xref: /linux/drivers/input/mouse/appletouch.c (revision 23b0f90ba871f096474e1c27c3d14f455189d2d9)
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			valid;		/* are the samples valid? */
204 	bool			size_detect_done;
205 	bool			overflow_warned;
206 	int			fingers_old;	/* last reported finger count */
207 	int			x_old;		/* last reported x/y, */
208 	int			y_old;		/* used for smoothing */
209 	signed char		xy_cur[ATP_XSENSORS + ATP_YSENSORS];
210 	signed char		xy_old[ATP_XSENSORS + ATP_YSENSORS];
211 	int			xy_acc[ATP_XSENSORS + ATP_YSENSORS];
212 	int			smooth[ATP_SMOOTHSIZE];
213 	int			smooth_tmp[ATP_SMOOTHSIZE];
214 	int			idlecount;	/* number of empty packets */
215 	struct work_struct	work;
216 };
217 
218 #define dbg_dump(msg, tab) \
219 	if (debug > 1) {						\
220 		int __i;						\
221 		printk(KERN_DEBUG "appletouch: %s", msg);		\
222 		for (__i = 0; __i < ATP_XSENSORS + ATP_YSENSORS; __i++)	\
223 			printk(" %02x", tab[__i]);			\
224 		printk("\n");						\
225 	}
226 
227 #define dprintk(format, a...)						\
228 	do {								\
229 		if (debug)						\
230 			printk(KERN_DEBUG format, ##a);			\
231 	} while (0)
232 
233 MODULE_AUTHOR("Johannes Berg");
234 MODULE_AUTHOR("Stelian Pop");
235 MODULE_AUTHOR("Frank Arnold");
236 MODULE_AUTHOR("Michael Hanselmann");
237 MODULE_AUTHOR("Sven Anders");
238 MODULE_DESCRIPTION("Apple PowerBook and MacBook USB touchpad driver");
239 MODULE_LICENSE("GPL");
240 
241 /*
242  * Make the threshold a module parameter
243  */
244 static int threshold = ATP_THRESHOLD;
245 module_param(threshold, int, 0644);
246 MODULE_PARM_DESC(threshold, "Discard any change in data from a sensor"
247 			    " (the trackpad has many of these sensors)"
248 			    " less than this value.");
249 
250 static int debug;
251 module_param(debug, int, 0644);
252 MODULE_PARM_DESC(debug, "Activate debugging output");
253 
254 /*
255  * By default newer Geyser devices send standard USB HID mouse
256  * packets (Report ID 2). This code changes device mode, so it
257  * sends raw sensor reports (Report ID 5).
258  */
259 static int atp_geyser_init(struct atp *dev)
260 {
261 	struct usb_device *udev = dev->udev;
262 	char *data;
263 	int size;
264 	int i;
265 	int ret;
266 
267 	data = kmalloc(8, GFP_KERNEL);
268 	if (!data) {
269 		dev_err(&dev->intf->dev, "Out of memory\n");
270 		return -ENOMEM;
271 	}
272 
273 	size = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
274 			ATP_GEYSER_MODE_READ_REQUEST_ID,
275 			USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
276 			ATP_GEYSER_MODE_REQUEST_VALUE,
277 			ATP_GEYSER_MODE_REQUEST_INDEX, data, 8, 5000);
278 
279 	if (size != 8) {
280 		dprintk("atp_geyser_init: read error\n");
281 		for (i = 0; i < 8; i++)
282 			dprintk("appletouch[%d]: %d\n", i, data[i]);
283 
284 		dev_err(&dev->intf->dev, "Failed to read mode from device.\n");
285 		ret = -EIO;
286 		goto out_free;
287 	}
288 
289 	/* Apply the mode switch */
290 	data[0] = ATP_GEYSER_MODE_VENDOR_VALUE;
291 
292 	size = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
293 			ATP_GEYSER_MODE_WRITE_REQUEST_ID,
294 			USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
295 			ATP_GEYSER_MODE_REQUEST_VALUE,
296 			ATP_GEYSER_MODE_REQUEST_INDEX, data, 8, 5000);
297 
298 	if (size != 8) {
299 		dprintk("atp_geyser_init: write error\n");
300 		for (i = 0; i < 8; i++)
301 			dprintk("appletouch[%d]: %d\n", i, data[i]);
302 
303 		dev_err(&dev->intf->dev, "Failed to request geyser raw mode\n");
304 		ret = -EIO;
305 		goto out_free;
306 	}
307 	ret = 0;
308 out_free:
309 	kfree(data);
310 	return ret;
311 }
312 
313 /*
314  * Reinitialise the device. This usually stops stream of empty packets
315  * coming from it.
