// SPDX-License-Identifier: GPL-2.0+
/*
 * RPA Virtual I/O device functions
 * Copyright (C) 2004 Linda Xie <lxie@us.ibm.com>
 *
 * All rights reserved.
 *
 * Send feedback to <lxie@us.ibm.com>
 *
 */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/sysfs.h>
#include <linux/of.h>
#include <linux/pci.h>
#include <linux/string.h>
#include <linux/slab.h>

#include <asm/rtas.h>
#include "rpaphp.h"

/* free up the memory used by a slot */
void dealloc_slot_struct(struct slot *slot)
{
        of_node_put(slot->dn);
        kfree(slot->name);
        kfree(slot);
}

struct slot *alloc_slot_struct(struct device_node *dn,
                int drc_index, char *drc_name, int power_domain)
{
        struct slot *slot;

        slot = kzalloc_obj(struct slot);
        if (!slot)
                goto error_nomem;
        slot->name = kstrdup(drc_name, GFP_KERNEL);
        if (!slot->name)
                goto error_slot;
        slot->dn = of_node_get(dn);
        slot->index = drc_index;
        slot->power_domain = power_domain;
        slot->hotplug_slot.ops = &rpaphp_hotplug_slot_ops;

        return (slot);

error_slot:
        kfree(slot);
error_nomem:
        return NULL;
}

static int is_registered(struct slot *slot)
{
        struct slot *tmp_slot;

        list_for_each_entry(tmp_slot, &rpaphp_slot_head, rpaphp_slot_list) {
                if (!strcmp(tmp_slot->name, slot->name))
                        return 1;
        }
        return 0;
}

int rpaphp_deregister_slot(struct slot *slot)
{
        int retval = 0;
        struct hotplug_slot *php_slot = &slot->hotplug_slot;

         dbg("%s - Entry: deregistering slot=%s\n",
                __func__, slot->name);

        list_del(&slot->rpaphp_slot_list);
        pci_hp_deregister(php_slot);
        dealloc_slot_struct(slot);

        dbg("%s - Exit: rc[%d]\n", __func__, retval);
        return retval;
}
EXPORT_SYMBOL_GPL(rpaphp_deregister_slot);

int rpaphp_register_slot(struct slot *slot)
{
        struct hotplug_slot *php_slot = &slot->hotplug_slot;
        struct device_node *child;
        u32 my_index;
        int retval;
        int slotno = -1;

        dbg("%s registering slot:path[%pOF] index[%x], name[%s] pdomain[%x] type[%d]\n",
                __func__, slot->dn, slot->index, slot->name,
                slot->power_domain, slot->type);

        /* should not try to register the same slot twice */
        if (is_registered(slot)) {
                err("rpaphp_register_slot: slot[%s] is already registered\n", slot->name);
                return -EAGAIN;
        }

        for_each_child_of_node(slot->dn, child) {
                retval = of_property_read_u32(child, "ibm,my-drc-index", &my_index);
                if (my_index == slot->index) {
                        slotno = PCI_SLOT(PCI_DN(child)->devfn);
                        of_node_put(child);
                        break;
                }
        }

        retval = pci_hp_register(php_slot, slot->bus, slotno, slot->name);
        if (retval) {
                err("pci_hp_register failed with error %d\n", retval);
                return retval;
        }

        /* add slot to our internal list */
        list_add(&slot->rpaphp_slot_list, &rpaphp_slot_head);
        info("Slot [%s] registered\n", slot->name);
        return 0;
}