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(struct usb_device
*dev
, unsigned ifnum
)
72 struct usb_host_config
*config
= dev
->actconfig
;
77 for (i
= 0; i
< config
->desc
.bNumInterfaces
; i
++)
78 if (config
->interface
[i
]->altsetting
[0]
79 .desc
.bInterfaceNumber
== ifnum
)
80 return config
->interface
[i
];
86 * usb_altnum_to_altsetting - get the altsetting structure with a given
87 * alternate setting number.
88 * @intf: the interface containing the altsetting in question
89 * @altnum: the desired alternate setting number
91 * This searches the altsetting array of the specified interface for
92 * an entry with the correct bAlternateSetting value and returns a pointer
93 * to that entry, or null.
95 * Note that altsettings need not be stored sequentially by number, so
96 * it would be incorrect to assume that the first altsetting entry in
97 * the array corresponds to altsetting zero. This routine helps device
98 * drivers avoid such mistakes.
100 * Don't call this function unless you are bound to the intf interface
101 * or you have locked the device!
103 struct usb_host_interface
*usb_altnum_to_altsetting(struct usb_interface
*intf
,
108 for (i
= 0; i
< intf
->num_altsetting
; i
++) {
109 if (intf
->altsetting
[i
].desc
.bAlternateSetting
== altnum
)
110 return &intf
->altsetting
[i
];
116 * usb_driver_claim_interface - bind a driver to an interface
117 * @driver: the driver to be bound
118 * @iface: the interface to which it will be bound; must be in the
119 * usb device's active configuration
120 * @priv: driver data associated with that interface
122 * This is used by usb device drivers that need to claim more than one
123 * interface on a device when probing (audio and acm are current examples).
124 * No device driver should directly modify internal usb_interface or
125 * usb_device structure members.
127 * Few drivers should need to use this routine, since the most natural
128 * way to bind to an interface is to return the private data from
129 * the driver's probe() method.
131 * Callers must own the device lock and the driver model's usb_bus_type.subsys
132 * writelock. So driver probe() entries don't need extra locking,
133 * but other call contexts may need to explicitly claim those locks.
135 int usb_driver_claim_interface(struct usb_driver
*driver
,
136 struct usb_interface
*iface
, void* priv
)
138 struct device
*dev
= &iface
->dev
;
143 dev
->driver
= &driver
->driver
;
144 usb_set_intfdata(iface
, priv
);
145 iface
->condition
= USB_INTERFACE_BOUND
;
148 /* if interface was already added, bind now; else let
149 * the future device_add() bind it, bypassing probe()
151 if (device_is_registered(dev
))
152 device_bind_driver(dev
);
158 * usb_driver_release_interface - unbind a driver from an interface
159 * @driver: the driver to be unbound
160 * @iface: the interface from which it will be unbound
162 * This can be used by drivers to release an interface without waiting
163 * for their disconnect() methods to be called. In typical cases this
164 * also causes the driver disconnect() method to be called.
166 * This call is synchronous, and may not be used in an interrupt context.
167 * Callers must own the device lock and the driver model's usb_bus_type.subsys
168 * writelock. So driver disconnect() entries don't need extra locking,
169 * but other call contexts may need to explicitly claim those locks.
171 void usb_driver_release_interface(struct usb_driver
*driver
,
172 struct usb_interface
*iface
)
174 struct device
*dev
= &iface
->dev
;
176 /* this should never happen, don't release something that's not ours */
177 if (!dev
->driver
|| dev
->driver
!= &driver
->driver
)
180 /* don't release from within disconnect() */
181 if (iface
->condition
!= USB_INTERFACE_BOUND
)
184 /* don't release if the interface hasn't been added yet */
185 if (device_is_registered(dev
)) {
186 iface
->condition
= USB_INTERFACE_UNBINDING
;
187 device_release_driver(dev
);
191 usb_set_intfdata(iface
, NULL
);
192 iface
->condition
= USB_INTERFACE_UNBOUND
;
193 mark_quiesced(iface
);
196 struct find_interface_arg
{
198 struct usb_interface
*interface
;
201 static int __find_interface(struct device
* dev
, void * data
)
203 struct find_interface_arg
*arg
= data
;
204 struct usb_interface
*intf
;
206 /* can't look at usb devices, only interfaces */
207 if (dev
->driver
== &usb_generic_driver
)
210 intf
= to_usb_interface(dev
);
211 if (intf
->minor
!= -1 && intf
->minor
== arg
->minor
) {
212 arg
->interface
= intf
;
219 * usb_find_interface - find usb_interface pointer for driver and device
220 * @drv: the driver whose current configuration is considered
221 * @minor: the minor number of the desired device
223 * This walks the driver device list and returns a pointer to the interface
224 * with the matching minor. Note, this only works for devices that share the
227 struct usb_interface
*usb_find_interface(struct usb_driver
*drv
, int minor
)
229 struct find_interface_arg argb
;
232 argb
.interface
= NULL
;
233 driver_for_each_device(&drv
->driver
, NULL
, &argb
, __find_interface
);
234 return argb
.interface
;
237 #ifdef CONFIG_HOTPLUG
240 * This sends an uevent to userspace, typically helping to load driver
241 * or other modules, configure the device, and more. Drivers can provide
242 * a MODULE_DEVICE_TABLE to help with module loading subtasks.
