// SPDX-License-Identifier: GPL-2.0+
/*
 * pcl726.c
 * Comedi driver for 6/12-Channel D/A Output and DIO cards
 *
 * COMEDI - Linux Control and Measurement Device Interface
 * Copyright (C) 1998 David A. Schleef <ds@schleef.org>
 */

/*
 * Driver: pcl726
 * Description: Advantech PCL-726 & compatibles
 * Author: David A. Schleef <ds@schleef.org>
 * Status: untested
 * Devices: [Advantech] PCL-726 (pcl726), PCL-727 (pcl727), PCL-728 (pcl728),
 *   [ADLink] ACL-6126 (acl6126), ACL-6128 (acl6128)
 *
 * Configuration Options:
 *   [0]  - IO Base
 *   [1]  - IRQ (ACL-6126 only)
 *   [2]  - D/A output range for channel 0
 *   [3]  - D/A output range for channel 1
 *
 * Boards with > 2 analog output channels:
 *   [4]  - D/A output range for channel 2
 *   [5]  - D/A output range for channel 3
 *   [6]  - D/A output range for channel 4
 *   [7]  - D/A output range for channel 5
 *
 * Boards with > 6 analog output channels:
 *   [8]  - D/A output range for channel 6
 *   [9]  - D/A output range for channel 7
 *   [10] - D/A output range for channel 8
 *   [11] - D/A output range for channel 9
 *   [12] - D/A output range for channel 10
 *   [13] - D/A output range for channel 11
 *
 * For PCL-726 the D/A output ranges are:
 *   0: 0-5V, 1: 0-10V, 2: +/-5V, 3: +/-10V, 4: 4-20mA, 5: unknown
 *
 * For PCL-727:
 *   0: 0-5V, 1: 0-10V, 2: +/-5V, 3: 4-20mA
 *
 * For PCL-728 and ACL-6128:
 *   0: 0-5V, 1: 0-10V, 2: +/-5V, 3: +/-10V, 4: 4-20mA, 5: 0-20mA
 *
 * For ACL-6126:
 *   0: 0-5V, 1: 0-10V, 2: +/-5V, 3: +/-10V, 4: 4-20mA
 */

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

#define PCL726_AO_MSB_REG(x)    (0x00 + ((x) * 2))
#define PCL726_AO_LSB_REG(x)    (0x01 + ((x) * 2))
#define PCL726_DO_MSB_REG       0x0c
#define PCL726_DO_LSB_REG       0x0d
#define PCL726_DI_MSB_REG       0x0e
#define PCL726_DI_LSB_REG       0x0f

#define PCL727_DI_MSB_REG       0x00
#define PCL727_DI_LSB_REG       0x01
#define PCL727_DO_MSB_REG       0x18
#define PCL727_DO_LSB_REG       0x19

static const struct comedi_lrange *const rangelist_726[] = {
        &range_unipolar5,
        &range_unipolar10,
        &range_bipolar5,
        &range_bipolar10,
        &range_4_20mA,
        &range_unknown
};

static const struct comedi_lrange *const rangelist_727[] = {
        &range_unipolar5,
        &range_unipolar10,
        &range_bipolar5,
        &range_4_20mA
};

static const struct comedi_lrange *const rangelist_728[] = {
        &range_unipolar5,
        &range_unipolar10,
        &range_bipolar5,
        &range_bipolar10,
        &range_4_20mA,
        &range_0_20mA
};

struct pcl726_board {
        const char *name;
        unsigned long io_len;
        unsigned int irq_mask;
        const struct comedi_lrange *const *ao_ranges;
        int ao_num_ranges;
        int ao_nchan;
        unsigned int have_dio:1;
        unsigned int is_pcl727:1;
};

static const struct pcl726_board pcl726_boards[] = {
        {
                .name           = "pcl726",
                .io_len         = 0x10,
                .ao_ranges      = &rangelist_726[0],
                .ao_num_ranges  = ARRAY_SIZE(rangelist_726),
                .ao_nchan       = 6,
                .have_dio       = 1,
        }, {
                .name           = "pcl727",
                .io_len         = 0x20,
                .ao_ranges      = &rangelist_727[0],
                .ao_num_ranges  = ARRAY_SIZE(rangelist_727),
                .ao_nchan       = 12,
                .have_dio       = 1,
                .is_pcl727      = 1,
        }, {
                .name           = "pcl728",
                .io_len         = 0x08,
                .ao_num_ranges  = ARRAY_SIZE(rangelist_728),
                .ao_ranges      = &rangelist_728[0],
                .ao_nchan       = 2,
        }, {
                .name           = "acl6126",
                .io_len         = 0x10,
                .irq_mask       = 0x96e8,
                .ao_num_ranges  = ARRAY_SIZE(rangelist_726),
                .ao_ranges      = &rangelist_726[0],
                .ao_nchan       = 6,
                .have_dio       = 1,
        }, {
                .name           = "acl6128",
                .io_len         = 0x08,
                .ao_num_ranges  = ARRAY_SIZE(rangelist_728),
                .ao_ranges      = &rangelist_728[0],
                .ao_nchan       = 2,
        },
};

