xref: /linux/drivers/input/mouse/appletouch.c (revision f879306834818ebd1722a4372079610cdd466fec)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Apple USB Touchpad (for post-February 2005 PowerBooks and MacBooks) driver
4  *
5  * Copyright (C) 2001-2004 Greg Kroah-Hartman (greg@kroah.com)
6  * Copyright (C) 2005-2008 Johannes Berg (johannes@sipsolutions.net)
7  * Copyright (C) 2005-2008 Stelian Pop (stelian@popies.net)
8  * Copyright (C) 2005      Frank Arnold (frank@scirocco-5v-turbo.de)
9  * Copyright (C) 2005      Peter Osterlund (petero2@telia.com)
10  * Copyright (C) 2005      Michael Hanselmann (linux-kernel@hansmi.ch)
11  * Copyright (C) 2006      Nicolas Boichat (nicolas@boichat.ch)
12  * Copyright (C) 2007-2008 Sven Anders (anders@anduras.de)
13  *
14  * Thanks to Alex Harper <basilisk@foobox.net> for his inputs.
15  */
16 
17 #include <linux/kernel.h>
18 #include <linux/errno.h>
19 #include <linux/slab.h>
20 #include <linux/module.h>
21 #include <linux/usb/input.h>
22 
23 /*
24  * Note: We try to keep the touchpad aspect ratio while still doing only
25  * simple arithmetics:
26  *	0 <= x <= (xsensors - 1) * xfact
27  *	0 <= y <= (ysensors - 1) * yfact
28  */
29 struct atp_info {
30 	int xsensors;				/* number of X sensors */
31 	int xsensors_17;			/* 17" models have more sensors */
32 	int ysensors;				/* number of Y sensors */
33 	int xfact;				/* X multiplication factor */
34 	int yfact;				/* Y multiplication factor */
35 	int datalen;				/* size of USB transfers */
36 	void (*callback)(struct urb *);		/* callback function */
37 	int fuzz;				/* fuzz touchpad generates */
38 };
39 
40 static void atp_complete_geyser_1_2(struct urb *urb);
41 static void atp_complete_geyser_3_4(struct urb *urb);
42 
43 static const struct atp_info fountain_info = {
44 	.xsensors	= 16,
45 	.xsensors_17	= 26,
46 	.ysensors	= 16,
47 	.xfact		= 64,
48 	.yfact		= 43,
49 	.datalen	= 81,
50 	.callback	= atp_complete_geyser_1_2,
51 	.fuzz		= 16,
52 };
53 
54 static const struct atp_info geyser1_info = {
55 	.xsensors	= 16,
56 	.xsensors_17	= 26,
57 	.ysensors	= 16,
58 	.xfact		= 64,
59 	.yfact		= 43,
60 	.datalen	= 81,
61 	.callback	= atp_complete_geyser_1_2,
62 	.fuzz		= 16,
63 };
64 
65 static const struct atp_info geyser2_info = {
66 	.xsensors	= 15,
67 	.xsensors_17	= 20,
68 	.ysensors	= 9,
69 	.xfact		= 64,
70 	.yfact		= 43,
71 	.datalen	= 64,
72 	.callback	= atp_complete_geyser_1_2,
73 	.fuzz		= 0,
74 };
75 
76 static const struct atp_info geyser3_info = {
77 	.xsensors	= 20,
78 	.ysensors	= 10,
79 	.xfact		= 64,
80 	.yfact		= 64,
81 	.datalen	= 64,
82 	.callback	= atp_complete_geyser_3_4,
83 	.fuzz		= 0,
84 };
85 
86 static const struct atp_info geyser4_info = {
87 	.xsensors	= 20,
88 	.ysensors	= 10,
89 	.xfact		= 64,
90 	.yfact		= 64,
91 	.datalen	= 64,
92 	.callback	= atp_complete_geyser_3_4,
93 	.fuzz		= 0,
94 };
95 
96 #define ATP_DEVICE(prod, info)					\
97 {								\
98 	.match_flags = USB_DEVICE_ID_MATCH_DEVICE |		\
99 		       USB_DEVICE_ID_MATCH_INT_CLASS |		\
100 		       USB_DEVICE_ID_MATCH_INT_PROTOCOL,	\
101 	.idVendor = 0x05ac, /* Apple */				\
102 	.idProduct = (prod),					\
103 	.bInterfaceClass = 0x03,				\
104 	.bInterfaceProtocol = 0x02,				\
105 	.driver_info = (unsigned long) &info,			\
106 }
107 
108 /*
109  * Table of devices (Product IDs) that work with this driver.
110  * (The names come from Info.plist in AppleUSBTrackpad.kext,
111  *  According to Info.plist Geyser IV is the same as Geyser III.)