244 * We're called either from khubd (the typical case) or from root hub
245 * (init, kapmd, modprobe, rmmod, etc), but the agents need to handle
246 * delays in event delivery. Use sysfs (and DEVPATH) to make sure the
247 * device (and this configuration!) are still present.
249 static int usb_uevent(struct device
*dev
, char **envp
, int num_envp
,
250 char *buffer
, int buffer_size
)
252 struct usb_interface
*intf
;
253 struct usb_device
*usb_dev
;
254 struct usb_host_interface
*alt
;
261 /* driver is often null here; dev_dbg() would oops */
262 pr_debug ("usb %s: uevent\n", dev
->bus_id
);
264 /* Must check driver_data here, as on remove driver is always NULL */
265 if ((dev
->driver
== &usb_generic_driver
) ||
266 (dev
->driver_data
== &usb_generic_driver_data
))
269 intf
= to_usb_interface(dev
);
270 usb_dev
= interface_to_usbdev (intf
);
271 alt
= intf
->cur_altsetting
;
273 if (usb_dev
->devnum
< 0) {
274 pr_debug ("usb %s: already deleted?\n", dev
->bus_id
);
278 pr_debug ("usb %s: bus removed?\n", dev
->bus_id
);
282 #ifdef CONFIG_USB_DEVICEFS
283 /* If this is available, userspace programs can directly read
284 * all the device descriptors we don't tell them about. Or
285 * even act as usermode drivers.
287 * FIXME reduce hardwired intelligence here
289 if (add_uevent_var(envp
, num_envp
, &i
,
290 buffer
, buffer_size
, &length
,
291 "DEVICE=/proc/bus/usb/%03d/%03d",
292 usb_dev
->bus
->busnum
, usb_dev
->devnum
))
296 /* per-device configurations are common */
297 if (add_uevent_var(envp
, num_envp
, &i
,
298 buffer
, buffer_size
, &length
,
300 le16_to_cpu(usb_dev
->descriptor
.idVendor
),
301 le16_to_cpu(usb_dev
->descriptor
.idProduct
),
302 le16_to_cpu(usb_dev
->descriptor
.bcdDevice
)))
305 /* class-based driver binding models */
306 if (add_uevent_var(envp
, num_envp
, &i
,
307 buffer
, buffer_size
, &length
,
309 usb_dev
->descriptor
.bDeviceClass
,
310 usb_dev
->descriptor
.bDeviceSubClass
,
311 usb_dev
->descriptor
.bDeviceProtocol
))
314 if (add_uevent_var(envp
, num_envp
, &i
,
315 buffer
, buffer_size
, &length
,
316 "INTERFACE=%d/%d/%d",
317 alt
->desc
.bInterfaceClass
,
318 alt
->desc
.bInterfaceSubClass
,
319 alt
->desc
.bInterfaceProtocol
))
322 if (add_uevent_var(envp
, num_envp
, &i
,
323 buffer
, buffer_size
, &length
,
324 "MODALIAS=usb:v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02Xic%02Xisc%02Xip%02X",
325 le16_to_cpu(usb_dev
->descriptor
.idVendor
),
326 le16_to_cpu(usb_dev
->descriptor
.idProduct
),
327 le16_to_cpu(usb_dev
->descriptor
.bcdDevice
),
328 usb_dev
->descriptor
.bDeviceClass
,
329 usb_dev
->descriptor
.bDeviceSubClass
,
330 usb_dev
->descriptor
.bDeviceProtocol
,
331 alt
->desc
.bInterfaceClass
,
332 alt
->desc
.bInterfaceSubClass
,
333 alt
->desc
.bInterfaceProtocol
))
343 static int usb_uevent(struct device
*dev
, char **envp
,
344 int num_envp
, char *buffer
, int buffer_size
)
349 #endif /* CONFIG_HOTPLUG */
352 * usb_release_dev - free a usb device structure when all users of it are finished.
