2 * Frontier Designs Alphatrack driver
4 * Copyright (C) 2007 Michael Taht (m@taht.net)
6 * Based on the usbled driver and ldusb drivers by
8 * Copyright (C) 2004 Greg Kroah-Hartman (greg@kroah.com)
9 * Copyright (C) 2005 Michael Hund <mhund@ld-didactic.de>
11 * The ldusb driver was, in turn, derived from Lego USB Tower driver
12 * Copyright (C) 2003 David Glance <advidgsf@sourceforge.net>
13 * 2001-2004 Juergen Stuber <starblue@users.sourceforge.net>
15 * This program is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU General Public License as
17 * published by the Free Software Foundation, version 2.
22 * This driver uses a ring buffer for time critical reading of
23 * interrupt in reports and provides read and write methods for
24 * raw interrupt reports.
27 /* Note: this currently uses a dumb ringbuffer for reads and writes.
28 * A more optimal driver would cache and kill off outstanding urbs that are
29 * now invalid, and ignore ones that already were in the queue but valid
30 * as we only have 30 commands for the alphatrack. In particular this is
31 * key for getting lights to flash in time as otherwise many commands
32 * can be buffered up before the light change makes it to the interface.
35 #include <linux/kernel.h>
36 #include <linux/errno.h>
37 #include <linux/init.h>
38 #include <linux/slab.h>
39 #include <linux/module.h>
40 #include <linux/kobject.h>
41 #include <linux/mutex.h>
42 #include <linux/version.h>
44 #include <asm/uaccess.h>
45 #include <linux/input.h>
46 #include <linux/usb.h>
47 #include <linux/poll.h>
49 #include "surface_sysfs.h"
51 /* make this work on older kernel versions */
53 #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 19)
54 #include "frontier_compat.h"
55 #endif /* older kernel versions */
57 #include "alphatrack.h"
59 #define VENDOR_ID 0x165b
60 #define PRODUCT_ID 0xfad1
62 #ifdef CONFIG_USB_DYNAMIC_MINORS
63 #define USB_ALPHATRACK_MINOR_BASE 0
65 // FIXME 176 - is another driver's minor - apply for that
66 // #define USB_ALPHATRACK_MINOR_BASE 177
67 #define USB_ALPHATRACK_MINOR_BASE 176
70 /* table of devices that work with this driver */
71 static struct usb_device_id usb_alphatrack_table
[] = {
72 { USB_DEVICE(VENDOR_ID
, PRODUCT_ID
) },
73 { } /* Terminating entry */
76 MODULE_DEVICE_TABLE(usb
, usb_alphatrack_table
);
77 MODULE_VERSION("0.40");
78 MODULE_AUTHOR("Mike Taht <m@taht.net>");
79 MODULE_DESCRIPTION("Alphatrack USB Driver");
80 MODULE_LICENSE("GPL");
81 MODULE_SUPPORTED_DEVICE("Frontier Designs Alphatrack Control Surface");
83 /* These aren't done yet */
85 #define SUPPRESS_EXTRA_ONLINE_EVENTS 0
86 #define BUFFERED_WRITES 0
87 #define SUPPRESS_EXTRA_OFFLINE_EVENTS 0
88 #define COMPRESS_FADER_EVENTS 0
90 #define BUFFERED_READS 1
91 #define RING_BUFFER_SIZE 512
92 #define WRITE_BUFFER_SIZE 34
93 #define ALPHATRACK_USB_TIMEOUT 10
94 #define OUTPUT_CMD_SIZE 8
95 #define INPUT_CMD_SIZE 12
100 /* Use our own dbg macro */
101 #define dbg_info(dev, format, arg...) do { if (debug) dev_info(dev , format , ## arg); } while (0)
104 #define alphatrack_ocmd_info(dev, cmd, format, arg...) do { if (debug) ocmd_info(dev , cmd , format, ## arg); } while (0)
106 #define alphatrack_icmd_info(dev, cmd, format, arg...) do { if (debug) icmd_info(dev , cmd, format, ## arg); } while (0)
108 #define alphatrack_ocmd_info(dev, cmd, format, arg...)
110 #define alphatrack_icmd_info(dev, cmd, format, arg...)
