4 * (C) Copyright Linus Torvalds 1999
5 * (C) Copyright Johannes Erdfelt 1999-2001
6 * (C) Copyright Andreas Gal 1999
7 * (C) Copyright Gregory P. Smith 1999
8 * (C) Copyright Deti Fliegl 1999 (new USB architecture)
9 * (C) Copyright Randy Dunlap 2000
10 * (C) Copyright David Brownell 2000-2004
11 * (C) Copyright Yggdrasil Computing, Inc. 2000
12 * (usb_device_id matching changes by Adam J. Richter)
13 * (C) Copyright Greg Kroah-Hartman 2002-2003
15 * NOTE! This is not actually a driver at all, rather this is
16 * just a collection of helper routines that implement the
17 * generic USB things that the real drivers can use..
19 * Think of this as a "USB library" rather than anything else.
20 * It should be considered a slave, with no callbacks. Callbacks
24 #include <linux/module.h>
25 #include <linux/string.h>
26 #include <linux/bitops.h>
27 #include <linux/slab.h>
28 #include <linux/interrupt.h> /* for in_interrupt() */
29 #include <linux/kmod.h>
30 #include <linux/init.h>
31 #include <linux/spinlock.h>
32 #include <linux/errno.h>
33 #include <linux/smp_lock.h>
34 #include <linux/usb.h>
35 #include <linux/mutex.h>
38 #include <asm/scatterlist.h>
40 #include <linux/dma-mapping.h>
46 const char *usbcore_name
= "usbcore";
48 static int nousb
; /* Disable USB when built into kernel image */
52 * usb_ifnum_to_if - get the interface object with a given interface number
53 * @dev: the device whose current configuration is considered
54 * @ifnum: the desired interface
56 * This walks the device descriptor for the currently active configuration
57 * and returns a pointer to the interface with that particular interface
60 * Note that configuration descriptors are not required to assign interface
61 * numbers sequentially, so that it would be incorrect to assume that
62 * the first interface in that descriptor corresponds to interface zero.
63 * This routine helps device drivers avoid such mistakes.
64 * However, you should make sure that you do the right thing with any
65 * alternate settings available for this interfaces.
67 * Don't call this function unless you are bound to one of the interfaces
68 * on this device or you have locked the device!
70 struct usb_interface
*usb_ifnum_to_if(const struct usb_device
*dev
,
73 struct usb_host_config
*config
= dev
->actconfig
;
78 for (i
= 0; i
< config
->desc
.bNumInterfaces
; i
++)
79 if (config
->interface
[i
]->altsetting
[0]
80 .desc
.bInterfaceNumber
== ifnum
)
81 return config
->interface
[i
];
87 * usb_altnum_to_altsetting - get the altsetting structure with a given
88 * alternate setting number.
89 * @intf: the interface containing the altsetting in question
90 * @altnum: the desired alternate setting number
92 * This searches the altsetting array of the specified interface for
93 * an entry with the correct bAlternateSetting value and returns a pointer
94 * to that entry, or null.
96 * Note that altsettings need not be stored sequentially by number, so
97 * it would be incorrect to assume that the first altsetting entry in
98 * the array corresponds to altsetting zero. This routine helps device
99 * drivers avoid such mistakes.
101 * Don't call this function unless you are bound to the intf interface
102 * or you have locked the device!
104 struct usb_host_interface
*usb_altnum_to_altsetting(const struct usb_interface
*intf
,
109 for (i
= 0; i
< intf
->num_altsetting
; i
++) {
110 if (intf
->altsetting
[i
].desc
.bAlternateSetting
== altnum
)
111 return &intf
->altsetting
[i
];
116 struct find_interface_arg
{
118 struct usb_interface
*interface
;
121 static int __find_interface(struct device
* dev
, void * data
)
123 struct find_interface_arg
*arg
= data
;
124 struct usb_interface
*intf
;
126 /* can't look at usb devices, only interfaces */
127 if (is_usb_device(dev
))
130 intf
= to_usb_interface(dev
);
131 if (intf
->minor
!= -1 && intf
->minor
== arg
->minor
) {
132 arg
->interface
= intf
;
139 * usb_find_interface - find usb_interface pointer for driver and device
140 * @drv: the driver whose current configuration is considered
141 * @minor: the minor number of the desired device
143 * This walks the driver device list and returns a pointer to the interface
144 * with the matching minor. Note, this only works for devices that share the
147 struct usb_interface
*usb_find_interface(struct usb_driver
*drv
, int minor
)
149 struct find_interface_arg argb
;
152 argb
.interface
= NULL
;
153 driver_for_each_device(&drv
->drvwrap
.driver
, NULL
, &argb
,
155 return argb
.interface
;
159 * usb_release_dev - free a usb device structure when all users of it are finished.
