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>
32 * struct usb_udc - describes one usb device controller
33 * @driver - the gadget driver pointer. For use by the class code
34 * @dev - the child device to the actual controller
35 * @gadget - the gadget. For use by the class code
36 * @list - for use by the udc class driver
38 * This represents the internal data structure which is used by the UDC-class
39 * to hold information about udc driver and gadget together.
42 struct usb_gadget_driver *driver;
43 struct usb_gadget *gadget;
45 struct list_head list;
48 static struct class *udc_class;
49 static LIST_HEAD(udc_list);
50 static DEFINE_MUTEX(udc_lock);
52 /* ------------------------------------------------------------------------- */
56 int usb_gadget_map_request(struct usb_gadget *gadget,
57 struct usb_request *req, int is_in)
65 mapped = dma_map_sg(&gadget->dev, req->sg, req->num_sgs,
66 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
68 dev_err(&gadget->dev, "failed to map SGs\n");
72 req->num_mapped_sgs = mapped;
74 req->dma = dma_map_single(&gadget->dev, req->buf, req->length,
75 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
77 if (dma_mapping_error(&gadget->dev, req->dma)) {
78 dev_err(&gadget->dev, "failed to map buffer\n");
85 EXPORT_SYMBOL_GPL(usb_gadget_map_request);
87 void usb_gadget_unmap_request(struct usb_gadget *gadget,
88 struct usb_request *req, int is_in)
93 if (req->num_mapped_sgs) {
94 dma_unmap_sg(&gadget->dev, req->sg, req->num_mapped_sgs,
95 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
97 req->num_mapped_sgs = 0;
99 dma_unmap_single(&gadget->dev, req->dma, req->length,
100 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
103 EXPORT_SYMBOL_GPL(usb_gadget_unmap_request);
105 #endif /* CONFIG_HAS_DMA */
107 /* ------------------------------------------------------------------------- */
109 static void usb_gadget_state_work(struct work_struct *work)
111 struct usb_gadget *gadget = work_to_gadget(work);
113 sysfs_notify(&gadget->dev.kobj, NULL, "state");
116 void usb_gadget_set_state(struct usb_gadget *gadget,
117 enum usb_device_state state)
119 gadget->state = state;
120 schedule_work(&gadget->work);
122 EXPORT_SYMBOL_GPL(usb_gadget_set_state);
124 /* ------------------------------------------------------------------------- */
127 * usb_gadget_udc_reset - notifies the udc core that bus reset occurs
128 * @gadget: The gadget which bus reset occurs
129 * @driver: The gadget driver we want to notify
131 * If the udc driver has bus reset handler, it needs to call this when the bus
132 * reset occurs, it notifies the gadget driver that the bus reset occurs as
133 * well as updates gadget state.
135 void usb_gadget_udc_reset(struct usb_gadget *gadget,
136 struct usb_gadget_driver *driver)
138 driver->reset(gadget);
139 usb_gadget_set_state(gadget, USB_STATE_DEFAULT);
141 EXPORT_SYMBOL_GPL(usb_gadget_udc_reset);
144 * usb_gadget_udc_start - tells usb device controller to start up
145 * @gadget: The gadget we want to get started
146 * @driver: The driver we want to bind to @gadget
148 * This call is issued by the UDC Class driver when it's about
149 * to register a gadget driver to the device controller, before
150 * calling gadget driver's bind() method.
152 * It allows the controller to be powered off until strictly
153 * necessary to have it powered on.
155 * Returns zero on success, else negative errno.
157 static inline int usb_gadget_udc_start(struct usb_gadget *gadget,
158 struct usb_gadget_driver *driver)
160 return gadget->ops->udc_start(gadget, driver);
164 * usb_gadget_udc_stop - tells usb device controller we don't need it anymore
165 * @gadget: The device we want to stop activity
166 * @driver: The driver to unbind from @gadget
168 * This call is issued by the UDC Class driver after calling
169 * gadget driver's unbind() method.
171 * The details are implementation specific, but it can go as
172 * far as powering off UDC completely and disable its data
175 static inline void usb_gadget_udc_stop(struct usb_gadget *gadget,
176 struct usb_gadget_driver *driver)
178 gadget->ops->udc_stop(gadget, driver);
182 * usb_udc_release - release the usb_udc struct
183 * @dev: the dev member within usb_udc
185 * This is called by driver's core in order to free memory once the last
186 * reference is released.
188 static void usb_udc_release(struct device *dev)
192 udc = container_of(dev, struct usb_udc, dev);
193 dev_dbg(dev, "releasing '%s'\n", dev_name(dev));
197 static const struct attribute_group *usb_udc_attr_groups[];
199 static void usb_udc_nop_release(struct device *dev)
201 dev_vdbg(dev, "%s\n", __func__);
205 * usb_add_gadget_udc_release - adds a new gadget to the udc class driver list
206 * @parent: the parent device to this udc. Usually the controller driver's
208 * @gadget: the gadget to be added to the list.
209 * @release: a gadget release function.
