android系统开发(四)-触摸屏tslib移植(内核)和原理分析

首先了解一下tslib的运行原理，tslib的运行分成两部分
(1)校验
在LCD固定坐标位置依次显示出5个坐标让用户触摸，把LCD坐标和用户触摸时驱动屏驱动底层的坐标总共5组值保存起来
运行tslib库的算法对其进行运算，得出校准用7个值

(2)校准
每次触摸屏驱动读取到硬件坐标时应用校准用的7个值对该坐标进行一次运算，然后将运算后的坐标作为正常坐标即可。

按照上面的原理，
(1)我们先修改内核部分，我的平台用的触摸屏幕驱动是tsc2007，驱动文件为内核/drivers/input/touchscreen
目录下的tsc2007.c和ts_linear.c
其中，ts_linear.c中定义的是校准模块，该模块在proc文件系统中建立了7个文件，用来存放校准用的7个点，7的点的默认值
为1,0,0,0,1,0,1，对应的目标平台文件系统的位置为/proc/sys/dev/ts_device目录下a0,a1,a2,a3,a4,a5,a6等7个文件
此模块中还定义了一个校准函数ts_linear_scale，此函数的主要内容是读取a0,a1,a2,a3,a4,a5,a6等7个文件中的值作为7个
校准值与传入的触摸平坐标值进行运算，返回运算结果。
ts_linear_scale函数定义如下：
int ts_linear_scale(int *x, int *y, int swap_xy)
{
    int xtemp, ytemp;

    xtemp = *x;
    ytemp = *y;

    if (cal.a[6] == 0)
        return -EINVAL;

    *x = (cal.a[2] + cal.a[0] * xtemp + cal.a[1] * ytemp) / cal.a[6];
    *y = (cal.a[5] + cal.a[3] * xtemp + cal.a[4] * ytemp) / cal.a[6];

    if (swap_xy) {
        int tmp = *x;
        *x = *y;
        *y = tmp;
    }
    return 0;
}

ts2007.c为触摸屏驱，与其他驱动不同的地方是在取得硬件坐标值发送之前先调用了ts_linear_scale函数对坐标值进行了校准
            if (x > 0 && y > 0)
            {
                ts_linear_scale(&x, &y, invert);
                input_report_abs(input, ABS_X, x);
                input_report_abs(input, ABS_Y, y);
                input_report_abs(input, ABS_PRESSURE, 255);
                input_report_abs(input, ABS_TOOL_WIDTH, 1);
                input_report_key(input, BTN_TOUCH, 1);
                input_sync(input);
            }

(2)在android源代码/system/core/rootdir/init.rc文件中添加tslib相关的宏定义如下：
# touchscreen parameters
    export TSLIB_FBDEVICE /dev/graphics/fb0
    export TSLIB_CALIBFILE /data/etc/pointercal
    export TSLIB_CONFFILE  /system/etc/ts.conf
    export TSLIB_TRIGGERDEV /dev/input/event0
    export TSLIB_TSDEVICE /dev/input/event1

(2)移植tslib库到android系统，比较麻烦，看下一节的内容。

(3)校验程序完成后会将生成的7个校准值写入到环境变量TSLIB_CALIBFILE对应的路径/data/etc/pointercal文件中

(4)校验完后将pointercal文件中的7个值分别写入到/proc/sys/dev/ts_device目录下a0,a1,a2,a3,a4,a5,a6文件即可。

(5)开机启动的时候我们编写一个应用程序，首先判断环境变量TSLIB_CALIBFILE对应的路径/data/etc/pointercal文件是否存在，如果
文件存在而且非空，则将该文件中的7个值取出来分别写入到/proc/sys/dev/ts_device目录下a0,a1,a2,a3,a4,a5,a6文件

(6)为了确保未校验前触摸屏可用，我们将一次校验后得出的7个坐标值作为初始值，修改到内核ts_linear.c文件中。

 

