// SPDX-License-Identifier: GPL-2.0+
/*
 * rti802.c
 * Comedi driver for Analog Devices RTI-802 board
 *
 * COMEDI - Linux Control and Measurement Device Interface
 * Copyright (C) 1999 Anders Blomdell <anders.blomdell@control.lth.se>
 */

/*
 * Driver: rti802
 * Description: Analog Devices RTI-802
 * Author: Anders Blomdell <anders.blomdell@control.lth.se>
 * Devices: [Analog Devices] RTI-802 (rti802)
 * Status: works
 *
 * Configuration Options:
 *   [0] - i/o base
 *   [1] - unused
 *   [2,4,6,8,10,12,14,16] - dac#[0-7]  0=two's comp, 1=straight
 *   [3,5,7,9,11,13,15,17] - dac#[0-7]  0=bipolar, 1=unipolar
 */

#include <linux/module.h>
#include <linux/comedi/comedidev.h>

/*
 * Register I/O map
 */
#define RTI802_SELECT           0x00
#define RTI802_DATALOW          0x01
#define RTI802_DATAHIGH         0x02

struct rti802_private {
        enum {
                dac_2comp, dac_straight
        } dac_coding[8];
        const struct comedi_lrange *range_type_list[8];
};

static int rti802_ao_insn_write(struct comedi_device *dev,
                                struct comedi_subdevice *s,
                                struct comedi_insn *insn,
                                unsigned int *data)
{
        struct rti802_private *devpriv = dev->private;
        unsigned int chan = CR_CHAN(insn->chanspec);
        int i;

        outb(chan, dev->iobase + RTI802_SELECT);

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

                s->readback[chan] = val;

                /* munge offset binary to two's complement if needed */
                if (devpriv->dac_coding[chan] == dac_2comp)
                        val = comedi_offset_munge(s, val);

                outb(val & 0xff, dev->iobase + RTI802_DATALOW);
                outb((val >> 8) & 0xff, dev->iobase + RTI802_DATAHIGH);
        }

        return insn->n;
}

static int rti802_attach(struct comedi_device *dev, struct comedi_devconfig *it)
{
        struct rti802_private *devpriv;
        struct comedi_subdevice *s;
        int i;
        int ret;

        ret = comedi_request_region(dev, it->options[0], 0x04);
        if (ret)
                return ret;

        devpriv = comedi_alloc_devpriv(dev, sizeof(*devpriv));
        if (!devpriv)
                return -ENOMEM;

        ret = comedi_alloc_subdevices(dev, 1);
        if (ret)
                return ret;

        /* Analog Output subdevice */
        s = &dev->subdevices[0];
        s->type         = COMEDI_SUBD_AO;
        s->subdev_flags = SDF_WRITABLE;
        s->maxdata      = 0xfff;
        s->n_chan       = 8;
        s->insn_write   = rti802_ao_insn_write;

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

        s->range_table_list = devpriv->range_type_list;
        for (i = 0; i < 8; i++) {
                devpriv->dac_coding[i] = (it->options[3 + 2 * i])
                        ? (dac_straight) : (dac_2comp);
                devpriv->range_type_list[i] = (it->options[2 + 2 * i])
                        ? &range_unipolar10 : &range_bipolar10;
        }

        return 0;
}

static struct comedi_driver rti802_driver = {
        .driver_name    = "rti802",
        .module         = THIS_MODULE,
        .attach         = rti802_attach,
        .detach         = comedi_legacy_detach,
};
module_comedi_driver(rti802_driver);

MODULE_AUTHOR("Comedi https://www.comedi.org");
MODULE_DESCRIPTION("Comedi driver for Analog Devices RTI-802 board");
MODULE_LICENSE("GPL");