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
39 * This represents the internal data structure which is used by the UDC-class
40 * to hold information about udc driver and gadget together.
43 struct usb_gadget_driver *driver;
44 struct usb_gadget *gadget;
46 struct list_head list;
49 static struct class *udc_class;
50 static LIST_HEAD(udc_list);
51 static DEFINE_MUTEX(udc_lock);
53 /* ------------------------------------------------------------------------- */
57 int usb_gadget_map_request(struct usb_gadget *gadget,
58 struct usb_request *req, int is_in)
66 mapped = dma_map_sg(&gadget->dev, req->sg, req->num_sgs,
67 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
69 dev_err(&gadget->dev, "failed to map SGs\n");
73 req->num_mapped_sgs = mapped;
75 req->dma = dma_map_single(&gadget->dev, req->buf, req->length,
76 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
78 if (dma_mapping_error(&gadget->dev, req->dma)) {
79 dev_err(&gadget->dev, "failed to map buffer\n");
86 EXPORT_SYMBOL_GPL(usb_gadget_map_request);
88 void usb_gadget_unmap_request(struct usb_gadget *gadget,
89 struct usb_request *req, int is_in)
94 if (req->num_mapped_sgs) {
95 dma_unmap_sg(&gadget->dev, req->sg, req->num_mapped_sgs,
96 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
98 req->num_mapped_sgs = 0;
100 dma_unmap_single(&gadget->dev, req->dma, req->length,
101 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
104 EXPORT_SYMBOL_GPL(usb_gadget_unmap_request);
106 #endif /* CONFIG_HAS_DMA */
108 /* ------------------------------------------------------------------------- */
111 * usb_gadget_giveback_request - give the request back to the gadget layer
112 * Context: in_interrupt()
114 * This is called by device controller drivers in order to return the
115 * completed request back to the gadget layer.
117 void usb_gadget_giveback_request(struct usb_ep *ep,
118 struct usb_request *req)
120 if (likely(req->status == 0))
121 usb_led_activity(USB_LED_EVENT_GADGET);
123 req->complete(ep, req);
125 EXPORT_SYMBOL_GPL(usb_gadget_giveback_request);
127 /* ------------------------------------------------------------------------- */
129 static void usb_gadget_state_work(struct work_struct *work)
131 struct usb_gadget *gadget = work_to_gadget(work);
132 struct usb_udc *udc = NULL;
134 mutex_lock(&udc_lock);
135 list_for_each_entry(udc, &udc_list, list)
136 if (udc->gadget == gadget)
138 mutex_unlock(&udc_lock);
143 mutex_unlock(&udc_lock);
145 sysfs_notify(&udc->dev.kobj, NULL, "state");
148 void usb_gadget_set_state(struct usb_gadget *gadget,
149 enum usb_device_state state)
151 gadget->state = state;
152 schedule_work(&gadget->work);
154 EXPORT_SYMBOL_GPL(usb_gadget_set_state);
156 /* ------------------------------------------------------------------------- */
159 * usb_gadget_udc_reset - notifies the udc core that bus reset occurs
160 * @gadget: The gadget which bus reset occurs
161 * @driver: The gadget driver we want to notify
163 * If the udc driver has bus reset handler, it needs to call this when the bus
164 * reset occurs, it notifies the gadget driver that the bus reset occurs as
165 * well as updates gadget state.
167 void usb_gadget_udc_reset(struct usb_gadget *gadget,
168 struct usb_gadget_driver *driver)
170 driver->reset(gadget);
171 usb_gadget_set_state(gadget, USB_STATE_DEFAULT);
173 EXPORT_SYMBOL_GPL(usb_gadget_udc_reset);
176 * usb_gadget_udc_start - tells usb device controller to start up
177 * @udc: The UDC to be started
179 * This call is issued by the UDC Class driver when it's about
180 * to register a gadget driver to the device controller, before
181 * calling gadget driver's bind() method.
