Staging: comedi: add mpc624 driver

/*

    comedi/drivers/mpc624.c

    Hardware driver for a Micro/sys inc. MPC-624 PC/104 board

    COMEDI - Linux Control and Measurement Device Interface

    Copyright (C) 2000 David A. Schleef <ds@schleef.org>

    This program is free software; you can redistribute it and/or modify

    it under the terms of the GNU General Public License as published by

    the Free Software Foundation; either version 2 of the License, or

    (at your option) any later version.

    This program is distributed in the hope that it will be useful,

    but WITHOUT ANY WARRANTY; without even the implied warranty of

    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License

    along with this program; if not, write to the Free Software

    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

*/

/*

Driver: mpc624

Description: Micro/sys MPC-624 PC/104 board

Devices: [Micro/sys] MPC-624 (mpc624)

Author: Stanislaw Raczynski <sraczynski@op.pl>

Updated: Thu, 15 Sep 2005 12:01:18 +0200

Status: working

    The Micro/sys MPC-624 board is based on the LTC2440 24-bit sigma-delta

    ADC chip.

    Subdevices supported by the driver:

    - Analog In:   supported

    - Digital I/O: not supported

    - LEDs:        not supported

    - EEPROM:      not supported

Configuration Options:

  [0] - I/O base address

  [1] - convertion rate

            Convertion rate  RMS noise  Effective Number Of Bits

         0      3.52kHz        23uV                17

         1      1.76kHz       3.5uV                20

         2       880Hz         2uV                21.3

         3       440Hz        1.4uV               21.8

         4       220Hz         1uV                22.4

         5       110Hz        750uV               22.9

         6       55Hz         510nV               23.4

         7      27.5Hz        375nV                24

         8      13.75Hz       250nV               24.4

         9      6.875Hz       200nV               24.6

   [2] - voltage range

         0      -1.01V .. +1.01V

         1      -10.1V .. +10.1V

*/

#include "../comedidev.h"

#include <linux/ioport.h>

#include <linux/delay.h>

// Consecutive I/O port addresses

#define MPC624_SIZE             16

// Offsets of different ports

#define MPC624_MASTER_CONTROL	0	// not used

#define MPC624_GNMUXCH          1	// Gain, Mux, Channel of ADC

#define MPC624_ADC              2	// read/write to/from ADC

#define MPC624_EE               3	// read/write to/from serial EEPROM via I2C

#define MPC624_LEDS             4	// write to LEDs

#define MPC624_DIO              5	// read/write to/from digital I/O ports

#define MPC624_IRQ_MASK         6	// IRQ masking enable/disable

// Register bits' names

#define MPC624_ADBUSY           (1<<5)

#define MPC624_ADSDO            (1<<4)

#define MPC624_ADFO             (1<<3)

#define MPC624_ADCS             (1<<2)

#define MPC624_ADSCK            (1<<1)

#define MPC624_ADSDI            (1<<0)

// SDI Speed/Resolution Programming bits

#define MPC624_OSR4             (1<<31)

#define MPC624_OSR3             (1<<30)

#define MPC624_OSR2             (1<<29)

#define MPC624_OSR1             (1<<28)

#define MPC624_OSR0             (1<<27)

// 32-bit output value bits' names

#define MPC624_EOC_BIT          (1<<31)

#define MPC624_DMY_BIT          (1<<30)

#define MPC624_SGN_BIT          (1<<29)

// Convertion speeds

/* OSR4 OSR3 OSR2 OSR1 OSR0  Convertion rate  RMS noise  ENOB^

 *  X    0    0    0    1        3.52kHz        23uV      17

 *  X    0    0    1    0        1.76kHz       3.5uV      20

 *  X    0    0    1    1         880Hz         2uV      21.3

 *  X    0    1    0    0         440Hz        1.4uV     21.8

 *  X    0    1    0    1         220Hz         1uV      22.4

 *  X    0    1    1    0         110Hz        750uV     22.9

 *  X    0    1    1    1          55Hz        510nV     23.4

 *  X    1    0    0    0         27.5Hz       375nV      24

 *  X    1    0    0    1        13.75Hz       250nV     24.4

 *  X    1    1    1    1        6.875Hz       200nV     24.6

 *

 * ^ - Effective Number Of Bits

 */

#define MPC624_SPEED_3_52_kHz   (MPC624_OSR4                                           | MPC624_OSR0)

#define MPC624_SPEED_1_76_kHz   (MPC624_OSR4                             | MPC624_OSR1              )

#define MPC624_SPEED_880_Hz     (MPC624_OSR4                             | MPC624_OSR1 | MPC624_OSR0)

#define MPC624_SPEED_440_Hz     (MPC624_OSR4               | MPC624_OSR2                            )

#define MPC624_SPEED_220_Hz     (MPC624_OSR4               | MPC624_OSR2               | MPC624_OSR0)

#define MPC624_SPEED_110_Hz     (MPC624_OSR4               | MPC624_OSR2 | MPC624_OSR1              )

