xref: /freebsd/sys/dev/usb/input/atp.c (revision 0fcefb433d1265c4e6d4275eae7478cda1bf6a34)
1 /*-
2  * Copyright (c) 2014 Rohit Grover
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 /*
28  * Some tables, structures, definitions and constant values for the
29  * touchpad protocol has been copied from Linux's
30  * "drivers/input/mouse/bcm5974.c" which has the following copyright
31  * holders under GPLv2. All device specific code in this driver has
32  * been written from scratch. The decoding algorithm is based on
33  * output from FreeBSD's usbdump.
34  *
35  * Copyright (C) 2008      Henrik Rydberg (rydberg@euromail.se)
36  * Copyright (C) 2008      Scott Shawcroft (scott.shawcroft@gmail.com)
37  * Copyright (C) 2001-2004 Greg Kroah-Hartman (greg@kroah.com)
38  * Copyright (C) 2005      Johannes Berg (johannes@sipsolutions.net)
39  * Copyright (C) 2005      Stelian Pop (stelian@popies.net)
40  * Copyright (C) 2005      Frank Arnold (frank@scirocco-5v-turbo.de)
41  * Copyright (C) 2005      Peter Osterlund (petero2@telia.com)
42  * Copyright (C) 2005      Michael Hanselmann (linux-kernel@hansmi.ch)
43  * Copyright (C) 2006      Nicolas Boichat (nicolas@boichat.ch)
44  */
45 
46 /*
47  * Author's note: 'atp' supports two distinct families of Apple trackpad
48  * products: the older Fountain/Geyser and the latest Wellspring trackpads.
49  * The first version made its appearance with FreeBSD 8 and worked only with
50  * the Fountain/Geyser hardware. A fork of this driver for Wellspring was
51  * contributed by Huang Wen Hui. This driver unifies the Wellspring effort
52  * and also improves upon the original work.
53  *
54  * I'm grateful to Stephan Scheunig, Angela Naegele, and Nokia IT-support
55  * for helping me with access to hardware. Thanks also go to Nokia for
56  * giving me an opportunity to do this work.
57  */
58 
59 #include <sys/cdefs.h>
60 __FBSDID("$FreeBSD$");
61 
62 #include <sys/stdint.h>
63 #include <sys/stddef.h>
64 #include <sys/param.h>
65 #include <sys/types.h>
66 #include <sys/systm.h>
67 #include <sys/kernel.h>
68 #include <sys/bus.h>
69 #include <sys/module.h>
70 #include <sys/lock.h>
71 #include <sys/mutex.h>
72 #include <sys/sysctl.h>
73 #include <sys/malloc.h>
74 #include <sys/conf.h>
75 #include <sys/fcntl.h>
76 #include <sys/file.h>
77 #include <sys/selinfo.h>
78 #include <sys/poll.h>
79 
80 #include <dev/usb/usb.h>
81 #include <dev/usb/usbdi.h>
82 #include <dev/usb/usbdi_util.h>
83 #include <dev/usb/usbhid.h>
84 
85 #include "usbdevs.h"
86 
87 #define USB_DEBUG_VAR atp_debug
88 #include <dev/usb/usb_debug.h>
89 
90 #include <sys/mouse.h>
91 
92 #define ATP_DRIVER_NAME "atp"
93 
94 /*
95  * Driver specific options: the following options may be set by
96  * `options' statements in the kernel configuration file.
97  */
98 
99 /* The divisor used to translate sensor reported positions to mickeys. */
100 #ifndef ATP_SCALE_FACTOR
101 #define ATP_SCALE_FACTOR                  16
102 #endif
103 
104 /* Threshold for small movement noise (in mickeys) */
105 #ifndef ATP_SMALL_MOVEMENT_THRESHOLD
106 #define ATP_SMALL_MOVEMENT_THRESHOLD      30
107 #endif
108 
109 /* Threshold of instantaneous deltas beyond which movement is considered fast.*/
110 #ifndef ATP_FAST_MOVEMENT_TRESHOLD
111 #define ATP_FAST_MOVEMENT_TRESHOLD        150
112 #endif
113 
114 /*
115  * This is the age in microseconds beyond which a touch is considered
116  * to be a slide; and therefore a tap event isn't registered.
117  */
118 #ifndef ATP_TOUCH_TIMEOUT
119 #define ATP_TOUCH_TIMEOUT                 125000
120 #endif
121 
122 #ifndef ATP_IDLENESS_THRESHOLD
123 #define	ATP_IDLENESS_THRESHOLD 10
124 #endif
125 
126 #ifndef FG_SENSOR_NOISE_THRESHOLD
127 #define FG_SENSOR_NOISE_THRESHOLD 2
128 #endif
129 
130 /*
131  * A double-tap followed by a single-finger slide is treated as a
132  * special gesture. The driver responds to this gesture by assuming a
133  * virtual button-press for the lifetime of the slide. The following
134  * threshold is the maximum time gap (in microseconds) between the two
135  * tap events preceding the slide for such a gesture.
136  */
137 #ifndef ATP_DOUBLE_TAP_N_DRAG_THRESHOLD
138 #define ATP_DOUBLE_TAP_N_DRAG_THRESHOLD   200000
139 #endif
140 
141 /*
142  * The wait duration in ticks after losing a touch contact before
143  * zombied strokes are reaped and turned into button events.
144  */
145 #define ATP_ZOMBIE_STROKE_REAP_INTERVAL   (hz / 20)	/* 50 ms */
146 
147 /* The multiplier used to translate sensor reported positions to mickeys. */
148 #define FG_SCALE_FACTOR                   380
149 
150 /*
151  * The movement threshold for a stroke; this is the maximum difference
152  * in position which will be resolved as a continuation of a stroke
153  * component.
154  */
155 #define FG_MAX_DELTA_MICKEYS             ((3 * (FG_SCALE_FACTOR)) >> 1)
156 
157 /* Distance-squared threshold for matching a finger with a known stroke */
158 #ifndef WSP_MAX_ALLOWED_MATCH_DISTANCE_SQ
159 #define WSP_MAX_ALLOWED_MATCH_DISTANCE_SQ 1000000
160 #endif
161 
162 /* Ignore pressure spans with cumulative press. below this value. */
163 #define FG_PSPAN_MIN_CUM_PRESSURE         10
164 
165 /* Maximum allowed width for pressure-spans.*/
166 #define FG_PSPAN_MAX_WIDTH                4
167 
168 /* end of driver specific options */
169 
170 /* Tunables */
171 static SYSCTL_NODE(_hw_usb, OID_AUTO, atp, CTLFLAG_RW, 0, "USB ATP");
172 
173 #ifdef USB_DEBUG
174 enum atp_log_level {
175 	ATP_LLEVEL_DISABLED = 0,
176 	ATP_LLEVEL_ERROR,
177 	ATP_LLEVEL_DEBUG,       /* for troubleshooting */
178 	ATP_LLEVEL_INFO,        /* for diagnostics */
179 };
180 static int atp_debug = ATP_LLEVEL_ERROR; /* the default is to only log errors */
181 SYSCTL_INT(_hw_usb_atp, OID_AUTO, debug, CTLFLAG_RW,
182     &atp_debug, ATP_LLEVEL_ERROR, "ATP debug level");
183 #endif /* USB_DEBUG */
184 
185 static u_int atp_touch_timeout = ATP_TOUCH_TIMEOUT;
186 SYSCTL_UINT(_hw_usb_atp, OID_AUTO, touch_timeout, CTLFLAG_RW,
187     &atp_touch_timeout, 125000, "age threshold in microseconds for a touch");
188 
189 static u_int atp_double_tap_threshold = ATP_DOUBLE_TAP_N_DRAG_THRESHOLD;
190 SYSCTL_UINT(_hw_usb_atp, OID_AUTO, double_tap_threshold, CTLFLAG_RW,
191     &atp_double_tap_threshold, ATP_DOUBLE_TAP_N_DRAG_THRESHOLD,
192     "maximum time in microseconds to allow association between a double-tap and "
193     "drag gesture");
194 
195 static u_int atp_mickeys_scale_factor = ATP_SCALE_FACTOR;
196 static int atp_sysctl_scale_factor_handler(SYSCTL_HANDLER_ARGS);
197 SYSCTL_PROC(_hw_usb_atp, OID_AUTO, scale_factor, CTLTYPE_UINT | CTLFLAG_RW,
198     &atp_mickeys_scale_factor, sizeof(atp_mickeys_scale_factor),
199     atp_sysctl_scale_factor_handler, "IU", "movement scale factor");
200 
201 static u_int atp_small_movement_threshold = ATP_SMALL_MOVEMENT_THRESHOLD;
202 SYSCTL_UINT(_hw_usb_atp, OID_AUTO, small_movement, CTLFLAG_RW,
203     &atp_small_movement_threshold, ATP_SMALL_MOVEMENT_THRESHOLD,
204     "the small movement black-hole for filtering noise");
205 
206 static u_int atp_tap_minimum = 1;
207 SYSCTL_UINT(_hw_usb_atp, OID_AUTO, tap_minimum, CTLFLAG_RW,
208     &atp_tap_minimum, 1, "Minimum number of taps before detection");
209 
210 /*
211  * Strokes which accumulate at least this amount of absolute movement
212  * from the aggregate of their components are considered as
213  * slides. Unit: mickeys.
214  */
215 static u_int atp_slide_min_movement = 2 * ATP_SMALL_MOVEMENT_THRESHOLD;
216 SYSCTL_UINT(_hw_usb_atp, OID_AUTO, slide_min_movement, CTLFLAG_RW,
217     &atp_slide_min_movement, 2 * ATP_SMALL_MOVEMENT_THRESHOLD,
218     "strokes with at least this amt. of movement are considered slides");
219 
220 /*
221  * The minimum age of a stroke for it to be considered mature; this
222  * helps filter movements (noise) from immature strokes. Units: interrupts.
223  */
224 static u_int atp_stroke_maturity_threshold = 4;
225 SYSCTL_UINT(_hw_usb_atp, OID_AUTO, stroke_maturity_threshold, CTLFLAG_RW,
226     &atp_stroke_maturity_threshold, 4,
227     "the minimum age of a stroke for it to be considered mature");
228 
229 typedef enum atp_trackpad_family {
230 	TRACKPAD_FAMILY_FOUNTAIN_GEYSER,
231 	TRACKPAD_FAMILY_WELLSPRING,
232 	TRACKPAD_FAMILY_MAX /* keep this at the tail end of the enumeration */
233 } trackpad_family_t;
234 
235 enum fountain_geyser_product {
236 	FOUNTAIN,
237 	GEYSER1,
238 	GEYSER1_17inch,
239 	GEYSER2,
240 	GEYSER3,
241 	GEYSER4,
242 	FOUNTAIN_GEYSER_PRODUCT_MAX /* keep this at the end */
243 };
244 
245 enum wellspring_product {
246 	WELLSPRING1,
247 	WELLSPRING2,
248 	WELLSPRING3,
249 	WELLSPRING4,
250 	WELLSPRING4A,
251 	WELLSPRING5,
252 	WELLSPRING6A,
253 	WELLSPRING6,
254 	WELLSPRING5A,
255 	WELLSPRING7,
256 	WELLSPRING7A,
257 	WELLSPRING8,
258 	WELLSPRING_PRODUCT_MAX /* keep this at the end of the enumeration */
259 };
260 
261 /* trackpad header types */
262 enum fountain_geyser_trackpad_type {
263 	FG_TRACKPAD_TYPE_GEYSER1,
264 	FG_TRACKPAD_TYPE_GEYSER2,
265 	FG_TRACKPAD_TYPE_GEYSER3,
266 	FG_TRACKPAD_TYPE_GEYSER4,
267 };
268 enum wellspring_trackpad_type {
269 	WSP_TRACKPAD_TYPE1,      /* plain trackpad */
270 	WSP_TRACKPAD_TYPE2,      /* button integrated in trackpad */
271 	WSP_TRACKPAD_TYPE3       /* additional header fields since June 2013 */
272 };
273 
274 /*
275  * Trackpad family and product and family are encoded together in the
276  * driver_info value associated with a trackpad product.
277  */
278 #define N_PROD_BITS 8  /* Number of bits used to encode product */
279 #define ENCODE_DRIVER_INFO(FAMILY, PROD)      \
280     (((FAMILY) << N_PROD_BITS) | (PROD))
281 #define DECODE_FAMILY_FROM_DRIVER_INFO(INFO)  ((INFO) >> N_PROD_BITS)
282 #define DECODE_PRODUCT_FROM_DRIVER_INFO(INFO) \
283     ((INFO) & ((1 << N_PROD_BITS) - 1))
284 
285 #define FG_DRIVER_INFO(PRODUCT)               \
286     ENCODE_DRIVER_INFO(TRACKPAD_FAMILY_FOUNTAIN_GEYSER, PRODUCT)
287 #define WELLSPRING_DRIVER_INFO(PRODUCT)       \
288     ENCODE_DRIVER_INFO(TRACKPAD_FAMILY_WELLSPRING, PRODUCT)
289 
290 /*
291  * The following structure captures the state of a pressure span along
292  * an axis. Each contact with the touchpad results in separate
293  * pressure spans along the two axes.
