2 * udc.c - Core UDC Framework
4 * Copyright (C) 2010 Texas Instruments
5 * Author: Felipe Balbi <balbi@ti.com>
7 * This program is free software: you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 of
9 * the License as published by the Free Software Foundation.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/device.h>
23 #include <linux/list.h>
24 #include <linux/err.h>
25 #include <linux/dma-mapping.h>
26 #include <linux/workqueue.h>
28 #include <linux/usb/ch9.h>
29 #include <linux/usb/gadget.h>
30 #include <linux/usb.h>
33 * struct usb_udc - describes one usb device controller
34 * @driver - the gadget driver pointer. For use by the class code
35 * @dev - the child device to the actual controller
36 * @gadget - the gadget. For use by the class code
37 * @list - for use by the udc class driver
38 * @vbus - for udcs who care about vbus status, this value is real vbus status;
39 * for udcs who do not care about vbus status, this value is always true
41 * This represents the internal data structure which is used by the UDC-class
42 * to hold information about udc driver and gadget together.
45 struct usb_gadget_driver *driver;
46 struct usb_gadget *gadget;
48 struct list_head list;
52 static struct class *udc_class;
53 static LIST_HEAD(udc_list);
54 static LIST_HEAD(gadget_driver_pending_list);
55 static DEFINE_MUTEX(udc_lock);
57 static int udc_bind_to_driver(struct usb_udc *udc,
58 struct usb_gadget_driver *driver);
60 /* ------------------------------------------------------------------------- */
64 int usb_gadget_map_request(struct usb_gadget *gadget,
65 struct usb_request *req, int is_in)
67 struct device *dev = gadget->dev.parent;
75 mapped = dma_map_sg(dev, req->sg, req->num_sgs,
76 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
78 dev_err(&gadget->dev, "failed to map SGs\n");
82 req->num_mapped_sgs = mapped;
84 req->dma = dma_map_single(dev, req->buf, req->length,
85 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
87 if (dma_mapping_error(dev, req->dma)) {
88 dev_err(dev, "failed to map buffer\n");
95 EXPORT_SYMBOL_GPL(usb_gadget_map_request);
97 void usb_gadget_unmap_request(struct usb_gadget *gadget,
98 struct usb_request *req, int is_in)
100 if (req->length == 0)
103 if (req->num_mapped_sgs) {
104 dma_unmap_sg(gadget->dev.parent, req->sg, req->num_mapped_sgs,
105 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
107 req->num_mapped_sgs = 0;
109 dma_unmap_single(gadget->dev.parent, req->dma, req->length,
110 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
113 EXPORT_SYMBOL_GPL(usb_gadget_unmap_request);
115 #endif /* CONFIG_HAS_DMA */
117 /* ------------------------------------------------------------------------- */
120 * usb_gadget_giveback_request - give the request back to the gadget layer
121 * Context: in_interrupt()
123 * This is called by device controller drivers in order to return the
124 * completed request back to the gadget layer.
126 void usb_gadget_giveback_request(struct usb_ep *ep,
127 struct usb_request *req)
129 if (likely(req->status == 0))
130 usb_led_activity(USB_LED_EVENT_GADGET);
132 req->complete(ep, req);
134 EXPORT_SYMBOL_GPL(usb_gadget_giveback_request);
136 /* ------------------------------------------------------------------------- */
139 * gadget_find_ep_by_name - returns ep whose name is the same as sting passed
140 * in second parameter or NULL if searched endpoint not found
141 * @g: controller to check for quirk
142 * @name: name of searched endpoint
144 struct usb_ep *gadget_find_ep_by_name(struct usb_gadget *g, const char *name)
148 gadget_for_each_ep(ep, g) {
149 if (!strcmp(ep->name, name))
155 EXPORT_SYMBOL_GPL(gadget_find_ep_by_name);
157 /* ------------------------------------------------------------------------- */
