// SPDX-License-Identifier: GPL-2.0+
/*
 * adv_pci1724.c
 * Comedi driver for the Advantech PCI-1724U card.
 *
 * Author:  Frank Mori Hess <fmh6jj@gmail.com>
 * Copyright (C) 2013 GnuBIO Inc
 *
 * COMEDI - Linux Control and Measurement Device Interface
 * Copyright (C) 1997-8 David A. Schleef <ds@schleef.org>
 */

/*
 * Driver: adv_pci1724
 * Description: Advantech PCI-1724U
 * Devices: [Advantech] PCI-1724U (adv_pci1724)
 * Author: Frank Mori Hess <fmh6jj@gmail.com>
 * Updated: 2013-02-09
 * Status: works
 *
 * Configuration Options: not applicable, uses comedi PCI auto config
 *
 * Subdevice 0 is the analog output.
 * Subdevice 1 is the offset calibration for the analog output.
 * Subdevice 2 is the gain calibration for the analog output.
 *
 * The calibration offset and gains have quite a large effect on the
 * analog output, so it is possible to adjust the analog output to
 * have an output range significantly different from the board's
 * nominal output ranges. For a calibrated +/-10V range, the analog
 * output's offset will be set somewhere near mid-range (0x2000) and
 * its gain will be near maximum (0x3fff).
 *
 * There is really no difference between the board's documented 0-20mA
 * versus 4-20mA output ranges. To pick one or the other is simply a
 * matter of adjusting the offset and gain calibration until the board
 * outputs in the desired range.
 */

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

/*
 * PCI bar 2 Register I/O map (dev->iobase)
 */
#define PCI1724_DAC_CTRL_REG            0x00
#define PCI1724_DAC_CTRL_GX(x)          BIT(20 + ((x) / 8))
#define PCI1724_DAC_CTRL_CX(x)          (((x) % 8) << 16)
#define PCI1724_DAC_CTRL_MODE(x)        (((x) & 0x3) << 14)
#define PCI1724_DAC_CTRL_MODE_GAIN      PCI1724_DAC_CTRL_MODE(1)
#define PCI1724_DAC_CTRL_MODE_OFFSET    PCI1724_DAC_CTRL_MODE(2)
#define PCI1724_DAC_CTRL_MODE_NORMAL    PCI1724_DAC_CTRL_MODE(3)
#define PCI1724_DAC_CTRL_MODE_MASK      PCI1724_DAC_CTRL_MODE(3)
#define PCI1724_DAC_CTRL_DATA(x)        (((x) & 0x3fff) << 0)
#define PCI1724_SYNC_CTRL_REG           0x04
#define PCI1724_SYNC_CTRL_DACSTAT       BIT(1)
#define PCI1724_SYNC_CTRL_SYN           BIT(0)
#define PCI1724_EEPROM_CTRL_REG         0x08
#define PCI1724_SYNC_TRIG_REG           0x0c  /* any value works */
#define PCI1724_BOARD_ID_REG            0x10
#define PCI1724_BOARD_ID_MASK           (0xf << 0)

static const struct comedi_lrange adv_pci1724_ao_ranges = {
        4, {
                BIP_RANGE(10),
                RANGE_mA(0, 20),
                RANGE_mA(4, 20),
                RANGE_unitless(0, 1)
        }
};

static int adv_pci1724_dac_idle(struct comedi_device *dev,
                                struct comedi_subdevice *s,
                                struct comedi_insn *insn,
                                unsigned long context)
{
        unsigned int status;

        status = inl(dev->iobase + PCI1724_SYNC_CTRL_REG);
        if ((status & PCI1724_SYNC_CTRL_DACSTAT) == 0)
                return 0;
        return -EBUSY;
}

static int adv_pci1724_insn_write(struct comedi_device *dev,
                                  struct comedi_subdevice *s,
                                  struct comedi_insn *insn,
                                  unsigned int *data)
{
        unsigned long mode = (unsigned long)s->private;
        unsigned int chan = CR_CHAN(insn->chanspec);
        unsigned int ctrl;
        int ret;
        int i;

        ctrl = PCI1724_DAC_CTRL_GX(chan) | PCI1724_DAC_CTRL_CX(chan) | mode;

