linux2.6.30.4 内核移植（2）触摸屏驱动

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

/* For ts.dev.id.version */
#define S3C2410TSVERSION	0x0101

#define WAIT4INT(x)  (((x)<<8) | /
S3C2410_ADCTSC_YM_SEN | S3C2410_ADCTSC_YP_SEN | S3C2410_ADCTSC_XP_SEN | /
S3C2410_ADCTSC_XY_PST(3))

#define AUTOPST	     (S3C2410_ADCTSC_YM_SEN | S3C2410_ADCTSC_YP_SEN | S3C2410_ADCTSC_XP_SEN | /
S3C2410_ADCTSC_AUTO_PST | S3C2410_ADCTSC_XY_PST(0))

static char *s3c2410ts_name = "s3c2410 TouchScreen";

static	struct input_dev *dev;
static	long xp;
static	long yp;
static	int count;

static struct semaphore ADC_LOCK;
static int OwnADC = 0;

static void __iomem *base_addr;

static inline void s3c2410_ts_connect(void)
{
s3c2410_gpio_cfgpin(S3C2410_GPG12, S3C2410_GPG12_XMON);
s3c2410_gpio_cfgpin(S3C2410_GPG13, S3C2410_GPG13_nXPON);
s3c2410_gpio_cfgpin(S3C2410_GPG14, S3C2410_GPG14_YMON);
s3c2410_gpio_cfgpin(S3C2410_GPG15, S3C2410_GPG15_nYPON);
}

static void touch_timer_fire(unsigned long data)
{
unsigned long data0;
unsigned long data1;
int updown;

data0 = ioread32(base_addr+S3C2410_ADCDAT0);
data1 = ioread32(base_addr+S3C2410_ADCDAT1);

updown = (!(data0 & S3C2410_ADCDAT0_UPDOWN)) && (!(data1 & S3C2410_ADCDAT0_UPDOWN));

if (updown) {
if (count != 0) {
long tmp;

tmp = xp;
xp = yp;
yp = tmp;

/*取4次平均值*/
xp >>= 2;
yp >>= 2;

/*上报坐标*/
input_report_abs(dev, ABS_X, xp);
input_report_abs(dev, ABS_Y, yp);

input_report_key(dev, BTN_TOUCH, 1);
input_report_abs(dev, ABS_PRESSURE, 1);
input_sync(dev);
}

xp = 0;
yp = 0;
count = 0;

/* 启动AD 转换*/
iowrite32(S3C2410_ADCTSC_PULL_UP_DISABLE | AUTOPST, base_addr+S3C2410_ADCTSC);
iowrite32(ioread32(base_addr+S3C2410_ADCCON) | S3C2410_ADCCON_ENABLE_START, base_addr+S3C2410_ADCCON);
} else {
count = 0;

input_report_key(dev, BTN_TOUCH, 0);
input_report_abs(dev, ABS_PRESSURE, 0);
input_sync(dev);

iowrite32(WAIT4INT(0), base_addr+S3C2410_ADCTSC);
if (OwnADC) {
OwnADC = 0;
up(&ADC_LOCK);
}
}
}

static struct timer_list touch_timer =
TIMER_INITIALIZER(touch_timer_fire, 0, 0);

static irqreturn_t stylus_updown(int irq, void *dev_id)
{
unsigned long data0;
unsigned long data1;
int updown;

if (down_trylock(&ADC_LOCK) == 0) {
OwnADC = 1;
data0 = ioread32(base_addr+S3C2410_ADCDAT0);
data1 = ioread32(base_addr+S3C2410_ADCDAT1);

