mirror of
https://github.com/torvalds/linux.git
synced 2024-10-30 16:51:45 +00:00
3e24e2b5ae
This is a driver for Zhen Hua PPM-4CH RC transmitter (commonly used in cheap Ready To Fly RC helicopters by Walkera) which using "Zhen Hua 5-byte protocol" for using them as a four axis joystick via serial port. Transmitter connected to serial port (19200 8N1) sending periodically 5 bytes where first byte is for synchronization and next four bytes are values of axis. Signed-off-by: Martin Kebert <gkmarty@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
244 lines
6.0 KiB
C
244 lines
6.0 KiB
C
/*
|
|
* derived from "twidjoy.c"
|
|
*
|
|
* Copyright (c) 2008 Martin Kebert
|
|
* Copyright (c) 2001 Arndt Schoenewald
|
|
* Copyright (c) 2000-2001 Vojtech Pavlik
|
|
* Copyright (c) 2000 Mark Fletcher
|
|
*
|
|
*/
|
|
|
|
/*
|
|
* Driver to use 4CH RC transmitter using Zhen Hua 5-byte protocol (Walkera Lama,
|
|
* EasyCopter etc.) as a joystick under Linux.
|
|
*
|
|
* RC transmitters using Zhen Hua 5-byte protocol are cheap four channels
|
|
* transmitters for control a RC planes or RC helicopters with possibility to
|
|
* connect on a serial port.
|
|
* Data coming from transmitter is in this order:
|
|
* 1. byte = synchronisation byte
|
|
* 2. byte = X axis
|
|
* 3. byte = Y axis
|
|
* 4. byte = RZ axis
|
|
* 5. byte = Z axis
|
|
* (and this is repeated)
|
|
*
|
|
* For questions or feedback regarding this driver module please contact:
|
|
* Martin Kebert <gkmarty@gmail.com> - but I am not a C-programmer nor kernel
|
|
* coder :-(
|
|
*/
|
|
|
|
/*
|
|
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/input.h>
|
|
#include <linux/serio.h>
|
|
#include <linux/init.h>
|
|
|
|
#define DRIVER_DESC "RC transmitter with 5-byte Zhen Hua protocol joystick driver"
|
|
|
|
MODULE_DESCRIPTION(DRIVER_DESC);
|
|
MODULE_LICENSE("GPL");
|
|
|
|
/*
|
|
* Constants.
|
|
*/
|
|
|
|
#define ZHENHUA_MAX_LENGTH 5
|
|
|
|
/*
|
|
* Zhen Hua data.
|
|
*/
|
|
|
|
struct zhenhua {
|
|
struct input_dev *dev;
|
|
int idx;
|
|
unsigned char data[ZHENHUA_MAX_LENGTH];
|
|
char phys[32];
|
|
};
|
|
|
|
|
|
/* bits in all incoming bytes needs to be "reversed" */
|
|
static int zhenhua_bitreverse(int x)
|
|
{
|
|
x = ((x & 0xaa) >> 1) | ((x & 0x55) << 1);
|
|
x = ((x & 0xcc) >> 2) | ((x & 0x33) << 2);
|
|
x = ((x & 0xf0) >> 4) | ((x & 0x0f) << 4);
|
|
return x;
|
|
}
|
|
|
|
/*
|
|
* zhenhua_process_packet() decodes packets the driver receives from the
|
|
* RC transmitter. It updates the data accordingly.
|
|
*/
|
|
|
|
static void zhenhua_process_packet(struct zhenhua *zhenhua)
|
|
{
|
|
struct input_dev *dev = zhenhua->dev;
|
|
unsigned char *data = zhenhua->data;
|
|
|
|
input_report_abs(dev, ABS_Y, data[1]);
|
|
input_report_abs(dev, ABS_X, data[2]);
|
|
input_report_abs(dev, ABS_RZ, data[3]);
|
|
input_report_abs(dev, ABS_Z, data[4]);
|
|
|
|
input_sync(dev);
|
|
}
|
|
|
|
/*
|
|
* zhenhua_interrupt() is called by the low level driver when characters
|
|
* are ready for us. We then buffer them for further processing, or call the
|
|
* packet processing routine.