294  */
295 typedef struct fg_pspan {
296 	u_int width;       /* in units of sensors */
297 	u_int cum;         /* cumulative compression (from all sensors) */
298 	u_int cog;         /* center of gravity */
299 	u_int loc;         /* location (scaled using the mickeys factor) */
300 	boolean_t matched; /* to track pspans as they match against strokes. */
301 } fg_pspan;
302 
303 #define FG_MAX_PSPANS_PER_AXIS 3
304 #define FG_MAX_STROKES         (2 * FG_MAX_PSPANS_PER_AXIS)
305 
306 #define WELLSPRING_INTERFACE_INDEX 1
307 
308 /* trackpad finger data offsets, le16-aligned */
309 #define WSP_TYPE1_FINGER_DATA_OFFSET  (13 * 2)
310 #define WSP_TYPE2_FINGER_DATA_OFFSET  (15 * 2)
311 #define WSP_TYPE3_FINGER_DATA_OFFSET  (19 * 2)
312 
313 /* trackpad button data offsets */
314 #define WSP_TYPE2_BUTTON_DATA_OFFSET   15
315 #define WSP_TYPE3_BUTTON_DATA_OFFSET   23
316 
317 /* list of device capability bits */
318 #define HAS_INTEGRATED_BUTTON   1
319 
320 /* trackpad finger structure - little endian */
321 struct wsp_finger_sensor_data {
322 	int16_t origin;       /* zero when switching track finger */
323 	int16_t abs_x;        /* absolute x coordinate */
324 	int16_t abs_y;        /* absolute y coordinate */
325 	int16_t rel_x;        /* relative x coordinate */
326 	int16_t rel_y;        /* relative y coordinate */
327 	int16_t tool_major;   /* tool area, major axis */
328 	int16_t tool_minor;   /* tool area, minor axis */
329 	int16_t orientation;  /* 16384 when point, else 15 bit angle */
330 	int16_t touch_major;  /* touch area, major axis */
331 	int16_t touch_minor;  /* touch area, minor axis */
332 	int16_t unused[3];    /* zeros */
333 	int16_t multi;        /* one finger: varies, more fingers: constant */
334 } __packed;
335 
336 typedef struct wsp_finger {
337 	/* to track fingers as they match against strokes. */
338 	boolean_t matched;
339 
340 	/* location (scaled using the mickeys factor) */
341 	int x;
342 	int y;
343 } wsp_finger_t;
344 
345 #define WSP_MAX_FINGERS               16
346 #define WSP_SIZEOF_FINGER_SENSOR_DATA sizeof(struct wsp_finger_sensor_data)
347 #define WSP_SIZEOF_ALL_FINGER_DATA    (WSP_MAX_FINGERS * \
348 				       WSP_SIZEOF_FINGER_SENSOR_DATA)
349 #define WSP_MAX_FINGER_ORIENTATION    16384
350 
351 #define ATP_SENSOR_DATA_BUF_MAX       1024
352 #if (ATP_SENSOR_DATA_BUF_MAX < ((WSP_MAX_FINGERS * 14 * 2) + \
353 				WSP_TYPE3_FINGER_DATA_OFFSET))
354 /* note: 14 * 2 in the above is based on sizeof(struct wsp_finger_sensor_data)*/
355 #error "ATP_SENSOR_DATA_BUF_MAX is too small"
356 #endif
357 
358 #define ATP_MAX_STROKES               MAX(WSP_MAX_FINGERS, FG_MAX_STROKES)
359 
360 #define FG_MAX_XSENSORS 26
361 #define FG_MAX_YSENSORS 16
362 
363 /* device-specific configuration */
364 struct fg_dev_params {
365 	u_int                              data_len;   /* for sensor data */
366 	u_int                              n_xsensors;
367 	u_int                              n_ysensors;
368 	enum fountain_geyser_trackpad_type prot;
369 };
370 struct wsp_dev_params {
371 	uint8_t  caps;               /* device capability bitmask */
372 	uint8_t  tp_type;            /* type of trackpad interface */
373 	uint8_t  finger_data_offset; /* offset to trackpad finger data */
374 };
375 
376 static const struct fg_dev_params fg_dev_params[FOUNTAIN_GEYSER_PRODUCT_MAX] = {
377 	[FOUNTAIN] = {
378 		.data_len   = 81,
379 		.n_xsensors = 16,
380 		.n_ysensors = 16,
381 		.prot       = FG_TRACKPAD_TYPE_GEYSER1
382 	},
383 	[GEYSER1] = {
384 		.data_len   = 81,
385 		.n_xsensors = 16,
386 		.n_ysensors = 16,
387 		.prot       = FG_TRACKPAD_TYPE_GEYSER1
388 	},
389 	[GEYSER1_17inch] = {
390 		.data_len   = 81,
391 		.n_xsensors = 26,
392 		.n_ysensors = 16,
393 		.prot       = FG_TRACKPAD_TYPE_GEYSER1
394 	},
395 	[GEYSER2] = {
396 		.data_len   = 64,
397 		.n_xsensors = 15,
398 		.n_ysensors = 9,
399 		.prot       = FG_TRACKPAD_TYPE_GEYSER2
400 	},
401 	[GEYSER3] = {
402 		.data_len   = 64,
403 		.n_xsensors = 20,
404 		.n_ysensors = 10,
405 		.prot       = FG_TRACKPAD_TYPE_GEYSER3
406 	},
407 	[GEYSER4] = {
408 		.data_len   = 64,
409 		.n_xsensors = 20,
410 		.n_ysensors = 10,
411 		.prot       = FG_TRACKPAD_TYPE_GEYSER4
412 	}
413 };
414 
415 static const STRUCT_USB_HOST_ID fg_devs[] = {
416 	/* PowerBooks Feb 2005, iBooks G4 */
417 	{ USB_VPI(USB_VENDOR_APPLE, 0x020e, FG_DRIVER_INFO(FOUNTAIN)) },
418 	{ USB_VPI(USB_VENDOR_APPLE, 0x020f, FG_DRIVER_INFO(FOUNTAIN)) },
419 	{ USB_VPI(USB_VENDOR_APPLE, 0x0210, FG_DRIVER_INFO(FOUNTAIN)) },
420 	{ USB_VPI(USB_VENDOR_APPLE, 0x030a, FG_DRIVER_INFO(FOUNTAIN)) },
421 	{ USB_VPI(USB_VENDOR_APPLE, 0x030b, FG_DRIVER_INFO(GEYSER1)) },
422 
423 	/* PowerBooks Oct 2005 */
424 	{ USB_VPI(USB_VENDOR_APPLE, 0x0214, FG_DRIVER_INFO(GEYSER2)) },
425 	{ USB_VPI(USB_VENDOR_APPLE, 0x0215, FG_DRIVER_INFO(GEYSER2)) },
426 	{ USB_VPI(USB_VENDOR_APPLE, 0x0216, FG_DRIVER_INFO(GEYSER2)) },
427 
428 	/* Core Duo MacBook & MacBook Pro */
429 	{ USB_VPI(USB_VENDOR_APPLE, 0x0217, FG_DRIVER_INFO(GEYSER3)) },
430 	{ USB_VPI(USB_VENDOR_APPLE, 0x0218, FG_DRIVER_INFO(GEYSER3)) },
431 	{ USB_VPI(USB_VENDOR_APPLE, 0x0219, FG_DRIVER_INFO(GEYSER3)) },
432 
433 	/* Core2 Duo MacBook & MacBook Pro */
434 	{ USB_VPI(USB_VENDOR_APPLE, 0x021a, FG_DRIVER_INFO(GEYSER4)) },
435 	{ USB_VPI(USB_VENDOR_APPLE, 0x021b, FG_DRIVER_INFO(GEYSER4)) },
436 	{ USB_VPI(USB_VENDOR_APPLE, 0x021c, FG_DRIVER_INFO(GEYSER4)) },
437 
438 	/* Core2 Duo MacBook3,1 */
439 	{ USB_VPI(USB_VENDOR_APPLE, 0x0229, FG_DRIVER_INFO(GEYSER4)) },
440 	{ USB_VPI(USB_VENDOR_APPLE, 0x022a, FG_DRIVER_INFO(GEYSER4)) },
441 	{ USB_VPI(USB_VENDOR_APPLE, 0x022b, FG_DRIVER_INFO(GEYSER4)) },
442 
443 	/* 17 inch PowerBook */
444 	{ USB_VPI(USB_VENDOR_APPLE, 0x020d, FG_DRIVER_INFO(GEYSER1_17inch)) },
445 };
446 
447 static const struct wsp_dev_params wsp_dev_params[WELLSPRING_PRODUCT_MAX] = {
448 	[WELLSPRING1] = {
449 		.caps       = 0,
450 		.tp_type    = WSP_TRACKPAD_TYPE1,
451 		.finger_data_offset  = WSP_TYPE1_FINGER_DATA_OFFSET,
452 	},
453 	[WELLSPRING2] = {
454 		.caps       = 0,
455 		.tp_type    = WSP_TRACKPAD_TYPE1,
456 		.finger_data_offset  = WSP_TYPE1_FINGER_DATA_OFFSET,
457 	},
458 	[WELLSPRING3] = {
459 		.caps       = HAS_INTEGRATED_BUTTON,
460 		.tp_type    = WSP_TRACKPAD_TYPE2,
461 		.finger_data_offset  = WSP_TYPE2_FINGER_DATA_OFFSET,
462 	},
463 	[WELLSPRING4] = {
464 		.caps       = HAS_INTEGRATED_BUTTON,
465 		.tp_type    = WSP_TRACKPAD_TYPE2,
466 		.finger_data_offset  = WSP_TYPE2_FINGER_DATA_OFFSET,
467 	},
468 	[WELLSPRING4A] = {
469 		.caps       = HAS_INTEGRATED_BUTTON,
470 		.tp_type    = WSP_TRACKPAD_TYPE2,
471 		.finger_data_offset  = WSP_TYPE2_FINGER_DATA_OFFSET,
472 	},
473 	[WELLSPRING5] = {
474 		.caps       = HAS_INTEGRATED_BUTTON,
475 		.tp_type    = WSP_TRACKPAD_TYPE2,
476 		.finger_data_offset  = WSP_TYPE2_FINGER_DATA_OFFSET,
477 	},
478 	[WELLSPRING6] = {
479 		.caps       = HAS_INTEGRATED_BUTTON,
480 		.tp_type    = WSP_TRACKPAD_TYPE2,
481 		.finger_data_offset  = WSP_TYPE2_FINGER_DATA_OFFSET,
482 	},
483 	[WELLSPRING5A] = {
484 		.caps       = HAS_INTEGRATED_BUTTON,
485 		.tp_type    = WSP_TRACKPAD_TYPE2,
486 		.finger_data_offset  = WSP_TYPE2_FINGER_DATA_OFFSET,
487 	},
488 	[WELLSPRING6A] = {
489 		.caps       = HAS_INTEGRATED_BUTTON,
490 		.tp_type    = WSP_TRACKPAD_TYPE2,
491 		.finger_data_offset  = WSP_TYPE2_FINGER_DATA_OFFSET,
492 	},
493 	[WELLSPRING7] = {
494 		.caps       = HAS_INTEGRATED_BUTTON,
495 		.tp_type    = WSP_TRACKPAD_TYPE2,
496 		.finger_data_offset  = WSP_TYPE2_FINGER_DATA_OFFSET,
497 	},
498 	[WELLSPRING7A] = {
499 		.caps       = HAS_INTEGRATED_BUTTON,
500 		.tp_type    = WSP_TRACKPAD_TYPE2,
501 		.finger_data_offset  = WSP_TYPE2_FINGER_DATA_OFFSET,
502 	},
503 	[WELLSPRING8] = {
504 		.caps       = HAS_INTEGRATED_BUTTON,
505 		.tp_type    = WSP_TRACKPAD_TYPE3,
506 		.finger_data_offset  = WSP_TYPE3_FINGER_DATA_OFFSET,
507 	},
508 };
509 
510 #define ATP_DEV(v,p,i) { USB_VPI(USB_VENDOR_##v, USB_PRODUCT_##v##_##p, i) }
511 
512 /* TODO: STRUCT_USB_HOST_ID */
513 static const struct usb_device_id wsp_devs[] = {
514 	/* MacbookAir1.1 */
515 	ATP_DEV(APPLE, WELLSPRING_ANSI, WELLSPRING_DRIVER_INFO(WELLSPRING1)),
516 	ATP_DEV(APPLE, WELLSPRING_ISO,  WELLSPRING_DRIVER_INFO(WELLSPRING1)),
517 	ATP_DEV(APPLE, WELLSPRING_JIS,  WELLSPRING_DRIVER_INFO(WELLSPRING1)),
518 
519 	/* MacbookProPenryn, aka wellspring2 */
520 	ATP_DEV(APPLE, WELLSPRING2_ANSI, WELLSPRING_DRIVER_INFO(WELLSPRING2)),
521 	ATP_DEV(APPLE, WELLSPRING2_ISO,  WELLSPRING_DRIVER_INFO(WELLSPRING2)),
522 	ATP_DEV(APPLE, WELLSPRING2_JIS,  WELLSPRING_DRIVER_INFO(WELLSPRING2)),
523 
524 	/* Macbook5,1 (unibody), aka wellspring3 */
525 	ATP_DEV(APPLE, WELLSPRING3_ANSI, WELLSPRING_DRIVER_INFO(WELLSPRING3)),
526 	ATP_DEV(APPLE, WELLSPRING3_ISO,  WELLSPRING_DRIVER_INFO(WELLSPRING3)),
527 	ATP_DEV(APPLE, WELLSPRING3_JIS,  WELLSPRING_DRIVER_INFO(WELLSPRING3)),
528 
529 	/* MacbookAir3,2 (unibody), aka wellspring4 */
530 	ATP_DEV(APPLE, WELLSPRING4_ANSI, WELLSPRING_DRIVER_INFO(WELLSPRING4)),
531 	ATP_DEV(APPLE, WELLSPRING4_ISO,  WELLSPRING_DRIVER_INFO(WELLSPRING4)),
532 	ATP_DEV(APPLE, WELLSPRING4_JIS,  WELLSPRING_DRIVER_INFO(WELLSPRING4)),
533 
534 	/* MacbookAir3,1 (unibody), aka wellspring4 */
535 	ATP_DEV(APPLE, WELLSPRING4A_ANSI, WELLSPRING_DRIVER_INFO(WELLSPRING4A)),
536 	ATP_DEV(APPLE, WELLSPRING4A_ISO,  WELLSPRING_DRIVER_INFO(WELLSPRING4A)),
537 	ATP_DEV(APPLE, WELLSPRING4A_JIS,  WELLSPRING_DRIVER_INFO(WELLSPRING4A)),
538 
539 	/* Macbook8 (unibody, March 2011) */
540 	ATP_DEV(APPLE, WELLSPRING5_ANSI, WELLSPRING_DRIVER_INFO(WELLSPRING5)),
541 	ATP_DEV(APPLE, WELLSPRING5_ISO,  WELLSPRING_DRIVER_INFO(WELLSPRING5)),
542 	ATP_DEV(APPLE, WELLSPRING5_JIS,  WELLSPRING_DRIVER_INFO(WELLSPRING5)),
543 
544 	/* MacbookAir4,1 (unibody, July 2011) */
545 	ATP_DEV(APPLE, WELLSPRING6A_ANSI, WELLSPRING_DRIVER_INFO(WELLSPRING6A)),
546 	ATP_DEV(APPLE, WELLSPRING6A_ISO,  WELLSPRING_DRIVER_INFO(WELLSPRING6A)),
547 	ATP_DEV(APPLE, WELLSPRING6A_JIS,  WELLSPRING_DRIVER_INFO(WELLSPRING6A)),
548 
549 	/* MacbookAir4,2 (unibody, July 2011) */
550 	ATP_DEV(APPLE, WELLSPRING6_ANSI, WELLSPRING_DRIVER_INFO(WELLSPRING6)),
551 	ATP_DEV(APPLE, WELLSPRING6_ISO,  WELLSPRING_DRIVER_INFO(WELLSPRING6)),
552 	ATP_DEV(APPLE, WELLSPRING6_JIS,  WELLSPRING_DRIVER_INFO(WELLSPRING6)),
553 
554 	/* Macbook8,2 (unibody) */
555 	ATP_DEV(APPLE, WELLSPRING5A_ANSI, WELLSPRING_DRIVER_INFO(WELLSPRING5A)),
556 	ATP_DEV(APPLE, WELLSPRING5A_ISO,  WELLSPRING_DRIVER_INFO(WELLSPRING5A)),
557 	ATP_DEV(APPLE, WELLSPRING5A_JIS,  WELLSPRING_DRIVER_INFO(WELLSPRING5A)),
558 
559 	/* MacbookPro10,1 (unibody, June 2012) */
560 	/* MacbookPro11,? (unibody, June 2013) */
561 	ATP_DEV(APPLE, WELLSPRING7_ANSI, WELLSPRING_DRIVER_INFO(WELLSPRING7)),
562 	ATP_DEV(APPLE, WELLSPRING7_ISO,  WELLSPRING_DRIVER_INFO(WELLSPRING7)),
563 	ATP_DEV(APPLE, WELLSPRING7_JIS,  WELLSPRING_DRIVER_INFO(WELLSPRING7)),
564 
565 	/* MacbookPro10,2 (unibody, October 2012) */
566 	ATP_DEV(APPLE, WELLSPRING7A_ANSI, WELLSPRING_DRIVER_INFO(WELLSPRING7A)),
567 	ATP_DEV(APPLE, WELLSPRING7A_ISO,  WELLSPRING_DRIVER_INFO(WELLSPRING7A)),
568 	ATP_DEV(APPLE, WELLSPRING7A_JIS,  WELLSPRING_DRIVER_INFO(WELLSPRING7A)),
569 
570 	/* MacbookAir6,2 (unibody, June 2013) */
571 	ATP_DEV(APPLE, WELLSPRING8_ANSI, WELLSPRING_DRIVER_INFO(WELLSPRING8)),
572 	ATP_DEV(APPLE, WELLSPRING8_ISO,  WELLSPRING_DRIVER_INFO(WELLSPRING8)),
573 	ATP_DEV(APPLE, WELLSPRING8_JIS,  WELLSPRING_DRIVER_INFO(WELLSPRING8)),
574 };
575 
576 typedef enum atp_stroke_type {
577 	ATP_STROKE_TOUCH,
578 	ATP_STROKE_SLIDE,
579 } atp_stroke_type;
580 
581 typedef enum atp_axis {
582 	X = 0,
583 	Y = 1,
584 	NUM_AXES
585 } atp_axis;
586 
587 #define ATP_FIFO_BUF_SIZE        8 /* bytes */
588 #define ATP_FIFO_QUEUE_MAXLEN   50 /* units */
589 
590 enum {
591 	ATP_INTR_DT,
592 	ATP_RESET,
593 	ATP_N_TRANSFER,
594 };
595 
596 typedef struct fg_stroke_component {
597 	/* Fields encapsulating the pressure-span. */
598 	u_int loc;              /* location (scaled) */
599 	u_int cum_pressure;     /* cumulative compression */
600 	u_int max_cum_pressure; /* max cumulative compression */
601 	boolean_t matched; /*to track components as they match against pspans.*/
602 
603 	int   delta_mickeys;    /* change in location (un-smoothened movement)*/
604 } fg_stroke_component_t;
605 
606 /*
607  * The following structure captures a finger contact with the
608  * touchpad. A stroke comprises two p-span components and some state.
