/*
 * icp_multi.c
 * Comedi driver for Inova ICP_MULTI board
 *
 * COMEDI - Linux Control and Measurement Device Interface
 * Copyright (C) 1997-2002 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.
 */

/*
 * Driver: icp_multi
 * Description: Inova ICP_MULTI
 * Devices: [Inova] ICP_MULTI (icp_multi)
 * Author: Anne Smorthit <anne.smorthit@sfwte.ch>
 * Status: works
 *
 * Configuration options: not applicable, uses PCI auto config
 *
 * The driver works for analog input and output and digital input and
 * output. It does not work with interrupts or with the counters. Currently
 * no support for DMA.
 *
 * It has 16 single-ended or 8 differential Analogue Input channels with
 * 12-bit resolution.  Ranges : 5V, 10V, +/-5V, +/-10V, 0..20mA and 4..20mA.
 * Input ranges can be individually programmed for each channel.  Voltage or
 * current measurement is selected by jumper.
 *
 * There are 4 x 12-bit Analogue Outputs.  Ranges : 5V, 10V, +/-5V, +/-10V
 *
 * 16 x Digital Inputs, 24V
 *
 * 8 x Digital Outputs, 24V, 1A
 *
 * 4 x 16-bit counters - not implemented
 */

#include <linux/module.h>
#include <linux/delay.h>

#include "../comedi_pci.h"

#define ICP_MULTI_ADC_CSR	0x00	/* R/W: ADC command/status register */
#define ICP_MULTI_ADC_CSR_ST	BIT(0)	/* Start ADC */
#define ICP_MULTI_ADC_CSR_BSY	BIT(0)	/* ADC busy */
#define ICP_MULTI_ADC_CSR_BI	BIT(4)	/* Bipolar input range */
#define ICP_MULTI_ADC_CSR_RA	BIT(5)	/* Input range 0 = 5V, 1 = 10V */
#define ICP_MULTI_ADC_CSR_DI	BIT(6)	/* Input mode 1 = differential */
#define ICP_MULTI_ADC_CSR_DI_CHAN(x) (((x) & 0x7) << 9)
#define ICP_MULTI_ADC_CSR_SE_CHAN(x) (((x) & 0xf) << 8)
#define ICP_MULTI_AI		2	/* R:   Analogue input data */
#define ICP_MULTI_DAC_CSR	0x04	/* R/W: DAC command/status register */
#define ICP_MULTI_DAC_CSR_ST	BIT(0)	/* Start DAC */
#define ICP_MULTI_DAC_CSR_BSY	BIT(0)	/* DAC busy */
#define ICP_MULTI_DAC_CSR_BI	BIT(4)	/* Bipolar output range */
#define ICP_MULTI_DAC_CSR_RA	BIT(5)	/* Output range 0 = 5V, 1 = 10V */
#define ICP_MULTI_DAC_CSR_CHAN(x) (((x) & 0x3) << 8)
#define ICP_MULTI_AO		6	/* R/W: Analogue output data */
#define ICP_MULTI_DI		8	/* R/W: Digital inputs */
#define ICP_MULTI_DO		0x0A	/* R/W: Digital outputs */
#define ICP_MULTI_INT_EN	0x0c	/* R/W: Interrupt enable register */
#define ICP_MULTI_INT_STAT	0x0e	/* R/W: Interrupt status register */
#define ICP_MULTI_INT_ADC_RDY	BIT(0)	/* A/D conversion ready interrupt */
#define ICP_MULTI_INT_DAC_RDY	BIT(1)	/* D/A conversion ready interrupt */
#define ICP_MULTI_INT_DOUT_ERR	BIT(2)	/* Digital output error interrupt */
#define ICP_MULTI_INT_DIN_STAT	BIT(3)	/* Digital input status change int. */
#define ICP_MULTI_INT_CIE0	BIT(4)	/* Counter 0 overrun interrupt */
#define ICP_MULTI_INT_CIE1	BIT(5)	/* Counter 1 overrun interrupt */
#define ICP_MULTI_INT_CIE2	BIT(6)	/* Counter 2 overrun interrupt */
#define ICP_MULTI_INT_CIE3	BIT(7)	/* Counter 3 overrun interrupt */
#define ICP_MULTI_INT_MASK	0xff	/* All interrupts */
#define ICP_MULTI_CNTR0		0x10	/* R/W: Counter 0 */
#define ICP_MULTI_CNTR1		0x12	/* R/W: counter 1 */
#define ICP_MULTI_CNTR2		0x14	/* R/W: Counter 2 */
#define ICP_MULTI_CNTR3		0x16	/* R/W: Counter 3 */

