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 * @udc: The UDC to be started
179 * This call is issued by the UDC Class driver when it's about
180 * to register a gadget driver to the device controller, before
181 * calling gadget driver's bind() method.
183 * It allows the controller to be powered off until strictly
184 * necessary to have it powered on.
186 * Returns zero on success, else negative errno.
188 static inline int usb_gadget_udc_start(struct usb_udc
*udc
)
190 return udc
->gadget
->ops
->udc_start(udc
->gadget
, udc
->driver
);
194 * usb_gadget_udc_stop - tells usb device controller we don't need it anymore
195 * @gadget: The device we want to stop activity
196 * @driver: The driver to unbind from @gadget
198 * This call is issued by the UDC Class driver after calling
199 * gadget driver's unbind() method.
201 * The details are implementation specific, but it can go as
202 * far as powering off UDC completely and disable its data
205 static inline void usb_gadget_udc_stop(struct usb_udc
*udc
)
207 udc
->gadget
->ops
->udc_stop(udc
->gadget
);
211 * usb_udc_release - release the usb_udc struct
212 * @dev: the dev member within usb_udc
214 * This is called by driver's core in order to free memory once the last
215 * reference is released.
217 static void usb_udc_release(struct device
*dev
)
221 udc
= container_of(dev
, struct usb_udc
, dev
);
222 dev_dbg(dev
, "releasing '%s'\n", dev_name(dev
));
226 static const struct attribute_group
*usb_udc_attr_groups
[];
228 static void usb_udc_nop_release(struct device
*dev
)
230 dev_vdbg(dev
, "%s\n", __func__
);
234 * usb_add_gadget_udc_release - adds a new gadget to the udc class driver list
235 * @parent: the parent device to this udc. Usually the controller driver's
237 * @gadget: the gadget to be added to the list.
238 * @release: a gadget release function.
240 * Returns zero on success, negative errno otherwise.
242 int usb_add_gadget_udc_release(struct device
*parent
, struct usb_gadget
*gadget
,
243 void (*release
)(struct device
*dev
))
248 udc
= kzalloc(sizeof(*udc
), GFP_KERNEL
);
252 dev_set_name(&gadget
->dev
, "gadget");
253 INIT_WORK(&gadget
->work
, usb_gadget_state_work
);
254 gadget
->dev
.parent
= parent
;
256 #ifdef CONFIG_HAS_DMA
257 dma_set_coherent_mask(&gadget
->dev
, parent
->coherent_dma_mask
);
258 gadget
->dev
.dma_parms
= parent
->dma_parms
;
259 gadget
->dev
.dma_mask
= parent
->dma_mask
;
263 gadget
->dev
.release
= release
;
265 gadget
->dev
.release
= usb_udc_nop_release
;
267 ret
= device_register(&gadget
->dev
);
271 device_initialize(&udc
->dev
);
272 udc
->dev
.release
= usb_udc_release
;
273 udc
->dev
.class = udc_class
;
274 udc
->dev
.groups
= usb_udc_attr_groups
;
275 udc
->dev
.parent
= parent
;
276 ret
= dev_set_name(&udc
->dev
, "%s", kobject_name(&parent
->kobj
));
280 udc
->gadget
= gadget
;
282 mutex_lock(&udc_lock
);
283 list_add_tail(&udc
->list
, &udc_list
);
285 ret
= device_add(&udc
->dev
);
289 usb_gadget_set_state(gadget
, USB_STATE_NOTATTACHED
);
291 mutex_unlock(&udc_lock
);
296 list_del(&udc
->list
);
297 mutex_unlock(&udc_lock
);
300 put_device(&udc
->dev
);
303 put_device(&gadget
->dev
);
309 EXPORT_SYMBOL_GPL(usb_add_gadget_udc_release
);
312 * usb_add_gadget_udc - adds a new gadget to the udc class driver list
313 * @parent: the parent device to this udc. Usually the controller
315 * @gadget: the gadget to be added to the list
317 * Returns zero on success, negative errno otherwise.
319 int usb_add_gadget_udc(struct device
*parent
, struct usb_gadget
*gadget
)
321 return usb_add_gadget_udc_release(parent
, gadget
, NULL
);
323 EXPORT_SYMBOL_GPL(usb_add_gadget_udc
);
325 static void usb_gadget_remove_driver(struct usb_udc
*udc
)
327 dev_dbg(&udc
->dev
, "unregistering UDC driver [%s]\n",
328 udc
->driver
->function
);
330 kobject_uevent(&udc
->dev
.kobj
, KOBJ_CHANGE
);
332 usb_gadget_disconnect(udc
->gadget
);
333 udc
->driver
->disconnect(udc
->gadget
);
334 udc
->driver
->unbind(udc
->gadget
);
335 usb_gadget_udc_stop(udc
);
338 udc
->dev
.driver
= NULL
;
339 udc
->gadget
->dev
.driver
= NULL
;
343 * usb_del_gadget_udc - deletes @udc from udc_list
344 * @gadget: the gadget to be removed.
