Header Files

For the above example, at least the following include files are necessary.


  #include <linux/init.h>
  #include <linux/pci.h>
  #include <linux/slab.h>
  #include <sound/core.h>
  #include <sound/initval.h>

          

In addition to these headers, you'll need <linux/interrupt.h> for interrupt handling, and <asm/io.h> for I/O access. If you use the mdelay() or udelay() functions, you'll need to include <linux/delay.h> too.

The ALSA interfaces like the PCM and control APIs are defined in other <sound/xxx.h> header files. They have to be included after <sound/core.h>.