/*
    comedi/drivers/adq12b.c
    driver for MicroAxial ADQ12-B data acquisition and control card

    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: adq12b
Description: driver for MicroAxial ADQ12-B data acquisition and control card
Devices: [MicroAxial] ADQ12-B (adq12b)
Author: jeremy theler <thelerg@ib.cnea.gov.ar>
Updated: Thu, 21 Feb 2008 02:56:27 -0300
Status: works

Driver for the acquisition card ADQ12-B (without any add-on).

 - Analog input is subdevice 0 (16 channels single-ended or 8 differential)
 - Digital input is subdevice 1 (5 channels)
 - Digital output is subdevice 1 (8 channels)
 - The PACER is not supported in this version

If you do not specify any options, they will default to

  # comedi_config /dev/comedi0 adq12b 0x300,0,0

  option 1: I/O base address. The following table is provided as a help
   of the hardware jumpers.

	 address            jumper JADR
	  0x300                 1 (factory default)
	  0x320                 2
	  0x340                 3
	  0x360                 4
	  0x380                 5
	  0x3A0                 6

  option 2: unipolar/bipolar ADC selection: 0 -> bipolar, 1 -> unipolar

	selection         comedi_config option            JUB
	 bipolar                0                         2-3 (factory default)
	 unipolar               1                         1-2

  option 3: single-ended/differential AI selection: 0 -> SE, 1 -> differential

	selection         comedi_config option     JCHA    JCHB
       single-ended             0                  1-2     1-2 (factory default)
       differential             1                  2-3     2-3

   written by jeremy theler <thelerg@ib.cnea.gov.ar>

   instituto balseiro
   comision nacional de energia atomica
   universidad nacional de cuyo
   argentina

   21-feb-2008
     + changed supported devices string (missused the [] and ())

   13-oct-2007
     + first try


*/

#include "../comedidev.h"

/* address scheme (page 2.17 of the manual) */
#define ADQ12B_SIZE     16

#define ADQ12B_CTREG    0x00
#define ADQ12B_STINR    0x00
#define ADQ12B_OUTBR    0x04
#define ADQ12B_ADLOW    0x08
#define ADQ12B_ADHIG    0x09
#define ADQ12B_CONT0    0x0c
#define ADQ12B_CONT1    0x0d
#define ADQ12B_CONT2    0x0e
#define ADQ12B_COWORD   0x0f

/* mask of the bit at STINR to check end of conversion */
#define ADQ12B_EOC     0x20

#define TIMEOUT        20

/* available ranges through the PGA gains */
static const struct comedi_lrange range_adq12b_ai_bipolar = { 4, {
								  BIP_RANGE(5),
								  BIP_RANGE(2),
								  BIP_RANGE(1),
								  BIP_RANGE(0.5)
								  }
};

static const struct comedi_lrange range_adq12b_ai_unipolar = { 4, {
								   UNI_RANGE(5),
								   UNI_RANGE(2),
								   UNI_RANGE(1),
								   UNI_RANGE
								   (0.5)
								   }
};

struct adq12b_board {
	const char *name;
	int ai_se_chans;
	int ai_diff_chans;
	int ai_bits;
	int di_chans;
	int do_chans;
};

static const struct adq12b_board adq12b_boards[] = {
	{
	 .name = "adq12b",
	 .ai_se_chans = 16,
	 .ai_diff_chans = 8,
	 .ai_bits = 12,
	 .di_chans = 5,
	 .do_chans = 8}
/* potentially, more adq-based deviced will be added */
/*,
	.name = "adq12b",
	.ai_chans = 16,  // this is just for reference, hardcoded again later
	.ai_bits = 12,
	.di_chans = 8,
	.do_chans = 5
	}*/
};

#define thisboard ((const struct adq12b_board *)dev->board_ptr)

struct adq12b_private {
	int unipolar;		/* option 2 of comedi_config (1 is iobase) */
	int differential;	/* option 3 of comedi_config */
	int last_channel;
	int last_range;
	unsigned int digital_state;
};

#define devpriv ((struct adq12b_private *)dev->private)