160 * @dev: device that's been disconnected
162 * Will be called only by the device core when all users of this usb device are
165 static void usb_release_dev(struct device
*dev
)
167 struct usb_device
*udev
;
169 udev
= to_usb_device(dev
);
171 usb_destroy_configuration(udev
);
172 usb_bus_put(udev
->bus
);
173 kfree(udev
->product
);
174 kfree(udev
->manufacturer
);
180 * usb_alloc_dev - usb device constructor (usbcore-internal)
181 * @parent: hub to which device is connected; null to allocate a root hub
182 * @bus: bus used to access the device
183 * @port1: one-based index of port; ignored for root hubs
184 * Context: !in_interrupt ()
186 * Only hub drivers (including virtual root hub drivers for host
187 * controllers) should ever call this.
189 * This call may not be used in a non-sleeping context.
192 usb_alloc_dev(struct usb_device
*parent
, struct usb_bus
*bus
, unsigned port1
)
194 struct usb_device
*dev
;
196 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
200 bus
= usb_bus_get(bus
);
206 device_initialize(&dev
->dev
);
207 dev
->dev
.bus
= &usb_bus_type
;
208 dev
->dev
.dma_mask
= bus
->controller
->dma_mask
;
209 dev
->dev
.release
= usb_release_dev
;
210 dev
->state
= USB_STATE_ATTACHED
;
212 /* This magic assignment distinguishes devices from interfaces */
213 dev
->dev
.platform_data
= &usb_generic_driver
;
215 INIT_LIST_HEAD(&dev
->ep0
.urb_list
);
216 dev
->ep0
.desc
.bLength
= USB_DT_ENDPOINT_SIZE
;
217 dev
->ep0
.desc
.bDescriptorType
= USB_DT_ENDPOINT
;
218 /* ep0 maxpacket comes later, from device descriptor */
219 dev
->ep_in
[0] = dev
->ep_out
[0] = &dev
->ep0
;
221 /* Save readable and stable topology id, distinguishing devices
222 * by location for diagnostics, tools, driver model, etc. The
223 * string is a path along hub ports, from the root. Each device's
224 * dev->devpath will be stable until USB is re-cabled, and hubs
225 * are often labeled with these port numbers. The bus_id isn't
226 * as stable: bus->busnum changes easily from modprobe order,
227 * cardbus or pci hotplugging, and so on.
229 if (unlikely (!parent
)) {
230 dev
->devpath
[0] = '0';
232 dev
->dev
.parent
= bus
->controller
;
233 sprintf (&dev
->dev
.bus_id
[0], "usb%d", bus
->busnum
);
235 /* match any labeling on the hubs; it's one-based */
236 if (parent
->devpath
[0] == '0')
237 snprintf (dev
->devpath
, sizeof dev
->devpath
,
240 snprintf (dev
->devpath
, sizeof dev
->devpath
,
241 "%s.%d", parent
->devpath
, port1
);
243 dev
->dev
.parent
= &parent
->dev
;
244 sprintf (&dev
->dev
.bus_id
[0], "%d-%s",
245 bus
->busnum
, dev
->devpath
);
247 /* hub driver sets up TT records */
250 dev
->portnum
= port1
;
252 dev
->parent
= parent
;
253 INIT_LIST_HEAD(&dev
->filelist
);
259 * usb_get_dev - increments the reference count of the usb device structure
260 * @dev: the device being referenced
262 * Each live reference to a device should be refcounted.
264 * Drivers for USB interfaces should normally record such references in
265 * their probe() methods, when they bind to an interface, and release
266 * them by calling usb_put_dev(), in their disconnect() methods.
268 * A pointer to the device with the incremented reference counter is returned.
270 struct usb_device
*usb_get_dev(struct usb_device
*dev
)
273 get_device(&dev
->dev
);
278 * usb_put_dev - release a use of the usb device structure
279 * @dev: device that's been disconnected
281 * Must be called when a user of a device is finished with it. When the last
282 * user of the device calls this function, the memory of the device is freed.
