/*
* HID driver for N-Trig touchscreens
*
* Copyright (c) 2008 Rafi Rubin
* Copyright (c) 2009 Stephane Chatty
*
*/
/*
* 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.
*/
#include <linux/device.h>
#include <linux/hid.h>
#include <linux/module.h>
#include "hid-ids.h"
#define NTRIG_DUPLICATE_USAGES 0x001
#define nt_map_key_clear(c) hid_map_usage_clear(hi, usage, bit, max, \
EV_KEY, (c))
struct ntrig_data {
/* Incoming raw values for a single contact */
__u16 x, y, w, h;
__u16 id;
__u8 confidence;
bool reading_mt;
__u8 first_contact_confidence;
__u8 mt_footer[4];
__u8 mt_foot_count;
};
/*
* this driver is aimed at two firmware versions in circulation:
* - dual pen/finger single touch
* - finger multitouch, pen not working
*/
static int ntrig_input_mapping(struct hid_device *hdev, struct hid_input *hi,
struct hid_field *field, struct hid_usage *usage,
unsigned long **bit, int *max)
{
/* No special mappings needed for the pen and single touch */
if (field->physical)
return 0;
switch (usage->hid & HID_USAGE_PAGE) {
case HID_UP_GENDESK:
switch (usage->hid) {
case HID_GD_X:
hid_map_usage(hi, usage, bit, max,
EV_ABS, ABS_MT_POSITION_X);
input_set_abs_params(hi->input, ABS_X,
field->logical_minimum,
field->logical_maximum, 0, 0);
return 1;
case HID_GD_Y:
hid_map_usage(hi, usage, bit, max,
EV_ABS, ABS_MT_POSITION_Y);
input_set_abs_params(hi->input, ABS_Y,
field->logical_minimum,
field->logical_maximum, 0, 0);
return 1;
}
return 0;
case HID_UP_DIGITIZER:
switch (usage->hid) {
/* we do not want to map these for now */
case HID_DG_CONTACTID: /* Not trustworthy, squelch for now */
case HID_DG_INPUTMODE:
case HID_DG_DEVICEINDEX:
case HID_DG_CONTACTMAX:
return -1;
/* width/height mapped on TouchMajor/TouchMinor/Orientation */
case HID_DG_WIDTH:
hid_map_usage(hi, usage, bit, max,
EV_ABS, ABS_MT_TOUCH_MAJOR);
return 1;
case HID_DG_HEIGHT:
hid_map_usage(hi, usage, bit, max,
EV_ABS, ABS_MT_TOUCH_MINOR);
input_set_abs_params(hi->input, ABS_MT_ORIENTATION,
0, 1, 0, 0);
return 1;
}
return 0;
case 0xff000000:
/* we do not want to map these: no input-oriented meaning */
return -1;
}
return 0;
}
static int ntrig_input_mapped(struct hid_device *hdev, struct hid_input *hi,
struct hid_field *field, struct hid_usage *usage,
unsigned long **bit, int *max)
{
/* No special mappings needed for the pen and single touch */
if (field->physical)
return 0;
if (usage->type == EV_KEY || usage->type == EV_REL
|| usage->type == EV_ABS)
clear_bit(usage->code, *bit);
return 0;
}
/*
* this function is called upon all reports
* so that we can filter contact point information,
* decide whether we are in multi or single touch mode
* and call input_mt_sync after each point if necessary
*/
static int ntrig_event (struct hid_device *hid, struct hid_field *field,
struct hid_usage *usage, __s32 value)
{
struct input_dev *input = field->hidinput->input;
struct ntrig_data *nd = hid_get_drvdata(hid);
/* No special handling needed for the pen */
if (field->application == HID_DG_PEN)
return 0;
if (hid->claimed & HID_CLAIMED_INPUT) {
switch (usage->hid) {
case 0xff000001:
/* Tag indicating the start of a multitouch group */
nd->reading_mt = 1;
nd->first_contact_confidence = 0;
break;
case HID_DG_TIPSWITCH:
/* Prevent emission of touch until validated */
return 1;
case HID_DG_CONFIDENCE:
nd->confidence = value;
break;
case HID_GD_X:
nd->x = value;
/* Clear the contact footer */
nd->mt_foot_count = 0;
break;
case HID_GD_Y:
nd->y = value;
break;
case HID_DG_CONTACTID:
nd->id = value;
break;
case HID_DG_WIDTH:
nd->w = value;
break;
case HID_DG_HEIGHT:
nd->h = value;
/*
* when in single touch mode, this is the last
* report received in a finger event. We want
* to emit a normal (X, Y) position
*/
if (!nd->reading_mt) {
input_report_key(input, BTN_TOOL_DOUBLETAP,
(nd->confidence != 0));
input_event(input, EV_ABS, ABS_X, nd->x);
input_event(input, EV_ABS, ABS_Y, nd->y);
}
break;
case 0xff000002:
/*
* we receive this when the device is in multitouch
* mode. The first of the three values tagged with
* this usage tells if the contact point is real
* or a placeholder
*/
/* Shouldn't get more than 4 footer packets, so skip */
if (nd->mt_foot_count >= 4)
break;
nd->mt_footer[nd->mt_foot_count++] = value;
/* if the footer isn't complete break */
if (nd->mt_foot_count != 4)
break;
/* Pen activity signal, trigger end of touch. */
