root/arch/powerpc/platforms/pasemi/misc.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2007 PA Semi, Inc
 *
 * Parts based on arch/powerpc/sysdev/fsl_soc.c:
 *
 * 2006 (c) MontaVista Software, Inc.
 */

#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/i2c.h>

#ifdef CONFIG_I2C_BOARDINFO
/* The below is from fsl_soc.c.  It's copied because since there are no
 * official bus bindings at this time it doesn't make sense to share across
 * the platforms, even though they happen to be common.
 */
struct i2c_driver_device {
        char    *of_device;
        char    *i2c_type;
};

static struct i2c_driver_device i2c_devices[] __initdata = {
        {"dallas,ds1338",  "ds1338"},
};

static int __init find_i2c_driver(struct device_node *node,
                                     struct i2c_board_info *info)
{
        int i;

        for (i = 0; i < ARRAY_SIZE(i2c_devices); i++) {
                if (!of_device_is_compatible(node, i2c_devices[i].of_device))
                        continue;
                if (strscpy(info->type, i2c_devices[i].i2c_type, I2C_NAME_SIZE) < 0)
                        return -ENOMEM;
                return 0;
        }
        return -ENODEV;
}

static int __init pasemi_register_i2c_devices(void)
{
        struct pci_dev *pdev;
        struct device_node *adap_node;
        struct device_node *node;

        pdev = NULL;
        while ((pdev = pci_get_device(PCI_VENDOR_ID_PASEMI, 0xa003, pdev))) {
                adap_node = pci_device_to_OF_node(pdev);

                if (!adap_node)
                        continue;

                for_each_child_of_node(adap_node, node) {
                        struct i2c_board_info info = {};
                        const u32 *addr;
                        int len;

                        addr = of_get_property(node, "reg", &len);
                        if (!addr || len < sizeof(int) ||
                            *addr > (1 << 10) - 1) {
                                pr_warn("pasemi_register_i2c_devices: invalid i2c device entry\n");
                                continue;
                        }

                        info.irq = irq_of_parse_and_map(node, 0);
                        if (!info.irq)
                                info.irq = -1;

                        if (find_i2c_driver(node, &info) < 0)
                                continue;

                        info.addr = *addr;

                        i2c_register_board_info(PCI_FUNC(pdev->devfn), &info,
                                                1);
                }
        }
        return 0;
}
device_initcall(pasemi_register_i2c_devices);
#endif