2 * Apple USB BCM5974 (Macbook Air and Penryn Macbook Pro) multitouch driver
4 * Copyright (C) 2008 Henrik Rydberg (rydberg@euromail.se)
6 * The USB initialization and package decoding was made by
7 * Scott Shawcroft as part of the touchd user-space driver project:
8 * Copyright (C) 2008 Scott Shawcroft (scott.shawcroft@gmail.com)
10 * The BCM5974 driver is based on the appletouch driver:
11 * Copyright (C) 2001-2004 Greg Kroah-Hartman (greg@kroah.com)
12 * Copyright (C) 2005 Johannes Berg (johannes@sipsolutions.net)
13 * Copyright (C) 2005 Stelian Pop (stelian@popies.net)
14 * Copyright (C) 2005 Frank Arnold (frank@scirocco-5v-turbo.de)
15 * Copyright (C) 2005 Peter Osterlund (petero2@telia.com)
16 * Copyright (C) 2005 Michael Hanselmann (linux-kernel@hansmi.ch)
17 * Copyright (C) 2006 Nicolas Boichat (nicolas@boichat.ch)
19 * This program is free software; you can redistribute it and/or modify
20 * it under the terms of the GNU General Public License as published by
21 * the Free Software Foundation; either version 2 of the License, or
22 * (at your option) any later version.
24 * This program is distributed in the hope that it will be useful,
25 * but WITHOUT ANY WARRANTY; without even the implied warranty of
26 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
27 * GNU General Public License for more details.
29 * You should have received a copy of the GNU General Public License
30 * along with this program; if not, write to the Free Software
31 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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/usb/input.h>
41 #include <linux/hid.h>
42 #include <linux/mutex.h>
44 #define USB_VENDOR_ID_APPLE 0x05ac
46 /* MacbookAir, aka wellspring */
47 #define USB_DEVICE_ID_APPLE_WELLSPRING_ANSI 0x0223
48 #define USB_DEVICE_ID_APPLE_WELLSPRING_ISO 0x0224
49 #define USB_DEVICE_ID_APPLE_WELLSPRING_JIS 0x0225
50 /* MacbookProPenryn, aka wellspring2 */
51 #define USB_DEVICE_ID_APPLE_WELLSPRING2_ANSI 0x0230
52 #define USB_DEVICE_ID_APPLE_WELLSPRING2_ISO 0x0231
53 #define USB_DEVICE_ID_APPLE_WELLSPRING2_JIS 0x0232
55 #define BCM5974_DEVICE(prod) { \
56 .match_flags = (USB_DEVICE_ID_MATCH_DEVICE | \
57 USB_DEVICE_ID_MATCH_INT_CLASS | \
58 USB_DEVICE_ID_MATCH_INT_PROTOCOL), \
59 .idVendor = USB_VENDOR_ID_APPLE, \
60 .idProduct = (prod), \
61 .bInterfaceClass = USB_INTERFACE_CLASS_HID, \
62 .bInterfaceProtocol = USB_INTERFACE_PROTOCOL_MOUSE \
65 /* table of devices that work with this driver */
66 static const struct usb_device_id bcm5974_table[] = {
68 BCM5974_DEVICE(USB_DEVICE_ID_APPLE_WELLSPRING_ANSI),
69 BCM5974_DEVICE(USB_DEVICE_ID_APPLE_WELLSPRING_ISO),
70 BCM5974_DEVICE(USB_DEVICE_ID_APPLE_WELLSPRING_JIS),
71 /* MacbookProPenryn */
72 BCM5974_DEVICE(USB_DEVICE_ID_APPLE_WELLSPRING2_ANSI),
73 BCM5974_DEVICE(USB_DEVICE_ID_APPLE_WELLSPRING2_ISO),
74 BCM5974_DEVICE(USB_DEVICE_ID_APPLE_WELLSPRING2_JIS),
75 /* Terminating entry */
78 MODULE_DEVICE_TABLE(usb, bcm5974_table);
80 MODULE_AUTHOR("Henrik Rydberg");
81 MODULE_DESCRIPTION("Apple USB BCM5974 multitouch driver");
82 MODULE_LICENSE("GPL");
84 #define dprintk(level, format, a...)\
85 { if (debug >= level) printk(KERN_DEBUG format, ##a); }
88 module_param(debug, int, 0644);
89 MODULE_PARM_DESC(debug, "Activate debugging output");
