diff options
Diffstat (limited to 'drivers/usb/gadget/udc/core.c')
| -rw-r--r-- | drivers/usb/gadget/udc/core.c | 1877 |
1 files changed, 1877 insertions, 0 deletions
diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c new file mode 100644 index 000000000..c40f2ecbe --- /dev/null +++ b/drivers/usb/gadget/udc/core.c @@ -0,0 +1,1877 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * udc.c - Core UDC Framework + * + * Copyright (C) 2010 Texas Instruments + * Author: Felipe Balbi <balbi@ti.com> + */ + +#define pr_fmt(fmt) "UDC core: " 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 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 { + struct usb_gadget_driver *driver; + struct usb_gadget *gadget; + struct device dev; + struct list_head list; + bool vbus; + bool started; + bool allow_connect; + struct work_struct vbus_work; + struct mutex connect_lock; +}; + +static 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) +{ + ep->maxpacket_limit = maxpacket_limit; + ep->maxpacket = maxpacket_limit; + + trace_usb_ep_set_maxpacket_limit(ep, 0); +} +EXPORT_SYMBOL_GPL(usb_ep_set_maxpacket_limit); + +/** + * 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) +{ + int ret = 0; + + if (ep->enabled) + goto out; + + /* UDC drivers can't handle endpoints with maxpacket size 0 */ + if (usb_endpoint_maxp(ep->desc) == 0) { + /* + * We should log an error message here, but we can't call + * dev_err() because there's no way to find the gadget + * given only ep. + */ + ret = -EINVAL; + goto out; + } + + ret = ep->ops->enable(ep, ep->desc); + if (ret) + goto out; + + ep->enabled = true; + +out: + trace_usb_ep_enable(ep, ret); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_ep_enable); + +/** + * 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) +{ + int ret = 0; + + if (!ep->enabled) + goto out; + + ret = ep->ops->disable(ep); + if (ret) + goto out; + + ep->enabled = false; + +out: + trace_usb_ep_disable(ep, ret); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_ep_disable); + +/** + * 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) +{ + struct usb_request *req = NULL; + + req = ep->ops->alloc_request(ep, gfp_flags); + + trace_usb_ep_alloc_request(ep, req, req ? 0 : -ENOMEM); + + return req; +} +EXPORT_SYMBOL_GPL(usb_ep_alloc_request); + +/** + * 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) +{ + trace_usb_ep_free_request(ep, req, 0); + ep->ops->free_request(ep, req); +} +EXPORT_SYMBOL_GPL(usb_ep_free_request); + +/** + * 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) +{ + int ret = 0; + + if (WARN_ON_ONCE(!ep->enabled && ep->address)) { + ret = -ESHUTDOWN; + goto out; + } + + ret = ep->ops->queue(ep, req, gfp_flags); + +out: + trace_usb_ep_queue(ep, req, ret); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_ep_queue); + +/** + * 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) +{ + int ret; + + ret = ep->ops->dequeue(ep, req); + trace_usb_ep_dequeue(ep, req, ret); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_ep_dequeue); + +/** + * 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) +{ + int ret; + + ret = ep->ops->set_halt(ep, 1); + trace_usb_ep_set_halt(ep, ret); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_ep_set_halt); + +/** + * 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) +{ + int ret; + + ret = ep->ops->set_halt(ep, 0); + trace_usb_ep_clear_halt(ep, ret); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_ep_clear_halt); + +/** + * 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) +{ + int ret; + + if (ep->ops->set_wedge) + ret = ep->ops->set_wedge(ep); + else + ret = ep->ops->set_halt(ep, 1); + + trace_usb_ep_set_wedge(ep, ret); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_ep_set_wedge); + +/** + * 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) +{ + int ret; + + if (ep->ops->fifo_status) + ret = ep->ops->fifo_status(ep); + else + ret = -EOPNOTSUPP; + + trace_usb_ep_fifo_status(ep, ret); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_ep_fifo_status); + +/** + * 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) +{ + if (ep->ops->fifo_flush) + ep->ops->fifo_flush(ep); + + trace_usb_ep_fifo_flush(ep, 0); +} +EXPORT_SYMBOL_GPL(usb_ep_fifo_flush); + +/* ------------------------------------------------------------------------- */ + +/** + * 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) +{ + int ret; + + ret = gadget->ops->get_frame(gadget); + + trace_usb_gadget_frame_number(gadget, ret); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_gadget_frame_number); + +/** + * 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) +{ + int ret = 0; + + if (!gadget->ops->wakeup) { + ret = -EOPNOTSUPP; + goto out; + } + + ret = gadget->ops->wakeup(gadget); + +out: + trace_usb_gadget_wakeup(gadget, ret); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_gadget_wakeup); + +/** + * 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) +{ + int ret = 0; + + if (!gadget->ops->set_selfpowered) { + ret = -EOPNOTSUPP; + goto out; + } + + ret = gadget->ops->set_selfpowered(gadget, 1); + +out: + trace_usb_gadget_set_selfpowered(gadget, ret); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_gadget_set_selfpowered); + +/** + * 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) +{ + int ret = 0; + + if (!gadget->ops->set_selfpowered) { + ret = -EOPNOTSUPP; + goto out; + } + + ret = gadget->ops->set_selfpowered(gadget, 0); + +out: + trace_usb_gadget_clear_selfpowered(gadget, ret); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_gadget_clear_selfpowered); + +/** + * 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) +{ + int ret = 0; + + if (!gadget->ops->vbus_session) { + ret = -EOPNOTSUPP; + goto out; + } + + ret = gadget->ops->vbus_session(gadget, 1); + +out: + trace_usb_gadget_vbus_connect(gadget, ret); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_gadget_vbus_connect); + +/** + * 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) +{ + int ret = 0; + + if (!gadget->ops->vbus_draw) { + ret = -EOPNOTSUPP; + goto out; + } + + ret = gadget->ops->vbus_draw(gadget, mA); + if (!ret) + gadget->mA = mA; + +out: + trace_usb_gadget_vbus_draw(gadget, ret); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_gadget_vbus_draw); + +/** + * 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) +{ + int ret = 0; + + if (!gadget->ops->vbus_session) { + ret = -EOPNOTSUPP; + goto out; + } + + ret = gadget->ops->vbus_session(gadget, 0); + +out: + trace_usb_gadget_vbus_disconnect(gadget, ret); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_gadget_vbus_disconnect); + +static int usb_gadget_connect_locked(struct usb_gadget *gadget) + __must_hold(&gadget->udc->connect_lock) +{ + int ret = 0; + + if (!gadget->ops->pullup) { + ret = -EOPNOTSUPP; + goto out; + } + + if (gadget->deactivated || !gadget->udc->allow_connect || !gadget->udc->started) { + /* + * If the gadget isn't usable (because it is deactivated, + * unbound, or not yet started), we only save the new state. + * The gadget will be connected automatically when it is + * activated/bound/started. + */ + gadget->connected = true; + goto out; + } + + ret = gadget->ops->pullup(gadget, 1); + if (!ret) + gadget->connected = 1; + +out: + trace_usb_gadget_connect(gadget, ret); + + return ret; +} + +/** + * 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) +{ + int ret; + + mutex_lock(&gadget->udc->connect_lock); + ret = usb_gadget_connect_locked(gadget); + mutex_unlock(&gadget->udc->connect_lock); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_gadget_connect); + +static int usb_gadget_disconnect_locked(struct usb_gadget *gadget) + __must_hold(&gadget->udc->connect_lock) +{ + int ret = 0; + + if (!gadget->ops->pullup) { + ret = -EOPNOTSUPP; + goto out; + } + + if (!gadget->connected) + goto out; + + if (gadget->deactivated || !gadget->udc->started) { + /* + * If gadget is deactivated we only save new state. + * Gadget will stay disconnected after activation. + */ + gadget->connected = false; + goto out; + } + + ret = gadget->ops->pullup(gadget, 0); + if (!ret) + gadget->connected = 0; + + mutex_lock(&udc_lock); + if (gadget->udc->driver) + gadget->udc->driver->disconnect(gadget); + mutex_unlock(&udc_lock); + +out: + trace_usb_gadget_disconnect(gadget, ret); + + return ret; +} + +/** + * 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) +{ + int ret; + + mutex_lock(&gadget->udc->connect_lock); + ret = usb_gadget_disconnect_locked(gadget); + mutex_unlock(&gadget->udc->connect_lock); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_gadget_disconnect); + +/** + * 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) +{ + int ret = 0; + + mutex_lock(&gadget->udc->connect_lock); + if (gadget->deactivated) + goto unlock; + + if (gadget->connected) { + ret = usb_gadget_disconnect_locked(gadget); + if (ret) + goto unlock; + + /* + * If gadget was being connected before deactivation, we want + * to reconnect it in usb_gadget_activate(). + */ + gadget->connected = true; + } + gadget->deactivated = true; + +unlock: + mutex_unlock(&gadget->udc->connect_lock); + trace_usb_gadget_deactivate(gadget, ret); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_gadget_deactivate); + +/** + * 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) +{ + int ret = 0; + + mutex_lock(&gadget->udc->connect_lock); + if (!gadget->deactivated) + goto unlock; + + gadget->deactivated = false; + + /* + * If gadget has been connected before deactivation, or became connected + * while it was being deactivated, we call usb_gadget_connect(). + */ + if (gadget->connected) + ret = usb_gadget_connect_locked(gadget); + +unlock: + mutex_unlock(&gadget->udc->connect_lock); + trace_usb_gadget_activate(gadget, ret); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_gadget_activate); + +/* ------------------------------------------------------------------------- */ + +#ifdef CONFIG_HAS_DMA + +int usb_gadget_map_request_by_dev(struct device *dev, + struct usb_request *req, int is_in) +{ + if (req->length == 0) + return 0; + + if (req->num_sgs) { + int mapped; + + mapped = dma_map_sg(dev, req->sg, req->num_sgs, + is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE); + if (mapped == 0) { + dev_err(dev, "failed to map SGs\n"); + return -EFAULT; + } + + req->num_mapped_sgs = mapped; + } else { + if (is_vmalloc_addr(req->buf)) { + dev_err(dev, "buffer is not dma capable\n"); + return -EFAULT; + } else if (object_is_on_stack(req->buf)) { + dev_err(dev, "buffer is on stack\n"); + return -EFAULT; + } + + req->dma = dma_map_single(dev, req->buf, req->length, + is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE); + + if (dma_mapping_error(dev, req->dma)) { + dev_err(dev, "failed to map buffer\n"); + return -EFAULT; + } + + req->dma_mapped = 1; + } + + return 0; +} +EXPORT_SYMBOL_GPL(usb_gadget_map_request_by_dev); + +int usb_gadget_map_request(struct usb_gadget *gadget, + struct usb_request *req, int is_in) +{ + return usb_gadget_map_request_by_dev(gadget->dev.parent, req, is_in); +} +EXPORT_SYMBOL_GPL(usb_gadget_map_request); + +void usb_gadget_unmap_request_by_dev(struct device *dev, + struct usb_request *req, int is_in) +{ + if (req->length == 0) + return; + + if (req->num_mapped_sgs) { + dma_unmap_sg(dev, req->sg, req->num_sgs, + is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE); + + req->num_mapped_sgs = 0; + } else if (req->dma_mapped) { + dma_unmap_single(dev, req->dma, req->length, + is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE); + req->dma_mapped = 0; + } +} +EXPORT_SYMBOL_GPL(usb_gadget_unmap_request_by_dev); + +void usb_gadget_unmap_request(struct