include/linux/scx200_gpio.h

Source file repositories/reference/linux-study-clean/include/linux/scx200_gpio.h

File Facts

System
Linux kernel
Corpus path
include/linux/scx200_gpio.h
Extension
.h
Size
2438 bytes
Lines
90
Domain
Core OS
Bucket
Core Kernel Interface
Inferred role
Core OS: implementation source
Status
source implementation candidate

Why This File Exists

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.

Dependency Surface

Detected Declarations

Annotated Snippet

static inline int scx200_gpio_get(unsigned index) {
	__SCx200_GPIO_BANK;
	__SCx200_GPIO_IOADDR + 0x04;
	__SCx200_GPIO_INDEX;
		
	return (inl(ioaddr) & (1<<index)) ? 1 : 0;
}

/* return the value driven on the GPIO signal (the value that will be
   driven if the GPIO is configured as an output, it might not be the
   state of the GPIO right now if the GPIO is configured as an input) */

static inline int scx200_gpio_current(unsigned index) {
        __SCx200_GPIO_BANK;
	__SCx200_GPIO_INDEX;
		
	return (scx200_gpio_shadow[bank] & (1<<index)) ? 1 : 0;
}

/* drive the GPIO signal high */

static inline void scx200_gpio_set_high(unsigned index) {
	__SCx200_GPIO_BANK;
	__SCx200_GPIO_IOADDR;
	__SCx200_GPIO_SHADOW;
	__SCx200_GPIO_INDEX;
	set_bit(index, shadow);	/* __set_bit()? */
	__SCx200_GPIO_OUT;
}

/* drive the GPIO signal low */

static inline void scx200_gpio_set_low(unsigned index) {
	__SCx200_GPIO_BANK;
	__SCx200_GPIO_IOADDR;
	__SCx200_GPIO_SHADOW;
	__SCx200_GPIO_INDEX;
	clear_bit(index, shadow); /* __clear_bit()? */
	__SCx200_GPIO_OUT;
}

/* drive the GPIO signal to state */

static inline void scx200_gpio_set(unsigned index, int state) {
	__SCx200_GPIO_BANK;
	__SCx200_GPIO_IOADDR;
	__SCx200_GPIO_SHADOW;
	__SCx200_GPIO_INDEX;
	if (state)
		set_bit(index, shadow);
	else
		clear_bit(index, shadow);
	__SCx200_GPIO_OUT;
}

/* toggle the GPIO signal */
static inline void scx200_gpio_change(unsigned index) {
	__SCx200_GPIO_BANK;
	__SCx200_GPIO_IOADDR;
	__SCx200_GPIO_SHADOW;
	__SCx200_GPIO_INDEX;
	change_bit(index, shadow);
	__SCx200_GPIO_OUT;
}

#undef __SCx200_GPIO_BANK
#undef __SCx200_GPIO_IOADDR
#undef __SCx200_GPIO_SHADOW
#undef __SCx200_GPIO_INDEX
#undef __SCx200_GPIO_OUT

Annotation

Implementation Notes