284 void usb_put_dev(struct usb_device
*dev
)
287 put_device(&dev
->dev
);
291 * usb_get_intf - increments the reference count of the usb interface structure
292 * @intf: the interface being referenced
294 * Each live reference to a interface must be refcounted.
296 * Drivers for USB interfaces should normally record such references in
297 * their probe() methods, when they bind to an interface, and release
298 * them by calling usb_put_intf(), in their disconnect() methods.
300 * A pointer to the interface with the incremented reference counter is
303 struct usb_interface
*usb_get_intf(struct usb_interface
*intf
)
306 get_device(&intf
->dev
);
311 * usb_put_intf - release a use of the usb interface structure
312 * @intf: interface that's been decremented
314 * Must be called when a user of an interface is finished with it. When the
315 * last user of the interface calls this function, the memory of the interface
318 void usb_put_intf(struct usb_interface
*intf
)
321 put_device(&intf
->dev
);
325 /* USB device locking
327 * USB devices and interfaces are locked using the semaphore in their
328 * embedded struct device. The hub driver guarantees that whenever a
329 * device is connected or disconnected, drivers are called with the
330 * USB device locked as well as their particular interface.
332 * Complications arise when several devices are to be locked at the same
333 * time. Only hub-aware drivers that are part of usbcore ever have to
334 * do this; nobody else needs to worry about it. The rule for locking
337 * When locking both a device and its parent, always lock the
342 * usb_lock_device_for_reset - cautiously acquire the lock for a
343 * usb device structure
344 * @udev: device that's being locked
345 * @iface: interface bound to the driver making the request (optional)
347 * Attempts to acquire the device lock, but fails if the device is
348 * NOTATTACHED or SUSPENDED, or if iface is specified and the interface
349 * is neither BINDING nor BOUND. Rather than sleeping to wait for the
350 * lock, the routine polls repeatedly. This is to prevent deadlock with
351 * disconnect; in some drivers (such as usb-storage) the disconnect()
352 * or suspend() method will block waiting for a device reset to complete.
354 * Returns a negative error code for failure, otherwise 1 or 0 to indicate
355 * that the device will or will not have to be unlocked. (0 can be
356 * returned when an interface is given and is BINDING, because in that
357 * case the driver already owns the device lock.)
359 int usb_lock_device_for_reset(struct usb_device
*udev
,
360 const struct usb_interface
*iface
)
362 unsigned long jiffies_expire
= jiffies
+ HZ
;
364 if (udev
->state
== USB_STATE_NOTATTACHED
)
366 if (udev
->state
== USB_STATE_SUSPENDED
)
367 return -EHOSTUNREACH
;
369 switch (iface
->condition
) {
370 case USB_INTERFACE_BINDING
:
372 case USB_INTERFACE_BOUND
:
379 while (usb_trylock_device(udev
) != 0) {
381 /* If we can't acquire the lock after waiting one second,
382 * we're probably deadlocked */
383 if (time_after(jiffies
, jiffies_expire
))
387 if (udev
->state
== USB_STATE_NOTATTACHED
)
389 if (udev
->state
== USB_STATE_SUSPENDED
)
390 return -EHOSTUNREACH
;
391 if (iface
&& iface
->condition
!= USB_INTERFACE_BOUND
)
398 static struct usb_device
*match_device(struct usb_device
*dev
,
399 u16 vendor_id
, u16 product_id
)
401 struct usb_device
*ret_dev
= NULL
;
404 dev_dbg(&dev
->dev
, "check for vendor %04x, product %04x ...\n",
405 le16_to_cpu(dev
->descriptor
.idVendor
),
406 le16_to_cpu(dev
->descriptor
.idProduct
));
408 /* see if this device matches */
409 if ((vendor_id
== le16_to_cpu(dev
->descriptor
.idVendor
)) &&
410 (product_id
== le16_to_cpu(dev
->descriptor
.idProduct
))) {
411 dev_dbg (&dev
->dev
, "matched this device!\n");
412 ret_dev
= usb_get_dev(dev
);
416 /* look through all of the children of this device */
417 for (child
= 0; child
< dev
->maxchild
; ++child
) {
418 if (dev
->children
[child
]) {
419 usb_lock_device(dev
->children
[child
]);
420 ret_dev
= match_device(dev
->children
[child
],
421 vendor_id
, product_id
);
422 usb_unlock_device(dev
->children
[child
]);
432 * usb_find_device - find a specific usb device in the system
433 * @vendor_id: the vendor id of the device to find
434 * @product_id: the product id of the device to find
436 * Returns a pointer to a struct usb_device if such a specified usb
437 * device is present in the system currently. The usage count of the
438 * device will be incremented if a device is found. Make sure to call
439 * usb_put_dev() when the caller is finished with the device.
