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 DEFINE_MUTEX(udc_lock);
56 /* ------------------------------------------------------------------------- */
60 int usb_gadget_map_request(struct usb_gadget *gadget,
61 struct usb_request *req, int is_in)
69 mapped = dma_map_sg(&gadget->dev, req->sg, req->num_sgs,
70 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
72 dev_err(&gadget->dev, "failed to map SGs\n");
76 req->num_mapped_sgs = mapped;
78 req->dma = dma_map_single(&gadget->dev, req->buf, req->length,
79 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
81 if (dma_mapping_error(&gadget->dev, req->dma)) {
82 dev_err(&gadget->dev, "failed to map buffer\n");
89 EXPORT_SYMBOL_GPL(usb_gadget_map_request);
91 void usb_gadget_unmap_request(struct usb_gadget *gadget,
92 struct usb_request *req, int is_in)
97 if (req->num_mapped_sgs) {
98 dma_unmap_sg(&gadget->dev, req->sg, req->num_mapped_sgs,
99 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
101 req->num_mapped_sgs = 0;
103 dma_unmap_single(&gadget->dev, req->dma, req->length,
104 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
107 EXPORT_SYMBOL_GPL(usb_gadget_unmap_request);
109 #endif /* CONFIG_HAS_DMA */
111 /* ------------------------------------------------------------------------- */
114 * usb_gadget_giveback_request - give the request back to the gadget layer
115 * Context: in_interrupt()
117 * This is called by device controller drivers in order to return the
118 * completed request back to the gadget layer.
120 void usb_gadget_giveback_request(struct usb_ep *ep,
121 struct usb_request *req)
123 if (likely(req->status == 0))
124 usb_led_activity(USB_LED_EVENT_GADGET);
126 req->complete(ep, req);
128 EXPORT_SYMBOL_GPL(usb_gadget_giveback_request);
130 /* ------------------------------------------------------------------------- */
132 static void usb_gadget_state_work(struct work_struct *work)
134 struct usb_gadget *gadget = work_to_gadget(work);
135 struct usb_udc *udc = gadget->udc;
138 sysfs_notify(&udc->dev.kobj, NULL, "state");
141 void usb_gadget_set_state(struct usb_gadget *gadget,
142 enum usb_device_state state)
144 gadget->state = state;
145 schedule_work(&gadget->work);
147 EXPORT_SYMBOL_GPL(usb_gadget_set_state);
149 /* ------------------------------------------------------------------------- */
151 static void usb_udc_connect_control(struct usb_udc *udc)
154 usb_gadget_connect(udc->gadget);
156 usb_gadget_disconnect(udc->gadget);
160 * usb_udc_vbus_handler - updates the udc core vbus status, and try to
161 * connect or disconnect gadget
162 * @gadget: The gadget which vbus change occurs
163 * @status: The vbus status
165 * The udc driver calls it when it wants to connect or disconnect gadget
166 * according to vbus status.
168 void usb_udc_vbus_handler(struct usb_gadget *gadget, bool status)
170 struct usb_udc *udc = gadget->udc;
174 usb_udc_connect_control(udc);
177 EXPORT_SYMBOL_GPL(usb_udc_vbus_handler);
180 * usb_gadget_udc_reset - notifies the udc core that bus reset occurs
181 * @gadget: The gadget which bus reset occurs
182 * @driver: The gadget driver we want to notify
184 * If the udc driver has bus reset handler, it needs to call this when the bus
185 * reset occurs, it notifies the gadget driver that the bus reset occurs as
186 * well as updates gadget state.
188 void usb_gadget_udc_reset(struct usb_gadget *gadget,
189 struct usb_gadget_driver *driver)
191 driver->reset(gadget);
192 usb_gadget_set_state(gadget, USB_STATE_DEFAULT);
194 EXPORT_SYMBOL_GPL(usb_gadget_udc_reset);
197 * usb_gadget_udc_start - tells usb device controller to start up
198 * @udc: The UDC to be started
200 * This call is issued by the UDC Class driver when it's about
201 * to register a gadget driver to the device controller, before
202 * calling gadget driver's bind() method.