112  */
113 
114 static const struct usb_device_id atp_table[] = {
115 	/* PowerBooks Feb 2005, iBooks G4 */
116 	ATP_DEVICE(0x020e, fountain_info),	/* FOUNTAIN ANSI */
117 	ATP_DEVICE(0x020f, fountain_info),	/* FOUNTAIN ISO */
118 	ATP_DEVICE(0x030a, fountain_info),	/* FOUNTAIN TP ONLY */
119 	ATP_DEVICE(0x030b, geyser1_info),	/* GEYSER 1 TP ONLY */
120 
121 	/* PowerBooks Oct 2005 */
122 	ATP_DEVICE(0x0214, geyser2_info),	/* GEYSER 2 ANSI */
123 	ATP_DEVICE(0x0215, geyser2_info),	/* GEYSER 2 ISO */
124 	ATP_DEVICE(0x0216, geyser2_info),	/* GEYSER 2 JIS */
125 
126 	/* Core Duo MacBook & MacBook Pro */
127 	ATP_DEVICE(0x0217, geyser3_info),	/* GEYSER 3 ANSI */
128 	ATP_DEVICE(0x0218, geyser3_info),	/* GEYSER 3 ISO */
129 	ATP_DEVICE(0x0219, geyser3_info),	/* GEYSER 3 JIS */
130 
131 	/* Core2 Duo MacBook & MacBook Pro */
132 	ATP_DEVICE(0x021a, geyser4_info),	/* GEYSER 4 ANSI */
133 	ATP_DEVICE(0x021b, geyser4_info),	/* GEYSER 4 ISO */
134 	ATP_DEVICE(0x021c, geyser4_info),	/* GEYSER 4 JIS */
135 
136 	/* Core2 Duo MacBook3,1 */
137 	ATP_DEVICE(0x0229, geyser4_info),	/* GEYSER 4 HF ANSI */
138 	ATP_DEVICE(0x022a, geyser4_info),	/* GEYSER 4 HF ISO */
139 	ATP_DEVICE(0x022b, geyser4_info),	/* GEYSER 4 HF JIS */
140 
141 	/* Terminating entry */
142 	{ }
143 };
144 MODULE_DEVICE_TABLE(usb, atp_table);
145 
146 /* maximum number of sensors */
147 #define ATP_XSENSORS	26
148 #define ATP_YSENSORS	16
149 
150 /*
151  * The largest possible bank of sensors with additional buffer of 4 extra values
152  * on either side, for an array of smoothed sensor values.
153  */
154 #define ATP_SMOOTHSIZE	34
155 
156 /* maximum pressure this driver will report */
157 #define ATP_PRESSURE	300
158 
159 /*
160  * Threshold for the touchpad sensors. Any change less than ATP_THRESHOLD is
161  * ignored.
162  */
163 #define ATP_THRESHOLD	5
164 
165 /*
166  * How far we'll bitshift our sensor values before averaging them. Mitigates
167  * rounding errors.
168  */
169 #define ATP_SCALE	12
170 
171 /* Geyser initialization constants */
172 #define ATP_GEYSER_MODE_READ_REQUEST_ID		1
173 #define ATP_GEYSER_MODE_WRITE_REQUEST_ID	9
174 #define ATP_GEYSER_MODE_REQUEST_VALUE		0x300
175 #define ATP_GEYSER_MODE_REQUEST_INDEX		0
176 #define ATP_GEYSER_MODE_VENDOR_VALUE		0x04
177 
178 /**
179  * enum atp_status_bits - status bit meanings
180  *
181  * These constants represent the meaning of the status bits.
182  * (only Geyser 3/4)
183  *
184  * @ATP_STATUS_BUTTON: The button was pressed
185  * @ATP_STATUS_BASE_UPDATE: Update of the base values (untouched pad)
186  * @ATP_STATUS_FROM_RESET: Reset previously performed
187  */
188 enum atp_status_bits {
189 	ATP_STATUS_BUTTON	= BIT(0),
190 	ATP_STATUS_BASE_UPDATE	= BIT(2),
191 	ATP_STATUS_FROM_RESET	= BIT(4),
192 };
193 
194 /* Structure to hold all of our device specific stuff */
195 struct atp {
196 	char			phys[64];
197 	struct usb_device	*udev;		/* usb device */
198 	struct usb_interface	*intf;		/* usb interface */
199 	struct urb		*urb;		/* usb request block */
200 	u8			*data;		/* transferred data */
201 	struct input_dev	*input;		/* input dev */
202 	const struct atp_info	*info;		/* touchpad model */
203 	bool			open;
204 	bool			valid;		/* are the samples valid? */
205 	bool			size_detect_done;
206 	bool			overflow_warned;
207 	int			fingers_old;	/* last reported finger count */
208 	int			x_old;		/* last reported x/y, */
209 	int			y_old;		/* used for smoothing */
210 	signed char		xy_cur[ATP_XSENSORS + ATP_YSENSORS];
211 	signed char		xy_old[ATP_XSENSORS + ATP_YSENSORS];
212 	int			xy_acc[ATP_XSENSORS + ATP_YSENSORS];
213 	int			smooth[ATP_SMOOTHSIZE];
214 	int			smooth_tmp[ATP_SMOOTHSIZE];
215 	int			idlecount;	/* number of empty packets */
216 	struct work_struct	work;
217 };
218 
219 #define dbg_dump(msg, tab) \
220 	if (debug > 1) {						\
221 		int __i;						\
222 		printk(KERN_DEBUG "appletouch: %s", msg);		\
223 		for (__i = 0; __i < ATP_XSENSORS + ATP_YSENSORS; __i++)	\
224 			printk(" %02x", tab[__i]);			\
225 		printk("\n");						\
226 	}
227 
228 #define dprintk(format, a...)						\
229 	do {								\
230 		if (debug)						\
231 			printk(KERN_DEBUG format, ##a);			\
232 	} while (0)
233 
234 MODULE_AUTHOR("Johannes Berg");
235 MODULE_AUTHOR("Stelian Pop");
236 MODULE_AUTHOR("Frank Arnold");
237 MODULE_AUTHOR("Michael Hanselmann");
238 MODULE_AUTHOR("Sven Anders");
239 MODULE_DESCRIPTION("Apple PowerBook and MacBook USB touchpad driver");
240 MODULE_LICENSE("GPL");
241 
242 /*
243  * Make the threshold a module parameter
244  */
245 static int threshold = ATP_THRESHOLD;
246 module_param(threshold, int, 0644);
247 MODULE_PARM_DESC(threshold, "Discard any change in data from a sensor"
248 			    " (the trackpad has many of these sensors)"
249 			    " less than this value.");
250 
251 static int debug;
252 module_param(debug, int, 0644);
253 MODULE_PARM_DESC(debug, "Activate debugging output");
254 
255 /*
256  * By default newer Geyser devices send standard USB HID mouse
257  * packets (Report ID 2). This code changes device mode, so it
258  * sends raw sensor reports (Report ID 5).
