Dne 18. 04. 21 v 17:12 David Henningsson napsal(a):
> +#define SND_RAWMIDI_FRAMING_DATA_LENGTH 16
SNDRV_ prefix should be here.
> +
> +struct snd_rawmidi_framing_tstamp {
> + /* For now, frame_type is always 0. Midi 2.0 is expected to add new
> + * types here. Applications are expected to skip unknown frame types.
> + */
> + u8 frame_type;
> + u8 length; /* number of valid bytes in data field */
> + u8 reserved[2];
> + u32 tv_nsec; /* nanoseconds */
> + u64 tv_sec; /* seconds */
> + u8 data[SND_RAWMIDI_FRAMING_DATA_LENGTH];
What about to move the fields to union (except for frame_type) like we do for
'struct snd_ctl_event' in case when we need to reorganize the contents for
future types?
> +};
> +
> struct snd_rawmidi_params {
> int stream;
> size_t buffer_size; /* queue size in bytes */
> size_t avail_min; /* minimum avail bytes for wakeup */
> unsigned int no_active_sensing: 1; /* do not send active sensing byte in close() */
> - unsigned char reserved[16]; /* reserved for future use */
> + unsigned char framing; /* For input data only, frame incoming data */
> + unsigned char clock_type; /* Type of clock to use for framing, same as clockid_t */
> + unsigned char reserved[14]; /* reserved for future use */
As I noted, I would prefer to add 'unsigned int mode;' and define
SNDRV_RAWMID_MODE_XXX bit flags and groups with framing and clock_type groups.
There's no reason to stick with 'clockid_t' (which is integer anyway). We're
using just a subset.
#define SNDRV_RAWMIDI_MODE_FRAMING_MASK (7<<0)
#define SNDRV_RAWMIDI_MODE_FRAMING_SHIFT 0
#define SNDRV_RAWMIDI_MODE_FRAMING_NONE (0<<0)
#define SNDRV_RAWMIDI_MODE_FRAMING_32BYTES (1<<0)
#define SNDRV_RAWMIDI_MODE_CLOCK_MASK (7<<3)
#define SNDRV_RAWMIDI_MODE_CLOCK_SHIFT 3
#define SNDRV_RAWMIDI_MODE_CLOCK_NONE (0<<3)
#define SNDRV_RAWMIDI_MODE_CLOCK_REALTIME (1<<3)
#define SNDRV_RAWMIDI_MODE_CLOCK_MONOTONIC (2<<3)
#define SNDRV_RAWMIDI_MODE_CLOCK_MONOTONIC_RAW (3<<3)
In this case, we can use 26-bits in future for extensions.
> +struct timespec64 get_framing_tstamp(struct snd_rawmidi_substream *substream)
> +{
> + struct timespec64 ts64 = {0, 0};
> +
> + if (substream->framing != SNDRV_RAWMIDI_FRAMING_TSTAMP)
> + return ts64;
> + if (substream->clock_type == CLOCK_MONOTONIC_RAW)
> + ktime_get_raw_ts64(&ts64);
> + else
> + ktime_get_ts64(&ts64);
> + return ts64;
> +}
Missing the realtime clock type here.
Jaroslav
--
Jaroslav Kysela <perex@xxxxxxxx>
Linux Sound Maintainer; ALSA Project; Red Hat, Inc.