159 int usb_gadget_ep_match_desc(struct usb_gadget *gadget,
160 struct usb_ep *ep, struct usb_endpoint_descriptor *desc,
161 struct usb_ss_ep_comp_descriptor *ep_comp)
165 int num_req_streams = 0;
167 /* endpoint already claimed? */
171 type = usb_endpoint_type(desc);
172 max = 0x7ff & usb_endpoint_maxp(desc);
174 if (usb_endpoint_dir_in(desc) && !ep->caps.dir_in)
176 if (usb_endpoint_dir_out(desc) && !ep->caps.dir_out)
179 if (max > ep->maxpacket_limit)
182 /* "high bandwidth" works only at high speed */
183 if (!gadget_is_dualspeed(gadget) && usb_endpoint_maxp(desc) & (3<<11))
187 case USB_ENDPOINT_XFER_CONTROL:
188 /* only support ep0 for portable CONTROL traffic */
190 case USB_ENDPOINT_XFER_ISOC:
191 if (!ep->caps.type_iso)
193 /* ISO: limit 1023 bytes full speed, 1024 high/super speed */
194 if (!gadget_is_dualspeed(gadget) && max > 1023)
197 case USB_ENDPOINT_XFER_BULK:
198 if (!ep->caps.type_bulk)
200 if (ep_comp && gadget_is_superspeed(gadget)) {
201 /* Get the number of required streams from the
202 * EP companion descriptor and see if the EP
205 num_req_streams = ep_comp->bmAttributes & 0x1f;
206 if (num_req_streams > ep->max_streams)
210 case USB_ENDPOINT_XFER_INT:
211 /* Bulk endpoints handle interrupt transfers,
212 * except the toggle-quirky iso-synch kind
214 if (!ep->caps.type_int && !ep->caps.type_bulk)
216 /* INT: limit 64 bytes full speed, 1024 high/super speed */
217 if (!gadget_is_dualspeed(gadget) && max > 64)
224 EXPORT_SYMBOL_GPL(usb_gadget_ep_match_desc);
226 /* ------------------------------------------------------------------------- */
228 static void usb_gadget_state_work(struct work_struct *work)
230 struct usb_gadget *gadget = work_to_gadget(work);
231 struct usb_udc *udc = gadget->udc;
234 sysfs_notify(&udc->dev.kobj, NULL, "state");
237 void usb_gadget_set_state(struct usb_gadget *gadget,
238 enum usb_device_state state)
240 gadget->state = state;
241 schedule_work(&gadget->work);
243 EXPORT_SYMBOL_GPL(usb_gadget_set_state);
245 /* ------------------------------------------------------------------------- */
247 static void usb_udc_connect_control(struct usb_udc *udc)
250 usb_gadget_connect(udc->gadget);
252 usb_gadget_disconnect(udc->gadget);
256 * usb_udc_vbus_handler - updates the udc core vbus status, and try to
257 * connect or disconnect gadget
258 * @gadget: The gadget which vbus change occurs
259 * @status: The vbus status
261 * The udc driver calls it when it wants to connect or disconnect gadget
262 * according to vbus status.
264 void usb_udc_vbus_handler(struct usb_gadget *gadget, bool status)
266 struct usb_udc *udc = gadget->udc;
270 usb_udc_connect_control(udc);
273 EXPORT_SYMBOL_GPL(usb_udc_vbus_handler);
276 * usb_gadget_udc_reset - notifies the udc core that bus reset occurs
277 * @gadget: The gadget which bus reset occurs
278 * @driver: The gadget driver we want to notify
280 * If the udc driver has bus reset handler, it needs to call this when the bus
281 * reset occurs, it notifies the gadget driver that the bus reset occurs as
282 * well as updates gadget state.
284 void usb_gadget_udc_reset(struct usb_gadget *gadget,
285 struct usb_gadget_driver *driver)
287 driver->reset(gadget);
288 usb_gadget_set_state(gadget, USB_STATE_DEFAULT);
290 EXPORT_SYMBOL_GPL(usb_gadget_udc_reset);
293 * usb_gadget_udc_start - tells usb device controller to start up
294 * @udc: The UDC to be started
296 * This call is issued by the UDC Class driver when it's about
297 * to register a gadget driver to the device controller, before
298 * calling gadget driver's bind() method.
300 * It allows the controller to be powered off until strictly
301 * necessary to have it powered on.
303 * Returns zero on success, else negative errno.