259  */
260 static int atp_geyser_init(struct atp *dev)
261 {
262 	struct usb_device *udev = dev->udev;
263 	char *data;
264 	int size;
265 	int i;
266 	int ret;
267 
268 	data = kmalloc(8, GFP_KERNEL);
269 	if (!data) {
270 		dev_err(&dev->intf->dev, "Out of memory\n");
271 		return -ENOMEM;
272 	}
273 
274 	size = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
275 			ATP_GEYSER_MODE_READ_REQUEST_ID,
276 			USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
277 			ATP_GEYSER_MODE_REQUEST_VALUE,
278 			ATP_GEYSER_MODE_REQUEST_INDEX, data, 8, 5000);
279 
280 	if (size != 8) {
281 		dprintk("atp_geyser_init: read error\n");
282 		for (i = 0; i < 8; i++)
283 			dprintk("appletouch[%d]: %d\n", i, data[i]);
284 
285 		dev_err(&dev->intf->dev, "Failed to read mode from device.\n");
286 		ret = -EIO;
287 		goto out_free;
288 	}
289 
290 	/* Apply the mode switch */
291 	data[0] = ATP_GEYSER_MODE_VENDOR_VALUE;
292 
293 	size = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
294 			ATP_GEYSER_MODE_WRITE_REQUEST_ID,
295 			USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
296 			ATP_GEYSER_MODE_REQUEST_VALUE,
297 			ATP_GEYSER_MODE_REQUEST_INDEX, data, 8, 5000);
298 
299 	if (size != 8) {
300 		dprintk("atp_geyser_init: write error\n");
301 		for (i = 0; i < 8; i++)
302 			dprintk("appletouch[%d]: %d\n", i, data[i]);
303 
304 		dev_err(&dev->intf->dev, "Failed to request geyser raw mode\n");
305 		ret = -EIO;
306 		goto out_free;
307 	}
308 	ret = 0;
309 out_free:
310 	kfree(data);
311 	return ret;
312 }
313 
314 /*
315  * Reinitialise the device. This usually stops stream of empty packets
316  * coming from it.
317  */
318 static void atp_reinit(struct work_struct *work)
319 {
320 	struct atp *dev = container_of(work, struct atp, work);
321 	int retval;
322 
323 	dprintk("appletouch: putting appletouch to sleep (reinit)\n");
324 	atp_geyser_init(dev);
325 
326 	retval = usb_submit_urb(dev->urb, GFP_ATOMIC);
327 	if (retval)
328 		dev_err(&dev->intf->dev,
329 			"atp_reinit: usb_submit_urb failed with error %d\n",
330 			retval);
331 }
332 
333 static int atp_calculate_abs(struct atp *dev, int offset, int nb_sensors,
334 			     int fact, int *z, int *fingers)
335 {
336 	int i, pass;
337 
338 	/*
339 	 * Use offset to point xy_sensors at the first value in dev->xy_acc
340 	 * for whichever dimension we're looking at this particular go-round.
341 	 */
342 	int *xy_sensors = dev->xy_acc + offset;
343 
344 	/* values to calculate mean */
345 	int pcum = 0, psum = 0;
346 	int is_increasing = 0;
347 
348 	*fingers = 0;
349 
350 	for (i = 0; i < nb_sensors; i++) {
351 		if (xy_sensors[i] < threshold) {
352 			if (is_increasing)
353 				is_increasing = 0;
354 
355 		/*
356 		 * Makes the finger detection more versatile.  For example,
357 		 * two fingers with no gap will be detected.  Also, my
358 		 * tests show it less likely to have intermittent loss
359 		 * of multiple finger readings while moving around (scrolling).