183 * It allows the controller to be powered off until strictly
184 * necessary to have it powered on.
186 * Returns zero on success, else negative errno.
188 static inline int usb_gadget_udc_start(struct usb_udc *udc)
190 return udc->gadget->ops->udc_start(udc->gadget, udc->driver);
194 * usb_gadget_udc_stop - tells usb device controller we don't need it anymore
195 * @gadget: The device we want to stop activity
196 * @driver: The driver to unbind from @gadget
198 * This call is issued by the UDC Class driver after calling
199 * gadget driver's unbind() method.
201 * The details are implementation specific, but it can go as
202 * far as powering off UDC completely and disable its data
205 static inline void usb_gadget_udc_stop(struct usb_udc *udc)
207 udc->gadget->ops->udc_stop(udc->gadget);
211 * usb_udc_release - release the usb_udc struct
212 * @dev: the dev member within usb_udc
214 * This is called by driver's core in order to free memory once the last
215 * reference is released.
217 static void usb_udc_release(struct device *dev)
221 udc = container_of(dev, struct usb_udc, dev);
222 dev_dbg(dev, "releasing '%s'\n", dev_name(dev));
226 static const struct attribute_group *usb_udc_attr_groups[];
228 static void usb_udc_nop_release(struct device *dev)
230 dev_vdbg(dev, "%s\n", __func__);
234 * usb_add_gadget_udc_release - adds a new gadget to the udc class driver list
235 * @parent: the parent device to this udc. Usually the controller driver's
237 * @gadget: the gadget to be added to the list.
238 * @release: a gadget release function.
240 * Returns zero on success, negative errno otherwise.
242 int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
243 void (*release)(struct device *dev))
248 udc = kzalloc(sizeof(*udc), GFP_KERNEL);
252 dev_set_name(&gadget->dev, "gadget");
253 INIT_WORK(&gadget->work, usb_gadget_state_work);
254 gadget->dev.parent = parent;
256 #ifdef CONFIG_HAS_DMA
257 dma_set_coherent_mask(&gadget->dev, parent->coherent_dma_mask);
258 gadget->dev.dma_parms = parent->dma_parms;
259 gadget->dev.dma_mask = parent->dma_mask;
263 gadget->dev.release = release;
265 gadget->dev.release = usb_udc_nop_release;
267 ret = device_register(&gadget->dev);
271 device_initialize(&udc->dev);
272 udc->dev.release = usb_udc_release;
273 udc->dev.class = udc_class;
274 udc->dev.groups = usb_udc_attr_groups;
275 udc->dev.parent = parent;
276 ret = dev_set_name(&udc->dev, "%s", kobject_name(&parent->kobj));
280 udc->gadget = gadget;
282 mutex_lock(&udc_lock);
283 list_add_tail(&udc->list, &udc_list);
285 ret = device_add(&udc->dev);
289 usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED);
291 mutex_unlock(&udc_lock);
296 list_del(&udc->list);
297 mutex_unlock(&udc_lock);
300 put_device(&udc->dev);
303 put_device(&gadget->dev);
309 EXPORT_SYMBOL_GPL(usb_add_gadget_udc_release);
312 * usb_add_gadget_udc - adds a new gadget to the udc class driver list
313 * @parent: the parent device to this udc. Usually the controller
315 * @gadget: the gadget to be added to the list
317 * Returns zero on success, negative errno otherwise.
319 int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget)
321 return usb_add_gadget_udc_release(parent, gadget, NULL);
323 EXPORT_SYMBOL_GPL(usb_add_gadget_udc);
325 static void usb_gadget_remove_driver(struct usb_udc *udc)
327 dev_dbg(&udc->dev, "unregistering UDC driver [%s]\n",
328 udc->driver->function);
330 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
332 usb_gadget_disconnect(udc->gadget);
333 udc->driver->disconnect(udc->gadget);
334 udc->driver->unbind(udc->gadget);
335 usb_gadget_udc_stop(udc);
338 udc->dev.driver = NULL;
339 udc->gadget->dev.driver = NULL;
343 * usb_del_gadget_udc - deletes @udc from udc_list
344 * @gadget: the gadget to be removed.
