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>
27 #include <linux/usb/ch9.h>
28 #include <linux/usb/gadget.h>
31 * struct usb_udc - describes one usb device controller
32 * @driver - the gadget driver pointer. For use by the class code
33 * @dev - the child device to the actual controller
34 * @gadget - the gadget. For use by the class code
35 * @list - for use by the udc class driver
37 * This represents the internal data structure which is used by the UDC-class
38 * to hold information about udc driver and gadget together.
41 struct usb_gadget_driver *driver;
42 struct usb_gadget *gadget;
44 struct list_head list;
47 static struct class *udc_class;
48 static LIST_HEAD(udc_list);
49 static DEFINE_MUTEX(udc_lock);
51 /* ------------------------------------------------------------------------- */
53 int usb_gadget_map_request(struct usb_gadget *gadget,
54 struct usb_request *req, int is_in)
62 mapped = dma_map_sg(&gadget->dev, req->sg, req->num_sgs,
63 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
65 dev_err(&gadget->dev, "failed to map SGs\n");
69 req->num_mapped_sgs = mapped;
71 req->dma = dma_map_single(&gadget->dev, req->buf, req->length,
72 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
74 if (dma_mapping_error(&gadget->dev, req->dma)) {
75 dev_err(&gadget->dev, "failed to map buffer\n");
82 EXPORT_SYMBOL_GPL(usb_gadget_map_request);
84 void usb_gadget_unmap_request(struct usb_gadget *gadget,
85 struct usb_request *req, int is_in)
90 if (req->num_mapped_sgs) {
91 dma_unmap_sg(&gadget->dev, req->sg, req->num_mapped_sgs,
92 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
94 req->num_mapped_sgs = 0;
96 dma_unmap_single(&gadget->dev, req->dma, req->length,
97 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
100 EXPORT_SYMBOL_GPL(usb_gadget_unmap_request);
102 /* ------------------------------------------------------------------------- */
105 * usb_gadget_udc_start - tells usb device controller to start up
106 * @gadget: The gadget we want to get started
107 * @driver: The driver we want to bind to @gadget
109 * This call is issued by the UDC Class driver when it's about
110 * to register a gadget driver to the device controller, before
111 * calling gadget driver's bind() method.
113 * It allows the controller to be powered off until strictly
114 * necessary to have it powered on.
116 * Returns zero on success, else negative errno.
118 static inline int usb_gadget_udc_start(struct usb_gadget *gadget,
119 struct usb_gadget_driver *driver)
121 return gadget->ops->udc_start(gadget, driver);
125 * usb_gadget_udc_stop - tells usb device controller we don't need it anymore
126 * @gadget: The device we want to stop activity
127 * @driver: The driver to unbind from @gadget
129 * This call is issued by the UDC Class driver after calling
130 * gadget driver's unbind() method.
132 * The details are implementation specific, but it can go as
133 * far as powering off UDC completely and disable its data
136 static inline void usb_gadget_udc_stop(struct usb_gadget *gadget,
137 struct usb_gadget_driver *driver)
139 gadget->ops->udc_stop(gadget, driver);
143 * usb_udc_release - release the usb_udc struct
144 * @dev: the dev member within usb_udc
146 * This is called by driver's core in order to free memory once the last
147 * reference is released.
149 static void usb_udc_release(struct device *dev)
153 udc = container_of(dev, struct usb_udc, dev);
154 dev_dbg(dev, "releasing '%s'\n", dev_name(dev));
158 static const struct attribute_group *usb_udc_attr_groups[];
160 * usb_add_gadget_udc - adds a new gadget to the udc class driver list
161 * @parent: the parent device to this udc. Usually the controller
163 * @gadget: the gadget to be added to the list
165 * Returns zero on success, negative errno otherwise.