/*
 * The struct comedi_driver structure tells the Comedi core module
 * which functions to call to configure/deconfigure (attach/detach)
 * the board, and also about the kernel module that contains
 * the device code.
 */
static int adq12b_attach(struct comedi_device *dev,
			 struct comedi_devconfig *it);
static int adq12b_detach(struct comedi_device *dev);

static struct comedi_driver driver_adq12b = {
	.driver_name = "adq12b",
	.module = THIS_MODULE,
	.attach = adq12b_attach,
	.detach = adq12b_detach,
	.board_name = &adq12b_boards[0].name,
	.offset = sizeof(struct adq12b_board),
	.num_names = ARRAY_SIZE(adq12b_boards),
};

static int adq12b_ai_rinsn(struct comedi_device *dev,
			   struct comedi_subdevice *s, struct comedi_insn *insn,
			   unsigned int *data);
static int adq12b_di_insn_bits(struct comedi_device *dev,
			       struct comedi_subdevice *s,
			       struct comedi_insn *insn, unsigned int *data);
static int adq12b_do_insn_bits(struct comedi_device *dev,
			       struct comedi_subdevice *s,
			       struct comedi_insn *insn, unsigned int *data);

/*
 * Attach is called by the Comedi core to configure the driver
 * for a particular board.  If you specified a board_name array
 * in the driver structure, dev->board_ptr contains that
 * address.
 */
static int adq12b_attach(struct comedi_device *dev, struct comedi_devconfig *it)
{
	struct comedi_subdevice *s;
	unsigned long iobase;
	int unipolar, differential;

	iobase = it->options[0];
	unipolar = it->options[1];
	differential = it->options[2];

	printk(KERN_INFO "comedi%d: adq12b called with options base=0x%03lx, "
	       "%s and %s\n", dev->minor, iobase,
	       (unipolar == 1) ? "unipolar" : "bipolar",
	       (differential == 1) ? "differential" : "single-ended");

	/* if no address was specified, try the default 0x300 */
	if (iobase == 0) {
		printk(KERN_WARNING "comedi%d: adq12b warning: I/O base "
		       "address not specified. Trying the default 0x300.\n",
		       dev->minor);
		iobase = 0x300;
	}

	printk("comedi%d: adq12b: 0x%04lx ", dev->minor, iobase);
	if (!request_region(iobase, ADQ12B_SIZE, "adq12b")) {
		printk("I/O port conflict\n");
		return -EIO;
	}
	dev->iobase = iobase;

/*
 * Initialize dev->board_name.  Note that we can use the "thisboard"
 * macro now, since we just initialized it in the last line.
 */
	dev->board_name = thisboard->name;

/*
 * Allocate the private structure area.  alloc_private() is a
 * convenient macro defined in comedidev.h.
 */
	if (alloc_private(dev, sizeof(struct adq12b_private)) < 0)
		return -ENOMEM;

/* fill in devpriv structure */
	devpriv->unipolar = unipolar;
	devpriv->differential = differential;
	devpriv->digital_state = 0;
/* initialize channel and range to -1 so we make sure we always write
   at least once to the CTREG in the instruction */
	devpriv->last_channel = -1;
	devpriv->last_range = -1;

/*
 * Allocate the subdevice structures.  alloc_subdevice() is a
 * convenient macro defined in comedidev.h.
 */
	if (alloc_subdevices(dev, 3) < 0)
		return -ENOMEM;

	s = dev->subdevices + 0;
	/* analog input subdevice */
	s->type = COMEDI_SUBD_AI;
	if (differential) {
		s->subdev_flags = SDF_READABLE | SDF_GROUND | SDF_DIFF;
		s->n_chan = thisboard->ai_diff_chans;
	} else {
		s->subdev_flags = SDF_READABLE | SDF_GROUND;
		s->n_chan = thisboard->ai_se_chans;
	}

	if (unipolar)
		s->range_table = &range_adq12b_ai_unipolar;
	else
		s->range_table = &range_adq12b_ai_bipolar;

	s->maxdata = (1 << thisboard->ai_bits) - 1;

	s->len_chanlist = 4;	/* This is the maximum chanlist length that
				   the board can handle */
	s->insn_read = adq12b_ai_rinsn;