114 /* Module parameters */
116 module_param(debug
, int, S_IRUGO
| S_IWUSR
);
117 MODULE_PARM_DESC(debug
, "Debug enabled or not");
119 /* All interrupt in transfers are collected in a ring buffer to
120 * avoid racing conditions and get better performance of the driver.
123 static int ring_buffer_size
= RING_BUFFER_SIZE
;
125 module_param(ring_buffer_size
, int, S_IRUGO
);
126 MODULE_PARM_DESC(ring_buffer_size
, "Read ring buffer size");
128 /* The write_buffer can one day contain more than one interrupt out transfer.
131 static int write_buffer_size
= WRITE_BUFFER_SIZE
;
132 module_param(write_buffer_size
, int, S_IRUGO
);
133 MODULE_PARM_DESC(write_buffer_size
, "Write buffer size");
136 * Increase the interval for debugging purposes.
137 * or set to 1 to use the standard interval from the endpoint descriptors.
140 static int min_interrupt_in_interval
= ALPHATRACK_USB_TIMEOUT
;
141 module_param(min_interrupt_in_interval
, int, 0);
142 MODULE_PARM_DESC(min_interrupt_in_interval
, "Minimum interrupt in interval in ms");
144 static int min_interrupt_out_interval
= ALPHATRACK_USB_TIMEOUT
;
145 module_param(min_interrupt_out_interval
, int, 0);
146 MODULE_PARM_DESC(min_interrupt_out_interval
, "Minimum interrupt out interval in ms");
150 /* Structure to hold all of our device specific stuff */
152 struct usb_alphatrack
{
153 struct semaphore sem
; /* locks this structure */
154 struct usb_interface
* intf
; /* save off the usb interface pointer */
155 int open_count
; /* number of times this port has been opened */
157 struct alphatrack_icmd (*ring_buffer
)[RING_BUFFER_SIZE
]; /* just make c happy */
158 struct alphatrack_ocmd (*write_buffer
)[WRITE_BUFFER_SIZE
]; /* just make c happy */
159 unsigned int ring_head
;
160 unsigned int ring_tail
;
162 wait_queue_head_t read_wait
;
163 wait_queue_head_t write_wait
;
165 unsigned char* interrupt_in_buffer
;
166 unsigned char* oldi_buffer
;
167 struct usb_endpoint_descriptor
* interrupt_in_endpoint
;
168 struct urb
* interrupt_in_urb
;
169 int interrupt_in_interval
;
170 size_t interrupt_in_endpoint_size
;
171 int interrupt_in_running
;
172 int interrupt_in_done
;
174 char* interrupt_out_buffer
;
175 struct usb_endpoint_descriptor
* interrupt_out_endpoint
;
176 struct urb
* interrupt_out_urb
;
177 int interrupt_out_interval
;
178 size_t interrupt_out_endpoint_size
;
179 int interrupt_out_busy
;
181 atomic_t writes_pending
;
182 int event
; /* alternate interface to events */
183 int fader
; /* 10 bits */
184 int lights
; /* 23 bits */
185 unsigned char dump_state
; /* 0 if disabled 1 if enabled */
186 unsigned char enable
; /* 0 if disabled 1 if enabled */
187 unsigned char offline
; /* if the device is out of range or asleep */
188 unsigned char verbose
; /* be verbose in error reporting */
189 unsigned char last_cmd
[OUTPUT_CMD_SIZE
];
190 unsigned char screen
[32];
193 /* prevent races between open() and disconnect() */
194 static DEFINE_MUTEX(disconnect_mutex
);
196 /* forward declaration */
198 static struct usb_driver usb_alphatrack_driver
;
200 static void icmd_info(struct usb_alphatrack
*dev
, char *cmd
, char *str
, char *a
) {
208 static void ocmd_info(struct usb_alphatrack
*dev
, char *cmd
, char *str
, char* a
) {
218 * usb_alphatrack_abort_transfers
219 * aborts transfers and frees associated data structures
221 static void usb_alphatrack_abort_transfers(struct usb_alphatrack