609  */
610 typedef struct atp_stroke {
611 	TAILQ_ENTRY(atp_stroke) entry;
612 
613 	atp_stroke_type type;
614 	uint32_t        flags; /* the state of this stroke */
615 #define ATSF_ZOMBIE 0x1
616 	boolean_t       matched;          /* to track match against fingers.*/
617 
618 	struct timeval  ctime; /* create time; for coincident siblings. */
619 
620 	/*
621 	 * Unit: interrupts; we maintain this value in
622 	 * addition to 'ctime' in order to avoid the
623 	 * expensive call to microtime() at every
624 	 * interrupt.
625 	 */
626 	uint32_t age;
627 
628 	/* Location */
629 	int x;
630 	int y;
631 
632 	/* Fields containing information about movement. */
633 	int   instantaneous_dx; /* curr. change in X location (un-smoothened) */
634 	int   instantaneous_dy; /* curr. change in Y location (un-smoothened) */
635 	int   pending_dx;       /* cum. of pending short movements */
636 	int   pending_dy;       /* cum. of pending short movements */
637 	int   movement_dx;      /* interpreted smoothened movement */
638 	int   movement_dy;      /* interpreted smoothened movement */
639 	int   cum_movement_x;   /* cum. horizontal movement */
640 	int   cum_movement_y;   /* cum. vertical movement */
641 
642 	/*
643 	 * The following member is relevant only for fountain-geyser trackpads.
644 	 * For these, there is the need to track pressure-spans and cumulative
645 	 * pressures for stroke components.
646 	 */
647 	fg_stroke_component_t components[NUM_AXES];
648 } atp_stroke_t;
649 
650 struct atp_softc; /* forward declaration */
651 typedef void (*sensor_data_interpreter_t)(struct atp_softc *sc, u_int len);
652 
653 struct atp_softc {
654 	device_t            sc_dev;
655 	struct usb_device  *sc_usb_device;
656 	struct mtx          sc_mutex; /* for synchronization */
657 	struct usb_fifo_sc  sc_fifo;
658 
659 #define	MODE_LENGTH 8
660 	char                sc_mode_bytes[MODE_LENGTH]; /* device mode */
661 
662 	trackpad_family_t   sc_family;
663 	const void         *sc_params; /* device configuration */
664 	sensor_data_interpreter_t sensor_data_interpreter;
665 
666 	mousehw_t           sc_hw;
667 	mousemode_t         sc_mode;
668 	mousestatus_t       sc_status;
669 
670 	u_int               sc_state;
671 #define ATP_ENABLED          0x01
672 #define ATP_ZOMBIES_EXIST    0x02
673 #define ATP_DOUBLE_TAP_DRAG  0x04
674 #define ATP_VALID            0x08
675 
676 	struct usb_xfer    *sc_xfer[ATP_N_TRANSFER];
677 
678 	u_int               sc_pollrate;
679 	int                 sc_fflags;
680 
681 	atp_stroke_t        sc_strokes_data[ATP_MAX_STROKES];
682 	TAILQ_HEAD(,atp_stroke) sc_stroke_free;
683 	TAILQ_HEAD(,atp_stroke) sc_stroke_used;
684 	u_int               sc_n_strokes;
685 
686 	struct callout	    sc_callout;
687 
688 	/*
689 	 * button status. Set to non-zero if the mouse-button is physically
690 	 * pressed. This state variable is exposed through softc to allow
691 	 * reap_sibling_zombies to avoid registering taps while the trackpad
692 	 * button is pressed.
693          */
694 	uint8_t             sc_ibtn;
695 
696 	/*
697 	 * Time when touch zombies were last reaped; useful for detecting
698 	 * double-touch-n-drag.
699 	 */
700 	struct timeval      sc_touch_reap_time;
701 
702 	u_int	            sc_idlecount;
703 
704 	/* Regarding the data transferred from t-pad in USB INTR packets. */
705 	u_int   sc_expected_sensor_data_len;
706 	uint8_t sc_sensor_data[ATP_SENSOR_DATA_BUF_MAX] __aligned(4);
707 
708 	int      sc_cur_x[FG_MAX_XSENSORS];      /* current sensor readings */
709 	int      sc_cur_y[FG_MAX_YSENSORS];
710 	int      sc_base_x[FG_MAX_XSENSORS];     /* base sensor readings */
711 	int      sc_base_y[FG_MAX_YSENSORS];
712 	int      sc_pressure_x[FG_MAX_XSENSORS]; /* computed pressures */
713 	int      sc_pressure_y[FG_MAX_YSENSORS];
714 	fg_pspan sc_pspans_x[FG_MAX_PSPANS_PER_AXIS];
715 	fg_pspan sc_pspans_y[FG_MAX_PSPANS_PER_AXIS];
716 };
717 
718 /*
719  * The last byte of the fountain-geyser sensor data contains status bits; the
720  * following values define the meanings of these bits.
721  * (only Geyser 3/4)
722  */
723 enum geyser34_status_bits {
724 	FG_STATUS_BUTTON      = (uint8_t)0x01, /* The button was pressed */
725 	FG_STATUS_BASE_UPDATE = (uint8_t)0x04, /* Data from an untouched pad.*/
726 };
727 
728 typedef enum interface_mode {
729 	RAW_SENSOR_MODE = (uint8_t)0x01,
730 	HID_MODE        = (uint8_t)0x08
731 } interface_mode;
732 
733 
734 /*
735  * function prototypes
736  */
737 static usb_fifo_cmd_t   atp_start_read;
738 static usb_fifo_cmd_t   atp_stop_read;
739 static usb_fifo_open_t  atp_open;
740 static usb_fifo_close_t atp_close;
741 static usb_fifo_ioctl_t atp_ioctl;
742 
743 static struct usb_fifo_methods atp_fifo_methods = {
744 	.f_open       = &atp_open,
745 	.f_close      = &atp_close,
746 	.f_ioctl      = &atp_ioctl,
747 	.f_start_read = &atp_start_read,
748 	.f_stop_read  = &atp_stop_read,
749 	.basename[0]  = ATP_DRIVER_NAME,
750 };
751 
752 /* device initialization and shutdown */
753 static usb_error_t   atp_set_device_mode(struct atp_softc *, interface_mode);
754 static void	     atp_reset_callback(struct usb_xfer *, usb_error_t);
755 static int	     atp_enable(struct atp_softc *);
756 static void	     atp_disable(struct atp_softc *);
757 
758 /* sensor interpretation */
759 static void	     fg_interpret_sensor_data(struct atp_softc *, u_int);
760 static void	     fg_extract_sensor_data(const int8_t *, u_int, atp_axis,
761     int *, enum fountain_geyser_trackpad_type);
762 static void	     fg_get_pressures(int *, const int *, const int *, int);
763 static void	     fg_detect_pspans(int *, u_int, u_int, fg_pspan *, u_int *);
764 static void	     wsp_interpret_sensor_data(struct atp_softc *, u_int);
765 
766 /* movement detection */
767 static boolean_t     fg_match_stroke_component(fg_stroke_component_t *,
768     const fg_pspan *, atp_stroke_type);
769 static void	     fg_match_strokes_against_pspans(struct atp_softc *,
770     atp_axis, fg_pspan *, u_int, u_int);
771 static boolean_t     wsp_match_strokes_against_fingers(struct atp_softc *,
772     wsp_finger_t *, u_int);
773 static boolean_t     fg_update_strokes(struct atp_softc *, fg_pspan *, u_int,
774     fg_pspan *, u_int);
775 static boolean_t     wsp_update_strokes(struct atp_softc *,
776     wsp_finger_t [WSP_MAX_FINGERS], u_int);
777 static void fg_add_stroke(struct atp_softc *, const fg_pspan *, const fg_pspan *);
778 static void	     fg_add_new_strokes(struct atp_softc *, fg_pspan *,
779     u_int, fg_pspan *, u_int);
780 static void wsp_add_stroke(struct atp_softc *, const wsp_finger_t *);
781 static void	     atp_advance_stroke_state(struct atp_softc *,
782     atp_stroke_t *, boolean_t *);
783 static boolean_t atp_stroke_has_small_movement(const atp_stroke_t *);
784 static void	     atp_update_pending_mickeys(atp_stroke_t *);
785 static boolean_t     atp_compute_stroke_movement(atp_stroke_t *);
786 static void	     atp_terminate_stroke(struct atp_softc *, atp_stroke_t *);
787 
788 /* tap detection */
789 static boolean_t atp_is_horizontal_scroll(const atp_stroke_t *);
790 static boolean_t atp_is_vertical_scroll(const atp_stroke_t *);
791 static void	     atp_reap_sibling_zombies(void *);
792 static void	     atp_convert_to_slide(struct atp_softc *, atp_stroke_t *);
793 
794 /* updating fifo */
795 static void	     atp_reset_buf(struct atp_softc *);
796 static void	     atp_add_to_queue(struct atp_softc *, int, int, int, uint32_t);
797 
798 /* Device methods. */
799 static device_probe_t  atp_probe;
800 static device_attach_t atp_attach;
801 static device_detach_t atp_detach;
802 static usb_callback_t  atp_intr;
803 
804 static const struct usb_config atp_xfer_config[ATP_N_TRANSFER] = {
805 	[ATP_INTR_DT] = {
806 		.type      = UE_INTERRUPT,
807 		.endpoint  = UE_ADDR_ANY,
808 		.direction = UE_DIR_IN,
809 		.flags = {
810 			.pipe_bof = 1, /* block pipe on failure */
811 			.short_xfer_ok = 1,
812 		},
813 		.bufsize   = ATP_SENSOR_DATA_BUF_MAX,
814 		.callback  = &atp_intr,
815 	},
816 	[ATP_RESET] = {
817 		.type      = UE_CONTROL,
818 		.endpoint  = 0, /* Control pipe */
819 		.direction = UE_DIR_ANY,
820 		.bufsize   = sizeof(struct usb_device_request) + MODE_LENGTH,
821 		.callback  = &atp_reset_callback,
822 		.interval  = 0,  /* no pre-delay */
823 	},
824 };
825 
826 static atp_stroke_t *
827 atp_alloc_stroke(struct atp_softc *sc)
828 {
829 	atp_stroke_t *pstroke;
830 
831 	pstroke = TAILQ_FIRST(&sc->sc_stroke_free);
832 	if (pstroke == NULL)
833 		goto done;
834 
835 	TAILQ_REMOVE(&sc->sc_stroke_free, pstroke, entry);
836 	memset(pstroke, 0, sizeof(*pstroke));
837 	TAILQ_INSERT_TAIL(&sc->sc_stroke_used, pstroke, entry);
838 
839 	sc->sc_n_strokes++;
840 done:
841 	return (pstroke);
842 }
843 
844 static void
845 atp_free_stroke(struct atp_softc *sc, atp_stroke_t *pstroke)
846 {
847 	if (pstroke == NULL)
848 		return;
849 
850 	sc->sc_n_strokes--;
851 
852 	TAILQ_REMOVE(&sc->sc_stroke_used, pstroke, entry);
853 	TAILQ_INSERT_TAIL(&sc->sc_stroke_free, pstroke, entry);
854 }
855 
856 static void
857 atp_init_stroke_pool(struct atp_softc *sc)
858 {
859 	u_int x;
860 
861 	TAILQ_INIT(&sc->sc_stroke_free);
862 	TAILQ_INIT(&sc->sc_stroke_used);
863 
864 	sc->sc_n_strokes = 0;
865 
866 	memset(&sc->sc_strokes_data, 0, sizeof(sc->sc_strokes_data));
867 
868 	for (x = 0; x != ATP_MAX_STROKES; x++) {
869 		TAILQ_INSERT_TAIL(&sc->sc_stroke_free, &sc->sc_strokes_data[x],
870 		    entry);
871 	}
872 }
873 
874 static usb_error_t
875 atp_set_device_mode(struct atp_softc *sc, interface_mode newMode)
876 {
877 	uint8_t mode_value;
878 	usb_error_t err;
879 
880 	if ((newMode != RAW_SENSOR_MODE) && (newMode != HID_MODE))
881 		return (USB_ERR_INVAL);
882 
883 	if ((newMode == RAW_SENSOR_MODE) &&
884 	    (sc->sc_family == TRACKPAD_FAMILY_FOUNTAIN_GEYSER))
885 		mode_value = (uint8_t)0x04;
886 	else
887 		mode_value = newMode;
888 
889 	err = usbd_req_get_report(sc->sc_usb_device, NULL /* mutex */,
890 	    sc->sc_mode_bytes, sizeof(sc->sc_mode_bytes), 0 /* interface idx */,
891 	    0x03 /* type */, 0x00 /* id */);
892 	if (err != USB_ERR_NORMAL_COMPLETION) {
893 		DPRINTF("Failed to read device mode (%d)\n", err);
894 		return (err);
895 	}
896 
897 	if (sc->sc_mode_bytes[0] == mode_value)
898 		return (err);
899 
900 	/*
901 	 * XXX Need to wait at least 250ms for hardware to get
902 	 * ready. The device mode handling appears to be handled
903 	 * asynchronously and we should not issue these commands too
904 	 * quickly.
