// SPDX-License-Identifier: GPL-2.0
/*
 * UIO driver for Hilscher NetX based fieldbus cards (cifX, comX).
 * See http://www.hilscher.com for details.
 *
 * (C) 2007 Hans J. Koch <hjk@hansjkoch.de>
 * (C) 2008 Manuel Traut <manut@linutronix.de>
 *
 */

#include <linux/device.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/uio_driver.h>

#define PCI_VENDOR_ID_HILSCHER          0x15CF
#define PCI_DEVICE_ID_HILSCHER_NETX     0x0000
#define PCI_DEVICE_ID_HILSCHER_NETPLC   0x0010
#define PCI_SUBDEVICE_ID_NETPLC_RAM     0x0000
#define PCI_SUBDEVICE_ID_NETPLC_FLASH   0x0001
#define PCI_SUBDEVICE_ID_NXSB_PCA       0x3235
#define PCI_SUBDEVICE_ID_NXPCA          0x3335

#define DPM_HOST_INT_EN0        0xfff0
#define DPM_HOST_INT_STAT0      0xffe0

#define DPM_HOST_INT_MASK       0xe600ffff
#define DPM_HOST_INT_GLOBAL_EN  0x80000000

static irqreturn_t netx_handler(int irq, struct uio_info *dev_info)
{
        void __iomem *int_enable_reg = dev_info->mem[0].internal_addr
                                        + DPM_HOST_INT_EN0;
        void __iomem *int_status_reg = dev_info->mem[0].internal_addr
                                        + DPM_HOST_INT_STAT0;

        /* Is one of our interrupts enabled and active ? */
        if (!(ioread32(int_enable_reg) & ioread32(int_status_reg)
                & DPM_HOST_INT_MASK))
                return IRQ_NONE;

        /* Disable interrupt */
        iowrite32(ioread32(int_enable_reg) & ~DPM_HOST_INT_GLOBAL_EN,
                int_enable_reg);
        return IRQ_HANDLED;
}

static int netx_pci_probe(struct pci_dev *dev,
                                        const struct pci_device_id *id)
{
        struct uio_info *info;
        int bar;

        info = devm_kzalloc(&dev->dev, sizeof(struct uio_info), GFP_KERNEL);
        if (!info)
                return -ENOMEM;

        if (pci_enable_device(dev))
                return -ENODEV;

        if (pci_request_regions(dev, "netx"))
                goto out_disable;

        switch (id->device) {
        case PCI_DEVICE_ID_HILSCHER_NETX:
                bar = 0;
                info->name = "netx";
                break;
        case PCI_DEVICE_ID_HILSCHER_NETPLC:
                bar = 0;
                info->name = "netplc";
                break;
        default:
                bar = 2;
                info->name = "netx_plx";
        }

        /* BAR0 or 2 points to the card's dual port memory */
        info->mem[0].addr = pci_resource_start(dev, bar);
        if (!info->mem[0].addr)
                goto out_release;
        info->mem[0].internal_addr = ioremap(pci_resource_start(dev, bar),
                                                pci_resource_len(dev, bar));

        if (!info->mem[0].internal_addr)
                        goto out_release;

        info->mem[0].size = pci_resource_len(dev, bar);
        info->mem[0].memtype = UIO_MEM_PHYS;
        info->irq = dev->irq;
        info->irq_flags = IRQF_SHARED;
        info->handler = netx_handler;
        info->version = "0.0.1";

        /* Make sure all interrupts are disabled */
        iowrite32(0, info->mem[0].internal_addr + DPM_HOST_INT_EN0);

        if (uio_register_device(&dev->dev, info))
                goto out_unmap;

        pci_set_drvdata(dev, info);
        dev_info(&dev->dev, "Found %s card, registered UIO device.\n",
                                info->name);

        return 0;

out_unmap:
        iounmap(info->mem[0].internal_addr);
out_release:
        pci_release_regions(dev);
out_disable:
        pci_disable_device(dev);
        return -ENODEV;
}

static void netx_pci_remove(struct pci_dev *dev)
{
        struct uio_info *info = pci_get_drvdata(dev);

        /* Disable all interrupts */
        iowrite32(0, info->mem[0].internal_addr + DPM_HOST_INT_EN0);
        uio_unregister_device(info);
        pci_release_regions(dev);
        pci_disable_device(dev);
        iounmap(info->mem[0].internal_addr);
}

static const struct pci_device_id netx_pci_ids[] = {
        {
                .vendor =       PCI_VENDOR_ID_HILSCHER,
                .device =       PCI_DEVICE_ID_HILSCHER_NETX,
                .subvendor =    0,
                .subdevice =    0,
        },
        {
                .vendor =       PCI_VENDOR_ID_HILSCHER,
                .device =       PCI_DEVICE_ID_HILSCHER_NETPLC,
                .subvendor =    PCI_VENDOR_ID_HILSCHER,
                .subdevice =    PCI_SUBDEVICE_ID_NETPLC_RAM,
        },
        {
                .vendor =       PCI_VENDOR_ID_HILSCHER,
                .device =       PCI_DEVICE_ID_HILSCHER_NETPLC,
                .subvendor =    PCI_VENDOR_ID_HILSCHER,
                .subdevice =    PCI_SUBDEVICE_ID_NETPLC_FLASH,
        },
        {
                .vendor =       PCI_VENDOR_ID_PLX,
                .device =       PCI_DEVICE_ID_PLX_9030,
                .subvendor =    PCI_VENDOR_ID_PLX,
                .subdevice =    PCI_SUBDEVICE_ID_NXSB_PCA,
        },
        {
                .vendor =       PCI_VENDOR_ID_PLX,
                .device =       PCI_DEVICE_ID_PLX_9030,
                .subvendor =    PCI_VENDOR_ID_PLX,
                .subdevice =    PCI_SUBDEVICE_ID_NXPCA,
        },
        { 0, }
};

static struct pci_driver netx_pci_driver = {
        .name = "netx",
        .id_table = netx_pci_ids,
        .probe = netx_pci_probe,
        .remove = netx_pci_remove,
};

module_pci_driver(netx_pci_driver);
MODULE_DEVICE_TABLE(pci, netx_pci_ids);
MODULE_DESCRIPTION("UIO driver for Hilscher NetX based fieldbus cards");
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Hans J. Koch, Manuel Traut");