*dev
)
223 /* shutdown transfer */
224 if (dev
->interrupt_in_running
) {
225 dev
->interrupt_in_running
= 0;
227 usb_kill_urb(dev
->interrupt_in_urb
);
229 if (dev
->interrupt_out_busy
)
231 usb_kill_urb(dev
->interrupt_out_urb
);
235 * usb_alphatrack_delete
237 static void usb_alphatrack_delete(struct usb_alphatrack
*dev
)
239 usb_alphatrack_abort_transfers(dev
);
240 usb_free_urb(dev
->interrupt_in_urb
);
241 usb_free_urb(dev
->interrupt_out_urb
);
242 kfree(dev
->ring_buffer
);
243 kfree(dev
->interrupt_in_buffer
);
244 kfree(dev
->interrupt_out_buffer
);
245 kfree(dev
); // fixme oldi_buffer
249 * usb_alphatrack_interrupt_in_callback
252 static void usb_alphatrack_interrupt_in_callback(struct urb
*urb
)
254 struct usb_alphatrack
*dev
= urb
->context
;
255 unsigned int next_ring_head
;
260 if (urb
->status
== -ENOENT
||
261 urb
->status
== -ECONNRESET
||
262 urb
->status
== -ESHUTDOWN
) {
265 dbg_info(&dev
->intf
->dev
, "%s: nonzero status received: %d\n",
266 __FUNCTION__
, urb
->status
);
267 goto resubmit
; /* maybe we can recover */
271 if (urb
->actual_length
!= INPUT_CMD_SIZE
) {
272 dev_warn(&dev
->intf
->dev
,
273 "Urb length was %d bytes!! Do something intelligent \n", urb
->actual_length
);
275 alphatrack_ocmd_info(&dev
->intf
->dev
,&(*dev
->ring_buffer
)[dev
->ring_tail
].cmd
,"%s", "bla");
276 if(memcmp(dev
->interrupt_in_buffer
,dev
->oldi_buffer
,INPUT_CMD_SIZE
)==0) {
279 memcpy(dev
->oldi_buffer
,dev
->interrupt_in_buffer
,INPUT_CMD_SIZE
);
281 #if SUPPRESS_EXTRA_OFFLINE_EVENTS
282 if(dev
->offline
== 2 && dev
->interrupt_in_buffer
[1] == 0xff) { goto resubmit
; }
283 if(dev
->offline
== 1 && dev
->interrupt_in_buffer
[1] == 0xff) { dev
->offline
= 2; goto resubmit
; }
284 /* Always pass one offline event up the stack */
285 if(dev
->offline
> 0 && dev
->interrupt_in_buffer
[1] != 0xff) { dev
->offline
= 0; }
286 if(dev
->offline
== 0 && dev
->interrupt_in_buffer
[1] == 0xff) { dev
->offline
= 1; }
288 dbg_info(&dev
->intf
->dev
, "%s: head, tail are %x, %x\n", __FUNCTION__
,dev
->ring_head
,dev
->ring_tail
);
289 next_ring_head
= (dev
->ring_head
+1) % ring_buffer_size
;
291 if (next_ring_head
!= dev
->ring_tail
) {
292 memcpy(&((*dev
->ring_buffer
)[dev
->ring_head
]),
293 dev
->interrupt_in_buffer
, urb
->actual_length
);
294 dev
->ring_head
= next_ring_head
;
296 memset(dev
->interrupt_in_buffer
, 0, urb
->actual_length
);
298 dev_warn(&dev
->intf
->dev
,
299 "Ring buffer overflow, %d bytes dropped\n",
301 memset(dev
->interrupt_in_buffer
, 0, urb
->actual_length
);
306 /* resubmit if we're still running */
307 if (dev
->interrupt_in_running
&& dev
->intf
) {
308 retval
= usb_submit_urb(dev
->interrupt_in_urb
, GFP_ATOMIC
);
310 dev_err(&dev
->intf
->dev
,
311 "usb_submit_urb failed (%d)\n", retval
);
315 dev
->interrupt_in_done
= 1;
316 wake_up_interruptible(&dev
->read_wait
);
320 * usb_alphatrack_interrupt_out_callback
322 static void usb_alphatrack_interrupt_out_callback(struct urb
*urb
)
324 struct usb_alphatrack
*dev
= urb
->context
;
326 /* sync/async unlink faults aren't errors */
327 if (urb
->status
&& !(urb
->status
== -ENOENT
||
328 urb
->status
== -ECONNRESET
||
329 urb
->status
== -ESHUTDOWN
))
330 dbg_info(&dev
->intf
->dev
,
331 "%s - nonzero write interrupt status received: %d\n",
332 __FUNCTION__
, urb
->status
);
333 atomic_dec(&dev
->writes_pending
);