360 		 *
361 		 * Changes the multiple finger detection to counting humps on
362 		 * sensors (transitions from nonincreasing to increasing)
363 		 * instead of counting transitions from low sensors (no
364 		 * finger reading) to high sensors (finger above
365 		 * sensor)
366 		 *
367 		 * - Jason Parekh <jasonparekh@gmail.com>
368 		 */
369 
370 		} else if (i < 1 ||
371 		    (!is_increasing && xy_sensors[i - 1] < xy_sensors[i])) {
372 			(*fingers)++;
373 			is_increasing = 1;
374 		} else if (i > 0 && (xy_sensors[i - 1] - xy_sensors[i] > threshold)) {
375 			is_increasing = 0;
376 		}
377 	}
378 
379 	if (*fingers < 1)     /* No need to continue if no fingers are found. */
380 		return 0;
381 
382 	/*
383 	 * Use a smoothed version of sensor data for movement calculations, to
384 	 * combat noise without needing to rely so heavily on a threshold.
385 	 * This improves tracking.
386 	 *
387 	 * The smoothed array is bigger than the original so that the smoothing
388 	 * doesn't result in edge values being truncated.
389 	 */
390 
391 	memset(dev->smooth, 0, 4 * sizeof(dev->smooth[0]));
392 	/* Pull base values, scaled up to help avoid truncation errors. */
393 	for (i = 0; i < nb_sensors; i++)
394 		dev->smooth[i + 4] = xy_sensors[i] << ATP_SCALE;
395 	memset(&dev->smooth[nb_sensors + 4], 0, 4 * sizeof(dev->smooth[0]));
396 
397 	for (pass = 0; pass < 4; pass++) {
398 		/* Handle edge. */
399 		dev->smooth_tmp[0] = (dev->smooth[0] + dev->smooth[1]) / 2;
400 
401 		/* Average values with neighbors. */
402 		for (i = 1; i < nb_sensors + 7; i++)
403 			dev->smooth_tmp[i] = (dev->smooth[i - 1] +
404 					      dev->smooth[i] * 2 +
405 					      dev->smooth[i + 1]) / 4;
406 
407 		/* Handle other edge. */
408 		dev->smooth_tmp[i] = (dev->smooth[i - 1] + dev->smooth[i]) / 2;
409 
410 		memcpy(dev->smooth, dev->smooth_tmp, sizeof(dev->smooth));
411 	}
412 
413 	for (i = 0; i < nb_sensors + 8; i++) {
414 		/*
415 		 * Skip values if they're small enough to be truncated to 0
416 		 * by scale. Mostly noise.
417 		 */
418 		if ((dev->smooth[i] >> ATP_SCALE) > 0) {
419 			pcum += dev->smooth[i] * i;
420 			psum += dev->smooth[i];
421 		}
422 	}
423 
424 	if (psum > 0) {
425 		*z = psum >> ATP_SCALE;        /* Scale down pressure output. */
426 		return pcum * fact / psum;
427 	}
428 
429 	return 0;
430 }
431 
432 static inline void atp_report_fingers(struct input_dev *input, int fingers)
433 {
434 	input_report_key(input, BTN_TOOL_FINGER, fingers == 1);
435 	input_report_key(input, BTN_TOOL_DOUBLETAP, fingers == 2);
436 	input_report_key(input, BTN_TOOL_TRIPLETAP, fingers > 2);
437 }
438 
439 /* Check URB status and for correct length of data package */
440 
441 #define ATP_URB_STATUS_SUCCESS		0
442 #define ATP_URB_STATUS_ERROR		1
443 #define ATP_URB_STATUS_ERROR_FATAL	2
444 
445 static int atp_status_check(struct urb *urb)
446 {
447 	struct atp *dev = urb->context;
448 	struct usb_interface *intf = dev->intf;
449 
450 	switch (urb->status) {
451 	case 0:
452 		/* success */
453 		break;
454 	case -EOVERFLOW:
455 		if (!dev->overflow_warned) {
456 			dev_warn(&intf->dev,
457 				"appletouch: OVERFLOW with data length %d, actual length is %d\n",
458 				dev->info->datalen, dev->urb->actual_length);
459 			dev->overflow_warned = true;
460 		}
461 		fallthrough;
462 	case -ECONNRESET:
463 	case -ENOENT:
464 	case -ESHUTDOWN:
465 		/* This urb is terminated, clean up */
466 		dev_dbg(&intf->dev,
467 			"atp_complete: urb shutting down with status: %d\n",
468 			urb->status);
469 		return ATP_URB_STATUS_ERROR_FATAL;
470 
471 	default:
472 		dev_dbg(&intf->dev,
473 			"atp_complete: nonzero urb status received: %d\n",
474 			urb->status);
475 		return ATP_URB_STATUS_ERROR;
476 	}
477 
478 	/* drop incomplete datasets */
479 	if (dev->urb->actual_length != dev->info->datalen) {