211 * Returns zero on success, negative errno otherwise.
213 int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
214 void (*release)(struct device *dev))
219 udc = kzalloc(sizeof(*udc), GFP_KERNEL);
223 dev_set_name(&gadget->dev, "gadget");
224 INIT_WORK(&gadget->work, usb_gadget_state_work);
225 gadget->dev.parent = parent;
227 #ifdef CONFIG_HAS_DMA
228 dma_set_coherent_mask(&gadget->dev, parent->coherent_dma_mask);
229 gadget->dev.dma_parms = parent->dma_parms;
230 gadget->dev.dma_mask = parent->dma_mask;
234 gadget->dev.release = release;
236 gadget->dev.release = usb_udc_nop_release;
238 ret = device_register(&gadget->dev);
242 device_initialize(&udc->dev);
243 udc->dev.release = usb_udc_release;
244 udc->dev.class = udc_class;
245 udc->dev.groups = usb_udc_attr_groups;
246 udc->dev.parent = parent;
247 ret = dev_set_name(&udc->dev, "%s", kobject_name(&parent->kobj));
251 udc->gadget = gadget;
253 mutex_lock(&udc_lock);
254 list_add_tail(&udc->list, &udc_list);
256 ret = device_add(&udc->dev);
260 usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED);
262 mutex_unlock(&udc_lock);
267 list_del(&udc->list);
268 mutex_unlock(&udc_lock);
271 put_device(&udc->dev);
274 put_device(&gadget->dev);
280 EXPORT_SYMBOL_GPL(usb_add_gadget_udc_release);
283 * usb_add_gadget_udc - adds a new gadget to the udc class driver list
284 * @parent: the parent device to this udc. Usually the controller
286 * @gadget: the gadget to be added to the list
288 * Returns zero on success, negative errno otherwise.
290 int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget)
292 return usb_add_gadget_udc_release(parent, gadget, NULL);
294 EXPORT_SYMBOL_GPL(usb_add_gadget_udc);
296 static void usb_gadget_remove_driver(struct usb_udc *udc)
298 dev_dbg(&udc->dev, "unregistering UDC driver [%s]\n",
301 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
303 usb_gadget_disconnect(udc->gadget);
304 udc->driver->disconnect(udc->gadget);
305 udc->driver->unbind(udc->gadget);
306 usb_gadget_udc_stop(udc->gadget, NULL);
309 udc->dev.driver = NULL;
310 udc->gadget->dev.driver = NULL;
314 * usb_del_gadget_udc - deletes @udc from udc_list
315 * @gadget: the gadget to be removed.
317 * This, will call usb_gadget_unregister_driver() if
318 * the @udc is still busy.
320 void usb_del_gadget_udc(struct usb_gadget *gadget)
322 struct usb_udc *udc = NULL;
324 mutex_lock(&udc_lock);
325 list_for_each_entry(udc, &udc_list, list)
326 if (udc->gadget == gadget)
329 dev_err(gadget->dev.parent, "gadget not registered.\n");
330 mutex_unlock(&udc_lock);
335 dev_vdbg(gadget->dev.parent, "unregistering gadget\n");
337 list_del(&udc->list);
338 mutex_unlock(&udc_lock);
341 usb_gadget_remove_driver(udc);
343 kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE);
344 flush_work(&gadget->work);
345 device_unregister(&udc->dev);
346 device_unregister(&gadget->dev);
348 EXPORT_SYMBOL_GPL(usb_del_gadget_udc);
350 /* ------------------------------------------------------------------------- */
352 static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *driver)
356 dev_dbg(&udc->dev, "registering UDC driver [%s]\n",
359 udc->driver = driver;
360 udc->dev.driver = &driver->driver;
361 udc->gadget->dev.driver = &driver->driver;
363 ret = driver->bind(udc->gadget, driver);
366 ret = usb_gadget_udc_start(udc->gadget, driver);
368 driver->unbind(udc->gadget);
371 usb_gadget_connect(udc->gadget);
373 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
377 dev_err(&udc->dev, "failed to start %s: %d\n",
378 udc->driver->function, ret);
380 udc->dev.driver = NULL;
381 udc->gadget->dev.driver = NULL;
385 int udc_attach_driver(const char *name, struct usb_gadget_driver *driver)
387 struct usb_udc *udc = NULL;
390 mutex_lock(&udc_lock);
391 list_for_each_entry(udc, &udc_list, list) {
392 ret = strcmp(name, dev_name(&udc->dev));
404 ret = udc_bind_to_driver(udc, driver);
406 mutex_unlock(&udc_lock);
409 EXPORT_SYMBOL_GPL(udc_attach_driver);
411 int usb_gadget_probe_driver(struct usb_gadget_driver *driver)
413 struct usb_udc *udc = NULL;
416 if (!driver || !driver->bind || !driver->setup)
419 mutex_lock(&udc_lock);
420 list_for_each_entry(udc, &udc_list, list) {
421 /* For now we take the first one */
