mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-21 08:19:28 +00:00
![Dan Carpenter](/assets/img/avatar_default.png)
We didn't check input_allocate_device() for failures so it could lead to
a NULL deref.
Fixes: 6b0f8f9c52
('Input: add eGalaxTouch serial touchscreen driver')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
194 lines
4.5 KiB
C
194 lines
4.5 KiB
C
/*
|
|
* EETI Egalax serial touchscreen driver
|
|
*
|
|
* Copyright (c) 2015 Zoltán Böszörményi <zboszor@pr.hu>
|
|
*
|
|
* based on the
|
|
*
|
|
* Hampshire serial touchscreen driver (Copyright (c) 2010 Adam Bennett)
|
|
*/
|
|
|
|
/*
|
|
* This program is free software; you can redistribute it and/or modify it
|
|
* under the terms of the GNU General Public License version 2 as published by
|
|
* the Free Software Foundation.
|
|
*/
|
|
|
|
#include <linux/errno.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/input.h>
|
|
#include <linux/serio.h>
|
|
|
|
#define DRIVER_DESC "EETI Egalax serial touchscreen driver"
|
|
|
|
/*
|
|
* Definitions & global arrays.
|
|
*/
|
|
|
|
#define EGALAX_FORMAT_MAX_LENGTH 6
|
|
#define EGALAX_FORMAT_START_BIT BIT(7)
|
|
#define EGALAX_FORMAT_PRESSURE_BIT BIT(6)
|
|
#define EGALAX_FORMAT_TOUCH_BIT BIT(0)
|
|
#define EGALAX_FORMAT_RESOLUTION_MASK 0x06
|
|
|
|
#define EGALAX_MIN_XC 0
|
|
#define EGALAX_MAX_XC 0x4000
|
|
#define EGALAX_MIN_YC 0
|
|
#define EGALAX_MAX_YC 0x4000
|
|
|
|
/*
|
|
* Per-touchscreen data.
|
|
*/
|
|
struct egalax {
|
|
struct input_dev *input;
|
|
struct serio *serio;
|
|
int idx;
|
|
u8 data[EGALAX_FORMAT_MAX_LENGTH];
|
|
char phys[32];
|
|
};
|
|
|
|
static void egalax_process_data(struct egalax *egalax)
|
|
{
|
|
struct input_dev *dev = egalax->input;
|
|
u8 *data = egalax->data;
|
|
u16 x, y;
|
|
u8 shift;
|
|
u8 mask;
|
|
|
|
shift = 3 - ((data[0] & EGALAX_FORMAT_RESOLUTION_MASK) >> 1);
|
|
mask = 0xff >> (shift + 1);
|
|
|
|
x = (((u16)(data[1] & mask) << 7) | (data[2] & 0x7f)) << shift;
|
|
y = (((u16)(data[3] & mask) << 7) | (data[4] & 0x7f)) << shift;
|
|
|
|
input_report_key(dev, BTN_TOUCH, data[0] & EGALAX_FORMAT_TOUCH_BIT);
|
|
input_report_abs(dev, ABS_X, x);
|
|
input_report_abs(dev, ABS_Y, y);
|
|
input_sync(dev);
|
|
}
|
|
|
|
static irqreturn_t egalax_interrupt(struct serio *serio,
|
|
unsigned char data, unsigned int flags)
|
|
{
|
|
struct egalax *egalax = serio_get_drvdata(serio);
|
|
int pkt_len;
|
|
|
|
egalax->data[egalax->idx++] = data;
|
|
|
|
if (likely(egalax->data[0] & EGALAX_FORMAT_START_BIT)) {
|
|
pkt_len = egalax->data[0] & EGALAX_FORMAT_PRESSURE_BIT ? 6 : 5;
|
|
if (pkt_len == egalax->idx) {
|
|
egalax_process_data(egalax);
|
|
egalax->idx = 0;
|
|
}
|
|
} else {
|
|
dev_dbg(&serio->dev, "unknown/unsynchronized data: %x\n",
|
|
egalax->data[0]);
|
|
egalax->idx = 0;
|
|
}
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
/*
|
|
* egalax_connect() is the routine that is called when someone adds a
|
|
* new serio device that supports egalax protocol and registers it as
|
|
* an input device. This is usually accomplished using inputattach.