905 	 */
906 	pause("WHW", hz / 4);
907 
908 	sc->sc_mode_bytes[0] = mode_value;
909 	return (usbd_req_set_report(sc->sc_usb_device, NULL /* mutex */,
910 	    sc->sc_mode_bytes, sizeof(sc->sc_mode_bytes), 0 /* interface idx */,
911 	    0x03 /* type */, 0x00 /* id */));
912 }
913 
914 static void
915 atp_reset_callback(struct usb_xfer *xfer, usb_error_t error)
916 {
917 	usb_device_request_t   req;
918 	struct usb_page_cache *pc;
919 	struct atp_softc      *sc = usbd_xfer_softc(xfer);
920 
921 	uint8_t mode_value;
922 	if (sc->sc_family == TRACKPAD_FAMILY_FOUNTAIN_GEYSER)
923 		mode_value = 0x04;
924 	else
925 		mode_value = RAW_SENSOR_MODE;
926 
927 	switch (USB_GET_STATE(xfer)) {
928 	case USB_ST_SETUP:
929 		sc->sc_mode_bytes[0] = mode_value;
930 		req.bmRequestType = UT_WRITE_CLASS_INTERFACE;
931 		req.bRequest = UR_SET_REPORT;
932 		USETW2(req.wValue,
933 		    (uint8_t)0x03 /* type */, (uint8_t)0x00 /* id */);
934 		USETW(req.wIndex, 0);
935 		USETW(req.wLength, MODE_LENGTH);
936 
937 		pc = usbd_xfer_get_frame(xfer, 0);
938 		usbd_copy_in(pc, 0, &req, sizeof(req));
939 		pc = usbd_xfer_get_frame(xfer, 1);
940 		usbd_copy_in(pc, 0, sc->sc_mode_bytes, MODE_LENGTH);
941 
942 		usbd_xfer_set_frame_len(xfer, 0, sizeof(req));
943 		usbd_xfer_set_frame_len(xfer, 1, MODE_LENGTH);
944 		usbd_xfer_set_frames(xfer, 2);
945 		usbd_transfer_submit(xfer);
946 		break;
947 
948 	case USB_ST_TRANSFERRED:
949 	default:
950 		break;
951 	}
952 }
953 
954 static int
955 atp_enable(struct atp_softc *sc)
956 {
957 	if (sc->sc_state & ATP_ENABLED)
958 		return (0);
959 
960 	/* reset status */
961 	memset(&sc->sc_status, 0, sizeof(sc->sc_status));
962 
963 	atp_init_stroke_pool(sc);
964 
965 	sc->sc_state |= ATP_ENABLED;
966 
967 	DPRINTFN(ATP_LLEVEL_INFO, "enabled atp\n");
968 	return (0);
969 }
970 
971 static void
972 atp_disable(struct atp_softc *sc)
973 {
974 	sc->sc_state &= ~(ATP_ENABLED | ATP_VALID);
975 	DPRINTFN(ATP_LLEVEL_INFO, "disabled atp\n");
976 }
977 
978 static void
979 fg_interpret_sensor_data(struct atp_softc *sc, u_int data_len)
980 {
981 	u_int n_xpspans = 0;
982 	u_int n_ypspans = 0;
983 	uint8_t status_bits;
984 
985 	const struct fg_dev_params *params =
986 	    (const struct fg_dev_params *)sc->sc_params;
987 
988 	fg_extract_sensor_data(sc->sc_sensor_data, params->n_xsensors, X,
989 	    sc->sc_cur_x, params->prot);
990 	fg_extract_sensor_data(sc->sc_sensor_data, params->n_ysensors, Y,
991 	    sc->sc_cur_y, params->prot);
992 
993 	/*
994 	 * If this is the initial update (from an untouched
995 	 * pad), we should set the base values for the sensor
996 	 * data; deltas with respect to these base values can
997 	 * be used as pressure readings subsequently.
998 	 */
999 	status_bits = sc->sc_sensor_data[params->data_len - 1];
1000 	if (((params->prot == FG_TRACKPAD_TYPE_GEYSER3) ||
1001 	     (params->prot == FG_TRACKPAD_TYPE_GEYSER4))  &&
1002 	    ((sc->sc_state & ATP_VALID) == 0)) {
1003 		if (status_bits & FG_STATUS_BASE_UPDATE) {
1004 			memcpy(sc->sc_base_x, sc->sc_cur_x,
1005 			    params->n_xsensors * sizeof(*sc->sc_base_x));
1006 			memcpy(sc->sc_base_y, sc->sc_cur_y,
1007 			    params->n_ysensors * sizeof(*sc->sc_base_y));
1008 			sc->sc_state |= ATP_VALID;
1009 			return;
1010 		}
1011 	}
1012 
1013 	/* Get pressure readings and detect p-spans for both axes. */
1014 	fg_get_pressures(sc->sc_pressure_x, sc->sc_cur_x, sc->sc_base_x,
1015 	    params->n_xsensors);
1016 	fg_detect_pspans(sc->sc_pressure_x, params->n_xsensors,
1017 	    FG_MAX_PSPANS_PER_AXIS, sc->sc_pspans_x, &n_xpspans);
1018 	fg_get_pressures(sc->sc_pressure_y, sc->sc_cur_y, sc->sc_base_y,
1019 	    params->n_ysensors);
1020 	fg_detect_pspans(sc->sc_pressure_y, params->n_ysensors,
1021 	    FG_MAX_PSPANS_PER_AXIS, sc->sc_pspans_y, &n_ypspans);
1022 
1023 	/* Update strokes with new pspans to detect movements. */
1024 	if (fg_update_strokes(sc, sc->sc_pspans_x, n_xpspans, sc->sc_pspans_y, n_ypspans))
1025 		sc->sc_status.flags |= MOUSE_POSCHANGED;
1026 
1027 	sc->sc_ibtn = (status_bits & FG_STATUS_BUTTON) ? MOUSE_BUTTON1DOWN : 0;
1028 	sc->sc_status.button = sc->sc_ibtn;
1029 
1030 	/*
1031 	 * The Fountain/Geyser device continues to trigger interrupts
1032 	 * at a fast rate even after touchpad activity has
1033 	 * stopped. Upon detecting that the device has remained idle
1034 	 * beyond a threshold, we reinitialize it to silence the
1035 	 * interrupts.
1036 	 */
1037 	if ((sc->sc_status.flags  == 0) && (sc->sc_n_strokes == 0)) {
1038 		sc->sc_idlecount++;
1039 		if (sc->sc_idlecount >= ATP_IDLENESS_THRESHOLD) {
1040 			/*
1041 			 * Use the last frame before we go idle for
1042 			 * calibration on pads which do not send
1043 			 * calibration frames.
1044 			 */
1045 			const struct fg_dev_params *params =
1046 			    (const struct fg_dev_params *)sc->sc_params;
1047 
1048 			DPRINTFN(ATP_LLEVEL_INFO, "idle\n");
1049 
1050 			if (params->prot < FG_TRACKPAD_TYPE_GEYSER3) {
1051 				memcpy(sc->sc_base_x, sc->sc_cur_x,
1052 				    params->n_xsensors * sizeof(*(sc->sc_base_x)));
1053 				memcpy(sc->sc_base_y, sc->sc_cur_y,
1054 				    params->n_ysensors * sizeof(*(sc->sc_base_y)));
1055 			}
1056 
1057 			sc->sc_idlecount = 0;
1058 			usbd_transfer_start(sc->sc_xfer[ATP_RESET]);
1059 		}
1060 	} else {
1061 		sc->sc_idlecount = 0;
1062 	}
1063 }
1064 
1065 /*
1066  * Interpret the data from the X and Y pressure sensors. This function
1067  * is called separately for the X and Y sensor arrays. The data in the
1068  * USB packet is laid out in the following manner:
1069  *
1070  * sensor_data:
1071  *            --,--,Y1,Y2,--,Y3,Y4,--,Y5,...,Y10, ... X1,X2,--,X3,X4
1072  *  indices:   0  1  2  3  4  5  6  7  8 ...  15  ... 20 21 22 23 24
1073  *
1074  * '--' (in the above) indicates that the value is unimportant.
1075  *
1076  * Information about the above layout was obtained from the
1077  * implementation of the AppleTouch driver in Linux.
1078  *
1079  * parameters:
1080  *   sensor_data
1081  *       raw sensor data from the USB packet.
1082  *   num
1083  *       The number of elements in the array 'arr'.
1084  *   axis
1085  *       Axis of data to fetch
1086  *   arr
1087  *       The array to be initialized with the readings.
1088  *   prot
1089  *       The protocol to use to interpret the data
1090  */
1091 static void
1092 fg_extract_sensor_data(const int8_t *sensor_data, u_int num, atp_axis axis,
1093     int	*arr, enum fountain_geyser_trackpad_type prot)
1094 {
1095 	u_int i;
1096 	u_int di;   /* index into sensor data */
1097 
1098 	switch (prot) {
1099 	case FG_TRACKPAD_TYPE_GEYSER1:
1100 		/*
1101 		 * For Geyser 1, the sensors are laid out in pairs
1102 		 * every 5 bytes.
1103 		 */
1104 		for (i = 0, di = (axis == Y) ? 1 : 2; i < 8; di += 5, i++) {
1105 			arr[i] = sensor_data[di];
1106 			arr[i+8] = sensor_data[di+2];
1107 			if ((axis == X) && (num > 16))
1108 				arr[i+16] = sensor_data[di+40];
1109 		}
1110 
1111 		break;
1112 	case FG_TRACKPAD_TYPE_GEYSER2:
1113 		for (i = 0, di = (axis == Y) ? 1 : 19; i < num; /* empty */ ) {
1114 			arr[i++] = sensor_data[di++];
1115 			arr[i++] = sensor_data[di++];
1116 			di++;
1117 		}
1118 		break;
1119 	case FG_TRACKPAD_TYPE_GEYSER3:
1120 	case FG_TRACKPAD_TYPE_GEYSER4:
1121 		for (i = 0, di = (axis == Y) ? 2 : 20; i < num; /* empty */ ) {
1122 			arr[i++] = sensor_data[di++];
1123 			arr[i++] = sensor_data[di++];
1124 			di++;
1125 		}
1126 		break;
1127 	default:
1128 		break;
1129 	}
1130 }
1131 
1132 static void
1133 fg_get_pressures(int *p, const int *cur, const int *base, int n)
1134 {
1135 	int i;
1136 
1137 	for (i = 0; i < n; i++) {
1138 		p[i] = cur[i] - base[i];
1139 		if (p[i] > 127)
1140 			p[i] -= 256;
1141 		if (p[i] < -127)
1142 			p[i] += 256;
1143 		if (p[i] < 0)
1144 			p[i] = 0;
1145 
1146 		/*
1147 		 * Shave off pressures below the noise-pressure
1148 		 * threshold; this will reduce the contribution from
1149 		 * lower pressure readings.
1150 		 */
1151 		if ((u_int)p[i] <= FG_SENSOR_NOISE_THRESHOLD)
1152 			p[i] = 0; /* filter away noise */
1153 		else
1154 			p[i] -= FG_SENSOR_NOISE_THRESHOLD;
1155 	}
1156 }
1157 
1158 static void
1159 fg_detect_pspans(int *p, u_int num_sensors,
1160     u_int      max_spans, /* max # of pspans permitted */
1161     fg_pspan  *spans,     /* finger spans */
1162     u_int     *nspans_p)  /* num spans detected */
1163 {
1164 	u_int i;
1165 	int   maxp;             /* max pressure seen within a span */
1166 	u_int num_spans = 0;
1167 
1168 	enum fg_pspan_state {
1169 		ATP_PSPAN_INACTIVE,
1170 		ATP_PSPAN_INCREASING,
1171 		ATP_PSPAN_DECREASING,
1172 	} state; /* state of the pressure span */
1173 
1174 	/*
1175 	 * The following is a simple state machine to track
1176 	 * the phase of the pressure span.
1177 	 */
1178 	memset(spans, 0, max_spans * sizeof(fg_pspan));
1179 	maxp = 0;
1180 	state = ATP_PSPAN_INACTIVE;
1181 	for (i = 0; i < num_sensors; i++) {
1182 		if (num_spans >= max_spans)
1183 			break;
1184 
1185 		if (p[i] == 0) {
1186 			if (state == ATP_PSPAN_INACTIVE) {
1187 				/*
1188 				 * There is no pressure information for this
1189 				 * sensor, and we aren't tracking a finger.
1190 				 */
1191 				continue;
1192 			} else {
1193 				state = ATP_PSPAN_INACTIVE;
1194 				maxp = 0;
1195 				num_spans++;
1196 			}
1197 		} else {
1198 			switch (state) {
1199 			case ATP_PSPAN_INACTIVE:
1200 				state = ATP_PSPAN_INCREASING;
1201 				maxp  = p[i];
1202 				break;
1203 
1204 			case ATP_PSPAN_INCREASING:
1205 				if (p[i] > maxp)
1206 					maxp = p[i];
1207 				else if (p[i] <= (maxp >> 1))
1208 					state = ATP_PSPAN_DECREASING;
1209 				break;
1210 
1211 			case ATP_PSPAN_DECREASING:
1212 				if (p[i] > p[i - 1]) {
1213 					/*
1214 					 * This is the beginning of
1215 					 * another span; change state
1216 					 * to give the appearance that
1217 					 * we're starting from an
1218 					 * inactive span, and then
1219 					 * re-process this reading in
1220 					 * the next iteration.
