ALSA: opl3: circular locking in the snd_opl3_note_on() and snd_opl3_note_off()

[GitHub/LineageOS/android_kernel_samsung_universal7580.git] / sound / drivers / opl3 / opl3_midi.c

diff --git a/sound/drivers/opl3/opl3_midi.c b/sound/drivers/opl3/opl3_midi.c
index 6e7d09ae0e82310fa053155c43ec2b9c11d1d084..7d722a025d0d7783d775c824a0076b8160b11304 100644 (file)
--- a/sound/drivers/opl3/opl3_midi.c
+++ b/sound/drivers/opl3/opl3_midi.c
@@ -29,6 +29,8 @@ extern char snd_opl3_regmap[MAX_OPL2_VOICES][4];
 
 extern int use_internal_drums;
 
+static void snd_opl3_note_off_unsafe(void *p, int note, int vel,
+                                    struct snd_midi_channel *chan);
 /*
  * The next table looks magical, but it certainly is not. Its values have
  * been calculated as table[i]=8*log(i/64)/log(2) with an obvious exception
@@ -242,16 +244,20 @@ void snd_opl3_timer_func(unsigned long data)
        int again = 0;
        int i;
 
-       spin_lock_irqsave(&opl3->sys_timer_lock, flags);
+       spin_lock_irqsave(&opl3->voice_lock, flags);
        for (i = 0; i < opl3->max_voices; i++) {
                struct snd_opl3_voice *vp = &opl3->voices[i];
                if (vp->state > 0 && vp->note_off_check) {
                        if (vp->note_off == jiffies)
-                               snd_opl3_note_off(opl3, vp->note, 0, vp->chan);
+                               snd_opl3_note_off_unsafe(opl3, vp->note, 0,
+                                                        vp->chan);
                        else
                                again++;
                }
        }
+       spin_unlock_irqrestore(&opl3->voice_lock, flags);
+
+       spin_lock_irqsave(&opl3->sys_timer_lock, flags);
        if (again) {
                opl3->tlist.expires = jiffies + 1;      /* invoke again */
                add_timer(&opl3->tlist);
@@ -658,15 +664,14 @@ static void snd_opl3_kill_voice(struct snd_opl3 *opl3, int voice)
 /*
  * Release a note in response to a midi note off.
  */
-void snd_opl3_note_off(void *p, int note, int vel, struct snd_midi_channel *chan)
+static void snd_opl3_note_off_unsafe(void *p, int note, int vel,
+                                    struct snd_midi_channel *chan)
 {
        struct snd_opl3 *opl3;
 
        int voice;
        struct snd_opl3_voice *vp;
 
-       unsigned long flags;
-
        opl3 = p;
 
 #ifdef DEBUG_MIDI
@@ -674,12 +679,9 @@ void snd_opl3_note_off(void *p, int note, int vel, struct snd_midi_channel *chan
                   chan->number, chan->midi_program, note);
 #endif
 
-       spin_lock_irqsave(&opl3->voice_lock, flags);
-
        if (opl3->synth_mode == SNDRV_OPL3_MODE_SEQ) {
                if (chan->drum_channel && use_internal_drums) {
                        snd_opl3_drum_switch(opl3, note, vel, 0, chan);
-                       spin_unlock_irqrestore(&opl3->voice_lock, flags);
                        return;
                }
                /* this loop will hopefully kill all extra voices, because
@@ -697,6 +699,16 @@ void snd_opl3_note_off(void *p, int note, int vel, struct snd_midi_channel *chan
                        snd_opl3_kill_voice(opl3, voice);
                }
        }
+}
+
+void snd_opl3_note_off(void *p, int note, int vel,
+                      struct snd_midi_channel *chan)
+{
+       struct snd_opl3 *opl3 = p;
+       unsigned long flags;
+
+       spin_lock_irqsave(&opl3->voice_lock, flags);
+       snd_opl3_note_off_unsafe(p, note, vel, chan);
        spin_unlock_irqrestore(&opl3->voice_lock, flags);
 }