#define MPC624_SPEED_55_Hz      (MPC624_OSR4               | MPC624_OSR2 | MPC624_OSR1 | MPC624_OSR0)

#define MPC624_SPEED_27_5_Hz    (MPC624_OSR4 | MPC624_OSR3                                          )

#define MPC624_SPEED_13_75_Hz   (MPC624_OSR4 | MPC624_OSR3                             | MPC624_OSR0)

#define MPC624_SPEED_6_875_Hz   (MPC624_OSR4 | MPC624_OSR3 | MPC624_OSR2 | MPC624_OSR1 | MPC624_OSR0)

//----------------------------------------------------------------------------

typedef struct {

	unsigned long int ulConvertionRate;	// set by mpc624_attach() from driver's parameters

} skel_private;

#define devpriv ((skel_private *)dev->private)

//----------------------------------------------------------------------------

static const comedi_lrange range_mpc624_bipolar1 = {

	1,

	{

//    BIP_RANGE(1.01) // this is correct,

			// but my MPC-624 actually seems to have a range of 2.02

			BIP_RANGE(2.02)

		}

};

static const comedi_lrange range_mpc624_bipolar10 = {

	1,

	{

//    BIP_RANGE(10.1) // this is correct,

			// but my MPC-624 actually seems to have a range of 20.2

			BIP_RANGE(20.2)

		}

};

//----------------------------------------------------------------------------

static int mpc624_attach(comedi_device * dev, comedi_devconfig * it);

static int mpc624_detach(comedi_device * dev);

//----------------------------------------------------------------------------

static comedi_driver driver_mpc624 = {

      driver_name:"mpc624",

      module:THIS_MODULE,

      attach:mpc624_attach,

      detach:mpc624_detach

};

//----------------------------------------------------------------------------

static int mpc624_ai_rinsn(comedi_device * dev, comedi_subdevice * s,

	comedi_insn * insn, lsampl_t * data);

//----------------------------------------------------------------------------

static int mpc624_attach(comedi_device * dev, comedi_devconfig * it)

{

	comedi_subdevice *s;

	unsigned long iobase;

	iobase = it->options[0];

	rt_printk("comedi%d: mpc624 [0x%04lx, ", dev->minor, iobase);

	if (request_region(iobase, MPC624_SIZE, "mpc624") == NULL) {

		rt_printk("I/O port(s) in use\n");

		return -EIO;

	}

	dev->iobase = iobase;

	dev->board_name = "mpc624";

	// Private structure initialization

	if (alloc_private(dev, sizeof(skel_private)) < 0)

		return -ENOMEM;

	switch (it->options[1]) {

	case 0:

		devpriv->ulConvertionRate = MPC624_SPEED_3_52_kHz;

		rt_printk("3.52 kHz, ");

		break;

	case 1:

		devpriv->ulConvertionRate = MPC624_SPEED_1_76_kHz;

		rt_printk("1.76 kHz, ");

		break;

	case 2:

		devpriv->ulConvertionRate = MPC624_SPEED_880_Hz;

		rt_printk("880 Hz, ");

		break;

	case 3:

		devpriv->ulConvertionRate = MPC624_SPEED_440_Hz;

		rt_printk("440 Hz, ");

		break;

	case 4:

		devpriv->ulConvertionRate = MPC624_SPEED_220_Hz;

		rt_printk("220 Hz, ");

		break;

	case 5:

		devpriv->ulConvertionRate = MPC624_SPEED_110_Hz;

		rt_printk("110 Hz, ");

		break;

	case 6:

		devpriv->ulConvertionRate = MPC624_SPEED_55_Hz;

		rt_printk("55 Hz, ");

		break;

	case 7:

		devpriv->ulConvertionRate = MPC624_SPEED_27_5_Hz;

		rt_printk("27.5 Hz, ");

		break;

	case 8:

		devpriv->ulConvertionRate = MPC624_SPEED_13_75_Hz;

		rt_printk("13.75 Hz, ");

		break;

	case 9:

		devpriv->ulConvertionRate = MPC624_SPEED_6_875_Hz;

		rt_printk("6.875 Hz, ");

		break;

	default:

		rt_printk

			("illegal convertion rate setting! Valid numbers are 0..9. Using 9 => 6.875 Hz, ");

		devpriv->ulConvertionRate = MPC624_SPEED_3_52_kHz;

	}

	// Subdevices structures

	if (alloc_subdevices(dev, 1) < 0)

		return -ENOMEM;

	s = dev->subdevices + 0;

	s->type = COMEDI_SUBD_AI;

	s->subdev_flags = SDF_READABLE | SDF_DIFF;

	s->n_chan = 8;

	switch (it->options[1]) {

	default:

		s->maxdata = 0x3FFFFFFF;

		rt_printk("30 bit, ");

	}

	switch (it->options[1]) {

	case 0:

		s->range_table = &range_mpc624_bipolar1;

		rt_printk("1.01V]: ");

		break;

	default:

		s->range_table = &range_mpc624_bipolar10;

		rt_printk("10.1V]: ");