167 int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget)
172 udc = kzalloc(sizeof(*udc), GFP_KERNEL);
176 device_initialize(&udc->dev);
177 udc->dev.release = usb_udc_release;
178 udc->dev.class = udc_class;
179 udc->dev.groups = usb_udc_attr_groups;
180 udc->dev.parent = parent;
181 ret = dev_set_name(&udc->dev, "%s", kobject_name(&parent->kobj));
185 udc->gadget = gadget;
187 mutex_lock(&udc_lock);
188 list_add_tail(&udc->list, &udc_list);
190 ret = device_add(&udc->dev);
194 mutex_unlock(&udc_lock);
198 list_del(&udc->list);
199 mutex_unlock(&udc_lock);
202 put_device(&udc->dev);
207 EXPORT_SYMBOL_GPL(usb_add_gadget_udc);
209 static void usb_gadget_remove_driver(struct usb_udc *udc)
211 dev_dbg(&udc->dev, "unregistering UDC driver [%s]\n",
214 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
216 usb_gadget_disconnect(udc->gadget);
217 udc->driver->disconnect(udc->gadget);
218 udc->driver->unbind(udc->gadget);
219 usb_gadget_udc_stop(udc->gadget, udc->driver);
222 udc->dev.driver = NULL;
226 * usb_del_gadget_udc - deletes @udc from udc_list
227 * @gadget: the gadget to be removed.
229 * This, will call usb_gadget_unregister_driver() if
230 * the @udc is still busy.
232 void usb_del_gadget_udc(struct usb_gadget *gadget)
234 struct usb_udc *udc = NULL;
236 mutex_lock(&udc_lock);
237 list_for_each_entry(udc, &udc_list, list)
238 if (udc->gadget == gadget)
241 dev_err(gadget->dev.parent, "gadget not registered.\n");
242 mutex_unlock(&udc_lock);
247 dev_vdbg(gadget->dev.parent, "unregistering gadget\n");
249 list_del(&udc->list);
250 mutex_unlock(&udc_lock);
253 usb_gadget_remove_driver(udc);
255 kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE);
256 device_unregister(&udc->dev);
258 EXPORT_SYMBOL_GPL(usb_del_gadget_udc);
260 /* ------------------------------------------------------------------------- */
262 static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *driver)
266 dev_dbg(&udc->dev, "registering UDC driver [%s]\n",
269 udc->driver = driver;
270 udc->dev.driver = &driver->driver;
272 ret = driver->bind(udc->gadget, driver);
275 ret = usb_gadget_udc_start(udc->gadget, driver);
277 driver->unbind(udc->gadget);
280 usb_gadget_connect(udc->gadget);
282 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
285 dev_err(&udc->dev, "failed to start %s: %d\n",
286 udc->driver->function, ret);
288 udc->dev.driver = NULL;
292 int udc_attach_driver(const char *name, struct usb_gadget_driver *driver)
294 struct usb_udc *udc = NULL;
297 mutex_lock(&udc_lock);
298 list_for_each_entry(udc, &udc_list, list) {
299 ret = strcmp(name, dev_name(&udc->dev));
311 ret = udc_bind_to_driver(udc, driver);
313 mutex_unlock(&udc_lock);
316 EXPORT_SYMBOL_GPL(udc_attach_driver);
318 int usb_gadget_probe_driver(struct usb_gadget_driver *driver)
320 struct usb_udc *udc = NULL;
323 if (!driver || !driver->bind || !driver->setup)
326 mutex_lock(&udc_lock);
327 list_for_each_entry(udc, &udc_list, list) {
328 /* For now we take the first one */
333 pr_debug("couldn't find an available UDC\n");
334 mutex_unlock(&udc_lock);
337 ret = udc_bind_to_driver(udc, driver);
338 mutex_unlock(&udc_lock);
341 EXPORT_SYMBOL_GPL(usb_gadget_probe_driver);
343 int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
345 struct usb_udc *udc = NULL;
348 if (!driver || !driver->unbind)
351 mutex_lock(&udc_lock);
352 list_for_each_entry(udc, &udc_list, list)
353 if (udc->driver == driver) {
354 usb_gadget_remove_driver(udc);
