diff options
Diffstat (limited to 'drivers/usb/gadget/udc/core.c')
| -rw-r--r-- | drivers/usb/gadget/udc/core.c | 903 |
1 files changed, 633 insertions, 270 deletions
diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c index e6f04eee95c4..8dbe79bdc0f9 100644 --- a/drivers/usb/gadget/udc/core.c +++ b/drivers/usb/gadget/udc/core.c @@ -1,26 +1,18 @@ -/** +// SPDX-License-Identifier: GPL-2.0 +/* * udc.c - Core UDC Framework * * Copyright (C) 2010 Texas Instruments * Author: Felipe Balbi <balbi@ti.com> - * - * This program is free software: you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 of - * the License as published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program. If not, see <http://www.gnu.org/licenses/>. */ +#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> @@ -32,14 +24,28 @@ #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; + * @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. @@ -50,15 +56,17 @@ struct usb_udc { 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 const struct class udc_class; static LIST_HEAD(udc_list); -static LIST_HEAD(gadget_driver_pending_list); -static DEFINE_MUTEX(udc_lock); -static int udc_bind_to_driver(struct usb_udc *udc, - struct usb_gadget_driver *driver); +/* Protects udc_list, udc->driver, driver->is_bound, and related calls */ +static DEFINE_MUTEX(udc_lock); /* ------------------------------------------------------------------------- */ @@ -96,7 +104,9 @@ EXPORT_SYMBOL_GPL(usb_ep_set_maxpacket_limit); * 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 master".) + * USB, "in" means "towards the USB host".) + * + * This routine may be called in an atomic (interrupt) context. * * returns zero, or a negative error code. */ @@ -107,6 +117,15 @@ int usb_ep_enable(struct usb_ep *ep) if (ep->enabled) goto out; + /* UDC drivers can't handle endpoints with maxpacket size 0 */ + if (!ep->desc || usb_endpoint_maxp(ep->desc) == 0) { + WARN_ONCE(1, "%s: ep%d (%s) has %s\n", __func__, ep->address, ep->name, + (!ep->desc) ? "NULL descriptor" : "maxpacket 0"); + + ret = -EINVAL; + goto out; + } + ret = ep->ops->enable(ep, ep->desc); if (ret) goto out; @@ -130,6 +149,8 @@ EXPORT_SYMBOL_GPL(usb_ep_enable); * 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) @@ -173,6 +194,9 @@ struct usb_request *usb_ep_alloc_request(struct usb_ep *ep, req = ep->ops->alloc_request(ep, gfp_flags); + if (req) + req->ep = ep; + trace_usb_ep_alloc_request(ep, req, req ? 0 : -ENOMEM); return req; @@ -191,8 +215,8 @@ EXPORT_SYMBOL_GPL(usb_ep_alloc_request); void usb_ep_free_request(struct usb_ep *ep, struct usb_request *req) { - ep->ops->free_request(ep, req); trace_usb_ep_free_request(ep, req, 0); + ep->ops->free_request(ep, req); } EXPORT_SYMBOL_GPL(usb_ep_free_request); @@ -249,16 +273,29 @@ EXPORT_SYMBOL_GPL(usb_ep_free_request); * 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)) { + if (!ep->enabled && ep->address) { + pr_debug("USB gadget: queue request to disabled ep 0x%x (%s)\n", + ep->address, ep->name); ret = -ESHUTDOWN; goto out; } @@ -277,15 +314,17 @@ EXPORT_SYMBOL_GPL(usb_ep_queue); * @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 its - * completion routine is called (with status -ECONNRESET); else a negative - * error code is returned. This is guaranteed to happen before the call to - * usb_ep_dequeue() returns. + * 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) { @@ -313,6 +352,8 @@ EXPORT_SYMBOL_GPL(usb_ep_dequeue); * 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 @@ -338,6 +379,8 @@ EXPORT_SYMBOL_GPL(usb_ep_set_halt); * 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), @@ -362,6 +405,8 @@ EXPORT_SYMBOL_GPL(usb_ep_clear_halt); * 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) @@ -390,6 +435,8 @@ EXPORT_SYMBOL_GPL(usb_ep_set_wedge); * 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. @@ -417,6 +464,8 @@ EXPORT_SYMBOL_GPL(usb_ep_fifo_status); * 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) { @@ -480,6 +529,33 @@ out: EXPORT_SYMBOL_GPL(usb_gadget_wakeup); /** + * 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) +{ + int ret = 0; + + if (!gadget->ops->set_remote_wakeup) { + ret = -EOPNOTSUPP; + goto out; + } + + ret = gadget->ops->set_remote_wakeup(gadget, set); + +out: + trace_usb_gadget_set_remote_wakeup(gadget, ret); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_gadget_set_remote_wakeup); + +/** * usb_gadget_set_selfpowered - sets the device selfpowered feature. * @gadget:the device being declared as self-powered * @@ -626,18 +702,8 @@ out: } EXPORT_SYMBOL_GPL(usb_gadget_vbus_disconnect); -/** - * 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). This pullup is always enabled unless - * usb_gadget_disconnect() has been used to disable it. - * - * Returns zero on success, else negative errno. - */ -int usb_gadget_connect(struct usb_gadget *gadget) +static int usb_gadget_connect_locked(struct usb_gadget *gadget) + __must_hold(&gadget->udc->connect_lock) { int ret = 0; @@ -646,10 +712,12 @@ int usb_gadget_connect(struct usb_gadget *gadget) goto out; } - if (gadget->deactivated) { + if (gadget->deactivated || !gadget->udc->allow_connect || !gadget->udc->started) { /* - * If gadget is deactivated we only save new state. - * Gadget will be connected automatically after activation. + * 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; @@ -664,19 +732,31 @@ out: return ret; } -EXPORT_SYMBOL_GPL(usb_gadget_connect); /** - * usb_gadget_disconnect - software-controlled disconnect from USB host - * @gadget:the peripheral being disconnected + * usb_gadget_connect - software-controlled connect to USB host + * @gadget:the peripheral being connected * - * 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. + * 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_disconnect(struct usb_gadget *gadget) +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; @@ -685,7 +765,10 @@ int usb_gadget_disconnect(struct usb_gadget *gadget) goto out; } - if (gadget->deactivated) { + 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. @@ -698,11 +781,40 @@ int usb_gadget_disconnect(struct usb_gadget *gadget) 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); /** @@ -714,19 +826,23 @@ EXPORT_SYMBOL_GPL(usb_gadget_disconnect); * 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 out; + goto unlock; if (gadget->connected) { - ret = usb_gadget_disconnect(gadget); + ret = usb_gadget_disconnect_locked(gadget); if (ret) - goto out; + goto unlock; /* * If gadget was being connected before deactivation, we want @@ -736,7 +852,8 @@ int usb_gadget_deactivate(struct usb_gadget *gadget) } gadget->deactivated = true; -out: +unlock: + mutex_unlock(&gadget->udc->connect_lock); trace_usb_gadget_deactivate(gadget, ret); return ret; @@ -750,14 +867,17 @@ EXPORT_SYMBOL_GPL(usb_gadget_deactivate); * 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 out; + goto unlock; gadget->deactivated = false; @@ -766,9 +886,10 @@ int usb_gadget_activate(struct usb_gadget *gadget) * while it was being deactivated, we call usb_gadget_connect(). */ if (gadget->connected) - ret = usb_gadget_connect(gadget); + ret = usb_gadget_connect_locked(gadget); -out: +unlock: + mutex_unlock(&gadget->udc->connect_lock); trace_usb_gadget_activate(gadget, ret); return ret; @@ -785,6 +906,11 @@ int usb_gadget_map_request_by_dev(struct device *dev, if (req->length == 0) return 0; + if (req->sg_was_mapped) { + req->num_mapped_sgs = req->num_sgs; + return 0; + } + if (req->num_sgs) { int mapped; @@ -812,6 +938,8 @@ int usb_gadget_map_request_by_dev(struct device *dev, dev_err(dev, "failed to map buffer\n"); return -EFAULT; } + + req->dma_mapped = 1; } return 0; @@ -828,7 +956,7 @@ 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) + if (req->length == 0 || req->sg_was_mapped) return; if (req->num_mapped_sgs) { @@ -836,9 +964,10 @@ void usb_gadget_unmap_request_by_dev(struct device *dev, is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE); req->num_mapped_sgs = 0; - } else { + } 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); @@ -856,7 +985,8 @@ EXPORT_SYMBOL_GPL(usb_gadget_unmap_request); /** * usb_gadget_giveback_request - give the request back to the gadget layer - * Context: in_interrupt() + * @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. @@ -909,7 +1039,7 @@ int