically. The last packet will be short if the request doesn't fill it * out completely. Zero length packets (ZLPs) should be avoided in portable * protocols since not all usb hardware can successfully handle zero length * packets. (ZLPs may be explicitly written, and may be implicitly written if * the request 'zero' flag is set.) Bulk endpoints may also be used * for interrupt transfers; but the reverse is not true, and some endpoints * won't support every interrupt transfer. (Such as 768 byte packets.) * * Interrupt-only endpoints are less functional than bulk endpoints, for * example by not supporting queueing or not handling buffers that are * larger than the endpoint's maxpacket size. They may also treat data * toggle differently. * * Control endpoints ... after getting a setup() callback, the driver queues * one response (even if it would be zero length). That enables the * status ack, after transferring data as specified in the response. Setup * functions may return negative error codes to generate protocol stalls. * (Note that some USB device controllers disallow protocol stall responses * in some cases.) When control responses are deferred (the response is * written after the setup callback returns), then usb_ep_set_halt() may be * used on ep0 to trigger protocol stalls. Depending on the controller, * it may not be possible to trigger a status-stage protocol stall when the * data stage is over, that is, from within the response's completion * routine. * * For periodic endpoints, like interrupt or isochronous ones, the usb host * arranges to poll once per interval, and the gadget driver usually will * have queued some data to transfer at that time. * * Note that @req's ->complete() callback must never be called from * within usb_ep_queue() as that can create deadlock situations. * * This routine may be called in interrupt context. * * Returns zero, or a negative error code. Endpoints that are not enabled * report errors; errors will also be * reported when the usb peripheral is disconnected. * * If and only if @req is successfully queued (the return value is zero), * @req->complete() will be called exactly once, when the Gadget core and * UDC are finished with the request. When the completion function is called, * control of the request is returned to the device driver which submitted it. * The completion handler may then immediately free or reuse @req. */ int usb_ep_queue(struct usb_ep *ep, struct usb_request *req, gfp_t gfp_flags) { … } EXPORT_SYMBOL_GPL(…); /** * usb_ep_dequeue - dequeues (cancels, unlinks) an I/O request from an endpoint * @ep:the endpoint associated with the request * @req:the request being canceled * * If the request is still active on the endpoint, it is dequeued and * eventually its completion routine is called (with status -ECONNRESET); * else a negative error code is returned. This routine is asynchronous, * that is, it may return before the completion routine runs. * * Note that some hardware can't clear out write fifos (to unlink the request * at the head of the queue) except as part of disconnecting from usb. Such * restrictions prevent drivers from supporting configuration changes, * even to configuration zero (a "chapter 9" requirement). * * This routine may be called in interrupt context. */ int usb_ep_dequeue(struct usb_ep *ep, struct usb_request *req) { … } EXPORT_SYMBOL_GPL(…); /** * usb_ep_set_halt - sets the endpoint halt feature. * @ep: the non-isochronous endpoint being stalled * * Use this to stall an endpoint, perhaps as an error report. * Except for control endpoints, * the endpoint stays halted (will not stream any data) until the host * clears this feature; drivers may need to empty the endpoint's request * queue first, to make sure no inappropriate transfers happen. * * Note that while an endpoint CLEAR_FEATURE will be invisible to the * gadget driver, a SET_INTERFACE will not be. To reset endpoints for the * current altsetting, see usb_ep_clear_halt(). When switching altsettings, * it's simplest to use usb_ep_enable() or usb_ep_disable() for the endpoints. * * This routine may be called in interrupt context. * * Returns zero, or a negative error code. On success, this call sets * underlying hardware state that blocks data transfers. * Attempts to halt IN endpoints will fail (returning -EAGAIN) if any * transfer requests are still queued, or if the controller hardware * (usually a FIFO) still holds bytes that the host hasn't collected. */ int usb_ep_set_halt(struct usb_ep *ep) { … } EXPORT_SYMBOL_GPL(…); /** * usb_ep_clear_halt - clears endpoint halt, and resets toggle * @ep:the bulk or interrupt endpoint being reset * * Use this when responding to the standard usb "set interface" request, * for endpoints that aren't reconfigured, after clearing any other