struct pcl726_private {
        const struct comedi_lrange *rangelist[12];
        unsigned int cmd_running:1;
};

static int pcl726_intr_insn_bits(struct comedi_device *dev,
                                 struct comedi_subdevice *s,
                                 struct comedi_insn *insn,
                                 unsigned int *data)
{
        data[1] = 0;
        return insn->n;
}

static int pcl726_intr_cmdtest(struct comedi_device *dev,
                               struct comedi_subdevice *s,
                               struct comedi_cmd *cmd)
{
        int err = 0;

        /* Step 1 : check if triggers are trivially valid */

        err |= comedi_check_trigger_src(&cmd->start_src, TRIG_NOW);
        err |= comedi_check_trigger_src(&cmd->scan_begin_src, TRIG_EXT);
        err |= comedi_check_trigger_src(&cmd->convert_src, TRIG_FOLLOW);
        err |= comedi_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT);
        err |= comedi_check_trigger_src(&cmd->stop_src, TRIG_NONE);

        if (err)
                return 1;

        /* Step 2a : make sure trigger sources are unique */
        /* Step 2b : and mutually compatible */

        /* Step 3: check if arguments are trivially valid */

        err |= comedi_check_trigger_arg_is(&cmd->start_arg, 0);
        err |= comedi_check_trigger_arg_is(&cmd->scan_begin_arg, 0);
        err |= comedi_check_trigger_arg_is(&cmd->convert_arg, 0);
        err |= comedi_check_trigger_arg_is(&cmd->scan_end_arg,
                                           cmd->chanlist_len);
        err |= comedi_check_trigger_arg_is(&cmd->stop_arg, 0);

        if (err)
                return 3;

        /* Step 4: fix up any arguments */

        /* Step 5: check channel list if it exists */

        return 0;
}

static int pcl726_intr_cmd(struct comedi_device *dev,
                           struct comedi_subdevice *s)
{
        struct pcl726_private *devpriv = dev->private;

        devpriv->cmd_running = 1;

        return 0;
}

static int pcl726_intr_cancel(struct comedi_device *dev,
                              struct comedi_subdevice *s)
{
        struct pcl726_private *devpriv = dev->private;

        devpriv->cmd_running = 0;

        return 0;
}

static irqreturn_t pcl726_interrupt(int irq, void *d)
{
        struct comedi_device *dev = d;
        struct comedi_subdevice *s = dev->read_subdev;
        struct pcl726_private *devpriv = dev->private;

        if (devpriv->cmd_running) {
                unsigned short val = 0;

                pcl726_intr_cancel(dev, s);

                comedi_buf_write_samples(s, &val, 1);
                comedi_handle_events(dev, s);
        }

        return IRQ_HANDLED;
}

static int pcl726_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);
        int i;

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

                s->readback[chan] = val;

                /* bipolar data to the DAC is two's complement */
                if (comedi_chan_range_is_bipolar(s, chan, range))
                        val = comedi_offset_munge(s, val);

                /* order is important, MSB then LSB */
                outb((val >> 8) & 0xff, dev->iobase + PCL726_AO_MSB_REG(chan));
                outb(val & 0xff, dev->iobase + PCL726_AO_LSB_REG(chan));
        }

        return insn->n;
}

static int pcl726_di_insn_bits(struct comedi_device *dev,
                               struct comedi_subdevice *s,
                               struct comedi_insn *insn,
                               unsigned int *data)
{
        const struct pcl726_board *board = dev->board_ptr;
        unsigned int val;

        if (board->is_pcl727) {
                val = inb(dev->iobase + PCL727_DI_LSB_REG);
                val |= (inb(dev->iobase + PCL727_DI_MSB_REG) << 8);
        } else {
                val = inb(dev->iobase + PCL726_DI_LSB_REG);
                val |= (inb(dev->iobase + PCL726_DI_MSB_REG) << 8);
        }

        data[1] = val;

        return insn->n;
}

static int pcl726_do_insn_bits(struct comedi_device *dev,
                               struct comedi_subdevice *s,
                               struct comedi_insn *insn,
                               unsigned int *data)
{
        const struct pcl726_board *board = dev->board_ptr;
        unsigned long io = dev->iobase;
        unsigned int mask;