usb_gadget *gadget, + struct usb_request *req, int is_in) +{ + usb_gadget_unmap_request_by_dev(gadget->dev.parent, req, is_in); +} +EXPORT_SYMBOL_GPL(usb_gadget_unmap_request); + +#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) +{ + if (likely(req->status == 0)) + usb_led_activity(USB_LED_EVENT_GADGET); + + trace_usb_gadget_giveback_request(ep, req, 0); + + req->complete(ep, req); +} +EXPORT_SYMBOL_GPL(usb_gadget_giveback_request); + +/* ------------------------------------------------------------------------- */ + +/** + * 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) +{ + struct usb_ep *ep; + + gadget_for_each_ep(ep, g) { + if (!strcmp(ep->name, name)) + return ep; + } + + return NULL; +} +EXPORT_SYMBOL_GPL(gadget_find_ep_by_name); + +/* ------------------------------------------------------------------------- */ + +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) +{ + u8 type; + u16 max; + int num_req_streams = 0; + + /* endpoint already claimed? */ + if (ep->claimed) + return 0; + + type = usb_endpoint_type(desc); + max = usb_endpoint_maxp(desc); + + if (usb_endpoint_dir_in(desc) && !ep->caps.dir_in) + return 0; + if (usb_endpoint_dir_out(desc) && !ep->caps.dir_out) + return 0; + + if (max > ep->maxpacket_limit) + return 0; + + /* "high bandwidth" works only at high speed */ + if (!gadget_is_dualspeed(gadget) && usb_endpoint_maxp_mult(desc) > 1) + return 0; + + switch (type) { + case USB_ENDPOINT_XFER_CONTROL: + /* only support ep0 for portable CONTROL traffic */ + return 0; + case USB_ENDPOINT_XFER_ISOC: + if (!ep->caps.type_iso) + return 0; + /* ISO: limit 1023 bytes full speed, 1024 high/super speed */ + if (!gadget_is_dualspeed(gadget) && max > 1023) + return 0; + break; + case USB_ENDPOINT_XFER_BULK: + if (!ep->caps.type_bulk) + return 0; + if (ep_comp && gadget_is_superspeed(gadget)) { + /* Get the number of required streams from the + * EP companion descriptor and see if the EP + * matches it + */ + num_req_streams = ep_comp->bmAttributes & 0x1f; + if (num_req_streams > ep->max_streams) + return 0; + } + break; + case USB_ENDPOINT_XFER_INT: + /* Bulk endpoints handle interrupt transfers, + * except the toggle-quirky iso-synch kind + */ + if (!ep->caps.type_int && !ep->caps.type_bulk) + return 0; + /* INT: limit 64 bytes full speed, 1024 high/super speed */ + if (!gadget_is_dualspeed(gadget) && max > 64) + return 0; + break; + } + + return 1; +} +EXPORT_SYMBOL_GPL(usb_gadget_ep_match_desc); + +/** + * 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) +{ + if (gadget->ops->check_config) + return gadget->ops->check_config(gadget); + return 0; +} +EXPORT_SYMBOL_GPL(usb_gadget_check_config); + +/* ------------------------------------------------------------------------- */ + +static void usb_gadget_state_work(struct work_struct *work) +{ + struct usb_gadget *gadget = work_to_gadget(work); + struct usb_udc *udc = gadget->udc; + + if (udc) + 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); + +/* ------------------------------------------------------------------------- */ + +/* Acquire connect_lock before calling this function. */ +static void usb_udc_connect_control_locked(struct usb_udc *udc) __must_hold(&udc->connect_lock) +{ + if (udc->vbus) + usb_gadget_connect_locked(udc->gadget); + else + usb_gadget_disconnect_locked(udc->gadget); +} + +static void vbus_event_work(struct work_struct *work) +{ + struct usb_udc *udc = container_of(work, struct usb_udc, vbus_work); + + mutex_lock(&udc->connect_lock); + usb_udc_connect_control_locked(udc); + mutex_unlock(&udc->connect_lock); +} + +/** + * 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) +{ + struct usb_udc *udc = gadget->udc; + + if (udc) { + udc->vbus = status; + schedule_work(&udc->vbus_work); + } +} +EXPORT_SYMBOL_GPL(usb_udc_vbus_handler); + +/** + * 