Commit 245bd462 authored by H Hartley Sweeten's avatar H Hartley Sweeten Committed by Greg Kroah-Hartman
Browse files

staging: comedi: me4000: simplify analog input range programming 



The comedi_lrange table for the analog inputs is inverted compared
to the values that need to be written to the ME4000_AI_CHANNEL_LIST_REG
to select the range.

Create a macro, ME4000_AI_LIST_RANGE(), to handle the inversion. Remove
the old defines and simplify the code a bit.

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 271f5aa0

drivers/staging/comedi/drivers/me4000.c

+9 −32
Original line number Diff line number Diff line
@@ -111,10 +111,7 @@ broken. 
#define ME4000_AI_CTRL_BIT_EX_TRIG_BOTH		(1 << 31)

#define ME4000_AI_CHANNEL_LIST_REG		0x78

#define ME4000_AI_LIST_INPUT_DIFFERENTIAL	(1 << 5)

#define ME4000_AI_LIST_RANGE_BIPOLAR_10		(0 << 6)

#define ME4000_AI_LIST_RANGE_BIPOLAR_2_5	(1 << 6)

#define ME4000_AI_LIST_RANGE_UNIPOLAR_10	(2 << 6)

#define ME4000_AI_LIST_RANGE_UNIPOLAR_2_5	(3 << 6)

#define ME4000_AI_LIST_RANGE(x)			((3 - ((x) & 3)) << 6)

#define ME4000_AI_LIST_LAST_ENTRY		(1 << 8)

#define ME4000_AI_DATA_REG			0x7c

#define ME4000_AI_CHAN_TIMER_REG		0x80
@@ -301,6 +298,12 @@ static const struct me4000_board me4000_boards[] = { 
	},

};



/*

 * NOTE: the ranges here are inverted compared to the values

 * written to the ME4000_AI_CHANNEL_LIST_REG,

 *

 * The ME4000_AI_LIST_RANGE() macro handles the inversion.

 */

static const struct comedi_lrange me4000_ai_range = {

	4, {

		UNI_RANGE(2.5),
@@ -455,24 +458,7 @@ static int me4000_ai_insn_read(struct comedi_device *dev, 
		return -EINVAL;

	}



	switch (rang) {

	case 0:

		entry |= ME4000_AI_LIST_RANGE_UNIPOLAR_2_5;

		break;

	case 1:

		entry |= ME4000_AI_LIST_RANGE_UNIPOLAR_10;

		break;

	case 2:

		entry |= ME4000_AI_LIST_RANGE_BIPOLAR_2_5;

		break;

	case 3:

		entry |= ME4000_AI_LIST_RANGE_BIPOLAR_10;

		break;

	default:

		dev_err(dev->class_dev, "Invalid range specified\n");

		return -EINVAL;

	}



	entry |= ME4000_AI_LIST_RANGE(rang);

	entry |= chan;

	if (aref == AREF_DIFF) {

		if (!(s->subdev_flags && SDF_DIFF)) {
@@ -680,16 +666,7 @@ static int ai_write_chanlist(struct comedi_device *dev, 
		rang = CR_RANGE(cmd->chanlist[i]);

		aref = CR_AREF(cmd->chanlist[i]);



		entry = chan;



		if (rang == 0)

			entry |= ME4000_AI_LIST_RANGE_UNIPOLAR_2_5;

		else if (rang == 1)

			entry |= ME4000_AI_LIST_RANGE_UNIPOLAR_10;

		else if (rang == 2)

			entry |= ME4000_AI_LIST_RANGE_BIPOLAR_2_5;

		else

			entry |= ME4000_AI_LIST_RANGE_BIPOLAR_10;

		entry = chan | ME4000_AI_LIST_RANGE(rang);



		if (aref == AREF_DIFF)

			entry |= ME4000_AI_LIST_INPUT_DIFFERENTIAL;

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