91 /* button data structure */
93 u8 unknown1; /* constant */
94 u8 button; /* left button */
95 u8 rel_x; /* relative x coordinate */
96 u8 rel_y; /* relative y coordinate */
99 /* trackpad header structure */
101 u8 unknown1[16]; /* constants, timers, etc */
102 u8 fingers; /* number of fingers on trackpad */
103 u8 unknown2[9]; /* constants, timers, etc */
106 /* trackpad finger structure */
108 __le16 origin; /* zero when switching track finger */
109 __le16 abs_x; /* absolute x coodinate */
110 __le16 abs_y; /* absolute y coodinate */
111 __le16 rel_x; /* relative x coodinate */
112 __le16 rel_y; /* relative y coodinate */
113 __le16 size_major; /* finger size, major axis? */
114 __le16 size_minor; /* finger size, minor axis? */
115 __le16 orientation; /* 16384 when point, else 15 bit angle */
116 __le16 force_major; /* trackpad force, major axis? */
117 __le16 force_minor; /* trackpad force, minor axis? */
118 __le16 unused[3]; /* zeros */
119 __le16 multi; /* one finger: varies, more fingers: constant */
122 /* trackpad data structure, empirically at least ten fingers */
124 struct tp_header header;
125 struct tp_finger finger[16];
128 /* device-specific parameters */
129 struct bcm5974_param {
130 int dim; /* logical dimension */
131 int fuzz; /* logical noise value */
132 int devmin; /* device minimum reading */
133 int devmax; /* device maximum reading */
136 /* device-specific configuration */
137 struct bcm5974_config {
138 int ansi, iso, jis; /* the product id of this device */
139 int bt_ep; /* the endpoint of the button interface */
140 int bt_datalen; /* data length of the button interface */
141 int tp_ep; /* the endpoint of the trackpad interface */
142 int tp_datalen; /* data length of the trackpad interface */
143 struct bcm5974_param p; /* finger pressure limits */
144 struct bcm5974_param w; /* finger width limits */
145 struct bcm5974_param x; /* horizontal limits */
146 struct bcm5974_param y; /* vertical limits */
149 /* logical device structure */
152 struct usb_device *udev; /* usb device */
153 struct usb_interface *intf; /* our interface */
154 struct input_dev *input; /* input dev */
155 struct bcm5974_config cfg; /* device configuration */
156 struct mutex pm_mutex; /* serialize access to open/suspend */
157 int opened; /* 1: opened, 0: closed */
158 struct urb *bt_urb; /* button usb request block */
159 struct bt_data *bt_data; /* button transferred data */
160 struct urb *tp_urb; /* trackpad usb request block */
161 struct tp_data *tp_data; /* trackpad transferred data */
162 int fingers; /* number of fingers on trackpad */
165 /* logical dimensions */
166 #define DIM_PRESSURE 256 /* maximum finger pressure */
167 #define DIM_WIDTH 16 /* maximum finger width */
168 #define DIM_X 1280 /* maximum trackpad x value */
169 #define DIM_Y 800 /* maximum trackpad y value */
171 /* logical signal quality */
172 #define SN_PRESSURE 45 /* pressure signal-to-noise ratio */
173 #define SN_WIDTH 100 /* width signal-to-noise ratio */
174 #define SN_COORD 250 /* coordinate signal-to-noise ratio */
176 /* pressure thresholds */
177 #define PRESSURE_LOW (2 * DIM_PRESSURE / SN_PRESSURE)
178 #define PRESSURE_HIGH (3 * PRESSURE_LOW)
180 /* device constants */
181 static const struct bcm5974_config bcm5974_config_table[] = {