if (nd->mt_footer[2]) {
nd->confidence = 0;
break;
}
/* If the contact was invalid */
if (!(nd->confidence && nd->mt_footer[0])
|| nd->w <= 250
|| nd->h <= 190) {
nd->confidence = 0;
break;
}
/* emit a normal (X, Y) for the first point only */
if (nd->id == 0) {
nd->first_contact_confidence = nd->confidence;
input_event(input, EV_ABS, ABS_X, nd->x);
input_event(input, EV_ABS, ABS_Y, nd->y);
}
input_event(input, EV_ABS, ABS_MT_POSITION_X, nd->x);
input_event(input, EV_ABS, ABS_MT_POSITION_Y, nd->y);
if (nd->w > nd->h) {
input_event(input, EV_ABS,
ABS_MT_ORIENTATION, 1);
input_event(input, EV_ABS,
ABS_MT_TOUCH_MAJOR, nd->w);
input_event(input, EV_ABS,
ABS_MT_TOUCH_MINOR, nd->h);
} else {
input_event(input, EV_ABS,
ABS_MT_ORIENTATION, 0);
input_event(input, EV_ABS,
ABS_MT_TOUCH_MAJOR, nd->h);
input_event(input, EV_ABS,
ABS_MT_TOUCH_MINOR, nd->w);
}
input_mt_sync(field->hidinput->input);
break;
case HID_DG_CONTACTCOUNT: /* End of a multitouch group */
if (!nd->reading_mt)
break;
nd->reading_mt = 0;
if (nd->first_contact_confidence) {
switch (value) {
case 0: /* for single touch devices */
case 1:
input_report_key(input,
BTN_TOOL_DOUBLETAP, 1);
break;
case 2:
input_report_key(input,
BTN_TOOL_TRIPLETAP, 1);
break;
case 3:
default:
input_report_key(input,
BTN_TOOL_QUADTAP, 1);
}
input_report_key(input, BTN_TOUCH, 1);
} else {
input_report_key(input,
BTN_TOOL_DOUBLETAP, 0);
input_report_key(input,
BTN_TOOL_TRIPLETAP, 0);
input_report_key(input,
BTN_TOOL_QUADTAP, 0);
input_report_key(input, BTN_TOUCH, 0);
}
break;
default:
/* fallback to the generic hidinput handling */
return 0;
}
}
/* we have handled the hidinput part, now remains hiddev */
if ((hid->claimed & HID_CLAIMED_HIDDEV) && hid->hiddev_hid_event)
hid->hiddev_hid_event(hid, field, usage, value);
return 1;
}
static int ntrig_probe(struct hid_device *hdev, const struct hid_device_id *id)
{
int ret;
struct ntrig_data *nd;
struct hid_input *hidinput;
struct input_dev *input;
if (id->driver_data)
hdev->quirks |= HID_QUIRK_MULTI_INPUT;
nd = kmalloc(sizeof(struct ntrig_data), GFP_KERNEL);
if (!nd) {
dev_err(&hdev->dev, "cannot allocate N-Trig data\n");
return -ENOMEM;
}
nd->reading_mt = 0;
hid_set_drvdata(hdev, nd);
ret = hid_parse(hdev);
if (ret) {
dev_err(&hdev->dev, "parse failed\n");
goto err_free;
}
ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_FF);
if (ret) {
dev_err(&hdev->dev, "hw start failed\n");
goto err_free;
}
list_for_each_entry(hidinput, &hdev->inputs, list) {
if (hidinput->report->maxfield < 1)
continue;
input = hidinput->input;
switch (hidinput->report->field[0]->application) {
case HID_DG_PEN:
input->name = "N-Trig Pen";
break;
case HID_DG_TOUCHSCREEN:
/* These keys are redundant for fingers, clear them
* to prevent incorrect identification */
__clear_bit(BTN_TOOL_PEN, input->keybit);
__clear_bit(BTN_TOOL_FINGER, input->keybit);
__clear_bit(BTN_0, input->keybit);
/*
* A little something special to enable
* two and three finger taps.
*/
__set_bit(BTN_TOOL_DOUBLETAP, input->keybit);
__set_bit(BTN_TOOL_TRIPLETAP, input->keybit);
__set_bit(BTN_TOOL_QUADTAP, input->keybit);
/*
* The physical touchscreen (single touch)
* input has a value for physical, whereas
* the multitouch only has logical input
* fields.
*/
input->name =
(hidinput->report->field[0]
->physical) ?
"N-Trig Touchscreen" :
"N-Trig MultiTouch";
break;
}
}
return 0;
err_free:
kfree(nd);
return ret;
}
static void ntrig_remove(struct hid_device *hdev)
{
hid_hw_stop(hdev);
kfree(hid_get_drvdata(hdev));
}
static const struct hid_device_id ntrig_devices[] = {
{ HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN),
.driver_data = NTRIG_DUPLICATE_USAGES },
{ }
};
MODULE_DEVICE_TABLE(hid, ntrig_devices);
static const struct hid_usage_id ntrig_grabbed_usages[] = {
{ HID_ANY_ID, HID_ANY_ID, HID_ANY_ID },
{ HID_ANY_ID - 1, HID_ANY_ID - 1, HID_ANY_ID - 1 }
};
static struct hid_driver ntrig_driver = {
.name = "ntrig",
.id_table = ntrig_devices,
.probe = ntrig_probe,
.remove = ntrig_remove,
.input_mapping = ntrig_input_mapping,
.input_mapped = ntrig_input_mapped,
.usage_table = ntrig_grabbed_usages,
.event = ntrig_event,
};
static int __init ntrig_init(void)
{
return hid_register_driver(&ntrig_driver);
}
static void __exit ntrig_exit(void)
{
hid_unregister_driver(&ntrig_driver);
}
module_init(ntrig_init);
module_exit(ntrig_exit);
MODULE_LICENSE("GPL");
