cregit-Linux how code gets into the kernel

Release 4.11 drivers/input/mouse/appletouch.c

/*
 * Apple USB Touchpad (for post-February 2005 PowerBooks and MacBooks) driver
 *
 * Copyright (C) 2001-2004 Greg Kroah-Hartman (greg@kroah.com)
 * Copyright (C) 2005-2008 Johannes Berg (johannes@sipsolutions.net)
 * Copyright (C) 2005-2008 Stelian Pop (stelian@popies.net)
 * Copyright (C) 2005      Frank Arnold (frank@scirocco-5v-turbo.de)
 * Copyright (C) 2005      Peter Osterlund (petero2@telia.com)
 * Copyright (C) 2005      Michael Hanselmann (linux-kernel@hansmi.ch)
 * Copyright (C) 2006      Nicolas Boichat (nicolas@boichat.ch)
 * Copyright (C) 2007-2008 Sven Anders (anders@anduras.de)
 *
 * Thanks to Alex Harper <basilisk@foobox.net> for his inputs.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 */

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/usb/input.h>

/*
 * Note: We try to keep the touchpad aspect ratio while still doing only
 * simple arithmetics:
 *      0 <= x <= (xsensors - 1) * xfact
 *      0 <= y <= (ysensors - 1) * yfact
 */

struct atp_info {
	
int xsensors;				/* number of X sensors */
	
int xsensors_17;			/* 17" models have more sensors */
	
int ysensors;				/* number of Y sensors */
	
int xfact;				/* X multiplication factor */
	
int yfact;				/* Y multiplication factor */
	
int datalen;				/* size of USB transfers */
	
void (*callback)(struct urb *);		/* callback function */
	
int fuzz;				/* fuzz touchpad generates */
};

static void atp_complete_geyser_1_2(struct urb *urb);
static void atp_complete_geyser_3_4(struct urb *urb);


static const struct atp_info fountain_info = {
	.xsensors	= 16,
	.xsensors_17	= 26,
	.ysensors	= 16,
	.xfact		= 64,
	.yfact		= 43,
	.datalen	= 81,
	.callback	= atp_complete_geyser_1_2,
	.fuzz		= 16,
};


static const struct atp_info geyser1_info = {
	.xsensors	= 16,
	.xsensors_17	= 26,
	.ysensors	= 16,
	.xfact		= 64,
	.yfact		= 43,
	.datalen	= 81,
	.callback	= atp_complete_geyser_1_2,
	.fuzz		= 16,
};


static const struct atp_info geyser2_info = {
	.xsensors	= 15,
	.xsensors_17	= 20,
	.ysensors	= 9,
	.xfact		= 64,
	.yfact		= 43,
	.datalen	= 64,
	.callback	= atp_complete_geyser_1_2,
	.fuzz		= 0,
};


static const struct atp_info geyser3_info = {
	.xsensors	= 20,
	.ysensors	= 10,
	.xfact		= 64,
	.yfact		= 64,
	.datalen	= 64,
	.callback	= atp_complete_geyser_3_4,
	.fuzz		= 0,
};


static const struct atp_info geyser4_info = {
	.xsensors	= 20,
	.ysensors	= 10,
	.xfact		= 64,
	.yfact		= 64,
	.datalen	= 64,
	.callback	= atp_complete_geyser_3_4,
	.fuzz		= 0,
};


#define ATP_DEVICE(prod, info)					\
{                                                               \
        .match_flags = USB_DEVICE_ID_MATCH_DEVICE |             \
                       USB_DEVICE_ID_MATCH_INT_CLASS |          \
                       USB_DEVICE_ID_MATCH_INT_PROTOCOL,        \
        .idVendor = 0x05ac, /* Apple */				\
        .idProduct = (prod),                                    \
        .bInterfaceClass = 0x03,                                \
        .bInterfaceProtocol = 0x02,                             \
        .driver_info = (unsigned long) &info,                   \
}