426 pr_debug("couldn't find an available UDC\n");
427 mutex_unlock(&udc_lock);
430 ret = udc_bind_to_driver(udc, driver);
431 mutex_unlock(&udc_lock);
434 EXPORT_SYMBOL_GPL(usb_gadget_probe_driver);
436 int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
438 struct usb_udc *udc = NULL;
441 if (!driver || !driver->unbind)
444 mutex_lock(&udc_lock);
445 list_for_each_entry(udc, &udc_list, list)
446 if (udc->driver == driver) {
447 usb_gadget_remove_driver(udc);
448 usb_gadget_set_state(udc->gadget,
449 USB_STATE_NOTATTACHED);
454 mutex_unlock(&udc_lock);
457 EXPORT_SYMBOL_GPL(usb_gadget_unregister_driver);
459 /* ------------------------------------------------------------------------- */
461 static ssize_t usb_udc_srp_store(struct device *dev,
462 struct device_attribute *attr, const char *buf, size_t n)
464 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
466 if (sysfs_streq(buf, "1"))
467 usb_gadget_wakeup(udc->gadget);
471 static DEVICE_ATTR(srp, S_IWUSR, NULL, usb_udc_srp_store);
473 static ssize_t usb_udc_softconn_store(struct device *dev,
474 struct device_attribute *attr, const char *buf, size_t n)
476 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
478 if (sysfs_streq(buf, "connect")) {
479 usb_gadget_udc_start(udc->gadget, udc->driver);
480 usb_gadget_connect(udc->gadget);
481 } else if (sysfs_streq(buf, "disconnect")) {
482 usb_gadget_disconnect(udc->gadget);
483 usb_gadget_udc_stop(udc->gadget, udc->driver);
485 dev_err(dev, "unsupported command '%s'\n", buf);
491 static DEVICE_ATTR(soft_connect, S_IWUSR, NULL, usb_udc_softconn_store);
493 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
496 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
497 struct usb_gadget *gadget = udc->gadget;
499 return sprintf(buf, "%s\n", usb_state_string(gadget->state));
501 static DEVICE_ATTR_RO(state);
503 #define USB_UDC_SPEED_ATTR(name, param) \
504 ssize_t name##_show(struct device *dev, \
505 struct device_attribute *attr, char *buf) \
507 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
508 return snprintf(buf, PAGE_SIZE, "%s\n", \
509 usb_speed_string(udc->gadget->param)); \
511 static DEVICE_ATTR_RO(name)
513 static USB_UDC_SPEED_ATTR(current_speed, speed);
514 static USB_UDC_SPEED_ATTR(maximum_speed, max_speed);
516 #define USB_UDC_ATTR(name) \
517 ssize_t name##_show(struct device *dev, \
518 struct device_attribute *attr, char *buf) \
520 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
521 struct usb_gadget *gadget = udc->gadget; \
523 return snprintf(buf, PAGE_SIZE, "%d\n", gadget->name); \
525 static DEVICE_ATTR_RO(name)
527 static USB_UDC_ATTR(is_otg);
528 static USB_UDC_ATTR(is_a_peripheral);
529 static USB_UDC_ATTR(b_hnp_enable);
530 static USB_UDC_ATTR(a_hnp_support);
531 static USB_UDC_ATTR(a_alt_hnp_support);
533 static struct attribute *usb_udc_attrs[] = {
535 &dev_attr_soft_connect.attr,
536 &dev_attr_state.attr,
537 &dev_attr_current_speed.attr,
538 &dev_attr_maximum_speed.attr,
540 &dev_attr_is_otg.attr,
541 &dev_attr_is_a_peripheral.attr,
542 &dev_attr_b_hnp_enable.attr,
543 &dev_attr_a_hnp_support.attr,
544 &dev_attr_a_alt_hnp_support.attr,
548 static const struct attribute_group usb_udc_attr_group = {
549 .attrs = usb_udc_attrs,
552 static const struct attribute_group *usb_udc_attr_groups[] = {
557 static int usb_udc_uevent(struct device *dev, struct kobj_uevent_env *env)
559 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
562 ret = add_uevent_var(env, "USB_UDC_NAME=%s", udc->gadget->name);
564 dev_err(dev, "failed to add uevent USB_UDC_NAME\n");
569 ret = add_uevent_var(env, "USB_UDC_DRIVER=%s",
570 udc->driver->function);
572 dev_err(dev, "failed to add uevent USB_UDC_DRIVER\n");
580 static int __init usb_udc_init(void)
582 udc_class = class_create(THIS_MODULE, "udc");
583 if (IS_ERR(udc_class)) {
584 pr_err("failed to create udc class --> %ld\n",
586 return PTR_ERR(udc_class);
589 udc_class->dev_uevent = usb_udc_uevent;
592 subsys_initcall(usb_udc_init);
594 static void __exit usb_udc_exit(void)
596 class_destroy(udc_class);
598 module_exit(usb_udc_exit);
600 MODULE_DESCRIPTION("UDC Framework");
601 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
602 MODULE_LICENSE("GPL v2");