	}

	s->len_chanlist = 1;

	s->insn_read = mpc624_ai_rinsn;

	rt_printk("attached\n");

	return 1;

}

static int mpc624_detach(comedi_device * dev)

{

	rt_printk("comedi%d: mpc624: remove\n", dev->minor);

	if (dev->iobase)

		release_region(dev->iobase, MPC624_SIZE);

	return 0;

}

// Timeout 200ms

#define TIMEOUT 200

static int mpc624_ai_rinsn(comedi_device * dev, comedi_subdevice * s,

	comedi_insn * insn, lsampl_t * data)

{

	int n, i;

	unsigned long int data_in, data_out;

	unsigned char ucPort;

	// WARNING: We always write 0 to GNSWA bit, so the channel range is +-/10.1Vdc

	outb(insn->chanspec, dev->iobase + MPC624_GNMUXCH);

//    rt_printk("Channel %d: \n", insn->chanspec);

	if (!insn->n) {

		rt_printk("MPC624: Warning, no data to aquire\n");

		return 0;

	}

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

		// Trigger the convertion

		outb(MPC624_ADSCK, dev->iobase + MPC624_ADC);

		comedi_udelay(1);

		outb(MPC624_ADCS | MPC624_ADSCK, dev->iobase + MPC624_ADC);

		comedi_udelay(1);

		outb(0, dev->iobase + MPC624_ADC);

		comedi_udelay(1);

		// Wait for the convertion to end

		for (i = 0; i < TIMEOUT; i++) {

			ucPort = inb(dev->iobase + MPC624_ADC);

			if (ucPort & MPC624_ADBUSY)

				comedi_udelay(1000);

			else

				break;

		}

		if (i == TIMEOUT) {

			rt_printk("MPC624: timeout (%dms)\n", TIMEOUT);

			data[n] = 0;

			return -ETIMEDOUT;

		}

		// Start reading data

		data_in = 0;

		data_out = devpriv->ulConvertionRate;

		comedi_udelay(1);

		for (i = 0; i < 32; i++) {

			// Set the clock low

			outb(0, dev->iobase + MPC624_ADC);

			comedi_udelay(1);

			if (data_out & (1 << 31))	// the next bit is a 1

			{

				// Set the ADSDI line (send to MPC624)

				outb(MPC624_ADSDI, dev->iobase + MPC624_ADC);

				comedi_udelay(1);

				// Set the clock high

				outb(MPC624_ADSCK | MPC624_ADSDI,

					dev->iobase + MPC624_ADC);

			} else	// the next bit is a 0

			{

				// Set the ADSDI line (send to MPC624)

				outb(0, dev->iobase + MPC624_ADC);

				comedi_udelay(1);

				// Set the clock high

				outb(MPC624_ADSCK, dev->iobase + MPC624_ADC);

			}

			// Read ADSDO on high clock (receive from MPC624)

			comedi_udelay(1);

			data_in <<= 1;

			data_in |=

				(inb(dev->iobase +

					MPC624_ADC) & MPC624_ADSDO) >> 4;

			comedi_udelay(1);

			data_out <<= 1;

		}

		// Received 32-bit long value consist of:

		//   31: EOC (End Of Transmission) bit - should be 0

		//   30: DMY (Dummy) bit               - should be 0

		//   29: SIG (Sign) bit                - 1 if the voltage is positive, 0 if negative

		//   28: MSB (Most Significant Bit)    - the first bit of convertion result

		//   ....

		//   05: LSB (Least Significant Bit)   - the last bit of convertion result

		//   04: sub-LSB                       - sub-LSBs are basically noise, but when

		//   03: sub-LSB                         averaged properly, they can increase convertion

		//   02: sub-LSB                         precision up to 29 bits; they can be discarded

		//   01: sub-LSB                         without loss of resolution.

		//   00: sub-LSB

		if (data_in & MPC624_EOC_BIT)

			rt_printk("MPC624: EOC bit is set (data_in=%lu)!",

				data_in);

		if (data_in & MPC624_DMY_BIT)

			rt_printk("MPC624: DMY bit is set (data_in=%lu)!",

				data_in);

		if (data_in & MPC624_SGN_BIT)	// check the sign bit

		{		// The voltage is positive

			data_in &= 0x3FFFFFFF;	// EOC and DMY should be 0, but we will mask them out just to be sure

			data[n] = data_in;	// comedi operates on unsigned numbers, so we don't clear the SGN bit

			// SGN bit is still set! It's correct, since we're converting to unsigned.

		} else {	// The voltage is negative

			// data_in contains a number in 30-bit two's complement code and we must deal with it

			data_in |= MPC624_SGN_BIT;

			data_in = ~data_in;

			data_in += 1;

			data_in &= ~(MPC624_EOC_BIT | MPC624_DMY_BIT);

			// clear EOC and DMY bits

			data_in = 0x20000000 - data_in;

			data[n] = data_in;

		}

	}

	// Return the number of samples read/written

	return n;

}

COMEDI_INITCLEANUP(driver_mpc624);