下面是源代码：
ts_linear.c文件
/*
 *  Touchscreen Linear Scale Adaptor
 *
 *  Copyright (C) 2009 Marvell Corporation
 * 
 *  Author: Mark F. Brown <[e-mail]>
 *  Based on tslib 1.0 plugin linear.c by Russel King
 *
 * This library is licensed under GPL.
 *
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/wait.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/proc_fs.h>
#include <linux/sysctl.h>
#include <asm/system.h>

/*
 * sysctl-tuning infrastructure.
 */
static struct ts_calibration {
/* Linear scaling and offset parameters for x,y (can include rotation) */
    int a[7];
} cal;

static ctl_table ts_proc_calibration_table[] = {
    {
     .ctl_name = CTL_UNNUMBERED,
     .procname = "a0",
     .data = &cal.a[0],
     .maxlen = sizeof(int),
     .mode = 0666,
     .proc_handler = &proc_dointvec,
     },
    {
     .ctl_name = CTL_UNNUMBERED,
     .procname = "a1",
     .data = &cal.a[1],
     .maxlen = sizeof(int),
     .mode = 0666,
     .proc_handler = &proc_dointvec,
     },
    {
     .ctl_name = CTL_UNNUMBERED,
     .procname = "a2",
     .data = &cal.a[2],
     .maxlen = sizeof(int),
     .mode = 0666,
     .proc_handler = &proc_dointvec,
     },
    {
     .ctl_name = CTL_UNNUMBERED,
     .procname = "a3",
     .data = &cal.a[3],
     .maxlen = sizeof(int),
     .mode = 0666,
     .proc_handler = &proc_dointvec,
     },
    {
     .ctl_name = CTL_UNNUMBERED,
     .procname = "a4",
     .data = &cal.a[4],
     .maxlen = sizeof(int),
     .mode = 0666,
     .proc_handler = &proc_dointvec,
     },
    {
     .ctl_name = CTL_UNNUMBERED,
     .procname = "a5",
     .data = &cal.a[5],
     .maxlen = sizeof(int),
     .mode = 0666,
     .proc_handler = &proc_dointvec,
     },
    {
     .ctl_name = CTL_UNNUMBERED,
     .procname = "a6",
     .data = &cal.a[6],
     .maxlen = sizeof(int),
     .mode = 0666,
     .proc_handler = &proc_dointvec,
     },

    {.ctl_name = 0}
};

static ctl_table ts_proc_root[] = {
    {
     .ctl_name = CTL_UNNUMBERED,
     .procname = "ts_device",
     .mode = 0555,
     .child = ts_proc_calibration_table,
     },
    {.ctl_name = 0}
};

static ctl_table ts_dev_root[] = {
    {
     .ctl_name = CTL_DEV,
     .procname = "dev",
     .mode = 0555,
     .child = ts_proc_root,
     },
    {.ctl_name = 0}
};

static struct ctl_table_header *ts_sysctl_header;

int ts_linear_scale(int *x, int *y, int swap_xy)
{
    int xtemp, ytemp;

    xtemp = *x;
    ytemp = *y;

    if (cal.a[6] == 0)
        return -EINVAL;

    *x = (cal.a[2] + cal.a[0] * xtemp + cal.a[1] * ytemp) / cal.a[6];
    *y = (cal.a[5] + cal.a[3] * xtemp + cal.a[4] * ytemp) / cal.a[6];

    if (swap_xy) {
        int tmp = *x;
        *x = *y;
        *y = tmp;
    }
    return 0;
}

EXPORT_SYMBOL(ts_linear_scale);

static int __init ts_linear_init(void)
{
    ts_sysctl_header = register_sysctl_table(ts_dev_root);
    /* Use default values that leave ts numbers unchanged after transform */
    cal.a[0] = 1;
    cal.a[1] = 0;
    cal.a[2] = 0;
    cal.a[3] = 0;
    cal.a[4] = 1;
    cal.a[5] = 0;
    cal.a[6] = 1;
    return 0;
}

static void __exit ts_linear_cleanup(void)
{
    unregister_sysctl_table(ts_sysctl_header);
}

module_init(ts_linear_init);
module_exit(ts_linear_cleanup);