state * in the endpoint's i/o queue. * * This routine may be called in interrupt context. * * Returns zero, or a negative error code. On success, this call clears * the underlying hardware state reflecting endpoint halt and data toggle. * Note that some hardware can't support this request (like pxa2xx_udc), * and accordingly can't correctly implement interface altsettings. */ int usb_ep_clear_halt(struct usb_ep *ep) { … } EXPORT_SYMBOL_GPL(…); /** * usb_ep_set_wedge - sets the halt feature and ignores clear requests * @ep: the endpoint being wedged * * Use this to stall an endpoint and ignore CLEAR_FEATURE(HALT_ENDPOINT) * requests. If the gadget driver clears the halt status, it will * automatically unwedge the endpoint. * * This routine may be called in interrupt context. * * Returns zero on success, else negative errno. */ int usb_ep_set_wedge(struct usb_ep *ep) { … } EXPORT_SYMBOL_GPL(…); /** * usb_ep_fifo_status - returns number of bytes in fifo, or error * @ep: the endpoint whose fifo status is being checked. * * FIFO endpoints may have "unclaimed data" in them in certain cases, * such as after aborted transfers. Hosts may not have collected all * the IN data written by the gadget driver (and reported by a request * completion). The gadget driver may not have collected all the data * written OUT to it by the host. Drivers that need precise handling for * fault reporting or recovery may need to use this call. * * This routine may be called in interrupt context. * * This returns the number of such bytes in the fifo, or a negative * errno if the endpoint doesn't use a FIFO or doesn't support such * precise handling. */ int usb_ep_fifo_status(struct usb_ep *ep) { … } EXPORT_SYMBOL_GPL(…); /** * usb_ep_fifo_flush - flushes contents of a fifo * @ep: the endpoint whose fifo is being flushed. * * This call may be used to flush the "unclaimed data" that may exist in * an endpoint fifo after abnormal transaction terminations. The call * must never be used except when endpoint is not being used for any * protocol translation. * * This routine may be called in interrupt context. */ void usb_ep_fifo_flush(struct usb_ep *ep) { … } EXPORT_SYMBOL_GPL(…); /* ------------------------------------------------------------------------- */ /** * usb_gadget_frame_number - returns the current frame number * @gadget: controller that reports the frame number * * Returns the usb frame number, normally eleven bits from a SOF packet, * or negative errno if this device doesn't support this capability. */ int usb_gadget_frame_number(struct usb_gadget *gadget) { … } EXPORT_SYMBOL_GPL(…); /** * usb_gadget_wakeup - tries to wake up the host connected to this gadget * @gadget: controller used to wake up the host * * Returns zero on success, else negative error code if the hardware * doesn't support such attempts, or its support has not been enabled * by the usb host. Drivers must return device descriptors that report * their ability to support this, or hosts won't enable it. * * This may also try to use SRP to wake the host and start enumeration, * even if OTG isn't otherwise in use. OTG devices may also start * remote wakeup even when hosts don't explicitly enable it. */ int usb_gadget_wakeup(struct usb_gadget *gadget) { … } EXPORT_SYMBOL_GPL(…); /** * usb_gadget_set_remote_wakeup - configures the device remote wakeup feature. * @gadget:the device being configured for remote wakeup * @set:value to be configured. * * set to one to enable remote wakeup feature and zero to disable it. * * returns zero on success, else negative errno. */ int usb_gadget_set_remote_wakeup(struct usb_gadget *gadget, int set) { … } EXPORT_SYMBOL_GPL(…); /** * usb_gadget_set_selfpowered - sets the device selfpowered feature. * @gadget:the device being declared as self-powered * * this affects the device status reported by the hardware driver * to reflect that it now has a local power supply. * * returns zero on success, else negative errno. */ int usb_gadget_set_selfpowered(struct usb_gadget *gadget) { … } EXPORT_SYMBOL_GPL(…); /** * usb_gadget_clear_selfpowered - clear the device selfpowered feature. * @gadget:the device being declared as bus-powered * * this affects the device status reported by the hardware driver. * some hardware may not support bus-powered operation, in which * case this feature's value can never change. * * returns zero on success, else negative errno. */ int usb_gadget_clear_selfpowered(struct usb_gadget *gadget) { … } EXPORT_SYMBOL_GPL(…); /** * usb_gadget_vbus_connect - Notify controller that VBUS is powered * @gadget:The device which now has VBUS power. * Context: can sleep * * This call is used by a driver for an external transceiver (or GPIO) * that detects a VBUS power session starting. Common responses include * resuming the