/*
* Wacom W8001 penabled serial touchscreen driver
*
* Copyright (c) 2008 Jaya Kumar
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file COPYING in the main directory of this archive for
* more details.
*
* Layout based on Elo serial touchscreen driver by Vojtech Pavlik
*/
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/input.h>
#include <linux/serio.h>
#include <linux/init.h>
#include <linux/ctype.h>
#define DRIVER_DESC "Wacom W8001 serial touchscreen driver"
MODULE_AUTHOR("Jaya Kumar <jayakumar.lkml@gmail.com>");
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
/*
* Definitions & global arrays.
*/
#define W8001_MAX_LENGTH 11
#define W8001_PACKET_LEN 11
#define W8001_LEAD_MASK 0x80
#define W8001_LEAD_BYTE 0x80
#define W8001_TAB_MASK 0x40
#define W8001_TAB_BYTE 0x40
#define W8001_QUERY_PACKET 0x20
struct w8001_coord {
u8 rdy;
u8 tsw;
u8 f1;
u8 f2;
u16 x;
u16 y;
u16 pen_pressure;
u8 tilt_x;
u8 tilt_y;
};
/*
* Per-touchscreen data.
*/
struct w8001 {
struct input_dev *dev;
struct serio *serio;
struct mutex cmd_mutex;
struct completion cmd_done;
int id;
int idx;
unsigned char expected_packet;
unsigned char data[W8001_MAX_LENGTH];
unsigned char response[W8001_PACKET_LEN];
char phys[32];
};
static int parse_data(u8 *data, struct w8001_coord *coord)
{
coord->rdy = data[0] & 0x20;
coord->tsw = data[0] & 0x01;
coord->f1 = data[0] & 0x02;
coord->f2 = data[0] & 0x04;
coord->x = (data[1] & 0x7F) << 9;
coord->x |= (data[2] & 0x7F) << 2;
coord->x |= (data[6] & 0x60) >> 5;
coord->y = (data[3] & 0x7F) << 9;
coord->y |= (data[4] & 0x7F) << 2;
coord->y |= (data[6] & 0x18) >> 3;
coord->pen_pressure = data[5] & 0x7F;
coord->pen_pressure |= (data[6] & 0x07) << 7 ;
coord->tilt_x = data[7] & 0x7F;
coord->tilt_y = data[8] & 0x7F;
return 0;
}
static void w8001_process_data(struct w8001 *w8001, unsigned char data)
{
struct input_dev *dev = w8001->dev;
u8 tmp;
struct w8001_coord coord;
w8001->data[w8001->idx] = data;
switch (w8001->idx++) {
case 0:
if ((data & W8001_LEAD_MASK) != W8001_LEAD_BYTE) {
pr_debug("w8001: unsynchronized data: 0x%02x\n", data);
w8001->idx = 0;
}
break;
case 8:
tmp = w8001->data[0] & W8001_TAB_MASK;
if (unlikely(tmp == W8001_TAB_BYTE))
break;
w8001->idx = 0;
memset(&coord, 0, sizeof(coord));
parse_data(w8001->data, &coord);
input_report_abs(dev, ABS_X, coord.x);
input_report_abs(dev, ABS_Y, coord.y);
input_report_abs(dev, ABS_PRESSURE, coord.pen_pressure);
input_report_key(dev, BTN_TOUCH, coord.tsw);
input_sync(dev);
break;
case 10:
w8001->idx = 0;
memcpy(w8001->response, &w8001->data, W8001_PACKET_LEN);
w8001->expected_packet = W8001_QUERY_PACKET;
complete(&w8001->cmd_done);
break;
}
}
static irqreturn_t w8001_interrupt(struct serio *serio,
unsigned char data, unsigned int flags)
{
struct w8001 *w8001 = serio_get_drvdata(serio);
w8001_process_data(w8001, data);
return IRQ_HANDLED;
}
static int w8001_async_command(struct w8001 *w8001, unsigned char *packet,
int len)
{
int rc = -1;
int i;
mutex_lock(&w8001->cmd_mutex);
for (i = 0; i < len; i++) {
if (serio_write(w8001->serio, packet[i]))
goto out;
}
rc = 0;
out:
mutex_unlock(&w8001->cmd_mutex);
return rc;
}
static int w8001_command(struct w8001 *w8001, unsigned char *packet, int len)
{
int rc = -1;
int i;
mutex_lock(&w8001->cmd_mutex);
serio_pause_rx(w8001->serio);