/*
 * Table of devices (Product IDs) that work with this driver.
 * (The names come from Info.plist in AppleUSBTrackpad.kext,
 *  According to Info.plist Geyser IV is the same as Geyser III.)
 */


static struct usb_device_id atp_table[] = {
	/* PowerBooks Feb 2005, iBooks G4 */
	ATP_DEVICE(0x020e, fountain_info),	/* FOUNTAIN ANSI */
	ATP_DEVICE(0x020f, fountain_info),	/* FOUNTAIN ISO */
	ATP_DEVICE(0x030a, fountain_info),	/* FOUNTAIN TP ONLY */
	ATP_DEVICE(0x030b, geyser1_info),	/* GEYSER 1 TP ONLY */

	/* PowerBooks Oct 2005 */
	ATP_DEVICE(0x0214, geyser2_info),	/* GEYSER 2 ANSI */
	ATP_DEVICE(0x0215, geyser2_info),	/* GEYSER 2 ISO */
	ATP_DEVICE(0x0216, geyser2_info),	/* GEYSER 2 JIS */

	/* Core Duo MacBook & MacBook Pro */
	ATP_DEVICE(0x0217, geyser3_info),	/* GEYSER 3 ANSI */
	ATP_DEVICE(0x0218, geyser3_info),	/* GEYSER 3 ISO */
	ATP_DEVICE(0x0219, geyser3_info),	/* GEYSER 3 JIS */

	/* Core2 Duo MacBook & MacBook Pro */
	ATP_DEVICE(0x021a, geyser4_info),	/* GEYSER 4 ANSI */
	ATP_DEVICE(0x021b, geyser4_info),	/* GEYSER 4 ISO */
	ATP_DEVICE(0x021c, geyser4_info),	/* GEYSER 4 JIS */

	/* Core2 Duo MacBook3,1 */
	ATP_DEVICE(0x0229, geyser4_info),	/* GEYSER 4 HF ANSI */
	ATP_DEVICE(0x022a, geyser4_info),	/* GEYSER 4 HF ISO */
	ATP_DEVICE(0x022b, geyser4_info),	/* GEYSER 4 HF JIS */

	/* Terminating entry */
	{ }
};
MODULE_DEVICE_TABLE(usb, atp_table);

/* maximum number of sensors */

#define ATP_XSENSORS	26

#define ATP_YSENSORS	16

/*
 * The largest possible bank of sensors with additional buffer of 4 extra values
 * on either side, for an array of smoothed sensor values.
 */

#define ATP_SMOOTHSIZE	34

/* maximum pressure this driver will report */

#define ATP_PRESSURE	300

/*
 * Threshold for the touchpad sensors. Any change less than ATP_THRESHOLD is
 * ignored.
 */

#define ATP_THRESHOLD	5

/*
 * How far we'll bitshift our sensor values before averaging them. Mitigates
 * rounding errors.
 */

#define ATP_SCALE	12

/* Geyser initialization constants */

#define ATP_GEYSER_MODE_READ_REQUEST_ID		1

#define ATP_GEYSER_MODE_WRITE_REQUEST_ID	9

#define ATP_GEYSER_MODE_REQUEST_VALUE		0x300

#define ATP_GEYSER_MODE_REQUEST_INDEX		0

#define ATP_GEYSER_MODE_VENDOR_VALUE		0x04

/**
 * enum atp_status_bits - status bit meanings
 *
 * These constants represent the meaning of the status bits.
 * (only Geyser 3/4)
 *
 * @ATP_STATUS_BUTTON: The button was pressed
 * @ATP_STATUS_BASE_UPDATE: Update of the base values (untouched pad)
 * @ATP_STATUS_FROM_RESET: Reset previously performed
 */

enum atp_status_bits {
	
ATP_STATUS_BUTTON	= BIT(0),
	
ATP_STATUS_BASE_UPDATE	= BIT(2),
	
ATP_STATUS_FROM_RESET	= BIT(4),
};

/* Structure to hold all of our device specific stuff */

struct atp {
	
char			phys[64];
	
struct usb_device	*udev;		/* usb device */
	
struct usb_interface	*intf;		/* usb interface */
	
struct urb		*urb;		/* usb request block */
	
u8			*data;		/* transferred data */
	
struct input_dev	*input;		/* input dev */
	
const struct atp_info	*info;		/* touchpad model */
	
bool			open;
	
bool			valid;		/* are the samples valid? */
	
bool			size_detect_done;
	
bool			overflow_warned;
	
int			fingers_old;	/* last reported finger count */
	
int			x_old;		/* last reported x/y, */
	
int			y_old;		/* used for smoothing */
	
signed char		xy_cur[ATP_XSENSORS + ATP_YSENSORS];
	
signed char		xy_old[ATP_XSENSORS + ATP_YSENSORS];
	
int			xy_acc[ATP_XSENSORS + ATP_YSENSORS];
	
int			smooth[ATP_SMOOTHSIZE];
	
int			smooth_tmp[ATP_SMOOTHSIZE];
	
int			idlecount;	/* number of empty packets */
	
struct work_struct	work;
};