480 		dprintk("appletouch: incomplete data package"
481 			" (first byte: %d, length: %d).\n",
482 			dev->data[0], dev->urb->actual_length);
483 		return ATP_URB_STATUS_ERROR;
484 	}
485 
486 	return ATP_URB_STATUS_SUCCESS;
487 }
488 
489 static void atp_detect_size(struct atp *dev)
490 {
491 	int i;
492 
493 	/* 17" Powerbooks have extra X sensors */
494 	for (i = dev->info->xsensors; i < ATP_XSENSORS; i++) {
495 		if (dev->xy_cur[i]) {
496 
497 			dev_info(&dev->intf->dev,
498 				"appletouch: 17\" model detected.\n");
499 
500 			input_set_abs_params(dev->input, ABS_X, 0,
501 					     (dev->info->xsensors_17 - 1) *
502 							dev->info->xfact - 1,
503 					     dev->info->fuzz, 0);
504 			break;
505 		}
506 	}
507 }
508 
509 /*
510  * USB interrupt callback functions
511  */
512 
513 /* Interrupt function for older touchpads: FOUNTAIN/GEYSER1/GEYSER2 */
514 
515 static void atp_complete_geyser_1_2(struct urb *urb)
516 {
517 	int x, y, x_z, y_z, x_f, y_f;
518 	int retval, i, j;
519 	int key, fingers;
520 	struct atp *dev = urb->context;
521 	int status = atp_status_check(urb);
522 
523 	if (status == ATP_URB_STATUS_ERROR_FATAL)
524 		return;
525 	else if (status == ATP_URB_STATUS_ERROR)
526 		goto exit;
527 
528 	/* reorder the sensors values */
529 	if (dev->info == &geyser2_info) {
530 		memset(dev->xy_cur, 0, sizeof(dev->xy_cur));
531 
532 		/*
533 		 * The values are laid out like this:
534 		 * Y1, Y2, -, Y3, Y4, -, ..., X1, X2, -, X3, X4, -, ...
535 		 * '-' is an unused value.
536 		 */
537 
538 		/* read X values */
539 		for (i = 0, j = 19; i < 20; i += 2, j += 3) {
540 			dev->xy_cur[i] = dev->data[j];
541 			dev->xy_cur[i + 1] = dev->data[j + 1];
542 		}
543 
544 		/* read Y values */
545 		for (i = 0, j = 1; i < 9; i += 2, j += 3) {
546 			dev->xy_cur[ATP_XSENSORS + i] = dev->data[j];
547 			dev->xy_cur[ATP_XSENSORS + i + 1] = dev->data[j + 1];
548 		}
549 	} else {
550 		for (i = 0; i < 8; i++) {
551 			/* X values */
552 			dev->xy_cur[i +  0] = dev->data[5 * i +  2];
553 			dev->xy_cur[i +  8] = dev->data[5 * i +  4];
554 			dev->xy_cur[i + 16] = dev->data[5 * i + 42];
555 			if (i < 2)
556 				dev->xy_cur[i + 24] = dev->data[5 * i + 44];
557 
558 			/* Y values */
559 			dev->xy_cur[ATP_XSENSORS + i] = dev->data[5 * i +  1];
560 			dev->xy_cur[ATP_XSENSORS + i + 8] = dev->data[5 * i + 3];
561 		}
562 	}
563 
564 	dbg_dump("sample", dev->xy_cur);
565 
566 	if (!dev->valid) {
567 		/* first sample */
568 		dev->valid = true;
569 		dev->x_old = dev->y_old = -1;
570 
571 		/* Store first sample */
572 		memcpy(dev->xy_old, dev->xy_cur, sizeof(dev->xy_old));
573 
574 		/* Perform size detection, if not done already */
575 		if (unlikely(!dev->size_detect_done)) {
576 			atp_detect_size(dev);
577 			dev->size_detect_done = true;
578 			goto exit;
579 		}
580 	}
581 
582 	for (i = 0; i < ATP_XSENSORS + ATP_YSENSORS; i++) {
583 		/* accumulate the change */
584 		signed char change = dev->xy_old[i] - dev->xy_cur[i];
585 		dev->xy_acc[i] -= change;
586 
587 		/* prevent down drifting */
588 		if (dev->xy_acc[i] < 0)
589 			dev->xy_acc[i] = 0;
590 	}
591 
592 	memcpy(dev->xy_old, dev->xy_cur, sizeof(dev->xy_old));
593 
594 	dbg_dump("accumulator", dev->xy_acc);
595 
596 	x = atp_calculate_abs(dev, 0, ATP_XSENSORS,
597 			      dev->info->xfact, &x_z, &x_f);
598 	y = atp_calculate_abs(dev, ATP_XSENSORS, ATP_YSENSORS,
599 			      dev->info->yfact, &y_z, &y_f);
600 	key = dev->data[dev->info->datalen - 1] & ATP_STATUS_BUTTON;
601 
602 	fingers = max(x_f, y_f);
603 
604 	if (x && y && fingers == dev->fingers_old) {
605 		if (dev->x_old != -1) {
606 			x = (dev->x_old * 7 + x) >> 3;
607 			y = (dev->y_old * 7 + y) >> 3;
608 			dev->x_old = x;
609 			dev->y_old = y;
610 
611 			if (debug > 1)
612 				printk(KERN_DEBUG "appletouch: "
