s3c2410_gpio_setpin()等系列函数

系列函数
系列函数的定义在arch/arm/mach-s3c2410/gpio.c，相关的宏定义在include/asm-arm/arch-s3c2410/regs-gpio.h

（1）voids3c2410_gpio_setpin(unsigned int pin, unsigned intto);

设置相应GPIO口的输出值，例如：

pin=S3C2410_GPG2，to=0，则设置S3C2410＿GPG2的输出值为0；

pin=S3C2410_GPG2，to=1，则设置S3C2410＿GPG2的输出值为1。

函数定义：

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void s3c2410_gpio_setpin(unsigned int pin, unsigned int to)

{

void __iomem *base = S3C2410_GPIO_BASE(pin);

unsigned long offs = S3C2410_GPIO_OFFSET(pin);

unsigned long flags;

unsigned long dat;

local_irq_save(flags);

dat = __raw_readl(base + 0x04);

dat &= ~(1 << offs);

dat |= to << offs;

__raw_writel(dat, base + 0x04);

local_irq_restore(flags);

}

EXPORT_SYMBOL(s3c2410_gpio_setpin);

（2）unsigned int s3c2410_gpio_getpin(unsigned intpin);

获取相应GPIO口的值。

函数定义：

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unsigned int s3c2410_gpio_getpin(unsigned int pin)

{

void __iomem *base = S3C2410_GPIO_BASE(pin);

unsigned long offs = S3C2410_GPIO_OFFSET(pin);

return __raw_readl(base + 0x04) & (1<< offs);

}

EXPORT_SYMBOL(s3c2410_gpio_getpin);

（3）voids3c2410_gpio_cfgpin(unsigned int pin, unsigned intfunction);

设置相应GPIO口的工作模式，输入、输出、中断等。

函数定义：

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void s3c2410_gpio_cfgpin(unsigned int pin, unsigned int function)

{

void __iomem *base = S3C2410_GPIO_BASE(pin);

unsigned long mask;

unsigned long con;

unsigned long flags;

if (pin < S3C2410_GPIO_BANKB) {

mask = 1 << S3C2410_GPIO_OFFSET(pin);

} else {

mask = 3 << S3C2410_GPIO_OFFSET(pin)*2;

}

local_irq_save(flags);

con = __raw_readl(base + 0x00);

con &= ~mask;

con |= function;

__raw_writel(con, base + 0x00);

local_irq_restore(flags);

}

EXPORT_SYMBOL(s3c2410_gpio_cfgpin);

（4）unsignedint s3c2410_gpio_getcfg(unsigned int pin);
获取相应GPIO口的工作模式，输入、输出、中断等。

函数定义：

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unsigned int s3c2410_gpio_getcfg(unsigned int pin)

{

void __iomem *base = S3C2410_GPIO_BASE(pin);

unsigned long mask;

if (pin < S3C2410_GPIO_BANKB) {

mask = 1 << S3C2410_GPIO_OFFSET(pin);

} else {

mask = 3 << S3C2410_GPIO_OFFSET(pin)*2;

}

return __raw_readl(base) & mask;

}

EXPORT_SYMBOL(s3c2410_gpio_getcfg);

（5）voids3c2410_gpio_pullup(unsigned int pin, unsigned intto);

设置相应的GPIO口的电平，例如：

pin=S3C2410_GPG2，to=0，则拉低S3C2410_GPG2，也就是设置S3C2410＿GPG2的值为0；

pin=S3C2410_GPG2，to=1，则拉高S3C2410_GPG2，也就是设置S3C2410＿GPG2的值为1。

函数定义：

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void s3c2410_gpio_pullup(unsigned int pin, unsigned int to)

{

void __iomem *base = S3C2410_GPIO_BASE(pin);

unsigned long offs = S3C2410_GPIO_OFFSET(pin);

unsigned long flags;

unsigned long up;

if (pin < S3C2410_GPIO_BANKB)

return;

local_irq_save(flags);

up = __raw_readl(base + 0x08);

up &= ~(1L << offs);

up |= to << offs;

__raw_writel(up, base + 0x08);

local_irq_restore(flags);

}

EXPORT_SYMBOL(s3c2410_gpio_pullup);

（6）unsignedint s3c2410_modify_misccr(unsigned int clear, unsigned intchange);
杂项设置，设置寄存器MISCCR，具体看函数定义。

函数定义：

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unsigned int s3c2410_modify_misccr(unsigned int clear, unsigned int change)

{

unsigned long flags;

unsigned long misccr;

local_irq_save(flags);

misccr = __raw_readl(S3C2410_MISCCR);

misccr &= ~clear;

misccr ^= change;

__raw_writel(misccr, S3C2410_MISCCR);

local_irq_restore(flags);

return misccr;

}

EXPORT_SYMBOL(s3c2410_modify_misccr);

（7）ints3c2410_gpio_getirq(unsigned int pin);
获取相应的GPIO口所对应的中断号。

函数定义：

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int s3c2410_gpio_getirq(unsigned int pin)

{

if (pin < S3C2410_GPF0 || pin > S3C2410_GPG15_EINT23)

return -1;

if (pin < S3C2410_GPG0 && pin > S3C2410_GPF7)

return -1;

if (pin < S3C2410_GPF4)

return (pin - S3C2410_GPF0) + IRQ_EINT0;

if (pin < S3C2410_GPG0)

return (pin - S3C2410_GPF4) + IRQ_EINT4;

return (pin - S3C2410_GPG0) + IRQ_EINT8;

}

EXPORT_SYMBOL(s3c2410_gpio_getirq);

（8）ints3c2410_gpio_irqfilter(unsigned int pin, unsigned int on, unsignedint config);
中断过滤配置，具体看函数定义。

函数定义：

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int s3c2410_gpio_irqfilter(unsigned int pin, unsigned int on,

unsigned int config)

{

void __iomem *reg = S3C2410_EINFLT0;

unsigned long flags;

unsigned long val;

if (pin < S3C2410_GPG8 || pin > S3C2410_GPG15)

return -1;

config &= 0xff;

pin -= S3C2410_GPG8_EINT16;

reg += pin & ~3;

local_irq_save(flags);

val = __raw_readl(reg);

val &= ~(0xff << ((pin & 3) * 8));

val |= config << ((pin & 3) * 8);

__raw_writel(val, reg);

val = __raw_readl(S3C2410_EXTINT2);

val &= ~(1 << ((pin * 4) + 3));

val |= on << ((pin * 4) + 3);

__raw_writel(val, S3C2410_EXTINT2);

local_irq_restore(flags);

return 0;

}

EXPORT_SYMBOL(s3c2410_gpio_irqfilter);