Commit fb7891e4 authored by H Hartley Sweeten's avatar H Hartley Sweeten Committed by Greg Kroah-Hartman
Browse files

staging: comedi: me4000: fix me4000_ai_insn_read() 



The coemdi (*insn_read) functions are supposed to read insn->n values
from the hardware. Make this function work like the core expects.

Use the comedi_offset_munge() helper to munge the two's complement
values to offset binary.

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 023c129f

drivers/staging/comedi/drivers/me4000.c

+14 −18
Original line number Diff line number Diff line
@@ -456,16 +456,8 @@ static int me4000_ai_insn_read(struct comedi_device *dev, 
	int aref = CR_AREF(insn->chanspec);

	unsigned int entry = 0;

	unsigned int tmp;

	unsigned int lval;

	int ret;



	if (insn->n == 0) {

		return 0;

	} else if (insn->n > 1) {

		dev_err(dev->class_dev, "Invalid instruction length %d\n",

			insn->n);

		return -EINVAL;

	}

	int i;



	entry |= ME4000_AI_LIST_RANGE(rang);

	entry |= chan;
@@ -515,18 +507,22 @@ static int me4000_ai_insn_read(struct comedi_device *dev, 
	outl(ME4000_AI_MIN_TICKS, dev->iobase + ME4000_AI_CHAN_TIMER_REG);

	outl(ME4000_AI_MIN_TICKS, dev->iobase + ME4000_AI_CHAN_PRE_TIMER_REG);



	/* Start conversion by dummy read */

	for (i = 0; i < insn->n; i++) {

		unsigned int val;



		/* start conversion by dummy read */

		inl(dev->iobase + ME4000_AI_START_REG);



		ret = comedi_timeout(dev, s, insn, me4000_ai_eoc, 0);

		if (ret)

			return ret;



	/* Read value from data fifo */

	lval = inl(dev->iobase + ME4000_AI_DATA_REG) & 0xFFFF;

	data[0] = lval ^ 0x8000;

		/* read two's complement value and munge to offset binary */

		val = inl(dev->iobase + ME4000_AI_DATA_REG);

		data[i] = comedi_offset_munge(s, val);

	}



	return 1;

	return insn->n;

}



static int me4000_ai_cancel(struct comedi_device *dev,

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