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linux/drivers/input/touchscreen/wacom_w8001.c
Ping Cheng 28a1bc1c0a Input: wacom_w8001 - report resolution to userland
Serial devices send both pen and touch data through the same logical
port. Since we scaled touch to pen maximum, we use pen resolution
for touch as well here.

This is under the assumption that pen and touch share the same physical
surface. In the case when a small physical dimensional difference occurs
between pen and touch, we assume the tolerance for touch point precision
is higher than pen and the difference is within touch point tolerance.

A per-MT tool based resolution mechanism should be introduced if the
above assumption does not hold true for the pen and touch devices any
more.

Signed-off-by: Ping Cheng <pingc@wacom.com>
Reviewed-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2011-01-31 21:32:24 -08:00

588 lines
14 KiB
C

/*
* Wacom W8001 penabled serial touchscreen driver
*
* Copyright (c) 2008 Jaya Kumar
* Copyright (c) 2010 Red Hat, Inc.
* Copyright (c) 2010 - 2011 Ping Cheng, Wacom. <pingc@wacom.com>
*
* 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/mt.h>
#include <linux/serio.h>
#include <linux/init.h>
#include <linux/ctype.h>
#include <linux/delay.h>
#define DRIVER_DESC "Wacom W8001 serial touchscreen driver"
MODULE_AUTHOR("Jaya Kumar <jayakumar.lkml@gmail.com>");
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
#define W8001_MAX_LENGTH 11
#define W8001_LEAD_MASK 0x80
#define W8001_LEAD_BYTE 0x80
#define W8001_TAB_MASK 0x40
#define W8001_TAB_BYTE 0x40
/* set in first byte of touch data packets */
#define W8001_TOUCH_MASK (0x10 | W8001_LEAD_MASK)
#define W8001_TOUCH_BYTE (0x10 | W8001_LEAD_BYTE)
#define W8001_QUERY_PACKET 0x20
#define W8001_CMD_STOP '0'
#define W8001_CMD_START '1'
#define W8001_CMD_QUERY '*'
#define W8001_CMD_TOUCHQUERY '%'
/* length of data packets in bytes, depends on device. */
#define W8001_PKTLEN_TOUCH93 5
#define W8001_PKTLEN_TOUCH9A 7
#define W8001_PKTLEN_TPCPEN 9
#define W8001_PKTLEN_TPCCTL 11 /* control packet */
#define W8001_PKTLEN_TOUCH2FG 13
/* resolution in points/mm */
#define W8001_PEN_RESOLUTION 100
#define W8001_TOUCH_RESOLUTION 10
struct w8001_coord {
u8 rdy;
u8 tsw;
u8 f1;
u8 f2;
u16 x;
u16 y;
u16 pen_pressure;
u8 tilt_x;
u8 tilt_y;
};
/* touch query reply packet */
struct w8001_touch_query {
u16 x;
u16 y;
u8 panel_res;
u8 capacity_res;
u8 sensor_id;
};
/*
* Per-touchscreen data.
*/
struct w8001 {
struct input_dev *dev;
struct serio *serio;
struct completion cmd_done;
int id;
int idx;
unsigned char response_type;
unsigned char response[W8001_MAX_LENGTH];
unsigned char data[W8001_MAX_LENGTH];
char phys[32];
int type;
unsigned int pktlen;
u16 max_touch_x;
u16 max_touch_y;
u16 max_pen_x;
u16 max_pen_y;
char name[64];
};
static void parse_pen_data(u8 *data, struct w8001_coord *coord)
{
memset(coord, 0, sizeof(*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;
}
static void parse_single_touch(u8 *data, struct w8001_coord *coord)
{
coord->x = (data[1] << 7) | data[2];
coord->y = (data[3] << 7) | data[4];
coord->tsw = data[0] & 0x01;
}
static void scale_touch_coordinates(struct w8001 *w8001,
unsigned int *x, unsigned int *y)
{
if (w8001->max_pen_x && w8001->max_touch_x)
*x = *x * w8001->max_pen_x / w8001->max_touch_x;
if (w8001->max_pen_y && w8001->max_touch_y)
*y = *y * w8001->max_pen_y / w8001->max_touch_y;
}
static void parse_multi_touch(struct w8001 *w8001)
{
struct input_dev *dev = w8001->dev;
unsigned char *data = w8001->data;
unsigned int x, y;
int i;
int count = 0;
for (i = 0; i < 2; i++) {
bool touch = data[0] & (1 << i);
input_mt_slot(dev, i);
input_mt_report_slot_state(dev, MT_TOOL_FINGER, touch);
if (touch) {
x = (data[6 * i + 1] << 7) | data[6 * i + 2];
y = (data[6 * i + 3] << 7) | data[6 * i + 4];
/* data[5,6] and [11,12] is finger capacity */
/* scale to pen maximum */
scale_touch_coordinates(w8001, &x, &y);