441 * If a device with the specified vendor and product id is not found,
444 struct usb_device
*usb_find_device(u16 vendor_id
, u16 product_id
)
446 struct list_head
*buslist
;
448 struct usb_device
*dev
= NULL
;
450 mutex_lock(&usb_bus_list_lock
);
451 for (buslist
= usb_bus_list
.next
;
452 buslist
!= &usb_bus_list
;
453 buslist
= buslist
->next
) {
454 bus
= container_of(buslist
, struct usb_bus
, bus_list
);
457 usb_lock_device(bus
->root_hub
);
458 dev
= match_device(bus
->root_hub
, vendor_id
, product_id
);
459 usb_unlock_device(bus
->root_hub
);
464 mutex_unlock(&usb_bus_list_lock
);
469 * usb_get_current_frame_number - return current bus frame number
470 * @dev: the device whose bus is being queried
472 * Returns the current frame number for the USB host controller
473 * used with the given USB device. This can be used when scheduling
474 * isochronous requests.
476 * Note that different kinds of host controller have different
477 * "scheduling horizons". While one type might support scheduling only
478 * 32 frames into the future, others could support scheduling up to
479 * 1024 frames into the future.
481 int usb_get_current_frame_number(struct usb_device
*dev
)
483 return dev
->bus
->op
->get_frame_number (dev
);
487 * usb_endpoint_dir_in - check if the endpoint has IN direction
488 * @epd: endpoint to be checked
490 * Returns true if the endpoint is of type IN, otherwise it returns false.
492 int usb_endpoint_dir_in(const struct usb_endpoint_descriptor
*epd
)
494 return ((epd
->bEndpointAddress
& USB_ENDPOINT_DIR_MASK
) == USB_DIR_IN
);
498 * usb_endpoint_dir_out - check if the endpoint has OUT direction
499 * @epd: endpoint to be checked
501 * Returns true if the endpoint is of type OUT, otherwise it returns false.
503 int usb_endpoint_dir_out(const struct usb_endpoint_descriptor
*epd
)
505 return ((epd
->bEndpointAddress
& USB_ENDPOINT_DIR_MASK
) == USB_DIR_OUT
);
509 * usb_endpoint_xfer_bulk - check if the endpoint has bulk transfer type
510 * @epd: endpoint to be checked
512 * Returns true if the endpoint is of type bulk, otherwise it returns false.
514 int usb_endpoint_xfer_bulk(const struct usb_endpoint_descriptor
*epd
)
516 return ((epd
->bmAttributes
& USB_ENDPOINT_XFERTYPE_MASK
) ==
517 USB_ENDPOINT_XFER_BULK
);
521 * usb_endpoint_xfer_int - check if the endpoint has interrupt transfer type
522 * @epd: endpoint to be checked
524 * Returns true if the endpoint is of type interrupt, otherwise it returns
527 int usb_endpoint_xfer_int(const struct usb_endpoint_descriptor
*epd
)
529 return ((epd
->bmAttributes
& USB_ENDPOINT_XFERTYPE_MASK
) ==
530 USB_ENDPOINT_XFER_INT
);
534 * usb_endpoint_xfer_isoc - check if the endpoint has isochronous transfer type
535 * @epd: endpoint to be checked
537 * Returns true if the endpoint is of type isochronous, otherwise it returns
540 int usb_endpoint_xfer_isoc(const struct usb_endpoint_descriptor
*epd
)
542 return ((epd
->bmAttributes
& USB_ENDPOINT_XFERTYPE_MASK
) ==
543 USB_ENDPOINT_XFER_ISOC
);
547 * usb_endpoint_is_bulk_in - check if the endpoint is bulk IN
548 * @epd: endpoint to be checked
550 * Returns true if the endpoint has bulk transfer type and IN direction,
551 * otherwise it returns false.