353 * @dev: device that's been disconnected
355 * Will be called only by the device core when all users of this usb device are
358 static void usb_release_dev(struct device
*dev
)
360 struct usb_device
*udev
;
362 udev
= to_usb_device(dev
);
364 usb_destroy_configuration(udev
);
365 usb_bus_put(udev
->bus
);
366 kfree(udev
->product
);
367 kfree(udev
->manufacturer
);
373 * usb_alloc_dev - usb device constructor (usbcore-internal)
374 * @parent: hub to which device is connected; null to allocate a root hub
375 * @bus: bus used to access the device
376 * @port1: one-based index of port; ignored for root hubs
377 * Context: !in_interrupt ()
379 * Only hub drivers (including virtual root hub drivers for host
380 * controllers) should ever call this.
382 * This call may not be used in a non-sleeping context.
385 usb_alloc_dev(struct usb_device
*parent
, struct usb_bus
*bus
, unsigned port1
)
387 struct usb_device
*dev
;
389 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
393 bus
= usb_bus_get(bus
);
399 device_initialize(&dev
->dev
);
400 dev
->dev
.bus
= &usb_bus_type
;
401 dev
->dev
.dma_mask
= bus
->controller
->dma_mask
;
402 dev
->dev
.driver_data
= &usb_generic_driver_data
;
403 dev
->dev
.driver
= &usb_generic_driver
;
404 dev
->dev
.release
= usb_release_dev
;
405 dev
->state
= USB_STATE_ATTACHED
;
407 INIT_LIST_HEAD(&dev
->ep0
.urb_list
);
408 dev
->ep0
.desc
.bLength
= USB_DT_ENDPOINT_SIZE
;
409 dev
->ep0
.desc
.bDescriptorType
= USB_DT_ENDPOINT
;
410 /* ep0 maxpacket comes later, from device descriptor */
411 dev
->ep_in
[0] = dev
->ep_out
[0] = &dev
->ep0
;
413 /* Save readable and stable topology id, distinguishing devices
414 * by location for diagnostics, tools, driver model, etc. The
415 * string is a path along hub ports, from the root. Each device's
416 * dev->devpath will be stable until USB is re-cabled, and hubs
417 * are often labeled with these port numbers. The bus_id isn't
418 * as stable: bus->busnum changes easily from modprobe order,
419 * cardbus or pci hotplugging, and so on.
421 if (unlikely (!parent
)) {
422 dev
->devpath
[0] = '0';
424 dev
->dev
.parent
= bus
->controller
;
425 sprintf (&dev
->dev
.bus_id
[0], "usb%d", bus
->busnum
);
427 /* match any labeling on the hubs; it's one-based */
428 if (parent
->devpath
[0] == '0')
429 snprintf (dev
->devpath
, sizeof dev
->devpath
,
432 snprintf (dev
->devpath
, sizeof dev
->devpath
,
433 "%s.%d", parent
->devpath
, port1
);
435 dev
->dev
.parent
= &parent
->dev
;
436 sprintf (&dev
->dev
.bus_id
[0], "%d-%s",
437 bus
->busnum
, dev
->devpath
);
439 /* hub driver sets up TT records */
442 dev
->portnum
= port1
;
444 dev
->parent
= parent
;
445 INIT_LIST_HEAD(&dev
->filelist
);
451 * usb_get_dev - increments the reference count of the usb device structure
452 * @dev: the device being referenced
454 * Each live reference to a device should be refcounted.
456 * Drivers for USB interfaces should normally record such references in
457 * their probe() methods, when they bind to an interface, and release
458 * them by calling usb_put_dev(), in their disconnect() methods.
460 * A pointer to the device with the incremented reference counter is returned.
462 struct usb_device
*usb_get_dev(struct usb_device
*dev
)
465 get_device(&dev
->dev
);
470 * usb_put_dev - release a use of the usb device structure
471 * @dev: device that's been disconnected
473 * Must be called when a user of a device is finished with it. When the last
474 * user of the device calls this function, the memory of the device is freed.
476 void usb_put_dev(struct usb_device
*dev
)
479 put_device(&dev
->dev
);
483 * usb_get_intf - increments the reference count of the usb interface structure
484 * @intf: the interface being referenced
486 * Each live reference to a interface must be refcounted.
488 * Drivers for USB interfaces should normally record such references in
489 * their probe() methods, when they bind to an interface, and release
490 * them by calling usb_put_intf(), in their disconnect() methods.