613 					"X: %3d Y: %3d Xz: %3d Yz: %3d\n",
614 					x, y, x_z, y_z);
615 
616 			input_report_key(dev->input, BTN_TOUCH, 1);
617 			input_report_abs(dev->input, ABS_X, x);
618 			input_report_abs(dev->input, ABS_Y, y);
619 			input_report_abs(dev->input, ABS_PRESSURE,
620 					 min(ATP_PRESSURE, x_z + y_z));
621 			atp_report_fingers(dev->input, fingers);
622 		}
623 		dev->x_old = x;
624 		dev->y_old = y;
625 
626 	} else if (!x && !y) {
627 
628 		dev->x_old = dev->y_old = -1;
629 		dev->fingers_old = 0;
630 		input_report_key(dev->input, BTN_TOUCH, 0);
631 		input_report_abs(dev->input, ABS_PRESSURE, 0);
632 		atp_report_fingers(dev->input, 0);
633 
634 		/* reset the accumulator on release */
635 		memset(dev->xy_acc, 0, sizeof(dev->xy_acc));
636 	}
637 
638 	if (fingers != dev->fingers_old)
639 		dev->x_old = dev->y_old = -1;
640 	dev->fingers_old = fingers;
641 
642 	input_report_key(dev->input, BTN_LEFT, key);
643 	input_sync(dev->input);
644 
645  exit:
646 	retval = usb_submit_urb(dev->urb, GFP_ATOMIC);
647 	if (retval)
648 		dev_err(&dev->intf->dev,
649 			"atp_complete: usb_submit_urb failed with result %d\n",
650 			retval);
651 }
652 
653 /* Interrupt function for older touchpads: GEYSER3/GEYSER4 */
654 
655 static void atp_complete_geyser_3_4(struct urb *urb)
656 {
657 	int x, y, x_z, y_z, x_f, y_f;
658 	int retval, i, j;
659 	int key, fingers;
660 	struct atp *dev = urb->context;
661 	int status = atp_status_check(urb);
662 
663 	if (status == ATP_URB_STATUS_ERROR_FATAL)
664 		return;
665 	else if (status == ATP_URB_STATUS_ERROR)
666 		goto exit;
667 
668 	/* Reorder the sensors values:
669 	 *
670 	 * The values are laid out like this:
671 	 * -, Y1, Y2, -, Y3, Y4, -, ..., -, X1, X2, -, X3, X4, ...
672 	 * '-' is an unused value.
673 	 */
674 
675 	/* read X values */
676 	for (i = 0, j = 19; i < 20; i += 2, j += 3) {
677 		dev->xy_cur[i] = dev->data[j + 1];
678 		dev->xy_cur[i + 1] = dev->data[j + 2];
679 	}
680 	/* read Y values */
681 	for (i = 0, j = 1; i < 9; i += 2, j += 3) {
682 		dev->xy_cur[ATP_XSENSORS + i] = dev->data[j + 1];
683 		dev->xy_cur[ATP_XSENSORS + i + 1] = dev->data[j + 2];
684 	}
685 
686 	dbg_dump("sample", dev->xy_cur);
687 
688 	/* Just update the base values (i.e. touchpad in untouched state) */
689 	if (dev->data[dev->info->datalen - 1] & ATP_STATUS_BASE_UPDATE) {
690 
691 		dprintk("appletouch: updated base values\n");
692 
693 		memcpy(dev->xy_old, dev->xy_cur, sizeof(dev->xy_old));
694 		goto exit;
695 	}
696 
697 	for (i = 0; i < ATP_XSENSORS + ATP_YSENSORS; i++) {
698 		/* calculate the change */
699 		dev->xy_acc[i] = dev->xy_cur[i] - dev->xy_old[i];
700 
701 		/* this is a round-robin value, so couple with that */
702 		if (dev->xy_acc[i] > 127)
703 			dev->xy_acc[i] -= 256;
704 
705 		if (dev->xy_acc[i] < -127)
706 			dev->xy_acc[i] += 256;
707 
708 		/* prevent down drifting */
709 		if (dev->xy_acc[i] < 0)
710 			dev->xy_acc[i] = 0;
711 	}
712 
713 	dbg_dump("accumulator", dev->xy_acc);
714 
715 	x = atp_calculate_abs(dev, 0, ATP_XSENSORS,
716 			      dev->info->xfact, &x_z, &x_f);
717 	y = atp_calculate_abs(dev, ATP_XSENSORS, ATP_YSENSORS,
718 			      dev->info->yfact, &y_z, &y_f);
719 
720 	key = dev->data[dev->info->datalen - 1] & ATP_STATUS_BUTTON;
721 
722 	fingers = max(x_f, y_f);
723 
724 	if (x && y && fingers == dev->fingers_old) {
725 		if (dev->x_old != -1) {
726 			x = (dev->x_old * 7 + x) >> 3;
727 			y = (dev->y_old * 7 + y) >> 3;
728 			dev->x_old = x;
729 			dev->y_old = y;
730 
731 			if (debug > 1)
732 				printk(KERN_DEBUG "appletouch: X: %3d Y: %3d "
733 				       "Xz: %3d Yz: %3d\n",
734 				       x, y, x_z, y_z);
735 
736 			input_report_key(dev->input, BTN_TOUCH, 1);
737 			input_report_abs(dev->input, ABS_X, x);
738 			input_report_abs(dev->input, ABS_Y, y);
