145 lines
3.7 KiB
C
145 lines
3.7 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* Force feedback support for Logitech Flight System G940
|
|
*
|
|
* Copyright (c) 2009 Gary Stein <LordCnidarian@gmail.com>
|
|
*/
|
|
|
|
/*
|
|
*/
|
|
|
|
|
|
#include <linux/input.h>
|
|
#include <linux/hid.h>
|
|
|
|
#include "hid-lg.h"
|
|
|
|
/*
|
|
* G940 Theory of Operation (from experimentation)
|
|
*
|
|
* There are 63 fields (only 3 of them currently used)
|
|
* 0 - seems to be command field
|
|
* 1 - 30 deal with the x axis
|
|
* 31 -60 deal with the y axis
|
|
*
|
|
* Field 1 is x axis constant force
|
|
* Field 31 is y axis constant force
|
|
*
|
|
* other interesting fields 1,2,3,4 on x axis
|
|
* (same for 31,32,33,34 on y axis)
|
|
*
|
|
* 0 0 127 127 makes the joystick autocenter hard
|
|
*
|
|
* 127 0 127 127 makes the joystick loose on the right,
|
|
* but stops all movemnt left
|
|
*
|
|
* -127 0 -127 -127 makes the joystick loose on the left,
|
|
* but stops all movement right
|
|
*
|
|
* 0 0 -127 -127 makes the joystick rattle very hard
|
|
*
|
|
* I'm sure these are effects that I don't know enough about them
|
|
*/
|
|
|
|
struct lg3ff_device {
|
|
struct hid_report *report;
|
|
};
|
|
|
|
static int hid_lg3ff_play(struct input_dev *dev, void *data,
|
|
struct ff_effect *effect)
|
|
{
|
|
struct hid_device *hid = input_get_drvdata(dev);
|
|
struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
|
|
struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
|
|
int x, y;
|
|
|
|
/*
|
|
* Available values in the field should always be 63, but we only use up to
|
|
* 35. Instead, clear the entire area, however big it is.
|
|
*/
|
|
memset(report->field[0]->value, 0,
|
|
sizeof(__s32) * report->field[0]->report_count);
|
|
|
|
switch (effect->type) {
|
|
case FF_CONSTANT:
|
|
/*
|
|
* Already clamped in ff_memless
|
|
* 0 is center (different then other logitech)
|
|
*/
|
|
x = effect->u.ramp.start_level;
|
|
y = effect->u.ramp.end_level;
|
|
|
|
/* send command byte */
|
|
report->field[0]->value[0] = 0x51;
|
|
|
|
/*
|
|
* Sign backwards from other Force3d pro
|
|
* which get recast here in two's complement 8 bits
|
|
*/
|
|
report->field[0]->value[1] = (unsigned char)(-x);
|
|
report->field[0]->value[31] = (unsigned char)(-y);
|
|
|
|
hid_hw_request(hid, report, HID_REQ_SET_REPORT);
|
|
break;
|
|
}
|
|
return 0;
|
|
}
|
|
static void hid_lg3ff_set_autocenter(struct input_dev *dev, u16 magnitude)
|
|
{
|
|
struct hid_device *hid = input_get_drvdata(dev);
|
|
struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
|
|
struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
|
|
|
|
/*
|
|
* Auto Centering probed from device
|
|
* NOTE: deadman's switch on G940 must be covered
|
|
* for effects to work
|
|
*/
|
|
report->field[0]->value[0] = 0x51;
|
|
report->field[0]->value[1] = 0x00;
|
|
report->field[0]->value[2] = 0x00;
|
|
report->field[0]->value[3] = 0x7F;
|
|
report->field[0]->value[4] = 0x7F;
|
|
report->field[0]->value[31] = 0x00;
|
|
report->field[0]->value[32] = 0x00;
|
|
report->field[0]->value[33] = 0x7F;
|
|
report->field[0]->value[34] = 0x7F;
|
|
|
|
hid_hw_request(hid, report, HID_REQ_SET_REPORT);
|
|
}
|
|
|
|
|
|
static const signed short ff3_joystick_ac[] = {
|
|
FF_CONSTANT,
|
|
FF_AUTOCENTER,
|
|
-1
|
|
};
|
|
|
|
int lg3ff_init(struct hid_device *hid)
|
|
{
|
|
struct hid_input *hidinput = list_entry(hid->inputs.next, struct hid_input, list);
|
|
struct input_dev *dev = hidinput->input;
|
|
const signed short *ff_bits = ff3_joystick_ac;
|
|
int error;
|
|
int i;
|
|
|
|
/* Check that the report looks ok */
|
|
if (!hid_validate_values(hid, HID_OUTPUT_REPORT, 0, 0, 35))
|
|
return -ENODEV;
|
|
|
|
/* Assume single fixed device G940 */
|
|
for (i = 0; ff_bits[i] >= 0; i++)
|
|
set_bit(ff_bits[i], dev->ffbit);
|
|
|
|
error = input_ff_create_memless(dev, NULL, hid_lg3ff_play);
|
|
if (error)
|
|
return error;
|
|
|
|
if (test_bit(FF_AUTOCENTER, dev->ffbit))
|
|
dev->ff->set_autocenter = hid_lg3ff_set_autocenter;
|
|
|
|
hid_info(hid, "Force feedback for Logitech Flight System G940 by Gary Stein <LordCnidarian@gmail.com>\n");
|
|
return 0;
|
|
}
|
|
|