1221 					 */
1222 					num_spans++;
1223 					state = ATP_PSPAN_INACTIVE;
1224 					maxp  = 0;
1225 					i--;
1226 					continue;
1227 				}
1228 				break;
1229 			}
1230 
1231 			/* Update the finger span with this reading. */
1232 			spans[num_spans].width++;
1233 			spans[num_spans].cum += p[i];
1234 			spans[num_spans].cog += p[i] * (i + 1);
1235 		}
1236 	}
1237 	if (state != ATP_PSPAN_INACTIVE)
1238 		num_spans++;    /* close the last finger span */
1239 
1240 	/* post-process the spans */
1241 	for (i = 0; i < num_spans; i++) {
1242 		/* filter away unwanted pressure spans */
1243 		if ((spans[i].cum < FG_PSPAN_MIN_CUM_PRESSURE) ||
1244 		    (spans[i].width > FG_PSPAN_MAX_WIDTH)) {
1245 			if ((i + 1) < num_spans) {
1246 				memcpy(&spans[i], &spans[i + 1],
1247 				    (num_spans - i - 1) * sizeof(fg_pspan));
1248 				i--;
1249 			}
1250 			num_spans--;
1251 			continue;
1252 		}
1253 
1254 		/* compute this span's representative location */
1255 		spans[i].loc = spans[i].cog * FG_SCALE_FACTOR /
1256 			spans[i].cum;
1257 
1258 		spans[i].matched = false; /* not yet matched against a stroke */
1259 	}
1260 
1261 	*nspans_p = num_spans;
1262 }
1263 
1264 static void
1265 wsp_interpret_sensor_data(struct atp_softc *sc, u_int data_len)
1266 {
1267 	const struct wsp_dev_params *params = sc->sc_params;
1268 	wsp_finger_t fingers[WSP_MAX_FINGERS];
1269 	struct wsp_finger_sensor_data *source_fingerp;
1270 	u_int n_source_fingers;
1271 	u_int n_fingers;
1272 	u_int i;
1273 
1274 	/* validate sensor data length */
1275 	if ((data_len < params->finger_data_offset) ||
1276 	    ((data_len - params->finger_data_offset) %
1277 	     WSP_SIZEOF_FINGER_SENSOR_DATA) != 0)
1278 		return;
1279 
1280 	/* compute number of source fingers */
1281 	n_source_fingers = (data_len - params->finger_data_offset) /
1282 	    WSP_SIZEOF_FINGER_SENSOR_DATA;
1283 
1284 	if (n_source_fingers > WSP_MAX_FINGERS)
1285 		n_source_fingers = WSP_MAX_FINGERS;
1286 
1287 	/* iterate over the source data collecting useful fingers */
1288 	n_fingers = 0;
1289 	source_fingerp = (struct wsp_finger_sensor_data *)(sc->sc_sensor_data +
1290 	     params->finger_data_offset);
1291 
1292 	for (i = 0; i < n_source_fingers; i++, source_fingerp++) {
1293 		/* swap endianness, if any */
1294 		if (le16toh(0x1234) != 0x1234) {
1295 			source_fingerp->origin      = le16toh((uint16_t)source_fingerp->origin);
1296 			source_fingerp->abs_x       = le16toh((uint16_t)source_fingerp->abs_x);
1297 			source_fingerp->abs_y       = le16toh((uint16_t)source_fingerp->abs_y);
1298 			source_fingerp->rel_x       = le16toh((uint16_t)source_fingerp->rel_x);
1299 			source_fingerp->rel_y       = le16toh((uint16_t)source_fingerp->rel_y);
1300 			source_fingerp->tool_major  = le16toh((uint16_t)source_fingerp->tool_major);
1301 			source_fingerp->tool_minor  = le16toh((uint16_t)source_fingerp->tool_minor);
1302 			source_fingerp->orientation = le16toh((uint16_t)source_fingerp->orientation);
1303 			source_fingerp->touch_major = le16toh((uint16_t)source_fingerp->touch_major);
1304 			source_fingerp->touch_minor = le16toh((uint16_t)source_fingerp->touch_minor);
1305 			source_fingerp->multi       = le16toh((uint16_t)source_fingerp->multi);
1306 		}
1307 
1308 		/* check for minium threshold */
1309 		if (source_fingerp->touch_major == 0)
1310 			continue;
1311 
1312 		fingers[n_fingers].matched = false;
1313 		fingers[n_fingers].x       = source_fingerp->abs_x;
1314 		fingers[n_fingers].y       = -source_fingerp->abs_y;
1315 
1316 		n_fingers++;
1317 	}
1318 
1319 	if ((sc->sc_n_strokes == 0) && (n_fingers == 0))
1320 		return;
1321 
1322 	if (wsp_update_strokes(sc, fingers, n_fingers))
1323 		sc->sc_status.flags |= MOUSE_POSCHANGED;
1324 
1325 	switch(params->tp_type) {
1326 	case WSP_TRACKPAD_TYPE2:
1327 		sc->sc_ibtn = sc->sc_sensor_data[WSP_TYPE2_BUTTON_DATA_OFFSET];
1328 		break;
1329 	case WSP_TRACKPAD_TYPE3:
1330 		sc->sc_ibtn = sc->sc_sensor_data[WSP_TYPE3_BUTTON_DATA_OFFSET];
1331 		break;
1332 	default:
1333 		break;
1334 	}
1335 	sc->sc_status.button = sc->sc_ibtn ? MOUSE_BUTTON1DOWN : 0;
1336 }
1337 
1338 /*
1339  * Match a pressure-span against a stroke-component. If there is a
1340  * match, update the component's state and return true.
1341  */
1342 static boolean_t
1343 fg_match_stroke_component(fg_stroke_component_t *component,
1344     const fg_pspan *pspan, atp_stroke_type stroke_type)
1345 {
1346 	int   delta_mickeys;
1347 	u_int min_pressure;
1348 
1349 	delta_mickeys = pspan->loc - component->loc;
1350 
1351 	if (abs(delta_mickeys) > (int)FG_MAX_DELTA_MICKEYS)
1352 		return (false); /* the finger span is too far out; no match */
1353 
1354 	component->loc = pspan->loc;
1355 
1356 	/*
1357 	 * A sudden and significant increase in a pspan's cumulative
1358 	 * pressure indicates the incidence of a new finger
1359 	 * contact. This usually revises the pspan's
1360 	 * centre-of-gravity, and hence the location of any/all
1361 	 * matching stroke component(s). But such a change should
1362 	 * *not* be interpreted as a movement.
1363 	 */
1364 	if (pspan->cum > ((3 * component->cum_pressure) >> 1))
1365 		delta_mickeys = 0;
1366 
1367 	component->cum_pressure = pspan->cum;
1368 	if (pspan->cum > component->max_cum_pressure)
1369 		component->max_cum_pressure = pspan->cum;
1370 
1371 	/*
1372 	 * Disregard the component's movement if its cumulative
1373 	 * pressure drops below a fraction of the maximum; this
1374 	 * fraction is determined based on the stroke's type.
1375 	 */
1376 	if (stroke_type == ATP_STROKE_TOUCH)
1377 		min_pressure = (3 * component->max_cum_pressure) >> 2;
1378 	else
1379 		min_pressure = component->max_cum_pressure >> 2;
1380 	if (component->cum_pressure < min_pressure)
1381 		delta_mickeys = 0;
1382 
1383 	component->delta_mickeys = delta_mickeys;
1384 	return (true);
1385 }
1386 
1387 static void
1388 fg_match_strokes_against_pspans(struct atp_softc *sc, atp_axis axis,
1389     fg_pspan *pspans, u_int n_pspans, u_int repeat_count)
1390 {
1391 	atp_stroke_t *strokep;
1392 	u_int repeat_index = 0;
1393 	u_int i;
1394 
1395 	/* Determine the index of the multi-span. */
1396 	if (repeat_count) {
1397 		for (i = 0; i < n_pspans; i++) {
1398 			if (pspans[i].cum > pspans[repeat_index].cum)
1399 				repeat_index = i;
1400 		}
1401 	}
1402 
1403 	TAILQ_FOREACH(strokep, &sc->sc_stroke_used, entry) {
1404 		if (strokep->components[axis].matched)
1405 			continue; /* skip matched components */
1406 
1407 		for (i = 0; i < n_pspans; i++) {
1408 			if (pspans[i].matched)
1409 				continue; /* skip matched pspans */
1410 
1411 			if (fg_match_stroke_component(
1412 			    &strokep->components[axis], &pspans[i],
1413 			    strokep->type)) {
1414 
1415 				/* There is a match. */
1416 				strokep->components[axis].matched = true;
1417 
1418 				/* Take care to repeat at the multi-span. */
1419 				if ((repeat_count > 0) && (i == repeat_index))
1420 					repeat_count--;
1421 				else
1422 					pspans[i].matched = true;
1423 
1424 				break; /* skip to the next strokep */
1425 			}
1426 		} /* loop over pspans */
1427 	} /* loop over strokes */
1428 }
1429 
1430 static boolean_t
1431 wsp_match_strokes_against_fingers(struct atp_softc *sc,
1432     wsp_finger_t *fingers, u_int n_fingers)
1433 {
1434 	boolean_t movement = false;
1435 	atp_stroke_t *strokep;
1436 	u_int i;
1437 
1438 	/* reset the matched status for all strokes */
1439 	TAILQ_FOREACH(strokep, &sc->sc_stroke_used, entry)
1440 		strokep->matched = false;
1441 
1442 	for (i = 0; i != n_fingers; i++) {
1443 		u_int least_distance_sq = WSP_MAX_ALLOWED_MATCH_DISTANCE_SQ;
1444 		atp_stroke_t *strokep_best = NULL;
1445 
1446 		TAILQ_FOREACH(strokep, &sc->sc_stroke_used, entry) {
1447 			int instantaneous_dx;
1448 			int instantaneous_dy;
1449 			u_int d_squared;
1450 
1451 			if (strokep->matched)
1452 				continue;
1453 
1454 			instantaneous_dx = fingers[i].x - strokep->x;
1455 			instantaneous_dy = fingers[i].y - strokep->y;
1456 
1457 			/* skip strokes which are far away */
1458 			d_squared =
1459 			    (instantaneous_dx * instantaneous_dx) +
1460 			    (instantaneous_dy * instantaneous_dy);
1461 
1462 			if (d_squared < least_distance_sq) {
1463 				least_distance_sq = d_squared;
1464 				strokep_best = strokep;
1465 			}
1466 		}
1467 
1468 		strokep = strokep_best;
1469 
1470 		if (strokep != NULL) {
1471 			fingers[i].matched = true;
1472 
1473 			strokep->matched          = true;
1474 			strokep->instantaneous_dx = fingers[i].x - strokep->x;
1475 			strokep->instantaneous_dy = fingers[i].y - strokep->y;
1476 			strokep->x                = fingers[i].x;
1477 			strokep->y                = fingers[i].y;
1478 
1479 			atp_advance_stroke_state(sc, strokep, &movement);
1480 		}
1481 	}
1482 	return (movement);
1483 }
1484 
1485 /*
1486  * Update strokes by matching against current pressure-spans.
1487  * Return true if any movement is detected.
1488  */
1489 static boolean_t
1490 fg_update_strokes(struct atp_softc *sc, fg_pspan *pspans_x,
1491     u_int n_xpspans, fg_pspan *pspans_y, u_int n_ypspans)
1492 {
1493 	atp_stroke_t *strokep;
1494 	atp_stroke_t *strokep_next;
1495 	boolean_t movement = false;
1496 	u_int repeat_count = 0;
1497 	u_int i;
1498 	u_int j;
1499 
1500 	/* Reset X and Y components of all strokes as unmatched. */
1501 	TAILQ_FOREACH(strokep, &sc->sc_stroke_used, entry) {
1502 		strokep->components[X].matched = false;
1503 		strokep->components[Y].matched = false;
1504 	}
1505 
1506 	/*
1507 	 * Usually, the X and Y pspans come in pairs (the common case
1508 	 * being a single pair). It is possible, however, that
1509 	 * multiple contacts resolve to a single pspan along an
1510 	 * axis, as illustrated in the following:
1511 	 *
1512 	 *   F = finger-contact
1513 	 *
1514 	 *                pspan  pspan
1515 	 *        +-----------------------+
1516 	 *        |         .      .      |
1517 	 *        |         .      .      |
1518 	 *        |         .      .      |
1519 	 *        |         .      .      |
1520 	 *  pspan |.........F......F      |
1521 	 *        |                       |
1522 	 *        |                       |
1523 	 *        |                       |
1524 	 *        +-----------------------+
1525 	 *
1526 	 *
1527 	 * The above case can be detected by a difference in the
1528 	 * number of X and Y pspans. When this happens, X and Y pspans
1529 	 * aren't easy to pair or match against strokes.
1530 	 *
1531 	 * When X and Y pspans differ in number, the axis with the
1532 	 * smaller number of pspans is regarded as having a repeating
1533 	 * pspan (or a multi-pspan)--in the above illustration, the
1534 	 * Y-axis has a repeating pspan. Our approach is to try to
1535 	 * match the multi-pspan repeatedly against strokes. The
1536 	 * difference between the number of X and Y pspans gives us a
1537 	 * crude repeat_count for matching multi-pspans--i.e. the
1538 	 * multi-pspan along the Y axis (above) has a repeat_count of 1.
1539 	 */
1540 	repeat_count = abs(n_xpspans - n_ypspans);
1541 
1542 	fg_match_strokes_against_pspans(sc, X, pspans_x, n_xpspans,
1543 	    (((repeat_count != 0) && ((n_xpspans < n_ypspans))) ?
1544 		repeat_count : 0));
1545 	fg_match_strokes_against_pspans(sc, Y, pspans_y, n_ypspans,
1546 	    (((repeat_count != 0) && (n_ypspans < n_xpspans)) ?
1547 		repeat_count : 0));
1548 
1549 	/* Update the state of strokes based on the above pspan matches. */
1550 	TAILQ_FOREACH_SAFE(strokep, &sc->sc_stroke_used, entry, strokep_next) {
1551 
1552 		if (strokep->components[X].matched &&
1553 		    strokep->components[Y].matched) {
1554 			strokep->matched = true;
1555 			strokep->instantaneous_dx =
1556 			    strokep->components[X].delta_mickeys;
1557 			strokep->instantaneous_dy =
1558 			    strokep->components[Y].delta_mickeys;
1559 			atp_advance_stroke_state(sc, strokep, &movement);
1560 		} else {
1561 			/*
1562 			 * At least one component of this stroke
1563 			 * didn't match against current pspans;
1564 			 * terminate it.
1565 			 */
1566 			atp_terminate_stroke(sc, strokep);
1567 		}
1568 	}
1569 
1570 	/* Add new strokes for pairs of unmatched pspans */
1571 	for (i = 0; i < n_xpspans; i++) {
1572 		if (pspans_x[i].matched == false) break;
1573 	}
1574 	for (j = 0; j < n_ypspans; j++) {
1575 		if (pspans_y[j].matched == false) break;
1576 	}
1577 	if ((i < n_xpspans) && (j < n_ypspans)) {
1578 #ifdef USB_DEBUG
1579 		if (atp_debug >= ATP_LLEVEL_INFO) {
1580 			printf("unmatched pspans:");
1581 			for (; i < n_xpspans; i++) {
1582 				if (pspans_x[i].matched)
1583 					continue;
1584 				printf(" X:[loc:%u,cum:%u]",
1585 				    pspans_x[i].loc, pspans_x[i].cum);
1586 			}
1587 			for (; j < n_ypspans; j++) {
1588 				if (pspans_y[j].matched)
1589 					continue;
1590 				printf(" Y:[loc:%u,cum:%u]",
1591 				    pspans_y[j].loc, pspans_y[j].cum);
1592 			}
1593 			printf("\n");
1594 		}
1595 #endif /* USB_DEBUG */
1596 		if ((n_xpspans == 1) && (n_ypspans == 1))
1597 			/* The common case of a single pair of new pspans. */
1598 			fg_add_stroke(sc, &pspans_x[0], &pspans_y[0]);
1599 		else
1600 			fg_add_new_strokes(sc, pspans_x, n_xpspans,
1601 			    pspans_y, n_ypspans);
1602 	}
1603 
1604 #ifdef USB_DEBUG
1605 	if (atp_debug >= ATP_LLEVEL_INFO) {
1606 		TAILQ_FOREACH(strokep, &sc->sc_stroke_used, entry) {
1607 			printf(" %s%clc:%u,dm:%d,cum:%d,max:%d,%c"
1608 			    ",%clc:%u,dm:%d,cum:%d,max:%d,%c",
1609 			    (strokep->flags & ATSF_ZOMBIE) ? "zomb:" : "",
1610 			    (strokep->type == ATP_STROKE_TOUCH) ? '[' : '<',
1611 			    strokep->components[X].loc,
1612 			    strokep->components[X].delta_mickeys,
1613 			    strokep->components[X].cum_pressure,
1614 			    strokep->components[X].max_cum_pressure,
1615 			    (strokep->type == ATP_STROKE_TOUCH) ? ']' : '>',
1616 			    (strokep->type == ATP_STROKE_TOUCH) ? '[' : '<',
1617 			    strokep->components[Y].loc,
1618 			    strokep->components[Y].delta_mickeys,
1619 			    strokep->components[Y].cum_pressure,
1620 			    strokep->components[Y].max_cum_pressure,
1621 			    (strokep->type == ATP_STROKE_TOUCH) ? ']' : '>');
1622 		}
1623 		if (TAILQ_FIRST(&sc->sc_stroke_used) != NULL)
1624 			printf("\n");
1625 	}
1626 #endif /* USB_DEBUG */
1627 	return (movement);
1628 }
1629 
1630 /*
1631  * Update strokes by matching against current pressure-spans.
