// SPDX-License-Identifier: GPL-2.0+
/*
 *  comedi/drivers/mf6x4.c
 *  Driver for Humusoft MF634 and MF624 Data acquisition cards
 *
 *  COMEDI - Linux Control and Measurement Device Interface
 *  Copyright (C) 2000 David A. Schleef <ds@schleef.org>
 */
/*
 * Driver: mf6x4
 * Description: Humusoft MF634 and MF624 Data acquisition card driver
 * Devices: [Humusoft] MF634 (mf634), MF624 (mf624)
 * Author: Rostislav Lisovy <lisovy@gmail.com>
 * Status: works
 * Updated:
 * Configuration Options: none
 */

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

/* Registers present in BAR0 memory region */
#define MF624_GPIOC_REG         0x54

#define MF6X4_GPIOC_EOLC        BIT(17) /* End Of Last Conversion */
#define MF6X4_GPIOC_LDAC        BIT(23) /* Load DACs */
#define MF6X4_GPIOC_DACEN       BIT(26)

/* BAR1 registers */
#define MF6X4_ADDATA_REG        0x00
#define MF6X4_ADCTRL_REG        0x00
#define MF6X4_ADCTRL_CHAN(x)    BIT(chan)
#define MF6X4_DIN_REG           0x10
#define MF6X4_DIN_MASK          0xff
#define MF6X4_DOUT_REG          0x10
#define MF6X4_ADSTART_REG       0x20
#define MF6X4_DAC_REG(x)        (0x20 + ((x) * 2))

/* BAR2 registers */
#define MF634_GPIOC_REG         0x68

enum mf6x4_boardid {
        BOARD_MF634,
        BOARD_MF624,
};

struct mf6x4_board {
        const char *name;
        /* We need to keep track of the order of BARs used by the cards */
        unsigned int bar_nums[3];
};

static const struct mf6x4_board mf6x4_boards[] = {
        [BOARD_MF634] = {
                .name           = "mf634",
                .bar_nums       = {0, 2, 3},
        },
        [BOARD_MF624] = {
                .name           = "mf624",
                .bar_nums       = {0, 2, 4},
        },
};

struct mf6x4_private {
        /*
         * Documentation for both MF634 and MF624 describes registers
         * present in BAR0, 1 and 2 regions.
         * The real (i.e. in HW) BAR numbers are different for MF624
         * and MF634 yet we will call them 0, 1, 2
         */
        void __iomem *bar0_mem;
        void __iomem *bar2_mem;

        /*
         * This configuration register has the same function and fields
         * for both cards however it lies in different BARs on different
         * offsets -- this variable makes the access easier
         */
        void __iomem *gpioc_reg;
};

static int mf6x4_di_insn_bits(struct comedi_device *dev,
                              struct comedi_subdevice *s,
                              struct comedi_insn *insn,
                              unsigned int *data)
{
        data[1] = ioread16(dev->mmio + MF6X4_DIN_REG) & MF6X4_DIN_MASK;

        return insn->n;
}

static int mf6x4_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))
                iowrite16(s->state, dev->mmio + MF6X4_DOUT_REG);

        data[1] = s->state;

        return insn->n;
}

static int mf6x4_ai_eoc(struct comedi_device *dev,
                        struct comedi_subdevice *s,
                        struct comedi_insn *insn,
                        unsigned long context)
{
        struct mf6x4_private *devpriv = dev->private;
        unsigned int status;

        /* EOLC goes low at end of conversion. */
        status = ioread32(devpriv->gpioc_reg);
        if ((status & MF6X4_GPIOC_EOLC) == 0)
                return 0;
        return -EBUSY;
}

static int mf6x4_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 d;
        int ret;
        int i;

        /* Set the ADC channel number in the scan list */
        iowrite16(MF6X4_ADCTRL_CHAN(chan), dev->mmio + MF6X4_ADCTRL_REG);

        for (i = 0; i < insn->n; i++) {
                /* Trigger ADC conversion by reading ADSTART */
                ioread16(dev->mmio + MF6X4_ADSTART_REG);

                ret = comedi_timeout(dev, s, insn, mf6x4_ai_eoc, 0);
                if (ret)
                        return ret;

                /* Read the actual value */
                d = ioread16(dev->mmio + MF6X4_ADDATA_REG);
                d &= s->maxdata;
                /* munge the 2's complement data to offset binary */
                data[i] = comedi_offset_munge(s, d);
        }

        iowrite16(0x0, dev->mmio + MF6X4_ADCTRL_REG);

        return insn->n;
}

static int mf6x4_ao_insn_write(struct comedi_device *dev,
                               struct comedi_subdevice *s,
                               struct comedi_insn *insn,
                               unsigned int *data)
{
        struct mf6x4_private *devpriv = dev->private;
        unsigned int chan = CR_CHAN(insn->chanspec);
        unsigned int val = s->readback[chan];
        unsigned int gpioc;
        int i;

