elo.c
/*
* Elo serial touchscreen driver
*
* Copyright (c) 2004 Vojtech Pavlik
*/
/*
* 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.
*/
/*
* This driver can handle serial Elo touchscreens using either the Elo standard
* 'E271-2210' 10-byte protocol, Elo legacy 'E281A-4002' 6-byte protocol, Elo
* legacy 'E271-140' 4-byte protocol and Elo legacy 'E261-280' 3-byte protocol.
*/
#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 "Elo serial touchscreen driver"
MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
/*
* Definitions & global arrays.
*/
#define ELO_MAX_LENGTH 10
#define ELO10_PACKET_LEN 8
#define ELO10_TOUCH 0x03
#define ELO10_PRESSURE 0x80
#define ELO10_LEAD_BYTE 'U'
#define ELO10_ID_CMD 'i'
#define ELO10_TOUCH_PACKET 'T'
#define ELO10_ACK_PACKET 'A'
#define ELI10_ID_PACKET 'I'
/*
* Per-touchscreen data.
*/
struct elo {
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 csum;
unsigned char data[ELO_MAX_LENGTH];
unsigned char response[ELO10_PACKET_LEN];
char phys[32];
};
static void elo_process_data_10(struct elo *elo, unsigned char data)
{
struct input_dev *dev = elo->dev;
elo->data[elo->idx] = data;
switch (elo->idx++) {
case 0:
elo->csum = 0xaa;
if (data != ELO10_LEAD_BYTE) {
pr_debug("elo: unsynchronized data: 0x%02x\n", data);
elo->idx = 0;
}
break;
case 9:
elo->idx = 0;
if (data != elo->csum) {
pr_debug("elo: bad checksum: 0x%02x, expected 0x%02x\n",
data, elo->csum);
break;
}
if (elo->data[1] != elo->expected_packet) {
if (elo->data[1] != ELO10_TOUCH_PACKET)
pr_debug("elo: unexpected packet: 0x%02x\n",
elo->data[1]);
break;
}
if (likely(elo->data[1] == ELO10_TOUCH_PACKET)) {
input_report_abs(dev, ABS_X, (elo->data[4] << 8) | elo->data[3]);
input_report_abs(dev, ABS_Y, (elo->data[6] << 8) | elo->data[5]);
if (elo->data[2] & ELO10_PRESSURE)
input_report_abs(dev, ABS_PRESSURE,
(elo->data[8] << 8) | elo->data[7]);
input_report_key(dev, BTN_TOUCH, elo->data[2] & ELO10_TOUCH);
input_sync(dev);
} else if (elo->data[1] == ELO10_ACK_PACKET) {
if (elo->data[2] == '0')
elo->expected_packet = ELO10_TOUCH_PACKET;
complete(&elo->cmd_done);
} else {
memcpy(elo->response, &elo->data[1], ELO10_PACKET_LEN);
elo->expected_packet = ELO10_ACK_PACKET;
}
break;
}
elo->csum += data;
}
static void elo_process_data_6(struct elo *elo, unsigned char data)
{
struct input_dev *dev = elo->dev;
elo->data[elo->idx] = data;
switch (elo->idx++) {
case 0: if ((data & 0xc0) != 0xc0) elo->idx = 0; break;
case 1: if ((data & 0xc0) != 0x80) elo->idx = 0; break;
case 2: if ((data & 0xc0) != 0x40) elo->idx = 0; break;
case 3:
if (data & 0xc0) {
elo->idx = 0;
break;
}
input_report_abs(dev, ABS_X, ((elo->data[0] & 0x3f) << 6) | (elo->data[1] & 0x3f));
input_report_abs(dev, ABS_Y, ((elo->data[2] & 0x3f) << 6) | (elo->data[3] & 0x3f));
if (elo->id == 2) {
input_report_key(dev, BTN_TOUCH, 1);
input_sync(dev);
elo->idx = 0;
}
break;
case 4:
if (data) {
input_sync(dev);
elo->idx = 0;
}
break;
case 5:
if ((data & 0xf0) == 0) {
input_report_abs(dev, ABS_PRESSURE, elo->data[5]);
input_report_key(dev, BTN_TOUCH, !!elo->data[5]);
}
input_sync(dev);
elo->idx = 0;
break;
}
}
static void elo_process_data_3(struct elo *elo, unsigned char data)
{
struct input_dev *dev = elo->dev;
elo->data[elo->idx] = data;
switch (elo->idx++) {
case 0:
if ((data & 0x7f) != 0x01)
elo->idx = 0;
break;
case 2:
input_report_key(dev, BTN_TOUCH, !(elo->data[1] & 0x80));
input_report_abs(dev, ABS_X, elo->data[1]);
input_report_abs(dev, ABS_Y, elo->data[2]);
input_sync(dev);
elo->idx = 0;
break;
}
}
static irqreturn_t elo_interrupt(struct serio *serio,
unsigned char data, unsigned int flags)
{
struct elo *elo = serio_get_drvdata(serio);
switch(elo->id) {
case 0:
elo_process_data_10(elo, data);
break;
case 1:
case 2:
elo_process_data_6(elo, data);
break;
case 3:
elo_process_data_3(elo, data);
break;
}
return IRQ_HANDLED;
}
static int elo_command_10(struct elo *elo, unsigned char *packet)
{
int rc = -1;
int i;
unsigned char csum = 0xaa + ELO10_LEAD_BYTE;
mutex_lock(&elo->cmd_mutex);
serio_pause_rx(elo->serio);