controller, activating the D+ (or D-) pullup to let the * host detect that a USB device is attached, and starting to draw power * (8mA or possibly more, especially after SET_CONFIGURATION). * * Returns zero on success, else negative errno. */ int usb_gadget_vbus_connect(struct usb_gadget *gadget) { … } EXPORT_SYMBOL_GPL(…); /** * usb_gadget_vbus_draw - constrain controller's VBUS power usage * @gadget:The device whose VBUS usage is being described * @mA:How much current to draw, in milliAmperes. This should be twice * the value listed in the configuration descriptor bMaxPower field. * * This call is used by gadget drivers during SET_CONFIGURATION calls, * reporting how much power the device may consume. For example, this * could affect how quickly batteries are recharged. * * Returns zero on success, else negative errno. */ int usb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA) { … } EXPORT_SYMBOL_GPL(…); /** * usb_gadget_vbus_disconnect - notify controller about VBUS session end * @gadget:the device whose VBUS supply is being described * Context: can sleep * * This call is used by a driver for an external transceiver (or GPIO) * that detects a VBUS power session ending. Common responses include * reversing everything done in usb_gadget_vbus_connect(). * * Returns zero on success, else negative errno. */ int usb_gadget_vbus_disconnect(struct usb_gadget *gadget) { … } EXPORT_SYMBOL_GPL(…); static int usb_gadget_connect_locked(struct usb_gadget *gadget) __must_hold(&gadget->udc->connect_lock) { … } /** * usb_gadget_connect - software-controlled connect to USB host * @gadget:the peripheral being connected * * Enables the D+ (or potentially D-) pullup. The host will start * enumerating this gadget when the pullup is active and a VBUS session * is active (the link is powered). * * Returns zero on success, else negative errno. */ int usb_gadget_connect(struct usb_gadget *gadget) { … } EXPORT_SYMBOL_GPL(…); static int usb_gadget_disconnect_locked(struct usb_gadget *gadget) __must_hold(&gadget->udc->connect_lock) { … } /** * usb_gadget_disconnect - software-controlled disconnect from USB host * @gadget:the peripheral being disconnected * * Disables the D+ (or potentially D-) pullup, which the host may see * as a disconnect (when a VBUS session is active). Not all systems * support software pullup controls. * * Following a successful disconnect, invoke the ->disconnect() callback * for the current gadget driver so that UDC drivers don't need to. * * Returns zero on success, else negative errno. */ int usb_gadget_disconnect(struct usb_gadget *gadget) { … } EXPORT_SYMBOL_GPL(…); /** * usb_gadget_deactivate - deactivate function which is not ready to work * @gadget: the peripheral being deactivated * * This routine may be used during the gadget driver bind() call to prevent * the peripheral from ever being visible to the USB host, unless later * usb_gadget_activate() is called. For example, user mode components may * need to be activated before the system can talk to hosts. * * This routine may sleep; it must not be called in interrupt context * (such as from within a gadget driver's disconnect() callback). * * Returns zero on success, else negative errno. */ int usb_gadget_deactivate(struct usb_gadget *gadget) { … } EXPORT_SYMBOL_GPL(…); /** * usb_gadget_activate - activate function which is not ready to work * @gadget: the peripheral being activated * * This routine activates gadget which was previously deactivated with * usb_gadget_deactivate() call. It calls usb_gadget_connect() if needed. * * This routine may sleep; it must not be called in interrupt context. * * Returns zero on success, else negative errno. */ int usb_gadget_activate(struct usb_gadget *gadget) { … } EXPORT_SYMBOL_GPL(…); /* ------------------------------------------------------------------------- */ #ifdef CONFIG_HAS_DMA int usb_gadget_map_request_by_dev(struct device *dev, struct usb_request *req, int is_in) { … } EXPORT_SYMBOL_GPL(…); int usb_gadget_map_request(struct usb_gadget *gadget, struct usb_request *req, int is_in) { … } EXPORT_SYMBOL_GPL(…); void usb_gadget_unmap_request_by_dev(struct device *dev, struct usb_request *req, int is_in) { … } EXPORT_SYMBOL_GPL(…); void usb_gadget_unmap_request(struct usb_gadget *gadget, struct usb_request *req, int is_in) { … } EXPORT_SYMBOL_GPL(…); #endif /* CONFIG_HAS_DMA */ /* ------------------------------------------------------------------------- */ /** * usb_gadget_giveback_request - give the request back to the gadget layer * @ep: the endpoint to be used with with the request * @req: the request being given back * * 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) { … } EXPORT_SYMBOL_GPL(…); /* ------------------------------------------------------------------------- */ /** * gadget_find_ep_by_name - returns ep whose name is the same as sting passed * in second parameter or NULL if searched endpoint not found * @g: controller to check for quirk * @name: name of searched endpoint */ struct usb_ep *gadget_find_ep_by_name(struct usb_gadget *g, const char *name) { … } EXPORT_SYMBOL_GPL(…); /* ------------------------------------------------------------------------- */ int usb_gadget_ep_match_desc(struct usb_gadget *gadget, struct usb_ep *ep, struct usb_endpoint_descriptor *desc, struct usb_ss_ep_comp_descriptor *ep_comp) { … } EXPORT_SYMBOL_GPL(…); /** * usb_gadget_check_config - checks if the UDC can support the binded * configuration * @gadget: controller to check the USB configuration * * Ensure that a UDC is able to support the requested resources by a * configuration, and that there are no resource limitations, such as * internal memory allocated to all requested endpoints. * * Returns zero on success, else a negative errno. */ int usb_gadget_check_config(struct usb_gadget *gadget) { … } EXPORT_SYMBOL_GPL(…); /* ------------------------------------------------------------------------- */ static void usb_gadget_state_work(struct work_struct *work) { … } void usb_gadget_set_state(struct usb_gadget *gadget, enum usb_device_state state) { … } EXPORT_SYMBOL_GPL(…); /* ------------------------------------------------------------------------- */ /* Acquire connect_lock before calling this function. */ static int usb_udc_connect_control_locked(struct usb_udc *udc) __must_hold(&udc->connect_lock) { … } static void vbus_event_work(struct work_struct *work) { … } /** * usb_udc_vbus_handler - updates the udc core vbus status, and try to * connect or disconnect gadget * @gadget: The gadget which vbus change occurs * @status: The vbus status * * The udc driver calls it when it wants to connect or disconnect gadget * according to vbus status. * * This function can be invoked from interrupt context by irq handlers of * the gadget drivers, however, usb_udc_connect_control() has to run in * non-atomic context due to the following: * a. Some of the gadget driver implementations expect the ->pullup * callback to be invoked in non-atomic context. * b. usb_gadget_disconnect() acquires udc_lock which is a mutex. * Hence offload invocation of usb_udc_connect_control() to workqueue. */ void usb_udc_vbus_handler(struct usb_gadget *gadget, bool status) { … } EXPORT_SYMBOL_GPL(…); /** * 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) { … } EXPORT_SYMBOL_GPL(…); /** * usb_gadget_udc_start_locked - 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. * * Caller should acquire connect_lock before invoking this function. */ static inline int usb_gadget_udc_start_locked(struct usb_udc *udc) __must_hold(&udc->connect_lock) { … } /** * usb_gadget_udc_stop_locked - tells usb device controller we don't need it anymore * @udc: The UDC to be stopped * * 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. * * Caller should acquire connect lock before invoking this function. */ static inline void usb_gadget_udc_stop_locked(struct usb_udc *udc) __must_hold(&udc->connect_lock) { … } /** * usb_gadget_udc_set_speed - tells usb device controller speed supported by * current driver * @udc: The device we want to set maximum speed * @speed: The maximum speed to allowed to run * * This call is issued by the UDC Class driver before calling * usb_gadget_udc_start() in order to make sure that we don't try to * connect on speeds the gadget driver doesn't support. */ static inline void usb_gadget_udc_set_speed(struct usb_udc *udc, enum usb_device_speed speed) { … } /** * usb_gadget_enable_async_callbacks - tell usb device controller to enable asynchronous callbacks * @udc: The UDC which should enable async callbacks * * This routine is used when binding gadget drivers. It undoes the effect * of usb_gadget_disable_async_callbacks(); the UDC driver should enable IRQs * (if necessary) and resume issuing callbacks. * * This routine will always be called in process context. */ static inline void usb_gadget_enable_async_callbacks(struct usb_udc *udc) { … } /** * usb_gadget_disable_async_callbacks - tell usb device controller to disable asynchronous callbacks * @udc: The UDC which should disable async callbacks * * This routine is used when unbinding gadget drivers. It prevents a race: * The UDC driver doesn't know when the gadget driver's ->unbind callback * runs, so unless it is told to disable asynchronous callbacks, it might * issue a callback (such as ->disconnect) after the unbind has completed. * * After this function runs, the UDC driver must suppress all ->suspend, * ->resume, ->disconnect, ->reset, and ->setup callbacks to the gadget driver * until async callbacks are again enabled. A simple-minded but effective * way