usb_gadget_ep_match_desc(struct usb_gadget *gadget, return 0; type = usb_endpoint_type(desc); - max = 0x7ff & usb_endpoint_maxp(desc); + max = usb_endpoint_maxp(desc); if (usb_endpoint_dir_in(desc) && !ep->caps.dir_in) return 0; @@ -920,7 +1050,7 @@ int usb_gadget_ep_match_desc(struct usb_gadget *gadget, return 0; /* "high bandwidth" works only at high speed */ - if (!gadget_is_dualspeed(gadget) && usb_endpoint_maxp(desc) & (3<<11)) + if (!gadget_is_dualspeed(gadget) && usb_endpoint_maxp_mult(desc) > 1) return 0; switch (type) { @@ -963,6 +1093,25 @@ int usb_gadget_ep_match_desc(struct usb_gadget *gadget, } 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) @@ -977,19 +1126,35 @@ static void usb_gadget_state_work(struct work_struct *work) void usb_gadget_set_state(struct usb_gadget *gadget, enum usb_device_state state) { + unsigned long flags; + + spin_lock_irqsave(&gadget->state_lock, flags); gadget->state = state; - schedule_work(&gadget->work); + if (!gadget->teardown) + schedule_work(&gadget->work); + spin_unlock_irqrestore(&gadget->state_lock, flags); + trace_usb_gadget_set_state(gadget, 0); } EXPORT_SYMBOL_GPL(usb_gadget_set_state); /* ------------------------------------------------------------------------- */ -static void usb_udc_connect_control(struct usb_udc *udc) +/* Acquire connect_lock before calling this function. */ +static int usb_udc_connect_control_locked(struct usb_udc *udc) __must_hold(&udc->connect_lock) { if (udc->vbus) - usb_gadget_connect(udc->gadget); + return usb_gadget_connect_locked(udc->gadget); else - usb_gadget_disconnect(udc->gadget); + return 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); } /** @@ -1000,6 +1165,14 @@ static void usb_udc_connect_control(struct usb_udc *udc) * * 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) { @@ -1007,7 +1180,7 @@ void usb_udc_vbus_handler(struct usb_gadget *gadget, bool status) if (udc) { udc->vbus = status; - usb_udc_connect_control(udc); + schedule_work(&udc->vbus_work); } } EXPORT_SYMBOL_GPL(usb_udc_vbus_handler); @@ -1030,7 +1203,7 @@ void usb_gadget_udc_reset(struct usb_gadget *gadget, EXPORT_SYMBOL_GPL(usb_gadget_udc_reset); /** - * usb_gadget_udc_start - tells usb device controller to start up + * 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 @@ -1041,16 +1214,29 @@ EXPORT_SYMBOL_GPL(usb_gadget_udc_reset); * 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(struct usb_udc *udc) +static inline int usb_gadget_udc_start_locked(struct usb_udc *udc) + __must_hold(&udc->connect_lock) { - return udc->gadget->ops->udc_start(udc->gadget, udc->driver); + 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 - 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 + * 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. @@ -1058,10 +1244,19 @@ static inline int usb_gadget_udc_start(struct usb_udc *udc) * 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(struct usb_udc *udc) +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; } /** @@ -1077,8 +1272,65 @@ static inline void usb_gadget_udc_stop(struct usb_udc *udc) static inline void usb_gadget_udc_set_speed(struct usb_udc *udc, enum usb_device_speed speed) { - if (udc->gadget->ops->udc_set_speed) - udc->gadget->ops->udc_set_speed(udc->gadget, 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); } /** @@ -1104,103 +1356,134 @@ static void usb_udc_nop_release(struct device *dev) dev_vdbg(dev, "%s\n", __func__); } -/* should be called with udc_lock held */ -static int check_pending_gadget_drivers(struct usb_udc *udc) +/** + * 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)) { - struct usb_gadget_driver *driver; - int ret = 0; + spin_lock_init(&gadget->state_lock); + gadget->teardown = false; + INIT_WORK(&gadget->work, usb_gadget_state_work); + gadget->dev.parent = parent; - list_for_each_entry(driver, &gadget_driver_pending_list, pending) - if (!driver->udc_name || strcmp(driver->udc_name, - dev_name(&udc->dev)) == 0) { - ret = udc_bind_to_driver(udc, driver); - if (ret != -EPROBE_DEFER) - list_del(&driver->pending); - break; - } + if (release) + gadget->dev.release = release; + else + gadget->dev.release = usb_udc_nop_release; - return