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:
viewplain
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:
viewplain
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:
viewplain
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:
viewplain
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:
viewplain
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:
viewplain
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:
viewplain
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:
viewplain
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);