1632  * Return true if any movement is detected.
1633  */
1634 static boolean_t
1635 wsp_update_strokes(struct atp_softc *sc, wsp_finger_t *fingers, u_int n_fingers)
1636 {
1637 	boolean_t movement = false;
1638 	atp_stroke_t *strokep_next;
1639 	atp_stroke_t *strokep;
1640 	u_int i;
1641 
1642 	if (sc->sc_n_strokes > 0) {
1643 		movement = wsp_match_strokes_against_fingers(
1644 		    sc, fingers, n_fingers);
1645 
1646 		/* handle zombie strokes */
1647 		TAILQ_FOREACH_SAFE(strokep, &sc->sc_stroke_used, entry, strokep_next) {
1648 			if (strokep->matched)
1649 				continue;
1650 			atp_terminate_stroke(sc, strokep);
1651 		}
1652 	}
1653 
1654 	/* initialize unmatched fingers as strokes */
1655 	for (i = 0; i != n_fingers; i++) {
1656 		if (fingers[i].matched)
1657 			continue;
1658 
1659 		wsp_add_stroke(sc, fingers + i);
1660 	}
1661 	return (movement);
1662 }
1663 
1664 /* Initialize a stroke using a pressure-span. */
1665 static void
1666 fg_add_stroke(struct atp_softc *sc, const fg_pspan *pspan_x,
1667     const fg_pspan *pspan_y)
1668 {
1669 	atp_stroke_t *strokep;
1670 
1671 	strokep = atp_alloc_stroke(sc);
1672 	if (strokep == NULL)
1673 		return;
1674 
1675 	/*
1676 	 * Strokes begin as potential touches. If a stroke survives
1677 	 * longer than a threshold, or if it records significant
1678 	 * cumulative movement, then it is considered a 'slide'.
1679 	 */
1680 	strokep->type    = ATP_STROKE_TOUCH;
1681 	strokep->matched = false;
1682 	microtime(&strokep->ctime);
1683 	strokep->age     = 1;		/* number of interrupts */
1684 	strokep->x       = pspan_x->loc;
1685 	strokep->y       = pspan_y->loc;
1686 
1687 	strokep->components[X].loc              = pspan_x->loc;
1688 	strokep->components[X].cum_pressure     = pspan_x->cum;
1689 	strokep->components[X].max_cum_pressure = pspan_x->cum;
1690 	strokep->components[X].matched          = true;
1691 
1692 	strokep->components[Y].loc              = pspan_y->loc;
1693 	strokep->components[Y].cum_pressure     = pspan_y->cum;
1694 	strokep->components[Y].max_cum_pressure = pspan_y->cum;
1695 	strokep->components[Y].matched          = true;
1696 
1697 	if (sc->sc_n_strokes > 1) {
1698 		/* Reset double-tap-n-drag if we have more than one strokes. */
1699 		sc->sc_state &= ~ATP_DOUBLE_TAP_DRAG;
1700 	}
1701 
1702 	DPRINTFN(ATP_LLEVEL_INFO, "[%u,%u], time: %u,%ld\n",
1703 	    strokep->components[X].loc,
1704 	    strokep->components[Y].loc,
1705 	    (u_int)strokep->ctime.tv_sec,
1706 	    (unsigned long int)strokep->ctime.tv_usec);
1707 }
1708 
1709 static void
1710 fg_add_new_strokes(struct atp_softc *sc, fg_pspan *pspans_x,
1711     u_int n_xpspans, fg_pspan *pspans_y, u_int n_ypspans)
1712 {
1713 	fg_pspan spans[2][FG_MAX_PSPANS_PER_AXIS];
1714 	u_int nspans[2];
1715 	u_int i;
1716 	u_int j;
1717 
1718 	/* Copy unmatched pspans into the local arrays. */
1719 	for (i = 0, nspans[X] = 0; i < n_xpspans; i++) {
1720 		if (pspans_x[i].matched == false) {
1721 			spans[X][nspans[X]] = pspans_x[i];
1722 			nspans[X]++;
1723 		}
1724 	}
1725 	for (j = 0, nspans[Y] = 0; j < n_ypspans; j++) {
1726 		if (pspans_y[j].matched == false) {
1727 			spans[Y][nspans[Y]] = pspans_y[j];
1728 			nspans[Y]++;
1729 		}
1730 	}
1731 
1732 	if (nspans[X] == nspans[Y]) {
1733 		/* Create new strokes from pairs of unmatched pspans */
1734 		for (i = 0, j = 0; (i < nspans[X]) && (j < nspans[Y]); i++, j++)
1735 			fg_add_stroke(sc, &spans[X][i], &spans[Y][j]);
1736 	} else {
1737 		u_int    cum = 0;
1738 		atp_axis repeat_axis;      /* axis with multi-pspans */
1739 		u_int    repeat_count;     /* repeat count for the multi-pspan*/
1740 		u_int    repeat_index = 0; /* index of the multi-span */
1741 
1742 		repeat_axis  = (nspans[X] > nspans[Y]) ? Y : X;
1743 		repeat_count = abs(nspans[X] - nspans[Y]);
1744 		for (i = 0; i < nspans[repeat_axis]; i++) {
1745 			if (spans[repeat_axis][i].cum > cum) {
1746 				repeat_index = i;
1747 				cum = spans[repeat_axis][i].cum;
1748 			}
1749 		}
1750 
1751 		/* Create new strokes from pairs of unmatched pspans */
1752 		i = 0, j = 0;
1753 		for (; (i < nspans[X]) && (j < nspans[Y]); i++, j++) {
1754 			fg_add_stroke(sc, &spans[X][i], &spans[Y][j]);
1755 
1756 			/* Take care to repeat at the multi-pspan. */
1757 			if (repeat_count > 0) {
1758 				if ((repeat_axis == X) &&
1759 				    (repeat_index == i)) {
1760 					i--; /* counter loop increment */
1761 					repeat_count--;
1762 				} else if ((repeat_axis == Y) &&
1763 				    (repeat_index == j)) {
1764 					j--; /* counter loop increment */
1765 					repeat_count--;
1766 				}
1767 			}
1768 		}
1769 	}
1770 }
1771 
1772 /* Initialize a stroke from an unmatched finger. */
1773 static void
1774 wsp_add_stroke(struct atp_softc *sc, const wsp_finger_t *fingerp)
1775 {
1776 	atp_stroke_t *strokep;
1777 
1778 	strokep = atp_alloc_stroke(sc);
1779 	if (strokep == NULL)
1780 		return;
1781 
1782 	/*
1783 	 * Strokes begin as potential touches. If a stroke survives
1784 	 * longer than a threshold, or if it records significant
1785 	 * cumulative movement, then it is considered a 'slide'.
1786 	 */
1787 	strokep->type    = ATP_STROKE_TOUCH;
1788 	strokep->matched = true;
1789 	microtime(&strokep->ctime);
1790 	strokep->age = 1;	/* number of interrupts */
1791 	strokep->x = fingerp->x;
1792 	strokep->y = fingerp->y;
1793 
1794 	/* Reset double-tap-n-drag if we have more than one strokes. */
1795 	if (sc->sc_n_strokes > 1)
1796 		sc->sc_state &= ~ATP_DOUBLE_TAP_DRAG;
1797 
1798 	DPRINTFN(ATP_LLEVEL_INFO, "[%d,%d]\n", strokep->x, strokep->y);
1799 }
1800 
1801 static void
1802 atp_advance_stroke_state(struct atp_softc *sc, atp_stroke_t *strokep,
1803     boolean_t *movementp)
1804 {
1805 	/* Revitalize stroke if it had previously been marked as a zombie. */
1806 	if (strokep->flags & ATSF_ZOMBIE)
1807 		strokep->flags &= ~ATSF_ZOMBIE;
1808 
1809 	strokep->age++;
1810 	if (strokep->age <= atp_stroke_maturity_threshold) {
1811 		/* Avoid noise from immature strokes. */
1812 		strokep->instantaneous_dx = 0;
1813 		strokep->instantaneous_dy = 0;
1814 	}
1815 
1816 	if (atp_compute_stroke_movement(strokep))
1817 		*movementp = true;
1818 
1819 	if (strokep->type != ATP_STROKE_TOUCH)
1820 		return;
1821 
1822 	/* Convert touch strokes to slides upon detecting movement or age. */
1823 	if ((abs(strokep->cum_movement_x) > atp_slide_min_movement) ||
1824 	    (abs(strokep->cum_movement_y) > atp_slide_min_movement))
1825 		atp_convert_to_slide(sc, strokep);
1826 	else {
1827 		/* Compute the stroke's age. */
1828 		struct timeval tdiff;
1829 		getmicrotime(&tdiff);
1830 		if (timevalcmp(&tdiff, &strokep->ctime, >)) {
1831 			timevalsub(&tdiff, &strokep->ctime);
1832 
1833 			if ((tdiff.tv_sec > (atp_touch_timeout / 1000000)) ||
1834 			    ((tdiff.tv_sec == (atp_touch_timeout / 1000000)) &&
1835 			     (tdiff.tv_usec >= (atp_touch_timeout % 1000000))))
1836 				atp_convert_to_slide(sc, strokep);
1837 		}
1838 	}
1839 }
1840 
1841 static boolean_t
1842 atp_stroke_has_small_movement(const atp_stroke_t *strokep)
1843 {
1844 	return (((u_int)abs(strokep->instantaneous_dx) <=
1845 		 atp_small_movement_threshold) &&
1846 		((u_int)abs(strokep->instantaneous_dy) <=
1847 		 atp_small_movement_threshold));
1848 }
1849 
1850 /*
1851  * Accumulate instantaneous changes into the stroke's 'pending' bucket; if
1852  * the aggregate exceeds the small_movement_threshold, then retain
1853  * instantaneous changes for later.
1854  */
1855 static void
1856 atp_update_pending_mickeys(atp_stroke_t *strokep)
1857 {
1858 	/* accumulate instantaneous movement */
1859 	strokep->pending_dx += strokep->instantaneous_dx;
1860 	strokep->pending_dy += strokep->instantaneous_dy;
1861 
1862 #define UPDATE_INSTANTANEOUS_AND_PENDING(I, P)                          \
1863 	if (abs((P)) <= atp_small_movement_threshold)                   \
1864 		(I) = 0; /* clobber small movement */                   \
1865 	else {                                                          \
1866 		if ((I) > 0) {                                          \
1867 			/*                                              \
1868 			 * Round up instantaneous movement to the nearest \
1869 			 * ceiling. This helps preserve small mickey    \
1870 			 * movements from being lost in following scaling \
1871 			 * operation.                                   \
1872 			 */                                             \
1873 			(I) = (((I) + (atp_mickeys_scale_factor - 1)) / \
1874 			       atp_mickeys_scale_factor) *              \
1875 			      atp_mickeys_scale_factor;                 \
1876 									\
1877 			/*                                              \
1878 			 * Deduct the rounded mickeys from pending mickeys. \
1879 			 * Note: we multiply by 2 to offset the previous \
1880 			 * accumulation of instantaneous movement into  \
1881 			 * pending.                                     \
1882 			 */                                             \
1883 			(P) -= ((I) << 1);                              \
1884 									\
1885 			/* truncate pending to 0 if it becomes negative. */ \
1886 			(P) = imax((P), 0);                             \
1887 		} else {                                                \
1888 			/*                                              \
1889 			 * Round down instantaneous movement to the nearest \
1890 			 * ceiling. This helps preserve small mickey    \
1891 			 * movements from being lost in following scaling \
1892 			 * operation.                                   \
1893 			 */                                             \
1894 			(I) = (((I) - (atp_mickeys_scale_factor - 1)) / \
1895 			       atp_mickeys_scale_factor) *              \
1896 			      atp_mickeys_scale_factor;                 \
1897 									\
1898 			/*                                              \
1899 			 * Deduct the rounded mickeys from pending mickeys. \
1900 			 * Note: we multiply by 2 to offset the previous \
1901 			 * accumulation of instantaneous movement into  \
1902 			 * pending.                                     \
1903 			 */                                             \
1904 			(P) -= ((I) << 1);                              \
1905 									\
1906 			/* truncate pending to 0 if it becomes positive. */ \
1907 			(P) = imin((P), 0);                             \
1908 		}                                                       \
1909 	}
1910 
1911 	UPDATE_INSTANTANEOUS_AND_PENDING(strokep->instantaneous_dx,
1912 	    strokep->pending_dx);
1913 	UPDATE_INSTANTANEOUS_AND_PENDING(strokep->instantaneous_dy,
1914 	    strokep->pending_dy);
1915 }
1916 
1917 /*
1918  * Compute a smoothened value for the stroke's movement from
1919  * instantaneous changes in the X and Y components.
1920  */
1921 static boolean_t
1922 atp_compute_stroke_movement(atp_stroke_t *strokep)
1923 {
1924 	/*
1925 	 * Short movements are added first to the 'pending' bucket,
1926 	 * and then acted upon only when their aggregate exceeds a
1927 	 * threshold. This has the effect of filtering away movement
1928 	 * noise.
1929 	 */
1930 	if (atp_stroke_has_small_movement(strokep))
1931 		atp_update_pending_mickeys(strokep);
1932 	else {                /* large movement */
1933 		/* clear away any pending mickeys if there are large movements*/
1934 		strokep->pending_dx = 0;
1935 		strokep->pending_dy = 0;
1936 	}
1937 
1938 	/* scale movement */
1939 	strokep->movement_dx = (strokep->instantaneous_dx) /
1940 	    (int)atp_mickeys_scale_factor;
1941 	strokep->movement_dy = (strokep->instantaneous_dy) /
1942 	    (int)atp_mickeys_scale_factor;
1943 
1944 	if ((abs(strokep->instantaneous_dx) >= ATP_FAST_MOVEMENT_TRESHOLD) ||
1945 	    (abs(strokep->instantaneous_dy) >= ATP_FAST_MOVEMENT_TRESHOLD)) {
1946 		strokep->movement_dx <<= 1;
1947 		strokep->movement_dy <<= 1;
1948 	}
1949 
1950 	strokep->cum_movement_x += strokep->movement_dx;
1951 	strokep->cum_movement_y += strokep->movement_dy;
1952 
1953 	return ((strokep->movement_dx != 0) || (strokep->movement_dy != 0));
1954 }
1955 
1956 /*
1957  * Terminate a stroke. Aside from immature strokes, a slide or touch is
1958  * retained as a zombies so as to reap all their termination siblings
1959  * together; this helps establish the number of fingers involved at the
1960  * end of a multi-touch gesture.