334 dev
->interrupt_out_busy
= 0;
335 wake_up_interruptible(&dev
->write_wait
);
339 * usb_alphatrack_open
341 static int usb_alphatrack_open(struct inode
*inode
, struct file
*file
)
343 struct usb_alphatrack
*dev
;
346 struct usb_interface
*interface
;
348 nonseekable_open(inode
, file
);
349 subminor
= iminor(inode
);
351 mutex_lock(&disconnect_mutex
);
353 interface
= usb_find_interface(&usb_alphatrack_driver
, subminor
);
356 err("%s - error, can't find device for minor %d\n",
357 __FUNCTION__
, subminor
);
359 goto unlock_disconnect_exit
;
362 dev
= usb_get_intfdata(interface
);
366 goto unlock_disconnect_exit
;
369 /* lock this device */
370 if (down_interruptible(&dev
->sem
)) {
371 retval
= -ERESTARTSYS
;
372 goto unlock_disconnect_exit
;
375 /* allow opening only once */
376 if (dev
->open_count
) {
382 /* initialize in direction */
385 usb_fill_int_urb(dev
->interrupt_in_urb
,
386 interface_to_usbdev(interface
),
387 usb_rcvintpipe(interface_to_usbdev(interface
),
388 dev
->interrupt_in_endpoint
->bEndpointAddress
),
389 dev
->interrupt_in_buffer
,
390 dev
->interrupt_in_endpoint_size
,
391 usb_alphatrack_interrupt_in_callback
,
393 dev
->interrupt_in_interval
);
395 dev
->interrupt_in_running
= 1;
396 dev
->interrupt_in_done
= 0;
400 retval
= usb_submit_urb(dev
->interrupt_in_urb
, GFP_KERNEL
);
402 dev_err(&interface
->dev
, "Couldn't submit interrupt_in_urb %d\n", retval
);
403 dev
->interrupt_in_running
= 0;
408 /* save device in the file's private structure */
409 file
->private_data
= dev
;
415 unlock_disconnect_exit
:
416 mutex_unlock(&disconnect_mutex
);
422 * usb_alphatrack_release
424 static int usb_alphatrack_release(struct inode
*inode
, struct file
*file
)
426 struct usb_alphatrack
*dev
;
429 dev
= file
->private_data
;
436 if (down_interruptible(&dev
->sem
)) {
437 retval
= -ERESTARTSYS
;
441 if (dev
->open_count
!= 1) {
446 if (dev
->intf
== NULL
) {
447 /* the device was unplugged before the file was released */
449 /* unlock here as usb_alphatrack_delete frees dev */
450 usb_alphatrack_delete(dev
);
455 /* wait until write transfer is finished */
456 if (dev
->interrupt_out_busy
)
457 wait_event_interruptible_timeout(dev
->write_wait
, !dev
->interrupt_out_busy
, 2 * HZ
);
458 usb_alphatrack_abort_transfers(dev
);
469 * usb_alphatrack_poll
471 static unsigned int usb_alphatrack_poll(struct file
*file
, poll_table
*wait
)
473 struct usb_alphatrack
*dev
;
474 unsigned int mask
= 0;
476 dev
= file
->private_data
;
478 poll_wait(file
, &dev
->read_wait
, wait
);
479 poll_wait(file
, &dev
->write_wait
, wait
);
481 if (dev
->ring_head
!= dev
->ring_tail
)
482 mask
|= POLLIN
| POLLRDNORM
;
483 if (!dev
->interrupt_out_busy
)
484 mask
|= POLLOUT
| POLLWRNORM
;
490 * usb_alphatrack_read
492 static ssize_t
usb_alphatrack_read(struct file
*file
, char __user
*buffer
, size_t count
,
495 struct usb_alphatrack
*dev
;
500 dev
= file
->private_data
;
502 /* verify that we actually have some data to read */
506 /* lock this object */
507 if (down_interruptible(&dev
->sem
)) {
508 retval
= -ERESTARTSYS
;
512 /* verify that the device wasn't unplugged */
513 if (dev
->intf
== NULL
) {
515 err("No device or device unplugged %d\n", retval
);
519 while (dev
->ring_head
== dev
->ring_tail
) {
520 if (file
->f_flags
& O_NONBLOCK
) {
524 dev
->interrupt_in_done
= 0 ;
525 retval
= wait_event_interruptible(dev