553 int usb_endpoint_is_bulk_in(const struct usb_endpoint_descriptor
*epd
)
555 return (usb_endpoint_xfer_bulk(epd
) && usb_endpoint_dir_in(epd
));
559 * usb_endpoint_is_bulk_out - check if the endpoint is bulk OUT
560 * @epd: endpoint to be checked
562 * Returns true if the endpoint has bulk transfer type and OUT direction,
563 * otherwise it returns false.
565 int usb_endpoint_is_bulk_out(const struct usb_endpoint_descriptor
*epd
)
567 return (usb_endpoint_xfer_bulk(epd
) && usb_endpoint_dir_out(epd
));
571 * usb_endpoint_is_int_in - check if the endpoint is interrupt IN
572 * @epd: endpoint to be checked
574 * Returns true if the endpoint has interrupt transfer type and IN direction,
575 * otherwise it returns false.
577 int usb_endpoint_is_int_in(const struct usb_endpoint_descriptor
*epd
)
579 return (usb_endpoint_xfer_int(epd
) && usb_endpoint_dir_in(epd
));
583 * usb_endpoint_is_int_out - check if the endpoint is interrupt OUT
584 * @epd: endpoint to be checked
586 * Returns true if the endpoint has interrupt transfer type and OUT direction,
587 * otherwise it returns false.
589 int usb_endpoint_is_int_out(const struct usb_endpoint_descriptor
*epd
)
591 return (usb_endpoint_xfer_int(epd
) && usb_endpoint_dir_out(epd
));
595 * usb_endpoint_is_isoc_in - check if the endpoint is isochronous IN
596 * @epd: endpoint to be checked
598 * Returns true if the endpoint has isochronous transfer type and IN direction,
599 * otherwise it returns false.
601 int usb_endpoint_is_isoc_in(const struct usb_endpoint_descriptor
*epd
)
603 return (usb_endpoint_xfer_isoc(epd
) && usb_endpoint_dir_in(epd
));
607 * usb_endpoint_is_isoc_out - check if the endpoint is isochronous OUT
608 * @epd: endpoint to be checked
610 * Returns true if the endpoint has isochronous transfer type and OUT direction,
611 * otherwise it returns false.
613 int usb_endpoint_is_isoc_out(const struct usb_endpoint_descriptor
*epd
)
615 return (usb_endpoint_xfer_isoc(epd
) && usb_endpoint_dir_out(epd
));
618 /*-------------------------------------------------------------------*/
620 * __usb_get_extra_descriptor() finds a descriptor of specific type in the
621 * extra field of the interface and endpoint descriptor structs.
624 int __usb_get_extra_descriptor(char *buffer
, unsigned size
,
625 unsigned char type
, void **ptr
)
627 struct usb_descriptor_header
*header
;
629 while (size
>= sizeof(struct usb_descriptor_header
)) {
630 header
= (struct usb_descriptor_header
*)buffer
;
632 if (header
->bLength
< 2) {
634 "%s: bogus descriptor, type %d length %d\n",
636 header
->bDescriptorType
,
641 if (header
->bDescriptorType
== type
) {
646 buffer
+= header
->bLength
;
647 size
-= header
->bLength
;
653 * usb_buffer_alloc - allocate dma-consistent buffer for URB_NO_xxx_DMA_MAP
654 * @dev: device the buffer will be used with
655 * @size: requested buffer size
656 * @mem_flags: affect whether allocation may block
657 * @dma: used to return DMA address of buffer
659 * Return value is either null (indicating no buffer could be allocated), or
660 * the cpu-space pointer to a buffer that may be used to perform DMA to the
661 * specified device. Such cpu-space buffers are returned along with the DMA
662 * address (through the pointer provided).
664 * These buffers are used with URB_NO_xxx_DMA_MAP set in urb->transfer_flags
665 * to avoid behaviors like using "DMA bounce buffers", or tying down I/O
666 * mapping hardware for long idle periods. The implementation varies between
667 * platforms, depending on details of how DMA will work to this device.
668 * Using these buffers also helps prevent cacheline sharing problems on
669 * architectures where CPU caches are not DMA-coherent.
671 * When the buffer is no longer used, free it with usb_buffer_free().
