4 * This driver supports USB CDC WCM Device Management.
6 * Copyright (c) 2007-2009 Oliver Neukum
8 * Some code taken from cdc-acm.c
10 * Released under the GPLv2.
12 * Many thanks to Carl Nordbeck
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/slab.h>
17 #include <linux/module.h>
18 #include <linux/mutex.h>
19 #include <linux/uaccess.h>
20 #include <linux/bitops.h>
21 #include <linux/poll.h>
22 #include <linux/usb.h>
23 #include <linux/usb/cdc.h>
24 #include <asm/byteorder.h>
25 #include <asm/unaligned.h>
26 #include <linux/usb/cdc-wdm.h>
31 #define DRIVER_VERSION "v0.03"
32 #define DRIVER_AUTHOR "Oliver Neukum"
33 #define DRIVER_DESC "USB Abstract Control Model driver for USB WCM Device Management"
35 #define HUAWEI_VENDOR_ID 0x12D1
37 static const struct usb_device_id wdm_ids
[] = {
39 .match_flags
= USB_DEVICE_ID_MATCH_INT_CLASS
|
40 USB_DEVICE_ID_MATCH_INT_SUBCLASS
,
41 .bInterfaceClass
= USB_CLASS_COMM
,
42 .bInterfaceSubClass
= USB_CDC_SUBCLASS_DMM
46 * Huawei E392, E398 and possibly other Qualcomm based modems
47 * embed the Qualcomm QMI protocol inside CDC on CDC ECM like
48 * control interfaces. Userspace access to this is required
49 * to configure the accompanying data interface
51 .match_flags
= USB_DEVICE_ID_MATCH_VENDOR
|
52 USB_DEVICE_ID_MATCH_INT_INFO
,
53 .idVendor
= HUAWEI_VENDOR_ID
,
54 .bInterfaceClass
= USB_CLASS_VENDOR_SPEC
,
55 .bInterfaceSubClass
= 1,
56 .bInterfaceProtocol
= 9, /* NOTE: CDC ECM control interface! */
61 MODULE_DEVICE_TABLE (usb
, wdm_ids
);
63 #define WDM_MINOR_BASE 176
67 #define WDM_DISCONNECTING 2
70 #define WDM_INT_STALL 5
71 #define WDM_POLL_RUNNING 6
72 #define WDM_RESPONDING 7
73 #define WDM_SUSPENDING 8
74 #define WDM_RESETTING 9
78 /* CDC-WMC r1.1 requires wMaxCommand to be "at least 256 decimal (0x100)" */
79 #define WDM_DEFAULT_BUFSIZE 256
81 static DEFINE_MUTEX(wdm_mutex
);
82 static DEFINE_SPINLOCK(wdm_device_list_lock
);
83 static LIST_HEAD(wdm_device_list
);
85 /* --- method tables --- */
88 u8
*inbuf
; /* buffer for response */
89 u8
*outbuf
; /* buffer for command */
90 u8
*sbuf
; /* buffer for status */
91 u8
*ubuf
; /* buffer for copy to user space */
96 struct usb_interface
*intf
;
97 struct usb_ctrlrequest
*orq
;
98 struct usb_ctrlrequest
*irq
;
114 wait_queue_head_t wait
;
115 struct work_struct rxwork
;
119 struct list_head device_list
;
120 int (*manage_power
)(struct usb_interface
*, int);
123 static struct usb_driver wdm_driver
;
125 /* return intfdata if we own the interface, else look up intf in the list */
126 static struct wdm_device
*wdm_find_device(struct usb_interface
*intf
)
128 struct wdm_device
*desc
= NULL
;
130 spin_lock(&wdm_device_list_lock
);
131 list_for_each_entry(desc
, &wdm_device_list
, device_list
)
132 if (desc
->intf
== intf
)
134 spin_unlock(&wdm_device_list_lock
);
139 static struct wdm_device
*wdm_find_device_by_minor(int minor
)
141 struct wdm_device
*desc
= NULL
;
143 spin_lock(&wdm_device_list_lock
);