->read_wait
, dev
->interrupt_in_done
);
531 alphatrack_ocmd_info(&dev
->intf
->dev
, &(*dev
->ring_buffer
)[dev
->ring_tail
].cmd
, "%s", ": copying to userspace");
534 while((c
< count
) && (dev
->ring_tail
!= dev
->ring_head
)) {
535 if (copy_to_user(&buffer
[c
], &(*dev
->ring_buffer
)[dev
->ring_tail
], INPUT_CMD_SIZE
)) {
539 dev
->ring_tail
= (dev
->ring_tail
+1) % ring_buffer_size
;
541 dbg_info(&dev
->intf
->dev
, "%s: head, tail are %x, %x\n", __FUNCTION__
,dev
->ring_head
,dev
->ring_tail
);
546 /* unlock the device */
554 * usb_alphatrack_write
556 static ssize_t
usb_alphatrack_write(struct file
*file
, const char __user
*buffer
,
557 size_t count
, loff_t
*ppos
)
559 struct usb_alphatrack
*dev
;
560 size_t bytes_to_write
;
563 dev
= file
->private_data
;
565 /* verify that we actually have some data to write */
569 /* lock this object */
570 if (down_interruptible(&dev
->sem
)) {
571 retval
= -ERESTARTSYS
;
575 /* verify that the device wasn't unplugged */
576 if (dev
->intf
== NULL
) {
578 err("No device or device unplugged %d\n", retval
);
582 /* wait until previous transfer is finished */
583 if (dev
->interrupt_out_busy
) {
584 if (file
->f_flags
& O_NONBLOCK
) {
588 retval
= wait_event_interruptible(dev
->write_wait
, !dev
->interrupt_out_busy
);
594 /* write the data into interrupt_out_buffer from userspace */
595 /* FIXME - if you write more than 12 bytes this breaks */
596 bytes_to_write
= min(count
, write_buffer_size
*dev
->interrupt_out_endpoint_size
);
597 if (bytes_to_write
< count
)
598 dev_warn(&dev
->intf
->dev
, "Write buffer overflow, %zd bytes dropped\n",count
-bytes_to_write
);
600 dbg_info(&dev
->intf
->dev
, "%s: count = %zd, bytes_to_write = %zd\n", __FUNCTION__
, count
, bytes_to_write
);
602 if (copy_from_user(dev
->interrupt_out_buffer
, buffer
, bytes_to_write
)) {
607 if (dev
->interrupt_out_endpoint
== NULL
) {
608 err("Endpoint should not be be null! \n");
612 /* send off the urb */
613 usb_fill_int_urb(dev
->interrupt_out_urb
,
614 interface_to_usbdev(dev
->intf
),
615 usb_sndintpipe(interface_to_usbdev(dev
->intf
),
616 dev
->interrupt_out_endpoint
->bEndpointAddress
),
617 dev
->interrupt_out_buffer
,
619 usb_alphatrack_interrupt_out_callback
,
621 dev
->interrupt_out_interval
);
622 dev
->interrupt_out_busy
= 1;
623 atomic_inc(&dev
->writes_pending
);
626 retval
= usb_submit_urb(dev
->interrupt_out_urb
, GFP_KERNEL
);
628 dev
->interrupt_out_busy
= 0;
629 err("Couldn't submit interrupt_out_urb %d\n", retval
);
630 atomic_dec(&dev
->writes_pending
);
633 retval
= bytes_to_write
;
636 /* unlock the device */
643 /* file operations needed when we register this driver */
644 static const struct file_operations usb_alphatrack_fops
= {
645 .owner
= THIS_MODULE
,
646 .read
= usb_alphatrack_read
,
647 .write
= usb_alphatrack_write
,
648 .open
= usb_alphatrack_open
,
649 .release
= usb_alphatrack_release
,
650 .poll
= usb_alphatrack_poll
,
654 * usb class driver info in order to get a minor number from the usb core,
655 * and to have the device registered with the driver core
658 static struct usb_class_driver usb_alphatrack_class
= {
659 .name
= "alphatrack%d",
660 .fops
= &usb_alphatrack_fops
,
661 .minor_base
= USB_ALPHATRACK_MINOR_BASE
,
666 * usb_alphatrack_probe
668 * Called by the usb core when a new device is connected that it thinks
669 * this driver might be interested in.