init_completion(&w8001->cmd_done);
serio_continue_rx(w8001->serio);
for (i = 0; i < len; i++) {
if (serio_write(w8001->serio, packet[i]))
goto out;
}
wait_for_completion_timeout(&w8001->cmd_done, HZ);
if (w8001->expected_packet == W8001_QUERY_PACKET) {
/* We are back in reporting mode, the query was ACKed */
memcpy(packet, w8001->response, W8001_PACKET_LEN);
rc = 0;
}
out:
mutex_unlock(&w8001->cmd_mutex);
return rc;
}
static int w8001_setup(struct w8001 *w8001)
{
struct w8001_coord coord;
struct input_dev *dev = w8001->dev;
unsigned char start[1] = { '1' };
unsigned char query[11] = { '*' };
if (w8001_command(w8001, query, 1))
return -1;
memset(&coord, 0, sizeof(coord));
parse_data(query, &coord);
input_set_abs_params(dev, ABS_X, 0, coord.x, 0, 0);
input_set_abs_params(dev, ABS_Y, 0, coord.y, 0, 0);
input_set_abs_params(dev, ABS_PRESSURE, 0, coord.pen_pressure, 0, 0);
input_set_abs_params(dev, ABS_TILT_X, 0, coord.tilt_x, 0, 0);
input_set_abs_params(dev, ABS_TILT_Y, 0, coord.tilt_y, 0, 0);
if (w8001_async_command(w8001, start, 1))
return -1;
return 0;
}
/*
* w8001_disconnect() is the opposite of w8001_connect()
*/
static void w8001_disconnect(struct serio *serio)
{
struct w8001 *w8001 = serio_get_drvdata(serio);
input_get_device(w8001->dev);
input_unregister_device(w8001->dev);
serio_close(serio);
serio_set_drvdata(serio, NULL);
input_put_device(w8001->dev);
kfree(w8001);
}
/*
* w8001_connect() is the routine that is called when someone adds a
* new serio device that supports the w8001 protocol and registers it as
* an input device.
*/
static int w8001_connect(struct serio *serio, struct serio_driver *drv)
{
struct w8001 *w8001;
struct input_dev *input_dev;
int err;
w8001 = kzalloc(sizeof(struct w8001), GFP_KERNEL);
input_dev = input_allocate_device();
if (!w8001 || !input_dev) {
err = -ENOMEM;
goto fail1;
}
w8001->serio = serio;
w8001->id = serio->id.id;
w8001->dev = input_dev;
mutex_init(&w8001->cmd_mutex);
init_completion(&w8001->cmd_done);
snprintf(w8001->phys, sizeof(w8001->phys), "%s/input0", serio->phys);
input_dev->name = "Wacom W8001 Penabled Serial TouchScreen";
input_dev->phys = w8001->phys;
input_dev->id.bustype = BUS_RS232;
input_dev->id.vendor = SERIO_W8001;
input_dev->id.product = w8001->id;
input_dev->id.version = 0x0100;
input_dev->dev.parent = &serio->dev;
input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
serio_set_drvdata(serio, w8001);
err = serio_open(serio, drv);
if (err)
goto fail2;
if (w8001_setup(w8001))
goto fail3;
err = input_register_device(w8001->dev);
if (err)
goto fail3;
return 0;
fail3:
serio_close(serio);
fail2:
serio_set_drvdata(serio, NULL);
fail1:
input_free_device(input_dev);
kfree(w8001);
return err;
}
static struct serio_device_id w8001_serio_ids[] = {
{
.type = SERIO_RS232,
.proto = SERIO_W8001,
.id = SERIO_ANY,
.extra = SERIO_ANY,
},
{ 0 }
};
MODULE_DEVICE_TABLE(serio, w8001_serio_ids);
static struct serio_driver w8001_drv = {
.driver = {
.name = "w8001",
},
.description = DRIVER_DESC,
.id_table = w8001_serio_ids,
.interrupt = w8001_interrupt,
.connect = w8001_connect,
.disconnect = w8001_disconnect,
};
static int __init w8001_init(void)
{
return serio_register_driver(&w8001_drv);
}
static void __exit w8001_exit(void)
{
serio_unregister_driver(&w8001_drv);
}
module_init(w8001_init);
module_exit(w8001_exit);
