penmount.c
/*
* Penmount serial touchscreen driver
*
* Copyright (c) 2006 Rick Koch <n1gp@hotmail.com>
* Copyright (c) 2011 John Sung <penmount.touch@gmail.com>
*
* Based on ELO driver (drivers/input/touchscreen/elo.c)
* 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.
*/
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/serio.h>
#include <linux/init.h>
#define DRIVER_DESC "PenMount serial touchscreen driver"
MODULE_AUTHOR("Rick Koch <n1gp@hotmail.com>");
MODULE_AUTHOR("John Sung <penmount.touch@gmail.com>");
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
/*
* Definitions & global arrays.
*/
#define PM_MAX_LENGTH 6
#define PM_MAX_MTSLOT 16
#define PM_3000_MTSLOT 2
#define PM_6250_MTSLOT 12
/*
* Multi-touch slot
*/
struct mt_slot {
unsigned short x, y;
bool active; /* is the touch valid? */
};
/*
* Per-touchscreen data.
*/
struct pm {
struct input_dev *dev;
struct serio *serio;
int idx;
unsigned char data[PM_MAX_LENGTH];
char phys[32];
unsigned char packetsize;
unsigned char maxcontacts;
struct mt_slot slots[PM_MAX_MTSLOT];
void (*parse_packet)(struct pm *);
};
/*
* pm_mtevent() sends mt events and also emulates pointer movement
*/
static void pm_mtevent(struct pm *pm, struct input_dev *input)
{
int i;
for (i = 0; i < pm->maxcontacts; ++i) {
input_mt_slot(input, i);
input_mt_report_slot_state(input, MT_TOOL_FINGER,
pm->slots[i].active);
if (pm->slots[i].active) {
input_event(input, EV_ABS, ABS_MT_POSITION_X, pm->slots[i].x);
input_event(input, EV_ABS, ABS_MT_POSITION_Y, pm->slots[i].y);
}
}
input_mt_report_pointer_emulation(input, true);
input_sync(input);
}
/*
* pm_checkpacket() checks if data packet is valid
*/
static bool pm_checkpacket(unsigned char *packet)
{
int total = 0;
int i;
for (i = 0; i < 5; i++)
total += packet[i];
return packet[5] == (unsigned char)~(total & 0xff);
}
static void pm_parse_9000(struct pm *pm)
{
struct input_dev *dev = pm->dev;
if ((pm->data[0] & 0x80) && pm->packetsize == ++pm->idx) {
input_report_abs(dev, ABS_X, pm->data[1] * 128 + pm->data[2]);
input_report_abs(dev, ABS_Y, pm->data[3] * 128 + pm->data[4]);
input_report_key(dev, BTN_TOUCH, !!(pm->data[0] & 0x40));
input_sync(dev);
pm->idx = 0;
}
}
static void pm_parse_6000(struct pm *pm)
{
struct input_dev *dev = pm->dev;
if ((pm->data[0] & 0xbf) == 0x30 && pm->packetsize == ++pm->idx) {
if (pm_checkpacket(pm->data)) {
input_report_abs(dev, ABS_X,
pm->data[2] * 256 + pm->data[1]);
input_report_abs(dev, ABS_Y,
pm->data[4] * 256 + pm->data[3]);
input_report_key(dev, BTN_TOUCH, pm->data[0] & 0x40);
input_sync(dev);
}
pm->idx = 0;
}
}
static void pm_parse_3000(struct pm *pm)
{
struct input_dev *dev = pm->dev;
if ((pm->data[0] & 0xce) == 0x40 && pm->packetsize == ++pm->idx) {
if (pm_checkpacket(pm->data)) {
int slotnum = pm->data[0] & 0x0f;
pm->slots[slotnum].active = pm->data[0] & 0x30;
pm->slots[slotnum].x = pm->data[2] * 256 + pm->data[1];
pm->slots[slotnum].y = pm->data[4] * 256 + pm->data[3];
pm_mtevent(pm, dev);
}
pm->idx = 0;
}
}
static void pm_parse_6250(struct pm *pm)
{
struct input_dev *dev = pm->dev;
if ((pm->data[0] & 0xb0) == 0x30 && pm->packetsize == ++pm->idx) {
if (pm_checkpacket(pm->data)) {
int slotnum = pm->data[0] & 0x0f;
pm->slots[slotnum].active = pm->data[0] & 0x40;
pm->slots[slotnum].x = pm->data[2] * 256 + pm->data[1];
pm->slots[slotnum].y = pm->data[4] * 256 + pm->data[3];
pm_mtevent(pm, dev);
}
pm->idx = 0;
}
}
static irqreturn_t pm_interrupt(struct serio *serio,
unsigned char data, unsigned int flags)
{
struct pm *pm = serio_get_drvdata(serio);
pm->data[pm->idx] = data;
pm->parse_packet(pm);
return IRQ_HANDLED;
}
/*
* pm_disconnect() is the opposite of pm_connect()
*/
static void pm_disconnect(struct serio *serio)
{
struct pm *pm = serio_get_drvdata(serio);
serio_close(serio);
input_unregister_device(pm->dev);
kfree(pm);
serio_set_drvdata(serio, NULL);
}
/*
* pm_connect() is the routine that is called when someone adds a
* new serio device that supports PenMount protocol and registers it as
* an input device.
