Documenting the Source Code

All source code items such as functions, globals, and defines must be documented. Declarations that appear in the API headers must be documented.

The source code documentation follows the Doxygen (dox) annotation format. It enables generation of documentation in HTML/XML formats directly from the annotated source files. Doxygen has many annotation flavors; the FW code uses the one used by Alsa Project.

Refer to SOF Documentation Generation to learn how to generate the documentation.

Basic Rules

  1. All dox comments begin with /** and end with */.

  2. Short comments appended to structure members begin with /**<. Keep them short while adding more details to the parent documentation if needed.

  3. If a brief description is followed by a detailed description, the first one begins with the \brief tag and the detailed section is separated with an empty line.

  4. Use the \brief tag if you want to make sure the first line is inlined inside the basic description in HTML output (see #define example below).

Examples

Code Block 11 General Example
/**
 * \brief This is mandatory short description.
 *
 * This is detailed description.
 */
 typedef ...;
Code Block 12 Macro (simple one, with no parameters)
/** \brief SOF ABI version number. */
#define SOF_ABI_VERSION 1
Code Block 13 Structure / Union
/**
 * \brief Header for all non IPC ABI data.
 *
 * Identifies data type, size and ABI.
 * Used by any bespoke component data structures or binary blobs.
 */
struct sof_abi_hdr {
  uint32_t magic;     /**< 'S', 'O', 'F', '\0' */
  uint32_t type;      /**< component specific type */
  uint32_t size;      /**< size in bytes of data excluding this struct */
  uint32_t abi;       /**< SOF ABI version */
  uint32_t comp_abi;  /**< component specific ABI version */
  char data[0];
} __attribute__((packed));
Code Block 14 Enum
/** \brief Types of DAI */
enum sof_ipc_dai_type {
 SOF_DAI_INTEL_NONE = 0, /**< None */
 SOF_DAI_INTEL_SSP,      /**< Intel SSP */
 SOF_DAI_INTEL_DMIC,     /**< Intel DMIC */
 SOF_DAI_INTEL_HDA,      /**< Intel HDA */
};
Code Block 15 Function / Macro (with parameters)
/**
* \brief Utility to get module pointer from position.
* \param[in,out] desc FW descriptor in manifest.
* \param[in] index Index of the module.
* \return Pointer to module descriptor.
*
* Note that index is not verified.
*/
static inline struct sof_man_module *sof_man_get_module(struct sof_man_fw_desc *desc,
                                                        int index);