From 384669921779806105c56751abff41fa0127f93a Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Tue, 14 Jan 2025 11:47:01 +0100 Subject: ALSA: rawmidi: Make tied_device=0 as default / unknown In the original change, rawmidi_info.tied_device showed -1 for the unknown or untied device. But this would require the user-space to check the protocol version and judge the value conditionally, which is rather error-prone. Instead, set the tied_device = 0 to be default as unknown, and indicate the real device with the offset 1, for achieving more backward compatibility. Suggested-by: Jaroslav Kysela Link: https://patch.msgid.link/20250114104711.19197-1-tiwai@suse.de Signed-off-by: Takashi Iwai --- include/sound/rawmidi.h | 9 +++++++++ include/uapi/sound/asound.h | 2 +- 2 files changed, 10 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/sound/rawmidi.h b/include/sound/rawmidi.h index 6f2e95298fc7..6916f7133597 100644 --- a/include/sound/rawmidi.h +++ b/include/sound/rawmidi.h @@ -191,4 +191,13 @@ long snd_rawmidi_kernel_read(struct snd_rawmidi_substream *substream, long snd_rawmidi_kernel_write(struct snd_rawmidi_substream *substream, const unsigned char *buf, long count); +/* set up the tied devices */ +static inline void snd_rawmidi_tie_devices(struct snd_rawmidi *r1, + struct snd_rawmidi *r2) +{ + /* tied_device field keeps the device+1 (so that 0 being unknown) */ + r1->tied_device = r2->device + 1; + r2->tied_device = r1->device + 1; +} + #endif /* __SOUND_RAWMIDI_H */ diff --git a/include/uapi/sound/asound.h b/include/uapi/sound/asound.h index 000b36c0e2b9..5a049eeaecce 100644 --- a/include/uapi/sound/asound.h +++ b/include/uapi/sound/asound.h @@ -730,7 +730,7 @@ enum { #define SNDRV_RAWMIDI_INFO_UMP 0x00000008 #define SNDRV_RAWMIDI_INFO_STREAM_INACTIVE 0x00000010 -#define SNDRV_RAWMIDI_DEVICE_UNKNOWN -1 +#define SNDRV_RAWMIDI_DEVICE_UNKNOWN 0 struct snd_rawmidi_info { unsigned int device; /* RO/WR (control): device number */ -- cgit v1.2.3