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 * @gadget: The gadget we want to get started
178 * @driver: The driver we want to bind to @gadget
180 * This call is issued by the UDC Class driver when it's about
181 * to register a gadget driver to the device controller, before
182 * calling gadget driver's bind() method.
184 * It allows the controller to be powered off until strictly
185 * necessary to have it powered on.
187 * Returns zero on success, else negative errno.
189 static inline int usb_gadget_udc_start(struct usb_gadget *gadget,
190 struct usb_gadget_driver *driver)
192 return gadget->ops->udc_start(gadget, driver);
196 * usb_gadget_udc_stop - tells usb device controller we don't need it anymore
197 * @gadget: The device we want to stop activity
198 * @driver: The driver to unbind from @gadget
200 * This call is issued by the UDC Class driver after calling
201 * gadget driver's unbind() method.
203 * The details are implementation specific, but it can go as
204 * far as powering off UDC completely and disable its data
207 static inline void usb_gadget_udc_stop(struct usb_gadget *gadget,
208 struct usb_gadget_driver *driver)
210 gadget->ops->udc_stop(gadget, driver);
214 * usb_udc_release - release the usb_udc struct
215 * @dev: the dev member within usb_udc
217 * This is called by driver's core in order to free memory once the last
218 * reference is released.
220 static void usb_udc_release(struct device *dev)
224 udc = container_of(dev, struct usb_udc, dev);
225 dev_dbg(dev, "releasing '%s'\n", dev_name(dev));
229 static const struct attribute_group *usb_udc_attr_groups[];
231 static void usb_udc_nop_release(struct device *dev)
233 dev_vdbg(dev, "%s\n", __func__);
237 * usb_add_gadget_udc_release - adds a new gadget to the udc class driver list
238 * @parent: the parent device to this udc. Usually the controller driver's
240 * @gadget: the gadget to be added to the list.
241 * @release: a gadget release function.
243 * Returns zero on success, negative errno otherwise.
245 int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
246 void (*release)(struct device *dev))
251 udc = kzalloc(sizeof(*udc), GFP_KERNEL);
255 dev_set_name(&gadget->dev, "gadget");
256 INIT_WORK(&gadget->work, usb_gadget_state_work);
257 gadget->dev.parent = parent;
259 #ifdef CONFIG_HAS_DMA
260 dma_set_coherent_mask(&gadget->dev, parent->coherent_dma_mask);
261 gadget->dev.dma_parms = parent->dma_parms;
262 gadget->dev.dma_mask = parent->dma_mask;
266 gadget->dev.release = release;
268 gadget->dev.release = usb_udc_nop_release;
270 ret = device_register(&gadget->dev);
274 device_initialize(&udc->dev);
275 udc->dev.release = usb_udc_release;
276 udc->dev.class = udc_class;
277 udc->dev.groups = usb_udc_attr_groups;
278 udc->dev.parent = parent;
279 ret = dev_set_name(&udc->dev, "%s", kobject_name(&parent->kobj));
283 udc->gadget = gadget;
285 mutex_lock(&udc_lock);
286 list_add_tail(&udc->list, &udc_list);
288 ret = device_add(&udc->dev);
292 usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED);
294 mutex_unlock(&udc_lock);
299 list_del(&udc->list);
300 mutex_unlock(&udc_lock);
303 put_device(&udc->dev);
306 put_device(&gadget->dev);
312 EXPORT_SYMBOL_GPL(usb_add_gadget_udc_release);
315 * usb_add_gadget_udc - adds a new gadget to the udc class driver list
316 * @parent: the parent device to this udc. Usually the controller
318 * @gadget: the gadget to be added to the list
320 * Returns zero on success, negative errno otherwise.