144 list_for_each_entry(desc
, &wdm_device_list
, device_list
)
145 if (desc
->intf
->minor
== minor
)
147 spin_unlock(&wdm_device_list_lock
);
152 /* --- callbacks --- */
153 static void wdm_out_callback(struct urb
*urb
)
155 struct wdm_device
*desc
;
157 spin_lock(&desc
->iuspin
);
158 desc
->werr
= urb
->status
;
159 spin_unlock(&desc
->iuspin
);
160 clear_bit(WDM_IN_USE
, &desc
->flags
);
162 wake_up(&desc
->wait
);
165 static void wdm_in_callback(struct urb
*urb
)
167 struct wdm_device
*desc
= urb
->context
;
168 int status
= urb
->status
;
170 spin_lock(&desc
->iuspin
);
171 clear_bit(WDM_RESPONDING
, &desc
->flags
);
176 dev_dbg(&desc
->intf
->dev
,
177 "nonzero urb status received: -ENOENT");
180 dev_dbg(&desc
->intf
->dev
,
181 "nonzero urb status received: -ECONNRESET");
184 dev_dbg(&desc
->intf
->dev
,
185 "nonzero urb status received: -ESHUTDOWN");
188 dev_err(&desc
->intf
->dev
,
189 "nonzero urb status received: -EPIPE\n");
192 dev_err(&desc
->intf
->dev
,
193 "Unexpected error %d\n", status
);
199 desc
->reslength
= urb
->actual_length
;
200 memmove(desc
->ubuf
+ desc
->length
, desc
->inbuf
, desc
->reslength
);
201 desc
->length
+= desc
->reslength
;
203 wake_up(&desc
->wait
);
205 set_bit(WDM_READ
, &desc
->flags
);
206 spin_unlock(&desc
->iuspin
);
209 static void wdm_int_callback(struct urb
*urb
)
212 int status
= urb
->status
;
213 struct wdm_device
*desc
;
214 struct usb_cdc_notification
*dr
;
217 dr
= (struct usb_cdc_notification
*)desc
->sbuf
;
226 set_bit(WDM_INT_STALL
, &desc
->flags
);
227 dev_err(&desc
->intf
->dev
, "Stall on int endpoint\n");
228 goto sw
; /* halt is cleared in work */
230 dev_err(&desc
->intf
->dev
,
231 "nonzero urb status received: %d\n", status
);
236 if (urb
->actual_length
< sizeof(struct usb_cdc_notification
)) {
237 dev_err(&desc
->intf
->dev
, "wdm_int_callback - %d bytes\n",
242 switch (dr
->bNotificationType
) {
243 case USB_CDC_NOTIFY_RESPONSE_AVAILABLE
:
244 dev_dbg(&desc
->intf
->dev
,
245 "NOTIFY_RESPONSE_AVAILABLE received: index %d len %d",
246 dr
->wIndex
, dr
->wLength
);
249 case USB_CDC_NOTIFY_NETWORK_CONNECTION
:
251 dev_dbg(&desc
->intf
->dev
,
252 "NOTIFY_NETWORK_CONNECTION %s network",
253 dr
->wValue
? "connected to" : "disconnected from");
256 clear_bit(WDM_POLL_RUNNING
, &desc
->flags
);
257 dev_err(&desc
->intf
->dev
,
258 "unknown notification %d received: index %d len %d\n",
259 dr
->bNotificationType
, dr
->wIndex
, dr
->wLength
);
263 spin_lock(&desc
->iuspin
);
264 clear_bit(WDM_READ
, &desc
->flags
);
265 set_bit(WDM_RESPONDING
, &desc
->flags
);
266 if (!test_bit(WDM_DISCONNECTING
, &desc
->flags
)
267 && !test_bit(WDM_SUSPENDING
, &desc
->flags
)) {
268 rv
= usb_submit_urb(desc
->response
, GFP_ATOMIC
);
269 dev_dbg(&desc
->intf
->dev
, "%s: usb_submit_urb %d",
272 spin_unlock(&desc
->iuspin
);
274 clear_bit(WDM_RESPONDING
, &desc
->flags
);
279 rv
= schedule_work(&desc
->rxwork
);
281 dev_err(&desc
->intf
->dev
,
282 "Cannot schedule work\n");
286 rv
