xref: /openbmc/linux/drivers/input/mouse/appletouch.c (revision e657c18a)
1 /*
2  * Apple USB Touchpad (for post-February 2005 PowerBooks and MacBooks) driver
3  *
4  * Copyright (C) 2001-2004 Greg Kroah-Hartman (greg@kroah.com)
5  * Copyright (C) 2005-2008 Johannes Berg (johannes@sipsolutions.net)
6  * Copyright (C) 2005-2008 Stelian Pop (stelian@popies.net)
7  * Copyright (C) 2005      Frank Arnold (frank@scirocco-5v-turbo.de)
8  * Copyright (C) 2005      Peter Osterlund (petero2@telia.com)
9  * Copyright (C) 2005      Michael Hanselmann (linux-kernel@hansmi.ch)
10  * Copyright (C) 2006      Nicolas Boichat (nicolas@boichat.ch)
11  * Copyright (C) 2007-2008 Sven Anders (anders@anduras.de)
12  *
13  * Thanks to Alex Harper <basilisk@foobox.net> for his inputs.
14  *
15  * This program is free software; you can redistribute it and/or modify
16  * it under the terms of the GNU General Public License as published by
17  * the Free Software Foundation; either version 2 of the License, or
18  * (at your option) any later version.
19  *
20  * This program is distributed in the hope that it will be useful,
21  * but WITHOUT ANY WARRANTY; without even the implied warranty of
22  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
23  * GNU General Public License for more details.
24  *
25  * You should have received a copy of the GNU General Public License
26  * along with this program; if not, write to the Free Software
27  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
28  *
29  */
30 
31 #include <linux/kernel.h>
32 #include <linux/errno.h>
33 #include <linux/slab.h>
34 #include <linux/module.h>
35 #include <linux/usb/input.h>
36 
37 /*
38  * Note: We try to keep the touchpad aspect ratio while still doing only
39  * simple arithmetics:
40  *	0 <= x <= (xsensors - 1) * xfact
41  *	0 <= y <= (ysensors - 1) * yfact
42  */
43 struct atp_info {
44 	int xsensors;				/* number of X sensors */
45 	int xsensors_17;			/* 17" models have more sensors */
46 	int ysensors;				/* number of Y sensors */
47 	int xfact;				/* X multiplication factor */
48 	int yfact;				/* Y multiplication factor */
49 	int datalen;				/* size of USB transfers */
50 	void (*callback)(struct urb *);		/* callback function */
51 	int fuzz;				/* fuzz touchpad generates */
52 };
53 
54 static void atp_complete_geyser_1_2(struct urb *urb);
55 static void atp_complete_geyser_3_4(struct urb *urb);
56 
57 static const struct atp_info fountain_info = {
58 	.xsensors	= 16,
59 	.xsensors_17	= 26,
60 	.ysensors	= 16,
61 	.xfact		= 64,
62 	.yfact		= 43,
63 	.datalen	= 81,
64 	.callback	= atp_complete_geyser_1_2,
65 	.fuzz		= 16,
66 };
67 
68 static const struct atp_info geyser1_info = {
69 	.xsensors	= 16,
70 	.xsensors_17	= 26,
71 	.ysensors	= 16,
72 	.xfact		= 64,
73 	.yfact		= 43,
74 	.datalen	= 81,
75 	.callback	= atp_complete_geyser_1_2,
76 	.fuzz		= 16,
77 };
78 
79 static const struct atp_info geyser2_info = {
80 	.xsensors	= 15,
81 	.xsensors_17	= 20,
82 	.ysensors	= 9,
83 	.xfact		= 64,
84 	.yfact		= 43,
85 	.datalen	= 64,
86 	.callback	= atp_complete_geyser_1_2,
87 	.fuzz		= 0,
88 };
89 
90 static const struct atp_info geyser3_info = {
91 	.xsensors	= 20,
92 	.ysensors	= 10,
93 	.xfact		= 64,
94 	.yfact		= 64,
95 	.datalen	= 64,
96 	.callback	= atp_complete_geyser_3_4,
97 	.fuzz		= 0,
98 };
99 
100 static const struct atp_info geyser4_info = {
101 	.xsensors	= 20,
102 	.ysensors	= 10,
103 	.xfact		= 64,
104 	.yfact		= 64,
105 	.datalen	= 64,
106 	.callback	= atp_complete_geyser_3_4,
107 	.fuzz		= 0,
108 };
109 
110 #define ATP_DEVICE(prod, info)					\
111 {								\
112 	.match_flags = USB_DEVICE_ID_MATCH_DEVICE |		\
113 		       USB_DEVICE_ID_MATCH_INT_CLASS |		\
114 		       USB_DEVICE_ID_MATCH_INT_PROTOCOL,	\
115 	.idVendor = 0x05ac, /* Apple */				\
116 	.idProduct = (prod),					\
117 	.bInterfaceClass = 0x03,				\
118 	.bInterfaceProtocol = 0x02,				\
119 	.driver_info = (unsigned long) &info,			\
120 }
121 
122 /*
123  * Table of devices (Product IDs) that work with this driver.
124  * (The names come from Info.plist in AppleUSBTrackpad.kext,
125  *  According to Info.plist Geyser IV is the same as Geyser III.)