183 USB_DEVICE_ID_APPLE_WELLSPRING_ANSI,
184 USB_DEVICE_ID_APPLE_WELLSPRING_ISO,
185 USB_DEVICE_ID_APPLE_WELLSPRING_JIS,
186 0x84, sizeof(struct bt_data),
187 0x81, sizeof(struct tp_data),
188 { DIM_PRESSURE, DIM_PRESSURE / SN_PRESSURE, 0, 256 },
189 { DIM_WIDTH, DIM_WIDTH / SN_WIDTH, 0, 2048 },
190 { DIM_X, DIM_X / SN_COORD, -4824, 5342 },
191 { DIM_Y, DIM_Y / SN_COORD, -172, 5820 }
194 USB_DEVICE_ID_APPLE_WELLSPRING2_ANSI,
195 USB_DEVICE_ID_APPLE_WELLSPRING2_ISO,
196 USB_DEVICE_ID_APPLE_WELLSPRING2_JIS,
197 0x84, sizeof(struct bt_data),
198 0x81, sizeof(struct tp_data),
199 { DIM_PRESSURE, DIM_PRESSURE / SN_PRESSURE, 0, 256 },
200 { DIM_WIDTH, DIM_WIDTH / SN_WIDTH, 0, 2048 },
201 { DIM_X, DIM_X / SN_COORD, -4824, 4824 },
202 { DIM_Y, DIM_Y / SN_COORD, -172, 4290 }
207 /* return the device-specific configuration by device */
208 static const struct bcm5974_config *bcm5974_get_config(struct usb_device *udev)
210 u16 id = le16_to_cpu(udev->descriptor.idProduct);
211 const struct bcm5974_config *cfg;
213 for (cfg = bcm5974_config_table; cfg->ansi; ++cfg)
214 if (cfg->ansi == id || cfg->iso == id || cfg->jis == id)
217 return bcm5974_config_table;
220 /* convert 16-bit little endian to signed integer */
221 static inline int raw2int(__le16 x)
223 return (signed short)le16_to_cpu(x);
226 /* scale device data to logical dimensions (asserts devmin < devmax) */
227 static inline int int2scale(const struct bcm5974_param *p, int x)
229 return x * p->dim / (p->devmax - p->devmin);
232 /* all logical value ranges are [0,dim). */
233 static inline int int2bound(const struct bcm5974_param *p, int x)
235 int s = int2scale(p, x);
237 return clamp_val(s, 0, p->dim - 1);
240 /* setup which logical events to report */
241 static void setup_events_to_report(struct input_dev *input_dev,
242 const struct bcm5974_config *cfg)
244 __set_bit(EV_ABS, input_dev->evbit);
246 input_set_abs_params(input_dev, ABS_PRESSURE,
247 0, cfg->p.dim, cfg->p.fuzz, 0);
248 input_set_abs_params(input_dev, ABS_TOOL_WIDTH,
249 0, cfg->w.dim, cfg->w.fuzz, 0);
250 input_set_abs_params(input_dev, ABS_X,
251 0, cfg->x.dim, cfg->x.fuzz, 0);
252 input_set_abs_params(input_dev, ABS_Y,
253 0, cfg->y.dim, cfg->y.fuzz, 0);
255 __set_bit(EV_KEY, input_dev->evbit);
256 __set_bit(BTN_TOUCH, input_dev->keybit);
257 __set_bit(BTN_TOOL_FINGER, input_dev->keybit);
258 __set_bit(BTN_TOOL_DOUBLETAP, input_dev->keybit);
259 __set_bit(BTN_TOOL_TRIPLETAP, input_dev->keybit);
260 __set_bit(BTN_LEFT, input_dev->keybit);
263 /* report button data as logical button state */
264 static int report_bt_state(struct bcm5974 *dev, int size)
266 if (size != sizeof(struct bt_data))
269 input_report_key(dev->input, BTN_LEFT, dev->bt_data->button);
270 input_sync(dev->input);
275 /* report trackpad data as logical trackpad state */
276 static int report_tp_state(struct bcm5974 *dev, int size)
278 const struct bcm5974_config *c = &dev->cfg;
279 const struct tp_finger *f = dev->tp_data->finger;
280 struct input_dev *input = dev->input;
281 const int fingers = (size - 26) / 28;
282 int raw_p, raw_w, raw_x, raw_y;
283 int ptest = 0, origin = 0, nmin = 0, nmax = 0;
284 int abs_p = 0, abs_w = 0, abs_x = 0, abs_y = 0;
286 if (size < 26 || (size - 26) % 28 != 0)