671 static int usb_alphatrack_probe(struct usb_interface
*intf
, const struct usb_device_id
*id
)
673 struct usb_device
*udev
= interface_to_usbdev(intf
);
674 struct usb_alphatrack
*dev
= NULL
;
675 struct usb_host_interface
*iface_desc
;
676 struct usb_endpoint_descriptor
*endpoint
;
679 int retval
= -ENOMEM
;
681 /* allocate memory for our device state and intialize it */
683 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
685 dev_err(&intf
->dev
, "Out of memory\n");
688 init_MUTEX(&dev
->sem
);
690 init_waitqueue_head(&dev
->read_wait
);
691 init_waitqueue_head(&dev
->write_wait
);
693 iface_desc
= intf
->cur_altsetting
;
695 /* set up the endpoint information */
696 for (i
= 0; i
< iface_desc
->desc
.bNumEndpoints
; ++i
) {
697 endpoint
= &iface_desc
->endpoint
[i
].desc
;
699 if (usb_endpoint_is_int_in(endpoint
))
700 dev
->interrupt_in_endpoint
= endpoint
;
702 if (usb_endpoint_is_int_out(endpoint
))
703 dev
->interrupt_out_endpoint
= endpoint
;
705 if (dev
->interrupt_in_endpoint
== NULL
) {
706 dev_err(&intf
->dev
, "Interrupt in endpoint not found\n");
709 if (dev
->interrupt_out_endpoint
== NULL
)
710 dev_warn(&intf
->dev
, "Interrupt out endpoint not found (using control endpoint instead)\n");
712 dev
->interrupt_in_endpoint_size
= le16_to_cpu(dev
->interrupt_in_endpoint
->wMaxPacketSize
);
714 if (dev
->interrupt_in_endpoint_size
!= 64)
715 dev_warn(&intf
->dev
, "Interrupt in endpoint size is not 64!\n");
717 if(ring_buffer_size
== 0) { ring_buffer_size
= RING_BUFFER_SIZE
; }
719 true_size
= min(ring_buffer_size
,RING_BUFFER_SIZE
);
721 /* FIXME - there are more usb_alloc routines for dma correctness. Needed? */
723 // dev->ring_buffer = kmalloc((true_size*sizeof(struct alphatrack_icmd))+12, GFP_KERNEL);
724 dev
->ring_buffer
= kmalloc((true_size
*sizeof(struct alphatrack_icmd
)), GFP_KERNEL
);
726 if (!dev
->ring_buffer
) {
727 dev_err(&intf
->dev
, "Couldn't allocate input ring_buffer of size %d\n",true_size
);
731 dev
->interrupt_in_buffer
= kmalloc(dev
->interrupt_in_endpoint_size
, GFP_KERNEL
);
733 if (!dev
->interrupt_in_buffer
) {
734 dev_err(&intf
->dev
, "Couldn't allocate interrupt_in_buffer\n");
737 dev
->oldi_buffer
= kmalloc(dev
->interrupt_in_endpoint_size
, GFP_KERNEL
);
738 if (!dev
->oldi_buffer
) {
739 dev_err(&intf
->dev
, "Couldn't allocate old buffer\n");
742 dev
->interrupt_in_urb
= usb_alloc_urb(0, GFP_KERNEL
);
743 if (!dev
->interrupt_in_urb
) {
744 dev_err(&intf
->dev
, "Couldn't allocate interrupt_in_urb\n");
748 dev
->interrupt_out_endpoint_size
= dev
->interrupt_out_endpoint
? le16_to_cpu(dev
->interrupt_out_endpoint
->wMaxPacketSize
) :
749 udev
->descriptor
.bMaxPacketSize0
;
751 if (dev
->interrupt_out_endpoint_size
!=64)
752 dev_warn(&intf
->dev
, "Interrupt out endpoint size is not 64!)\n");
754 if(write_buffer_size
== 0) { write_buffer_size
= WRITE_BUFFER_SIZE
; }
755 true_size
= min(write_buffer_size
,WRITE_BUFFER_SIZE
);
757 dev
->interrupt_out_buffer
= kmalloc(true_size
*dev
->interrupt_out_endpoint_size
, GFP_KERNEL