204 * It allows the controller to be powered off until strictly
205 * necessary to have it powered on.
207 * Returns zero on success, else negative errno.
209 static inline int usb_gadget_udc_start(struct usb_udc *udc)
211 return udc->gadget->ops->udc_start(udc->gadget, udc->driver);
215 * usb_gadget_udc_stop - tells usb device controller we don't need it anymore
216 * @gadget: The device we want to stop activity
217 * @driver: The driver to unbind from @gadget
219 * This call is issued by the UDC Class driver after calling
220 * gadget driver's unbind() method.
222 * The details are implementation specific, but it can go as
223 * far as powering off UDC completely and disable its data
226 static inline void usb_gadget_udc_stop(struct usb_udc *udc)
228 udc->gadget->ops->udc_stop(udc->gadget);
232 * usb_udc_release - release the usb_udc struct
233 * @dev: the dev member within usb_udc
235 * This is called by driver's core in order to free memory once the last
236 * reference is released.
238 static void usb_udc_release(struct device *dev)
242 udc = container_of(dev, struct usb_udc, dev);
243 dev_dbg(dev, "releasing '%s'\n", dev_name(dev));
247 static const struct attribute_group *usb_udc_attr_groups[];
249 static void usb_udc_nop_release(struct device *dev)
251 dev_vdbg(dev, "%s\n", __func__);
255 * usb_add_gadget_udc_release - adds a new gadget to the udc class driver list
256 * @parent: the parent device to this udc. Usually the controller driver's
258 * @gadget: the gadget to be added to the list.
259 * @release: a gadget release function.
261 * Returns zero on success, negative errno otherwise.
263 int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
264 void (*release)(struct device *dev))
269 udc = kzalloc(sizeof(*udc), GFP_KERNEL);
273 dev_set_name(&gadget->dev, "gadget");
274 INIT_WORK(&gadget->work, usb_gadget_state_work);
275 gadget->dev.parent = parent;
277 #ifdef CONFIG_HAS_DMA
278 dma_set_coherent_mask(&gadget->dev, parent->coherent_dma_mask);
279 gadget->dev.dma_parms = parent->dma_parms;
280 gadget->dev.dma_mask = parent->dma_mask;
284 gadget->dev.release = release;
286 gadget->dev.release = usb_udc_nop_release;
288 ret = device_register(&gadget->dev);
292 device_initialize(&udc->dev);
293 udc->dev.release = usb_udc_release;
294 udc->dev.class = udc_class;
295 udc->dev.groups = usb_udc_attr_groups;
296 udc->dev.parent = parent;
297 ret = dev_set_name(&udc->dev, "%s", kobject_name(&parent->kobj));
301 udc->gadget = gadget;
304 mutex_lock(&udc_lock);
305 list_add_tail(&udc->list, &udc_list);
307 ret = device_add(&udc->dev);
311 usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED);
314 mutex_unlock(&udc_lock);
319 list_del(&udc->list);
320 mutex_unlock(&udc_lock);
323 put_device(&udc->dev);
324 device_del(&gadget->dev);
327 put_device(&gadget->dev);
333 EXPORT_SYMBOL_GPL(usb_add_gadget_udc_release);
336 * usb_add_gadget_udc - adds a new gadget to the udc class driver list
337 * @parent: the parent device to this udc. Usually the controller
339 * @gadget: the gadget to be added to the list
341 * Returns zero on success, negative errno otherwise.