316  */
317 static void atp_reinit(struct work_struct *work)
318 {
319 	struct atp *dev = container_of(work, struct atp, work);
320 	int retval;
321 
322 	dprintk("appletouch: putting appletouch to sleep (reinit)\n");
323 	atp_geyser_init(dev);
324 
325 	retval = usb_submit_urb(dev->urb, GFP_ATOMIC);
326 	if (retval)
327 		dev_err(&dev->intf->dev,
328 			"atp_reinit: usb_submit_urb failed with error %d\n",
329 			retval);
330 }
331 
332 static int atp_calculate_abs(struct atp *dev, int offset, int nb_sensors,
333 			     int fact, int *z, int *fingers)
334 {
335 	int i, pass;
336 
337 	/*
338 	 * Use offset to point xy_sensors at the first value in dev->xy_acc
339 	 * for whichever dimension we're looking at this particular go-round.
340 	 */
341 	int *xy_sensors = dev->xy_acc + offset;
342 
343 	/* values to calculate mean */
344 	int pcum = 0, psum = 0;
345 	int is_increasing = 0;
346 
347 	*fingers = 0;
348 
349 	for (i = 0; i < nb_sensors; i++) {
350 		if (xy_sensors[i] < threshold) {
351 			if (is_increasing)
352 				is_increasing = 0;
353 
354 		/*
355 		 * Makes the finger detection more versatile.  For example,
356 		 * two fingers with no gap will be detected.  Also, my
357 		 * tests show it less likely to have intermittent loss
358 		 * of multiple finger readings while moving around (scrolling).
359 		 *
360 		 * Changes the multiple finger detection to counting humps on
361 		 * sensors (transitions from nonincreasing to increasing)
362 		 * instead of counting transitions from low sensors (no
363 		 * finger reading) to high sensors (finger above
364 		 * sensor)
365 		 *
366 		 * - Jason Parekh <jasonparekh@gmail.com>
367 		 */
368 
369 		} else if (i < 1 ||
370 		    (!is_increasing && xy_sensors[i - 1] < xy_sensors[i])) {
371 			(*fingers)++;
372 			is_increasing = 1;
373 		} else if (i > 0 && (xy_sensors[i - 1] - xy_sensors[i] > threshold)) {
374 			is_increasing = 0;
375 		}
376 	}
377 
378 	if (*fingers < 1)     /* No need to continue if no fingers are found. */
379 		return 0;
380 
381 	/*
382 	 * Use a smoothed version of sensor data for movement calculations, to
383 	 * combat noise without needing to rely so heavily on a threshold.
384 	 * This improves tracking.
385 	 *
386 	 * The smoothed array is bigger than the original so that the smoothing
387 	 * doesn't result in edge values being truncated.