        mask = comedi_dio_update_state(s, data);
        if (mask) {
                if (board->is_pcl727) {
                        if (mask & 0x00ff)
                                outb(s->state & 0xff, io + PCL727_DO_LSB_REG);
                        if (mask & 0xff00)
                                outb((s->state >> 8), io + PCL727_DO_MSB_REG);
                } else {
                        if (mask & 0x00ff)
                                outb(s->state & 0xff, io + PCL726_DO_LSB_REG);
                        if (mask & 0xff00)
                                outb((s->state >> 8), io + PCL726_DO_MSB_REG);
                }
        }

        data[1] = s->state;

        return insn->n;
}

static int pcl726_attach(struct comedi_device *dev,
                         struct comedi_devconfig *it)
{
        const struct pcl726_board *board = dev->board_ptr;
        struct pcl726_private *devpriv;
        struct comedi_subdevice *s;
        int subdev;
        int ret;
        int i;

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

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

        /*
         * Hook up the external trigger source interrupt only if the
         * user config option is valid and the board supports interrupts.
         */
        if (it->options[1] > 0 && it->options[1] < 16 &&
            (board->irq_mask & (1U << it->options[1]))) {
                ret = request_irq(it->options[1], pcl726_interrupt, 0,
                                  dev->board_name, dev);
                if (ret == 0) {
                        /* External trigger source is from Pin-17 of CN3 */
                        dev->irq = it->options[1];
                }
        }

        /* setup the per-channel analog output range_table_list */
        for (i = 0; i < 12; i++) {
                unsigned int opt = it->options[2 + i];

                if (opt < board->ao_num_ranges && i < board->ao_nchan)
                        devpriv->rangelist[i] = board->ao_ranges[opt];
                else
                        devpriv->rangelist[i] = &range_unknown;
        }

        subdev = board->have_dio ? 3 : 1;
        if (dev->irq)
                subdev++;
        ret = comedi_alloc_subdevices(dev, subdev);
        if (ret)
                return ret;

        subdev = 0;

        /* Analog Output subdevice */
        s = &dev->subdevices[subdev++];
        s->type         = COMEDI_SUBD_AO;
        s->subdev_flags = SDF_WRITABLE | SDF_GROUND;
        s->n_chan       = board->ao_nchan;
        s->maxdata      = 0x0fff;
        s->range_table_list = devpriv->rangelist;
        s->insn_write   = pcl726_ao_insn_write;

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

        if (board->have_dio) {
                /* Digital Input subdevice */
                s = &dev->subdevices[subdev++];
                s->type         = COMEDI_SUBD_DI;
                s->subdev_flags = SDF_READABLE;
                s->n_chan       = 16;
                s->maxdata      = 1;
                s->insn_bits    = pcl726_di_insn_bits;
                s->range_table  = &range_digital;

                /* Digital Output subdevice */
                s = &dev->subdevices[subdev++];
                s->type         = COMEDI_SUBD_DO;
                s->subdev_flags = SDF_WRITABLE;
                s->n_chan       = 16;
                s->maxdata      = 1;
                s->insn_bits    = pcl726_do_insn_bits;
                s->range_table  = &range_digital;
        }

        if (dev->irq) {
                /* Digital Input subdevice - Interrupt support */
                s = &dev->subdevices[subdev++];
                dev->read_subdev = s;
                s->type         = COMEDI_SUBD_DI;
                s->subdev_flags = SDF_READABLE | SDF_CMD_READ;
                s->n_chan       = 1;
                s->maxdata      = 1;
                s->range_table  = &range_digital;
                s->insn_bits    = pcl726_intr_insn_bits;
                s->len_chanlist = 1;
                s->do_cmdtest   = pcl726_intr_cmdtest;
                s->do_cmd       = pcl726_intr_cmd;
                s->cancel       = pcl726_intr_cancel;
        }

        return 0;
}

static struct comedi_driver pcl726_driver = {
        .driver_name    = "pcl726",
        .module         = THIS_MODULE,
        .attach         = pcl726_attach,
        .detach         = comedi_legacy_detach,
        .board_name     = &pcl726_boards[0].name,
        .num_names      = ARRAY_SIZE(pcl726_boards),
        .offset         = sizeof(struct pcl726_board),
};
module_comedi_driver(pcl726_driver);

MODULE_AUTHOR("Comedi https://www.comedi.org");
MODULE_DESCRIPTION("Comedi driver for Advantech PCL-726 & compatibles");
MODULE_LICENSE("GPL");