ALSA: emu10k1: remove pointless locks from timer code
authorOswald Buddenhagen <oswald.buddenhagen@gmx.de>
Fri, 28 Apr 2023 09:59:36 +0000 (11:59 +0200)
committerTakashi Iwai <tiwai@suse.de>
Mon, 8 May 2023 07:20:48 +0000 (09:20 +0200)
Contrary to its name, reg_lock locks the emu data structure, not the
registers. As the functions access only data which is set once at card
initialization, there is no point in locking it.

Actually locking the registers would be pointless as well, as
snd_emu10k1_intr_{en,dis}able() does its own locking, and TIMER is
accessed only in this one place.

Locking snd_emu10k1_timer_{start,stop}() against each other also
wouldn't buy us anything; the functions interleaving their I/O accesses
wouldn't introduce new problems.

Signed-off-by: Oswald Buddenhagen <oswald.buddenhagen@gmx.de>
Link: https://lore.kernel.org/r/20230428095941.1706278-2-oswald.buddenhagen@gmx.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
sound/pci/emu10k1/timer.c

index 2435d3b..993663f 100644 (file)
 static int snd_emu10k1_timer_start(struct snd_timer *timer)
 {
        struct snd_emu10k1 *emu;
-       unsigned long flags;
        unsigned int delay;
 
        emu = snd_timer_chip(timer);
        delay = timer->sticks - 1;
        if (delay < 5 ) /* minimum time is 5 ticks */
                delay = 5;
-       spin_lock_irqsave(&emu->reg_lock, flags);
        snd_emu10k1_intr_enable(emu, INTE_INTERVALTIMERENB);
        outw(delay & TIMER_RATE_MASK, emu->port + TIMER);
-       spin_unlock_irqrestore(&emu->reg_lock, flags);
        return 0;
 }
 
 static int snd_emu10k1_timer_stop(struct snd_timer *timer)
 {
        struct snd_emu10k1 *emu;
-       unsigned long flags;
 
        emu = snd_timer_chip(timer);
-       spin_lock_irqsave(&emu->reg_lock, flags);
        snd_emu10k1_intr_disable(emu, INTE_INTERVALTIMERENB);
-       spin_unlock_irqrestore(&emu->reg_lock, flags);
        return 0;
 }