#define dbg_dump(msg, tab) \
	if (debug > 1) {                                                \
                int __i;                                                \
                printk(KERN_DEBUG "appletouch: %s", msg);               \
                for (__i = 0; __i < ATP_XSENSORS + ATP_YSENSORS; __i++) \
                        printk(" %02x", tab[__i]);                      \
                printk("\n");                                           \
        }


#define dprintk(format, a...)						\
	do {                                                            \
                if (debug)                                              \
                        printk(KERN_DEBUG format, ##a);                 \
        } while (0)

MODULE_AUTHOR("Johannes Berg");
MODULE_AUTHOR("Stelian Pop");
MODULE_AUTHOR("Frank Arnold");
MODULE_AUTHOR("Michael Hanselmann");
MODULE_AUTHOR("Sven Anders");
MODULE_DESCRIPTION("Apple PowerBook and MacBook USB touchpad driver");
MODULE_LICENSE("GPL");

/*
 * Make the threshold a module parameter
 */

static int threshold = ATP_THRESHOLD;
module_param(threshold, int, 0644);
MODULE_PARM_DESC(threshold, "Discard any change in data from a sensor"
			    " (the trackpad has many of these sensors)"
			    " less than this value.");


static int debug;
module_param(debug, int, 0644);
MODULE_PARM_DESC(debug, "Activate debugging output");

/*
 * By default newer Geyser devices send standard USB HID mouse
 * packets (Report ID 2). This code changes device mode, so it
 * sends raw sensor reports (Report ID 5).
 */

static int atp_geyser_init(struct atp *dev) { struct usb_device *udev = dev->udev; char *data; int size; int i; int ret; data = kmalloc(8, GFP_KERNEL); if (!data) { dev_err(&dev->intf->dev, "Out of memory\n"); return -ENOMEM; } size = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0), ATP_GEYSER_MODE_READ_REQUEST_ID, USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE, ATP_GEYSER_MODE_REQUEST_VALUE, ATP_GEYSER_MODE_REQUEST_INDEX, data, 8, 5000); if (size != 8) { dprintk("atp_geyser_init: read error\n"); for (i = 0; i < 8; i++) dprintk("appletouch[%d]: %d\n", i, data[i]); dev_err(&dev->intf->dev, "Failed to read mode from device.\n"); ret = -EIO; goto out_free; } /* Apply the mode switch */ data[0] = ATP_GEYSER_MODE_VENDOR_VALUE; size = usb_control_msg(udev, usb_sndctrlpipe(udev, 0), ATP_GEYSER_MODE_WRITE_REQUEST_ID, USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE, ATP_GEYSER_MODE_REQUEST_VALUE, ATP_GEYSER_MODE_REQUEST_INDEX, data, 8, 5000); if (size != 8) { dprintk("atp_geyser_init: write error\n"); for (i = 0; i < 8; i++) dprintk("appletouch[%d]: %d\n", i, data[i]); dev_err(&dev->intf->dev, "Failed to request geyser raw mode\n"); ret = -EIO; goto out_free; } ret = 0; out_free: kfree(data); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Soeren Sonnenburg10740.07%114.29%
Johannes Berg6323.60%114.29%
Bob Copeland5119.10%114.29%
Greg Kroah-Hartman3814.23%342.86%
Dmitry Torokhov83.00%114.29%
Total267100.00%7100.00%

/* * Reinitialise the device. This usually stops stream of empty packets * coming from it. */
static void atp_reinit(struct work_struct *work) { struct atp *dev = container_of(work, struct atp, work); int retval; dprintk("appletouch: putting appletouch to sleep (reinit)\n"); atp_geyser_init(dev); retval = usb_submit_urb(dev->urb, GFP_ATOMIC); if (retval) dev_err(&dev->intf->dev, "atp_reinit: usb_submit_urb failed with error %d\n", retval); }