492 * A pointer to the interface with the incremented reference counter is
495 struct usb_interface
*usb_get_intf(struct usb_interface
*intf
)
498 get_device(&intf
->dev
);
503 * usb_put_intf - release a use of the usb interface structure
504 * @intf: interface that's been decremented
506 * Must be called when a user of an interface is finished with it. When the
507 * last user of the interface calls this function, the memory of the interface
510 void usb_put_intf(struct usb_interface
*intf
)
513 put_device(&intf
->dev
);
517 /* USB device locking
519 * USB devices and interfaces are locked using the semaphore in their
520 * embedded struct device. The hub driver guarantees that whenever a
521 * device is connected or disconnected, drivers are called with the
522 * USB device locked as well as their particular interface.
524 * Complications arise when several devices are to be locked at the same
525 * time. Only hub-aware drivers that are part of usbcore ever have to
526 * do this; nobody else needs to worry about it. The rule for locking
529 * When locking both a device and its parent, always lock the
534 * usb_lock_device_for_reset - cautiously acquire the lock for a
535 * usb device structure
536 * @udev: device that's being locked
537 * @iface: interface bound to the driver making the request (optional)
539 * Attempts to acquire the device lock, but fails if the device is
540 * NOTATTACHED or SUSPENDED, or if iface is specified and the interface
541 * is neither BINDING nor BOUND. Rather than sleeping to wait for the
542 * lock, the routine polls repeatedly. This is to prevent deadlock with
543 * disconnect; in some drivers (such as usb-storage) the disconnect()
544 * or suspend() method will block waiting for a device reset to complete.
546 * Returns a negative error code for failure, otherwise 1 or 0 to indicate
547 * that the device will or will not have to be unlocked. (0 can be
548 * returned when an interface is given and is BINDING, because in that
549 * case the driver already owns the device lock.)
551 int usb_lock_device_for_reset(struct usb_device
*udev
,
552 struct usb_interface
*iface
)
554 unsigned long jiffies_expire
= jiffies
+ HZ
;
556 if (udev
->state
== USB_STATE_NOTATTACHED
)
558 if (udev
->state
== USB_STATE_SUSPENDED
)
559 return -EHOSTUNREACH
;
561 switch (iface
->condition
) {
562 case USB_INTERFACE_BINDING
:
564 case USB_INTERFACE_BOUND
:
571 while (usb_trylock_device(udev
) != 0) {
573 /* If we can't acquire the lock after waiting one second,
574 * we're probably deadlocked */
575 if (time_after(jiffies
, jiffies_expire
))
579 if (udev
->state
== USB_STATE_NOTATTACHED
)
581 if (udev
->state
== USB_STATE_SUSPENDED
)
582 return -EHOSTUNREACH
;
583 if (iface
&& iface
->condition
!= USB_INTERFACE_BOUND
)
590 static struct usb_device
*match_device(struct usb_device
*dev
,
591 u16 vendor_id
, u16 product_id
)
593 struct usb_device
*ret_dev
= NULL
;
596 dev_dbg(&dev
->dev
, "check for vendor %04x, product %04x ...\n",
597 le16_to_cpu(dev
->descriptor
.idVendor
),
598 le16_to_cpu(dev
->descriptor
.idProduct
));
600 /* see if this device matches */
601 if ((vendor_id
== le16_to_cpu(dev
->descriptor
.idVendor
)) &&
602 (product_id
== le16_to_cpu(dev
->descriptor
.idProduct
))) {
603 dev_dbg (&dev
->dev
, "matched this device!\n");
604 ret_dev
= usb_get_dev(dev
);
608 /* look through all of the children of this device */
609 for (child
= 0; child
< dev
->maxchild
; ++child
) {
610 if (dev
->children
[child
]) {
611 usb_lock_device(dev
->children
[child
]);
612 ret_dev
= match_device(dev
->children
[child
],
613 vendor_id
, product_id
);
614 usb_unlock_device(dev
->children
[child
]);
624 * usb_find_device - find a specific usb device in the system
625 * @vendor_id: the vendor id of the device to find
626 * @product_id: the product id of the device to find
628 * Returns a pointer to a struct usb_device if such a specified usb
629 * device is present in the system currently. The usage count of the
630 * device will be incremented if a device is found. Make sure to call
631 * usb_put_dev() when the caller is finished with the device.
633 * If a device with the specified vendor and product id is not found,
636 struct usb_device
*usb_find_device(u16 vendor_id
, u16 product_id
)
638 struct list_head
*buslist
;
640 struct usb_device
*dev
= NULL
;
642 mutex_lock(&usb_bus_list_lock
);
643 for (buslist
= usb_bus_list
.next
;
644 buslist
!= &usb_bus_list
;
645 buslist
= buslist
->next
) {
646 bus
= container_of(buslist
, struct usb_bus
, bus_list
);
649 usb_lock_device(bus
->root_hub
);
650 dev
= match_device(bus
->root_hub
, vendor_id
, product_id
);
651 usb_unlock_device(bus
->root_hub
);
656 mutex_unlock(&usb_bus_list_lock
);
661 * usb_get_current_frame_number - return current bus frame number
662 * @dev: the device whose bus is being queried
664 * Returns the current frame number for the USB host controller
665 * used with the given USB device. This can be used when scheduling
666 * isochronous requests.
