/*
* HID driver for eGalax dual-touch panels
*
* Copyright (c) 2010 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>
#include <linux/usb.h>
#include <linux/slab.h>
#include "usbhid/usbhid.h"
MODULE_AUTHOR("Stephane Chatty <chatty@enac.fr>");
MODULE_DESCRIPTION("eGalax dual-touch panel");
MODULE_LICENSE("GPL");
#include "hid-ids.h"
struct egalax_data {
__u16 x, y, z;
__u8 id;
bool first; /* is this the first finger in the frame? */
bool valid; /* valid finger data, or just placeholder? */
bool activity; /* at least one active finger previously? */
__u16 lastx, lasty; /* latest valid (x, y) in the frame */
};
static int egalax_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_TIPSWITCH:
/* touchscreen emulation */
hid_map_usage(hi, usage, bit, max, EV_KEY, BTN_TOUCH);
return 1;
case HID_DG_INRANGE:
case HID_DG_CONFIDENCE:
case HID_DG_CONTACTCOUNT:
case HID_DG_CONTACTMAX:
return -1;
case HID_DG_CONTACTID:
hid_map_usage(hi, usage, bit, max,
EV_ABS, ABS_MT_TRACKING_ID);
return 1;
case HID_DG_TIPPRESSURE:
hid_map_usage(hi, usage, bit, max,
EV_ABS, ABS_MT_PRESSURE);
return 1;
}
return 0;
}
/* ignore others (from other reports we won't get anyway) */
return -1;
}
static int egalax_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 egalax_filter_event(struct egalax_data *td, struct input_dev *input)
{
td->first = !td->first; /* touchscreen emulation */
if (td->valid) {
/* emit multitouch events */
input_event(input, EV_ABS, ABS_MT_TRACKING_ID, td->id);
input_event(input, EV_ABS, ABS_MT_POSITION_X, td->x);
input_event(input, EV_ABS, ABS_MT_POSITION_Y, td->y);
input_event(input, EV_ABS, ABS_MT_PRESSURE, td->z);
input_mt_sync(input);
/*
* touchscreen emulation: store (x, y) as
* the last valid values in this frame
*/
td->lastx = td->x;
td->lasty = td->y;
}
/*
* touchscreen emulation: if this is the second finger and at least
* one in this frame is valid, the latest valid in the frame is
* the oldest on the panel, the one we want for single touch
*/
if (!td->first && td->activity) {
input_event(input, EV_ABS, ABS_X, td->lastx);
input_event(input, EV_ABS, ABS_Y, td->lasty);
}
if (!td->valid) {
/*
* touchscreen emulation: if the first finger is invalid
* and there previously was finger activity, this is a release
*/
if (td->first && td->activity) {
input_event(input, EV_KEY, BTN_TOUCH, 0);
td->activity = false;
}
return;
}
/* touchscreen emulation: if no previous activity, emit touch event */
if (!td->activity) {
input_event(input, EV_KEY, BTN_TOUCH, 1);
td->activity = true;
}
}
static int egalax_event(struct hid_device *hid, struct hid_field *field,
struct hid_usage *usage, __s32 value)
{
struct egalax_data *td = hid_get_drvdata(hid);
if (hid->claimed & HID_CLAIMED_INPUT) {
struct input_dev *input = field->hidinput->input;
switch (usage->hid) {
case HID_DG_INRANGE:
case HID_DG_CONFIDENCE:
/* avoid interference from generic hidinput handling */
break;
case HID_DG_TIPSWITCH:
td->valid = value;
break;
case HID_DG_TIPPRESSURE:
td->z = value;
break;
case HID_DG_CONTACTID:
td->id = value;
break;
case HID_GD_X:
td->x = value;
break;
case HID_GD_Y:
td->y = value;
/* this is the last field in a finger */
egalax_filter_event(td, input);
break;
case HID_DG_CONTACTCOUNT:
/* touch emulation: this is the last field in a frame */
td->first = false;
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 egalax_probe(struct hid_device *hdev, const struct hid_device_id *id)
{
int ret;
struct egalax_data *td;
struct hid_report *report;
td = kmalloc(sizeof(struct egalax_data), GFP_KERNEL);
if (!td) {
dev_err(&hdev->dev, "cannot allocate eGalax data\n");
return -ENOMEM;
}
hid_set_drvdata(hdev, td);
ret = hid_parse(hdev);
if (ret)
goto end;
ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
if (ret)
goto end;
report = hdev->report_enum[HID_FEATURE_REPORT].report_id_hash[5];
if (report) {
report->field[0]->value[0] = 2;
usbhid_submit_report(hdev, report, USB_DIR_OUT);
}
end:
if (ret)
kfree(td);
return ret;
}
static void egalax_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 egalax_devices[] = {
{ HID_USB_DEVICE(USB_VENDOR_ID_DWAV,
USB_DEVICE_ID_DWAV_EGALAX_MULTITOUCH) },
{ }
};
MODULE_DEVICE_TABLE(hid, egalax_devices);
static const struct hid_usage_id egalax_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 egalax_driver = {
.name = "egalax-touch",
.id_table = egalax_devices,
.probe = egalax_probe,
.remove = egalax_remove,
.input_mapping = egalax_input_mapping,
.input_mapped = egalax_input_mapped,
.usage_table = egalax_grabbed_usages,
.event = egalax_event,
};
static int __init egalax_init(void)
{
return hid_register_driver(&egalax_driver);
}
static void __exit egalax_exit(void)
{
hid_unregister_driver(&egalax_driver);
}
module_init(egalax_init);
module_exit(egalax_exit);