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_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) +{ + int ret; + + if (udc->started) { + dev_err(&udc->dev, "UDC had already started\n"); + return -EBUSY; + } + + ret = udc->gadget->ops->udc_start(udc->gadget, udc->driver); + if (!ret) + udc->started = true; + + return ret; +} + +/** + * 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) +{ + if (!udc->started) { + dev_err(&udc->dev, "UDC had already stopped\n"); + return; + } + + udc->gadget->ops->udc_stop(udc->gadget); + udc->started = false; +} + +/** + * 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) +{ + struct usb_gadget *gadget = udc->gadget; + enum usb_device_speed s; + + if (speed == USB_SPEED_UNKNOWN) + s = gadget->max_speed; + else + s = min(speed, gadget->max_speed); + + if (s == USB_SPEED_SUPER_PLUS && gadget->ops->udc_set_ssp_rate) + gadget->ops->udc_set_ssp_rate(gadget, gadget->max_ssp_rate); + else if (gadget->ops->udc_set_speed) + gadget->ops->udc_set_speed(gadget, s); +} + +/** + * 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) +{ + struct usb_gadget *gadget = udc->gadget; + + if (gadget->ops->udc_async_callbacks) + gadget->ops->udc_async_callbacks(gadget, true); +} + +/** + * 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) +{ + struct usb_gadget *gadget = udc->gadget; + + if (gadget->ops->udc_async_callbacks) + gadget->ops->udc_async_callbacks(gadget, false); +} + +/** + * 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_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)) +{ + INIT_WORK(&gadget->work, usb_gadget_state_work); + gadget->dev.parent = parent; + + if (release) + gadget->dev.release = release; + else + gadget->dev.release = usb_udc_nop_release; + + device_initialize(&gadget->dev); + gadget->dev.bus = &gadget_bus_type; +} +EXPORT_SYMBOL_GPL(usb_initialize_gadget); + +/** + * 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) +{ + struct usb_udc *udc; + int ret = -ENOMEM; + + udc = kzalloc(sizeof(*udc), GFP_KERNEL); + if (!udc) + goto error; + + 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 = gadget->dev.parent; + ret = dev_set_name(&udc->dev, "%s", + kobject_name(&gadget->dev.parent->kobj)); + if (ret) + goto err_put_udc; + + udc->gadget = gadget; + gadget->udc = udc; + mutex_init(&udc->connect_lock); + + udc->started = false; + + mutex_lock(&udc_lock); + list_add_tail(&udc->list, &udc_list); + mutex_unlock(&udc_lock); + INIT_WORK(&udc->vbus_work, vbus_event_work); + + ret = device_add(&udc->dev); + if (ret) + goto err_unlist_udc; + + usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED); + udc->vbus = true; + + ret = ida_alloc(&gadget_id_numbers, GFP_KERNEL); + if (ret < 0) + goto err_del_udc; + gadget->id_number = ret; + dev_set_name(&gadget->dev, "gadget.%d", ret); + + ret = device_add(&gadget->dev); + if (ret) + goto err_free_id; + + return 0; + + err_free_id: + ida_free(&gadget_id_numbers, gadget->id_number); + + err_del_udc: + flush_work(&gadget->work); + device_del(&udc->dev); + + err_unlist_udc: + mutex_lock(&udc_lock); + list_del(&udc->list); + mutex_unlock(&udc_lock); + + err_put_udc: + put_device(&udc->dev); + + error: + return ret; +} +EXPORT_SYMBOL_GPL(usb_add_gadget); + +/** + * 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)) +{ + int ret; + + usb_initialize_gadget(parent, gadget, release); + ret = usb_add_gadget(gadget); + if (ret) + usb_put_gadget(gadget); + return ret; +} +EXPORT_SYMBOL_GPL(usb_add_gadget_udc_release); + +/** + * 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) +{ + struct usb_udc *udc; + char *name = NULL; + + /* For now we take the first available UDC */ + mutex_lock(&udc_lock); + list_for_each_entry(udc, &udc_list, list) { + if (!udc->driver) { + name = kstrdup(udc->gadget->name, GFP_KERNEL); + break; + } + } + mutex_unlock(&udc_lock); + return name; +} +EXPORT_SYMBOL_GPL(usb_get_gadget_udc_name); + +/** + * 