388 	 */
389 
390 	memset(dev->smooth, 0, 4 * sizeof(dev->smooth[0]));
391 	/* Pull base values, scaled up to help avoid truncation errors. */
392 	for (i = 0; i < nb_sensors; i++)
393 		dev->smooth[i + 4] = xy_sensors[i] << ATP_SCALE;
394 	memset(&dev->smooth[nb_sensors + 4], 0, 4 * sizeof(dev->smooth[0]));
395 
396 	for (pass = 0; pass < 4; pass++) {
397 		/* Handle edge. */
398 		dev->smooth_tmp[0] = (dev->smooth[0] + dev->smooth[1]) / 2;
399 
400 		/* Average values with neighbors. */
401 		for (i = 1; i < nb_sensors + 7; i++)
402 			dev->smooth_tmp[i] = (dev->smooth[i - 1] +
403 					      dev->smooth[i] * 2 +
404 					      dev->smooth[i + 1]) / 4;
405 
406 		/* Handle other edge. */
407 		dev->smooth_tmp[i] = (dev->smooth[i - 1] + dev->smooth[i]) / 2;
408 
409 		memcpy(dev->smooth, dev->smooth_tmp, sizeof(dev->smooth));
410 	}
411 
412 	for (i = 0; i < nb_sensors + 8; i++) {
413 		/*
414 		 * Skip values if they're small enough to be truncated to 0
415 		 * by scale. Mostly noise.
416 		 */
417 		if ((dev->smooth[i] >> ATP_SCALE) > 0) {
418 			pcum += dev->smooth[i] * i;
419 			psum += dev->smooth[i];
420 		}
421 	}
422 
423 	if (psum > 0) {
424 		*z = psum >> ATP_SCALE;        /* Scale down pressure output. */
425 		return pcum * fact / psum;
426 	}
427 
428 	return 0;
429 }
430 
431 static inline void atp_report_fingers(struct input_dev *input, int fingers)
432 {
433 	input_report_key(input, BTN_TOOL_FINGER, fingers == 1);
434 	input_report_key(input, BTN_TOOL_DOUBLETAP, fingers == 2);
435 	input_report_key(input, BTN_TOOL_TRIPLETAP, fingers > 2);
436 }
437 
438 /* Check URB status and for correct length of data package */
439 
440 #define ATP_URB_STATUS_SUCCESS		0
441 #define ATP_URB_STATUS_ERROR		1
442 #define ATP_URB_STATUS_ERROR_FATAL	2
443 
444 static int atp_status_check(struct urb *urb)
445 {
446 	struct atp *dev = urb->context;
447 	struct usb_interface *intf = dev->intf;
448 
449 	switch (urb->status) {
450 	case 0:
451 		/* success */
452 		break;
453 	case -EOVERFLOW:
454 		if (!dev->overflow_warned) {
455 			dev_warn(&intf->dev,
456 				"appletouch: OVERFLOW with data length %d, actual length is %d\n",
457 				dev->info->datalen, dev->urb->actual_length);
458 			dev->overflow_warned = true;
459 		}
460 		fallthrough;
461 	case -ECONNRESET:
462 	case -ENOENT:
463 	case -ESHUTDOWN:
464 		/* This urb is terminated, clean up */
465 		dev_dbg(&intf->dev,
466 			"atp_complete: urb shutting down with status: %d\n",
467 			urb->status);
468 		return ATP_URB_STATUS_ERROR_FATAL;
469 
470 	default:
471 		dev_dbg(&intf->dev,
472 			"atp_complete: nonzero urb status received: %d\n",
473 			urb->status);
474 		return ATP_URB_STATUS_ERROR;
475 	}
476 
477 	/* drop incomplete datasets */
478 	if (dev->urb->actual_length != dev->info->datalen) {
479 		dprintk("appletouch: incomplete data package"
480 			" (first byte: %d, length: %d).\n",
481 			dev->data[0], dev->urb->actual_length);
482 		return ATP_URB_STATUS_ERROR;
483 	}
484 
485 	return ATP_URB_STATUS_SUCCESS;
486 }
487 
488 static void atp_detect_size(struct atp *dev)
489 {
490 	int i;
491 
492 	/* 17" Powerbooks have extra X sensors */
493 	for (i = dev->info->xsensors; i < ATP_XSENSORS; i++) {
494 		if (dev->xy_cur[i]) {
495 
496 			dev_info(&dev->intf->dev,
497 				"appletouch: 17\" model detected.\n");
498 
499 			input_set_abs_params(dev->input, ABS_X, 0,
500 					     (dev->info->xsensors_17 - 1) *
501 							dev->info->xfact - 1,
502 					     dev->info->fuzz, 0);
503 			break;
504 		}
505 	}
506 }
507 
508 /*
509  * USB interrupt callback functions
510  */
511 
512 /* Interrupt function for older touchpads: FOUNTAIN/GEYSER1/GEYSER2 */
513 
514 static void atp_complete_geyser_1_2(struct urb *urb)
515 {
516 	int x, y, x_z, y_z, x_f, y_f;
517 	int retval, i, j;
518 	int key, fingers;
519 	struct atp *dev = urb->context;
520 	int status = atp_status_check(urb);
521 
522 	if (status == ATP_URB_STATUS_ERROR_FATAL)
523 		return;
524 	else if (status == ATP_URB_STATUS_ERROR)
525 		goto exit;
526 
527 	/* reorder the sensors values */
528 	if (dev->info == &geyser2_info) {
529 		memset(dev->xy_cur, 0, sizeof(dev->xy_cur));
530 
531 		/*
532 		 * The values are laid out like this:
533 		 * Y1, Y2, -, Y3, Y4, -, ..., X1, X2, -, X3, X4, -, ...