346 * This, will call usb_gadget_unregister_driver() if
347 * the @udc is still busy.
349 void usb_del_gadget_udc(struct usb_gadget *gadget)
351 struct usb_udc *udc = NULL;
353 mutex_lock(&udc_lock);
354 list_for_each_entry(udc, &udc_list, list)
355 if (udc->gadget == gadget)
358 dev_err(gadget->dev.parent, "gadget not registered.\n");
359 mutex_unlock(&udc_lock);
364 dev_vdbg(gadget->dev.parent, "unregistering gadget\n");
366 list_del(&udc->list);
367 mutex_unlock(&udc_lock);
370 usb_gadget_remove_driver(udc);
372 kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE);
373 flush_work(&gadget->work);
374 device_unregister(&udc->dev);
375 device_unregister(&gadget->dev);
377 EXPORT_SYMBOL_GPL(usb_del_gadget_udc);
379 /* ------------------------------------------------------------------------- */
381 static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *driver)
385 dev_dbg(&udc->dev, "registering UDC driver [%s]\n",
388 udc->driver = driver;
389 udc->dev.driver = &driver->driver;
390 udc->gadget->dev.driver = &driver->driver;
392 ret = driver->bind(udc->gadget, driver);
395 ret = usb_gadget_udc_start(udc);
397 driver->unbind(udc->gadget);
400 usb_gadget_connect(udc->gadget);
402 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
406 dev_err(&udc->dev, "failed to start %s: %d\n",
407 udc->driver->function, ret);
409 udc->dev.driver = NULL;
410 udc->gadget->dev.driver = NULL;
414 int usb_udc_attach_driver(const char *name, struct usb_gadget_driver *driver)
416 struct usb_udc *udc = NULL;
419 mutex_lock(&udc_lock);
420 list_for_each_entry(udc, &udc_list, list) {
421 ret = strcmp(name, dev_name(&udc->dev));
433 ret = udc_bind_to_driver(udc, driver);
435 mutex_unlock(&udc_lock);
438 EXPORT_SYMBOL_GPL(usb_udc_attach_driver);
440 int usb_gadget_probe_driver(struct usb_gadget_driver *driver)
442 struct usb_udc *udc = NULL;
445 if (!driver || !driver->bind || !driver->setup)
448 mutex_lock(&udc_lock);
449 list_for_each_entry(udc, &udc_list, list) {
450 /* For now we take the first one */
455 pr_debug("couldn't find an available UDC\n");
456 mutex_unlock(&udc_lock);
459 ret = udc_bind_to_driver(udc, driver);
460 mutex_unlock(&udc_lock);
463 EXPORT_SYMBOL_GPL(usb_gadget_probe_driver);
465 int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
467 struct usb_udc *udc = NULL;
470 if (!driver || !driver->unbind)
473 mutex_lock(&udc_lock);
474 list_for_each_entry(udc, &udc_list, list)
475 if (udc->driver == driver) {
476 usb_gadget_remove_driver(udc);
477 usb_gadget_set_state(udc->gadget,
478 USB_STATE_NOTATTACHED);
483 mutex_unlock(&udc_lock);
486 EXPORT_SYMBOL_GPL(usb_gadget_unregister_driver);
488 /* ------------------------------------------------------------------------- */
490 static ssize_t usb_udc_srp_store(struct device *dev,
491 struct device_attribute *attr, const char *buf, size_t n)
493 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
495 if (sysfs_streq(buf, "1"))
496 usb_gadget_wakeup(udc->gadget);
500 static DEVICE_ATTR(srp, S_IWUSR, NULL, usb_udc_srp_store);
502 static ssize_t usb_udc_softconn_store(struct device *dev,
503 struct device_attribute *attr, const char *buf, size_t n)