305 static inline int usb_gadget_udc_start(struct usb_udc *udc)
307 return udc->gadget->ops->udc_start(udc->gadget, udc->driver);
311 * usb_gadget_udc_stop - tells usb device controller we don't need it anymore
312 * @gadget: The device we want to stop activity
313 * @driver: The driver to unbind from @gadget
315 * This call is issued by the UDC Class driver after calling
316 * gadget driver's unbind() method.
318 * The details are implementation specific, but it can go as
319 * far as powering off UDC completely and disable its data
322 static inline void usb_gadget_udc_stop(struct usb_udc *udc)
324 udc->gadget->ops->udc_stop(udc->gadget);
328 * usb_udc_release - release the usb_udc struct
329 * @dev: the dev member within usb_udc
331 * This is called by driver's core in order to free memory once the last
332 * reference is released.
334 static void usb_udc_release(struct device *dev)
338 udc = container_of(dev, struct usb_udc, dev);
339 dev_dbg(dev, "releasing '%s'\n", dev_name(dev));
343 static const struct attribute_group *usb_udc_attr_groups[];
345 static void usb_udc_nop_release(struct device *dev)
347 dev_vdbg(dev, "%s\n", __func__);
351 * usb_add_gadget_udc_release - adds a new gadget to the udc class driver list
352 * @parent: the parent device to this udc. Usually the controller driver's
354 * @gadget: the gadget to be added to the list.
355 * @release: a gadget release function.
357 * Returns zero on success, negative errno otherwise.
359 int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
360 void (*release)(struct device *dev))
363 struct usb_gadget_driver *driver;
366 udc = kzalloc(sizeof(*udc), GFP_KERNEL);
370 dev_set_name(&gadget->dev, "gadget");
371 INIT_WORK(&gadget->work, usb_gadget_state_work);
372 gadget->dev.parent = parent;
374 #ifdef CONFIG_HAS_DMA
375 dma_set_coherent_mask(&gadget->dev, parent->coherent_dma_mask);
376 gadget->dev.dma_parms = parent->dma_parms;
377 gadget->dev.dma_mask = parent->dma_mask;
381 gadget->dev.release = release;
383 gadget->dev.release = usb_udc_nop_release;
385 ret = device_register(&gadget->dev);
389 device_initialize(&udc->dev);
390 udc->dev.release = usb_udc_release;
391 udc->dev.class = udc_class;
392 udc->dev.groups = usb_udc_attr_groups;
393 udc->dev.parent = parent;
394 ret = dev_set_name(&udc->dev, "%s", kobject_name(&parent->kobj));
398 udc->gadget = gadget;
401 mutex_lock(&udc_lock);
402 list_add_tail(&udc->list, &udc_list);
404 ret = device_add(&udc->dev);
408 usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED);
411 /* pick up one of pending gadget drivers */
412 list_for_each_entry(driver, &gadget_driver_pending_list, pending) {
413 if (!driver->udc_name || strcmp(driver->udc_name,
414 dev_name(&udc->dev)) == 0) {
415 ret = udc_bind_to_driver(udc, driver);
416 if (ret != -EPROBE_DEFER)
417 list_del(&driver->pending);
424 mutex_unlock(&udc_lock);
429 list_del(&udc->list);
430 mutex_unlock(&udc_lock);
433 put_device(&udc->dev);
434 device_del(&gadget->dev);
437 put_device(&gadget->dev);
443 EXPORT_SYMBOL_GPL(usb_add_gadget_udc_release);
446 * usb_get_gadget_udc_name - get the name of the first UDC controller
447 * This functions returns the name of the first UDC controller in the system.
448 * Please note that this interface is usefull only for legacy drivers which
449 * assume that there is only one UDC controller in the system and they need to
450 * get its name before initialization. There is no guarantee that the UDC
451 * of the returned name will be still available, when gadget driver registers
454 * Returns pointer to string with UDC controller name on success, NULL
455 * otherwise. Caller should kfree() returned string.
457 char *usb_get_gadget_udc_name(void)
462 /* For now we take the first available UDC */
463 mutex_lock(&udc_lock);
464 list_for_each_entry(udc, &udc_list, list) {
466 name = kstrdup(udc->gadget->name, GFP_KERNEL);
470 mutex_unlock(&udc_lock);
473 EXPORT_SYMBOL_GPL(usb_get_gadget_udc_name);
476 * usb_add_gadget_udc - adds a new gadget to the udc class driver list
477 * @parent: the parent device to this udc. Usually the controller
479 * @gadget: the gadget to be added to the list
481 * Returns zero on success, negative errno otherwise.