289 /* always track the first finger; when detached, start over */
291 raw_p = raw2int(f->force_major);
292 raw_w = raw2int(f->size_major);
293 raw_x = raw2int(f->abs_x);
294 raw_y = raw2int(f->abs_y);
297 "bcm5974: raw: p: %+05d w: %+05d x: %+05d y: %+05d\n",
298 raw_p, raw_w, raw_x, raw_y);
300 ptest = int2bound(&c->p, raw_p);
301 origin = raw2int(f->origin);
304 /* while tracking finger still valid, count all fingers */
305 if (ptest > PRESSURE_LOW && origin) {
307 abs_w = int2bound(&c->w, raw_w);
308 abs_x = int2bound(&c->x, raw_x - c->x.devmin);
309 abs_y = int2bound(&c->y, c->y.devmax - raw_y);
310 for (; f != dev->tp_data->finger + fingers; f++) {
311 ptest = int2bound(&c->p, raw2int(f->force_major));
312 if (ptest > PRESSURE_LOW)
314 if (ptest > PRESSURE_HIGH)
319 if (dev->fingers < nmin)
321 if (dev->fingers > nmax)
324 input_report_key(input, BTN_TOUCH, dev->fingers > 0);
325 input_report_key(input, BTN_TOOL_FINGER, dev->fingers == 1);
326 input_report_key(input, BTN_TOOL_DOUBLETAP, dev->fingers == 2);
327 input_report_key(input, BTN_TOOL_TRIPLETAP, dev->fingers > 2);
329 input_report_abs(input, ABS_PRESSURE, abs_p);
330 input_report_abs(input, ABS_TOOL_WIDTH, abs_w);
333 input_report_abs(input, ABS_X, abs_x);
334 input_report_abs(input, ABS_Y, abs_y);
337 "bcm5974: abs: p: %+05d w: %+05d x: %+05d y: %+05d "
338 "nmin: %d nmax: %d n: %d\n",
339 abs_p, abs_w, abs_x, abs_y, nmin, nmax, dev->fingers);
348 /* Wellspring initialization constants */
349 #define BCM5974_WELLSPRING_MODE_READ_REQUEST_ID 1
350 #define BCM5974_WELLSPRING_MODE_WRITE_REQUEST_ID 9
351 #define BCM5974_WELLSPRING_MODE_REQUEST_VALUE 0x300
352 #define BCM5974_WELLSPRING_MODE_REQUEST_INDEX 0
353 #define BCM5974_WELLSPRING_MODE_VENDOR_VALUE 0x01
354 #define BCM5974_WELLSPRING_MODE_NORMAL_VALUE 0x08
356 static int bcm5974_wellspring_mode(struct bcm5974 *dev, bool on)
358 char *data = kmalloc(8, GFP_KERNEL);
359 int retval = 0, size;
362 err("bcm5974: out of memory");
367 /* read configuration */
368 size = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0),
369 BCM5974_WELLSPRING_MODE_READ_REQUEST_ID,
370 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
371 BCM5974_WELLSPRING_MODE_REQUEST_VALUE,
372 BCM5974_WELLSPRING_MODE_REQUEST_INDEX, data, 8, 5000);
375 err("bcm5974: could not read from device");
380 /* apply the mode switch */
382 BCM5974_WELLSPRING_MODE_VENDOR_VALUE :
383 BCM5974_WELLSPRING_MODE_NORMAL_VALUE;
385 /* write configuration */
386 size = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
387 BCM5974_WELLSPRING_MODE_WRITE_REQUEST_ID,
388 USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
389 BCM5974_WELLSPRING_MODE_REQUEST_VALUE,
390 BCM5974_WELLSPRING_MODE_REQUEST_INDEX, data, 8, 5000);
393 err("bcm5974: could not write to device");
398 dprintk(2, "bcm5974: switched to %s mode.\n",
399 on ? "wellspring" : "normal");
406 static void bcm5974_irq_button(struct urb *urb)
408 struct bcm5974 *dev = urb->context;
411 switch (urb->status) {
418 dbg("bcm5974: button urb shutting down: %d", urb->status);
421 dbg("bcm5974: button urb status: %d", urb->status);
425 if (report_bt_state(dev, dev->bt_urb->actual_length))
426 dprintk(1, "bcm5974: bad button package, length: %d\n",
427 dev->bt_urb->actual_length);
430 error = usb_submit_urb(dev->bt_urb, GFP_ATOMIC);