= usb_submit_urb(urb
, GFP_ATOMIC
);
288 dev_err(&desc
->intf
->dev
,
289 "%s - usb_submit_urb failed with result %d\n",
294 static void kill_urbs(struct wdm_device
*desc
)
296 /* the order here is essential */
297 usb_kill_urb(desc
->command
);
298 usb_kill_urb(desc
->validity
);
299 usb_kill_urb(desc
->response
);
302 static void free_urbs(struct wdm_device
*desc
)
304 usb_free_urb(desc
->validity
);
305 usb_free_urb(desc
->response
);
306 usb_free_urb(desc
->command
);
309 static void cleanup(struct wdm_device
*desc
)
311 spin_lock(&wdm_device_list_lock
);
312 list_del(&desc
->device_list
);
313 spin_unlock(&wdm_device_list_lock
);
323 static ssize_t wdm_write
324 (struct file
*file
, const char __user
*buffer
, size_t count
, loff_t
*ppos
)
327 int rv
= -EMSGSIZE
, r
, we
;
328 struct wdm_device
*desc
= file
->private_data
;
329 struct usb_ctrlrequest
*req
;
331 if (count
> desc
->wMaxCommand
)
332 count
= desc
->wMaxCommand
;
334 spin_lock_irq(&desc
->iuspin
);
337 spin_unlock_irq(&desc
->iuspin
);
341 desc
->outbuf
= buf
= kmalloc(count
, GFP_KERNEL
);
347 r
= copy_from_user(buf
, buffer
, count
);
354 /* concurrent writes and disconnect */
355 r
= mutex_lock_interruptible(&desc
->wlock
);
362 if (test_bit(WDM_DISCONNECTING
, &desc
->flags
)) {
368 r
= usb_autopm_get_interface(desc
->intf
);
374 if (!(file
->f_flags
& O_NONBLOCK
))
375 r
= wait_event_interruptible(desc
->wait
, !test_bit(WDM_IN_USE
,
378 if (test_bit(WDM_IN_USE
, &desc
->flags
))
381 if (test_bit(WDM_RESETTING
, &desc
->flags
))
390 usb_fill_control_urb(
392 interface_to_usbdev(desc
->intf
),
393 /* using common endpoint 0 */
394 usb_sndctrlpipe(interface_to_usbdev(desc
->intf
), 0),
395 (unsigned char *)req
,
402 req
->bRequestType
= (USB_DIR_OUT
| USB_TYPE_CLASS
|
403 USB_RECIP_INTERFACE
);
404 req
->bRequest
= USB_CDC_SEND_ENCAPSULATED_COMMAND
;
406 req
->wIndex
= desc
->inum
;
407 req
->wLength
= cpu_to_le16(count
);
408 set_bit(WDM_IN_USE
, &desc
->flags
);
410 rv
= usb_submit_urb(desc
->command
, GFP_KERNEL
);
413 clear_bit(WDM_IN_USE
, &desc
->flags
);
414 dev_err(&desc
->intf
->dev
, "Tx URB error: %d\n", rv
);
416 dev_dbg(&desc
->intf
->dev
, "Tx URB has been submitted index=%d",
420 usb_autopm_put_interface(desc
->intf
);
422 mutex_unlock(&desc
->wlock
);
424 return rv
< 0 ? rv
: count
;
427 static ssize_t wdm_read
428 (struct file
*file
, char __user
*buffer
, size_t count
, loff_t
*ppos
)
432 struct wdm_device
*desc
= file
->private_data
;
435 rv
= mutex_lock_interruptible(&desc
->rlock
); /*concurrent reads */
439 cntr
= ACCESS_ONCE(desc
->length
);
443 if (test_bit(WDM_DISCONNECTING
, &desc
->flags
)) {
448 if (file
->f_flags
& O_NONBLOCK
) {
449 if (!test_bit(WDM_READ
, &desc
->flags
)) {
450 rv
= cntr
? cntr
: -EAGAIN
;
455 rv
= wait_event_interruptible(desc
->wait
,
456 test_bit(WDM_READ
, &desc
->flags
));
459 /* may have happened while we slept */
460 if (test_bit(WDM_DISCONNECTING
, &desc
->flags
)) {
464 if (test_bit(WDM_RESETTING