126  */
127 
128 static const struct usb_device_id atp_table[] = {
129 	/* PowerBooks Feb 2005, iBooks G4 */
130 	ATP_DEVICE(0x020e, fountain_info),	/* FOUNTAIN ANSI */
131 	ATP_DEVICE(0x020f, fountain_info),	/* FOUNTAIN ISO */
132 	ATP_DEVICE(0x030a, fountain_info),	/* FOUNTAIN TP ONLY */
133 	ATP_DEVICE(0x030b, geyser1_info),	/* GEYSER 1 TP ONLY */
134 
135 	/* PowerBooks Oct 2005 */
136 	ATP_DEVICE(0x0214, geyser2_info),	/* GEYSER 2 ANSI */
137 	ATP_DEVICE(0x0215, geyser2_info),	/* GEYSER 2 ISO */
138 	ATP_DEVICE(0x0216, geyser2_info),	/* GEYSER 2 JIS */
139 
140 	/* Core Duo MacBook & MacBook Pro */
141 	ATP_DEVICE(0x0217, geyser3_info),	/* GEYSER 3 ANSI */
142 	ATP_DEVICE(0x0218, geyser3_info),	/* GEYSER 3 ISO */
143 	ATP_DEVICE(0x0219, geyser3_info),	/* GEYSER 3 JIS */
144 
145 	/* Core2 Duo MacBook & MacBook Pro */
146 	ATP_DEVICE(0x021a, geyser4_info),	/* GEYSER 4 ANSI */
147 	ATP_DEVICE(0x021b, geyser4_info),	/* GEYSER 4 ISO */
148 	ATP_DEVICE(0x021c, geyser4_info),	/* GEYSER 4 JIS */
149 
150 	/* Core2 Duo MacBook3,1 */
151 	ATP_DEVICE(0x0229, geyser4_info),	/* GEYSER 4 HF ANSI */
152 	ATP_DEVICE(0x022a, geyser4_info),	/* GEYSER 4 HF ISO */
153 	ATP_DEVICE(0x022b, geyser4_info),	/* GEYSER 4 HF JIS */
154 
155 	/* Terminating entry */
156 	{ }
157 };
158 MODULE_DEVICE_TABLE(usb, atp_table);
159 
160 /* maximum number of sensors */
161 #define ATP_XSENSORS	26
162 #define ATP_YSENSORS	16
163 
164 /*
165  * The largest possible bank of sensors with additional buffer of 4 extra values
166  * on either side, for an array of smoothed sensor values.
167  */
168 #define ATP_SMOOTHSIZE	34
169 
170 /* maximum pressure this driver will report */
171 #define ATP_PRESSURE	300
172 
173 /*
174  * Threshold for the touchpad sensors. Any change less than ATP_THRESHOLD is
175  * ignored.
176  */
177 #define ATP_THRESHOLD	5
178 
179 /*
180  * How far we'll bitshift our sensor values before averaging them. Mitigates
181  * rounding errors.
182  */
183 #define ATP_SCALE	12
184 
185 /* Geyser initialization constants */
186 #define ATP_GEYSER_MODE_READ_REQUEST_ID		1
187 #define ATP_GEYSER_MODE_WRITE_REQUEST_ID	9
188 #define ATP_GEYSER_MODE_REQUEST_VALUE		0x300
189 #define ATP_GEYSER_MODE_REQUEST_INDEX		0
190 #define ATP_GEYSER_MODE_VENDOR_VALUE		0x04
191 
192 /**
193  * enum atp_status_bits - status bit meanings
194  *
195  * These constants represent the meaning of the status bits.
196  * (only Geyser 3/4)
197  *
198  * @ATP_STATUS_BUTTON: The button was pressed
199  * @ATP_STATUS_BASE_UPDATE: Update of the base values (untouched pad)
200  * @ATP_STATUS_FROM_RESET: Reset previously performed
201  */
202 enum atp_status_bits {
203 	ATP_STATUS_BUTTON	= BIT(0),
204 	ATP_STATUS_BASE_UPDATE	= BIT(2),
205 	ATP_STATUS_FROM_RESET	= BIT(4),
206 };
207 
208 /* Structure to hold all of our device specific stuff */
209 struct atp {
210 	char			phys[64];
211 	struct usb_device	*udev;		/* usb device */
212 	struct usb_interface	*intf;		/* usb interface */
213 	struct urb		*urb;		/* usb request block */
214 	u8			*data;		/* transferred data */
215 	struct input_dev	*input;		/* input dev */
216 	const struct atp_info	*info;		/* touchpad model */
217 	bool			open;
218 	bool			valid;		/* are the samples valid? */
219 	bool			size_detect_done;
220 	bool			overflow_warned;
221 	int			fingers_old;	/* last reported finger count */
222 	int			x_old;		/* last reported x/y, */
223 	int			y_old;		/* used for smoothing */
224 	signed char		xy_cur[ATP_XSENSORS + ATP_YSENSORS];
225 	signed char		xy_old[ATP_XSENSORS + ATP_YSENSORS];
226 	int			xy_acc[ATP_XSENSORS + ATP_YSENSORS];
227 	int			smooth[ATP_SMOOTHSIZE];
228 	int			smooth_tmp[ATP_SMOOTHSIZE];
229 	int			idlecount;	/* number of empty packets */
230 	struct work_struct	work;
231 };
232 
233 #define dbg_dump(msg, tab) \
234 	if (debug > 1) {						\
235 		int __i;						\
236 		printk(KERN_DEBUG "appletouch: %s", msg);		\
237 		for (__i = 0; __i < ATP_XSENSORS + ATP_YSENSORS; __i++)	\
238 			printk(" %02x", tab[__i]);			\
239 		printk("\n");						\
240 	}