668 * Note that different kinds of host controller have different
669 * "scheduling horizons". While one type might support scheduling only
670 * 32 frames into the future, others could support scheduling up to
671 * 1024 frames into the future.
673 int usb_get_current_frame_number(struct usb_device
*dev
)
675 return dev
->bus
->op
->get_frame_number (dev
);
678 /*-------------------------------------------------------------------*/
680 * __usb_get_extra_descriptor() finds a descriptor of specific type in the
681 * extra field of the interface and endpoint descriptor structs.
684 int __usb_get_extra_descriptor(char *buffer
, unsigned size
,
685 unsigned char type
, void **ptr
)
687 struct usb_descriptor_header
*header
;
689 while (size
>= sizeof(struct usb_descriptor_header
)) {
690 header
= (struct usb_descriptor_header
*)buffer
;
692 if (header
->bLength
< 2) {
694 "%s: bogus descriptor, type %d length %d\n",
696 header
->bDescriptorType
,
701 if (header
->bDescriptorType
== type
) {
706 buffer
+= header
->bLength
;
707 size
-= header
->bLength
;
713 * usb_buffer_alloc - allocate dma-consistent buffer for URB_NO_xxx_DMA_MAP
714 * @dev: device the buffer will be used with
715 * @size: requested buffer size
716 * @mem_flags: affect whether allocation may block
717 * @dma: used to return DMA address of buffer
719 * Return value is either null (indicating no buffer could be allocated), or
720 * the cpu-space pointer to a buffer that may be used to perform DMA to the
721 * specified device. Such cpu-space buffers are returned along with the DMA
722 * address (through the pointer provided).
724 * These buffers are used with URB_NO_xxx_DMA_MAP set in urb->transfer_flags
725 * to avoid behaviors like using "DMA bounce buffers", or tying down I/O
726 * mapping hardware for long idle periods. The implementation varies between
727 * platforms, depending on details of how DMA will work to this device.
728 * Using these buffers also helps prevent cacheline sharing problems on
729 * architectures where CPU caches are not DMA-coherent.
731 * When the buffer is no longer used, free it with usb_buffer_free().
733 void *usb_buffer_alloc (
734 struct usb_device
*dev
,
740 if (!dev
|| !dev
->bus
|| !dev
->bus
->op
|| !dev
->bus
->op
->buffer_alloc
)
742 return dev
->bus
->op
->buffer_alloc (dev
->bus
, size
, mem_flags
, dma
);
746 * usb_buffer_free - free memory allocated with usb_buffer_alloc()
747 * @dev: device the buffer was used with
748 * @size: requested buffer size
749 * @addr: CPU address of buffer
750 * @dma: DMA address of buffer
752 * This reclaims an I/O buffer, letting it be reused. The memory must have
753 * been allocated using usb_buffer_alloc(), and the parameters must match
754 * those provided in that allocation request.
756 void usb_buffer_free (
757 struct usb_device
*dev
,
763 if (!dev
|| !dev
->bus
|| !dev
->bus
->op
|| !dev
->bus
->op
->buffer_free
)
765 dev
->bus
->op
->buffer_free (dev
->bus
, size
, addr
, dma
);
769 * usb_buffer_map - create DMA mapping(s) for an urb
770 * @urb: urb whose transfer_buffer/setup_packet will be mapped
772 * Return value is either null (indicating no buffer could be mapped), or
773 * the parameter. URB_NO_TRANSFER_DMA_MAP and URB_NO_SETUP_DMA_MAP are
774 * added to urb->transfer_flags if the operation succeeds. If the device
775 * is connected to this system through a non-DMA controller, this operation
778 * This call would normally be used for an urb which is reused, perhaps
779 * as the target of a large periodic transfer, with usb_buffer_dmasync()
780 * calls to synchronize memory and dma state.
782 * Reverse the effect of this call with usb_buffer_unmap().