483 int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget)
485 return usb_add_gadget_udc_release(parent, gadget, NULL);
487 EXPORT_SYMBOL_GPL(usb_add_gadget_udc);
489 static void usb_gadget_remove_driver(struct usb_udc *udc)
491 dev_dbg(&udc->dev, "unregistering UDC driver [%s]\n",
492 udc->driver->function);
494 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
496 usb_gadget_disconnect(udc->gadget);
497 udc->driver->disconnect(udc->gadget);
498 udc->driver->unbind(udc->gadget);
499 usb_gadget_udc_stop(udc);
502 udc->dev.driver = NULL;
503 udc->gadget->dev.driver = NULL;
507 * usb_del_gadget_udc - deletes @udc from udc_list
508 * @gadget: the gadget to be removed.
510 * This, will call usb_gadget_unregister_driver() if
511 * the @udc is still busy.
513 void usb_del_gadget_udc(struct usb_gadget *gadget)
515 struct usb_udc *udc = gadget->udc;
520 dev_vdbg(gadget->dev.parent, "unregistering gadget\n");
522 mutex_lock(&udc_lock);
523 list_del(&udc->list);
526 struct usb_gadget_driver *driver = udc->driver;
528 usb_gadget_remove_driver(udc);
529 list_add(&driver->pending, &gadget_driver_pending_list);
531 mutex_unlock(&udc_lock);
533 kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE);
534 flush_work(&gadget->work);
535 device_unregister(&udc->dev);
536 device_unregister(&gadget->dev);
538 EXPORT_SYMBOL_GPL(usb_del_gadget_udc);
540 /* ------------------------------------------------------------------------- */
542 static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *driver)
546 dev_dbg(&udc->dev, "registering UDC driver [%s]\n",
549 udc->driver = driver;
550 udc->dev.driver = &driver->driver;
551 udc->gadget->dev.driver = &driver->driver;
553 ret = driver->bind(udc->gadget, driver);
556 ret = usb_gadget_udc_start(udc);
558 driver->unbind(udc->gadget);
561 usb_udc_connect_control(udc);
563 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
567 dev_err(&udc->dev, "failed to start %s: %d\n",
568 udc->driver->function, ret);
570 udc->dev.driver = NULL;
571 udc->gadget->dev.driver = NULL;
575 int usb_gadget_probe_driver(struct usb_gadget_driver *driver)
577 struct usb_udc *udc = NULL;
580 if (!driver || !driver->bind || !driver->setup)
583 mutex_lock(&udc_lock);
584 if (driver->udc_name) {
585 list_for_each_entry(udc, &udc_list, list) {
586 ret = strcmp(driver->udc_name, dev_name(&udc->dev));
590 if (!ret && !udc->driver)
593 list_for_each_entry(udc, &udc_list, list) {
594 /* For now we take the first one */
600 list_add_tail(&driver->pending, &gadget_driver_pending_list);
601 pr_info("udc-core: couldn't find an available UDC - added [%s] to list of pending drivers\n",
603 mutex_unlock(&udc_lock);
606 ret = udc_bind_to_driver(udc, driver);
607 mutex_unlock(&udc_lock);
610 EXPORT_SYMBOL_GPL(usb_gadget_probe_driver);
612 int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
614 struct usb_udc *udc = NULL;
617 if (!driver || !driver->unbind)
620 mutex_lock(&udc_lock);
621 list_for_each_entry(udc, &udc_list, list)
622 if (udc->driver == driver) {
623 usb_gadget_remove_driver(udc);
624 usb_gadget_set_state(udc->gadget,
625 USB_STATE_NOTATTACHED);
631 list_del(&driver->pending);
634 mutex_unlock(&udc_lock);
637 EXPORT_SYMBOL_GPL(usb_gadget_unregister_driver);
639 /* ------------------------------------------------------------------------- */
641 static ssize_t usb_udc_srp_store(struct device *dev,
642 struct device_attribute *attr, const char *buf, size_t n)
644 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
