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Release 4.11 drivers/input/touchscreen/wacom_w8001.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/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	13

#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 *pen_dev;
	
struct input_dev *touch_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 pen_name[64];
	
char touch_name[64];
	
int open_count;
	
struct mutex mutex;
};


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; }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar19592.86%133.33%
Dmitry Torokhov146.67%133.33%
Ping Cheng10.48%133.33%
Total210100.00%3100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Ping Cheng62100.00%1100.00%
Total62100.00%1100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Ping Cheng69100.00%1100.00%
Total69100.00%1100.00%


static void parse_multi_touch(struct w8001 *w8001) { struct input_dev *dev = w8001->touch_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); }

Contributors

PersonTokensPropCommitsCommitProp
Peter Hutterer12758.53%240.00%
Ping Cheng6730.88%120.00%
Henrik Rydberg146.45%120.00%
Dmitry Torokhov94.15%120.00%
Total217100.00%5100.00%


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; } }

Contributors

PersonTokensPropCommitsCommitProp
Peter Hutterer14276.34%250.00%
Ping Cheng4423.66%250.00%
Total186100.00%4100.00%


static void report_pen_events(struct w8001 *w8001, struct w8001_coord *coord) { struct input_dev *dev = w8001->pen_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: 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; }

Contributors

PersonTokensPropCommitsCommitProp
Peter Hutterer16775.57%266.67%
Ping Cheng5424.43%133.33%
Total221100.00%3100.00%


static void report_single_touch(struct w8001 *w8001, struct w8001_coord *coord) { struct input_dev *dev = w8001->touch_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_sync(dev); w8001->type = coord->tsw ? BTN_TOOL_FINGER : KEY_RESERVED; }

Contributors

PersonTokensPropCommitsCommitProp
Ping Cheng9696.97%133.33%
Peter Hutterer33.03%266.67%
Total99100.00%3100.00%


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; default: /* * ThinkPad X60 Tablet PC (pen only device) sometimes * sends invalid data packets that are larger than * W8001_PKTLEN_TPCPEN. Let's start over again. */ if (!w8001->touch_dev && w8001->idx > W8001_PKTLEN_TPCPEN - 1) w8001->idx = 0; } return IRQ_HANDLED; }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar14542.77%114.29%
Peter Hutterer9126.84%342.86%
Ping Cheng7923.30%228.57%
Dmitry Torokhov247.08%114.29%
Total339100.00%7100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar6174.39%150.00%
Dmitry Torokhov2125.61%150.00%
Total82100.00%2100.00%


static int w8001_open(struct input_dev *dev) { struct w8001 *w8001 = input_get_drvdata(dev); int err; err = mutex_lock_interruptible(&w8001->mutex); if (err) return err; if (w8001->open_count++ == 0) { err = w8001_command(w8001, W8001_CMD_START, false); if (err) w8001->open_count--; } mutex_unlock(&w8001->mutex); return err; }

Contributors

PersonTokensPropCommitsCommitProp
Peter Hutterer5262.65%150.00%
Dmitry Torokhov3137.35%150.00%
Total83100.00%2100.00%


static void w8001_close(struct input_dev *dev) { struct w8001 *w8001 = input_get_drvdata(dev); mutex_lock(&w8001->mutex); if (--w8001->open_count == 0) w8001_command(w8001, W8001_CMD_STOP, false); mutex_unlock(&w8001->mutex); }

Contributors

PersonTokensPropCommitsCommitProp
Dmitry Torokhov3054.55%150.00%
Peter Hutterer2545.45%150.00%
Total55100.00%2100.00%


static int w8001_detect(struct w8001 *w8001) { int error; error = w8001_command(w8001, W8001_CMD_STOP, false); if (error) return error; msleep(250); /* wait 250ms before querying the device */ return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar1946.34%125.00%
Dmitry Torokhov921.95%125.00%
Ping Cheng819.51%125.00%
Peter Hutterer512.20%125.00%
Total41100.00%4100.00%