673 void *usb_buffer_alloc (
674 struct usb_device
*dev
,
680 if (!dev
|| !dev
->bus
|| !dev
->bus
->op
|| !dev
->bus
->op
->buffer_alloc
)
682 return dev
->bus
->op
->buffer_alloc (dev
->bus
, size
, mem_flags
, dma
);
686 * usb_buffer_free - free memory allocated with usb_buffer_alloc()
687 * @dev: device the buffer was used with
688 * @size: requested buffer size
689 * @addr: CPU address of buffer
690 * @dma: DMA address of buffer
692 * This reclaims an I/O buffer, letting it be reused. The memory must have
693 * been allocated using usb_buffer_alloc(), and the parameters must match
694 * those provided in that allocation request.
696 void usb_buffer_free (
697 struct usb_device
*dev
,
703 if (!dev
|| !dev
->bus
|| !dev
->bus
->op
|| !dev
->bus
->op
->buffer_free
)
707 dev
->bus
->op
->buffer_free (dev
->bus
, size
, addr
, dma
);
711 * usb_buffer_map - create DMA mapping(s) for an urb
712 * @urb: urb whose transfer_buffer/setup_packet will be mapped
714 * Return value is either null (indicating no buffer could be mapped), or
715 * the parameter. URB_NO_TRANSFER_DMA_MAP and URB_NO_SETUP_DMA_MAP are
716 * added to urb->transfer_flags if the operation succeeds. If the device
717 * is connected to this system through a non-DMA controller, this operation
720 * This call would normally be used for an urb which is reused, perhaps
721 * as the target of a large periodic transfer, with usb_buffer_dmasync()
722 * calls to synchronize memory and dma state.
724 * Reverse the effect of this call with usb_buffer_unmap().
727 struct urb
*usb_buffer_map (struct urb
*urb
)
730 struct device
*controller
;
734 || !(bus
= urb
->dev
->bus
)
735 || !(controller
= bus
->controller
))
738 if (controller
->dma_mask
) {
739 urb
->transfer_dma
= dma_map_single (controller
,
740 urb
->transfer_buffer
, urb
->transfer_buffer_length
,
741 usb_pipein (urb
->pipe
)
742 ? DMA_FROM_DEVICE
: DMA_TO_DEVICE
);
743 if (usb_pipecontrol (urb
->pipe
))
744 urb
->setup_dma
= dma_map_single (controller
,
746 sizeof (struct usb_ctrlrequest
),
748 // FIXME generic api broken like pci, can't report errors
749 // if (urb->transfer_dma == DMA_ADDR_INVALID) return 0;
751 urb
->transfer_dma
= ~0;
752 urb
->transfer_flags
|= (URB_NO_TRANSFER_DMA_MAP
753 | URB_NO_SETUP_DMA_MAP
);
758 /* XXX DISABLED, no users currently. If you wish to re-enable this
759 * XXX please determine whether the sync is to transfer ownership of
760 * XXX the buffer from device to cpu or vice verse, and thusly use the
761 * XXX appropriate _for_{cpu,device}() method. -DaveM
766 * usb_buffer_dmasync - synchronize DMA and CPU view of buffer(s)
767 * @urb: urb whose transfer_buffer/setup_packet will be synchronized
769 void usb_buffer_dmasync (struct urb
*urb
)
772 struct device
*controller
;
775 || !(urb
->transfer_flags
& URB_NO_TRANSFER_DMA_MAP
)
777 || !(bus
= urb
->dev
->bus
)
778 || !(controller
= bus
->controller
))
781 if (controller
->dma_mask
) {
782 dma_sync_single (controller
,
783 urb
->transfer_dma
, urb
->transfer_buffer_length
,
784 usb_pipein (urb
->pipe
)
785 ? DMA_FROM_DEVICE
: DMA_TO_DEVICE
);
786 if (usb_pipecontrol (urb
->pipe
))
787 dma_sync_single (controller
,
789 sizeof (struct usb_ctrlrequest
),
796 * usb_buffer_unmap - free DMA mapping(s) for an urb
797 * @urb: urb whose transfer_buffer will be unmapped
799 * Reverses the effect of usb_buffer_map().