646 if (sysfs_streq(buf, "1"))
647 usb_gadget_wakeup(udc->gadget);
651 static DEVICE_ATTR(srp, S_IWUSR, NULL, usb_udc_srp_store);
653 static ssize_t usb_udc_softconn_store(struct device *dev,
654 struct device_attribute *attr, const char *buf, size_t n)
656 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
659 dev_err(dev, "soft-connect without a gadget driver\n");
663 if (sysfs_streq(buf, "connect")) {
664 usb_gadget_udc_start(udc);
665 usb_gadget_connect(udc->gadget);
666 } else if (sysfs_streq(buf, "disconnect")) {
667 usb_gadget_disconnect(udc->gadget);
668 udc->driver->disconnect(udc->gadget);
669 usb_gadget_udc_stop(udc);
671 dev_err(dev, "unsupported command '%s'\n", buf);
677 static DEVICE_ATTR(soft_connect, S_IWUSR, NULL, usb_udc_softconn_store);
679 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
682 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
683 struct usb_gadget *gadget = udc->gadget;
685 return sprintf(buf, "%s\n", usb_state_string(gadget->state));
687 static DEVICE_ATTR_RO(state);
689 #define USB_UDC_SPEED_ATTR(name, param) \
690 ssize_t name##_show(struct device *dev, \
691 struct device_attribute *attr, char *buf) \
693 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
694 return snprintf(buf, PAGE_SIZE, "%s\n", \
695 usb_speed_string(udc->gadget->param)); \
697 static DEVICE_ATTR_RO(name)
699 static USB_UDC_SPEED_ATTR(current_speed, speed);
700 static USB_UDC_SPEED_ATTR(maximum_speed, max_speed);
702 #define USB_UDC_ATTR(name) \
703 ssize_t name##_show(struct device *dev, \
704 struct device_attribute *attr, char *buf) \
706 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
707 struct usb_gadget *gadget = udc->gadget; \
709 return snprintf(buf, PAGE_SIZE, "%d\n", gadget->name); \
711 static DEVICE_ATTR_RO(name)
713 static USB_UDC_ATTR(is_otg);
714 static USB_UDC_ATTR(is_a_peripheral);
715 static USB_UDC_ATTR(b_hnp_enable);
716 static USB_UDC_ATTR(a_hnp_support);
717 static USB_UDC_ATTR(a_alt_hnp_support);
718 static USB_UDC_ATTR(is_selfpowered);
720 static struct attribute *usb_udc_attrs[] = {
722 &dev_attr_soft_connect.attr,
723 &dev_attr_state.attr,
724 &dev_attr_current_speed.attr,
725 &dev_attr_maximum_speed.attr,
727 &dev_attr_is_otg.attr,
728 &dev_attr_is_a_peripheral.attr,
729 &dev_attr_b_hnp_enable.attr,
730 &dev_attr_a_hnp_support.attr,
731 &dev_attr_a_alt_hnp_support.attr,
732 &dev_attr_is_selfpowered.attr,
736 static const struct attribute_group usb_udc_attr_group = {
737 .attrs = usb_udc_attrs,
740 static const struct attribute_group *usb_udc_attr_groups[] = {
745 static int usb_udc_uevent(struct device *dev, struct kobj_uevent_env *env)
747 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
750 ret = add_uevent_var(env, "USB_UDC_NAME=%s", udc->gadget->name);
752 dev_err(dev, "failed to add uevent USB_UDC_NAME\n");
757 ret = add_uevent_var(env, "USB_UDC_DRIVER=%s",
758 udc->driver->function);
760 dev_err(dev, "failed to add uevent USB_UDC_DRIVER\n");
768 static int __init usb_udc_init(void)
770 udc_class = class_create(THIS_MODULE, "udc");
771 if (IS_ERR(udc_class)) {
772 pr_err("failed to create udc class --> %ld\n",
774 return PTR_ERR(udc_class);
777 udc_class->dev_uevent = usb_udc_uevent;
780 subsys_initcall(usb_udc_init);
782 static void __exit usb_udc_exit(void)
784 class_destroy(udc_class);
786 module_exit(usb_udc_exit);
788 MODULE_DESCRIPTION("UDC Framework");
789 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
790 MODULE_LICENSE("GPL v2");