include/asm/io.h


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/*
 * asm/io.h
 *
 * Provides access to x86 I/O functions
 */

#define inb(port) ({ \
  unsigned char _val; \
  __asm__ volatile ("inb %%dx, %%al" : "=a" (_val) : "d" (port)); \
  _val; \
  })

#define inw(port) ({ \
  unsigned short _val; \
  __asm__ volatile ("inw %%dx, %%ax" : "=a" (_val) : "d" (port)); \
  _val; \
  })

#define outb(port, val) \
  __asm__ volatile ("outb %%al, %%dx" :: "d" (port), "a" (val));

#define outw(port, val) \
  __asm__ volatile ("outw %%ax, %%dx" :: "d" (port), "a" (val));