505 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
508 dev_err(dev, "soft-connect without a gadget driver\n");
512 if (sysfs_streq(buf, "connect")) {
513 usb_gadget_udc_start(udc);
514 usb_gadget_connect(udc->gadget);
515 } else if (sysfs_streq(buf, "disconnect")) {
516 usb_gadget_disconnect(udc->gadget);
517 udc->driver->disconnect(udc->gadget);
518 usb_gadget_udc_stop(udc);
520 dev_err(dev, "unsupported command '%s'\n", buf);
526 static DEVICE_ATTR(soft_connect, S_IWUSR, NULL, usb_udc_softconn_store);
528 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
531 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
532 struct usb_gadget *gadget = udc->gadget;
534 return sprintf(buf, "%s\n", usb_state_string(gadget->state));
536 static DEVICE_ATTR_RO(state);
538 #define USB_UDC_SPEED_ATTR(name, param) \
539 ssize_t name##_show(struct device *dev, \
540 struct device_attribute *attr, char *buf) \
542 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
543 return snprintf(buf, PAGE_SIZE, "%s\n", \
544 usb_speed_string(udc->gadget->param)); \
546 static DEVICE_ATTR_RO(name)
548 static USB_UDC_SPEED_ATTR(current_speed, speed);
549 static USB_UDC_SPEED_ATTR(maximum_speed, max_speed);
551 #define USB_UDC_ATTR(name) \
552 ssize_t name##_show(struct device *dev, \
553 struct device_attribute *attr, char *buf) \
555 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
556 struct usb_gadget *gadget = udc->gadget; \
558 return snprintf(buf, PAGE_SIZE, "%d\n", gadget->name); \
560 static DEVICE_ATTR_RO(name)
562 static USB_UDC_ATTR(is_otg);
563 static USB_UDC_ATTR(is_a_peripheral);
564 static USB_UDC_ATTR(b_hnp_enable);
565 static USB_UDC_ATTR(a_hnp_support);
566 static USB_UDC_ATTR(a_alt_hnp_support);
568 static struct attribute *usb_udc_attrs[] = {
570 &dev_attr_soft_connect.attr,
571 &dev_attr_state.attr,
572 &dev_attr_current_speed.attr,
573 &dev_attr_maximum_speed.attr,
575 &dev_attr_is_otg.attr,
576 &dev_attr_is_a_peripheral.attr,
577 &dev_attr_b_hnp_enable.attr,
578 &dev_attr_a_hnp_support.attr,
579 &dev_attr_a_alt_hnp_support.attr,
583 static const struct attribute_group usb_udc_attr_group = {
584 .attrs = usb_udc_attrs,
587 static const struct attribute_group *usb_udc_attr_groups[] = {
592 static int usb_udc_uevent(struct device *dev, struct kobj_uevent_env *env)
594 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
597 ret = add_uevent_var(env, "USB_UDC_NAME=%s", udc->gadget->name);
599 dev_err(dev, "failed to add uevent USB_UDC_NAME\n");
604 ret = add_uevent_var(env, "USB_UDC_DRIVER=%s",
605 udc->driver->function);
607 dev_err(dev, "failed to add uevent USB_UDC_DRIVER\n");
615 static int __init usb_udc_init(void)
617 udc_class = class_create(THIS_MODULE, "udc");
618 if (IS_ERR(udc_class)) {
619 pr_err("failed to create udc class --> %ld\n",
621 return PTR_ERR(udc_class);
624 udc_class->dev_uevent = usb_udc_uevent;
627 subsys_initcall(usb_udc_init);
629 static void __exit usb_udc_exit(void)
631 class_destroy(udc_class);
633 module_exit(usb_udc_exit);
635 MODULE_DESCRIPTION("UDC Framework");
636 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
637 MODULE_LICENSE("GPL v2");