From ff166a9d19fab3d77f50e9413df046fb1d7c01cc Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Tue, 23 May 2023 09:53:49 +0200 Subject: ALSA: seq: Add port direction to snd_seq_port_info Add a new field "direction" to snd_seq_port_info for allowing a client to tell the expected direction of the port access. A port might still allow subscriptions for read/write (e.g. for MIDI-CI) even if the primary usage of the port is a single direction (either input or output only). This new "direction" field can help to indicate such cases. When the direction is unspecified at creating a port and the port has either read or write capability, the corresponding direction bits are set automatically as default. Reviewed-by: Jaroslav Kysela Link: https://lore.kernel.org/r/20230523075358.9672-29-tiwai@suse.de Signed-off-by: Takashi Iwai --- include/uapi/sound/asequencer.h | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/uapi/sound/asequencer.h b/include/uapi/sound/asequencer.h index 67532c46b115..eae1e0b0bf37 100644 --- a/include/uapi/sound/asequencer.h +++ b/include/uapi/sound/asequencer.h @@ -455,6 +455,12 @@ struct snd_seq_remove_events { #define SNDRV_SEQ_PORT_FLG_TIMESTAMP (1<<1) #define SNDRV_SEQ_PORT_FLG_TIME_REAL (1<<2) +/* port direction */ +#define SNDRV_SEQ_PORT_DIR_UNKNOWN 0 +#define SNDRV_SEQ_PORT_DIR_INPUT 1 +#define SNDRV_SEQ_PORT_DIR_OUTPUT 2 +#define SNDRV_SEQ_PORT_DIR_BIDIRECTION 3 + struct snd_seq_port_info { struct snd_seq_addr addr; /* client/port numbers */ char name[64]; /* port name */ @@ -471,7 +477,8 @@ struct snd_seq_port_info { void *kernel; /* reserved for kernel use (must be NULL) */ unsigned int flags; /* misc. conditioning */ unsigned char time_queue; /* queue # for timestamping */ - char reserved[59]; /* for future use */ + unsigned char direction; /* port usage direction (r/w/bidir) */ + char reserved[58]; /* for future use */ }; -- cgit v1.2.3