739 			input_report_abs(dev->input, ABS_PRESSURE,
740 					 min(ATP_PRESSURE, x_z + y_z));
741 			atp_report_fingers(dev->input, fingers);
742 		}
743 		dev->x_old = x;
744 		dev->y_old = y;
745 
746 	} else if (!x && !y) {
747 
748 		dev->x_old = dev->y_old = -1;
749 		dev->fingers_old = 0;
750 		input_report_key(dev->input, BTN_TOUCH, 0);
751 		input_report_abs(dev->input, ABS_PRESSURE, 0);
752 		atp_report_fingers(dev->input, 0);
753 
754 		/* reset the accumulator on release */
755 		memset(dev->xy_acc, 0, sizeof(dev->xy_acc));
756 	}
757 
758 	if (fingers != dev->fingers_old)
759 		dev->x_old = dev->y_old = -1;
760 	dev->fingers_old = fingers;
761 
762 	input_report_key(dev->input, BTN_LEFT, key);
763 	input_sync(dev->input);
764 
765 	/*
766 	 * Geysers 3/4 will continue to send packets continually after
767 	 * the first touch unless reinitialised. Do so if it's been
768 	 * idle for a while in order to avoid waking the kernel up
769 	 * several hundred times a second.
770 	 */
771 
772 	/*
773 	 * Button must not be pressed when entering suspend,
774 	 * otherwise we will never release the button.
775 	 */
776 	if (!x && !y && !key) {
777 		dev->idlecount++;
778 		if (dev->idlecount == 10) {
779 			dev->x_old = dev->y_old = -1;
780 			dev->idlecount = 0;
781 			schedule_work(&dev->work);
782 			/* Don't resubmit urb here, wait for reinit */
783 			return;
784 		}
785 	} else
786 		dev->idlecount = 0;
787 
788  exit:
789 	retval = usb_submit_urb(dev->urb, GFP_ATOMIC);
790 	if (retval)
791 		dev_err(&dev->intf->dev,
792 			"atp_complete: usb_submit_urb failed with result %d\n",
793 			retval);
794 }
795 
796 static int atp_open(struct input_dev *input)
797 {
798 	struct atp *dev = input_get_drvdata(input);
799 
800 	if (usb_submit_urb(dev->urb, GFP_KERNEL))
801 		return -EIO;
802 
803 	dev->open = true;
804 	return 0;
805 }
806 
807 static void atp_close(struct input_dev *input)
808 {
809 	struct atp *dev = input_get_drvdata(input);
810 
811 	usb_kill_urb(dev->urb);
812 	cancel_work_sync(&dev->work);
813 	dev->open = false;
814 }
815 
816 static int atp_handle_geyser(struct atp *dev)
817 {
818 	if (dev->info != &fountain_info) {
819 		/* switch to raw sensor mode */
820 		if (atp_geyser_init(dev))
821 			return -EIO;
822 
823 		dev_info(&dev->intf->dev, "Geyser mode initialized.\n");
824 	}
825 
826 	return 0;
827 }
828 
829 static int atp_probe(struct usb_interface *iface,
830 		     const struct usb_device_id *id)
831 {
832 	struct atp *dev;
833 	struct input_dev *input_dev;
834 	struct usb_device *udev = interface_to_usbdev(iface);
835 	struct usb_host_interface *iface_desc;
836 	struct usb_endpoint_descriptor *endpoint;
837 	int int_in_endpointAddr = 0;
838 	int i, error = -ENOMEM;
839 	const struct atp_info *info = (const struct atp_info *)id->driver_info;
840 
841 	/* set up the endpoint information */
842 	/* use only the first interrupt-in endpoint */
843 	iface_desc = iface->cur_altsetting;
844 	for (i = 0; i < iface_desc->desc.bNumEndpoints; i++) {
845 		endpoint = &iface_desc->endpoint[i].desc;
846 		if (!int_in_endpointAddr && usb_endpoint_is_int_in(endpoint)) {
847 			/* we found an interrupt in endpoint */
848 			int_in_endpointAddr = endpoint->bEndpointAddress;
849 			break;
850 		}
851 	}
852 	if (!int_in_endpointAddr) {
853 		dev_err(&iface->dev, "Could not find int-in endpoint\n");
854 		return -EIO;
855 	}
856 
857 	/* allocate memory for our device state and initialize it */
858 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
859 	input_dev = input_allocate_device();
860 	if (!dev || !input_dev) {
861 		dev_err(&iface->dev, "Out of memory\n");
862 		goto err_free_devs;
863 	}
864 
865 	dev->udev = udev;
866 	dev->intf = iface;
867 	dev->input = input_dev;
868 	dev->info = info;
869 	dev->overflow_warned = false;
870 