322 int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget)
324 return usb_add_gadget_udc_release(parent, gadget, NULL);
326 EXPORT_SYMBOL_GPL(usb_add_gadget_udc);
328 static void usb_gadget_remove_driver(struct usb_udc *udc)
330 dev_dbg(&udc->dev, "unregistering UDC driver [%s]\n",
333 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
335 usb_gadget_disconnect(udc->gadget);
336 udc->driver->disconnect(udc->gadget);
337 udc->driver->unbind(udc->gadget);
338 usb_gadget_udc_stop(udc->gadget, NULL);
341 udc->dev.driver = NULL;
342 udc->gadget->dev.driver = NULL;
346 * usb_del_gadget_udc - deletes @udc from udc_list
347 * @gadget: the gadget to be removed.
349 * This, will call usb_gadget_unregister_driver() if
350 * the @udc is still busy.
352 void usb_del_gadget_udc(struct usb_gadget *gadget)
354 struct usb_udc *udc = NULL;
356 mutex_lock(&udc_lock);
357 list_for_each_entry(udc, &udc_list, list)
358 if (udc->gadget == gadget)
361 dev_err(gadget->dev.parent, "gadget not registered.\n");
362 mutex_unlock(&udc_lock);
367 dev_vdbg(gadget->dev.parent, "unregistering gadget\n");
369 list_del(&udc->list);
370 mutex_unlock(&udc_lock);
373 usb_gadget_remove_driver(udc);
375 kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE);
376 flush_work(&gadget->work);
377 device_unregister(&udc->dev);
378 device_unregister(&gadget->dev);
380 EXPORT_SYMBOL_GPL(usb_del_gadget_udc);
382 /* ------------------------------------------------------------------------- */
384 static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *driver)
388 dev_dbg(&udc->dev, "registering UDC driver [%s]\n",
391 udc->driver = driver;
392 udc->dev.driver = &driver->driver;
393 udc->gadget->dev.driver = &driver->driver;
395 ret = driver->bind(udc->gadget, driver);
398 ret = usb_gadget_udc_start(udc->gadget, driver);
400 driver->unbind(udc->gadget);
403 usb_gadget_connect(udc->gadget);
405 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
409 dev_err(&udc->dev, "failed to start %s: %d\n",
410 udc->driver->function, ret);
412 udc->dev.driver = NULL;
413 udc->gadget->dev.driver = NULL;
417 int udc_attach_driver(const char *name, struct usb_gadget_driver *driver)
419 struct usb_udc *udc = NULL;
422 mutex_lock(&udc_lock);
423 list_for_each_entry(udc, &udc_list, list) {
424 ret = strcmp(name, dev_name(&udc->dev));
436 ret = udc_bind_to_driver(udc, driver);
438 mutex_unlock(&udc_lock);
441 EXPORT_SYMBOL_GPL(udc_attach_driver);
443 int usb_gadget_probe_driver(struct usb_gadget_driver *driver)
445 struct usb_udc *udc = NULL;
448 if (!driver || !driver->bind || !driver->setup)
451 mutex_lock(&udc_lock);
452 list_for_each_entry(udc, &udc_list, list) {
453 /* For now we take the first one */
458 pr_debug("couldn't find an available UDC\n");
459 mutex_unlock(&udc_lock);
462 ret = udc_bind_to_driver(udc, driver);
463 mutex_unlock(&udc_lock);
466 EXPORT_SYMBOL_GPL(usb_gadget_probe_driver);
468 int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
470 struct usb_udc *udc = NULL;
473 if (!driver || !driver->unbind)
476 mutex_lock(&udc_lock);
477 list_for_each_entry(udc, &udc_list, list)
478 if (udc->driver == driver) {
479 usb_gadget_remove_driver(udc);
480 usb_gadget_set_state(udc->gadget,
481 USB_STATE_NOTATTACHED);
486 mutex_unlock(&udc_lock);
489 EXPORT_SYMBOL_GPL(usb_gadget_unregister_driver);
491 /* ------------------------------------------------------------------------- */
493 static ssize_t usb_udc_srp_store(struct device *dev,