input_report_abs(dev, ABS_MT_POSITION_X, x);
input_report_abs(dev, ABS_MT_POSITION_Y, y);
count++;
}
}
/* emulate single touch events when stylus is out of proximity.
* This is to make single touch backward support consistent
* across all Wacom single touch devices.
*/
if (w8001->type != BTN_TOOL_PEN &&
w8001->type != BTN_TOOL_RUBBER) {
w8001->type = count == 1 ? BTN_TOOL_FINGER : KEY_RESERVED;
input_mt_report_pointer_emulation(dev, true);
}
input_sync(dev);
}
static void parse_touchquery(u8 *data, struct w8001_touch_query *query)
{
memset(query, 0, sizeof(*query));
query->panel_res = data[1];
query->sensor_id = data[2] & 0x7;
query->capacity_res = data[7];
query->x = data[3] << 9;
query->x |= data[4] << 2;
query->x |= (data[2] >> 5) & 0x3;
query->y = data[5] << 9;
query->y |= data[6] << 2;
query->y |= (data[2] >> 3) & 0x3;
/* Early days' single-finger touch models need the following defaults */
if (!query->x && !query->y) {
query->x = 1024;
query->y = 1024;
if (query->panel_res)
query->x = query->y = (1 << query->panel_res);
query->panel_res = W8001_TOUCH_RESOLUTION;
}
}
static void report_pen_events(struct w8001 *w8001, struct w8001_coord *coord)
{
struct input_dev *dev = w8001->dev;
/*
* We have 1 bit for proximity (rdy) and 3 bits for tip, side,
* side2/eraser. If rdy && f2 are set, this can be either pen + side2,
* or eraser. Assume:
* - if dev is already in proximity and f2 is toggled → pen + side2
* - if dev comes into proximity with f2 set → eraser
* If f2 disappears after assuming eraser, fake proximity out for
* eraser and in for pen.
*/
switch (w8001->type) {
case BTN_TOOL_RUBBER:
if (!coord->f2) {
input_report_abs(dev, ABS_PRESSURE, 0);
input_report_key(dev, BTN_TOUCH, 0);
input_report_key(dev, BTN_STYLUS, 0);
input_report_key(dev, BTN_STYLUS2, 0);
input_report_key(dev, BTN_TOOL_RUBBER, 0);
input_sync(dev);
w8001->type = BTN_TOOL_PEN;
}
break;
case BTN_TOOL_FINGER:
input_report_key(dev, BTN_TOUCH, 0);
input_report_key(dev, BTN_TOOL_FINGER, 0);
input_sync(dev);
/* fall through */
case KEY_RESERVED:
w8001->type = coord->f2 ? BTN_TOOL_RUBBER : BTN_TOOL_PEN;
break;
default:
input_report_key(dev, BTN_STYLUS2, coord->f2);
break;
}
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_report_key(dev, BTN_STYLUS, coord->f1);
input_report_key(dev, w8001->type, coord->rdy);
input_sync(dev);
if (!coord->rdy)
w8001->type = KEY_RESERVED;
}
static void report_single_touch(struct w8001 *w8001, struct w8001_coord *coord)
{
struct input_dev *dev = w8001->dev;
unsigned int x = coord->x;
unsigned int y = coord->y;
/* scale to pen maximum */
scale_touch_coordinates(w8001, &x, &y);
input_report_abs(dev, ABS_X, x);
input_report_abs(dev, ABS_Y, y);
input_report_key(dev, BTN_TOUCH, coord->tsw);
input_report_key(dev, BTN_TOOL_FINGER, coord->tsw);
input_sync(dev);
w8001->type = coord->tsw ? BTN_TOOL_FINGER : KEY_RESERVED;
}
static irqreturn_t w8001_interrupt(struct serio *serio,
unsigned char data, unsigned int flags)
{
struct w8001 *w8001 = serio_get_drvdata(serio);
struct w8001_coord coord;
unsigned char tmp;
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 W8001_PKTLEN_TOUCH93 - 1:
case W8001_PKTLEN_TOUCH9A - 1:
tmp = w8001->data[0] & W8001_TOUCH_BYTE;
if (tmp != W8001_TOUCH_BYTE)
break;
if (w8001->pktlen == w8001->idx) {
w8001->idx = 0;
if (w8001->type != BTN_TOOL_PEN &&
w8001->type != BTN_TOOL_RUBBER) {
parse_single_touch(w8001->data, &coord);
report_single_touch(w8001, &coord);
}
}
break;
/* Pen coordinates packet */
case W8001_PKTLEN_TPCPEN - 1:
tmp = w8001->data[0] & W8001_TAB_MASK;
if (unlikely(tmp == W8001_TAB_BYTE))
break;
tmp = w8001->data[0] & W8001_TOUCH_BYTE;
if (tmp == W8001_TOUCH_BYTE)
break;
w8001->idx = 0;
parse_pen_data(w8001->data, &coord);
report_pen_events(w8001, &coord);
break;
/* control packet */
case W8001_PKTLEN_TPCCTL - 1:
tmp = w8001->data[0] & W8001_TOUCH_MASK;
if (tmp == W8001_TOUCH_BYTE)
break;
w8001->idx = 0;
memcpy(w8001->response, w8001->data, W8001_MAX_LENGTH);