802 void usb_buffer_unmap (struct urb
*urb
)
805 struct device
*controller
;
808 || !(urb
->transfer_flags
& URB_NO_TRANSFER_DMA_MAP
)
810 || !(bus
= urb
->dev
->bus
)
811 || !(controller
= bus
->controller
))
814 if (controller
->dma_mask
) {
815 dma_unmap_single (controller
,
816 urb
->transfer_dma
, urb
->transfer_buffer_length
,
817 usb_pipein (urb
->pipe
)
818 ? DMA_FROM_DEVICE
: DMA_TO_DEVICE
);
819 if (usb_pipecontrol (urb
->pipe
))
820 dma_unmap_single (controller
,
822 sizeof (struct usb_ctrlrequest
),
825 urb
->transfer_flags
&= ~(URB_NO_TRANSFER_DMA_MAP
826 | URB_NO_SETUP_DMA_MAP
);
831 * usb_buffer_map_sg - create scatterlist DMA mapping(s) for an endpoint
832 * @dev: device to which the scatterlist will be mapped
833 * @pipe: endpoint defining the mapping direction
834 * @sg: the scatterlist to map
835 * @nents: the number of entries in the scatterlist
837 * Return value is either < 0 (indicating no buffers could be mapped), or
838 * the number of DMA mapping array entries in the scatterlist.
840 * The caller is responsible for placing the resulting DMA addresses from
841 * the scatterlist into URB transfer buffer pointers, and for setting the
842 * URB_NO_TRANSFER_DMA_MAP transfer flag in each of those URBs.
844 * Top I/O rates come from queuing URBs, instead of waiting for each one
845 * to complete before starting the next I/O. This is particularly easy
846 * to do with scatterlists. Just allocate and submit one URB for each DMA
847 * mapping entry returned, stopping on the first error or when all succeed.
848 * Better yet, use the usb_sg_*() calls, which do that (and more) for you.
850 * This call would normally be used when translating scatterlist requests,
851 * rather than usb_buffer_map(), since on some hardware (with IOMMUs) it
852 * may be able to coalesce mappings for improved I/O efficiency.
854 * Reverse the effect of this call with usb_buffer_unmap_sg().
856 int usb_buffer_map_sg(const struct usb_device
*dev
, unsigned pipe
,
857 struct scatterlist
*sg
, int nents
)
860 struct device
*controller
;
863 || usb_pipecontrol (pipe
)
865 || !(controller
= bus
->controller
)
866 || !controller
->dma_mask
)
869 // FIXME generic api broken like pci, can't report errors
870 return dma_map_sg (controller
, sg
, nents
,
871 usb_pipein (pipe
) ? DMA_FROM_DEVICE
: DMA_TO_DEVICE
);
874 /* XXX DISABLED, no users currently. If you wish to re-enable this
875 * XXX please determine whether the sync is to transfer ownership of
876 * XXX the buffer from device to cpu or vice verse, and thusly use the
877 * XXX appropriate _for_{cpu,device}() method. -DaveM
882 * usb_buffer_dmasync_sg - synchronize DMA and CPU view of scatterlist buffer(s)
883 * @dev: device to which the scatterlist will be mapped
884 * @pipe: endpoint defining the mapping direction
885 * @sg: the scatterlist to synchronize
886 * @n_hw_ents: the positive return value from usb_buffer_map_sg
888 * Use this when you are re-using a scatterlist's data buffers for
889 * another USB request.
891 void usb_buffer_dmasync_sg(const struct usb_device
*dev
, unsigned pipe
,
892 struct scatterlist
*sg
, int n_hw_ents
)
895 struct device
*controller
;
899 || !(controller
= bus
->controller
)
900 || !controller
->dma_mask
)
903 dma_sync_sg (controller
, sg
, n_hw_ents
,
904 usb_pipein (pipe
) ? DMA_FROM_DEVICE
: DMA_TO_DEVICE
);
909 * usb_buffer_unmap_sg - free DMA mapping(s) for a scatterlist
910 * @dev: device to which the scatterlist will be mapped
911 * @pipe: endpoint defining the mapping direction
912 * @sg: the scatterlist to unmap
913 * @n_hw_ents: the positive return value from usb_buffer_map_sg
915 * Reverses the effect of usb_buffer_map_sg().