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); + +/** + * 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) +{ + struct usb_udc *udc = gadget->udc; + + if (!udc) + return; + + dev_vdbg(gadget->dev.parent, "unregistering gadget\n"); + + mutex_lock(&udc_lock); + list_del(&udc->list); + mutex_unlock(&udc_lock); + + kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE); + flush_work(&gadget->work); + device_del(&gadget->dev); + ida_free(&gadget_id_numbers, gadget->id_number); + cancel_work_sync(&udc->vbus_work); + device_unregister(&udc->dev); +} +EXPORT_SYMBOL_GPL(usb_del_gadget); + +/** + * 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) +{ + usb_del_gadget(gadget); + usb_put_gadget(gadget); +} +EXPORT_SYMBOL_GPL(usb_del_gadget_udc); + +/* ------------------------------------------------------------------------- */ + +static int gadget_match_driver(struct device *dev, struct device_driver *drv) +{ + struct usb_gadget *gadget = dev_to_usb_gadget(dev); + struct usb_udc *udc = gadget->udc; + struct usb_gadget_driver *driver = container_of(drv, + struct usb_gadget_driver, driver); + + /* If the driver specifies a udc_name, it must match the UDC's name */ + if (driver->udc_name && + strcmp(driver->udc_name, dev_name(&udc->dev)) != 0) + return 0; + + /* If the driver is already bound to a gadget, it doesn't match */ + if (driver->is_bound) + return 0; + + /* Otherwise any gadget driver matches any UDC */ + return 1; +} + +static int gadget_bind_driver(struct device *dev) +{ + struct usb_gadget *gadget = dev_to_usb_gadget(dev); + struct usb_udc *udc = gadget->udc; + struct usb_gadget_driver *driver = container_of(dev->driver, + struct usb_gadget_driver, driver); + int ret = 0; + + mutex_lock(&udc_lock); + if (driver->is_bound) { + mutex_unlock(&udc_lock); + return -ENXIO; /* Driver binds to only one gadget */ + } + driver->is_bound = true; + udc->driver = driver; + mutex_unlock(&udc_lock); + + dev_dbg(&udc->dev, "binding gadget driver [%s]\n", driver->function); + + usb_gadget_udc_set_speed(udc, driver->max_speed); + + ret = driver->bind(udc->gadget, driver); + if (ret) + goto err_bind; + + mutex_lock(&udc->connect_lock); + ret = usb_gadget_udc_start_locked(udc); + if (ret) { + mutex_unlock(&udc->connect_lock); + goto err_start; + } + usb_gadget_enable_async_callbacks(udc); + udc->allow_connect = true; + usb_udc_connect_control_locked(udc); + mutex_unlock(&udc->connect_lock); + + kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE); + return 0; + + err_start: + driver->unbind(udc->gadget); + + err_bind: + if (ret != -EISNAM) + dev_err(&udc->dev, "failed to start %s: %d\n", + driver->function, ret); + + mutex_lock(&udc_lock); + udc->driver = NULL; + driver->is_bound = false; + mutex_unlock(&udc_lock); + + return ret; +} + +static void gadget_unbind_driver(struct device *dev) +{ + struct usb_gadget *gadget = dev_to_usb_gadget(dev); + struct usb_udc *udc = gadget->udc; + struct usb_gadget_driver *driver = udc->driver; + + dev_dbg(&udc->dev, "unbinding gadget driver [%s]\n", driver->function); + + udc->allow_connect = false; + cancel_work_sync(&udc->vbus_work); + mutex_lock(&udc->connect_lock); + usb_gadget_disconnect_locked(gadget); + usb_gadget_disable_async_callbacks(udc); + if (gadget->irq) + synchronize_irq(gadget->irq); + mutex_unlock(&udc->connect_lock); + + udc->driver->unbind(gadget); + + mutex_lock(&udc->connect_lock); + usb_gadget_udc_stop_locked(udc); + mutex_unlock(&udc->connect_lock); + + mutex_lock(&udc_lock); + driver->is_bound = false; + udc->driver = NULL; + mutex_unlock(&udc_lock); + + kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE); +} + +/* ------------------------------------------------------------------------- */ + +int usb_gadget_register_driver_owner(struct usb_gadget_driver *driver, + struct module *owner, const char *mod_name) +{ + int ret; + + if (!driver || !driver->bind || !driver->setup) + return -EINVAL; + + driver->driver.bus = &gadget_bus_type; + driver->driver.owner = owner; + driver->driver.mod_name = mod_name; + ret = driver_register(&driver->driver); + if (ret) { + pr_warn("%s: driver registration failed: %d\n", + driver->function, ret); + return ret; + } + + mutex_lock(&udc_lock); + if (!driver->is_bound) { + if (driver->match_existing_only) { + pr_warn("%s: couldn't find an available UDC or it's busy\n", + driver->function); + ret = -EBUSY; + } else { + pr_info("%s: couldn't find an available UDC\n", + driver->function); + ret = 0; + } + } + mutex_unlock(&udc_lock); + + if (ret) + driver_unregister(&driver->driver); + return ret; +} +EXPORT_SYMBOL_GPL(usb_gadget_register_driver_owner); + +int usb_gadget_unregister_driver(struct usb_gadget_driver *driver) +{ + if (!driver || !driver->unbind) + return -EINVAL; + + driver_unregister(&driver->driver); + return 0; +} +EXPORT_SYMBOL_GPL(usb_gadget_unregister_driver); + +/* ------------------------------------------------------------------------- */ + +static ssize_t 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_WO(srp); + +static ssize_t soft_connect_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); + ssize_t ret; + + device_lock(&udc->gadget->dev); + if (!udc->driver) { + dev_err(dev, "soft-connect without a gadget driver\n"); + ret = -EOPNOTSUPP; + goto out; + } + + if (sysfs_streq(buf, "connect")) { + mutex_lock(&udc->connect_lock); + usb_gadget_udc_start_locked(udc); + usb_gadget_connect_locked(udc->gadget); + mutex_unlock(&udc->connect_lock); + } else if (sysfs_streq(buf, "disconnect")) { + mutex_lock(&udc->connect_lock); + usb_gadget_disconnect_locked(udc->gadget); + usb_gadget_udc_stop_locked(udc); + mutex_unlock(&udc->connect_lock); + } else { + dev_err(dev, "unsupported command '%s'\n", buf); + ret = -EINVAL; + goto out; + } + + ret = n; +out: + device_unlock(&udc->gadget->dev); + return ret; +} +static DEVICE_ATTR_WO(soft_connect); + +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); + +static ssize_t function_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct usb_udc *udc = container_of(dev, struct usb_udc, dev); + struct usb_gadget_driver *drv; + int rc = 0; + + mutex_lock(&udc_lock); + drv = udc->driver; + if (drv && drv->function) + rc = scnprintf(buf, PAGE_SIZE, "%s\n", drv->function); + mutex_unlock(&udc_lock); + return rc; +} +static DEVICE_ATTR_RO(function); + +#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 scnprintf(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 scnprintf(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 USB_UDC_ATTR(is_selfpowered); + +static struct attribute *usb_udc_attrs[] = { + &dev_attr_srp.attr, + &dev_attr_soft_connect.attr, + &dev_attr_state.attr, + &dev_attr_function.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, + &dev_attr_is_selfpowered.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; + } + + mutex_lock(&udc_lock); + if (udc->driver) + ret = add_uevent_var(env, "USB_UDC_DRIVER=%s", + udc->driver->function); + mutex_unlock(&udc_lock); + if (ret) { + dev_err(dev, "failed to add uevent USB_UDC_DRIVER\n"); + return ret; + } + + return 0; +} + +static struct bus_type gadget_bus_type = { + .name = "gadget", + .probe = gadget_bind_driver, + .remove = gadget_unbind_driver, + .match = gadget_match_driver, +}; + +static int __init usb_udc_init(void) +{ + int rc; + + 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; + + rc = bus_register(&gadget_bus_type); + if (rc) + class_destroy(udc_class); + return rc; +} +subsys_initcall(usb_udc_init); + +static void __exit usb_udc_exit(void) +{ + bus_unregister(&gadget_bus_type); + class_destroy(udc_class); +} +module_exit(usb_udc_exit); + +MODULE_DESCRIPTION("UDC Framework"); +MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>"); +MODULE_LICENSE("GPL v2"); |