ret; + device_initialize(&gadget->dev); + gadget->dev.bus = &gadget_bus_type; } +EXPORT_SYMBOL_GPL(usb_initialize_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. + * usb_add_gadget - adds a new gadget to the udc class driver list * @gadget: the gadget to be added to the list. - * @release: a gadget release function. * * Returns zero on success, negative errno otherwise. + * Does not do a final usb_put_gadget() if an error occurs. */ -int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget, - void (*release)(struct device *dev)) +int usb_add_gadget(struct usb_gadget *gadget) { struct usb_udc *udc; int ret = -ENOMEM; udc = kzalloc(sizeof(*udc), GFP_KERNEL); if (!udc) - goto err1; - - dev_set_name(&gadget->dev, "gadget"); - INIT_WORK(&gadget->work, usb_gadget_state_work); - gadget->dev.parent = parent; - - if (release) - gadget->dev.release = release; - else - gadget->dev.release = usb_udc_nop_release; - - ret = device_register(&gadget->dev); - if (ret) - goto err2; + goto error; device_initialize(&udc->dev); udc->dev.release = usb_udc_release; - udc->dev.class = udc_class; + udc->dev.class = &udc_class; udc->dev.groups = usb_udc_attr_groups; - udc->dev.parent = parent; - ret = dev_set_name(&udc->dev, "%s", kobject_name(&parent->kobj)); + udc->dev.parent = gadget->dev.parent; + ret = dev_set_name(&udc->dev, "%s", + kobject_name(&gadget->dev.parent->kobj)); if (ret) - goto err3; + 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 err4; + goto err_unlist_udc; usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED); udc->vbus = true; - /* pick up one of pending gadget drivers */ - ret = check_pending_gadget_drivers(udc); + 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 err5; + goto err_free_id; - mutex_unlock(&udc_lock); + ret = sysfs_create_link(&udc->dev.kobj, + &gadget->dev.kobj, "gadget"); + if (ret) + goto err_del_gadget; return 0; -err5: + err_del_gadget: + device_del(&gadget->dev); + + err_free_id: + ida_free(&gadget_id_numbers, gadget->id_number); + + err_del_udc: + flush_work(&gadget->work); device_del(&udc->dev); -err4: + err_unlist_udc: + mutex_lock(&udc_lock); list_del(&udc->list); mutex_unlock(&udc_lock); -err3: + err_put_udc: put_device(&udc->dev); - device_del(&gadget->dev); -err2: - put_device(&gadget->dev); - kfree(udc); + 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; -err1: + 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); @@ -1249,33 +1532,17 @@ int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget) } 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); - - kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE); - - usb_gadget_disconnect(udc->gadget); - udc->driver->disconnect(udc->gadget); - udc->driver->unbind(udc->gadget); - usb_gadget_udc_stop(udc); - - udc->driver = NULL; - udc->dev.driver = NULL; - udc->gadget->dev.driver = NULL; -} - /** - * usb_del_gadget_udc - deletes @udc from udc_list - * @gadget: the gadget to be removed. + * usb_del_gadget - deletes a gadget and unregisters its udc + * @gadget: the gadget to be deleted. * - * This, will call usb_gadget_unregister_driver() if - * the @udc is still busy. + * This will unbind @gadget, if it is bound. + * It will not do a final usb_put_gadget(). */ -void usb_del_gadget_udc(struct usb_gadget *gadget) +void usb_del_gadget(struct usb_gadget *gadget) { struct usb_udc *udc = gadget->udc; + unsigned long flags; if (!udc) return; @@ -1284,144 +1551,211 @@ void usb_del_gadget_udc(struct usb_gadget *gadget) mutex_lock(&udc_lock); list_del(&udc->list); - - if (udc->driver) { - struct usb_gadget_driver *driver = udc->driver; - - usb_gadget_remove_driver(udc); - list_add(&driver->pending, &gadget_driver_pending_list); - } mutex_unlock(&udc_lock); kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE); + sysfs_remove_link(&udc->dev.kobj, "gadget"); + device_del(&gadget->dev); + /* + * Set the teardown flag before flushing the work to prevent new work + * from being scheduled while we are cleaning up. + */ + spin_lock_irqsave(&gadget->state_lock, flags); + gadget->teardown = true; + spin_unlock_irqrestore(&gadget->state_lock, flags); flush_work(&gadget->work); + ida_free(&gadget_id_numbers, gadget->id_number); + cancel_work_sync(&udc->vbus_work); device_unregister(&udc->dev); - device_unregister(&gadget->dev); - memset(&gadget->dev, 0x00, sizeof(gadget->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 udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *driver) +static int gadget_match_driver(struct device *dev, const struct device_driver *drv) { - int ret; + struct usb_gadget *gadget = dev_to_usb_gadget(dev); + struct usb_udc *udc = gadget->udc; + const 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; - dev_dbg(&udc->dev, "registering UDC driver [%s]\n", - driver->function); + /* 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; - udc->dev.driver = &driver->driver; - udc->gadget->dev.driver = &driver->driver; + mutex_unlock(&udc_lock); + + dev_dbg(&udc->dev, "binding gadget driver [%s]\n", driver->function); - if (driver->max_speed < udc->gadget->max_speed) - usb_gadget_udc_set_speed(udc, driver->max_speed); + usb_gadget_udc_set_speed(udc, driver->max_speed); ret = driver->bind(udc->gadget, driver); if (ret) - goto err1; - ret = usb_gadget_udc_start(udc); + goto err_bind; + + mutex_lock(&udc->connect_lock); + ret = usb_gadget_udc_start_locked(udc); if (ret) { - driver->unbind(udc->gadget); - goto err1; + mutex_unlock(&udc->connect_lock); + goto err_start; } - usb_udc_connect_control(udc); + usb_gadget_enable_async_callbacks(udc); + udc->allow_connect = true; + ret = usb_udc_connect_control_locked(udc); + if (ret) + goto err_connect_control; + + mutex_unlock(&udc->connect_lock); kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE); return 0; -err1: + + err_connect_control: + udc->allow_connect = false; + usb_gadget_disable_async_callbacks(udc); + if (gadget->irq) + synchronize_irq(gadget->irq); + usb_gadget_udc_stop_locked(udc); + mutex_unlock(&udc->connect_lock); + + err_start: + driver->unbind(udc->gadget); + + err_bind: if (ret != -EISNAM) dev_err(&udc->dev, "failed to start %s: %d\n", - udc->driver->function, ret); + driver->function, ret); + + mutex_lock(&udc_lock); udc->driver = NULL; - udc->dev.driver = NULL; - udc->gadget->dev.driver = NULL; + driver->is_bound = false; + mutex_unlock(&udc_lock); + return ret; } -int usb_gadget_probe_driver(struct usb_gadget_driver *driver) +static void gadget_unbind_driver(struct device *dev) { - struct usb_udc *udc = NULL; - int ret = -ENODEV; + struct usb_gadget *gadget = dev_to_usb_gadget(dev); + struct usb_udc *udc = gadget->udc; + struct usb_gadget_driver *driver = udc->driver; - if (!driver || !driver->bind || !driver->setup) - return -EINVAL; + dev_dbg(&udc->dev, "unbinding gadget driver [%s]\n", driver->function); - mutex_lock(&udc_lock); - if (driver->udc_name) { - list_for_each_entry(udc, &udc_list, list) { - ret = strcmp(driver->udc_name, dev_name(&udc->dev)); - if (!ret) - break; - } - if (ret) - ret = -ENODEV; - else if (udc->driver) - ret = -EBUSY; - else - goto found; - } else { - list_for_each_entry(udc, &udc_list, list) { - /* For now we take the first one */ - if (!udc->driver) - goto found; - } - } + 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); - if (!driver->match_existing_only) { - list_add_tail(&driver->pending, &gadget_driver_pending_list); - pr_info("udc-core: couldn't find an available UDC - added [%s] to list of pending drivers\n", - driver->function); - ret = 0; - } + 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); - return ret; -found: - ret = udc_bind_to_driver(udc, driver); - mutex_unlock(&udc_lock); - return ret; + + kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE); } -EXPORT_SYMBOL_GPL(usb_gadget_probe_driver); -int usb_gadget_unregister_driver(struct usb_gadget_driver *driver) +/* ------------------------------------------------------------------------- */ + +int usb_gadget_register_driver_owner(struct usb_gadget_driver *driver, + struct module *owner, const char *mod_name) { - struct usb_udc *udc = NULL; - int ret = -ENODEV; + int ret; - if (!driver || !driver->unbind) + if (!driver || !driver->bind || !driver->setup) return -EINVAL; + driver->driver.bus = &gadget_bus_type; + driver->driver.owner = owner; + driver->driver.mod_name = mod_name; + driver->driver.probe_type = PROBE_FORCE_SYNCHRONOUS; + ret = driver_register(&driver->driver); + if (ret) { + pr_warn("%s: driver registration failed: %d\n", + driver->function, ret); + return ret; + } + 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); - - /* Maybe there is someone waiting for this UDC? */ - check_pending_gadget_drivers(udc); - /* - * For now we ignore bind errors as probably it's - * not a valid reason to fail other's gadget unbind - */ + 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; - break; } } - - if (ret) { - list_del(&driver->pending); - 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 usb_udc_srp_store(struct device *dev, +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); @@ -1431,33 +1765,43 @@ static ssize_t usb_udc_srp_store(struct device *dev, return n; } -static DEVICE_ATTR(srp, S_IWUSR, NULL, usb_udc_srp_store); +static DEVICE_ATTR_WO(srp); -static ssize_t usb_udc_softconn_store(struct device *dev, +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"); - return -EOPNOTSUPP; + ret = -EOPNOTSUPP; + goto out; } if (sysfs_streq(buf, "connect")) { - usb_gadget_udc_start(udc); - usb_gadget_connect(udc->gadget); + 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")) { - usb_gadget_disconnect(udc->gadget); - udc->driver->disconnect(udc->gadget); - usb_gadget_udc_stop(udc); + 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); - return -EINVAL; + ret = -EINVAL; + goto out; } - return n; + ret = n; +out: + device_unlock(&udc->gadget->dev); + return ret; } -static DEVICE_ATTR(soft_connect, S_IWUSR, NULL, usb_udc_softconn_store); +static DEVICE_ATTR_WO(soft_connect); static ssize_t state_show(struct device *dev, struct device_attribute *attr, char *buf) @@ -1473,11 +1817,15 @@ 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 = udc->driver; + struct usb_gadget_driver *drv; + int rc = 0; - if (!drv || !drv->function) - return 0; - return scnprintf(buf, PAGE_SIZE, "%s\n", drv->function); + 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); @@ -1486,7 +1834,7 @@ ssize_t name##_show(struct device *dev, \ struct device_attribute *attr, char *buf) \ { \ struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \ - return snprintf(buf, PAGE_SIZE, "%s\n", \ + return scnprintf(buf, PAGE_SIZE, "%s\n", \ usb_speed_string(udc->gadget->param)); \ } \ static DEVICE_ATTR_RO(name) @@ -1501,7 +1849,7 @@ ssize_t name##_show(struct device *dev, \ struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \ struct usb_gadget *gadget = udc->gadget; \ \ - return snprintf(buf, PAGE_SIZE, "%d\n", gadget->name); \ + return scnprintf(buf, PAGE_SIZE, "%d\n", gadget->name); \ } \ static DEVICE_ATTR_RO(name) @@ -1538,9 +1886,9 @@ static const struct attribute_group *usb_udc_attr_groups[] = { NULL, }; -static int usb_udc_uevent(struct device *dev, struct kobj_uevent_env *env) +static int usb_udc_uevent(const struct device *dev, struct kobj_uevent_env *env) { - struct usb_udc *udc = container_of(dev, struct usb_udc, dev); + const 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); @@ -1549,35 +1897,50 @@ static int usb_udc_uevent(struct device *dev, struct kobj_uevent_env *env) return ret; } - if (udc->driver) { + mutex_lock(&udc_lock); + if (udc->driver) ret = add_uevent_var(env, "USB_UDC_DRIVER=%s", udc->driver->function); - if (ret) { - dev_err(dev, "failed to add uevent USB_UDC_DRIVER\n"); - return ret; - } + mutex_unlock(&udc_lock); + if (ret) { + dev_err(dev, "failed to add uevent USB_UDC_DRIVER\n"); + return ret; } return 0; } +static const struct class udc_class = { + .name = "udc", + .dev_uevent = usb_udc_uevent, +}; + +static const 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) { - 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); - } + int rc; - udc_class->dev_uevent = usb_udc_uevent; - return 0; + rc = class_register(&udc_class); + if (rc) + return rc; + + rc = bus_register(&gadget_bus_type); + if (rc) + class_unregister(&udc_class); + return rc; } subsys_initcall(usb_udc_init); static void __exit usb_udc_exit(void) { - class_destroy(udc_class); + bus_unregister(&gadget_bus_type); + class_unregister(&udc_class); } module_exit(usb_udc_exit); |