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staging: comedi: ni_mio_common: always lock in ni_ai_poll() 

`ni_ai_poll()` currently acquires (and later releases) the comedi
device's spin-lock iff `in_interrupt()` returns 0.  However, it is only
called during processing of a `COMEDI_POLL` ioctl so `in_interrupt()`
will always return 0 in this case.  Remove this test and acquire/release
the spin-lock unconditionally.  This eliminates a sparse warning about
different lock contexts for basic block.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Ian Abbott 2012-09-24 16:27:59 +01:00 committed by Greg Kroah-Hartman
parent affdc230d7
commit 3cd73bc1cf
1 changed files with 3 additions and 5 deletions
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8
drivers/staging/comedi/drivers/ni_mio_common.c
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@ -1766,20 +1766,18 @@ static int ni_ai_reset(struct comedi_device *dev, struct comedi_subdevice *s)
static int ni_ai_poll(struct comedi_device *dev, struct comedi_subdevice *s)
{
unsigned long flags = 0;
unsigned long flags;
int count;
/* lock to avoid race with interrupt handler */
if (in_interrupt() == 0)
spin_lock_irqsave(&dev->spinlock, flags);
spin_lock_irqsave(&dev->spinlock, flags);
#ifndef PCIDMA
ni_handle_fifo_dregs(dev);
#else
ni_sync_ai_dma(dev);
#endif
count = s->async->buf_write_count - s->async->buf_read_count;
if (in_interrupt() == 0)
spin_unlock_irqrestore(&dev->spinlock, flags);
spin_unlock_irqrestore(&dev->spinlock, flags);
return count;
}