494 struct device_attribute *attr, const char *buf, size_t n)
496 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
498 if (sysfs_streq(buf, "1"))
499 usb_gadget_wakeup(udc->gadget);
503 static DEVICE_ATTR(srp, S_IWUSR, NULL, usb_udc_srp_store);
505 static ssize_t usb_udc_softconn_store(struct device *dev,
506 struct device_attribute *attr, const char *buf, size_t n)
508 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
510 if (sysfs_streq(buf, "connect")) {
511 usb_gadget_udc_start(udc->gadget, udc->driver);
512 usb_gadget_connect(udc->gadget);
513 } else if (sysfs_streq(buf, "disconnect")) {
514 usb_gadget_disconnect(udc->gadget);
515 usb_gadget_udc_stop(udc->gadget, udc->driver);
517 dev_err(dev, "unsupported command '%s'\n", buf);
523 static DEVICE_ATTR(soft_connect, S_IWUSR, NULL, usb_udc_softconn_store);
525 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
528 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
529 struct usb_gadget *gadget = udc->gadget;
531 return sprintf(buf, "%s\n", usb_state_string(gadget->state));
533 static DEVICE_ATTR_RO(state);
535 #define USB_UDC_SPEED_ATTR(name, param) \
536 ssize_t name##_show(struct device *dev, \
537 struct device_attribute *attr, char *buf) \
539 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
540 return snprintf(buf, PAGE_SIZE, "%s\n", \
541 usb_speed_string(udc->gadget->param)); \
543 static DEVICE_ATTR_RO(name)
545 static USB_UDC_SPEED_ATTR(current_speed, speed);
546 static USB_UDC_SPEED_ATTR(maximum_speed, max_speed);
548 #define USB_UDC_ATTR(name) \
549 ssize_t name##_show(struct device *dev, \
550 struct device_attribute *attr, char *buf) \
552 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
553 struct usb_gadget *gadget = udc->gadget; \
555 return snprintf(buf, PAGE_SIZE, "%d\n", gadget->name); \
557 static DEVICE_ATTR_RO(name)
559 static USB_UDC_ATTR(is_otg);
560 static USB_UDC_ATTR(is_a_peripheral);
561 static USB_UDC_ATTR(b_hnp_enable);
562 static USB_UDC_ATTR(a_hnp_support);
563 static USB_UDC_ATTR(a_alt_hnp_support);
565 static struct attribute *usb_udc_attrs[] = {
567 &dev_attr_soft_connect.attr,
568 &dev_attr_state.attr,
569 &dev_attr_current_speed.attr,
570 &dev_attr_maximum_speed.attr,
572 &dev_attr_is_otg.attr,
573 &dev_attr_is_a_peripheral.attr,
574 &dev_attr_b_hnp_enable.attr,
575 &dev_attr_a_hnp_support.attr,
576 &dev_attr_a_alt_hnp_support.attr,
580 static const struct attribute_group usb_udc_attr_group = {
581 .attrs = usb_udc_attrs,
584 static const struct attribute_group *usb_udc_attr_groups[] = {
589 static int usb_udc_uevent(struct device *dev, struct kobj_uevent_env *env)
591 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
594 ret = add_uevent_var(env, "USB_UDC_NAME=%s", udc->gadget->name);
596 dev_err(dev, "failed to add uevent USB_UDC_NAME\n");
601 ret = add_uevent_var(env, "USB_UDC_DRIVER=%s",
602 udc->driver->function);
604 dev_err(dev, "failed to add uevent USB_UDC_DRIVER\n");
612 static int __init usb_udc_init(void)
614 udc_class = class_create(THIS_MODULE, "udc");
615 if (IS_ERR(udc_class)) {
616 pr_err("failed to create udc class --> %ld\n",
618 return PTR_ERR(udc_class);
621 udc_class->dev_uevent = usb_udc_uevent;
624 subsys_initcall(usb_udc_init);
626 static void __exit usb_udc_exit(void)
628 class_destroy(udc_class);
630 module_exit(usb_udc_exit);
632 MODULE_DESCRIPTION("UDC Framework");
633 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
634 MODULE_LICENSE("GPL v2");