// SPDX-License-Identifier: GPL-2.0+
/*
 * COMEDI driver for Advantech PCI-1720U
 * Copyright (c) 2015 H Hartley Sweeten <hsweeten@visionengravers.com>
 *
 * Separated from the adv_pci1710 driver written by:
 * Michal Dobes <dobes@tesnet.cz>
 *
 * COMEDI - Linux Control and Measurement Device Interface
 * Copyright (C) 2000 David A. Schleef <ds@schleef.org>
 */

/*
 * Driver: adv_pci1720
 * Description: 4-channel Isolated D/A Output board
 * Devices: [Advantech] PCI-7120U (adv_pci1720)
 * Author: H Hartley Sweeten <hsweeten@visionengravers.com>
 * Updated: Fri, 29 Oct 2015 17:19:35 -0700
 * Status: untested
 *
 * Configuration options: not applicable, uses PCI auto config
 *
 * The PCI-1720 has 4 isolated 12-bit analog output channels with multiple
 * output ranges. It also has a BoardID switch to allow differentiating
 * multiple boards in the system.
 *
 * The analog outputs can operate in two modes, immediate and synchronized.
 * This driver currently does not support the synchronized output mode.
 *
 * Jumpers JP1 to JP4 are used to set the current sink ranges for each
 * analog output channel. In order to use the current sink ranges, the
 * unipolar 5V range must be used. The voltage output and sink output for
 * each channel is available on the connector as separate pins.
 *
 * Jumper JP5 controls the "hot" reset state of the analog outputs.
 * Depending on its setting, the analog outputs will either keep the
 * last settings and output values or reset to the default state after
 * a "hot" reset. The default state for all channels is uniploar 5V range
 * and all the output values are 0V. To allow this feature to work, the
 * analog outputs are not "reset" when the driver attaches.
 */

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

/*
 * PCI BAR2 Register map (dev->iobase)
 */
#define PCI1720_AO_LSB_REG(x)           (0x00 + ((x) * 2))
#define PCI1720_AO_MSB_REG(x)           (0x01 + ((x) * 2))
#define PCI1720_AO_RANGE_REG            0x08
#define PCI1720_AO_RANGE(c, r)          (((r) & 0x3) << ((c) * 2))
#define PCI1720_AO_RANGE_MASK(c)        PCI1720_AO_RANGE((c), 0x3)
#define PCI1720_SYNC_REG                0x09
#define PCI1720_SYNC_CTRL_REG           0x0f
#define PCI1720_SYNC_CTRL_SC0           BIT(0)
#define PCI1720_BOARDID_REG             0x14

static const struct comedi_lrange pci1720_ao_range = {
        4, {
                UNI_RANGE(5),
                UNI_RANGE(10),
                BIP_RANGE(5),
                BIP_RANGE(10)
        }
};

static int pci1720_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 val;
        int i;

        /* set the channel range and polarity */
        val = inb(dev->iobase + PCI1720_AO_RANGE_REG);
        val &= ~PCI1720_AO_RANGE_MASK(chan);
        val |= PCI1720_AO_RANGE(chan, range);
        outb(val, dev->iobase + PCI1720_AO_RANGE_REG);

        val = s->readback[chan];
        for (i = 0; i < insn->n; i++) {
                val = data[i];

                outb(val & 0xff, dev->iobase + PCI1720_AO_LSB_REG(chan));
                outb((val >> 8) & 0xff, dev->iobase + PCI1720_AO_MSB_REG(chan));

                /* conversion time is 2us (500 kHz throughput) */
                usleep_range(2, 100);
        }

        s->readback[chan] = val;

        return insn->n;
}

static int pci1720_di_insn_bits(struct comedi_device *dev,
                                struct comedi_subdevice *s,
                                struct comedi_insn *insn,
                                unsigned int *data)
{
        data[1] = inb(dev->iobase + PCI1720_BOARDID_REG);

        return insn->n;
}

static int pci1720_auto_attach(struct comedi_device *dev,
                               unsigned long context)
{
        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->iobase = pci_resource_start(pcidev, 2);

        ret = comedi_alloc_subdevices(dev, 2);
        if (ret)
                return ret;

        /* Analog Output subdevice */
        s = &dev->subdevices[0];
        s->type         = COMEDI_SUBD_AO;
        s->subdev_flags = SDF_WRITABLE;
        s->n_chan       = 4;
        s->maxdata      = 0x0fff;
        s->range_table  = &pci1720_ao_range;
        s->insn_write   = pci1720_ao_insn_write;

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

        /* Digital Input subdevice (BoardID SW1) */
        s = &dev->subdevices[1];
        s->type         = COMEDI_SUBD_DI;
        s->subdev_flags = SDF_READABLE;
        s->n_chan       = 4;
        s->maxdata      = 1;
        s->range_table  = &range_digital;
        s->insn_bits    = pci1720_di_insn_bits;

        /* disable synchronized output, channels update when written */
        outb(0, dev->iobase + PCI1720_SYNC_CTRL_REG);

        return 0;
}

static struct comedi_driver adv_pci1720_driver = {
        .driver_name    = "adv_pci1720",
        .module         = THIS_MODULE,
        .auto_attach    = pci1720_auto_attach,
        .detach         = comedi_pci_detach,
};

static int adv_pci1720_pci_probe(struct pci_dev *dev,
                                 const struct pci_device_id *id)
{
        return comedi_pci_auto_config(dev, &adv_pci1720_driver,
                                      id->driver_data);
}

static const struct pci_device_id adv_pci1720_pci_table[] = {
        { PCI_DEVICE(PCI_VENDOR_ID_ADVANTECH, 0x1720) },
        { 0 }
};
MODULE_DEVICE_TABLE(pci, adv_pci1720_pci_table);

static struct pci_driver adv_pci1720_pci_driver = {
        .name           = "adv_pci1720",
        .id_table       = adv_pci1720_pci_table,
        .probe          = adv_pci1720_pci_probe,
        .remove         = comedi_pci_auto_unconfig,
};
module_comedi_pci_driver(adv_pci1720_driver, adv_pci1720_pci_driver);

MODULE_AUTHOR("H Hartley Sweeten <hsweeten@visionengravers.com>");
MODULE_DESCRIPTION("Comedi driver for Advantech PCI-1720 Analog Output board");
MODULE_LICENSE("GPL");