, &desc
->flags
)) {
468 usb_mark_last_busy(interface_to_usbdev(desc
->intf
));
474 spin_lock_irq(&desc
->iuspin
);
476 if (desc
->rerr
) { /* read completed, error happened */
478 spin_unlock_irq(&desc
->iuspin
);
483 * recheck whether we've lost the race
484 * against the completion handler
486 if (!test_bit(WDM_READ
, &desc
->flags
)) { /* lost race */
487 spin_unlock_irq(&desc
->iuspin
);
490 if (!desc
->reslength
) { /* zero length read */
491 spin_unlock_irq(&desc
->iuspin
);
495 spin_unlock_irq(&desc
->iuspin
);
500 rv
= copy_to_user(buffer
, desc
->ubuf
, cntr
);
506 spin_lock_irq(&desc
->iuspin
);
508 for (i
= 0; i
< desc
->length
- cntr
; i
++)
509 desc
->ubuf
[i
] = desc
->ubuf
[i
+ cntr
];
511 desc
->length
-= cntr
;
512 /* in case we had outstanding data */
514 clear_bit(WDM_READ
, &desc
->flags
);
516 spin_unlock_irq(&desc
->iuspin
);
521 mutex_unlock(&desc
->rlock
);
525 static int wdm_flush(struct file
*file
, fl_owner_t id
)
527 struct wdm_device
*desc
= file
->private_data
;
529 wait_event(desc
->wait
, !test_bit(WDM_IN_USE
, &desc
->flags
));
531 dev_err(&desc
->intf
->dev
, "Error in flush path: %d\n",
537 static unsigned int wdm_poll(struct file
*file
, struct poll_table_struct
*wait
)
539 struct wdm_device
*desc
= file
->private_data
;
541 unsigned int mask
= 0;
543 spin_lock_irqsave(&desc
->iuspin
, flags
);
544 if (test_bit(WDM_DISCONNECTING
, &desc
->flags
)) {
546 spin_unlock_irqrestore(&desc
->iuspin
, flags
);
549 if (test_bit(WDM_READ
, &desc
->flags
))
550 mask
= POLLIN
| POLLRDNORM
;
551 if (desc
->rerr
|| desc
->werr
)
553 if (!test_bit(WDM_IN_USE
, &desc
->flags
))
554 mask
|= POLLOUT
| POLLWRNORM
;
555 spin_unlock_irqrestore(&desc
->iuspin
, flags
);
557 poll_wait(file
, &desc
->wait
, wait
);
563 static int wdm_open(struct inode
*inode
, struct file
*file
)
565 int minor
= iminor(inode
);
567 struct usb_interface
*intf
;
568 struct wdm_device
*desc
;
570 mutex_lock(&wdm_mutex
);
571 desc
= wdm_find_device_by_minor(minor
);
576 if (test_bit(WDM_DISCONNECTING
, &desc
->flags
))
578 file
->private_data
= desc
;
580 rv
= usb_autopm_get_interface(desc
->intf
);
582 dev_err(&desc
->intf
->dev
, "Error autopm - %d\n", rv
);
586 /* using write lock to protect desc->count */
587 mutex_lock(&desc
->wlock
);
588 if (!desc
->count
++) {
591 rv
= usb_submit_urb(desc
->validity
, GFP_KERNEL
);
594 dev_err(&desc
->intf
->dev
,
595 "Error submitting int urb - %d\n", rv
);
600 mutex_unlock(&desc
->wlock
);
601 if (desc
->count
== 1)
602 desc
->manage_power(intf
, 1);
603 usb_autopm_put_interface(desc
->intf
);
605 mutex_unlock(&wdm_mutex
);
609 static int wdm_release(struct inode
*inode
, struct file
*file
)
611 struct wdm_device
*desc
= file
->private_data
;
613 mutex_lock(&wdm_mutex
);
615 /* using write lock to protect desc->count */
616 mutex_lock(&desc
->wlock
);
618 mutex_unlock(&desc
->wlock
);
621 dev_dbg(&desc
->intf
->dev
, "wdm_release: cleanup");
623 if (!test_bit(WDM_DISCONNECTING