917 void usb_buffer_unmap_sg(const struct usb_device
*dev
, unsigned pipe
,
918 struct scatterlist
*sg
, int n_hw_ents
)
921 struct device
*controller
;
925 || !(controller
= bus
->controller
)
926 || !controller
->dma_mask
)
929 dma_unmap_sg (controller
, sg
, n_hw_ents
,
930 usb_pipein (pipe
) ? DMA_FROM_DEVICE
: DMA_TO_DEVICE
);
933 /* format to disable USB on kernel command line is: nousb */
934 __module_param_call("", nousb
, param_set_bool
, param_get_bool
, &nousb
, 0444);
937 * for external read access to <nousb>
939 int usb_disabled(void)
947 static int __init
usb_init(void)
951 pr_info ("%s: USB support disabled\n", usbcore_name
);
955 retval
= bus_register(&usb_bus_type
);
958 retval
= usb_host_init();
960 goto host_init_failed
;
961 retval
= usb_major_init();
963 goto major_init_failed
;
964 retval
= usb_register(&usbfs_driver
);
966 goto driver_register_failed
;
967 retval
= usbdev_init();
969 goto usbdevice_init_failed
;
970 retval
= usbfs_init();
973 retval
= usb_hub_init();
975 goto hub_init_failed
;
976 retval
= usb_register_device_driver(&usb_generic_driver
, THIS_MODULE
);
985 usbdevice_init_failed
:
986 usb_deregister(&usbfs_driver
);
987 driver_register_failed
:
992 bus_unregister(&usb_bus_type
);
1000 static void __exit
usb_exit(void)
1002 /* This will matter if shutdown/reboot does exitcalls. */
1006 usb_deregister_device_driver(&usb_generic_driver
);
1007 usb_major_cleanup();
1009 usb_deregister(&usbfs_driver
);
1013 bus_unregister(&usb_bus_type
);
1016 subsys_initcall(usb_init
);
1017 module_exit(usb_exit
);
1020 * USB may be built into the kernel or be built as modules.
1021 * These symbols are exported for device (or host controller)
1022 * driver modules to use.
1025 EXPORT_SYMBOL(usb_disabled
);
1027 EXPORT_SYMBOL_GPL(usb_get_intf
);
1028 EXPORT_SYMBOL_GPL(usb_put_intf
);
1030 EXPORT_SYMBOL(usb_put_dev
);
1031 EXPORT_SYMBOL(usb_get_dev
);
1032 EXPORT_SYMBOL(usb_hub_tt_clear_buffer
);
1034 EXPORT_SYMBOL(usb_lock_device_for_reset
);
1036 EXPORT_SYMBOL(usb_find_interface
);
1037 EXPORT_SYMBOL(usb_ifnum_to_if
);
1038 EXPORT_SYMBOL(usb_altnum_to_altsetting
);
1040 EXPORT_SYMBOL(__usb_get_extra_descriptor
);
1042 EXPORT_SYMBOL(usb_find_device
);
1043 EXPORT_SYMBOL(usb_get_current_frame_number
);
1045 EXPORT_SYMBOL_GPL(usb_endpoint_dir_in
);
1046 EXPORT_SYMBOL_GPL(usb_endpoint_dir_out
);
1047 EXPORT_SYMBOL_GPL(usb_endpoint_xfer_bulk
);
1048 EXPORT_SYMBOL_GPL(usb_endpoint_xfer_int
);
1049 EXPORT_SYMBOL_GPL(usb_endpoint_xfer_isoc
);
1050 EXPORT_SYMBOL_GPL(usb_endpoint_is_bulk_in
);
1051 EXPORT_SYMBOL_GPL(usb_endpoint_is_bulk_out
);
1052 EXPORT_SYMBOL_GPL(usb_endpoint_is_int_in
);
1053 EXPORT_SYMBOL_GPL(usb_endpoint_is_int_out
);
1054 EXPORT_SYMBOL_GPL(usb_endpoint_is_isoc_in
);
1055 EXPORT_SYMBOL_GPL(usb_endpoint_is_isoc_out
);
1057 EXPORT_SYMBOL (usb_buffer_alloc
);
1058 EXPORT_SYMBOL (usb_buffer_free
);
1061 EXPORT_SYMBOL (usb_buffer_map
);
1062 EXPORT_SYMBOL (usb_buffer_dmasync
);
1063 EXPORT_SYMBOL (usb_buffer_unmap
);
1066 EXPORT_SYMBOL (usb_buffer_map_sg
);
1068 EXPORT_SYMBOL (usb_buffer_dmasync_sg
);
1070 EXPORT_SYMBOL (usb_buffer_unmap_sg
);
1072 MODULE_LICENSE("GPL");