|
|
*/
|
|
|
|
static irqreturn_t zhenhua_interrupt(struct serio *serio, unsigned char data, unsigned int flags)
|
|
{
|
|
struct zhenhua *zhenhua = serio_get_drvdata(serio);
|
|
|
|
/* All Zhen Hua packets are 5 bytes. The fact that the first byte
|
|
* is allways 0xf7 and all others are in range 0x32 - 0xc8 (50-200)
|
|
* can be used to check and regain sync. */
|
|
|
|
if (data == 0xef)
|
|
zhenhua->idx = 0; /* this byte starts a new packet */
|
|
else if (zhenhua->idx == 0)
|
|
return IRQ_HANDLED; /* wrong MSB -- ignore this byte */
|
|
|
|
if (zhenhua->idx < ZHENHUA_MAX_LENGTH)
|
|
zhenhua->data[zhenhua->idx++] = zhenhua_bitreverse(data);
|
|
|
|
if (zhenhua->idx == ZHENHUA_MAX_LENGTH) {
|
|
zhenhua_process_packet(zhenhua);
|
|
zhenhua->idx = 0;
|
|
}
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
/*
|
|
* zhenhua_disconnect() is the opposite of zhenhua_connect()
|
|
*/
|
|
|
|
static void zhenhua_disconnect(struct serio *serio)
|
|
{
|
|
struct zhenhua *zhenhua = serio_get_drvdata(serio);
|
|
|
|
serio_close(serio);
|
|
serio_set_drvdata(serio, NULL);
|
|
input_unregister_device(zhenhua->dev);
|
|
kfree(zhenhua);
|
|
}
|
|
|
|
/*
|
|
* zhenhua_connect() is the routine that is called when someone adds a
|
|
* new serio device. It looks for the Twiddler, and if found, registers
|
|
* it as an input device.
|
|
*/
|
|
|
|
static int zhenhua_connect(struct serio *serio, struct serio_driver *drv)
|
|
{
|
|
struct zhenhua *zhenhua;
|
|
struct input_dev *input_dev;
|
|
int err = -ENOMEM;
|
|
|
|
zhenhua = kzalloc(sizeof(struct zhenhua), GFP_KERNEL);
|
|
input_dev = input_allocate_device();
|
|
if (!zhenhua || !input_dev)
|
|
goto fail1;
|
|
|
|
zhenhua->dev = input_dev;
|
|
snprintf(zhenhua->phys, sizeof(zhenhua->phys), "%s/input0", serio->phys);
|
|
|
|
input_dev->name = "Zhen Hua 5-byte device";
|
|
input_dev->phys = zhenhua->phys;
|
|
input_dev->id.bustype = BUS_RS232;
|
|
input_dev->id.vendor = SERIO_ZHENHUA;
|
|
input_dev->id.product = 0x0001;
|
|
input_dev->id.version = 0x0100;
|
|
input_dev->dev.parent = &serio->dev;
|
|
|
|
input_dev->evbit[0] = BIT(EV_ABS);
|
|
input_set_abs_params(input_dev, ABS_X, 50, 200, 0, 0);
|
|
input_set_abs_params(input_dev, ABS_Y, 50, 200, 0, 0);
|
|
input_set_abs_params(input_dev, ABS_Z, 50, 200, 0, 0);
|
|
input_set_abs_params(input_dev, ABS_RZ, 50, 200, 0, 0);
|
|
|
|
serio_set_drvdata(serio, zhenhua);
|
|
|
|
err = serio_open(serio, drv);
|
|
if (err)
|
|
goto fail2;
|
|
|
|
err = input_register_device(zhenhua->dev);
|
|
if (err)
|
|
goto fail3;
|
|
|
|
return 0;
|
|
|
|
fail3: serio_close(serio);
|
|
fail2: serio_set_drvdata(serio, NULL);
|
|
fail1: input_free_device(input_dev);
|
|
kfree(zhenhua);
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* The serio driver structure.
|
|
*/
|
|
|
|
static struct serio_device_id zhenhua_serio_ids[] = {
|
|
{
|
|
.type = SERIO_RS232,
|
|
.proto = SERIO_ZHENHUA,
|
|
.id = SERIO_ANY,
|
|
.extra = SERIO_ANY,
|
|
},
|
|
{ 0 }
|
|
};
|
|
|
|
MODULE_DEVICE_TABLE(serio, zhenhua_serio_ids);
|
|
|
|
static struct serio_driver zhenhua_drv = {
|
|
.driver = {
|
|
.name = "zhenhua",
|
|
},
|
|
.description = DRIVER_DESC,
|
|
.id_table = zhenhua_serio_ids,
|
|
.interrupt = zhenhua_interrupt,
|
|
.connect = zhenhua_connect,
|
|
.disconnect = zhenhua_disconnect,
|
|
};
|
|
|
|
/*
|
|
* The functions for inserting/removing us as a module.
|
|
*/
|
|
|
|
static int __init zhenhua_init(void)
|
|
{
|
|
return serio_register_driver(&zhenhua_drv);
|
|
}
|
|
|
|
static void __exit zhenhua_exit(void)
|
|
{
|
|
serio_unregister_driver(&zhenhua_drv);
|
|
}
|
|
|
|
module_init(zhenhua_init);
|
|
module_exit(zhenhua_exit);
|