871 	dev->urb = usb_alloc_urb(0, GFP_KERNEL);
872 	if (!dev->urb)
873 		goto err_free_devs;
874 
875 	dev->data = usb_alloc_coherent(dev->udev, dev->info->datalen, GFP_KERNEL,
876 				       &dev->urb->transfer_dma);
877 	if (!dev->data)
878 		goto err_free_urb;
879 
880 	usb_fill_int_urb(dev->urb, udev,
881 			 usb_rcvintpipe(udev, int_in_endpointAddr),
882 			 dev->data, dev->info->datalen,
883 			 dev->info->callback, dev, 1);
884 
885 	error = atp_handle_geyser(dev);
886 	if (error)
887 		goto err_free_buffer;
888 
889 	usb_make_path(udev, dev->phys, sizeof(dev->phys));
890 	strlcat(dev->phys, "/input0", sizeof(dev->phys));
891 
892 	input_dev->name = "appletouch";
893 	input_dev->phys = dev->phys;
894 	usb_to_input_id(dev->udev, &input_dev->id);
895 	input_dev->dev.parent = &iface->dev;
896 
897 	input_set_drvdata(input_dev, dev);
898 
899 	input_dev->open = atp_open;
900 	input_dev->close = atp_close;
901 
902 	set_bit(EV_ABS, input_dev->evbit);
903 
904 	input_set_abs_params(input_dev, ABS_X, 0,
905 			     (dev->info->xsensors - 1) * dev->info->xfact - 1,
906 			     dev->info->fuzz, 0);
907 	input_set_abs_params(input_dev, ABS_Y, 0,
908 			     (dev->info->ysensors - 1) * dev->info->yfact - 1,
909 			     dev->info->fuzz, 0);
910 	input_set_abs_params(input_dev, ABS_PRESSURE, 0, ATP_PRESSURE, 0, 0);
911 
912 	set_bit(EV_KEY, input_dev->evbit);
913 	set_bit(BTN_TOUCH, input_dev->keybit);
914 	set_bit(BTN_TOOL_FINGER, input_dev->keybit);
915 	set_bit(BTN_TOOL_DOUBLETAP, input_dev->keybit);
916 	set_bit(BTN_TOOL_TRIPLETAP, input_dev->keybit);
917 	set_bit(BTN_LEFT, input_dev->keybit);
918 
919 	INIT_WORK(&dev->work, atp_reinit);
920 
921 	error = input_register_device(dev->input);
922 	if (error)
923 		goto err_free_buffer;
924 
925 	/* save our data pointer in this interface device */
926 	usb_set_intfdata(iface, dev);
927 
928 	return 0;
929 
930  err_free_buffer:
931 	usb_free_coherent(dev->udev, dev->info->datalen,
932 			  dev->data, dev->urb->transfer_dma);
933  err_free_urb:
934 	usb_free_urb(dev->urb);
935  err_free_devs:
936 	usb_set_intfdata(iface, NULL);
937 	kfree(dev);
938 	input_free_device(input_dev);
939 	return error;
940 }
941 
942 static void atp_disconnect(struct usb_interface *iface)
943 {
944 	struct atp *dev = usb_get_intfdata(iface);
945 
946 	usb_set_intfdata(iface, NULL);
947 	if (dev) {
948 		usb_kill_urb(dev->urb);
949 		input_unregister_device(dev->input);
950 		usb_free_coherent(dev->udev, dev->info->datalen,
951 				  dev->data, dev->urb->transfer_dma);
952 		usb_free_urb(dev->urb);
953 		kfree(dev);
954 	}
955 	dev_info(&iface->dev, "input: appletouch disconnected\n");
956 }
957 
958 static int atp_recover(struct atp *dev)
959 {
960 	int error;
961 
962 	error = atp_handle_geyser(dev);
963 	if (error)
964 		return error;
965 
966 	if (dev->open && usb_submit_urb(dev->urb, GFP_KERNEL))
967 		return -EIO;
968 
969 	return 0;
970 }
971 
972 static int atp_suspend(struct usb_interface *iface, pm_message_t message)
973 {
974 	struct atp *dev = usb_get_intfdata(iface);
975 
976 	usb_kill_urb(dev->urb);
977 	return 0;
978 }
979 
980 static int atp_resume(struct usb_interface *iface)
981 {
982 	struct atp *dev = usb_get_intfdata(iface);
983 
984 	if (dev->open && usb_submit_urb(dev->urb, GFP_KERNEL))
985 		return -EIO;
986 
987 	return 0;
988 }
989 
990 static int atp_reset_resume(struct usb_interface *iface)
991 {
992 	struct atp *dev = usb_get_intfdata(iface);
993 
994 	return atp_recover(dev);
995 }
996 
997 static struct usb_driver atp_driver = {
998 	.name		= "appletouch",
999 	.probe		= atp_probe,
1000 	.disconnect	= atp_disconnect,
1001 	.suspend	= atp_suspend,
1002 	.resume		= atp_resume,
1003 	.reset_resume	= atp_reset_resume,
1004 	.id_table	= atp_table,
1005 };
1006 
1007 module_usb_driver(atp_driver);
1008