432 err("bcm5974: button urb failed: %d", error);
435 static void bcm5974_irq_trackpad(struct urb *urb)
437 struct bcm5974 *dev = urb->context;
440 switch (urb->status) {
447 dbg("bcm5974: trackpad urb shutting down: %d", urb->status);
450 dbg("bcm5974: trackpad urb status: %d", urb->status);
454 /* control response ignored */
455 if (dev->tp_urb->actual_length == 2)
458 if (report_tp_state(dev, dev->tp_urb->actual_length))
459 dprintk(1, "bcm5974: bad trackpad package, length: %d\n",
460 dev->tp_urb->actual_length);
463 error = usb_submit_urb(dev->tp_urb, GFP_ATOMIC);
465 err("bcm5974: trackpad urb failed: %d", error);
469 * The Wellspring trackpad, like many recent Apple trackpads, share
470 * the usb device with the keyboard. Since keyboards are usually
471 * handled by the HID system, the device ends up being handled by two
472 * modules. Setting up the device therefore becomes slightly
473 * complicated. To enable multitouch features, a mode switch is
474 * required, which is usually applied via the control interface of the
475 * device. It can be argued where this switch should take place. In
476 * some drivers, like appletouch, the switch is made during
477 * probe. However, the hid module may also alter the state of the
478 * device, resulting in trackpad malfunction under certain
479 * circumstances. To get around this problem, there is at least one
480 * example that utilizes the USB_QUIRK_RESET_RESUME quirk in order to
481 * recieve a reset_resume request rather than the normal resume.
482 * Since the implementation of reset_resume is equal to mode switch
483 * plus start_traffic, it seems easier to always do the switch when
484 * starting traffic on the device.
486 static int bcm5974_start_traffic(struct bcm5974 *dev)
488 if (bcm5974_wellspring_mode(dev, true)) {
489 dprintk(1, "bcm5974: mode switch failed\n");
493 if (usb_submit_urb(dev->bt_urb, GFP_KERNEL))
496 if (usb_submit_urb(dev->tp_urb, GFP_KERNEL))
502 usb_kill_urb(dev->bt_urb);
507 static void bcm5974_pause_traffic(struct bcm5974 *dev)
509 usb_kill_urb(dev->tp_urb);
510 usb_kill_urb(dev->bt_urb);
511 bcm5974_wellspring_mode(dev, false);
515 * The code below implements open/close and manual suspend/resume.
516 * All functions may be called in random order.
518 * Opening a suspended device fails with EACCES - permission denied.
520 * Failing a resume leaves the device resumed but closed.
522 static int bcm5974_open(struct input_dev *input)
524 struct bcm5974 *dev = input_get_drvdata(input);
527 error = usb_autopm_get_interface(dev->intf);
531 mutex_lock(&dev->pm_mutex);
533 error = bcm5974_start_traffic(dev);
537 mutex_unlock(&dev->pm_mutex);
540 usb_autopm_put_interface(dev->intf);
545 static void bcm5974_close(struct input_dev *input)
547 struct bcm5974 *dev = input_get_drvdata(input);
549 mutex_lock(&dev->pm_mutex);
551 bcm5974_pause_traffic(dev);
554 mutex_unlock(&dev->pm_mutex);
556 usb_autopm_put_interface(dev->intf);
559 static int bcm5974_suspend(struct usb_interface *iface, pm_message_t message)
561 struct bcm5974 *dev = usb_get_intfdata(iface);
563 mutex_lock(&dev->pm_mutex);
566 bcm5974_pause_traffic(dev);
568 mutex_unlock(&dev->pm_mutex);
573 static int bcm5974_resume(struct usb_interface *iface)
575 struct bcm5974 *dev = usb_get_intfdata(iface);