Contributors

PersonTokensPropCommitsCommitProp
Soeren Sonnenburg2841.18%116.67%
Dmitry Torokhov2536.76%116.67%
Greg Kroah-Hartman1014.71%350.00%
Johannes Berg57.35%116.67%
Total68100.00%6100.00%


static int atp_calculate_abs(struct atp *dev, int offset, int nb_sensors, int fact, int *z, int *fingers) { int i, pass; /* * Use offset to point xy_sensors at the first value in dev->xy_acc * for whichever dimension we're looking at this particular go-round. */ int *xy_sensors = dev->xy_acc + offset; /* values to calculate mean */ int pcum = 0, psum = 0; int is_increasing = 0; *fingers = 0; for (i = 0; i < nb_sensors; i++) { if (xy_sensors[i] < threshold) { if (is_increasing) is_increasing = 0; /* * Makes the finger detection more versatile. For example, * two fingers with no gap will be detected. Also, my * tests show it less likely to have intermittent loss * of multiple finger readings while moving around (scrolling). * * Changes the multiple finger detection to counting humps on * sensors (transitions from nonincreasing to increasing) * instead of counting transitions from low sensors (no * finger reading) to high sensors (finger above * sensor) * * - Jason Parekh <jasonparekh@gmail.com> */ } else if (i < 1 || (!is_increasing && xy_sensors[i - 1] < xy_sensors[i])) { (*fingers)++; is_increasing = 1; } else if (i > 0 && (xy_sensors[i - 1] - xy_sensors[i] > threshold)) { is_increasing = 0; } } if (*fingers < 1) /* No need to continue if no fingers are found. */ return 0; /* * Use a smoothed version of sensor data for movement calculations, to * combat noise without needing to rely so heavily on a threshold. * This improves tracking. * * The smoothed array is bigger than the original so that the smoothing * doesn't result in edge values being truncated. */ memset(dev->smooth, 0, 4 * sizeof(dev->smooth[0])); /* Pull base values, scaled up to help avoid truncation errors. */ for (i = 0; i < nb_sensors; i++) dev->smooth[i + 4] = xy_sensors[i] << ATP_SCALE; memset(&dev->smooth[nb_sensors + 4], 0, 4 * sizeof(dev->smooth[0])); for (pass = 0; pass < 4; pass++) { /* Handle edge. */ dev->smooth_tmp[0] = (dev->smooth[0] + dev->smooth[1]) / 2; /* Average values with neighbors. */ for (i = 1; i < nb_sensors + 7; i++) dev->smooth_tmp[i] = (dev->smooth[i - 1] + dev->smooth[i] * 2 + dev->smooth[i + 1]) / 4; /* Handle other edge. */ dev->smooth_tmp[i] = (dev->smooth[i - 1] + dev->smooth[i]) / 2; memcpy(dev->smooth, dev->smooth_tmp, sizeof(dev->smooth)); } for (i = 0; i < nb_sensors + 8; i++) { /* * Skip values if they're small enough to be truncated to 0 * by scale. Mostly noise. */ if ((dev->smooth[i] >> ATP_SCALE) > 0) { pcum += dev->smooth[i] * i; psum += dev->smooth[i]; } } if (psum > 0) { *z = psum >> ATP_SCALE; /* Scale down pressure output. */ return pcum * fact / psum; } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Clinton Sprain29561.97%125.00%
Stelian Pop12025.21%125.00%
Jason Parekh5611.76%125.00%
Jeremy Huddleston51.05%125.00%
Total476100.00%4100.00%


static inline void atp_report_fingers(struct input_dev *input, int fingers) { input_report_key(input, BTN_TOOL_FINGER, fingers == 1); input_report_key(input, BTN_TOOL_DOUBLETAP, fingers == 2); input_report_key(input, BTN_TOOL_TRIPLETAP, fingers > 2); }

Contributors

PersonTokensPropCommitsCommitProp
Stelian Pop48100.00%1100.00%
Total48100.00%1100.00%