elo->expected_packet = toupper(packet[0]);
init_completion(&elo->cmd_done);
serio_continue_rx(elo->serio);
if (serio_write(elo->serio, ELO10_LEAD_BYTE))
goto out;
for (i = 0; i < ELO10_PACKET_LEN; i++) {
csum += packet[i];
if (serio_write(elo->serio, packet[i]))
goto out;
}
if (serio_write(elo->serio, csum))
goto out;
wait_for_completion_timeout(&elo->cmd_done, HZ);
if (elo->expected_packet == ELO10_TOUCH_PACKET) {
/* We are back in reporting mode, the command was ACKed */
memcpy(packet, elo->response, ELO10_PACKET_LEN);
rc = 0;
}
out:
mutex_unlock(&elo->cmd_mutex);
return rc;
}
static int elo_setup_10(struct elo *elo)
{
static const char *elo_types[] = { "Accu", "Dura", "Intelli", "Carroll" };
struct input_dev *dev = elo->dev;
unsigned char packet[ELO10_PACKET_LEN] = { ELO10_ID_CMD };
if (elo_command_10(elo, packet))
return -1;
dev->id.version = (packet[5] << 8) | packet[4];
input_set_abs_params(dev, ABS_X, 96, 4000, 0, 0);
input_set_abs_params(dev, ABS_Y, 96, 4000, 0, 0);
if (packet[3] & ELO10_PRESSURE)
input_set_abs_params(dev, ABS_PRESSURE, 0, 255, 0, 0);
printk(KERN_INFO "elo: %sTouch touchscreen, fw: %02x.%02x, "
"features: %x02x, controller: 0x%02x\n",
elo_types[(packet[1] -'0') & 0x03],
packet[5], packet[4], packet[3], packet[7]);
return 0;
}
/*
* elo_disconnect() is the opposite of elo_connect()
*/
static void elo_disconnect(struct serio *serio)
{
struct elo *elo = serio_get_drvdata(serio);
input_get_device(elo->dev);
input_unregister_device(elo->dev);
serio_close(serio);
serio_set_drvdata(serio, NULL);
input_put_device(elo->dev);
kfree(elo);
}
/*
* elo_connect() is the routine that is called when someone adds a
* new serio device that supports Gunze protocol and registers it as
* an input device.
*/
static int elo_connect(struct serio *serio, struct serio_driver *drv)
{
struct elo *elo;
struct input_dev *input_dev;
int err;
elo = kzalloc(sizeof(struct elo), GFP_KERNEL);
input_dev = input_allocate_device();
if (!elo || !input_dev) {
err = -ENOMEM;
goto fail1;
}
elo->serio = serio;
elo->id = serio->id.id;
elo->dev = input_dev;
elo->expected_packet = ELO10_TOUCH_PACKET;
mutex_init(&elo->cmd_mutex);
init_completion(&elo->cmd_done);
snprintf(elo->phys, sizeof(elo->phys), "%s/input0", serio->phys);
input_dev->name = "Elo Serial TouchScreen";
input_dev->phys = elo->phys;
input_dev->id.bustype = BUS_RS232;
input_dev->id.vendor = SERIO_ELO;
input_dev->id.product = elo->id;
input_dev->id.version = 0x0100;
input_dev->dev.parent = &serio->dev;
input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
input_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH);
serio_set_drvdata(serio, elo);
err = serio_open(serio, drv);
if (err)
goto fail2;
switch (elo->id) {
case 0: /* 10-byte protocol */
if (elo_setup_10(elo))
goto fail3;
break;
case 1: /* 6-byte protocol */
input_set_abs_params(input_dev, ABS_PRESSURE, 0, 15, 0, 0);
case 2: /* 4-byte protocol */
input_set_abs_params(input_dev, ABS_X, 96, 4000, 0, 0);
input_set_abs_params(input_dev, ABS_Y, 96, 4000, 0, 0);
break;
case 3: /* 3-byte protocol */
input_set_abs_params(input_dev, ABS_X, 0, 255, 0, 0);
input_set_abs_params(input_dev, ABS_Y, 0, 255, 0, 0);
break;
}
err = input_register_device(elo->dev);
if (err)
goto fail3;
return 0;
fail3: serio_close(serio);
fail2: serio_set_drvdata(serio, NULL);
fail1: input_free_device(input_dev);
kfree(elo);
return err;
}
/*
* The serio driver structure.
*/
static struct serio_device_id elo_serio_ids[] = {
{
.type = SERIO_RS232,
.proto = SERIO_ELO,
.id = SERIO_ANY,
.extra = SERIO_ANY,
},
{ 0 }
};
MODULE_DEVICE_TABLE(serio, elo_serio_ids);
static struct serio_driver elo_drv = {
.driver = {
.name = "elo",
},
.description = DRIVER_DESC,
.id_table = elo_serio_ids,
.interrupt = elo_interrupt,
.connect = elo_connect,
.disconnect = elo_disconnect,
};
/*
* The functions for inserting/removing us as a module.
*/
static int __init elo_init(void)
{
return serio_register_driver(&elo_drv);
}
static void __exit elo_exit(void)
{
serio_unregister_driver(&elo_drv);
}
module_init(elo_init);
module_exit(elo_exit);