343 int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget)
345 return usb_add_gadget_udc_release(parent, gadget, NULL);
347 EXPORT_SYMBOL_GPL(usb_add_gadget_udc);
349 static void usb_gadget_remove_driver(struct usb_udc *udc)
351 dev_dbg(&udc->dev, "unregistering UDC driver [%s]\n",
352 udc->driver->function);
354 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
356 usb_gadget_disconnect(udc->gadget);
357 udc->driver->disconnect(udc->gadget);
358 udc->driver->unbind(udc->gadget);
359 usb_gadget_udc_stop(udc);
362 udc->dev.driver = NULL;
363 udc->gadget->dev.driver = NULL;
367 * usb_del_gadget_udc - deletes @udc from udc_list
368 * @gadget: the gadget to be removed.
370 * This, will call usb_gadget_unregister_driver() if
371 * the @udc is still busy.
373 void usb_del_gadget_udc(struct usb_gadget *gadget)
375 struct usb_udc *udc = gadget->udc;
380 dev_vdbg(gadget->dev.parent, "unregistering gadget\n");
382 mutex_lock(&udc_lock);
383 list_del(&udc->list);
384 mutex_unlock(&udc_lock);
387 usb_gadget_remove_driver(udc);
389 kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE);
390 flush_work(&gadget->work);
391 device_unregister(&udc->dev);
392 device_unregister(&gadget->dev);
394 EXPORT_SYMBOL_GPL(usb_del_gadget_udc);
396 /* ------------------------------------------------------------------------- */
398 static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *driver)
402 dev_dbg(&udc->dev, "registering UDC driver [%s]\n",
405 udc->driver = driver;
406 udc->dev.driver = &driver->driver;
407 udc->gadget->dev.driver = &driver->driver;
409 ret = driver->bind(udc->gadget, driver);
412 ret = usb_gadget_udc_start(udc);
414 driver->unbind(udc->gadget);
417 usb_udc_connect_control(udc);
419 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
423 dev_err(&udc->dev, "failed to start %s: %d\n",
424 udc->driver->function, ret);
426 udc->dev.driver = NULL;
427 udc->gadget->dev.driver = NULL;
431 int usb_udc_attach_driver(const char *name, struct usb_gadget_driver *driver)
433 struct usb_udc *udc = NULL;
436 mutex_lock(&udc_lock);
437 list_for_each_entry(udc, &udc_list, list) {
438 ret = strcmp(name, dev_name(&udc->dev));
450 ret = udc_bind_to_driver(udc, driver);
452 mutex_unlock(&udc_lock);
455 EXPORT_SYMBOL_GPL(usb_udc_attach_driver);
457 int usb_gadget_probe_driver(struct usb_gadget_driver *driver)
459 struct usb_udc *udc = NULL;
462 if (!driver || !driver->bind || !driver->setup)
465 mutex_lock(&udc_lock);
466 list_for_each_entry(udc, &udc_list, list) {
467 /* For now we take the first one */
472 pr_debug("couldn't find an available UDC\n");
473 mutex_unlock(&udc_lock);
476 ret = udc_bind_to_driver(udc, driver);
477 mutex_unlock(&udc_lock);
480 EXPORT_SYMBOL_GPL(usb_gadget_probe_driver);
482 int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
484 struct usb_udc *udc = NULL;
487 if (!driver || !driver->unbind)
490 mutex_lock(&udc_lock);
491 list_for_each_entry(udc, &udc_list, list)
492 if (udc->driver == driver) {
493 usb_gadget_remove_driver(udc);
494 usb_gadget_set_state(udc->gadget,
495 USB_STATE_NOTATTACHED);
500 mutex_unlock(&udc_lock);
503 EXPORT_SYMBOL_GPL(usb_gadget_unregister_driver);
505 /* ------------------------------------------------------------------------- */
507 static ssize_t usb_udc_srp_store(struct device *dev,
508 struct device_attribute *attr, const char *buf, size_t n)
510 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
512 if (sysfs_streq(buf, "1"))
