OK6410（256M RAM ，1G SLC NAND）Linux-3.8.3驱动（9.2）TS驱动2

现在来使用ADC来转换转换x轴和y轴坐标，并打印出来
代码如下

#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/input.h>
#include <linux/init.h>
#include <linux/serio.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/clk.h>

#include <asm/io.h>
#include <asm/irq.h>
#include <mach/hardware.h>

#include <plat/regs-adc.h>
#include <mach/ts.h>
#include <mach/irqs.h>

struct ts_regs{
    unsigned long adccon;
    unsigned long adctsc;
    unsigned long adcdly;
    unsigned long adcdat0;
    unsigned long adcdat1;
    unsigned long adcupdn;
    unsigned long adcclrint;
    unsigned long reserverd;
    unsigned long adcclrintpndnup;
};

static volatile struct ts_regs *ts_regs;

static struct input_dev *ts_dev;

static void enter_wait_pen_down_mode(void)//等待中断模式
{
    ts_regs->adctsc = 0xd3;//adctsc寄存器的bit-8为0时，Detect Stylus Down Interrupt Signal
}

static void enter_wait_pen_up_mode(void)//等待中断模式
{
    ts_regs->adctsc = 0x1d3;//adctsc寄存器的bit-8为1时，Detect Stylus Up Interrupt Signal
}

static void enter_measure_xy_mode(void)//自动测量x/y座标模式
{
    ts_regs->adctsc = (1<<3)|(1<<2);
}

static void start_adc(void)//启动ADC
{
    ts_regs->adccon |= (1<<0);
}

static irqreturn_t pen_down_up_irq(int irq, void *dev_id)
{
    if (ts_regs->adcdat0 & (1<<15))//如果寄存器adcdat0的bit-15值为1,说明触摸笔松开
    {
        printk("pen up\n");
        enter_wait_pen_down_mode();//Detect Stylus Down Interrupt Signal，检查触笔落下中断
    }
    else
    {
        printk("pen down\n");
        //enter_wait_pen_up_mode();//Detect Stylus Up Interrupt Signal，检查触笔松开中断
        enter_measure_xy_mode();/* 进入"自动测量x/y座标模式" */
        start_adc();/* 启动ADC */
    }

    ts_regs->adcupdn = 0;//Stylus Up/Down Interrupt history. (After check, this bit should be cleared manually)
    ts_regs->adcclrint = 1;// 产生adc中断后要清除adc中断，给寄存器adcclrint赋任意值都能清除adc中断
    ts_regs->adcclrintpndnup = 1;// 产生up/down中断后要清除up/down中断，给寄存器adcclrintpndnup赋任意值都能清除up/down中断

    return IRQ_HANDLED;
}

static irqreturn_t adc_irq(int irq, void *dev_id)
{
    int x,y;
    int adcdat0,adcdat1;

    adcdat0 = ts_regs->adcdat0;
    adcdat1 = ts_regs->adcdat1;

    x = adcdat0 & 0xfff;
    y = adcdat1 & 0xfff;

    printk("x = %d, y = %d\n", x, y);
    enter_wait_pen_up_mode();//Detect Stylus Up Interrupt Signal，检查触笔松开中断

    ts_regs->adcupdn = 0;//Stylus Up/Down Interrupt history. (After check, this bit should be cleared manually)
    ts_regs->adcclrint = 1 ;// 产生adc中断后要清除adc中断，给寄存器adcclrint赋任意值都能清除adc中断
    ts_regs->adcclrintpndnup = 1;// 产生up/down中断后要清除up/down中断，给寄存器adcclrintpndnup赋任意值都能清除up/down中断

    return IRQ_HANDLED;
}

static int ts_init(void)
{
    struct clk *clk;

    /* 1. 分配input_dev */
    ts_dev = input_allocate_device();

    /* 2. 设置 */
    /* 2.1 能产生哪类事件 */
    set_bit(EV_KEY, ts_dev->evbit);//能产生按键类事件
    set_bit(EV_ABS, ts_dev->evbit);//能产生绝对位移事件
    /* 2.2 能产生这类事件里的哪些事件 */
    set_bit(BTN_TOUCH, ts_dev->keybit);//能产生按键类里面的触摸屏事件
    input_set_abs_params(ts_dev, ABS_X, 0, 0xFFF, 0, 0);
    input_set_abs_params(ts_dev, ABS_Y, 0, 0xFFF, 0, 0);
    input_set_abs_params(ts_dev, ABS_PRESSURE, 0, 1, 0, 0);

    /* 3. 注册 */
    if( input_register_device(ts_dev) )
        return -EFAULT;

    /* 4.硬件相关操作 */
    //4.1使能时钟
    clk = clk_get(NULL, "adc");
    clk_enable(clk);/* PCLK_GATE[12]设为1 */
    //4.2设置s3c6410的ADC/TS寄存器
    ts_regs = ioremap(0x7E00B000, sizeof(struct ts_regs));
    /* bit[16] : 1 = 12-bit A/D conversion
     * bit[14] : 1-A/D converter prescaler enable
     * bit[13:6]: A/D converter prescaler value,
     * 13, ADCCLK=PCLK/(13+1)=66MHz/(13+1)=4.75MHz,最高支持5Mhz
     * bit[2]: 设为0
     * bit[0]: A/D conversion starts by enable. 先设为0
     */
    ts_regs->adccon =(1<<16) | (1<<14) | (13<<6);

    ts_regs->adcclrintpndnup = 1;//Clear Pen Down/Up Interrupt,给寄存器adcclrintpndnup赋任意值都能清除up/down中断

    if ( request_irq(IRQ_PENDN, pen_down_up_irq, IRQF_SAMPLE_RANDOM, "ts_pen", NULL) )
        return -EFAULT;

    if ( request_irq(IRQ_ADC, adc_irq, IRQF_SAMPLE_RANDOM, "adc", NULL) )
        return -EFAULT;

    /* 进入"wait for interrupt mode", 等待触摸笔按下或松开的模式 */
    enter_wait_pen_down_mode();

    return 0;
}

static void ts_exit(void)
{
    free_irq(IRQ_PENDN, NULL);
    free_irq(IRQ_ADC, NULL);
    iounmap(ts_regs);
    input_unregister_device(ts_dev);
    input_free_device(ts_dev);
}

module_init(ts_init);
module_exit(ts_exit);
MODULE_LICENSE("GPL");