, &desc
->flags
))
624 desc
->manage_power(desc
->intf
, 0);
626 mutex_unlock(&wdm_mutex
);
630 static const struct file_operations wdm_fops
= {
631 .owner
= THIS_MODULE
,
636 .release
= wdm_release
,
638 .llseek
= noop_llseek
,
641 static struct usb_class_driver wdm_class
= {
644 .minor_base
= WDM_MINOR_BASE
,
647 /* --- error handling --- */
648 static void wdm_rxwork(struct work_struct
*work
)
650 struct wdm_device
*desc
= container_of(work
, struct wdm_device
, rxwork
);
654 spin_lock_irqsave(&desc
->iuspin
, flags
);
655 if (test_bit(WDM_DISCONNECTING
, &desc
->flags
)) {
656 spin_unlock_irqrestore(&desc
->iuspin
, flags
);
658 spin_unlock_irqrestore(&desc
->iuspin
, flags
);
659 rv
= usb_submit_urb(desc
->response
, GFP_KERNEL
);
660 if (rv
< 0 && rv
!= -EPERM
) {
661 spin_lock_irqsave(&desc
->iuspin
, flags
);
662 if (!test_bit(WDM_DISCONNECTING
, &desc
->flags
))
663 schedule_work(&desc
->rxwork
);
664 spin_unlock_irqrestore(&desc
->iuspin
, flags
);
669 /* --- hotplug --- */
671 static int wdm_create(struct usb_interface
*intf
, struct usb_endpoint_descriptor
*ep
,
672 u16 bufsize
, int (*manage_power
)(struct usb_interface
*, int))
675 struct wdm_device
*desc
;
677 desc
= kzalloc(sizeof(struct wdm_device
), GFP_KERNEL
);
680 INIT_LIST_HEAD(&desc
->device_list
);
681 mutex_init(&desc
->rlock
);
682 mutex_init(&desc
->wlock
);
683 spin_lock_init(&desc
->iuspin
);
684 init_waitqueue_head(&desc
->wait
);
685 desc
->wMaxCommand
= bufsize
;
686 /* this will be expanded and needed in hardware endianness */
687 desc
->inum
= cpu_to_le16((u16
)intf
->cur_altsetting
->desc
.bInterfaceNumber
);
689 INIT_WORK(&desc
->rxwork
, wdm_rxwork
);
692 if (!usb_endpoint_is_int_in(ep
))
695 desc
->wMaxPacketSize
= usb_endpoint_maxp(ep
);
697 desc
->orq
= kmalloc(sizeof(struct usb_ctrlrequest
), GFP_KERNEL
);
700 desc
->irq
= kmalloc(sizeof(struct usb_ctrlrequest
), GFP_KERNEL
);
704 desc
->validity
= usb_alloc_urb(0, GFP_KERNEL
);
708 desc
->response
= usb_alloc_urb(0, GFP_KERNEL
);
712 desc
->command
= usb_alloc_urb(0, GFP_KERNEL
);
716 desc
->ubuf
= kmalloc(desc
->wMaxCommand
, GFP_KERNEL
);
720 desc
->sbuf
= kmalloc(desc
->wMaxPacketSize
, GFP_KERNEL
);
724 desc
->inbuf
= kmalloc(desc
->wMaxCommand
, GFP_KERNEL
);
730 interface_to_usbdev(intf
),
731 usb_rcvintpipe(interface_to_usbdev(intf
), ep
->bEndpointAddress
),
733 desc
->wMaxPacketSize
,
739 desc
->irq
->bRequestType
= (USB_DIR_IN
| USB_TYPE_CLASS
| USB_RECIP_INTERFACE
);
740 desc
->irq
->bRequest
= USB_CDC_GET_ENCAPSULATED_RESPONSE
;
741 desc
->irq
->wValue
= 0;
742 desc
->irq
->wIndex
= desc
->inum
;
743 desc
->irq
->wLength
= cpu_to_le16(desc
->wMaxCommand
);
745 usb_fill_control_urb(
747 interface_to_usbdev(intf
),
748 /* using common endpoint 0 */
749 usb_rcvctrlpipe(interface_to_usbdev(desc
->intf
), 0),
750 (unsigned char *)desc
->irq
,
757 desc
->manage_power
= manage_power
;
759 spin_lock(&wdm_device_list_lock
);
760 list_add(&desc
->device_list
, &wdm_device_list