534 		 * '-' is an unused value.
535 		 */
536 
537 		/* read X values */
538 		for (i = 0, j = 19; i < 20; i += 2, j += 3) {
539 			dev->xy_cur[i] = dev->data[j];
540 			dev->xy_cur[i + 1] = dev->data[j + 1];
541 		}
542 
543 		/* read Y values */
544 		for (i = 0, j = 1; i < 9; i += 2, j += 3) {
545 			dev->xy_cur[ATP_XSENSORS + i] = dev->data[j];
546 			dev->xy_cur[ATP_XSENSORS + i + 1] = dev->data[j + 1];
547 		}
548 	} else {
549 		for (i = 0; i < 8; i++) {
550 			/* X values */
551 			dev->xy_cur[i +  0] = dev->data[5 * i +  2];
552 			dev->xy_cur[i +  8] = dev->data[5 * i +  4];
553 			dev->xy_cur[i + 16] = dev->data[5 * i + 42];
554 			if (i < 2)
555 				dev->xy_cur[i + 24] = dev->data[5 * i + 44];
556 
557 			/* Y values */
558 			dev->xy_cur[ATP_XSENSORS + i] = dev->data[5 * i +  1];
559 			dev->xy_cur[ATP_XSENSORS + i + 8] = dev->data[5 * i + 3];
560 		}
561 	}
562 
563 	dbg_dump("sample", dev->xy_cur);
564 
565 	if (!dev->valid) {
566 		/* first sample */
567 		dev->valid = true;
568 		dev->x_old = dev->y_old = -1;
569 
570 		/* Store first sample */
571 		memcpy(dev->xy_old, dev->xy_cur, sizeof(dev->xy_old));
572 
573 		/* Perform size detection, if not done already */
574 		if (unlikely(!dev->size_detect_done)) {
575 			atp_detect_size(dev);
576 			dev->size_detect_done = true;
577 			goto exit;
578 		}
579 	}
580 
581 	for (i = 0; i < ATP_XSENSORS + ATP_YSENSORS; i++) {
582 		/* accumulate the change */
583 		signed char change = dev->xy_old[i] - dev->xy_cur[i];
584 		dev->xy_acc[i] -= change;
585 
586 		/* prevent down drifting */
587 		if (dev->xy_acc[i] < 0)
588 			dev->xy_acc[i] = 0;
589 	}
590 
591 	memcpy(dev->xy_old, dev->xy_cur, sizeof(dev->xy_old));
592 
593 	dbg_dump("accumulator", dev->xy_acc);
594 
595 	x = atp_calculate_abs(dev, 0, ATP_XSENSORS,
596 			      dev->info->xfact, &x_z, &x_f);
597 	y = atp_calculate_abs(dev, ATP_XSENSORS, ATP_YSENSORS,
598 			      dev->info->yfact, &y_z, &y_f);
599 	key = dev->data[dev->info->datalen - 1] & ATP_STATUS_BUTTON;
600 
601 	fingers = max(x_f, y_f);