        /* turn off synchronous mode */
        outl(0, dev->iobase + PCI1724_SYNC_CTRL_REG);

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

                ret = comedi_timeout(dev, s, insn, adv_pci1724_dac_idle, 0);
                if (ret)
                        return ret;

                outl(ctrl | PCI1724_DAC_CTRL_DATA(val),
                     dev->iobase + PCI1724_DAC_CTRL_REG);

                s->readback[chan] = val;
        }

        return insn->n;
}

static int adv_pci1724_auto_attach(struct comedi_device *dev,
                                   unsigned long context_unused)
{
        struct pci_dev *pcidev = comedi_to_pci_dev(dev);
        struct comedi_subdevice *s;
        unsigned int board_id;
        int ret;

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

        dev->iobase = pci_resource_start(pcidev, 2);
        board_id = inl(dev->iobase + PCI1724_BOARD_ID_REG);
        dev_info(dev->class_dev, "board id: %d\n",
                 board_id & PCI1724_BOARD_ID_MASK);

        ret = comedi_alloc_subdevices(dev, 3);
        if (ret)
                return ret;

        /* Analog Output subdevice */
        s = &dev->subdevices[0];
        s->type         = COMEDI_SUBD_AO;
        s->subdev_flags = SDF_READABLE | SDF_WRITABLE | SDF_GROUND;
        s->n_chan       = 32;
        s->maxdata      = 0x3fff;
        s->range_table  = &adv_pci1724_ao_ranges;
        s->insn_write   = adv_pci1724_insn_write;
        s->private      = (void *)PCI1724_DAC_CTRL_MODE_NORMAL;

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

        /* Offset Calibration subdevice */
        s = &dev->subdevices[1];
        s->type         = COMEDI_SUBD_CALIB;
        s->subdev_flags = SDF_READABLE | SDF_WRITABLE | SDF_INTERNAL;
        s->n_chan       = 32;
        s->maxdata      = 0x3fff;
        s->insn_write   = adv_pci1724_insn_write;
        s->private      = (void *)PCI1724_DAC_CTRL_MODE_OFFSET;

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

        /* Gain Calibration subdevice */
        s = &dev->subdevices[2];
        s->type         = COMEDI_SUBD_CALIB;
        s->subdev_flags = SDF_READABLE | SDF_WRITABLE | SDF_INTERNAL;
        s->n_chan       = 32;
        s->maxdata      = 0x3fff;
        s->insn_write   = adv_pci1724_insn_write;
        s->private      = (void *)PCI1724_DAC_CTRL_MODE_GAIN;

        return comedi_alloc_subdev_readback(s);
}

static struct comedi_driver adv_pci1724_driver = {
        .driver_name    = "adv_pci1724",
        .module         = THIS_MODULE,
        .auto_attach    = adv_pci1724_auto_attach,
        .detach         = comedi_pci_detach,
};

static int adv_pci1724_pci_probe(struct pci_dev *dev,
                                 const struct pci_device_id *id)
{
        return comedi_pci_auto_config(dev, &adv_pci1724_driver,
                                      id->driver_data);
}

static const struct pci_device_id adv_pci1724_pci_table[] = {
        { PCI_DEVICE(PCI_VENDOR_ID_ADVANTECH, 0x1724) },
        { 0 }
};
MODULE_DEVICE_TABLE(pci, adv_pci1724_pci_table);

static struct pci_driver adv_pci1724_pci_driver = {
        .name           = "adv_pci1724",
        .id_table       = adv_pci1724_pci_table,
        .probe          = adv_pci1724_pci_probe,
        .remove         = comedi_pci_auto_unconfig,
};
module_comedi_pci_driver(adv_pci1724_driver, adv_pci1724_pci_driver);

MODULE_AUTHOR("Frank Mori Hess <fmh6jj@gmail.com>");
MODULE_DESCRIPTION("Advantech PCI-1724U Comedi driver");
MODULE_LICENSE("GPL");