// SPDX-License-Identifier: GPL-2.0-only
/*
 * CE4100 PCI-I2C glue code for PXA's driver
 * Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 *
 * The CE4100's I2C device is more or less the same one as found on PXA.
 * It does not support target mode, the register slightly moved. This PCI
 * device provides three bars, every contains a single I2C controller.
 */
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/platform_device.h>
#include <linux/platform_data/i2c-pxa.h>
#include <linux/of.h>
#include <linux/of_address.h>

#define CE4100_PCI_I2C_DEVS     3

struct ce4100_devices {
        struct platform_device *pdev[CE4100_PCI_I2C_DEVS];
};

static struct platform_device *add_i2c_device(struct pci_dev *dev, int bar)
{
        struct platform_device *pdev;
        struct i2c_pxa_platform_data pdata;
        struct resource res[2];
        struct device_node *child;
        static int devnum;
        int ret;

        memset(&pdata, 0, sizeof(struct i2c_pxa_platform_data));
        memset(&res, 0, sizeof(res));

        res[0].flags = IORESOURCE_MEM;
        res[0].start = pci_resource_start(dev, bar);
        res[0].end = pci_resource_end(dev, bar);

        res[1].flags = IORESOURCE_IRQ;
        res[1].start = dev->irq;
        res[1].end = dev->irq;

        for_each_child_of_node(dev->dev.of_node, child) {
                const void *prop;
                struct resource r;
                int ret;

                ret = of_address_to_resource(child, 0, &r);
                if (ret < 0)
                        continue;
                if (r.start != res[0].start)
                        continue;
                if (r.end != res[0].end)
                        continue;
                if (r.flags != res[0].flags)
                        continue;

                prop = of_get_property(child, "fast-mode", NULL);
                if (prop)
                        pdata.fast_mode = 1;

                break;
        }

        if (!child) {
                dev_err(&dev->dev, "failed to match a DT node for bar %d.\n",
                                bar);
                ret = -EINVAL;
                goto out;
        }

        pdev = platform_device_alloc("ce4100-i2c", devnum);
        if (!pdev) {
                of_node_put(child);
                ret = -ENOMEM;
                goto out;
        }
        pdev->dev.parent = &dev->dev;
        pdev->dev.of_node = child;

        ret = platform_device_add_resources(pdev, res, ARRAY_SIZE(res));
        if (ret)
                goto err;

        ret = platform_device_add_data(pdev, &pdata, sizeof(pdata));
        if (ret)
                goto err;

        ret = platform_device_add(pdev);
        if (ret)
                goto err;
        devnum++;
        return pdev;
err:
        platform_device_put(pdev);
out:
        return ERR_PTR(ret);
}

static int ce4100_i2c_probe(struct pci_dev *dev,
                const struct pci_device_id *ent)
{
        int ret;
        int i;
        struct ce4100_devices *sds;

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

        if (!dev->dev.of_node) {
                dev_err(&dev->dev, "Missing device tree node.\n");
                return -EINVAL;
        }
        sds = kzalloc_obj(*sds);
        if (!sds)
                return -ENOMEM;

        for (i = 0; i < ARRAY_SIZE(sds->pdev); i++) {
                sds->pdev[i] = add_i2c_device(dev, i);
                if (IS_ERR(sds->pdev[i])) {
                        ret = PTR_ERR(sds->pdev[i]);
                        while (--i >= 0)
                                platform_device_unregister(sds->pdev[i]);
                        goto err_dev_add;
                }
        }
        pci_set_drvdata(dev, sds);
        return 0;

err_dev_add:
        kfree(sds);
        return ret;
}

static const struct pci_device_id ce4100_i2c_devices[] = {
        { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2e68)},
        { }
};

static struct pci_driver ce4100_i2c_driver = {
        .driver = {
                .suppress_bind_attrs = true,
        },
        .name           = "ce4100_i2c",
        .id_table       = ce4100_i2c_devices,
        .probe          = ce4100_i2c_probe,
};
builtin_pci_driver(ce4100_i2c_driver);