513 usb_gadget_wakeup(udc->gadget);
517 static DEVICE_ATTR(srp, S_IWUSR, NULL, usb_udc_srp_store);
519 static ssize_t usb_udc_softconn_store(struct device *dev,
520 struct device_attribute *attr, const char *buf, size_t n)
522 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
525 dev_err(dev, "soft-connect without a gadget driver\n");
529 if (sysfs_streq(buf, "connect")) {
530 usb_gadget_udc_start(udc);
531 usb_gadget_connect(udc->gadget);
532 } else if (sysfs_streq(buf, "disconnect")) {
533 usb_gadget_disconnect(udc->gadget);
534 udc->driver->disconnect(udc->gadget);
535 usb_gadget_udc_stop(udc);
537 dev_err(dev, "unsupported command '%s'\n", buf);
543 static DEVICE_ATTR(soft_connect, S_IWUSR, NULL, usb_udc_softconn_store);
545 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
548 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
549 struct usb_gadget *gadget = udc->gadget;
551 return sprintf(buf, "%s\n", usb_state_string(gadget->state));
553 static DEVICE_ATTR_RO(state);
555 #define USB_UDC_SPEED_ATTR(name, param) \
556 ssize_t name##_show(struct device *dev, \
557 struct device_attribute *attr, char *buf) \
559 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
560 return snprintf(buf, PAGE_SIZE, "%s\n", \
561 usb_speed_string(udc->gadget->param)); \
563 static DEVICE_ATTR_RO(name)
565 static USB_UDC_SPEED_ATTR(current_speed, speed);
566 static USB_UDC_SPEED_ATTR(maximum_speed, max_speed);
568 #define USB_UDC_ATTR(name) \
569 ssize_t name##_show(struct device *dev, \
570 struct device_attribute *attr, char *buf) \
572 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
573 struct usb_gadget *gadget = udc->gadget; \
575 return snprintf(buf, PAGE_SIZE, "%d\n", gadget->name); \
577 static DEVICE_ATTR_RO(name)
579 static USB_UDC_ATTR(is_otg);
580 static USB_UDC_ATTR(is_a_peripheral);
581 static USB_UDC_ATTR(b_hnp_enable);
582 static USB_UDC_ATTR(a_hnp_support);
583 static USB_UDC_ATTR(a_alt_hnp_support);
584 static USB_UDC_ATTR(is_selfpowered);
586 static struct attribute *usb_udc_attrs[] = {
588 &dev_attr_soft_connect.attr,
589 &dev_attr_state.attr,
590 &dev_attr_current_speed.attr,
591 &dev_attr_maximum_speed.attr,
593 &dev_attr_is_otg.attr,
594 &dev_attr_is_a_peripheral.attr,
595 &dev_attr_b_hnp_enable.attr,
596 &dev_attr_a_hnp_support.attr,
597 &dev_attr_a_alt_hnp_support.attr,
598 &dev_attr_is_selfpowered.attr,
602 static const struct attribute_group usb_udc_attr_group = {
603 .attrs = usb_udc_attrs,
606 static const struct attribute_group *usb_udc_attr_groups[] = {
611 static int usb_udc_uevent(struct device *dev, struct kobj_uevent_env *env)
613 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
616 ret = add_uevent_var(env, "USB_UDC_NAME=%s", udc->gadget->name);
618 dev_err(dev, "failed to add uevent USB_UDC_NAME\n");
623 ret = add_uevent_var(env, "USB_UDC_DRIVER=%s",
624 udc->driver->function);
626 dev_err(dev, "failed to add uevent USB_UDC_DRIVER\n");
634 static int __init usb_udc_init(void)
636 udc_class = class_create(THIS_MODULE, "udc");
637 if (IS_ERR(udc_class)) {
638 pr_err("failed to create udc class --> %ld\n",
640 return PTR_ERR(udc_class);
643 udc_class->dev_uevent = usb_udc_uevent;
646 subsys_initcall(usb_udc_init);
648 static void __exit usb_udc_exit(void)
650 class_destroy(udc_class);
652 module_exit(usb_udc_exit);
654 MODULE_DESCRIPTION("UDC Framework");
655 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
656 MODULE_LICENSE("GPL v2");