241 
242 #define dprintk(format, a...)						\
243 	do {								\
244 		if (debug)						\
245 			printk(KERN_DEBUG format, ##a);			\
246 	} while (0)
247 
248 MODULE_AUTHOR("Johannes Berg");
249 MODULE_AUTHOR("Stelian Pop");
250 MODULE_AUTHOR("Frank Arnold");
251 MODULE_AUTHOR("Michael Hanselmann");
252 MODULE_AUTHOR("Sven Anders");
253 MODULE_DESCRIPTION("Apple PowerBook and MacBook USB touchpad driver");
254 MODULE_LICENSE("GPL");
255 
256 /*
257  * Make the threshold a module parameter
258  */
259 static int threshold = ATP_THRESHOLD;
260 module_param(threshold, int, 0644);
261 MODULE_PARM_DESC(threshold, "Discard any change in data from a sensor"
262 			    " (the trackpad has many of these sensors)"
263 			    " less than this value.");
264 
265 static int debug;
266 module_param(debug, int, 0644);
267 MODULE_PARM_DESC(debug, "Activate debugging output");
268 
269 /*
270  * By default newer Geyser devices send standard USB HID mouse
271  * packets (Report ID 2). This code changes device mode, so it
272  * sends raw sensor reports (Report ID 5).
273  */
274 static int atp_geyser_init(struct atp *dev)
275 {
276 	struct usb_device *udev = dev->udev;
277 	char *data;
278 	int size;
279 	int i;
280 	int ret;
281 
282 	data = kmalloc(8, GFP_KERNEL);
283 	if (!data) {
284 		dev_err(&dev->intf->dev, "Out of memory\n");
285 		return -ENOMEM;
286 	}
287 
288 	size = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
289 			ATP_GEYSER_MODE_READ_REQUEST_ID,
290 			USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
291 			ATP_GEYSER_MODE_REQUEST_VALUE,
292 			ATP_GEYSER_MODE_REQUEST_INDEX, data, 8, 5000);
293 
294 	if (size != 8) {
295 		dprintk("atp_geyser_init: read error\n");
296 		for (i = 0; i < 8; i++)
297 			dprintk("appletouch[%d]: %d\n", i, data[i]);
298 
299 		dev_err(&dev->intf->dev, "Failed to read mode from device.\n");
300 		ret = -EIO;
301 		goto out_free;
302 	}
303 
304 	/* Apply the mode switch */
305 	data[0] = ATP_GEYSER_MODE_VENDOR_VALUE;
306 
307 	size = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
308 			ATP_GEYSER_MODE_WRITE_REQUEST_ID,
309 			USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
310 			ATP_GEYSER_MODE_REQUEST_VALUE,
311 			ATP_GEYSER_MODE_REQUEST_INDEX, data, 8, 5000);
312 
313 	if (size != 8) {
314 		dprintk("atp_geyser_init: write error\n");
315 		for (i = 0; i < 8; i++)
316 			dprintk("appletouch[%d]: %d\n", i, data[i]);
317 
318 		dev_err(&dev->intf->dev, "Failed to request geyser raw mode\n");
319 		ret = -EIO;
320 		goto out_free;
321 	}
322 	ret = 0;
323 out_free:
324 	kfree(data);
325 	return ret;
326 }
327 
328 /*
329  * Reinitialise the device. This usually stops stream of empty packets
330  * coming from it.
331  */
332 static void atp_reinit(struct work_struct *work)
333 {
334 	struct atp *dev = container_of(work, struct atp, work);
335 	int retval;
336 
337 	dprintk("appletouch: putting appletouch to sleep (reinit)\n");
338 	atp_geyser_init(dev);
339 
340 	retval = usb_submit_urb(dev->urb, GFP_ATOMIC);
341 	if (retval)
342 		dev_err(&dev->intf->dev,
343 			"atp_reinit: usb_submit_urb failed with error %d\n",
344 			retval);
345 }
346 
347 static int atp_calculate_abs(struct atp *dev, int offset, int nb_sensors,
348 			     int fact, int *z, int *fingers)
349 {
350 	int i, pass;
351 
352 	/*
353 	 * Use offset to point xy_sensors at the first value in dev->xy_acc
354 	 * for whichever dimension we're looking at this particular go-round.
355 	 */
356 	int *xy_sensors = dev->xy_acc + offset;
357 
358 	/* values to calculate mean */
359 	int pcum = 0, psum = 0;
360 	int is_increasing = 0;
361 
362 	*fingers = 0;
363 
364 	for (i = 0; i < nb_sensors; i++) {
365 		if (xy_sensors[i] < threshold) {
366 			if (is_increasing)
367 				is_increasing = 0;
368 
369 		/*
370 		 * Makes the finger detection more versatile.  For example,
371 		 * two fingers with no gap will be detected.  Also, my
372 		 * tests show it less likely to have intermittent loss
373 		 * of multiple finger readings while moving around (scrolling).
