* The function is provided primarily for OSS layer and USB gadget drivers,
* and it allows only the limited set of ioctls (hw_params, sw_params,
* prepare, start, drain, drop, forward).
+ *
+ * Return: zero if successful, or a negative error code
*/
int snd_pcm_kernel_ioctl(struct snd_pcm_substream *substream,
unsigned int cmd, void *arg)
*
* This is the default mmap handler for PCM data. When mmap pcm_ops is NULL,
* this function is invoked implicitly.
+ *
+ * Return: zero if successful, or a negative error code
*/
int snd_pcm_lib_default_mmap(struct snd_pcm_substream *substream,
struct vm_area_struct *area)
* When your hardware uses the iomapped pages as the hardware buffer and
* wants to mmap it, pass this function as mmap pcm_ops. Note that this
* is supposed to work only on limited architectures.
+ *
+ * Return: zero if successful, or a negative error code
*/
int snd_pcm_lib_mmap_iomem(struct snd_pcm_substream *substream,
struct vm_area_struct *area)