602 
603 	if (x && y && fingers == dev->fingers_old) {
604 		if (dev->x_old != -1) {
605 			x = (dev->x_old * 7 + x) >> 3;
606 			y = (dev->y_old * 7 + y) >> 3;
607 			dev->x_old = x;
608 			dev->y_old = y;
609 
610 			if (debug > 1)
611 				printk(KERN_DEBUG "appletouch: "
612 					"X: %3d Y: %3d Xz: %3d Yz: %3d\n",
613 					x, y, x_z, y_z);
614 
615 			input_report_key(dev->input, BTN_TOUCH, 1);
616 			input_report_abs(dev->input, ABS_X, x);
617 			input_report_abs(dev->input, ABS_Y, y);
618 			input_report_abs(dev->input, ABS_PRESSURE,
619 					 min(ATP_PRESSURE, x_z + y_z));
620 			atp_report_fingers(dev->input, fingers);
621 		}
622 		dev->x_old = x;
623 		dev->y_old = y;
624 
625 	} else if (!x && !y) {
626 
627 		dev->x_old = dev->y_old = -1;
628 		dev->fingers_old = 0;
629 		input_report_key(dev->input, BTN_TOUCH, 0);
630 		input_report_abs(dev->input, ABS_PRESSURE, 0);
631 		atp_report_fingers(dev->input, 0);
632 
633 		/* reset the accumulator on release */
634 		memset(dev->xy_acc, 0, sizeof(dev->xy_acc));
635 	}
636 
637 	if (fingers != dev->fingers_old)
638 		dev->x_old = dev->y_old = -1;
639 	dev->fingers_old = fingers;
640 
641 	input_report_key(dev->input, BTN_LEFT, key);
642 	input_sync(dev->input);
643 
644  exit:
645 	retval = usb_submit_urb(dev->urb, GFP_ATOMIC);
646 	if (retval)
647 		dev_err(&dev->intf->dev,
648 			"atp_complete: usb_submit_urb failed with result %d\n",
649 			retval);
650 }
651 
652 /* Interrupt function for older touchpads: GEYSER3/GEYSER4 */
653 
654 static void atp_complete_geyser_3_4(struct urb *urb)
655 {
656 	int x, y, x_z, y_z, x_f, y_f;
657 	int retval, i, j;
658 	int key, fingers;
659 	struct atp *dev = urb->context;
660 	int status = atp_status_check(urb);
661 
662 	if (status == ATP_URB_STATUS_ERROR_FATAL)
663 		return;
664 	else if (status == ATP_URB_STATUS_ERROR)
665 		goto exit;
666 
667 	/* Reorder the sensors values:
668 	 *
669 	 * The values are laid out like this:
670 	 * -, Y1, Y2, -, Y3, Y4, -, ..., -, X1, X2, -, X3, X4, ...
671 	 * '-' is an unused value.