374 		 *
375 		 * Changes the multiple finger detection to counting humps on
376 		 * sensors (transitions from nonincreasing to increasing)
377 		 * instead of counting transitions from low sensors (no
378 		 * finger reading) to high sensors (finger above
379 		 * sensor)
380 		 *
381 		 * - Jason Parekh <jasonparekh@gmail.com>
382 		 */
383 
384 		} else if (i < 1 ||
385 		    (!is_increasing && xy_sensors[i - 1] < xy_sensors[i])) {
386 			(*fingers)++;
387 			is_increasing = 1;
388 		} else if (i > 0 && (xy_sensors[i - 1] - xy_sensors[i] > threshold)) {
389 			is_increasing = 0;
390 		}
391 	}
392 
393 	if (*fingers < 1)     /* No need to continue if no fingers are found. */
394 		return 0;
395 
396 	/*
397 	 * Use a smoothed version of sensor data for movement calculations, to
398 	 * combat noise without needing to rely so heavily on a threshold.
399 	 * This improves tracking.
400 	 *
401 	 * The smoothed array is bigger than the original so that the smoothing
402 	 * doesn't result in edge values being truncated.
403 	 */
404 
405 	memset(dev->smooth, 0, 4 * sizeof(dev->smooth[0]));
406 	/* Pull base values, scaled up to help avoid truncation errors. */
407 	for (i = 0; i < nb_sensors; i++)
408 		dev->smooth[i + 4] = xy_sensors[i] << ATP_SCALE;
409 	memset(&dev->smooth[nb_sensors + 4], 0, 4 * sizeof(dev->smooth[0]));
410 
411 	for (pass = 0; pass < 4; pass++) {
412 		/* Handle edge. */
413 		dev->smooth_tmp[0] = (dev->smooth[0] + dev->smooth[1]) / 2;
414 
415 		/* Average values with neighbors. */
416 		for (i = 1; i < nb_sensors + 7; i++)
417 			dev->smooth_tmp[i] = (dev->smooth[i - 1] +
418 					      dev->smooth[i] * 2 +
419 					      dev->smooth[i + 1]) / 4;
420 
421 		/* Handle other edge. */
422 		dev->smooth_tmp[i] = (dev->smooth[i - 1] + dev->smooth[i]) / 2;
423 
424 		memcpy(dev->smooth, dev->smooth_tmp, sizeof(dev->smooth));
425 	}
426 
427 	for (i = 0; i < nb_sensors + 8; i++) {
428 		/*
429 		 * Skip values if they're small enough to be truncated to 0
430 		 * by scale. Mostly noise.
431 		 */
432 		if ((dev->smooth[i] >> ATP_SCALE) > 0) {
433 			pcum += dev->smooth[i] * i;
434 			psum += dev->smooth[i];
435 		}
436 	}
437 
438 	if (psum > 0) {
439 		*z = psum >> ATP_SCALE;        /* Scale down pressure output. */
440 		return pcum * fact / psum;
441 	}
442 
443 	return 0;
444 }
445 
446 static inline void atp_report_fingers(struct input_dev *input, int fingers)
447 {
448 	input_report_key(input, BTN_TOOL_FINGER, fingers == 1);
449 	input_report_key(input, BTN_TOOL_DOUBLETAP, fingers == 2);
450 	input_report_key(input, BTN_TOOL_TRIPLETAP, fingers > 2);
451 }
452 
453 /* Check URB status and for correct length of data package */
454 
455 #define ATP_URB_STATUS_SUCCESS		0
456 #define ATP_URB_STATUS_ERROR		1
457 #define ATP_URB_STATUS_ERROR_FATAL	2
458 
459 static int atp_status_check(struct urb *urb)
460 {
461 	struct atp *dev = urb->context;
462 	struct usb_interface *intf = dev->intf;
463 
464 	switch (urb->status) {
465 	case 0:
466 		/* success */
467 		break;
468 	case -EOVERFLOW:
469 		if (!dev->overflow_warned) {
470 			dev_warn(&intf->dev,
471 				"appletouch: OVERFLOW with data length %d, actual length is %d\n",
472 				dev->info->datalen, dev->urb->actual_length);
473 			dev->overflow_warned = true;
474 		}
475 		/* fall through */
476 	case -ECONNRESET:
477 	case -ENOENT:
478 	case -ESHUTDOWN:
479 		/* This urb is terminated, clean up */
480 		dev_dbg(&intf->dev,
481 			"atp_complete: urb shutting down with status: %d\n",
482 			urb->status);
483 		return ATP_URB_STATUS_ERROR_FATAL;
484 
485 	default:
486 		dev_dbg(&intf->dev,
487 			"atp_complete: nonzero urb status received: %d\n",
488 			urb->status);
489 		return ATP_URB_STATUS_ERROR;
490 	}
491 
492 	/* drop incomplete datasets */
493 	if (dev->urb->actual_length != dev->info->datalen) {