MODULE_DESCRIPTION("touch screen linear scaling driver");
MODULE_LICENSE("GPL");



ts2007.c文件
/*
 *  linux/drivers/input/touchscreen/tsc2007.c
 *
 *  touch screen driver for tsc2007
 *
 *  Copyright (C) 2006, Marvell Corporation
 *
 *  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/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/wait.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/freezer.h>
#include <linux/proc_fs.h>
#include <linux/clk.h>
#include <linux/i2c.h>
#include <mach/gpio.h>

#include <linux/sysctl.h>
#include <asm/system.h>

extern int ts_linear_scale(int *x, int *y, int swap_xy);

/* Use MAV filter */
#define TSC_CMD_SETUP 0xb0

/* Use 12-bit */
#define TSC_CMD_X 0xc0
#define TSC_CMD_PLATEX 0x80
#define TSC_CMD_Y 0xd0
#define TSC_CMD_PLATEY 0x90

#define TSC_X_MAX 4096
#define TSC_Y_MAX 4096
#define TSC_X_MIN 0
#define TSC_Y_MIN 0

/* delay time for compute x, y, computed as us */

#define DEBUG
#ifdef DEBUG
#define TS_DEBUG(fmt,args...) printk(KERN_DEBUG fmt, ##args )
#else
#define TS_DEBUG(fmt,args...)
#endif
static int x_min=TSC_X_MIN;
static int y_min=TSC_Y_MIN;
static int x_max=TSC_X_MAX;
static int y_max=TSC_Y_MAX;
static int invert = 0;
static int debounce_time  = 150;
static int init_debounce = true;
static int delay_time = 1;

enum tsc2007_status {
    PEN_UP,
    PEN_DOWN,
};

struct _tsc2007 {
    struct input_dev *dev;
    int x;        /* X sample values */
    int y;        /* Y sample values */

    int status;
    struct work_struct irq_work;
    struct i2c_client *client;
    unsigned long last_touch;
};
struct _tsc2007 *g_tsc2007;

/* update abs params when min and max coordinate values are set */
int tsc2007_proc_minmax(struct ctl_table *table, int write, struct file *filp,
                     void __user *buffer, size_t *lenp, loff_t *ppos)
{
    struct _tsc2007 *tsc2007= g_tsc2007;
    struct input_dev *input = tsc2007->dev;

    /* update value */
    int ret = proc_dointvec(table, write, filp, buffer, lenp, ppos);

    /* updated abs params */
    if (input) {
        TS_DEBUG(KERN_DEBUG "update x_min %d x_max %d"
            " y_min %d y_max %d/n", x_min, x_max,
            y_min, y_max); 
        input_set_abs_params(input, ABS_X, x_min, x_max, 0, 0);
        input_set_abs_params(input, ABS_Y, y_min, y_max, 0, 0);
    }
    return ret;
}