/* analog input and output have the same range options */
static const struct comedi_lrange icp_multi_ranges = {
	4, {
		UNI_RANGE(5),
		UNI_RANGE(10),
		BIP_RANGE(5),
		BIP_RANGE(10)
	}
};

static const char range_codes_analog[] = { 0x00, 0x20, 0x10, 0x30 };

static int icp_multi_ai_eoc(struct comedi_device *dev,
			    struct comedi_subdevice *s,
			    struct comedi_insn *insn,
			    unsigned long context)
{
	unsigned int status;

	status = readw(dev->mmio + ICP_MULTI_ADC_CSR);
	if ((status & ICP_MULTI_ADC_CSR_BSY) == 0)
		return 0;
	return -EBUSY;
}

static int icp_multi_ai_insn_read(struct comedi_device *dev,
				  struct comedi_subdevice *s,
				  struct comedi_insn *insn,
				  unsigned int *data)
{
	unsigned int chan = CR_CHAN(insn->chanspec);
	unsigned int range = CR_RANGE(insn->chanspec);
	unsigned int aref = CR_AREF(insn->chanspec);
	unsigned int adc_csr;
	int ret = 0;
	int n;

	/* Set mode and range data for specified channel */
	if (aref == AREF_DIFF) {
		adc_csr = ICP_MULTI_ADC_CSR_DI_CHAN(chan) |
			  ICP_MULTI_ADC_CSR_DI;
	} else {
		adc_csr = ICP_MULTI_ADC_CSR_SE_CHAN(chan);
	}
	adc_csr |= range_codes_analog[range];
	writew(adc_csr, dev->mmio + ICP_MULTI_ADC_CSR);

	for (n = 0; n < insn->n; n++) {
		/*  Set start ADC bit */
		writew(adc_csr | ICP_MULTI_ADC_CSR_ST,
		       dev->mmio + ICP_MULTI_ADC_CSR);

		udelay(1);

		/*  Wait for conversion to complete, or get fed up waiting */
		ret = comedi_timeout(dev, s, insn, icp_multi_ai_eoc, 0);
		if (ret)
			break;

		data[n] = (readw(dev->mmio + ICP_MULTI_AI) >> 4) & 0x0fff;
	}

	return ret ? ret : n;
}

static int icp_multi_ao_ready(struct comedi_device *dev,
			      struct comedi_subdevice *s,
			      struct comedi_insn *insn,
			      unsigned long context)
{
	unsigned int status;

	status = readw(dev->mmio + ICP_MULTI_DAC_CSR);
	if ((status & ICP_MULTI_DAC_CSR_BSY) == 0)
		return 0;
	return -EBUSY;
}

static int icp_multi_ao_insn_write(struct comedi_device *dev,
				   struct comedi_subdevice *s,
				   struct comedi_insn *insn,
				   unsigned int *data)
{
	unsigned int chan = CR_CHAN(insn->chanspec);
	unsigned int range = CR_RANGE(insn->chanspec);
	unsigned int dac_csr;
	int i;

	/* Select channel and range */
	dac_csr = ICP_MULTI_DAC_CSR_CHAN(chan);
	dac_csr |= range_codes_analog[range];
	writew(dac_csr, dev->mmio + ICP_MULTI_DAC_CSR);

	for (i = 0; i < insn->n; i++) {
		unsigned int val = data[i];
		int ret;

		/* Wait for analog output to be ready for new data */
		ret = comedi_timeout(dev, s, insn, icp_multi_ao_ready, 0);
		if (ret)
			return ret;

		writew(val, dev->mmio + ICP_MULTI_AO);

		/* Set start conversion bit to write data to channel */
		writew(dac_csr | ICP_MULTI_DAC_CSR_ST,
		       dev->mmio + ICP_MULTI_DAC_CSR);

		s->readback[chan] = val;
	}

	return insn->n;
}

static int icp_multi_di_insn_bits(struct comedi_device *dev,
				  struct comedi_subdevice *s,
				  struct comedi_insn *insn,
				  unsigned int *data)
{
	data[1] = readw(dev->mmio + ICP_MULTI_DI);

	return insn->n;
}

static int icp_multi_do_insn_bits(struct comedi_device *dev,
				  struct comedi_subdevice *s,
				  struct comedi_insn *insn,
				  unsigned int *data)
{
	if (comedi_dio_update_state(s, data))
		writew(s->state, dev->mmio + ICP_MULTI_DO);

	data[1] = s->state;

	return insn->n;
}

static int icp_multi_reset(struct comedi_device *dev)
{
	int i;