672 	 */
673 
674 	/* read X values */
675 	for (i = 0, j = 19; i < 20; i += 2, j += 3) {
676 		dev->xy_cur[i] = dev->data[j + 1];
677 		dev->xy_cur[i + 1] = dev->data[j + 2];
678 	}
679 	/* read Y values */
680 	for (i = 0, j = 1; i < 9; i += 2, j += 3) {
681 		dev->xy_cur[ATP_XSENSORS + i] = dev->data[j + 1];
682 		dev->xy_cur[ATP_XSENSORS + i + 1] = dev->data[j + 2];
683 	}
684 
685 	dbg_dump("sample", dev->xy_cur);
686 
687 	/* Just update the base values (i.e. touchpad in untouched state) */
688 	if (dev->data[dev->info->datalen - 1] & ATP_STATUS_BASE_UPDATE) {
689 
690 		dprintk("appletouch: updated base values\n");
691 
692 		memcpy(dev->xy_old, dev->xy_cur, sizeof(dev->xy_old));
693 		goto exit;
694 	}
695 
696 	for (i = 0; i < ATP_XSENSORS + ATP_YSENSORS; i++) {
697 		/* calculate the change */
698 		dev->xy_acc[i] = dev->xy_cur[i] - dev->xy_old[i];
699 
700 		/* this is a round-robin value, so couple with that */
701 		if (dev->xy_acc[i] > 127)
702 			dev->xy_acc[i] -= 256;
703 
704 		if (dev->xy_acc[i] < -127)
705 			dev->xy_acc[i] += 256;
706 
707 		/* prevent down drifting */
708 		if (dev->xy_acc[i] < 0)
709 			dev->xy_acc[i] = 0;
710 	}
711 
712 	dbg_dump("accumulator", dev->xy_acc);
713 
714 	x = atp_calculate_abs(dev, 0, ATP_XSENSORS,
715 			      dev->info->xfact, &x_z, &x_f);
716 	y = atp_calculate_abs(dev, ATP_XSENSORS, ATP_YSENSORS,
717 			      dev->info->yfact, &y_z, &y_f);
718 
719 	key = dev->data[dev->info->datalen - 1] & ATP_STATUS_BUTTON;
720 
721 	fingers = max(x_f, y_f);
722 
723 	if (x && y && fingers == dev->fingers_old) {
724 		if (dev->x_old != -1) {
725 			x = (dev->x_old * 7 + x) >> 3;
726 			y = (dev->y_old * 7 + y) >> 3;
727 			dev->x_old = x;
728 			dev->y_old = y;
729 
730 			if (debug > 1)
731 				printk(KERN_DEBUG "appletouch: X: %3d Y: %3d "
732 				       "Xz: %3d Yz: %3d\n",
733 				       x, y, x_z, y_z);
734 
735 			input_report_key(dev->input, BTN_TOUCH, 1);
736 			input_report_abs(dev->input, ABS_X, x);
737 			input_report_abs(dev->input, ABS_Y, y);
738 			input_report_abs(dev->input, ABS_PRESSURE,
739 					 min(ATP_PRESSURE, x_z + y_z));
740 			atp_report_fingers(dev->input, fingers);
741 		}
742 		dev->x_old = x;
743 		dev->y_old = y;
744 
745 	} else if (!x && !y) {
746 
747 		dev->x_old = dev->y_old = -1;
748 		dev->fingers_old = 0;
749 		input_report_key(dev->input, BTN_TOUCH, 0);
750 		input_report_abs(dev->input, ABS_PRESSURE, 0);
751 		atp_report_fingers(dev->input, 0);
752 
753 		/* reset the accumulator on release */
754 		memset(dev->xy_acc, 0, sizeof(dev->xy_acc));
755 	}
756 
757 	if (fingers != dev->fingers_old)
758 		dev->x_old = dev->y_old = -1;
759 	dev->fingers_old = fingers;
760 
761 	input_report_key(dev->input, BTN_LEFT, key);
762 	input_sync(dev->input);
763 
764 	/*
765 	 * Geysers 3/4 will continue to send packets continually after
766 	 * the first touch unless reinitialised. Do so if it's been
767 	 * idle for a while in order to avoid waking the kernel up
768 	 * several hundred times a second.
769 	 */
770 
771 	/*
772 	 * Button must not be pressed when entering suspend,
773 	 * otherwise we will never release the button.