static ctl_table tsc2007_proc_table[] = {
    {
        .ctl_name    = CTL_UNNUMBERED,
        .procname    = "x-max",
        .data        = &x_max,
        .maxlen        = sizeof(int),
        .mode        = 0666,
        .proc_handler    = &tsc2007_proc_minmax,
    },
    {
        .ctl_name    = CTL_UNNUMBERED,
        .procname    = "y-max",
        .data        = &y_max,
        .maxlen        = sizeof(int),
        .mode        = 0666,
        .proc_handler    = &tsc2007_proc_minmax,
    },
    {
        .ctl_name    = CTL_UNNUMBERED,
        .procname    = "x-min",
        .data        = &x_min,
        .maxlen        = sizeof(int),
        .mode        = 0666,
        .proc_handler    = &tsc2007_proc_minmax,
    },
    {
        .ctl_name    = CTL_UNNUMBERED,
        .procname    = "y-min",
        .data        = &y_min,
        .maxlen        = sizeof(int),
        .mode        = 0666,
        .proc_handler    = &tsc2007_proc_minmax,
    },
    {
        .ctl_name    = CTL_UNNUMBERED,
        .procname    = "invert_xy",
        .data        = &invert,
        .maxlen        = sizeof(int),
        .mode        = 0666,
        .proc_handler    = &proc_dointvec,
    },
    {
        .ctl_name    = CTL_UNNUMBERED,
        .procname    = "debounce_time",
        .data        = &debounce_time,
        .maxlen        = sizeof(int),
        .mode        = 0666,
        .proc_handler    = &proc_dointvec,
    },
    {
        .ctl_name    = CTL_UNNUMBERED,
        .procname    = "delay_time",
        .data        = &delay_time,
        .maxlen        = sizeof(int),
        .mode        = 0666,
        .proc_handler    = &proc_dointvec,
    },
    { .ctl_name = 0 }
};

static ctl_table tsc2007_proc_root[] = {
    {
        .ctl_name    = CTL_UNNUMBERED,
        .procname    = "ts_device",
        .mode        = 0555,
        .child        = tsc2007_proc_table,
    },
    { .ctl_name = 0 }
};

static ctl_table tsc2007_proc_dev_root[] = {
    {
        .ctl_name    = CTL_DEV,
        .procname    = "dev",
        .mode        = 0555,
        .child        = tsc2007_proc_root,
    },
    { .ctl_name = 0 }
};

static struct ctl_table_header *sysctl_header;

static int __init init_sysctl(void)
{
    sysctl_header = register_sysctl_table(tsc2007_proc_dev_root);
    return 0;
}

static void __exit cleanup_sysctl(void)
{
    unregister_sysctl_table(sysctl_header);
}

static int tsc2007_measure(struct i2c_client *client, int *x, int * y)
{
    u8 x_buf[2] = {0, 0};
    u8 y_buf[2] = {0, 0};

    i2c_smbus_write_byte(client, TSC_CMD_PLATEX);
    msleep_interruptible(delay_time);

    i2c_smbus_write_byte(client, TSC_CMD_X);
    i2c_master_recv(client, x_buf, 2);
    *x = (x_buf[0]<<4) | (x_buf[1] >>4);

    i2c_smbus_write_byte(client, TSC_CMD_PLATEY);
    msleep_interruptible(delay_time);

    i2c_smbus_write_byte(client, TSC_CMD_Y);
    i2c_master_recv(client, y_buf, 2);
    *y = (y_buf[0]<<4) | (y_buf[1] >>4);
    *y = 4096 - *y; //added by allen
    printk("/ntouchscreen x = 0x%x, y = 0x%x/n",*x,*y);
    return 0;
}

static void tsc2007_irq_work(struct work_struct *work)
{
    struct _tsc2007 *tsc2007= g_tsc2007;
    struct i2c_client *client = tsc2007-> client;
    struct input_dev *input = tsc2007->dev;

    int x = -1, y = -1, is_valid = 0;
    int tmp_x = 0, tmp_y = 0;

    int gpio = irq_to_gpio(client->irq);


    /* Ignore if PEN_DOWN */
    if(PEN_UP == tsc2007->status){

        if (gpio_request(gpio, "tsc2007 touch detect")) {
            printk(KERN_ERR "Request GPIO failed, gpio: %X/n", gpio);
            return;
        }
        gpio_direction_input(gpio);    
        
        while(0 == gpio_get_value(gpio)){

                        if ((jiffies_to_msecs(
                                ((long)jiffies - (long)tsc2007->last_touch)) <
                 debounce_time &&
                tsc2007->status == PEN_DOWN) ||
                init_debounce)
                        {
                init_debounce = false;
                                tsc2007_measure(client, &tmp_x, &tmp_y);
                                TS_DEBUG(KERN_DEBUG
                "dropping pen touch %lu %lu (%u)/n",
                                jiffies, tsc2007->last_touch,
                                jiffies_to_msecs(
                (long)jiffies - (long)tsc2007->last_touch));
                                schedule();
                continue;
                        }