494 		dprintk("appletouch: incomplete data package"
495 			" (first byte: %d, length: %d).\n",
496 			dev->data[0], dev->urb->actual_length);
497 		return ATP_URB_STATUS_ERROR;
498 	}
499 
500 	return ATP_URB_STATUS_SUCCESS;
501 }
502 
503 static void atp_detect_size(struct atp *dev)
504 {
505 	int i;
506 
507 	/* 17" Powerbooks have extra X sensors */
508 	for (i = dev->info->xsensors; i < ATP_XSENSORS; i++) {
509 		if (dev->xy_cur[i]) {
510 
511 			dev_info(&dev->intf->dev,
512 				"appletouch: 17\" model detected.\n");
513 
514 			input_set_abs_params(dev->input, ABS_X, 0,
515 					     (dev->info->xsensors_17 - 1) *
516 							dev->info->xfact - 1,
517 					     dev->info->fuzz, 0);
518 			break;
519 		}
520 	}
521 }
522 
523 /*
524  * USB interrupt callback functions
525  */
526 
527 /* Interrupt function for older touchpads: FOUNTAIN/GEYSER1/GEYSER2 */
528 
529 static void atp_complete_geyser_1_2(struct urb *urb)
530 {
531 	int x, y, x_z, y_z, x_f, y_f;
532 	int retval, i, j;
533 	int key, fingers;
534 	struct atp *dev = urb->context;
535 	int status = atp_status_check(urb);
536 
537 	if (status == ATP_URB_STATUS_ERROR_FATAL)
538 		return;
539 	else if (status == ATP_URB_STATUS_ERROR)
540 		goto exit;
541 
542 	/* reorder the sensors values */
543 	if (dev->info == &geyser2_info) {
544 		memset(dev->xy_cur, 0, sizeof(dev->xy_cur));
545 
546 		/*
547 		 * The values are laid out like this:
548 		 * Y1, Y2, -, Y3, Y4, -, ..., X1, X2, -, X3, X4, -, ...
549 		 * '-' is an unused value.
550 		 */
551 
552 		/* read X values */
553 		for (i = 0, j = 19; i < 20; i += 2, j += 3) {
554 			dev->xy_cur[i] = dev->data[j];
555 			dev->xy_cur[i + 1] = dev->data[j + 1];
556 		}
557 
558 		/* read Y values */
559 		for (i = 0, j = 1; i < 9; i += 2, j += 3) {
560 			dev->xy_cur[ATP_XSENSORS + i] = dev->data[j];
561 			dev->xy_cur[ATP_XSENSORS + i + 1] = dev->data[j + 1];
562 		}
563 	} else {
564 		for (i = 0; i < 8; i++) {
565 			/* X values */
566 			dev->xy_cur[i +  0] = dev->data[5 * i +  2];
567 			dev->xy_cur[i +  8] = dev->data[5 * i +  4];
568 			dev->xy_cur[i + 16] = dev->data[5 * i + 42];
569 			if (i < 2)
570 				dev->xy_cur[i + 24] = dev->data[5 * i + 44];
571 
572 			/* Y values */
573 			dev->xy_cur[ATP_XSENSORS + i] = dev->data[5 * i +  1];
574 			dev->xy_cur[ATP_XSENSORS + i + 8] = dev->data[5 * i + 3];
575 		}
576 	}
577 
578 	dbg_dump("sample", dev->xy_cur);
579 
580 	if (!dev->valid) {
581 		/* first sample */
582 		dev->valid = true;
583 		dev->x_old = dev->y_old = -1;
584 
585 		/* Store first sample */
586 		memcpy(dev->xy_old, dev->xy_cur, sizeof(dev->xy_old));
587 
588 		/* Perform size detection, if not done already */
589 		if (unlikely(!dev->size_detect_done)) {
590 			atp_detect_size(dev);
591 			dev->size_detect_done = true;
592 			goto exit;
593 		}
594 	}
595 
596 	for (i = 0; i < ATP_XSENSORS + ATP_YSENSORS; i++) {
597 		/* accumulate the change */
598 		signed char change = dev->xy_old[i] - dev->xy_cur[i];
599 		dev->xy_acc[i] -= change;
600 
601 		/* prevent down drifting */
602 		if (dev->xy_acc[i] < 0)
603 			dev->xy_acc[i] = 0;
604 	}
605 
606 	memcpy(dev->xy_old, dev->xy_cur, sizeof(dev->xy_old));
607 
608 	dbg_dump("accumulator", dev->xy_acc);
609 
610 	x = atp_calculate_abs(dev, 0, ATP_XSENSORS,
611 			      dev->info->xfact, &x_z, &x_f);
612 	y = atp_calculate_abs(dev, ATP_XSENSORS, ATP_YSENSORS,
613 			      dev->info->yfact, &y_z, &y_f);
614 	key = dev->data[dev->info->datalen - 1] & ATP_STATUS_BUTTON;
615 
616 	fingers = max(x_f, y_f);
617 
618 	if (x && y && fingers == dev->fingers_old) {
619 		if (dev->x_old != -1) {
620 			x = (dev->x_old * 7 + x) >> 3;
621 			y = (dev->y_old * 7 + y) >> 3;
622 			dev->x_old = x;
623 			dev->y_old = y;
624 
625 			if (debug > 1)
626 				printk(KERN_DEBUG "appletouch: "