774 	 */
775 	if (!x && !y && !key) {
776 		dev->idlecount++;
777 		if (dev->idlecount == 10) {
778 			dev->x_old = dev->y_old = -1;
779 			dev->idlecount = 0;
780 			schedule_work(&dev->work);
781 			/* Don't resubmit urb here, wait for reinit */
782 			return;
783 		}
784 	} else
785 		dev->idlecount = 0;
786 
787  exit:
788 	retval = usb_submit_urb(dev->urb, GFP_ATOMIC);
789 	if (retval)
790 		dev_err(&dev->intf->dev,
791 			"atp_complete: usb_submit_urb failed with result %d\n",
792 			retval);
793 }
794 
795 static int atp_open(struct input_dev *input)
796 {
797 	struct atp *dev = input_get_drvdata(input);
798 
799 	if (usb_submit_urb(dev->urb, GFP_KERNEL))
800 		return -EIO;
801 
802 	return 0;
803 }
804 
805 static void atp_close(struct input_dev *input)
806 {
807 	struct atp *dev = input_get_drvdata(input);
808 
809 	usb_kill_urb(dev->urb);
810 	cancel_work_sync(&dev->work);
811 }
812 
813 static int atp_handle_geyser(struct atp *dev)
814 {
815 	if (dev->info != &fountain_info) {
816 		/* switch to raw sensor mode */
817 		if (atp_geyser_init(dev))
818 			return -EIO;
819 
820 		dev_info(&dev->intf->dev, "Geyser mode initialized.\n");
821 	}
822 
823 	return 0;
824 }
825 
826 static int atp_probe(struct usb_interface *iface,
827 		     const struct usb_device_id *id)
828 {
829 	struct atp *dev;
830 	struct input_dev *input_dev;
831 	struct usb_device *udev = interface_to_usbdev(iface);
832 	struct usb_host_interface *iface_desc;
833 	struct usb_endpoint_descriptor *endpoint;
834 	int int_in_endpointAddr = 0;
835 	int i, error = -ENOMEM;
836 	const struct atp_info *info = (const struct atp_info *)id->driver_info;
837 
838 	/* set up the endpoint information */
839 	/* use only the first interrupt-in endpoint */
840 	iface_desc = iface->cur_altsetting;
841 	for (i = 0; i < iface_desc->desc.bNumEndpoints; i++) {
842 		endpoint = &iface_desc->endpoint[i].desc;
843 		if (!int_in_endpointAddr && usb_endpoint_is_int_in(endpoint)) {
844 			/* we found an interrupt in endpoint */
845 			int_in_endpointAddr = endpoint->bEndpointAddress;
846 			break;
847 		}
848 	}
849 	if (!int_in_endpointAddr) {
850 		dev_err(&iface->dev, "Could not find int-in endpoint\n");
851 		return -EIO;
852 	}
853 
854 	/* allocate memory for our device state and initialize it */
855 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
856 	input_dev = input_allocate_device();
857 	if (!dev || !input_dev) {
858 		dev_err(&iface->dev, "Out of memory\n");
859 		goto err_free_devs;
860 	}
861 
862 	dev->udev = udev;
863 	dev->intf = iface;
864 	dev->input = input_dev;
865 	dev->info = info;
866 	dev->overflow_warned = false;
867 
868 	dev->urb = usb_alloc_urb(0, GFP_KERNEL);
869 	if (!dev->urb)
870 		goto err_free_devs;
871 
872 	dev->data = usb_alloc_coherent(dev->udev, dev->info->datalen, GFP_KERNEL,
873 				       &dev->urb->transfer_dma);
874 	if (!dev->data)
875 		goto err_free_urb;
876 
877 	usb_fill_int_urb(dev->urb, udev,
878 			 usb_rcvintpipe(udev, int_in_endpointAddr),
879 			 dev->data, dev->info->datalen,
880 			 dev->info->callback, dev, 1);
881 
882 	error = atp_handle_geyser(dev);
883 	if (error)
884 		goto err_free_buffer;
885 
886 	usb_make_path(udev, dev->phys, sizeof(dev->phys));
887 	strlcat(dev->phys, "/input0", sizeof(dev->phys));
888 