            /* continue report x, y */
            if (x > 0 && y > 0)
            {
                ts_linear_scale(&x, &y, invert);
                input_report_abs(input, ABS_X, x);
                input_report_abs(input, ABS_Y, y);
                input_report_abs(input, ABS_PRESSURE, 255);
                input_report_abs(input, ABS_TOOL_WIDTH, 1);
                input_report_key(input, BTN_TOUCH, 1);
                input_sync(input);
            }

            tsc2007->status = PEN_DOWN;
            tsc2007_measure(client, &x, &y);
            TS_DEBUG(KERN_DEBUG "pen down x=%d y=%d!/n", x, y);
            is_valid = 1;
            schedule();
        }

        if (is_valid)
        {
            /*consider PEN_UP */
            tsc2007->status = PEN_UP;
            input_report_abs(input, ABS_PRESSURE, 0);
            input_report_abs(input, ABS_TOOL_WIDTH, 1);
            input_report_key(input, BTN_TOUCH, 0);
            input_sync(input);
            tsc2007->last_touch = jiffies;
            TS_DEBUG(KERN_DEBUG "pen up!/n"); 
        }

        gpio_free(gpio);    
    }
}

static irqreturn_t tsc2007_interrupt(int irq, void *dev_id)
{    
    schedule_work(&g_tsc2007->irq_work);
    
    return IRQ_HANDLED;
}

static int __devinit tsc2007_probe(struct i2c_client *client, 
                const struct i2c_device_id *id)
{
    struct _tsc2007 *tsc2007;
    struct input_dev *input_dev;
    int ret;

    tsc2007 = kzalloc(sizeof(struct _tsc2007), GFP_KERNEL);
    input_dev = input_allocate_device();

    g_tsc2007 = tsc2007;

    if (!tsc2007 || !input_dev) {
        ret = -ENOMEM;
        goto fail1;
    }

    i2c_set_clientdata(client, tsc2007);

    tsc2007->dev = input_dev;

    input_dev->name = "tsc2007";
    input_dev->phys = "tsc2007/input0";

    //input_dev->id.bustype = BUS_HOST;
    input_dev->dev.parent = &client->dev;

    __set_bit(EV_KEY, input_dev->evbit);
    __set_bit(BTN_TOUCH, input_dev->keybit);

    __set_bit(EV_ABS, input_dev->evbit);
    __set_bit(ABS_PRESSURE, input_dev->evbit);
    __set_bit(ABS_X, input_dev->evbit);
    __set_bit(ABS_Y, input_dev->evbit);

    input_set_abs_params(input_dev, ABS_X, x_min, x_max, 0, 0);
    input_set_abs_params(input_dev, ABS_Y, y_min, y_max, 0, 0);
    input_set_abs_params(input_dev, ABS_PRESSURE, 0, 255, 0, 0);

    ret = request_irq(client->irq, tsc2007_interrupt, 
        IRQF_DISABLED | IRQF_TRIGGER_FALLING,
         "tsc2007 irq", NULL);
    if (ret){
        printk(KERN_ERR "tsc2007 request irq failed/n");
        goto fail2;
    }

    ret = input_register_device(tsc2007->dev);
    if (ret){
        printk(KERN_ERR "tsc2007 register device fail/n");
        goto fail2;
    }

    /*init */
    tsc2007->status = PEN_UP;
    tsc2007->client = client;
    tsc2007->last_touch = jiffies;

    INIT_WORK(&tsc2007->irq_work, tsc2007_irq_work);