627 					"X: %3d Y: %3d Xz: %3d Yz: %3d\n",
628 					x, y, x_z, y_z);
629 
630 			input_report_key(dev->input, BTN_TOUCH, 1);
631 			input_report_abs(dev->input, ABS_X, x);
632 			input_report_abs(dev->input, ABS_Y, y);
633 			input_report_abs(dev->input, ABS_PRESSURE,
634 					 min(ATP_PRESSURE, x_z + y_z));
635 			atp_report_fingers(dev->input, fingers);
636 		}
637 		dev->x_old = x;
638 		dev->y_old = y;
639 
640 	} else if (!x && !y) {
641 
642 		dev->x_old = dev->y_old = -1;
643 		dev->fingers_old = 0;
644 		input_report_key(dev->input, BTN_TOUCH, 0);
645 		input_report_abs(dev->input, ABS_PRESSURE, 0);
646 		atp_report_fingers(dev->input, 0);
647 
648 		/* reset the accumulator on release */
649 		memset(dev->xy_acc, 0, sizeof(dev->xy_acc));
650 	}
651 
652 	if (fingers != dev->fingers_old)
653 		dev->x_old = dev->y_old = -1;
654 	dev->fingers_old = fingers;
655 
656 	input_report_key(dev->input, BTN_LEFT, key);
657 	input_sync(dev->input);
658 
659  exit:
660 	retval = usb_submit_urb(dev->urb, GFP_ATOMIC);
661 	if (retval)
662 		dev_err(&dev->intf->dev,
663 			"atp_complete: usb_submit_urb failed with result %d\n",
664 			retval);
665 }
666 
667 /* Interrupt function for older touchpads: GEYSER3/GEYSER4 */
668 
669 static void atp_complete_geyser_3_4(struct urb *urb)
670 {
671 	int x, y, x_z, y_z, x_f, y_f;
672 	int retval, i, j;
673 	int key, fingers;
674 	struct atp *dev = urb->context;
675 	int status = atp_status_check(urb);
676 
677 	if (status == ATP_URB_STATUS_ERROR_FATAL)
678 		return;
679 	else if (status == ATP_URB_STATUS_ERROR)
680 		goto exit;
681 
682 	/* Reorder the sensors values:
683 	 *
684 	 * The values are laid out like this:
685 	 * -, Y1, Y2, -, Y3, Y4, -, ..., -, X1, X2, -, X3, X4, ...
686 	 * '-' is an unused value.
687 	 */
688 
689 	/* read X values */
690 	for (i = 0, j = 19; i < 20; i += 2, j += 3) {
691 		dev->xy_cur[i] = dev->data[j + 1];
692 		dev->xy_cur[i + 1] = dev->data[j + 2];
693 	}
694 	/* read Y values */
695 	for (i = 0, j = 1; i < 9; i += 2, j += 3) {
696 		dev->xy_cur[ATP_XSENSORS + i] = dev->data[j + 1];
697 		dev->xy_cur[ATP_XSENSORS + i + 1] = dev->data[j + 2];
698 	}
699 
700 	dbg_dump("sample", dev->xy_cur);
701 
702 	/* Just update the base values (i.e. touchpad in untouched state) */
703 	if (dev->data[dev->info->datalen - 1] & ATP_STATUS_BASE_UPDATE) {
704 
705 		dprintk("appletouch: updated base values\n");
706 
707 		memcpy(dev->xy_old, dev->xy_cur, sizeof(dev->xy_old));
708 		goto exit;
709 	}
710 
711 	for (i = 0; i < ATP_XSENSORS + ATP_YSENSORS; i++) {
712 		/* calculate the change */
713 		dev->xy_acc[i] = dev->xy_cur[i] - dev->xy_old[i];
714 
715 		/* this is a round-robin value, so couple with that */
716 		if (dev->xy_acc[i] > 127)
717 			dev->xy_acc[i] -= 256;
718 
719 		if (dev->xy_acc[i] < -127)
720 			dev->xy_acc[i] += 256;
721 
722 		/* prevent down drifting */
723 		if (dev->xy_acc[i] < 0)
724 			dev->xy_acc[i] = 0;
725 	}
726 
727 	dbg_dump("accumulator", dev->xy_acc);
728 
729 	x = atp_calculate_abs(dev, 0, ATP_XSENSORS,
730 			      dev->info->xfact, &x_z, &x_f);
731 	y = atp_calculate_abs(dev, ATP_XSENSORS, ATP_YSENSORS,
732 			      dev->info->yfact, &y_z, &y_f);
733 
734 	key = dev->data[dev->info->datalen - 1] & ATP_STATUS_BUTTON;
735 
736 	fingers = max(x_f, y_f);
737 
738 	if (x && y && fingers == dev->fingers_old) {
739 		if (dev->x_old != -1) {
740 			x = (dev->x_old * 7 + x) >> 3;
741 			y = (dev->y_old * 7 + y) >> 3;
742 			dev->x_old = x;
743 			dev->y_old = y;
744 
745 			if (debug > 1)
746 				printk(KERN_DEBUG "appletouch: X: %3d Y: %3d "
747 				       "Xz: %3d Yz: %3d\n",
748 				       x, y, x_z, y_z);
749 
750 			input_report_key(dev->input, BTN_TOUCH, 1);
751 			input_report_abs(dev->input, ABS_X, x);
752 			input_report_abs(dev->input, ABS_Y, y);