w8001->response_type = W8001_QUERY_PACKET;
complete(&w8001->cmd_done);
break;
/* 2 finger touch packet */
case W8001_PKTLEN_TOUCH2FG - 1:
w8001->idx = 0;
parse_multi_touch(w8001);
break;
}
return IRQ_HANDLED;
}
static int w8001_command(struct w8001 *w8001, unsigned char command,
bool wait_response)
{
int rc;
w8001->response_type = 0;
init_completion(&w8001->cmd_done);
rc = serio_write(w8001->serio, command);
if (rc == 0 && wait_response) {
wait_for_completion_timeout(&w8001->cmd_done, HZ);
if (w8001->response_type != W8001_QUERY_PACKET)
rc = -EIO;
}
return rc;
}
static int w8001_setup(struct w8001 *w8001)
{
struct input_dev *dev = w8001->dev;
struct w8001_coord coord;
struct w8001_touch_query touch;
int error;
error = w8001_command(w8001, W8001_CMD_STOP, false);
if (error)
return error;
msleep(250); /* wait 250ms before querying the device */
dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
strlcat(w8001->name, "Wacom Serial", sizeof(w8001->name));
/* penabled? */
error = w8001_command(w8001, W8001_CMD_QUERY, true);
if (!error) {
__set_bit(BTN_TOUCH, dev->keybit);
__set_bit(BTN_TOOL_PEN, dev->keybit);
__set_bit(BTN_TOOL_RUBBER, dev->keybit);
__set_bit(BTN_STYLUS, dev->keybit);
__set_bit(BTN_STYLUS2, dev->keybit);
parse_pen_data(w8001->response, &coord);
w8001->max_pen_x = coord.x;
w8001->max_pen_y = coord.y;
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_abs_set_res(dev, ABS_X, W8001_PEN_RESOLUTION);
input_abs_set_res(dev, ABS_Y, W8001_PEN_RESOLUTION);
input_set_abs_params(dev, ABS_PRESSURE, 0, coord.pen_pressure, 0, 0);
if (coord.tilt_x && coord.tilt_y) {
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);
}
w8001->id = 0x90;
strlcat(w8001->name, " Penabled", sizeof(w8001->name));
}
/* Touch enabled? */
error = w8001_command(w8001, W8001_CMD_TOUCHQUERY, true);
/*
* Some non-touch devices may reply to the touch query. But their
* second byte is empty, which indicates touch is not supported.
*/
if (!error && w8001->response[1]) {
__set_bit(BTN_TOUCH, dev->keybit);
__set_bit(BTN_TOOL_FINGER, dev->keybit);
parse_touchquery(w8001->response, &touch);
w8001->max_touch_x = touch.x;
w8001->max_touch_y = touch.y;
if (w8001->max_pen_x && w8001->max_pen_y) {
/* if pen is supported scale to pen maximum */
touch.x = w8001->max_pen_x;
touch.y = w8001->max_pen_y;
touch.panel_res = W8001_PEN_RESOLUTION;
}
input_set_abs_params(dev, ABS_X, 0, touch.x, 0, 0);
input_set_abs_params(dev, ABS_Y, 0, touch.y, 0, 0);
input_abs_set_res(dev, ABS_X, touch.panel_res);
input_abs_set_res(dev, ABS_Y, touch.panel_res);
switch (touch.sensor_id) {
case 0:
case 2:
w8001->pktlen = W8001_PKTLEN_TOUCH93;
w8001->id = 0x93;
strlcat(w8001->name, " 1FG", sizeof(w8001->name));
break;
case 1:
case 3:
case 4:
w8001->pktlen = W8001_PKTLEN_TOUCH9A;
strlcat(w8001->name, " 1FG", sizeof(w8001->name));
w8001->id = 0x9a;
break;
case 5:
w8001->pktlen = W8001_PKTLEN_TOUCH2FG;
input_mt_init_slots(dev, 2);
input_set_abs_params(dev, ABS_MT_POSITION_X,
0, touch.x, 0, 0);
input_set_abs_params(dev, ABS_MT_POSITION_Y,
0, touch.y, 0, 0);
input_set_abs_params(dev, ABS_MT_TOOL_TYPE,
0, MT_TOOL_MAX, 0, 0);
strlcat(w8001->name, " 2FG", sizeof(w8001->name));
if (w8001->max_pen_x && w8001->max_pen_y)
w8001->id = 0xE3;
else
w8001->id = 0xE2;
break;
}
}
strlcat(w8001->name, " Touchscreen", sizeof(w8001->name));
return w8001_command(w8001, W8001_CMD_START, false);
}
/*
* 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->dev = input_dev;
init_completion(&w8001->cmd_done);
snprintf(w8001->phys, sizeof(w8001->phys), "%s/input0", serio->phys);
serio_set_drvdata(serio, w8001);
err = serio_open(serio, drv);
if (err)
goto fail2;
err = w8001_setup(w8001);
if (err)
goto fail3;
input_dev->name = w8001->name;
input_dev->phys = w8001->phys;
input_dev->id.product = w8001->id;
input_dev->id.bustype = BUS_RS232;
input_dev->id.vendor = 0x056a;
input_dev->id.version = 0x0100;
input_dev->dev.parent = &serio->dev;
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);