785 struct urb
*usb_buffer_map (struct urb
*urb
)
788 struct device
*controller
;
792 || !(bus
= urb
->dev
->bus
)
793 || !(controller
= bus
->controller
))
796 if (controller
->dma_mask
) {
797 urb
->transfer_dma
= dma_map_single (controller
,
798 urb
->transfer_buffer
, urb
->transfer_buffer_length
,
799 usb_pipein (urb
->pipe
)
800 ? DMA_FROM_DEVICE
: DMA_TO_DEVICE
);
801 if (usb_pipecontrol (urb
->pipe
))
802 urb
->setup_dma
= dma_map_single (controller
,
804 sizeof (struct usb_ctrlrequest
),
806 // FIXME generic api broken like pci, can't report errors
807 // if (urb->transfer_dma == DMA_ADDR_INVALID) return 0;
809 urb
->transfer_dma
= ~0;
810 urb
->transfer_flags
|= (URB_NO_TRANSFER_DMA_MAP
811 | URB_NO_SETUP_DMA_MAP
);
816 /* XXX DISABLED, no users currently. If you wish to re-enable this
817 * XXX please determine whether the sync is to transfer ownership of
818 * XXX the buffer from device to cpu or vice verse, and thusly use the
819 * XXX appropriate _for_{cpu,device}() method. -DaveM
824 * usb_buffer_dmasync - synchronize DMA and CPU view of buffer(s)
825 * @urb: urb whose transfer_buffer/setup_packet will be synchronized
827 void usb_buffer_dmasync (struct urb
*urb
)
830 struct device
*controller
;
833 || !(urb
->transfer_flags
& URB_NO_TRANSFER_DMA_MAP
)
835 || !(bus
= urb
->dev
->bus
)
836 || !(controller
= bus
->controller
))
839 if (controller
->dma_mask
) {
840 dma_sync_single (controller
,
841 urb
->transfer_dma
, urb
->transfer_buffer_length
,
842 usb_pipein (urb
->pipe
)
843 ? DMA_FROM_DEVICE
: DMA_TO_DEVICE
);
844 if (usb_pipecontrol (urb
->pipe
))
845 dma_sync_single (controller
,
847 sizeof (struct usb_ctrlrequest
),
854 * usb_buffer_unmap - free DMA mapping(s) for an urb
855 * @urb: urb whose transfer_buffer will be unmapped
857 * Reverses the effect of usb_buffer_map().
860 void usb_buffer_unmap (struct urb
*urb
)
863 struct device
*controller
;
866 || !(urb
->transfer_flags
& URB_NO_TRANSFER_DMA_MAP
)
868 || !(bus
= urb
->dev
->bus
)
869 || !(controller
= bus
->controller
))
872 if (controller
->dma_mask
) {
873 dma_unmap_single (controller
,
874 urb
->transfer_dma
, urb
->transfer_buffer_length
,
875 usb_pipein (urb
->pipe
)
876 ? DMA_FROM_DEVICE
: DMA_TO_DEVICE
);
877 if (usb_pipecontrol (urb
->pipe
))
878 dma_unmap_single (controller
,
880 sizeof (struct usb_ctrlrequest
),
883 urb
->transfer_flags
&= ~(URB_NO_TRANSFER_DMA_MAP
884 | URB_NO_SETUP_DMA_MAP
);
889 * usb_buffer_map_sg - create scatterlist DMA mapping(s) for an endpoint
890 * @dev: device to which the scatterlist will be mapped
891 * @pipe: endpoint defining the mapping direction
892 * @sg: the scatterlist to map
893 * @nents: the number of entries in the scatterlist
895 * Return value is either < 0 (indicating no buffers could be mapped), or
896 * the number of DMA mapping array entries in the scatterlist.
898 * The caller is responsible for placing the resulting DMA addresses from
899 * the scatterlist into URB transfer buffer pointers, and for setting the
900 * URB_NO_TRANSFER_DMA_MAP transfer flag in each of those URBs.
902 * Top I/O rates come from queuing URBs, instead of waiting for each one
903 * to complete before starting the next I/O. This is particularly easy
904 * to do with scatterlists. Just allocate and submit one URB for each DMA
905 * mapping entry returned, stopping on the first error or when all succeed.
906 * Better yet, use the usb_sg_*() calls, which do that (and more) for you.
908 * This call would normally be used when translating scatterlist requests,
909 * rather than usb_buffer_map(), since on some hardware (with IOMMUs) it
910 * may be able to coalesce mappings for improved I/O efficiency.
912 * Reverse the effect of this call with usb_buffer_unmap_sg().
