[alsa-devel] Why use spin_lock or spin_lock_irq in trigger callback (audio capture)?

Hi,

I looked at some PCI audio capture driver like BT878 (sound/pci/bt87x.c) or SAA7134 (drivers/media/video/saa7134-alsa.c), I found that spin_lock instead of spin_lock_irq (or spin_lock_irqsave) is used in trigger function. Is there any reason for that?

Thanks, Yiliang