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
, NULL
);
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");