        /* Enable instantaneous update of converters outputs + Enable DACs */
        gpioc = ioread32(devpriv->gpioc_reg);
        iowrite32((gpioc & ~MF6X4_GPIOC_LDAC) | MF6X4_GPIOC_DACEN,
                  devpriv->gpioc_reg);

        for (i = 0; i < insn->n; i++) {
                val = data[i];
                iowrite16(val, dev->mmio + MF6X4_DAC_REG(chan));
        }
        s->readback[chan] = val;

        return insn->n;
}

static int mf6x4_auto_attach(struct comedi_device *dev, unsigned long context)
{
        struct pci_dev *pcidev = comedi_to_pci_dev(dev);
        const struct mf6x4_board *board = NULL;
        struct mf6x4_private *devpriv;
        struct comedi_subdevice *s;
        int ret;

        if (context < ARRAY_SIZE(mf6x4_boards))
                board = &mf6x4_boards[context];
        else
                return -ENODEV;

        dev->board_ptr = board;
        dev->board_name = board->name;

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

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

        devpriv->bar0_mem = pci_ioremap_bar(pcidev, board->bar_nums[0]);
        if (!devpriv->bar0_mem)
                return -ENODEV;

        dev->mmio = pci_ioremap_bar(pcidev, board->bar_nums[1]);
        if (!dev->mmio)
                return -ENODEV;

        devpriv->bar2_mem = pci_ioremap_bar(pcidev, board->bar_nums[2]);
        if (!devpriv->bar2_mem)
                return -ENODEV;

        if (board == &mf6x4_boards[BOARD_MF634])
                devpriv->gpioc_reg = devpriv->bar2_mem + MF634_GPIOC_REG;
        else
                devpriv->gpioc_reg = devpriv->bar0_mem + MF624_GPIOC_REG;

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

        /* Analog Input subdevice */
        s = &dev->subdevices[0];
        s->type         = COMEDI_SUBD_AI;
        s->subdev_flags = SDF_READABLE | SDF_GROUND;
        s->n_chan       = 8;
        s->maxdata      = 0x3fff;
        s->range_table  = &range_bipolar10;
        s->insn_read    = mf6x4_ai_insn_read;

        /* Analog Output subdevice */
        s = &dev->subdevices[1];
        s->type         = COMEDI_SUBD_AO;
        s->subdev_flags = SDF_WRITABLE;
        s->n_chan       = 8;
        s->maxdata      = 0x3fff;
        s->range_table  = &range_bipolar10;
        s->insn_write   = mf6x4_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       = 8;
        s->maxdata      = 1;
        s->range_table  = &range_digital;
        s->insn_bits    = mf6x4_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    = mf6x4_do_insn_bits;

        return 0;
}

static void mf6x4_detach(struct comedi_device *dev)
{
        struct mf6x4_private *devpriv = dev->private;

        if (devpriv) {
                if (devpriv->bar0_mem)
                        iounmap(devpriv->bar0_mem);
                if (devpriv->bar2_mem)
                        iounmap(devpriv->bar2_mem);
        }
        comedi_pci_detach(dev);
}

static struct comedi_driver mf6x4_driver = {
        .driver_name    = "mf6x4",
        .module         = THIS_MODULE,
        .auto_attach    = mf6x4_auto_attach,
        .detach         = mf6x4_detach,
};

static int mf6x4_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
{
        return comedi_pci_auto_config(dev, &mf6x4_driver, id->driver_data);
}

static const struct pci_device_id mf6x4_pci_table[] = {
        { PCI_VDEVICE(HUMUSOFT, 0x0634), BOARD_MF634 },
        { PCI_VDEVICE(HUMUSOFT, 0x0624), BOARD_MF624 },
        { 0 }
};
MODULE_DEVICE_TABLE(pci, mf6x4_pci_table);

static struct pci_driver mf6x4_pci_driver = {
        .name           = "mf6x4",
        .id_table       = mf6x4_pci_table,
        .probe          = mf6x4_pci_probe,
        .remove         = comedi_pci_auto_unconfig,
};

module_comedi_pci_driver(mf6x4_driver, mf6x4_pci_driver);

MODULE_AUTHOR("Rostislav Lisovy <lisovy@gmail.com>");
MODULE_DESCRIPTION("Comedi MF634 and MF624 DAQ cards driver");
MODULE_LICENSE("GPL");