    /* init tsc2007 */
    i2c_smbus_write_byte(client, TSC_CMD_SETUP);

    return 0;

 fail2:
    free_irq(client->irq, client);
 fail1:
    i2c_set_clientdata(client, NULL);
    input_free_device(input_dev);
    kfree(tsc2007);
    return ret;
}

static int __devexit tsc2007_remove(struct i2c_client *client)
{
    struct _tsc2007 *tsc2007 = i2c_get_clientdata(client);

    if(client->irq)
        free_irq(client->irq, client);
    
    i2c_set_clientdata(client, NULL);
    input_unregister_device(tsc2007->dev);
    kfree(tsc2007);

    return 0;
}

static struct i2c_device_id tsc2007_idtable[] = { 
    { "tsc2007", 0 }, 
    { } 
}; 

MODULE_DEVICE_TABLE(i2c, tsc2007_idtable);

static struct i2c_driver tsc2007_driver = {
    .driver = {
        .name     = "tsc2007",
    },
    .id_table       = tsc2007_idtable,
    .probe        = tsc2007_probe,
    .remove        = __devexit_p(tsc2007_remove),
};

static int __init tsc2007_ts_init(void)
{
    init_sysctl();
    return i2c_add_driver(&tsc2007_driver);     
}

static void __exit tsc2007_ts_exit(void)
{
    cleanup_sysctl();
    i2c_del_driver(&tsc2007_driver);
}

module_init(tsc2007_ts_init);
module_exit(tsc2007_ts_exit);

MODULE_DESCRIPTION("tsc2007 touch screen driver");
MODULE_LICENSE("GPL");

(1)切换至tslib目录然后执行如下命令(以marvell平台为例)
./autogen.sh
echo "ac_cv_func_malloc_0_nonnull=yes" > arm-marvell-linux.cache
./configure --host=arm-marvell-linux-gnueabi --prefix=/work/svn/ts_build --cache-file=arm-marvell-linux.cache
上面三步仅仅是为了取得tslib目录下的config.h文件

(2)将tslib复制到android源代码vendor/<company_name>/<board_name>目录下

(3)修改vendor/<company_name>/<board_name>目录下的AndroidBoard.mk文件，加入如下内容
include $(LOCAL_PATH)/tslib/Mdroid.mk
一定要主义LOCAL_PATH这个宏的时效性

(4)在tslib目录下创建Mdroid.mk，内容如下：
LOCAL_PATH:= $(call my-dir)
include $(CLEAR_VARS)

TS_PATH := $(LOCAL_PATH)

include $(TS_PATH)/src/Mdroid.mk
include $(TS_PATH)/plugins/Mdroid.mk
include $(TS_PATH)/tests/Mdroid.mk

include $(CLEAR_VARS)
file := $(TARGET_OUT_ETC)/ts.conf
$(file) : $(TS_PATH)/etc/ts.conf | $(ACP)
    $(transform-prebuilt-to-target)
ALL_PREBUILT += $(file)


(5)在tslib/src目录下创建Mdroid.mk，内容如下：
LOCAL_PATH:= $(call my-dir)
include $(CLEAR_VARS)

LOCAL_SRC_FILES:= ts_attach.c ts_close.c ts_config.c /
    ts_error.c ts_fd.c ts_load_module.c ts_open.c ts_parse_vars.c /
    ts_read.c ts_read_raw.c ts_option.c

LOCAL_C_INCLUDES += /
        $(LOCAL_PATH)/../

LOCAL_SHARED_LIBRARIES += libutils libcutils

LOCAL_SHARED_LIBRARIES += libdl
LOCAL_PRELINK_MODULE := false
LOCAL_MODULE := libts

include $(BUILD_SHARED_LIBRARY)


(6)在tslib/plugins目录下创建Mdroid.mk，内容如下：
LOCAL_PATH:= $(call my-dir)
include $(CLEAR_VARS)