	s = dev->subdevices + 1;
	/* digital input subdevice */
	s->type = COMEDI_SUBD_DI;
	s->subdev_flags = SDF_READABLE;
	s->n_chan = thisboard->di_chans;
	s->maxdata = 1;
	s->range_table = &range_digital;
	s->insn_bits = adq12b_di_insn_bits;

	s = dev->subdevices + 2;
	/* digital output subdevice */
	s->type = COMEDI_SUBD_DO;
	s->subdev_flags = SDF_WRITABLE;
	s->n_chan = thisboard->do_chans;
	s->maxdata = 1;
	s->range_table = &range_digital;
	s->insn_bits = adq12b_do_insn_bits;

	printk(KERN_INFO "attached\n");

	return 0;
}

/*
 * _detach is called to deconfigure a device.  It should deallocate
 * resources.
 * This function is also called when _attach() fails, so it should be
 * careful not to release resources that were not necessarily
 * allocated by _attach().  dev->private and dev->subdevices are
 * deallocated automatically by the core.
 */
static int adq12b_detach(struct comedi_device *dev)
{
	if (dev->iobase)
		release_region(dev->iobase, ADQ12B_SIZE);

	kfree(devpriv);

	printk(KERN_INFO "comedi%d: adq12b: removed\n", dev->minor);

	return 0;
}

/*
 * "instructions" read/write data in "one-shot" or "software-triggered"
 * mode.
 */

static int adq12b_ai_rinsn(struct comedi_device *dev,
			   struct comedi_subdevice *s, struct comedi_insn *insn,
			   unsigned int *data)
{
	int n, i;
	int range, channel;
	unsigned char hi, lo, status;

	/* change channel and range only if it is different from the previous */
	range = CR_RANGE(insn->chanspec);
	channel = CR_CHAN(insn->chanspec);
	if (channel != devpriv->last_channel || range != devpriv->last_range) {
		outb((range << 4) | channel, dev->iobase + ADQ12B_CTREG);
		udelay(50);	/* wait for the mux to settle */
	}

	/* trigger conversion */
	status = inb(dev->iobase + ADQ12B_ADLOW);

	/* convert n samples */
	for (n = 0; n < insn->n; n++) {

		/* wait for end of convertion */
		i = 0;
		do {
			/* udelay(1); */
			status = inb(dev->iobase + ADQ12B_STINR);
			status = status & ADQ12B_EOC;
		} while (status == 0 && ++i < TIMEOUT);
		/* } while (++i < 10); */

		/* read data */
		hi = inb(dev->iobase + ADQ12B_ADHIG);
		lo = inb(dev->iobase + ADQ12B_ADLOW);

		/* printk("debug: chan=%d range=%d status=%d hi=%d lo=%d\n",
		       channel, range, status,  hi, lo); */
		data[n] = (hi << 8) | lo;

	}

	/* return the number of samples read/written */
	return n;
}

static int adq12b_di_insn_bits(struct comedi_device *dev,
			       struct comedi_subdevice *s,
			       struct comedi_insn *insn, unsigned int *data)
{

	/* only bits 0-4 have information about digital inputs */
	data[1] = (inb(dev->iobase + ADQ12B_STINR) & (0x1f));

	return 2;
}

static int adq12b_do_insn_bits(struct comedi_device *dev,
			       struct comedi_subdevice *s,
			       struct comedi_insn *insn, unsigned int *data)
{
	int channel;

	for (channel = 0; channel < 8; channel++)
		if (((data[0] >> channel) & 0x01) != 0)
			outb((((data[1] >> channel) & 0x01) << 3) | channel,
			     dev->iobase + ADQ12B_OUTBR);

	/* store information to retrieve when asked for reading */
	if (data[0]) {
		devpriv->digital_state &= ~data[0];
		devpriv->digital_state |= (data[0] & data[1]);
	}

	data[1] = devpriv->digital_state;

	return 2;
}

/*
 * A convenient macro that defines init_module() and cleanup_module(),
 * as necessary.
 */
COMEDI_INITCLEANUP(driver_adq12b);