/*
* HID driver for Stantum multitouch panels
*
* Copyright (c) 2009 Stephane Chatty <chatty@enac.fr>
*
*/
/*
* 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>
MODULE_AUTHOR("Stephane Chatty <chatty@enac.fr>");
MODULE_DESCRIPTION("Stantum HID multitouch panels");
MODULE_LICENSE("GPL");
#include "hid-ids.h"
struct stantum_data {
__s32 x, y, z, w, h; /* x, y, pressure, width, height */
__u16 id; /* touch id */
bool valid; /* valid finger data, or just placeholder? */
bool first; /* first finger in the HID packet? */
bool activity; /* at least one active finger so far? */
};
static int stantum_input_mapping(struct hid_device *hdev, struct hid_input *hi,
struct hid_field *field, struct hid_usage *usage,
unsigned long **bit, int *max)
{
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);
/* touchscreen emulation */
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);
/* touchscreen emulation */
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) {
case HID_DG_INRANGE:
case HID_DG_CONFIDENCE:
case HID_DG_INPUTMODE:
case HID_DG_DEVICEINDEX:
case HID_DG_CONTACTCOUNT:
case HID_DG_CONTACTMAX:
return -1;
case HID_DG_TIPSWITCH:
/* touchscreen emulation */
hid_map_usage(hi, usage, bit, max, EV_KEY, BTN_TOUCH);
return 1;
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,
1, 1, 0, 0);
return 1;
case HID_DG_TIPPRESSURE:
hid_map_usage(hi, usage, bit, max,
EV_ABS, ABS_MT_PRESSURE);
return 1;
case HID_DG_CONTACTID:
hid_map_usage(hi, usage, bit, max,
EV_ABS, ABS_MT_TRACKING_ID);
return 1;
}
return 0;
case 0xff000000:
/* no input-oriented meaning */
return -1;
}
return 0;
}
static int stantum_input_mapped(struct hid_device *hdev, struct hid_input *hi,
struct hid_field *field, struct hid_usage *usage,
unsigned long **bit, int *max)
{
if (usage->type == EV_KEY || usage->type == EV_ABS)
clear_bit(usage->code, *bit);
return 0;
}
/*
* this function is called when a whole finger has been parsed,
* so that it can decide what to send to the input layer.
*/
static void stantum_filter_event(struct stantum_data *sd,
struct input_dev *input)
{
bool wide;
if (!sd->valid) {
/*
* touchscreen emulation: if the first finger is not valid and
* there previously was finger activity, this is a release
*/
if (sd->first && sd->activity) {
input_event(input, EV_KEY, BTN_TOUCH, 0);
sd->activity = false;
}
return;
}
input_event(input, EV_ABS, ABS_MT_TRACKING_ID, sd->id);
input_event(input, EV_ABS, ABS_MT_POSITION_X, sd->x);
input_event(input, EV_ABS, ABS_MT_POSITION_Y, sd->y);
wide = (sd->w > sd->h);
input_event(input, EV_ABS, ABS_MT_ORIENTATION, wide);
input_event(input, EV_ABS, ABS_MT_TOUCH_MAJOR, wide ? sd->w : sd->h);
input_event(input, EV_ABS, ABS_MT_TOUCH_MINOR, wide ? sd->h : sd->w);
input_event(input, EV_ABS, ABS_MT_PRESSURE, sd->z);
input_mt_sync(input);
sd->valid = false;
/* touchscreen emulation */
if (sd->first) {
if (!sd->activity) {
input_event(input, EV_KEY, BTN_TOUCH, 1);
sd->activity = true;
}
input_event(input, EV_ABS, ABS_X, sd->x);
input_event(input, EV_ABS, ABS_Y, sd->y);
}
sd->first = false;
}
static int stantum_event(struct hid_device *hid, struct hid_field *field,
struct hid_usage *usage, __s32 value)
{
struct stantum_data *sd = hid_get_drvdata(hid);
if (hid->claimed & HID_CLAIMED_INPUT) {
struct input_dev *input = field->hidinput->input;
switch (usage->hid) {
case HID_DG_INRANGE:
/* this is the last field in a finger */
stantum_filter_event(sd, input);
break;
case HID_DG_WIDTH:
sd->w = value;
break;
case HID_DG_HEIGHT:
sd->h = value;
break;
case HID_GD_X:
sd->x = value;
break;
case HID_GD_Y:
sd->y = value;
break;
case HID_DG_TIPPRESSURE:
sd->z = value;
break;
case HID_DG_CONTACTID:
sd->id = value;
break;
case HID_DG_CONFIDENCE:
sd->valid = !!value;
break;
case 0xff000002:
/* this comes only before the first finger */
sd->first = true;
break;
default:
/* ignore the others */
return 1;
}
}
/* 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 stantum_probe(struct hid_device *hdev,
const struct hid_device_id *id)
{
int ret;
struct stantum_data *sd;
sd = kmalloc(sizeof(struct stantum_data), GFP_KERNEL);
if (!sd) {
dev_err(&hdev->dev, "cannot allocate Stantum data\n");
return -ENOMEM;
}
sd->valid = false;
sd->first = false;
sd->activity = false;
hid_set_drvdata(hdev, sd);
ret = hid_parse(hdev);
if (!ret)
ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
if (ret)
kfree(sd);
return ret;
}
static void stantum_remove(struct hid_device *hdev)
{
hid_hw_stop(hdev);
kfree(hid_get_drvdata(hdev));
hid_set_drvdata(hdev, NULL);
}
static const struct hid_device_id stantum_devices[] = {
{ HID_USB_DEVICE(USB_VENDOR_ID_STANTUM, USB_DEVICE_ID_MTP) },
{ }
};
MODULE_DEVICE_TABLE(hid, stantum_devices);
static const struct hid_usage_id stantum_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 stantum_driver = {
.name = "stantum",
.id_table = stantum_devices,
.probe = stantum_probe,
.remove = stantum_remove,
.input_mapping = stantum_input_mapping,
.input_mapped = stantum_input_mapped,
.usage_table = stantum_grabbed_usages,
.event = stantum_event,
};
static int __init stantum_init(void)
{
return hid_register_driver(&stantum_driver);
}
static void __exit stantum_exit(void)
{
hid_unregister_driver(&stantum_driver);
}
module_init(stantum_init);
module_exit(stantum_exit);