);
761 spin_unlock(&wdm_device_list_lock
);
763 rv
= usb_register_dev(intf
, &wdm_class
);
767 dev_info(&intf
->dev
, "%s: USB WDM device\n", dev_name(intf
->usb_dev
));
775 static int wdm_manage_power(struct usb_interface
*intf
, int on
)
777 /* need autopm_get/put here to ensure the usbcore sees the new value */
778 int rv
= usb_autopm_get_interface(intf
);
782 intf
->needs_remote_wakeup
= on
;
783 usb_autopm_put_interface(intf
);
788 static int wdm_probe(struct usb_interface
*intf
, const struct usb_device_id
*id
)
791 struct usb_host_interface
*iface
;
792 struct usb_endpoint_descriptor
*ep
;
793 struct usb_cdc_dmm_desc
*dmhd
;
794 u8
*buffer
= intf
->altsetting
->extra
;
795 int buflen
= intf
->altsetting
->extralen
;
796 u16 maxcom
= WDM_DEFAULT_BUFSIZE
;
801 if (buffer
[1] != USB_DT_CS_INTERFACE
) {
802 dev_err(&intf
->dev
, "skipping garbage\n");
807 case USB_CDC_HEADER_TYPE
:
809 case USB_CDC_DMM_TYPE
:
810 dmhd
= (struct usb_cdc_dmm_desc
*)buffer
;
811 maxcom
= le16_to_cpu(dmhd
->wMaxCommand
);
813 "Finding maximum buffer length: %d", maxcom
);
817 "Ignoring extra header, type %d, length %d\n",
818 buffer
[2], buffer
[0]);
826 iface
= intf
->cur_altsetting
;
827 if (iface
->desc
.bNumEndpoints
!= 1)
829 ep
= &iface
->endpoint
[0].desc
;
831 rv
= wdm_create(intf
, ep
, maxcom
, &wdm_manage_power
);
838 * usb_cdc_wdm_register - register a WDM subdriver
839 * @intf: usb interface the subdriver will associate with
840 * @ep: interrupt endpoint to monitor for notifications
841 * @bufsize: maximum message size to support for read/write
843 * Create WDM usb class character device and associate it with intf
844 * without binding, allowing another driver to manage the interface.
846 * The subdriver will manage the given interrupt endpoint exclusively
847 * and will issue control requests referring to the given intf. It
848 * will otherwise avoid interferring, and in particular not do
849 * usb_set_intfdata/usb_get_intfdata on intf.
851 * The return value is a pointer to the subdriver's struct usb_driver.
852 * The registering driver is responsible for calling this subdriver's
853 * disconnect, suspend, resume, pre_reset and post_reset methods from
856 struct usb_driver
*usb_cdc_wdm_register(struct usb_interface
*intf
,
857 struct usb_endpoint_descriptor
*ep
,
859 int (*manage_power
)(struct usb_interface
*, int))
863 rv
= wdm_create(intf
, ep
, bufsize
, manage_power
);
871 EXPORT_SYMBOL(usb_cdc_wdm_register
);
873 static void wdm_disconnect(struct usb_interface
*intf
)
875 struct wdm_device
*desc
;
878 usb_deregister_dev(intf
, &wdm_class
);
879 desc
= wdm_find_device(intf
);
880 mutex_lock(&wdm_mutex
);
882 /* the spinlock makes sure no new urbs are generated in the callbacks */
883 spin_lock_irqsave(&desc
->iuspin
, flags
);
884 set_bit(WDM_DISCONNECTING
, &desc
->flags
);
885 set_bit(WDM_READ
, &desc
->flags
);
886 /* to terminate pending flushes */
887 clear_bit(WDM_IN_USE
, &desc
->flags
);