1961  */
1962 static void
1963 atp_terminate_stroke(struct atp_softc *sc, atp_stroke_t *strokep)
1964 {
1965 	if (strokep->flags & ATSF_ZOMBIE)
1966 		return;
1967 
1968 	/* Drop immature strokes rightaway. */
1969 	if (strokep->age <= atp_stroke_maturity_threshold) {
1970 		atp_free_stroke(sc, strokep);
1971 		return;
1972 	}
1973 
1974 	strokep->flags |= ATSF_ZOMBIE;
1975 	sc->sc_state |= ATP_ZOMBIES_EXIST;
1976 
1977 	callout_reset(&sc->sc_callout, ATP_ZOMBIE_STROKE_REAP_INTERVAL,
1978 	    atp_reap_sibling_zombies, sc);
1979 
1980 	/*
1981 	 * Reset the double-click-n-drag at the termination of any
1982 	 * slide stroke.
1983 	 */
1984 	if (strokep->type == ATP_STROKE_SLIDE)
1985 		sc->sc_state &= ~ATP_DOUBLE_TAP_DRAG;
1986 }
1987 
1988 static boolean_t
1989 atp_is_horizontal_scroll(const atp_stroke_t *strokep)
1990 {
1991 	if (abs(strokep->cum_movement_x) < atp_slide_min_movement)
1992 		return (false);
1993 	if (strokep->cum_movement_y == 0)
1994 		return (true);
1995 	return (abs(strokep->cum_movement_x / strokep->cum_movement_y) >= 4);
1996 }
1997 
1998 static boolean_t
1999 atp_is_vertical_scroll(const atp_stroke_t *strokep)
2000 {
2001 	if (abs(strokep->cum_movement_y) < atp_slide_min_movement)
2002 		return (false);
2003 	if (strokep->cum_movement_x == 0)
2004 		return (true);
2005 	return (abs(strokep->cum_movement_y / strokep->cum_movement_x) >= 4);
2006 }
2007 
2008 static void
2009 atp_reap_sibling_zombies(void *arg)
2010 {
2011 	struct atp_softc *sc = (struct atp_softc *)arg;
2012 	u_int8_t n_touches_reaped = 0;
2013 	u_int8_t n_slides_reaped = 0;
2014 	u_int8_t n_horizontal_scrolls = 0;
2015 	u_int8_t n_vertical_scrolls = 0;
2016 	int horizontal_scroll = 0;
2017 	int vertical_scroll = 0;
2018 	atp_stroke_t *strokep;
2019 	atp_stroke_t *strokep_next;
2020 
2021 	DPRINTFN(ATP_LLEVEL_INFO, "\n");
2022 
2023 	TAILQ_FOREACH_SAFE(strokep, &sc->sc_stroke_used, entry, strokep_next) {
2024 		if ((strokep->flags & ATSF_ZOMBIE) == 0)
2025 			continue;
2026 
2027 		if (strokep->type == ATP_STROKE_TOUCH) {
2028 			n_touches_reaped++;
2029 		} else {
2030 			n_slides_reaped++;
2031 
2032 			if (atp_is_horizontal_scroll(strokep)) {
2033 				n_horizontal_scrolls++;
2034 				horizontal_scroll += strokep->cum_movement_x;
2035 			} else if (atp_is_vertical_scroll(strokep)) {
2036 				n_vertical_scrolls++;
2037 				vertical_scroll +=  strokep->cum_movement_y;
2038 			}
2039 		}
2040 
2041 		atp_free_stroke(sc, strokep);
2042 	}
2043 
2044 	DPRINTFN(ATP_LLEVEL_INFO, "reaped %u zombies\n",
2045 	    n_touches_reaped + n_slides_reaped);
2046 	sc->sc_state &= ~ATP_ZOMBIES_EXIST;
2047 
2048 	/* No further processing necessary if physical button is depressed. */
2049 	if (sc->sc_ibtn != 0)
2050 		return;
2051 
2052 	if ((n_touches_reaped == 0) && (n_slides_reaped == 0))
2053 		return;
2054 
2055 	/* Add a pair of virtual button events (button-down and button-up) if
2056 	 * the physical button isn't pressed. */
2057 	if (n_touches_reaped != 0) {
2058 		if (n_touches_reaped < atp_tap_minimum)
2059 			return;
2060 
2061 		switch (n_touches_reaped) {
2062 		case 1:
2063 			atp_add_to_queue(sc, 0, 0, 0, MOUSE_BUTTON1DOWN);
2064 			microtime(&sc->sc_touch_reap_time); /* remember this time */
2065 			break;
2066 		case 2:
2067 			atp_add_to_queue(sc, 0, 0, 0, MOUSE_BUTTON3DOWN);
2068 			break;
2069 		case 3:
2070 			atp_add_to_queue(sc, 0, 0, 0, MOUSE_BUTTON2DOWN);
2071 			break;
2072 		default:
2073 			/* we handle taps of only up to 3 fingers */
2074 			return;
2075 		}
2076 		atp_add_to_queue(sc, 0, 0, 0, 0); /* button release */
2077 
2078 	} else if ((n_slides_reaped == 2) && (n_horizontal_scrolls == 2)) {
2079 		if (horizontal_scroll < 0)
2080 			atp_add_to_queue(sc, 0, 0, 0, MOUSE_BUTTON4DOWN);
2081 		else
2082 			atp_add_to_queue(sc, 0, 0, 0, MOUSE_BUTTON5DOWN);
2083 		atp_add_to_queue(sc, 0, 0, 0, 0); /* button release */
2084 	}
2085 }
2086 
2087 /* Switch a given touch stroke to being a slide. */
2088 static void
2089 atp_convert_to_slide(struct atp_softc *sc, atp_stroke_t *strokep)
2090 {
2091 	strokep->type = ATP_STROKE_SLIDE;
2092 
2093 	/* Are we at the beginning of a double-click-n-drag? */
2094 	if ((sc->sc_n_strokes == 1) &&
2095 	    ((sc->sc_state & ATP_ZOMBIES_EXIST) == 0) &&
2096 	    timevalcmp(&strokep->ctime, &sc->sc_touch_reap_time, >)) {
2097 		struct timeval delta;
2098 		struct timeval window = {
2099 			atp_double_tap_threshold / 1000000,
2100 			atp_double_tap_threshold % 1000000
2101 		};
2102 
2103 		delta = strokep->ctime;
2104 		timevalsub(&delta, &sc->sc_touch_reap_time);
2105 		if (timevalcmp(&delta, &window, <=))
2106 			sc->sc_state |= ATP_DOUBLE_TAP_DRAG;
2107 	}
2108 }
2109 
2110 static void
2111 atp_reset_buf(struct atp_softc *sc)
2112 {
2113 	/* reset read queue */
2114 	usb_fifo_reset(sc->sc_fifo.fp[USB_FIFO_RX]);
2115 }
2116 
2117 static void
2118 atp_add_to_queue(struct atp_softc *sc, int dx, int dy, int dz,
2119     uint32_t buttons_in)
2120 {
2121 	uint32_t buttons_out;
2122 	uint8_t  buf[8];
2123 
2124 	dx = imin(dx,  254); dx = imax(dx, -256);
2125 	dy = imin(dy,  254); dy = imax(dy, -256);
2126 	dz = imin(dz,  126); dz = imax(dz, -128);
2127 
2128 	buttons_out = MOUSE_MSC_BUTTONS;
2129 	if (buttons_in & MOUSE_BUTTON1DOWN)
2130 		buttons_out &= ~MOUSE_MSC_BUTTON1UP;
2131 	else if (buttons_in & MOUSE_BUTTON2DOWN)
2132 		buttons_out &= ~MOUSE_MSC_BUTTON2UP;
2133 	else if (buttons_in & MOUSE_BUTTON3DOWN)
2134 		buttons_out &= ~MOUSE_MSC_BUTTON3UP;
2135 
2136 	DPRINTFN(ATP_LLEVEL_INFO, "dx=%d, dy=%d, buttons=%x\n",
2137 	    dx, dy, buttons_out);
2138 
2139 	/* Encode the mouse data in standard format; refer to mouse(4) */
2140 	buf[0] = sc->sc_mode.syncmask[1];
2141 	buf[0] |= buttons_out;
2142 	buf[1] = dx >> 1;
2143 	buf[2] = dy >> 1;
2144 	buf[3] = dx - (dx >> 1);
2145 	buf[4] = dy - (dy >> 1);
2146 	/* Encode extra bytes for level 1 */
2147 	if (sc->sc_mode.level == 1) {
2148 		buf[5] = dz >> 1;
2149 		buf[6] = dz - (dz >> 1);
2150 		buf[7] = (((~buttons_in) >> 3) & MOUSE_SYS_EXTBUTTONS);
2151 	}
2152 
2153 	usb_fifo_put_data_linear(sc->sc_fifo.fp[USB_FIFO_RX], buf,
2154 	    sc->sc_mode.packetsize, 1);
2155 }
2156 
2157 static int
2158 atp_probe(device_t self)
2159 {
2160 	struct usb_attach_arg *uaa = device_get_ivars(self);
2161 
2162 	if (uaa->usb_mode != USB_MODE_HOST)
2163 		return (ENXIO);
2164 
2165 	if (uaa->info.bInterfaceClass != UICLASS_HID)
2166 		return (ENXIO);
2167 	/*
2168 	 * Note: for some reason, the check
2169 	 * (uaa->info.bInterfaceProtocol == UIPROTO_MOUSE) doesn't hold true
2170 	 * for wellspring trackpads, so we've removed it from the common path.
2171 	 */
2172 
2173 	if ((usbd_lookup_id_by_uaa(fg_devs, sizeof(fg_devs), uaa)) == 0)
2174 		return ((uaa->info.bInterfaceProtocol == UIPROTO_MOUSE) ?
2175 			0 : ENXIO);
2176 
2177 	if ((usbd_lookup_id_by_uaa(wsp_devs, sizeof(wsp_devs), uaa)) == 0)
2178 		if (uaa->info.bIfaceIndex == WELLSPRING_INTERFACE_INDEX)
2179 			return (0);
2180 
2181 	return (ENXIO);
2182 }
2183 
2184 static int
2185 atp_attach(device_t dev)
2186 {
2187 	struct atp_softc      *sc  = device_get_softc(dev);
2188 	struct usb_attach_arg *uaa = device_get_ivars(dev);
2189 	usb_error_t            err;
2190 	void *descriptor_ptr = NULL;
2191 	uint16_t descriptor_len;
2192 	unsigned long di;
2193 
2194 	DPRINTFN(ATP_LLEVEL_INFO, "sc=%p\n", sc);
2195 
2196 	sc->sc_dev        = dev;
2197 	sc->sc_usb_device = uaa->device;
2198 
2199 	/* Get HID descriptor */
2200 	if (usbd_req_get_hid_desc(uaa->device, NULL, &descriptor_ptr,
2201 	    &descriptor_len, M_TEMP, uaa->info.bIfaceIndex) !=
2202 	    USB_ERR_NORMAL_COMPLETION)
2203 		return (ENXIO);
2204 
2205 	/* Get HID report descriptor length */
2206 	sc->sc_expected_sensor_data_len = hid_report_size(descriptor_ptr,
2207 	    descriptor_len, hid_input, NULL);
2208 	free(descriptor_ptr, M_TEMP);
2209 
2210 	if ((sc->sc_expected_sensor_data_len <= 0) ||
2211 	    (sc->sc_expected_sensor_data_len > ATP_SENSOR_DATA_BUF_MAX)) {
2212 		DPRINTF("atp_attach: datalength invalid or too large: %d\n",
2213 			sc->sc_expected_sensor_data_len);
2214 		return (ENXIO);
2215 	}
2216 
2217 	/*
2218 	 * By default the touchpad behaves like an HID device, sending
2219 	 * packets with reportID = 2. Such reports contain only
2220 	 * limited information--they encode movement deltas and button
2221 	 * events,--but do not include data from the pressure
2222 	 * sensors. The device input mode can be switched from HID
2223 	 * reports to raw sensor data using vendor-specific USB
2224 	 * control commands.