);
759 if (!dev
->interrupt_out_buffer
) {
760 dev_err(&intf
->dev
, "Couldn't allocate interrupt_out_buffer\n");
764 dev
->write_buffer
= kmalloc(sizeof(struct alphatrack_ocmd
)*true_size
, GFP_KERNEL
);
766 if (!dev
->write_buffer
) {
767 dev_err(&intf
->dev
, "Couldn't allocate write_buffer \n");
771 dev
->interrupt_out_urb
= usb_alloc_urb(0, GFP_KERNEL
);
772 if (!dev
->interrupt_out_urb
) {
773 dev_err(&intf
->dev
, "Couldn't allocate interrupt_out_urb\n");
776 dev
->interrupt_in_interval
= min_interrupt_in_interval
> dev
->interrupt_in_endpoint
->bInterval
? min_interrupt_in_interval
: dev
->interrupt_in_endpoint
->bInterval
;
777 if (dev
->interrupt_out_endpoint
)
778 dev
->interrupt_out_interval
= min_interrupt_out_interval
> dev
->interrupt_out_endpoint
->bInterval
? min_interrupt_out_interval
: dev
->interrupt_out_endpoint
->bInterval
;
780 /* we can register the device now, as it is ready */
781 usb_set_intfdata(intf
, dev
);
783 atomic_set(&dev
->writes_pending
,0);
784 retval
= usb_register_dev(intf
, &usb_alphatrack_class
);
786 /* something prevented us from registering this driver */
787 dev_err(&intf
->dev
, "Not able to get a minor for this device.\n");
788 usb_set_intfdata(intf
, NULL
);
792 /* let the user know what node this device is now attached to */
793 dev_info(&intf
->dev
, "Alphatrack Device #%d now attached to major %d minor %d\n",
794 (intf
->minor
- USB_ALPHATRACK_MINOR_BASE
), USB_MAJOR
, intf
->minor
);
800 usb_alphatrack_delete(dev
);
806 * usb_alphatrack_disconnect
808 * Called by the usb core when the device is removed from the system.
810 static void usb_alphatrack_disconnect(struct usb_interface
*intf
)
812 struct usb_alphatrack
*dev
;
815 mutex_lock(&disconnect_mutex
);
817 dev
= usb_get_intfdata(intf
);
818 usb_set_intfdata(intf
, NULL
);
824 /* give back our minor */
825 usb_deregister_dev(intf
, &usb_alphatrack_class
);
827 /* if the device is not opened, then we clean up right now */
828 if (!dev
->open_count
) {
830 usb_alphatrack_delete(dev
);
836 atomic_set(&dev
->writes_pending
,0);
837 mutex_unlock(&disconnect_mutex
);
839 dev_info(&intf
->dev
, "Alphatrack Surface #%d now disconnected\n",
840 (minor
- USB_ALPHATRACK_MINOR_BASE
));
843 /* usb specific object needed to register this driver with the usb subsystem */
844 static struct usb_driver usb_alphatrack_driver
= {
845 .name
= "alphatrack",
846 .probe
= usb_alphatrack_probe
,
847 .disconnect
= usb_alphatrack_disconnect
,
848 .id_table
= usb_alphatrack_table
,
852 * usb_alphatrack_init
854 static int __init
usb_alphatrack_init(void)
858 /* register this driver with the USB subsystem */
859 retval
= usb_register(&usb_alphatrack_driver
);
861 err("usb_register failed for the "__FILE__
" driver. Error number %d\n", retval
);
867 * usb_alphatrack_exit
869 static void __exit
usb_alphatrack_exit(void)
871 /* deregister this driver with the USB subsystem */
872 usb_deregister(&usb_alphatrack_driver
);
875 module_init(usb_alphatrack_init
);
876 module_exit(usb_alphatrack_exit
);