static int w8001_setup_pen(struct w8001 *w8001, char *basename, size_t basename_sz) { struct input_dev *dev = w8001->pen_dev; struct w8001_coord coord; int error; /* penabled? */ error = w8001_command(w8001, W8001_CMD_QUERY, true); if (error) return error; __set_bit(EV_KEY, dev->evbit); __set_bit(EV_ABS, dev->evbit); __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); __set_bit(INPUT_PROP_DIRECT, dev->propbit); 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(basename, " Penabled", basename_sz); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Ping Cheng12042.25%342.86%
Jaya Kumar9132.04%114.29%
Peter Hutterer7024.65%228.57%
Dmitry Torokhov31.06%114.29%
Total284100.00%7100.00%


static int w8001_setup_touch(struct w8001 *w8001, char *basename, size_t basename_sz) { struct input_dev *dev = w8001->touch_dev; struct w8001_touch_query touch; int error; /* Touch enabled? */ error = w8001_command(w8001, W8001_CMD_TOUCHQUERY, true); if (error) return error; /* * Some non-touch devices may reply to the touch query. But their * second byte is empty, which indicates touch is not supported. */ if (!w8001->response[1]) return -ENXIO; __set_bit(EV_KEY, dev->evbit); __set_bit(EV_ABS, dev->evbit); __set_bit(BTN_TOUCH, dev->keybit); __set_bit(INPUT_PROP_DIRECT, dev->propbit); 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(basename, " 1FG", basename_sz); break; case 1: case 3: case 4: w8001->pktlen = W8001_PKTLEN_TOUCH9A; strlcat(basename, " 1FG", basename_sz); w8001->id = 0x9a; break; case 5: w8001->pktlen = W8001_PKTLEN_TOUCH2FG; __set_bit(BTN_TOOL_DOUBLETAP, dev->keybit); error = input_mt_init_slots(dev, 2, 0); if (error) { dev_err(&w8001->serio->dev, "failed to initialize MT slots: %d\n", error); return error; } 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); input_abs_set_res(dev, ABS_MT_POSITION_X, touch.panel_res); input_abs_set_res(dev, ABS_MT_POSITION_Y, touch.panel_res); strlcat(basename, " 2FG", basename_sz); if (w8001->max_pen_x && w8001->max_pen_y) w8001->id = 0xE3; else w8001->id = 0xE2; break; } strlcat(basename, " Touchscreen", basename_sz); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Ping Cheng24453.51%529.41%
Peter Hutterer19041.67%635.29%
Dmitry Torokhov173.73%317.65%
Henrik Rydberg30.66%211.76%
Jaya Kumar20.44%15.88%
Total456100.00%17100.00%


static void w8001_set_devdata(struct input_dev *dev, struct w8001 *w8001, struct serio *serio) { dev->phys = w8001->phys; dev->id.bustype = BUS_RS232; dev->id.product = w8001->id; dev->id.vendor = 0x056a; dev->id.version = 0x0100; dev->open = w8001_open; dev->close = w8001_close; dev->dev.parent = &serio->dev; input_set_drvdata(dev, w8001); }

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PersonTokensPropCommitsCommitProp
Peter Hutterer93100.00%1100.00%
Total93100.00%1100.00%

/* * w8001_disconnect() is the opposite of w8001_connect() */
static void w8001_disconnect(struct serio *serio) { struct w8001 *w8001 = serio_get_drvdata(serio); serio_close(serio); if (w8001->pen_dev) input_unregister_device(w8001->pen_dev); if (w8001->touch_dev) input_unregister_device(w8001->touch_dev); kfree(w8001); serio_set_drvdata(serio, NULL); }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar4062.50%133.33%
Peter Hutterer2031.25%133.33%
Dmitry Torokhov46.25%133.33%
Total64100.00%3100.00%

/* * 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_pen; struct input_dev *input_dev_touch; char basename[64]; int err, err_pen, err_touch; w8001 = kzalloc(sizeof(struct w8001), GFP_KERNEL); input_dev_pen = input_allocate_device(); input_dev_touch = input_allocate_device(); if (!w8001 || !input_dev_pen || !input_dev_touch) { err = -ENOMEM; goto fail1;