Commit c3f7e153 authored by H Hartley Sweeten's avatar H Hartley Sweeten Committed by Greg Kroah-Hartman
Browse files

staging: comedi: quatech_daqp_cs: introduce daqp_ai_get_sample() 



Introduce a helper function to get a two's complement sample from
the FIFO and munge it to the offset binary format that comedi uses.

Signed-off-by: default avatarH Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: default avatarIan Abbott <abbotti@mev.co.uk>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 4d6b7008

drivers/staging/comedi/drivers/quatech_daqp_cs.c

+16 −7
Original line number Diff line number Diff line
@@ -172,6 +172,20 @@ static int daqp_ai_cancel(struct comedi_device *dev, struct comedi_subdevice *s) 
	return 0;

}



static unsigned int daqp_ai_get_sample(struct comedi_device *dev,

				       struct comedi_subdevice *s)

{

	unsigned int val;



	/*

	 * Get a two's complement sample from the FIFO and

	 * return the munged offset binary value.

	 */

	val = inb(dev->iobase + DAQP_FIFO);

	val |= inb(dev->iobase + DAQP_FIFO) << 8;

	return comedi_offset_munge(s, val);

}



/* Interrupt handler

 *

 * Operates in one of two modes.  If devpriv->interrupt_mode is
@@ -209,10 +223,7 @@ static enum irqreturn daqp_interrupt(int irq, void *dev_id) 
				break;

			}



			data = inb(dev->iobase + DAQP_FIFO);

			data |= inb(dev->iobase + DAQP_FIFO) << 8;

			data ^= 0x8000;



			data = daqp_ai_get_sample(dev, s);

			comedi_buf_write_samples(s, &data, 1);



			/* If there's a limit, decrement it
@@ -323,9 +334,7 @@ static int daqp_ai_insn_read(struct comedi_device *dev, 
		if (wait_for_completion_interruptible(&devpriv->eos))

			return -EINTR;



		data[i] = inb(dev->iobase + DAQP_FIFO);

		data[i] |= inb(dev->iobase + DAQP_FIFO) << 8;

		data[i] ^= 0x8000;

		data[i] = daqp_ai_get_sample(dev, s);

	}



	return insn->n;