346 * This, will call usb_gadget_unregister_driver() if
347 * the @udc is still busy.
349 void usb_del_gadget_udc(struct usb_gadget
*gadget
)
351 struct usb_udc
*udc
= NULL
;
353 mutex_lock(&udc_lock
);
354 list_for_each_entry(udc
, &udc_list
, list
)
355 if (udc
->gadget
== gadget
)
358 dev_err(gadget
->dev
.parent
, "gadget not registered.\n");
359 mutex_unlock(&udc_lock
);
364 dev_vdbg(gadget
->dev
.parent
, "unregistering gadget\n");
366 list_del(&udc
->list
);
367 mutex_unlock(&udc_lock
);
370 usb_gadget_remove_driver(udc
);
372 kobject_uevent(&udc
->dev
.kobj
, KOBJ_REMOVE
);
373 flush_work(&gadget
->work
);
374 device_unregister(&udc
->dev
);
375 device_unregister(&gadget
->dev
);
377 EXPORT_SYMBOL_GPL(usb_del_gadget_udc
);
379 /* ------------------------------------------------------------------------- */
381 static int udc_bind_to_driver(struct usb_udc
*udc
, struct usb_gadget_driver
*driver
)
385 dev_dbg(&udc
->dev
, "registering UDC driver [%s]\n",
388 udc
->driver
= driver
;
389 udc
->dev
.driver
= &driver
->driver
;
390 udc
->gadget
->dev
.driver
= &driver
->driver
;
392 ret
= driver
->bind(udc
->gadget
, driver
);
395 ret
= usb_gadget_udc_start(udc
);
397 driver
->unbind(udc
->gadget
);
400 usb_gadget_connect(udc
->gadget
);
402 kobject_uevent(&udc
->dev
.kobj
, KOBJ_CHANGE
);
406 dev_err(&udc
->dev
, "failed to start %s: %d\n",
407 udc
->driver
->function
, ret
);
409 udc
->dev
.driver
= NULL
;
410 udc
->gadget
->dev
.driver
= NULL
;
414 int usb_udc_attach_driver(const char *name
, struct usb_gadget_driver
*driver
)
416 struct usb_udc
*udc
= NULL
;
419 mutex_lock(&udc_lock
);
420 list_for_each_entry(udc
, &udc_list
, list
) {
421 ret
= strcmp(name
, dev_name(&udc
->dev
));
433 ret
= udc_bind_to_driver(udc
, driver
);
435 mutex_unlock(&udc_lock
);
438 EXPORT_SYMBOL_GPL(usb_udc_attach_driver
);
440 int usb_gadget_probe_driver(struct usb_gadget_driver
*driver
)
442 struct usb_udc
*udc
= NULL
;
445 if (!driver
|| !driver
->bind
|| !driver
->setup
)
448 mutex_lock(&udc_lock
);
449 list_for_each_entry(udc
, &udc_list
, list
) {
450 /* For now we take the first one */
455 pr_debug("couldn't find an available UDC\n");
456 mutex_unlock(&udc_lock
);
459 ret
= udc_bind_to_driver(udc
, driver
);
460 mutex_unlock(&udc_lock
);
463 EXPORT_SYMBOL_GPL(usb_gadget_probe_driver
);
465 int usb_gadget_unregister_driver(struct usb_gadget_driver
*driver
)
467 struct usb_udc
*udc
= NULL
;
470 if (!driver
|| !driver
->unbind
)
473 mutex_lock(&udc_lock
);
474 list_for_each_entry(udc
, &udc_list
, list
)
475 if (udc
->driver
== driver
) {
476 usb_gadget_remove_driver(udc
);
477 usb_gadget_set_state(udc
->gadget
,
478 USB_STATE_NOTATTACHED
);
483 mutex_unlock(&udc_lock
);
486 EXPORT_SYMBOL_GPL(usb_gadget_unregister_driver
);
488 /* ------------------------------------------------------------------------- */
490 static ssize_t
usb_udc_srp_store(struct device
*dev
,
491 struct device_attribute
*attr
, const char *buf
, size_t n
)
493 struct usb_udc
*udc
= container_of(dev
, struct usb_udc
, dev
);
495 if (sysfs_streq(buf
, "1"))
496 usb_gadget_wakeup(udc
->gadget
);
500 static DEVICE_ATTR(srp
, S_IWUSR
, NULL
, usb_udc_srp_store
);
502 static ssize_t
usb_udc_softconn_store(struct device
*dev
,
503 struct device_attribute
*attr
, const char *buf
, size_t n
)
505 struct usb_udc
*udc