*/
static int pm_connect(struct serio *serio, struct serio_driver *drv)
{
struct pm *pm;
struct input_dev *input_dev;
int max_x, max_y;
int err;
pm = kzalloc(sizeof(struct pm), GFP_KERNEL);
input_dev = input_allocate_device();
if (!pm || !input_dev) {
err = -ENOMEM;
goto fail1;
}
pm->serio = serio;
pm->dev = input_dev;
snprintf(pm->phys, sizeof(pm->phys), "%s/input0", serio->phys);
pm->maxcontacts = 1;
input_dev->name = "PenMount Serial TouchScreen";
input_dev->phys = pm->phys;
input_dev->id.bustype = BUS_RS232;
input_dev->id.vendor = SERIO_PENMOUNT;
input_dev->id.product = 0;
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);
switch (serio->id.id) {
default:
case 0:
pm->packetsize = 5;
pm->parse_packet = pm_parse_9000;
input_dev->id.product = 0x9000;
max_x = max_y = 0x3ff;
break;
case 1:
pm->packetsize = 6;
pm->parse_packet = pm_parse_6000;
input_dev->id.product = 0x6000;
max_x = max_y = 0x3ff;
break;
case 2:
pm->packetsize = 6;
pm->parse_packet = pm_parse_3000;
input_dev->id.product = 0x3000;
max_x = max_y = 0x7ff;
pm->maxcontacts = PM_3000_MTSLOT;
break;
case 3:
pm->packetsize = 6;
pm->parse_packet = pm_parse_6250;
input_dev->id.product = 0x6250;
max_x = max_y = 0x3ff;
pm->maxcontacts = PM_6250_MTSLOT;
break;
}
input_set_abs_params(pm->dev, ABS_X, 0, max_x, 0, 0);
input_set_abs_params(pm->dev, ABS_Y, 0, max_y, 0, 0);
if (pm->maxcontacts > 1) {
input_mt_init_slots(pm->dev, pm->maxcontacts, 0);
input_set_abs_params(pm->dev,
ABS_MT_POSITION_X, 0, max_x, 0, 0);
input_set_abs_params(pm->dev,
ABS_MT_POSITION_Y, 0, max_y, 0, 0);
}
serio_set_drvdata(serio, pm);
err = serio_open(serio, drv);
if (err)
goto fail2;
err = input_register_device(pm->dev);
if (err)
goto fail3;
return 0;
fail3: serio_close(serio);
fail2: serio_set_drvdata(serio, NULL);
fail1: input_free_device(input_dev);
kfree(pm);
return err;
}
/*
* The serio driver structure.
*/
static struct serio_device_id pm_serio_ids[] = {
{
.type = SERIO_RS232,
.proto = SERIO_PENMOUNT,
.id = SERIO_ANY,
.extra = SERIO_ANY,
},
{ 0 }
};
MODULE_DEVICE_TABLE(serio, pm_serio_ids);
static struct serio_driver pm_drv = {
.driver = {
.name = "serio-penmount",
},
.description = DRIVER_DESC,
.id_table = pm_serio_ids,
.interrupt = pm_interrupt,
.connect = pm_connect,
.disconnect = pm_disconnect,
};
module_serio_driver(pm_drv);