2016-01-19 16:12, Yuanhan Liu:

+#define IO_READ_DEF(nr_bits, type)             \
+static inline type                             \
+io_read##nr_bits(type *addr)                   \
+{                                              \
+       return *(volatile type *)addr;          \
+}
+
+#define IO_WRITE_DEF(nr_bits, type)            \
+static inline void                             \
+io_write##nr_bits(type val, type *addr)                \
+{                                              \
+       *(volatile type *)addr = val;           \
+}
+
+IO_READ_DEF (8, uint8_t)
+IO_WRITE_DEF(8, uint8_t)
+
+IO_READ_DEF (16, uint16_t)
+IO_WRITE_DEF(16, uint16_t)
+
+IO_READ_DEF (32, uint32_t)
+IO_WRITE_DEF(32, uint32_t)

Yes you can do this.
But not sure you should.

+static inline void
+io_write64_twopart(uint64_t val, uint32_t *lo, uint32_t *hi)
+{
+       io_write32(val & ((1ULL << 32) - 1), lo);
+       io_write32(val >> 32,                hi);
+}

When debugging this code, how GDB behave?
How to find the definition of io_write32() with grep or simple editors?