= container_of(dev
, struct usb_udc
, dev
);
508 dev_err(dev
, "soft-connect without a gadget driver\n");
512 if (sysfs_streq(buf
, "connect")) {
513 usb_gadget_udc_start(udc
);
514 usb_gadget_connect(udc
->gadget
);
515 } else if (sysfs_streq(buf
, "disconnect")) {
516 usb_gadget_disconnect(udc
->gadget
);
517 udc
->driver
->disconnect(udc
->gadget
);
518 usb_gadget_udc_stop(udc
);
520 dev_err(dev
, "unsupported command '%s'\n", buf
);
526 static DEVICE_ATTR(soft_connect
, S_IWUSR
, NULL
, usb_udc_softconn_store
);
528 static ssize_t
state_show(struct device
*dev
, struct device_attribute
*attr
,
531 struct usb_udc
*udc
= container_of(dev
, struct usb_udc
, dev
);
532 struct usb_gadget
*gadget
= udc
->gadget
;
534 return sprintf(buf
, "%s\n", usb_state_string(gadget
->state
));
536 static DEVICE_ATTR_RO(state
);
538 #define USB_UDC_SPEED_ATTR(name, param) \
539 ssize_t name##_show(struct device *dev, \
540 struct device_attribute *attr, char *buf) \
542 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
543 return snprintf(buf, PAGE_SIZE, "%s\n", \
544 usb_speed_string(udc->gadget->param)); \
546 static DEVICE_ATTR_RO(name)
548 static USB_UDC_SPEED_ATTR(current_speed
, speed
);
549 static USB_UDC_SPEED_ATTR(maximum_speed
, max_speed
);
551 #define USB_UDC_ATTR(name) \
552 ssize_t name##_show(struct device *dev, \
553 struct device_attribute *attr, char *buf) \
555 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
556 struct usb_gadget *gadget = udc->gadget; \
558 return snprintf(buf, PAGE_SIZE, "%d\n", gadget->name); \
560 static DEVICE_ATTR_RO(name)
562 static USB_UDC_ATTR(is_otg
);
563 static USB_UDC_ATTR(is_a_peripheral
);
564 static USB_UDC_ATTR(b_hnp_enable
);
565 static USB_UDC_ATTR(a_hnp_support
);
566 static USB_UDC_ATTR(a_alt_hnp_support
);
567 static USB_UDC_ATTR(is_selfpowered
);
569 static struct attribute
*usb_udc_attrs
[] = {
571 &dev_attr_soft_connect
.attr
,
572 &dev_attr_state
.attr
,
573 &dev_attr_current_speed
.attr
,
574 &dev_attr_maximum_speed
.attr
,
576 &dev_attr_is_otg
.attr
,
577 &dev_attr_is_a_peripheral
.attr
,
578 &dev_attr_b_hnp_enable
.attr
,
579 &dev_attr_a_hnp_support
.attr
,
580 &dev_attr_a_alt_hnp_support
.attr
,
581 &dev_attr_is_selfpowered
.attr
,
585 static const struct attribute_group usb_udc_attr_group
= {
586 .attrs
= usb_udc_attrs
,
589 static const struct attribute_group
*usb_udc_attr_groups
[] = {
594 static int usb_udc_uevent(struct device
*dev
, struct kobj_uevent_env
*env
)
596 struct usb_udc
*udc
= container_of(dev
, struct usb_udc
, dev
);
599 ret
= add_uevent_var(env
, "USB_UDC_NAME=%s", udc
->gadget
->name
);
601 dev_err(dev
, "failed to add uevent USB_UDC_NAME\n");
606 ret
= add_uevent_var(env
, "USB_UDC_DRIVER=%s",
607 udc
->driver
->function
);
609 dev_err(dev
, "failed to add uevent USB_UDC_DRIVER\n");
617 static int __init
usb_udc_init(void)
619 udc_class
= class_create(THIS_MODULE
, "udc");
620 if (IS_ERR(udc_class
)) {
621 pr_err("failed to create udc class --> %ld\n",
623 return PTR_ERR(udc_class
);
626 udc_class
->dev_uevent
= usb_udc_uevent
;
629 subsys_initcall(usb_udc_init
);
631 static void __exit
usb_udc_exit(void)
633 class_destroy(udc_class
);
635 module_exit(usb_udc_exit
);
637 MODULE_DESCRIPTION("UDC Framework");
638 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
639 MODULE_LICENSE("GPL v2");