578 mutex_lock(&dev->pm_mutex);
581 error = bcm5974_start_traffic(dev);
583 mutex_unlock(&dev->pm_mutex);
588 static int bcm5974_probe(struct usb_interface *iface,
589 const struct usb_device_id *id)
591 struct usb_device *udev = interface_to_usbdev(iface);
592 const struct bcm5974_config *cfg;
594 struct input_dev *input_dev;
597 /* find the product index */
598 cfg = bcm5974_get_config(udev);
600 /* allocate memory for our device state and initialize it */
601 dev = kzalloc(sizeof(struct bcm5974), GFP_KERNEL);
602 input_dev = input_allocate_device();
603 if (!dev || !input_dev) {
604 err("bcm5974: out of memory");
610 dev->input = input_dev;
612 mutex_init(&dev->pm_mutex);
615 dev->bt_urb = usb_alloc_urb(0, GFP_KERNEL);
619 dev->tp_urb = usb_alloc_urb(0, GFP_KERNEL);
621 goto err_free_bt_urb;
623 dev->bt_data = usb_buffer_alloc(dev->udev,
624 dev->cfg.bt_datalen, GFP_KERNEL,
625 &dev->bt_urb->transfer_dma);
629 dev->tp_data = usb_buffer_alloc(dev->udev,
630 dev->cfg.tp_datalen, GFP_KERNEL,
631 &dev->tp_urb->transfer_dma);
633 goto err_free_bt_buffer;
635 usb_fill_int_urb(dev->bt_urb, udev,
636 usb_rcvintpipe(udev, cfg->bt_ep),
637 dev->bt_data, dev->cfg.bt_datalen,
638 bcm5974_irq_button, dev, 1);
640 usb_fill_int_urb(dev->tp_urb, udev,
641 usb_rcvintpipe(udev, cfg->tp_ep),
642 dev->tp_data, dev->cfg.tp_datalen,
643 bcm5974_irq_trackpad, dev, 1);
645 /* create bcm5974 device */
646 usb_make_path(udev, dev->phys, sizeof(dev->phys));
647 strlcat(dev->phys, "/input0", sizeof(dev->phys));
649 input_dev->name = "bcm5974";
650 input_dev->phys = dev->phys;
651 usb_to_input_id(dev->udev, &input_dev->id);
652 input_dev->dev.parent = &iface->dev;
654 input_set_drvdata(input_dev, dev);
656 input_dev->open = bcm5974_open;
657 input_dev->close = bcm5974_close;
659 setup_events_to_report(input_dev, cfg);
661 error = input_register_device(dev->input);
663 goto err_free_buffer;
665 /* save our data pointer in this interface device */
666 usb_set_intfdata(iface, dev);
671 usb_buffer_free(dev->udev, dev->cfg.tp_datalen,
672 dev->tp_data, dev->tp_urb->transfer_dma);
674 usb_buffer_free(dev->udev, dev->cfg.bt_datalen,
675 dev->bt_data, dev->bt_urb->transfer_dma);
677 usb_free_urb(dev->tp_urb);
679 usb_free_urb(dev->bt_urb);
681 usb_set_intfdata(iface, NULL);
682 input_free_device(input_dev);
687 static void bcm5974_disconnect(struct usb_interface *iface)
689 struct bcm5974 *dev = usb_get_intfdata(iface);
691 usb_set_intfdata(iface, NULL);
693 input_unregister_device(dev->input);
694 usb_buffer_free(dev->udev, dev->cfg.tp_datalen,
695 dev->tp_data, dev->tp_urb->transfer_dma);
696 usb_buffer_free(dev->udev, dev->cfg.bt_datalen,
697 dev->bt_data, dev->bt_urb->transfer_dma);
698 usb_free_urb(dev->tp_urb);
699 usb_free_urb(dev->bt_urb);
703 static struct usb_driver bcm5974_driver = {
705 .probe = bcm5974_probe,
706 .disconnect = bcm5974_disconnect,
707 .suspend = bcm5974_suspend,
708 .resume = bcm5974_resume,
709 .reset_resume = bcm5974_resume,
710 .id_table = bcm5974_table,
711 .supports_autosuspend = 1,
714 static int __init bcm5974_init(void)
716 return usb_register(&bcm5974_driver);
719 static void __exit bcm5974_exit(void)
721 usb_deregister(&bcm5974_driver);
724 module_init(bcm5974_init);
725 module_exit(bcm5974_exit);