/* Check URB status and for correct length of data package */ #define ATP_URB_STATUS_SUCCESS 0 #define ATP_URB_STATUS_ERROR 1 #define ATP_URB_STATUS_ERROR_FATAL 2
static int atp_status_check(struct urb *urb) { struct atp *dev = urb->context; struct usb_interface *intf = dev->intf; switch (urb->status) { case 0: /* success */ break; case -EOVERFLOW: if (!dev->overflow_warned) { dev_warn(&intf->dev, "appletouch: OVERFLOW with data length %d, actual length is %d\n", dev->info->datalen, dev->urb->actual_length); dev->overflow_warned = true; } case -ECONNRESET: case -ENOENT: case -ESHUTDOWN: /* This urb is terminated, clean up */ dev_dbg(&intf->dev, "atp_complete: urb shutting down with status: %d\n", urb->status); return ATP_URB_STATUS_ERROR_FATAL; default: dev_dbg(&intf->dev, "atp_complete: nonzero urb status received: %d\n", urb->status); return ATP_URB_STATUS_ERROR; } /* drop incomplete datasets */ if (dev->urb->actual_length != dev->info->datalen) { dprintk("appletouch: incomplete data package" " (first byte: %d, length: %d).\n", dev->data[0], dev->urb->actual_length); return ATP_URB_STATUS_ERROR; } return ATP_URB_STATUS_SUCCESS; }

Contributors

PersonTokensPropCommitsCommitProp
Stelian Pop7744.51%225.00%
Michael Hanselmann3218.50%112.50%
Greg Kroah-Hartman3017.34%225.00%
Sven Anders169.25%112.50%
Nicolas Boichat158.67%112.50%
Johannes Berg31.73%112.50%
Total173100.00%8100.00%


static void atp_detect_size(struct atp *dev) { int i; /* 17" Powerbooks have extra X sensors */ for (i = dev->info->xsensors; i < ATP_XSENSORS; i++) { if (dev->xy_cur[i]) { dev_info(&dev->intf->dev, "appletouch: 17\" model detected.\n"); input_set_abs_params(dev->input, ABS_X, 0, (dev->info->xsensors_17 - 1) * dev->info->xfact - 1, dev->info->fuzz, 0); break; } } }

Contributors

PersonTokensPropCommitsCommitProp
Stelian Pop8286.32%125.00%
Greg Kroah-Hartman88.42%250.00%
Clinton Sprain55.26%125.00%
Total95100.00%4100.00%