359 mutex_unlock(&udc_lock);
362 EXPORT_SYMBOL_GPL(usb_gadget_unregister_driver);
364 /* ------------------------------------------------------------------------- */
366 static ssize_t usb_udc_srp_store(struct device *dev,
367 struct device_attribute *attr, const char *buf, size_t n)
369 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
371 if (sysfs_streq(buf, "1"))
372 usb_gadget_wakeup(udc->gadget);
376 static DEVICE_ATTR(srp, S_IWUSR, NULL, usb_udc_srp_store);
378 static ssize_t usb_udc_softconn_store(struct device *dev,
379 struct device_attribute *attr, const char *buf, size_t n)
381 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
383 if (sysfs_streq(buf, "connect")) {
384 usb_gadget_udc_start(udc->gadget, udc->driver);
385 usb_gadget_connect(udc->gadget);
386 } else if (sysfs_streq(buf, "disconnect")) {
387 usb_gadget_disconnect(udc->gadget);
388 usb_gadget_udc_stop(udc->gadget, udc->driver);
390 dev_err(dev, "unsupported command '%s'\n", buf);
396 static DEVICE_ATTR(soft_connect, S_IWUSR, NULL, usb_udc_softconn_store);
398 #define USB_UDC_SPEED_ATTR(name, param) \
399 ssize_t usb_udc_##param##_show(struct device *dev, \
400 struct device_attribute *attr, char *buf) \
402 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
403 return snprintf(buf, PAGE_SIZE, "%s\n", \
404 usb_speed_string(udc->gadget->param)); \
406 static DEVICE_ATTR(name, S_IRUSR, usb_udc_##param##_show, NULL)
408 static USB_UDC_SPEED_ATTR(current_speed, speed);
409 static USB_UDC_SPEED_ATTR(maximum_speed, max_speed);
411 #define USB_UDC_ATTR(name) \
412 ssize_t usb_udc_##name##_show(struct device *dev, \
413 struct device_attribute *attr, char *buf) \
415 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
416 struct usb_gadget *gadget = udc->gadget; \
418 return snprintf(buf, PAGE_SIZE, "%d\n", gadget->name); \
420 static DEVICE_ATTR(name, S_IRUGO, usb_udc_##name##_show, NULL)
422 static USB_UDC_ATTR(is_otg);
423 static USB_UDC_ATTR(is_a_peripheral);
424 static USB_UDC_ATTR(b_hnp_enable);
425 static USB_UDC_ATTR(a_hnp_support);
426 static USB_UDC_ATTR(a_alt_hnp_support);
428 static struct attribute *usb_udc_attrs[] = {
430 &dev_attr_soft_connect.attr,
431 &dev_attr_current_speed.attr,
432 &dev_attr_maximum_speed.attr,
434 &dev_attr_is_otg.attr,
435 &dev_attr_is_a_peripheral.attr,
436 &dev_attr_b_hnp_enable.attr,
437 &dev_attr_a_hnp_support.attr,
438 &dev_attr_a_alt_hnp_support.attr,
442 static const struct attribute_group usb_udc_attr_group = {
443 .attrs = usb_udc_attrs,
446 static const struct attribute_group *usb_udc_attr_groups[] = {
451 static int usb_udc_uevent(struct device *dev, struct kobj_uevent_env *env)
453 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
456 ret = add_uevent_var(env, "USB_UDC_NAME=%s", udc->gadget->name);
458 dev_err(dev, "failed to add uevent USB_UDC_NAME\n");
463 ret = add_uevent_var(env, "USB_UDC_DRIVER=%s",
464 udc->driver->function);
466 dev_err(dev, "failed to add uevent USB_UDC_DRIVER\n");
474 static int __init usb_udc_init(void)
476 udc_class = class_create(THIS_MODULE, "udc");
477 if (IS_ERR(udc_class)) {
478 pr_err("failed to create udc class --> %ld\n",
480 return PTR_ERR(udc_class);
483 udc_class->dev_uevent = usb_udc_uevent;
486 subsys_initcall(usb_udc_init);
488 static void __exit usb_udc_exit(void)
490 class_destroy(udc_class);
492 module_exit(usb_udc_exit);
494 MODULE_DESCRIPTION("UDC Framework");
495 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
496 MODULE_LICENSE("GPL v2");