	/* Disable all interrupts and clear any requests */
	writew(0, dev->mmio + ICP_MULTI_INT_EN);
	writew(ICP_MULTI_INT_MASK, dev->mmio + ICP_MULTI_INT_STAT);

	/* Reset the analog output channels to 0V */
	for (i = 0; i < 4; i++) {
		unsigned int dac_csr = ICP_MULTI_DAC_CSR_CHAN(i);

		/* Select channel and 0..5V range */
		writew(dac_csr, dev->mmio + ICP_MULTI_DAC_CSR);

		/* Output 0V */
		writew(0, dev->mmio + ICP_MULTI_AO);

		/* Set start conversion bit to write data to channel */
		writew(dac_csr | ICP_MULTI_DAC_CSR_ST,
		       dev->mmio + ICP_MULTI_DAC_CSR);
		udelay(1);
	}

	/* Digital outputs to 0 */
	writew(0, dev->mmio + ICP_MULTI_DO);

	return 0;
}

static int icp_multi_auto_attach(struct comedi_device *dev,
				 unsigned long context_unused)
{
	struct pci_dev *pcidev = comedi_to_pci_dev(dev);
	struct comedi_subdevice *s;
	int ret;

	ret = comedi_pci_enable(dev);
	if (ret)
		return ret;

	dev->mmio = pci_ioremap_bar(pcidev, 2);
	if (!dev->mmio)
		return -ENOMEM;

	ret = comedi_alloc_subdevices(dev, 4);
	if (ret)
		return ret;

	icp_multi_reset(dev);

	/* Analog Input subdevice */
	s = &dev->subdevices[0];
	s->type		= COMEDI_SUBD_AI;
	s->subdev_flags	= SDF_READABLE | SDF_COMMON | SDF_GROUND | SDF_DIFF;
	s->n_chan	= 16;
	s->maxdata	= 0x0fff;
	s->range_table	= &icp_multi_ranges;
	s->insn_read	= icp_multi_ai_insn_read;

	/* Analog Output subdevice */
	s = &dev->subdevices[1];
	s->type		= COMEDI_SUBD_AO;
	s->subdev_flags	= SDF_WRITABLE | SDF_GROUND | SDF_COMMON;
	s->n_chan	= 4;
	s->maxdata	= 0x0fff;
	s->range_table	= &icp_multi_ranges;
	s->insn_write	= icp_multi_ao_insn_write;

	ret = comedi_alloc_subdev_readback(s);
	if (ret)
		return ret;

	/* Digital Input subdevice */
	s = &dev->subdevices[2];
	s->type		= COMEDI_SUBD_DI;
	s->subdev_flags	= SDF_READABLE;
	s->n_chan	= 16;
	s->maxdata	= 1;
	s->range_table	= &range_digital;
	s->insn_bits	= icp_multi_di_insn_bits;

	/* Digital Output subdevice */
	s = &dev->subdevices[3];
	s->type		= COMEDI_SUBD_DO;
	s->subdev_flags	= SDF_WRITABLE;
	s->n_chan	= 8;
	s->maxdata	= 1;
	s->range_table	= &range_digital;
	s->insn_bits	= icp_multi_do_insn_bits;

	return 0;
}

static struct comedi_driver icp_multi_driver = {
	.driver_name	= "icp_multi",
	.module		= THIS_MODULE,
	.auto_attach	= icp_multi_auto_attach,
	.detach		= comedi_pci_detach,
};

static int icp_multi_pci_probe(struct pci_dev *dev,
			       const struct pci_device_id *id)
{
	return comedi_pci_auto_config(dev, &icp_multi_driver, id->driver_data);
}

static const struct pci_device_id icp_multi_pci_table[] = {
	{ PCI_DEVICE(PCI_VENDOR_ID_ICP, 0x8000) },
	{ 0 }
};
MODULE_DEVICE_TABLE(pci, icp_multi_pci_table);

static struct pci_driver icp_multi_pci_driver = {
	.name		= "icp_multi",
	.id_table	= icp_multi_pci_table,
	.probe		= icp_multi_pci_probe,
	.remove		= comedi_pci_auto_unconfig,
};
module_comedi_pci_driver(icp_multi_driver, icp_multi_pci_driver);

MODULE_AUTHOR("Comedi http://www.comedi.org");
MODULE_DESCRIPTION("Comedi driver for Inova ICP_MULTI board");
MODULE_LICENSE("GPL");