LOCAL_SRC_FILES:= input-raw.c

LOCAL_C_INCLUDES += /
        $(LOCAL_PATH)/../ /
        $(LOCAL_PATH)/../src

LOCAL_SHARED_LIBRARIES := libts
LOCAL_MODULE := input
LOCAL_PRELINK_MODULE := false
include $(BUILD_SHARED_LIBRARY)


include $(CLEAR_VARS)
LOCAL_SRC_FILES:= pthres.c

LOCAL_C_INCLUDES += /
        $(LOCAL_PATH)/../ /
        $(LOCAL_PATH)/../src

LOCAL_SHARED_LIBRARIES := libts
LOCAL_MODULE := pthres
LOCAL_PRELINK_MODULE := false
include $(BUILD_SHARED_LIBRARY)


include $(CLEAR_VARS)
LOCAL_SRC_FILES:= variance.c

LOCAL_C_INCLUDES += /
        $(LOCAL_PATH)/../ /
        $(LOCAL_PATH)/../src

LOCAL_SHARED_LIBRARIES := libts
LOCAL_MODULE := variance
LOCAL_PRELINK_MODULE := false
include $(BUILD_SHARED_LIBRARY)


include $(CLEAR_VARS)
LOCAL_SRC_FILES:= dejitter.c

LOCAL_C_INCLUDES += /
        $(LOCAL_PATH)/../ /
        $(LOCAL_PATH)/../src

LOCAL_SHARED_LIBRARIES := libts
LOCAL_MODULE := dejitter
LOCAL_PRELINK_MODULE := false
include $(BUILD_SHARED_LIBRARY)

include $(CLEAR_VARS)
LOCAL_SRC_FILES:= linear.c

LOCAL_C_INCLUDES += /
        $(LOCAL_PATH)/../ /
        $(LOCAL_PATH)/../src

LOCAL_SHARED_LIBRARIES := libts
LOCAL_MODULE := linear
LOCAL_PRELINK_MODULE := false
include $(BUILD_SHARED_LIBRARY)


(7)在tslib/tests目录下创建Mdroid.mk，内容如下：
LOCAL_PATH:= $(call my-dir)
include $(CLEAR_VARS)

LOCAL_SRC_FILES:= ts_calibrate.c fbutils.c testutils.c font_8x8.c font_8x16.c

LOCAL_C_INCLUDES += /
        $(LOCAL_PATH)/../ /
        $(LOCAL_PATH)/../src

LOCAL_SHARED_LIBRARIES := libts

LOCAL_SHARED_LIBRARIES += libutils libcutils

LOCAL_MODULE := tscalibrate

include $(BUILD_EXECUTABLE)


(8)在tslib/config.h文件中加入如下定义：
#define TS_CONF  "/system/etc/ts.conf"
#define PLUGIN_DIR "/system/lib"
#define TS_POINTERCAL "/data/etc/pointercal"


(9)将下面路径文件
tslib/src/ts_open.c
tslib/tests/ts_calibrate.c
tslib/tests/fbutils.c
中的
#include <sys/fcntl.h>
修改成
#include <fcntl.h>

(10)将tslib/tests/ts_calibrate.c文件中
static int clearbuf(struct tsdev *ts)
修改为
static void clearbuf(struct tsdev *ts)

(11)修改tslib/etc/ts.conf内容如下：
module_raw input
module pthres pmin=1
module variance delta=30
module dejitter delta=100
module linear

(12)在android源代码init.rc中声明tslib相关的宏如下：
# touchscreen parameters
    export TSLIB_FBDEVICE /dev/graphics/fb0
    export TSLIB_CALIBFILE /data/etc/pointercal
    export TSLIB_CONFFILE  /system/etc/ts.conf
    export TSLIB_TRIGGERDEV /dev/input/event0
    export TSLIB_TSDEVICE /dev/input/event1

(13)重新编译后即可调用tscalibrate命令来校验触摸屏，校验后产生一个/data/etc/pointercal文件