914 int usb_buffer_map_sg (struct usb_device
*dev
, unsigned pipe
,
915 struct scatterlist
*sg
, int nents
)
918 struct device
*controller
;
921 || usb_pipecontrol (pipe
)
923 || !(controller
= bus
->controller
)
924 || !controller
->dma_mask
)
927 // FIXME generic api broken like pci, can't report errors
928 return dma_map_sg (controller
, sg
, nents
,
929 usb_pipein (pipe
) ? DMA_FROM_DEVICE
: DMA_TO_DEVICE
);
932 /* XXX DISABLED, no users currently. If you wish to re-enable this
933 * XXX please determine whether the sync is to transfer ownership of
934 * XXX the buffer from device to cpu or vice verse, and thusly use the
935 * XXX appropriate _for_{cpu,device}() method. -DaveM
940 * usb_buffer_dmasync_sg - synchronize DMA and CPU view of scatterlist buffer(s)
941 * @dev: device to which the scatterlist will be mapped
942 * @pipe: endpoint defining the mapping direction
943 * @sg: the scatterlist to synchronize
944 * @n_hw_ents: the positive return value from usb_buffer_map_sg
946 * Use this when you are re-using a scatterlist's data buffers for
947 * another USB request.
949 void usb_buffer_dmasync_sg (struct usb_device
*dev
, unsigned pipe
,
950 struct scatterlist
*sg
, int n_hw_ents
)
953 struct device
*controller
;
957 || !(controller
= bus
->controller
)
958 || !controller
->dma_mask
)
961 dma_sync_sg (controller
, sg
, n_hw_ents
,
962 usb_pipein (pipe
) ? DMA_FROM_DEVICE
: DMA_TO_DEVICE
);
967 * usb_buffer_unmap_sg - free DMA mapping(s) for a scatterlist
968 * @dev: device to which the scatterlist will be mapped
969 * @pipe: endpoint defining the mapping direction
970 * @sg: the scatterlist to unmap
971 * @n_hw_ents: the positive return value from usb_buffer_map_sg
973 * Reverses the effect of usb_buffer_map_sg().
975 void usb_buffer_unmap_sg (struct usb_device
*dev
, unsigned pipe
,
976 struct scatterlist
*sg
, int n_hw_ents
)
979 struct device
*controller
;
983 || !(controller
= bus
->controller
)
984 || !controller
->dma_mask
)
987 dma_unmap_sg (controller
, sg
, n_hw_ents
,
988 usb_pipein (pipe
) ? DMA_FROM_DEVICE
: DMA_TO_DEVICE
);
991 static int verify_suspended(struct device
*dev
, void *unused
)
993 if (dev
->driver
== NULL
)
995 return (dev
->power
.power_state
.event
== PM_EVENT_ON
) ? -EBUSY
: 0;
998 static int usb_generic_suspend(struct device
*dev
, pm_message_t message
)
1000 struct usb_interface
*intf
;
1001 struct usb_driver
*driver
;
1004 /* USB devices enter SUSPEND state through their hubs, but can be
1005 * marked for FREEZE as soon as their children are already idled.
1006 * But those semantics are useless, so we equate the two (sigh).
1008 if (dev
->driver
== &usb_generic_driver
) {
1009 if (dev
->power
.power_state
.event
== message
.event
)
1011 /* we need to rule out bogus requests through sysfs */
1012 status
= device_for_each_child(dev
, NULL
, verify_suspended
);
1015 return usb_suspend_device (to_usb_device(dev
));
1018 if ((dev
->driver
== NULL
) ||
1019 (dev
->driver_data
== &usb_generic_driver_data
))
1022 intf
= to_usb_interface(dev
);
1023 driver
= to_usb_driver(dev
->driver
);
1025 /* with no hardware, USB interfaces only use FREEZE and ON states */
1026 if (!is_active(intf
))
1029 if (driver
->suspend
&& driver
->resume
) {
1030 status
= driver
->suspend(intf
, message
);
1032 dev_err(dev
, "%s error %d\n", "suspend", status
);
1034 mark_quiesced(intf
);
1036 // FIXME else if there's no suspend method, disconnect...
