[alsa-devel] [RFC 3/5] compress: add API header and driver header files

Clemens Ladisch clemens at ladisch.de
Fri Sep 2 15:36:23 CEST 2011

Vinod Koul wrote:
> +#define SNDRV_COMPRESS_GET_CAPS		_IOWR('C', 0x00, struct snd_compr_caps *)
> +#define SNDRV_COMPRESS_GET_CODEC_CAPS	_IOWR('C', 0x01, struct snd_compr_codec_caps *)
> +#define SNDRV_COMPRESS_SET_PARAMS	_IOW('C', 0x02, struct snd_compr_params *)
> +#define SNDRV_COMPRESS_GET_PARAMS	_IOR('C', 0x03, struct snd_compr_params *)
> +#define SNDRV_COMPRESS_TSTAMP		_IOR('C', 0x10, struct snd_compr_tstamp *)
> +#define SNDRV_COMPRESS_AVAIL		_IOR('C', 0x11, struct snd_compr_avail *)

The type whose size is made part of the ioctl number is supposed to be
the actual structure, not a pointer to it.

> +#define SNDRV_COMPRESS_PAUSE		_IO('C', 0x20)
> +#define SNDRV_COMPRESS_RESUME		_IO('C', 0x21)
> +#define SNDRV_COMPRESS_START		_IO('C', 0x22)
> +#define SNDRV_COMPRESS_STOP		_IO('C', 0x23)
> +#define SNDRV_COMPRESS_DRAIN		_IO('C', 0x24)

Please update Documentation/ioctl/ioctl-number.txt.
(This also makes it easier to pick codes without conflicts.)


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