Commit b047d9cc authored by H Hartley Sweeten's avatar H Hartley Sweeten Committed by Greg Kroah-Hartman
Browse files

staging: comedi: me4000: introduce me4000_ai_reset() 



Introduce a helper function to stop any ai conversions and reset the
ai control register. This consolidates the common code in me4000_reset()
and me4000_ai_cancel().

Use the new helper in the ai (*insn_read) to ensure that the ai control
register is set to a known state after reading the samples.

The ai control register will now always be '0' after the (*cancel) of
a command or doing an (*insn_read). Knowing this the programming of
the register for single acquisition mode in the (*insn_read) can be
simplified.

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 a31b50ed

drivers/staging/comedi/drivers/me4000.c

+23 −33
Original line number Diff line number Diff line
@@ -393,6 +393,19 @@ static int me4000_xilinx_download(struct comedi_device *dev, 
	return 0;

}



static void me4000_ai_reset(struct comedi_device *dev)

{

	unsigned int ctrl;



	/* Stop any running conversion */

	ctrl = inl(dev->iobase + ME4000_AI_CTRL_REG);

	ctrl |= ME4000_AI_CTRL_STOP | ME4000_AI_CTRL_IMMEDIATE_STOP;

	outl(ctrl, dev->iobase + ME4000_AI_CTRL_REG);



	/* Clear the control register */

	outl(0x0, dev->iobase + ME4000_AI_CTRL_REG);

}



static void me4000_reset(struct comedi_device *dev)

{

	struct me4000_private *devpriv = dev->private;
@@ -410,12 +423,7 @@ static void me4000_reset(struct comedi_device *dev) 
	for (chan = 0; chan < 4; chan++)

		outl(0x8000, dev->iobase + ME4000_AO_SINGLE_REG(chan));



	/* Set both stop bits in the analog input control register */

	outl(ME4000_AI_CTRL_IMMEDIATE_STOP | ME4000_AI_CTRL_STOP,

	     dev->iobase + ME4000_AI_CTRL_REG);



	/* Clear the analog input control register */

	outl(0x0, dev->iobase + ME4000_AI_CTRL_REG);

	me4000_ai_reset(dev);



	/* Set both stop bits in the analog output control register */

	val = ME4000_AO_CTRL_IMMEDIATE_STOP | ME4000_AO_CTRL_STOP;
@@ -461,8 +469,7 @@ static int me4000_ai_insn_read(struct comedi_device *dev, 
	unsigned int range = CR_RANGE(insn->chanspec);

	unsigned int aref = CR_AREF(insn->chanspec);

	unsigned int entry;

	unsigned int tmp;

	int ret;

	int ret = 0;

	int i;



	entry = chan | ME4000_AI_LIST_RANGE(range);
@@ -489,20 +496,9 @@ static int me4000_ai_insn_read(struct comedi_device *dev, 


	entry |= ME4000_AI_LIST_LAST_ENTRY;



	/* Clear channel list, data fifo and both stop bits */

	tmp = inl(dev->iobase + ME4000_AI_CTRL_REG);

	tmp &= ~(ME4000_AI_CTRL_CHANNEL_FIFO | ME4000_AI_CTRL_DATA_FIFO |

		 ME4000_AI_CTRL_STOP | ME4000_AI_CTRL_IMMEDIATE_STOP);

	outl(tmp, dev->iobase + ME4000_AI_CTRL_REG);



	/* Set the acquisition mode to single */

	tmp &= ~(ME4000_AI_CTRL_MODE_0 | ME4000_AI_CTRL_MODE_1 |

		 ME4000_AI_CTRL_MODE_2);

	outl(tmp, dev->iobase + ME4000_AI_CTRL_REG);



	/* Enable channel list and data fifo */

	tmp |= ME4000_AI_CTRL_CHANNEL_FIFO | ME4000_AI_CTRL_DATA_FIFO;

	outl(tmp, dev->iobase + ME4000_AI_CTRL_REG);

	/* Enable channel list and data fifo for single acquisition mode */

	outl(ME4000_AI_CTRL_CHANNEL_FIFO | ME4000_AI_CTRL_DATA_FIFO,

	     dev->iobase + ME4000_AI_CTRL_REG);



	/* Generate channel list entry */

	outl(entry, dev->iobase + ME4000_AI_CHANNEL_LIST_REG);
@@ -519,28 +515,22 @@ static int me4000_ai_insn_read(struct comedi_device *dev, 


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

		if (ret)

			return ret;

			break;



		/* 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 insn->n;

	me4000_ai_reset(dev);



	return ret ? ret : insn->n;

}



static int me4000_ai_cancel(struct comedi_device *dev,

			    struct comedi_subdevice *s)

{

	unsigned int ctrl;



	/* Stop any running conversion */

	ctrl = inl(dev->iobase + ME4000_AI_CTRL_REG);

	ctrl |= ME4000_AI_CTRL_STOP | ME4000_AI_CTRL_IMMEDIATE_STOP;

	outl(ctrl, dev->iobase + ME4000_AI_CTRL_REG);



	/* Clear the control register */

	outl(0x0, dev->iobase + ME4000_AI_CTRL_REG);

	me4000_ai_reset(dev);



	return 0;

}

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