753 			input_report_abs(dev->input, ABS_PRESSURE,
754 					 min(ATP_PRESSURE, x_z + y_z));
755 			atp_report_fingers(dev->input, fingers);
756 		}
757 		dev->x_old = x;
758 		dev->y_old = y;
759 
760 	} else if (!x && !y) {
761 
762 		dev->x_old = dev->y_old = -1;
763 		dev->fingers_old = 0;
764 		input_report_key(dev->input, BTN_TOUCH, 0);
765 		input_report_abs(dev->input, ABS_PRESSURE, 0);
766 		atp_report_fingers(dev->input, 0);
767 
768 		/* reset the accumulator on release */
769 		memset(dev->xy_acc, 0, sizeof(dev->xy_acc));
770 	}
771 
772 	if (fingers != dev->fingers_old)
773 		dev->x_old = dev->y_old = -1;
774 	dev->fingers_old = fingers;
775 
776 	input_report_key(dev->input, BTN_LEFT, key);
777 	input_sync(dev->input);
778 
779 	/*
780 	 * Geysers 3/4 will continue to send packets continually after
781 	 * the first touch unless reinitialised. Do so if it's been
782 	 * idle for a while in order to avoid waking the kernel up
783 	 * several hundred times a second.
784 	 */
785 
786 	/*
787 	 * Button must not be pressed when entering suspend,
788 	 * otherwise we will never release the button.
789 	 */
790 	if (!x && !y && !key) {
791 		dev->idlecount++;
792 		if (dev->idlecount == 10) {
793 			dev->x_old = dev->y_old = -1;
794 			dev->idlecount = 0;
795 			schedule_work(&dev->work);
796 			/* Don't resubmit urb here, wait for reinit */
797 			return;
798 		}
799 	} else
800 		dev->idlecount = 0;
801 
802  exit:
803 	retval = usb_submit_urb(dev->urb, GFP_ATOMIC);
804 	if (retval)
805 		dev_err(&dev->intf->dev,
806 			"atp_complete: usb_submit_urb failed with result %d\n",
807 			retval);
808 }
809 
810 static int atp_open(struct input_dev *input)
811 {
812 	struct atp *dev = input_get_drvdata(input);
813 
814 	if (usb_submit_urb(dev->urb, GFP_KERNEL))
815 		return -EIO;
816 
817 	dev->open = true;
818 	return 0;
819 }
820 
821 static void atp_close(struct input_dev *input)
822 {
823 	struct atp *dev = input_get_drvdata(input);
824 
825 	usb_kill_urb(dev->urb);
826 	cancel_work_sync(&dev->work);
827 	dev->open = false;
828 }
829 
830 static int atp_handle_geyser(struct atp *dev)
831 {
832 	if (dev->info != &fountain_info) {
833 		/* switch to raw sensor mode */
834 		if (atp_geyser_init(dev))
835 			return -EIO;
836 
837 		dev_info(&dev->intf->dev, "Geyser mode initialized.\n");
838 	}
839 
840 	return 0;
841 }
842 
843 static int atp_probe(struct usb_interface *iface,
844 		     const struct usb_device_id *id)
845 {
846 	struct atp *dev;
847 	struct input_dev *input_dev;
848 	struct usb_device *udev = interface_to_usbdev(iface);
849 	struct usb_host_interface *iface_desc;
850 	struct usb_endpoint_descriptor *endpoint;
851 	int int_in_endpointAddr = 0;
852 	int i, error = -ENOMEM;
853 	const struct atp_info *info = (const struct atp_info *)id->driver_info;
854 
855 	/* set up the endpoint information */
856 	/* use only the first interrupt-in endpoint */
857 	iface_desc = iface->cur_altsetting;
858 	for (i = 0; i < iface_desc->desc.bNumEndpoints; i++) {
859 		endpoint = &iface_desc->endpoint[i].desc;
860 		if (!int_in_endpointAddr && usb_endpoint_is_int_in(endpoint)) {
861 			/* we found an interrupt in endpoint */
862 			int_in_endpointAddr = endpoint->bEndpointAddress;
863 			break;
864 		}
865 	}
866 	if (!int_in_endpointAddr) {
867 		dev_err(&iface->dev, "Could not find int-in endpoint\n");
868 		return -EIO;
869 	}
870 
871 	/* allocate memory for our device state and initialize it */
872 	dev = kzalloc(sizeof(struct atp), GFP_KERNEL);
873 	input_dev = input_allocate_device();
874 	if (!dev || !input_dev) {
875 		dev_err(&iface->dev, "Out of memory\n");
876 		goto err_free_devs;
877 	}
878 
879 	dev->udev = udev;
880 	dev->intf = iface;
881 	dev->input = input_dev;
882 	dev->info = info;
883 	dev->overflow_warned = false;
884 