2225 	 */
2226 	if ((err = atp_set_device_mode(sc, RAW_SENSOR_MODE)) != 0) {
2227 		DPRINTF("failed to set mode to 'RAW_SENSOR' (%d)\n", err);
2228 		return (ENXIO);
2229 	}
2230 
2231 	mtx_init(&sc->sc_mutex, "atpmtx", NULL, MTX_DEF | MTX_RECURSE);
2232 
2233 	di = USB_GET_DRIVER_INFO(uaa);
2234 
2235 	sc->sc_family = DECODE_FAMILY_FROM_DRIVER_INFO(di);
2236 
2237 	switch(sc->sc_family) {
2238 	case TRACKPAD_FAMILY_FOUNTAIN_GEYSER:
2239 		sc->sc_params =
2240 		    &fg_dev_params[DECODE_PRODUCT_FROM_DRIVER_INFO(di)];
2241 		sc->sensor_data_interpreter = fg_interpret_sensor_data;
2242 		break;
2243 	case TRACKPAD_FAMILY_WELLSPRING:
2244 		sc->sc_params =
2245 		    &wsp_dev_params[DECODE_PRODUCT_FROM_DRIVER_INFO(di)];
2246 		sc->sensor_data_interpreter = wsp_interpret_sensor_data;
2247 		break;
2248 	default:
2249 		goto detach;
2250 	}
2251 
2252 	err = usbd_transfer_setup(uaa->device,
2253 	    &uaa->info.bIfaceIndex, sc->sc_xfer, atp_xfer_config,
2254 	    ATP_N_TRANSFER, sc, &sc->sc_mutex);
2255 	if (err) {
2256 		DPRINTF("error=%s\n", usbd_errstr(err));
2257 		goto detach;
2258 	}
2259 
2260 	if (usb_fifo_attach(sc->sc_usb_device, sc, &sc->sc_mutex,
2261 	    &atp_fifo_methods, &sc->sc_fifo,
2262 	    device_get_unit(dev), -1, uaa->info.bIfaceIndex,
2263 	    UID_ROOT, GID_OPERATOR, 0644)) {
2264 		goto detach;
2265 	}
2266 
2267 	device_set_usb_desc(dev);
2268 
2269 	sc->sc_hw.buttons       = 3;
2270 	sc->sc_hw.iftype        = MOUSE_IF_USB;
2271 	sc->sc_hw.type          = MOUSE_PAD;
2272 	sc->sc_hw.model         = MOUSE_MODEL_GENERIC;
2273 	sc->sc_hw.hwid          = 0;
2274 	sc->sc_mode.protocol    = MOUSE_PROTO_MSC;
2275 	sc->sc_mode.rate        = -1;
2276 	sc->sc_mode.resolution  = MOUSE_RES_UNKNOWN;
2277 	sc->sc_mode.packetsize  = MOUSE_MSC_PACKETSIZE;
2278 	sc->sc_mode.syncmask[0] = MOUSE_MSC_SYNCMASK;
2279 	sc->sc_mode.syncmask[1] = MOUSE_MSC_SYNC;
2280 	sc->sc_mode.accelfactor = 0;
2281 	sc->sc_mode.level       = 0;
2282 
2283 	sc->sc_state            = 0;
2284 	sc->sc_ibtn             = 0;
2285 
2286 	callout_init_mtx(&sc->sc_callout, &sc->sc_mutex, 0);
2287 
2288 	return (0);
2289 
2290 detach:
2291 	atp_detach(dev);
2292 	return (ENOMEM);
2293 }
2294 
2295 static int
2296 atp_detach(device_t dev)
2297 {
2298 	struct atp_softc *sc;
2299 
2300 	sc = device_get_softc(dev);
2301 	atp_set_device_mode(sc, HID_MODE);
2302 
2303 	mtx_lock(&sc->sc_mutex);
2304 	callout_drain(&sc->sc_callout);
2305 	if (sc->sc_state & ATP_ENABLED)
2306 		atp_disable(sc);
2307 	mtx_unlock(&sc->sc_mutex);
2308 
2309 	usb_fifo_detach(&sc->sc_fifo);
2310 
2311 	usbd_transfer_unsetup(sc->sc_xfer, ATP_N_TRANSFER);
2312 
2313 	mtx_destroy(&sc->sc_mutex);
2314 
2315 	return (0);
2316 }
2317 
2318 static void
2319 atp_intr(struct usb_xfer *xfer, usb_error_t error)
2320 {
2321 	struct atp_softc      *sc = usbd_xfer_softc(xfer);
2322 	struct usb_page_cache *pc;
2323 	int len;
2324 
2325 	usbd_xfer_status(xfer, &len, NULL, NULL, NULL);
2326 
2327 	switch (USB_GET_STATE(xfer)) {
2328 	case USB_ST_TRANSFERRED:
2329 		pc = usbd_xfer_get_frame(xfer, 0);
2330 		usbd_copy_out(pc, 0, sc->sc_sensor_data, len);
2331 		if (len < sc->sc_expected_sensor_data_len) {
2332 			/* make sure we don't process old data */
2333 			memset(sc->sc_sensor_data + len, 0,
2334 			    sc->sc_expected_sensor_data_len - len);
2335 		}
2336 
2337 		sc->sc_status.flags &= ~(MOUSE_STDBUTTONSCHANGED |
2338 		    MOUSE_POSCHANGED);
2339 		sc->sc_status.obutton = sc->sc_status.button;
2340 
2341 		(sc->sensor_data_interpreter)(sc, len);
2342 
2343 		if (sc->sc_status.button != 0) {
2344 			/* Reset DOUBLE_TAP_N_DRAG if the button is pressed. */
2345 			sc->sc_state &= ~ATP_DOUBLE_TAP_DRAG;
2346 		} else if (sc->sc_state & ATP_DOUBLE_TAP_DRAG) {
2347 			/* Assume a button-press with DOUBLE_TAP_N_DRAG. */
2348 			sc->sc_status.button = MOUSE_BUTTON1DOWN;
2349 		}
2350 
2351 		sc->sc_status.flags |=
2352 		    sc->sc_status.button ^ sc->sc_status.obutton;
2353 		if (sc->sc_status.flags & MOUSE_STDBUTTONSCHANGED) {
2354 		    DPRINTFN(ATP_LLEVEL_INFO, "button %s\n",
2355 			((sc->sc_status.button & MOUSE_BUTTON1DOWN) ?
2356 			"pressed" : "released"));
2357 		}
2358 
2359 		if (sc->sc_status.flags & (MOUSE_POSCHANGED |
2360 		    MOUSE_STDBUTTONSCHANGED)) {
2361 
2362 			atp_stroke_t *strokep;
2363 			u_int8_t n_movements = 0;
2364 			int dx = 0;
2365 			int dy = 0;
2366 			int dz = 0;
2367 
2368 			TAILQ_FOREACH(strokep, &sc->sc_stroke_used, entry) {
2369 				if (strokep->flags & ATSF_ZOMBIE)
2370 					continue;
2371 
2372 				dx += strokep->movement_dx;
2373 				dy += strokep->movement_dy;
2374 				if (strokep->movement_dx ||
2375 				    strokep->movement_dy)
2376 					n_movements++;
2377 			}
2378 
2379 			/* average movement if multiple strokes record motion.*/
2380 			if (n_movements > 1) {
2381 				dx /= (int)n_movements;
2382 				dy /= (int)n_movements;
2383 			}
2384 
2385 			/* detect multi-finger vertical scrolls */
2386 			if (n_movements >= 2) {
2387 				boolean_t all_vertical_scrolls = true;
2388 				TAILQ_FOREACH(strokep, &sc->sc_stroke_used, entry) {
2389 					if (strokep->flags & ATSF_ZOMBIE)
2390 						continue;
2391 
2392 					if (!atp_is_vertical_scroll(strokep))
2393 						all_vertical_scrolls = false;
2394 				}
2395 				if (all_vertical_scrolls) {
2396 					dz = dy;
2397 					dy = dx = 0;
2398 				}
2399 			}
2400 
2401 			sc->sc_status.dx += dx;
2402 			sc->sc_status.dy += dy;
2403 			sc->sc_status.dz += dz;
2404 			atp_add_to_queue(sc, dx, -dy, -dz, sc->sc_status.button);
2405 		}
2406 
2407 	case USB_ST_SETUP:
2408 	tr_setup:
2409 		/* check if we can put more data into the FIFO */
2410 		if (usb_fifo_put_bytes_max(sc->sc_fifo.fp[USB_FIFO_RX]) != 0) {
2411 			usbd_xfer_set_frame_len(xfer, 0,
2412 			    sc->sc_expected_sensor_data_len);
2413 			usbd_transfer_submit(xfer);
2414 		}
2415 		break;
2416 
2417 	default:                        /* Error */
2418 		if (error != USB_ERR_CANCELLED) {
2419 			/* try clear stall first */
2420 			usbd_xfer_set_stall(xfer);
2421 			goto tr_setup;
2422 		}
2423 		break;
2424 	}
2425 }
2426 
2427 static void
2428 atp_start_read(struct usb_fifo *fifo)
2429 {
2430 	struct atp_softc *sc = usb_fifo_softc(fifo);
2431 	int rate;
2432 
2433 	/* Check if we should override the default polling interval */
2434 	rate = sc->sc_pollrate;
2435 	/* Range check rate */
2436 	if (rate > 1000)
2437 		rate = 1000;
2438 	/* Check for set rate */
2439 	if ((rate > 0) && (sc->sc_xfer[ATP_INTR_DT] != NULL)) {
2440 		/* Stop current transfer, if any */
2441 		usbd_transfer_stop(sc->sc_xfer[ATP_INTR_DT]);
2442 		/* Set new interval */
2443 		usbd_xfer_set_interval(sc->sc_xfer[ATP_INTR_DT], 1000 / rate);
2444 		/* Only set pollrate once */
2445 		sc->sc_pollrate = 0;
2446 	}
2447 
2448 	usbd_transfer_start(sc->sc_xfer[ATP_INTR_DT]);
2449 }
2450 
2451 static void
2452 atp_stop_read(struct usb_fifo *fifo)
2453 {
2454 	struct atp_softc *sc = usb_fifo_softc(fifo);
2455 	usbd_transfer_stop(sc->sc_xfer[ATP_INTR_DT]);
2456 }
2457 
2458 static int
2459 atp_open(struct usb_fifo *fifo, int fflags)
2460 {
2461 	struct atp_softc *sc = usb_fifo_softc(fifo);
2462 
2463 	/* check for duplicate open, should not happen */
2464 	if (sc->sc_fflags & fflags)
2465 		return (EBUSY);
2466 
2467 	/* check for first open */
2468 	if (sc->sc_fflags == 0) {
2469 		int rc;
2470 		if ((rc = atp_enable(sc)) != 0)
2471 			return (rc);
2472 	}
2473 
2474 	if (fflags & FREAD) {
2475 		if (usb_fifo_alloc_buffer(fifo,
2476 		    ATP_FIFO_BUF_SIZE, ATP_FIFO_QUEUE_MAXLEN)) {
2477 			return (ENOMEM);
2478 		}
2479 	}
2480 
2481 	sc->sc_fflags |= (fflags & (FREAD | FWRITE));
2482 	return (0);
2483 }
2484 
2485 static void
2486 atp_close(struct usb_fifo *fifo, int fflags)
2487 {
2488 	struct atp_softc *sc = usb_fifo_softc(fifo);
2489 	if (fflags & FREAD)
2490 		usb_fifo_free_buffer(fifo);
2491 
2492 	sc->sc_fflags &= ~(fflags & (FREAD | FWRITE));
2493 	if (sc->sc_fflags == 0) {
2494 		atp_disable(sc);
2495 	}
2496 }
2497 
2498 static int
2499 atp_ioctl(struct usb_fifo *fifo, u_long cmd, void *addr, int fflags)
2500 {
2501 	struct atp_softc *sc = usb_fifo_softc(fifo);
2502 	mousemode_t mode;
2503 	int error = 0;
2504 
2505 	mtx_lock(&sc->sc_mutex);
2506 
2507 	switch(cmd) {
2508 	case MOUSE_GETHWINFO:
2509 		*(mousehw_t *)addr = sc->sc_hw;
2510 		break;
2511 	case MOUSE_GETMODE:
2512 		*(mousemode_t *)addr = sc->sc_mode;
2513 		break;
2514 	case MOUSE_SETMODE:
2515 		mode = *(mousemode_t *)addr;
2516 
2517 		if (mode.level == -1)
2518 			/* Don't change the current setting */
2519 			;
2520 		else if ((mode.level < 0) || (mode.level > 1)) {
2521 			error = EINVAL;
2522 			break;
2523 		}
2524 		sc->sc_mode.level = mode.level;
2525 		sc->sc_pollrate   = mode.rate;
2526 		sc->sc_hw.buttons = 3;
2527 
2528 		if (sc->sc_mode.level == 0) {
2529 			sc->sc_mode.protocol    = MOUSE_PROTO_MSC;
2530 			sc->sc_mode.packetsize  = MOUSE_MSC_PACKETSIZE;
2531 			sc->sc_mode.syncmask[0] = MOUSE_MSC_SYNCMASK;
2532 			sc->sc_mode.syncmask[1] = MOUSE_MSC_SYNC;
2533 		} else if (sc->sc_mode.level == 1) {
2534 			sc->sc_mode.protocol    = MOUSE_PROTO_SYSMOUSE;
2535 			sc->sc_mode.packetsize  = MOUSE_SYS_PACKETSIZE;
2536 			sc->sc_mode.syncmask[0] = MOUSE_SYS_SYNCMASK;
2537 			sc->sc_mode.syncmask[1] = MOUSE_SYS_SYNC;
2538 		}
2539 		atp_reset_buf(sc);
2540 		break;
2541 	case MOUSE_GETLEVEL:
2542 		*(int *)addr = sc->sc_mode.level;
2543 		break;
2544 	case MOUSE_SETLEVEL:
2545 		if ((*(int *)addr < 0) || (*(int *)addr > 1)) {
2546 			error = EINVAL;
2547 			break;
2548 		}
2549 		sc->sc_mode.level = *(int *)addr;
2550 		sc->sc_hw.buttons = 3;
2551 
2552 		if (sc->sc_mode.level == 0) {
2553 			sc->sc_mode.protocol    = MOUSE_PROTO_MSC;
2554 			sc->sc_mode.packetsize  = MOUSE_MSC_PACKETSIZE;
2555 			sc->sc_mode.syncmask[0] = MOUSE_MSC_SYNCMASK;
2556 			sc->sc_mode.syncmask[1] = MOUSE_MSC_SYNC;
2557 		} else if (sc->sc_mode.level == 1) {
2558 			sc->sc_mode.protocol    = MOUSE_PROTO_SYSMOUSE;
2559 			sc->sc_mode.packetsize  = MOUSE_SYS_PACKETSIZE;
2560 			sc->sc_mode.syncmask[0] = MOUSE_SYS_SYNCMASK;
2561 			sc->sc_mode.syncmask[1] = MOUSE_SYS_SYNC;
2562 		}
2563 		atp_reset_buf(sc);
2564 		break;
2565 	case MOUSE_GETSTATUS: {
2566 		mousestatus_t *status = (mousestatus_t *)addr;
2567 
2568 		*status = sc->sc_status;
2569 		sc->sc_status.obutton = sc->sc_status.button;
2570 		sc->sc_status.button  = 0;
2571 		sc->sc_status.dx      = 0;
2572 		sc->sc_status.dy      = 0;
2573 		sc->sc_status.dz      = 0;
2574 
2575 		if (status->dx || status->dy || status->dz)
2576 			status->flags |= MOUSE_POSCHANGED;
2577 		if (status->button != status->obutton)
2578 			status->flags |= MOUSE_BUTTONSCHANGED;
2579 		break;
2580 	}
2581 
2582 	default:
2583 		error = ENOTTY;
2584 		break;
2585 	}
2586 
2587 	mtx_unlock(&sc->sc_mutex);
2588 	return (error);
2589 }
2590 
2591 static int
2592 atp_sysctl_scale_factor_handler(SYSCTL_HANDLER_ARGS)
2593 {
2594 	int error;
2595 	u_int tmp;
2596 
2597 	tmp = atp_mickeys_scale_factor;
2598 	error = sysctl_handle_int(oidp, &tmp, 0, req);
2599 	if (error != 0 || req->newptr == NULL)
2600 		return (error);
2601 
2602 	if (tmp == atp_mickeys_scale_factor)
2603 		return (0);     /* no change */
2604 	if ((tmp == 0) || (tmp > (10 * ATP_SCALE_FACTOR)))
2605 		return (EINVAL);
2606 
2607 	atp_mickeys_scale_factor = tmp;
2608 	DPRINTFN(ATP_LLEVEL_INFO, "%s: resetting mickeys_scale_factor to %u\n",
2609 	    ATP_DRIVER_NAME, tmp);
2610 
2611 	return (0);
2612 }
2613 
2614 static devclass_t atp_devclass;
2615 
2616 static device_method_t atp_methods[] = {
2617 	DEVMETHOD(device_probe,  atp_probe),
2618 	DEVMETHOD(device_attach, atp_attach),
2619 	DEVMETHOD(device_detach, atp_detach),
2620 
2621 	DEVMETHOD_END
2622 };
2623 
2624 static driver_t atp_driver = {
2625 	.name    = ATP_DRIVER_NAME,
2626 	.methods = atp_methods,
2627 	.size    = sizeof(struct atp_softc)
2628 };
2629 
2630 DRIVER_MODULE(atp, uhub, atp_driver, atp_devclass, NULL, 0);
2631 MODULE_DEPEND(atp, usb, 1, 1, 1);
2632 MODULE_VERSION(atp, 1);
2633