889 	input_dev->name = "appletouch";
890 	input_dev->phys = dev->phys;
891 	usb_to_input_id(dev->udev, &input_dev->id);
892 	input_dev->dev.parent = &iface->dev;
893 
894 	input_set_drvdata(input_dev, dev);
895 
896 	input_dev->open = atp_open;
897 	input_dev->close = atp_close;
898 
899 	set_bit(EV_ABS, input_dev->evbit);
900 
901 	input_set_abs_params(input_dev, ABS_X, 0,
902 			     (dev->info->xsensors - 1) * dev->info->xfact - 1,
903 			     dev->info->fuzz, 0);
904 	input_set_abs_params(input_dev, ABS_Y, 0,
905 			     (dev->info->ysensors - 1) * dev->info->yfact - 1,
906 			     dev->info->fuzz, 0);
907 	input_set_abs_params(input_dev, ABS_PRESSURE, 0, ATP_PRESSURE, 0, 0);
908 
909 	set_bit(EV_KEY, input_dev->evbit);
910 	set_bit(BTN_TOUCH, input_dev->keybit);
911 	set_bit(BTN_TOOL_FINGER, input_dev->keybit);
912 	set_bit(BTN_TOOL_DOUBLETAP, input_dev->keybit);
913 	set_bit(BTN_TOOL_TRIPLETAP, input_dev->keybit);
914 	set_bit(BTN_LEFT, input_dev->keybit);
915 
916 	INIT_WORK(&dev->work, atp_reinit);
917 
918 	error = input_register_device(dev->input);
919 	if (error)
920 		goto err_free_buffer;
921 
922 	/* save our data pointer in this interface device */
923 	usb_set_intfdata(iface, dev);
924 
925 	return 0;
926 
927  err_free_buffer:
928 	usb_free_coherent(dev->udev, dev->info->datalen,
929 			  dev->data, dev->urb->transfer_dma);
930  err_free_urb:
931 	usb_free_urb(dev->urb);
932  err_free_devs:
933 	usb_set_intfdata(iface, NULL);
934 	kfree(dev);
935 	input_free_device(input_dev);
936 	return error;
937 }
938 
939 static void atp_disconnect(struct usb_interface *iface)
940 {
941 	struct atp *dev = usb_get_intfdata(iface);
942 
943 	usb_set_intfdata(iface, NULL);
944 	if (dev) {
945 		usb_kill_urb(dev->urb);
946 		input_unregister_device(dev->input);
947 		usb_free_coherent(dev->udev, dev->info->datalen,
948 				  dev->data, dev->urb->transfer_dma);
949 		usb_free_urb(dev->urb);
950 		kfree(dev);
951 	}
952 	dev_info(&iface->dev, "input: appletouch disconnected\n");
953 }
954 
955 static int atp_recover(struct atp *dev)
956 {
957 	int error;
958 
959 	error = atp_handle_geyser(dev);
960 	if (error)
961 		return error;
962 
963 	guard(mutex)(&dev->input->mutex);
964 	if (input_device_enabled(dev->input) && usb_submit_urb(dev->urb, GFP_KERNEL))
965 		return -EIO;
966 
967 	return 0;
968 }
969 
970 static int atp_suspend(struct usb_interface *iface, pm_message_t message)
971 {
972 	struct atp *dev = usb_get_intfdata(iface);
973 
974 	usb_kill_urb(dev->urb);
975 	return 0;
976 }
977 
978 static int atp_resume(struct usb_interface *iface)
979 {
980 	struct atp *dev = usb_get_intfdata(iface);
981 
982 	guard(mutex)(&dev->input->mutex);
983 	if (input_device_enabled(dev->input) && usb_submit_urb(dev->urb, GFP_KERNEL))
984 		return -EIO;
985 
986 	return 0;
987 }
988 
989 static int atp_reset_resume(struct usb_interface *iface)
990 {
991 	struct atp *dev = usb_get_intfdata(iface);
992 
993 	return atp_recover(dev);
994 }
995 
996 static struct usb_driver atp_driver = {
997 	.name		= "appletouch",
998 	.probe		= atp_probe,
999 	.disconnect	= atp_disconnect,
1000 	.suspend	= atp_suspend,
1001 	.resume		= atp_resume,
1002 	.reset_resume	= atp_reset_resume,
1003 	.id_table	= atp_table,
1004 };
1005 
1006 module_usb_driver(atp_driver);
1007