885 	dev->urb = usb_alloc_urb(0, GFP_KERNEL);
886 	if (!dev->urb)
887 		goto err_free_devs;
888 
889 	dev->data = usb_alloc_coherent(dev->udev, dev->info->datalen, GFP_KERNEL,
890 				       &dev->urb->transfer_dma);
891 	if (!dev->data)
892 		goto err_free_urb;
893 
894 	usb_fill_int_urb(dev->urb, udev,
895 			 usb_rcvintpipe(udev, int_in_endpointAddr),
896 			 dev->data, dev->info->datalen,
897 			 dev->info->callback, dev, 1);
898 
899 	error = atp_handle_geyser(dev);
900 	if (error)
901 		goto err_free_buffer;
902 
903 	usb_make_path(udev, dev->phys, sizeof(dev->phys));
904 	strlcat(dev->phys, "/input0", sizeof(dev->phys));
905 
906 	input_dev->name = "appletouch";
907 	input_dev->phys = dev->phys;
908 	usb_to_input_id(dev->udev, &input_dev->id);
909 	input_dev->dev.parent = &iface->dev;
910 
911 	input_set_drvdata(input_dev, dev);
912 
913 	input_dev->open = atp_open;
914 	input_dev->close = atp_close;
915 
916 	set_bit(EV_ABS, input_dev->evbit);
917 
918 	input_set_abs_params(input_dev, ABS_X, 0,
919 			     (dev->info->xsensors - 1) * dev->info->xfact - 1,
920 			     dev->info->fuzz, 0);
921 	input_set_abs_params(input_dev, ABS_Y, 0,
922 			     (dev->info->ysensors - 1) * dev->info->yfact - 1,
923 			     dev->info->fuzz, 0);
924 	input_set_abs_params(input_dev, ABS_PRESSURE, 0, ATP_PRESSURE, 0, 0);
925 
926 	set_bit(EV_KEY, input_dev->evbit);
927 	set_bit(BTN_TOUCH, input_dev->keybit);
928 	set_bit(BTN_TOOL_FINGER, input_dev->keybit);
929 	set_bit(BTN_TOOL_DOUBLETAP, input_dev->keybit);
930 	set_bit(BTN_TOOL_TRIPLETAP, input_dev->keybit);
931 	set_bit(BTN_LEFT, input_dev->keybit);
932 
933 	error = input_register_device(dev->input);
934 	if (error)
935 		goto err_free_buffer;
936 
937 	/* save our data pointer in this interface device */
938 	usb_set_intfdata(iface, dev);
939 
940 	INIT_WORK(&dev->work, atp_reinit);
941 
942 	return 0;
943 
944  err_free_buffer:
945 	usb_free_coherent(dev->udev, dev->info->datalen,
946 			  dev->data, dev->urb->transfer_dma);
947  err_free_urb:
948 	usb_free_urb(dev->urb);
949  err_free_devs:
950 	usb_set_intfdata(iface, NULL);
951 	kfree(dev);
952 	input_free_device(input_dev);
953 	return error;
954 }
955 
956 static void atp_disconnect(struct usb_interface *iface)
957 {
958 	struct atp *dev = usb_get_intfdata(iface);
959 
960 	usb_set_intfdata(iface, NULL);
961 	if (dev) {
962 		usb_kill_urb(dev->urb);
963 		input_unregister_device(dev->input);
964 		usb_free_coherent(dev->udev, dev->info->datalen,
965 				  dev->data, dev->urb->transfer_dma);
966 		usb_free_urb(dev->urb);
967 		kfree(dev);
968 	}
969 	dev_info(&iface->dev, "input: appletouch disconnected\n");
970 }
971 
972 static int atp_recover(struct atp *dev)
973 {
974 	int error;
975 
976 	error = atp_handle_geyser(dev);
977 	if (error)
978 		return error;
979 
980 	if (dev->open && usb_submit_urb(dev->urb, GFP_KERNEL))
981 		return -EIO;
982 
983 	return 0;
984 }
985 
986 static int atp_suspend(struct usb_interface *iface, pm_message_t message)
987 {
988 	struct atp *dev = usb_get_intfdata(iface);
989 
990 	usb_kill_urb(dev->urb);
991 	return 0;
992 }
993 
994 static int atp_resume(struct usb_interface *iface)
995 {
996 	struct atp *dev = usb_get_intfdata(iface);
997 
998 	if (dev->open && usb_submit_urb(dev->urb, GFP_KERNEL))
999 		return -EIO;
1000 
1001 	return 0;
1002 }
1003 
1004 static int atp_reset_resume(struct usb_interface *iface)
1005 {
1006 	struct atp *dev = usb_get_intfdata(iface);
1007 
1008 	return atp_recover(dev);
1009 }
1010 
1011 static struct usb_driver atp_driver = {
1012 	.name		= "appletouch",
1013 	.probe		= atp_probe,
1014 	.disconnect	= atp_disconnect,
1015 	.suspend	= atp_suspend,
1016 	.resume		= atp_resume,
1017 	.reset_resume	= atp_reset_resume,
1018 	.id_table	= atp_table,
1019 };
1020 
1021 module_usb_driver(atp_driver);
1022