linux/drivers/hwmon/ams/ams-input.c
Dmitry Torokhov 0a02002268 hwmon: (ams) Fix permissions on 'joystick' module parameter
We should not allow writes to the 'joystick' module parameters since
writing there will not trigger creation of the input device. Disable
writes since we provide alternative way of enabling input device via
AMS device's sysfs attribute.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-10-17 17:51:12 +02:00

149 lines
3.3 KiB
C

/*
* Apple Motion Sensor driver (joystick emulation)
*
* Copyright (C) 2005 Stelian Pop (stelian@popies.net)
* Copyright (C) 2006 Michael Hanselmann (linux-kernel@hansmi.ch)
*
* 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/module.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/delay.h>
#include "ams.h"
static unsigned int joystick;
module_param(joystick, bool, S_IRUGO);
MODULE_PARM_DESC(joystick, "Enable the input class device on module load");
static unsigned int invert;
module_param(invert, bool, S_IWUSR | S_IRUGO);
MODULE_PARM_DESC(invert, "Invert input data on X and Y axis");
static void ams_idev_poll(struct input_polled_dev *dev)
{
struct input_dev *idev = dev->input;
s8 x, y, z;
mutex_lock(&ams_info.lock);
ams_sensors(&x, &y, &z);
x -= ams_info.xcalib;
y -= ams_info.ycalib;
z -= ams_info.zcalib;
input_report_abs(idev, ABS_X, invert ? -x : x);
input_report_abs(idev, ABS_Y, invert ? -y : y);
input_report_abs(idev, ABS_Z, z);
input_sync(idev);
mutex_unlock(&ams_info.lock);
}
/* Call with ams_info.lock held! */
static void ams_input_enable(void)
{
struct input_dev *input;
s8 x, y, z;
if (ams_info.idev)
return;
ams_sensors(&x, &y, &z);
ams_info.xcalib = x;
ams_info.ycalib = y;
ams_info.zcalib = z;
ams_info.idev = input_allocate_polled_device();
if (!ams_info.idev)
return;
ams_info.idev->poll = ams_idev_poll;
ams_info.idev->poll_interval = 25;
input = ams_info.idev->input;
input->name = "Apple Motion Sensor";
input->id.bustype = ams_info.bustype;
input->id.vendor = 0;
input->dev.parent = &ams_info.of_dev->dev;
input_set_abs_params(input, ABS_X, -50, 50, 3, 0);
input_set_abs_params(input, ABS_Y, -50, 50, 3, 0);
input_set_abs_params(input, ABS_Z, -50, 50, 3, 0);
set_bit(EV_ABS, input->evbit);
set_bit(EV_KEY, input->evbit);
set_bit(BTN_TOUCH, input->keybit);
if (input_register_polled_device(ams_info.idev)) {
input_free_polled_device(ams_info.idev);
ams_info.idev = NULL;
return;
}
}
/* Call with ams_info.lock held! */
static void ams_input_disable(void)
{
if (ams_info.idev) {
input_unregister_polled_device(ams_info.idev);
input_free_polled_device(ams_info.idev);
ams_info.idev = NULL;
}
}
static ssize_t ams_input_show_joystick(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sprintf(buf, "%d\n", joystick);
}
static ssize_t ams_input_store_joystick(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
if (sscanf(buf, "%d\n", &joystick) != 1)
return -EINVAL;
mutex_lock(&ams_info.lock);
if (joystick)
ams_input_enable();
else
ams_input_disable();
mutex_unlock(&ams_info.lock);
return count;
}
static DEVICE_ATTR(joystick, S_IRUGO | S_IWUSR,
ams_input_show_joystick, ams_input_store_joystick);
/* Call with ams_info.lock held! */
int ams_input_init(void)
{
int result;
result = device_create_file(&ams_info.of_dev->dev, &dev_attr_joystick);
if (!result && joystick)
ams_input_enable();
return result;
}
/* Call with ams_info.lock held! */
void ams_input_exit(void)
{
ams_input_disable();
device_remove_file(&ams_info.of_dev->dev, &dev_attr_joystick);
}