/*updown ==1, 按下OR  弹起???*/
updown = (!(data0 & S3C2410_ADCDAT0_UPDOWN)) && (!(data1 & S3C2410_ADCDAT0_UPDOWN));

if (updown) {
touch_timer_fire(0);
} else {
OwnADC = 0;
up(&ADC_LOCK);
}
}

return IRQ_HANDLED;
}

static irqreturn_t stylus_action(int irq, void *dev_id)
{
unsigned long data0;
unsigned long data1;

if (OwnADC) {
data0 = ioread32(base_addr+S3C2410_ADCDAT0);
data1 = ioread32(base_addr+S3C2410_ADCDAT1);

xp += data0 & S3C2410_ADCDAT0_XPDATA_MASK;
yp += data1 & S3C2410_ADCDAT1_YPDATA_MASK;
count++;

if (count < (1<<2)) {
/* 再一次启动AD转换*/
iowrite32(S3C2410_ADCTSC_PULL_UP_DISABLE | AUTOPST, base_addr+S3C2410_ADCTSC);
iowrite32(ioread32(base_addr+S3C2410_ADCCON) | S3C2410_ADCCON_ENABLE_START, base_addr+S3C2410_ADCCON);
} else {
mod_timer(&touch_timer, jiffies+1);
iowrite32(WAIT4INT(1), base_addr+S3C2410_ADCTSC);
}
}

return IRQ_HANDLED;
}

static struct clk	*adc_clock;

static int __init s3c2410ts_init(void)
{
struct input_dev *input_dev;
init_MUTEX(&ADC_LOCK);
adc_clock = clk_get(NULL, "adc");
if (!adc_clock) {
printk(KERN_ERR "failed to get adc clock source/n");
return -ENOENT;
}
clk_enable(adc_clock);

base_addr=ioremap(S3C2410_PA_ADC,0x20);
if (base_addr == NULL) {
printk(KERN_ERR "Failed to remap register block/n");
return -ENOMEM;
}

/* Configure GPIOs */
s3c2410_ts_connect();

iowrite32(S3C2410_ADCCON_PRSCEN | S3C2410_ADCCON_PRSCVL(0xFF),/
base_addr+S3C2410_ADCCON);
iowrite32(0xffff,  base_addr+S3C2410_ADCDLY);
iowrite32(WAIT4INT(0), base_addr+S3C2410_ADCTSC);

/* Initialise input stuff */
input_dev = input_allocate_device();

if (!input_dev) {
printk(KERN_ERR "Unable to allocate the input device !!/n");
return -ENOMEM;
}

dev = input_dev;
dev->evbit[0] = BIT(EV_SYN) | BIT(EV_KEY) | BIT(EV_ABS);
dev->keybit[BITS_TO_LONGS(BTN_TOUCH)] = BIT(BTN_TOUCH);
input_set_abs_params(dev, ABS_X, 0, 0x3FF, 0, 0);
input_set_abs_params(dev, ABS_Y, 0, 0x3FF, 0, 0);
input_set_abs_params(dev, ABS_PRESSURE, 0, 1, 0, 0);

dev->name = s3c2410ts_name;
dev->id.bustype = BUS_RS232;
dev->id.vendor = 0xDEAD;
dev->id.product = 0xBEEF;
dev->id.version = S3C2410TSVERSION;

/* Get irqs */
if (request_irq(IRQ_ADC, stylus_action, IRQF_SHARED|IRQF_SAMPLE_RANDOM,
"s3c2410_action", dev)) {
printk(KERN_ERR "s3c2410_ts.c: Could not allocate ts IRQ_ADC !/n");
iounmap(base_addr);
return -EIO;
}
if (request_irq(IRQ_TC, stylus_updown, IRQF_SAMPLE_RANDOM,
"s3c2410_action", dev)) {
printk(KERN_ERR "s3c2410_ts.c: Could not allocate ts IRQ_TC !/n");
iounmap(base_addr);
return -EIO;
}

printk(KERN_INFO "%s successfully loaded/n", s3c2410ts_name);

/* All went ok, so register to the input system */
input_register_device(dev);

return 0;
}

static void __exit s3c2410ts_exit(void)
{
disable_irq(IRQ_ADC);
disable_irq(IRQ_TC);
free_irq(IRQ_TC,dev);
free_irq(IRQ_ADC,dev);

if (adc_clock) {
clk_disable(adc_clock);
clk_put(adc_clock);
adc_clock = NULL;
}

input_unregister_device(dev);
iounmap(base_addr);
}

module_init(s3c2410ts_init);
module_exit(s3c2410ts_exit);