UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

ALSA: dice: fix wrong reference count for stream functionality at error path of rawmidi interface 

In IEC 61883-6, several types of sampling data can be multiplexed into
payload of common isochronous packet (CIP). For typical audio and music
units, PCM samples and MIDI messages are multiplexed into one packet
streaming.

ALSA dice driver allows applications of rawmidi interface to start
packet streaming for transmission of MIDI messages. However at error
path, the reference count of stream functionality is not operated
correctly. This can brings a bug that packet streaming is not stopped
when all referrers release the count.

This commit fixes the bug.

Fixes: 3cd2c2d780 ("ALSA: dice: reserve/release isochronous resources in pcm.hw_params/hw_free callbacks")
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Takashi Sakamoto 2019-07-07 14:20:09 +09:00 committed by Takashi Iwai
parent 03a954aef7
commit e79c3f0c00
1 changed files with 2 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
sound/firewire/dice/dice-midi.c
View File

@ -22,6 +22,8 @@ static int midi_open(struct snd_rawmidi_substream *substream)
if (err >= 0) {
++dice->substreams_counter;
err = snd_dice_stream_start_duplex(dice);
if (err < 0)
--dice->substreams_counter;
}
mutex_unlock(&dice->mutex);