#include uint8_t io_in8(uint16_t port) { uint8_t r; asm volatile("inb %1, %0" : "=a"(r) : "dN"(port)); return r; } void io_out8(uint16_t port, uint8_t value) { asm volatile("outb %1, %0" :: "dN"(port), "a"(value)); } uint16_t io_in16(uint16_t port) { uint16_t r; asm volatile("in %%dx, %%ax" : "=a"(r) : "d"(port)); return r; } void io_out16(uint16_t port, uint16_t value) { asm volatile("out %%ax, %%dx" :: "a"(value), "d"(port)); } uint32_t io_in32(uint16_t port) { uint32_t r; asm volatile("inl %%dx, %%eax" : "=a"(r) : "d"(port)); return r; } void io_out32(uint16_t port, uint32_t value) { asm volatile("outl %%eax, %%dx" :: "d"(port), "a"(value)); }