|
|
*/
|
|
static int egalax_connect(struct serio *serio, struct serio_driver *drv)
|
|
{
|
|
struct egalax *egalax;
|
|
struct input_dev *input_dev;
|
|
int error;
|
|
|
|
egalax = kzalloc(sizeof(struct egalax), GFP_KERNEL);
|
|
input_dev = input_allocate_device();
|
|
if (!egalax || !input_dev) {
|
|
error = -ENOMEM;
|
|
goto err_free_mem;
|
|
}
|
|
|
|
egalax->serio = serio;
|
|
egalax->input = input_dev;
|
|
snprintf(egalax->phys, sizeof(egalax->phys),
|
|
"%s/input0", serio->phys);
|
|
|
|
input_dev->name = "EETI eGalaxTouch Serial TouchScreen";
|
|
input_dev->phys = egalax->phys;
|
|
input_dev->id.bustype = BUS_RS232;
|
|
input_dev->id.vendor = SERIO_EGALAX;
|
|
input_dev->id.product = 0;
|
|
input_dev->id.version = 0x0001;
|
|
input_dev->dev.parent = &serio->dev;
|
|
|
|
input_set_capability(input_dev, EV_KEY, BTN_TOUCH);
|
|
input_set_abs_params(input_dev, ABS_X,
|
|
EGALAX_MIN_XC, EGALAX_MAX_XC, 0, 0);
|
|
input_set_abs_params(input_dev, ABS_Y,
|
|
EGALAX_MIN_YC, EGALAX_MAX_YC, 0, 0);
|
|
|
|
serio_set_drvdata(serio, egalax);
|
|
|
|
error = serio_open(serio, drv);
|
|
if (error)
|
|
goto err_reset_drvdata;
|
|
|
|
error = input_register_device(input_dev);
|
|
if (error)
|
|
goto err_close_serio;
|
|
|
|
return 0;
|
|
|
|
err_close_serio:
|
|
serio_close(serio);
|
|
err_reset_drvdata:
|
|
serio_set_drvdata(serio, NULL);
|
|
err_free_mem:
|
|
input_free_device(input_dev);
|
|
kfree(egalax);
|
|
return error;
|
|
}
|
|
|
|
static void egalax_disconnect(struct serio *serio)
|
|
{
|
|
struct egalax *egalax = serio_get_drvdata(serio);
|
|
|
|
serio_close(serio);
|
|
serio_set_drvdata(serio, NULL);
|
|
input_unregister_device(egalax->input);
|
|
kfree(egalax);
|
|
}
|
|
|
|
/*
|
|
* The serio driver structure.
|
|
*/
|
|
|
|
static const struct serio_device_id egalax_serio_ids[] = {
|
|
{
|
|
.type = SERIO_RS232,
|
|
.proto = SERIO_EGALAX,
|
|
.id = SERIO_ANY,
|
|
.extra = SERIO_ANY,
|
|
},
|
|
{ 0 }
|
|
};
|
|
|
|
MODULE_DEVICE_TABLE(serio, egalax_serio_ids);
|
|
|
|
static struct serio_driver egalax_drv = {
|
|
.driver = {
|
|
.name = "egalax",
|
|
},
|
|
.description = DRIVER_DESC,
|
|
.id_table = egalax_serio_ids,
|
|
.interrupt = egalax_interrupt,
|
|
.connect = egalax_connect,
|
|
.disconnect = egalax_disconnect,
|
|
};
|
|
module_serio_driver(egalax_drv);
|
|
|
|
MODULE_AUTHOR("Zoltán Böszörményi <zboszor@pr.hu>");
|
|
MODULE_DESCRIPTION(DRIVER_DESC);
|
|
MODULE_LICENSE("GPL v2");
|