/* * USB interrupt callback functions */ /* Interrupt function for older touchpads: FOUNTAIN/GEYSER1/GEYSER2 */
static void atp_complete_geyser_1_2(struct urb *urb) { int x, y, x_z, y_z, x_f, y_f; int retval, i, j; int key, fingers; struct atp *dev = urb->context; int status = atp_status_check(urb); if (status == ATP_URB_STATUS_ERROR_FATAL) return; else if (status == ATP_URB_STATUS_ERROR) goto exit; /* reorder the sensors values */ if (dev->info == &geyser2_info) { memset(dev->xy_cur, 0, sizeof(dev->xy_cur)); /* * The values are laid out like this: * Y1, Y2, -, Y3, Y4, -, ..., X1, X2, -, X3, X4, -, ... * '-' is an unused value. */ /* read X values */ for (i = 0, j = 19; i < 20; i += 2, j += 3) { dev->xy_cur[i] = dev->data[j]; dev->xy_cur[i + 1] = dev->data[j + 1]; } /* read Y values */ for (i = 0, j = 1; i < 9; i += 2, j += 3) { dev->xy_cur[ATP_XSENSORS + i] = dev->data[j]; dev->xy_cur[ATP_XSENSORS + i + 1] = dev->data[j + 1]; } } else { for (i = 0; i < 8; i++) { /* X values */ dev->xy_cur[i + 0] = dev->data[5 * i + 2]; dev->xy_cur[i + 8] = dev->data[5 * i + 4]; dev->xy_cur[i + 16] = dev->data[5 * i + 42]; if (i < 2) dev->xy_cur[i + 24] = dev->data[5 * i + 44]; /* Y values */ dev->xy_cur[ATP_XSENSORS + i] = dev->data[5 * i + 1]; dev->xy_cur[ATP_XSENSORS + i + 8] = dev->data[5 * i + 3]; } } dbg_dump("sample", dev->xy_cur); if (!dev->valid) { /* first sample */ dev->valid = true; dev->x_old = dev->y_old = -1; /* Store first sample */ memcpy(dev->xy_old, dev->xy_cur, sizeof(dev->xy_old)); /* Perform size detection, if not done already */ if (unlikely(!dev->size_detect_done)) { atp_detect_size(dev); dev->size_detect_done = 1; goto exit; } } for (i = 0; i < ATP_XSENSORS + ATP_YSENSORS; i++) { /* accumulate the change */ signed char change = dev->xy_old[i] - dev->xy_cur[i]; dev->xy_acc[i] -= change; /* prevent down drifting */ if (dev->xy_acc[i] < 0) dev->xy_acc[i] = 0; } memcpy(dev->xy_old, dev->xy_cur, sizeof(dev->xy_old)); dbg_dump("accumulator", dev->xy_acc); x = atp_calculate_abs(dev, 0, ATP_XSENSORS, dev->info->xfact, &x_z, &x_f); y = atp_calculate_abs(dev, ATP_XSENSORS, ATP_YSENSORS, dev->info->yfact, &y_z, &y_f); key = dev->data[dev->info->datalen - 1] & ATP_STATUS_BUTTON; fingers = max(x_f, y_f); if (x && y && fingers == dev->fingers_old) { if (dev->x_old != -1) { x = (dev->x_old * 7 + x) >> 3; y = (dev->y_old * 7 + y) >> 3; dev->x_old = x; dev->y_old = y; if (debug > 1) printk(KERN_DEBUG "appletouch: " "X: %3d Y: %3d Xz: %3d Yz: %3d\n", x, y, x_z, y_z); input_report_key(dev->input, BTN_TOUCH, 1); input_report_abs(dev->input, ABS_X, x); input_report_abs(dev->input, ABS_Y, y); input_report_abs(dev->input, ABS_PRESSURE, min(ATP_PRESSURE, x_z + y_z)); atp_report_fingers(dev->input, fingers); } dev->x_old = x; dev->y_old = y; } else if (!x && !y) { dev->x_old = dev->y_old = -1; dev->fingers_old = 0; input_report_key(dev->input, BTN_TOUCH, 0); input_report_abs(dev->input, ABS_PRESSURE, 0); atp_report_fingers(dev->input, 0); /* reset the accumulator on release */ memset(dev->xy_acc, 0, sizeof(dev->xy_acc)); } if (fingers != dev->fingers_old) dev->x_old = dev->y_old = -1; dev->fingers_old = fingers; input_report_key(dev->input, BTN_LEFT, key); input_sync(dev->input); exit: retval = usb_submit_urb(dev->urb, GFP_ATOMIC); if (retval) dev_err(&dev->intf->dev, "atp_complete: usb_submit_urb failed with result %d\n", retval); }

Contributors

PersonTokensPropCommitsCommitProp
Sven Anders59664.78%325.00%
Nicolas Boichat13614.78%18.33%
Michael Hanselmann768.26%18.33%
Clinton Sprain566.09%216.67%
Stelian Pop454.89%216.67%
Greg Kroah-Hartman90.98%216.67%
Benjamin Herrenschmidt20.22%18.33%
Total920100.00%12100.00%

/* Interrupt function for older touchpads: GEYSER3/GEYSER4 */
static void atp_complete_geyser_3_4(struct urb *urb) { int x, y, x_z, y_z, x_f, y_f; int retval, i, j; int key, fingers; struct atp *dev = urb->context; int status = atp_status_check(urb); if (status == ATP_URB_STATUS_ERROR_FATAL) return; else if (status == ATP_URB_STATUS_ERROR) goto exit; /* Reorder the sensors values: * * The values are laid out like this: * -, Y1, Y2, -, Y3, Y4, -, ..., -, X1, X2, -, X3, X4, ... * '-' is an unused value. */ /* read X values */ for (i = 0, j = 19; i < 20; i += 2, j += 3) { dev->xy_cur[i] = dev->data[j + 1]; dev->xy_cur[i + 1] = dev->data[j + 2]; } /* read Y values */ for (i = 0, j = 1; i < 9; i += 2, j += 3) { dev->xy_cur[ATP_XSENSORS + i] =