888 spin_unlock_irqrestore(&desc
->iuspin
, flags
);
889 wake_up_all(&desc
->wait
);
890 mutex_lock(&desc
->rlock
);
891 mutex_lock(&desc
->wlock
);
893 cancel_work_sync(&desc
->rxwork
);
894 mutex_unlock(&desc
->wlock
);
895 mutex_unlock(&desc
->rlock
);
898 mutex_unlock(&wdm_mutex
);
902 static int wdm_suspend(struct usb_interface
*intf
, pm_message_t message
)
904 struct wdm_device
*desc
= wdm_find_device(intf
);
907 dev_dbg(&desc
->intf
->dev
, "wdm%d_suspend\n", intf
->minor
);
909 /* if this is an autosuspend the caller does the locking */
910 if (!PMSG_IS_AUTO(message
)) {
911 mutex_lock(&desc
->rlock
);
912 mutex_lock(&desc
->wlock
);
914 spin_lock_irq(&desc
->iuspin
);
916 if (PMSG_IS_AUTO(message
) &&
917 (test_bit(WDM_IN_USE
, &desc
->flags
)
918 || test_bit(WDM_RESPONDING
, &desc
->flags
))) {
919 spin_unlock_irq(&desc
->iuspin
);
923 set_bit(WDM_SUSPENDING
, &desc
->flags
);
924 spin_unlock_irq(&desc
->iuspin
);
925 /* callback submits work - order is essential */
927 cancel_work_sync(&desc
->rxwork
);
929 if (!PMSG_IS_AUTO(message
)) {
930 mutex_unlock(&desc
->wlock
);
931 mutex_unlock(&desc
->rlock
);
938 static int recover_from_urb_loss(struct wdm_device
*desc
)
943 rv
= usb_submit_urb(desc
->validity
, GFP_NOIO
);
945 dev_err(&desc
->intf
->dev
,
946 "Error resume submitting int urb - %d\n", rv
);
952 static int wdm_resume(struct usb_interface
*intf
)
954 struct wdm_device
*desc
= wdm_find_device(intf
);
957 dev_dbg(&desc
->intf
->dev
, "wdm%d_resume\n", intf
->minor
);
959 clear_bit(WDM_SUSPENDING
, &desc
->flags
);
960 rv
= recover_from_urb_loss(desc
);
966 static int wdm_pre_reset(struct usb_interface
*intf
)
968 struct wdm_device
*desc
= wdm_find_device(intf
);
971 * we notify everybody using poll of
972 * an exceptional situation
973 * must be done before recovery lest a spontaneous
974 * message from the device is lost
976 spin_lock_irq(&desc
->iuspin
);
977 set_bit(WDM_RESETTING
, &desc
->flags
); /* inform read/write */
978 set_bit(WDM_READ
, &desc
->flags
); /* unblock read */
979 clear_bit(WDM_IN_USE
, &desc
->flags
); /* unblock write */
981 spin_unlock_irq(&desc
->iuspin
);
982 wake_up_all(&desc
->wait
);
983 mutex_lock(&desc
->rlock
);
984 mutex_lock(&desc
->wlock
);
986 cancel_work_sync(&desc
->rxwork
);
990 static int wdm_post_reset(struct usb_interface
*intf
)
992 struct wdm_device
*desc
= wdm_find_device(intf
);
995 clear_bit(WDM_RESETTING
, &desc
->flags
);
996 rv
= recover_from_urb_loss(desc
);
997 mutex_unlock(&desc
->wlock
);
998 mutex_unlock(&desc
->rlock
);
1002 static struct usb_driver wdm_driver
= {
1005 .disconnect
= wdm_disconnect
,
1007 .suspend
= wdm_suspend
,
1008 .resume
= wdm_resume
,
1009 .reset_resume
= wdm_resume
,
1011 .pre_reset
= wdm_pre_reset
,
1012 .post_reset
= wdm_post_reset
,
1013 .id_table
= wdm_ids
,
1014 .supports_autosuspend
= 1,
1017 module_usb_driver(wdm_driver
);
1019 MODULE_AUTHOR(DRIVER_AUTHOR
);
1020 MODULE_DESCRIPTION(DRIVER_DESC
);
1021 MODULE_LICENSE("GPL");