1037 dev_warn(dev
, "no suspend for driver %s?\n", driver
->name
);
1038 mark_quiesced(intf
);
1044 static int usb_generic_resume(struct device
*dev
)
1046 struct usb_interface
*intf
;
1047 struct usb_driver
*driver
;
1048 struct usb_device
*udev
;
1051 if (dev
->power
.power_state
.event
== PM_EVENT_ON
)
1054 /* mark things as "on" immediately, no matter what errors crop up */
1055 dev
->power
.power_state
.event
= PM_EVENT_ON
;
1057 /* devices resume through their hubs */
1058 if (dev
->driver
== &usb_generic_driver
) {
1059 udev
= to_usb_device(dev
);
1060 if (udev
->state
== USB_STATE_NOTATTACHED
)
1062 return usb_resume_device (to_usb_device(dev
));
1065 if ((dev
->driver
== NULL
) ||
1066 (dev
->driver_data
== &usb_generic_driver_data
)) {
1067 dev
->power
.power_state
.event
= PM_EVENT_FREEZE
;
1071 intf
= to_usb_interface(dev
);
1072 driver
= to_usb_driver(dev
->driver
);
1074 udev
= interface_to_usbdev(intf
);
1075 if (udev
->state
== USB_STATE_NOTATTACHED
)
1078 /* if driver was suspended, it has a resume method;
1079 * however, sysfs can wrongly mark things as suspended
1080 * (on the "no suspend method" FIXME path above)
1082 if (driver
->resume
) {
1083 status
= driver
->resume(intf
);
1085 dev_err(dev
, "%s error %d\n", "resume", status
);
1086 mark_quiesced(intf
);
1089 dev_warn(dev
, "no resume for driver %s?\n", driver
->name
);
1093 struct bus_type usb_bus_type
= {
1095 .match
= usb_device_match
,
1096 .uevent
= usb_uevent
,
1097 .suspend
= usb_generic_suspend
,
1098 .resume
= usb_generic_resume
,
1101 /* format to disable USB on kernel command line is: nousb */
1102 __module_param_call("", nousb
, param_set_bool
, param_get_bool
, &nousb
, 0444);
1105 * for external read access to <nousb>
1107 int usb_disabled(void)
1115 static int __init
usb_init(void)
1119 pr_info ("%s: USB support disabled\n", usbcore_name
);
1123 retval
= bus_register(&usb_bus_type
);
1126 retval
= usb_host_init();
1128 goto host_init_failed
;
1129 retval
= usb_major_init();
1131 goto major_init_failed
;
1132 retval
= usb_register(&usbfs_driver
);
1134 goto driver_register_failed
;
1135 retval
= usbdev_init();
1137 goto usbdevice_init_failed
;
1138 retval
= usbfs_init();
1140 goto fs_init_failed
;
1141 retval
= usb_hub_init();
1143 goto hub_init_failed
;
1144 retval
= driver_register(&usb_generic_driver
);
1153 usbdevice_init_failed
:
1154 usb_deregister(&usbfs_driver
);
1155 driver_register_failed
:
1156 usb_major_cleanup();
1160 bus_unregister(&usb_bus_type
);
1168 static void __exit
usb_exit(void)
1170 /* This will matter if shutdown/reboot does exitcalls. */
1174 driver_unregister(&usb_generic_driver
);
1175 usb_major_cleanup();
1177 usb_deregister(&usbfs_driver
);
1181 bus_unregister(&usb_bus_type
);
1184 subsys_initcall(usb_init
);
1185 module_exit(usb_exit
);
1188 * USB may be built into the kernel or be built as modules.
1189 * These symbols are exported for device (or host controller)
1190 * driver modules to use.
1193 EXPORT_SYMBOL(usb_disabled
);
1195 EXPORT_SYMBOL_GPL(usb_get_intf
);
1196 EXPORT_SYMBOL_GPL(usb_put_intf
);
1198 EXPORT_SYMBOL(usb_put_dev
);
1199 EXPORT_SYMBOL(usb_get_dev
);
1200 EXPORT_SYMBOL(usb_hub_tt_clear_buffer
);
1202 EXPORT_SYMBOL(usb_lock_device_for_reset
);
1204 EXPORT_SYMBOL(usb_driver_claim_interface
);
1205 EXPORT_SYMBOL(usb_driver_release_interface
);
1206 EXPORT_SYMBOL(usb_find_interface
);
1207 EXPORT_SYMBOL(usb_ifnum_to_if
);
1208 EXPORT_SYMBOL(usb_altnum_to_altsetting
);
1210 EXPORT_SYMBOL(usb_reset_device
);
1211 EXPORT_SYMBOL(usb_reset_composite_device
);
1213 EXPORT_SYMBOL(__usb_get_extra_descriptor
);
1215 EXPORT_SYMBOL(usb_find_device
);
1216 EXPORT_SYMBOL(usb_get_current_frame_number
);
1218 EXPORT_SYMBOL (usb_buffer_alloc
);
1219 EXPORT_SYMBOL (usb_buffer_free
);
1222 EXPORT_SYMBOL (usb_buffer_map
);
1223 EXPORT_SYMBOL (usb_buffer_dmasync
);
1224 EXPORT_SYMBOL (usb_buffer_unmap
);
1227 EXPORT_SYMBOL (usb_buffer_map_sg
);
1229 EXPORT_SYMBOL (usb_buffer_dmasync_sg
);
1231 EXPORT_SYMBOL (usb_buffer_unmap_sg
);
1233 MODULE_LICENSE("GPL");