to accomplish this is to tell the UDC hardware not to generate any * more IRQs. * * Request completion callbacks must still be issued. However, it's okay * to defer them until the request is cancelled, since the pull-up will be * turned off during the time period when async callbacks are disabled. * * This routine will always be called in process context. */ static inline void usb_gadget_disable_async_callbacks(struct usb_udc *udc) { … } /** * 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) { … } static const struct attribute_group *usb_udc_attr_groups[]; static void usb_udc_nop_release(struct device *dev) { … } /** * usb_initialize_gadget - initialize a gadget and its embedded struct device * @parent: the parent device to this udc. Usually the controller driver's * device. * @gadget: the gadget to be initialized. * @release: a gadget release function. */ void usb_initialize_gadget(struct device *parent, struct usb_gadget *gadget, void (*release)(struct device *dev)) { … } EXPORT_SYMBOL_GPL(…); /** * usb_add_gadget - adds a new gadget to the udc class driver list * @gadget: the gadget to be added to the list. * * Returns zero on success, negative errno otherwise. * Does not do a final usb_put_gadget() if an error occurs. */ int usb_add_gadget(struct usb_gadget *gadget) { … } EXPORT_SYMBOL_GPL(…); /** * 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. * Calls the gadget release function in the latter case. */ int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget, void (*release)(struct device *dev)) { … } EXPORT_SYMBOL_GPL(…); /** * usb_get_gadget_udc_name - get the name of the first UDC controller * This functions returns the name of the first UDC controller in the system. * Please note that this interface is usefull only for legacy drivers which * assume that there is only one UDC controller in the system and they need to * get its name before initialization. There is no guarantee that the UDC * of the returned name will be still available, when gadget driver registers * itself. * * Returns pointer to string with UDC controller name on success, NULL * otherwise. Caller should kfree() returned string. */ char *usb_get_gadget_udc_name(void) { … } EXPORT_SYMBOL_GPL(…); /** * 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) { … } EXPORT_SYMBOL_GPL(…); /** * usb_del_gadget - deletes a gadget and unregisters its udc * @gadget: the gadget to be deleted. * * This will unbind @gadget, if it is bound. * It will not do a final usb_put_gadget(). */ void usb_del_gadget(struct usb_gadget *gadget) { … } EXPORT_SYMBOL_GPL(…); /** * usb_del_gadget_udc - unregisters a gadget * @gadget: the gadget to be unregistered. * * Calls usb_del_gadget() and does a final usb_put_gadget(). */ void usb_del_gadget_udc(struct usb_gadget *gadget) { … } EXPORT_SYMBOL_GPL(…); /* ------------------------------------------------------------------------- */ static int gadget_match_driver(struct device *dev, const struct device_driver *drv) { … } static int gadget_bind_driver(struct device *dev) { … } static void gadget_unbind_driver(struct device *dev) { … } /* ------------------------------------------------------------------------- */ int usb_gadget_register_driver_owner(struct usb_gadget_driver *driver, struct module *owner, const char *mod_name) { … } EXPORT_SYMBOL_GPL(…); int usb_gadget_unregister_driver(struct usb_gadget_driver *driver) { … } EXPORT_SYMBOL_GPL(…); /* ------------------------------------------------------------------------- */ static ssize_t srp_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) { … } static DEVICE_ATTR_WO(srp); static ssize_t soft_connect_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) { … } static DEVICE_ATTR_WO(soft_connect); static ssize_t state_show(struct device *dev, struct device_attribute *attr, char *buf) { … } static DEVICE_ATTR_RO(state); static ssize_t function_show(struct device *dev, struct device_attribute *attr, char *buf) { … } static DEVICE_ATTR_RO(function); #define USB_UDC_SPEED_ATTR(name, param) … static USB_UDC_SPEED_ATTR(current_speed, speed); static USB_UDC_SPEED_ATTR(maximum_speed, max_speed); #define USB_UDC_ATTR(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 USB_UDC_ATTR(is_selfpowered); static struct attribute *usb_udc_attrs[] = …; static const struct attribute_group usb_udc_attr_group = …; static const struct attribute_group *usb_udc_attr_groups[] = …; static int usb_udc_uevent(const struct device *dev, struct kobj_uevent_env *env) { … } static const struct class udc_class = …; static const struct bus_type gadget_bus_type = …; static int __init usb_udc_init(void) { … } subsys_initcall(usb_udc_init); static void __exit usb_udc_exit(void) { … } module_exit(usb_udc_exit); MODULE_DESCRIPTION(…) …; MODULE_AUTHOR(…) …; MODULE_LICENSE(…) …;