As discussed in [1] the tasklet_disable is not a proper function for teardown.
We need to ensure irq is disabled, followed by ensuring that don't schedule any
more tasklets and then its safe to use tasklet_kill().
Here in at_hdmac driver we use free_irq() before tasklet_kill(). The free_irq()
will ensure that the irq is disabled and also wait till all scheduled interrupts
are executed by invoking synchronize_irq(). So we need to only do tasklet_kill()
after invoking free_irq()
[1]: http://lwn.net/Articles/588457/
Reported-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Vinod Koul <vinod.koul@intel.com>