drivers/pci/hotplug/rpaphp_slot.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * RPA Virtual I/O device functions
   4  * Copyright (C) 2004 Linda Xie <lxie@us.ibm.com>
   5  *
   6  * All rights reserved.
   7  *
   8  * Send feedback to <lxie@us.ibm.com>
   9  *
  10  */
  11 #include <linux/kernel.h>
  12 #include <linux/module.h>
  13 #include <linux/sysfs.h>
  14 #include <linux/pci.h>
  15 #include <linux/string.h>
  16 #include <linux/slab.h>
  17
  18 #include <asm/rtas.h>
  19 #include "rpaphp.h"
  20
  21 /* free up the memory used by a slot */
  22 void dealloc_slot_struct(struct slot *slot)
  23 {
  24         of_node_put(slot->dn);
  25         kfree(slot->name);
  26         kfree(slot);
  27 }
  28
  29 struct slot *alloc_slot_struct(struct device_node *dn,
  30                 int drc_index, char *drc_name, int power_domain)
  31 {
  32         struct slot *slot;
  33
  34         slot = kzalloc(sizeof(struct slot), GFP_KERNEL);
  35         if (!slot)
  36                 goto error_nomem;
  37         slot->name = kstrdup(drc_name, GFP_KERNEL);
  38         if (!slot->name)
  39                 goto error_slot;
  40         slot->dn = of_node_get(dn);
  41         slot->index = drc_index;
  42         slot->power_domain = power_domain;
  43         slot->hotplug_slot.ops = &rpaphp_hotplug_slot_ops;
  44
  45         return (slot);
  46
  47 error_slot:
  48         kfree(slot);
  49 error_nomem:
  50         return NULL;
  51 }
  52
  53 static int is_registered(struct slot *slot)
  54 {
  55         struct slot *tmp_slot;
  56
  57         list_for_each_entry(tmp_slot, &rpaphp_slot_head, rpaphp_slot_list) {
  58                 if (!strcmp(tmp_slot->name, slot->name))
  59                         return 1;
  60         }
  61         return 0;
  62 }
  63
  64 int rpaphp_deregister_slot(struct slot *slot)
  65 {
  66         int retval = 0;
  67         struct hotplug_slot *php_slot = &slot->hotplug_slot;
  68
  69          dbg("%s - Entry: deregistering slot=%s\n",
  70                 __func__, slot->name);
  71
  72         list_del(&slot->rpaphp_slot_list);
  73         pci_hp_deregister(php_slot);
  74         dealloc_slot_struct(slot);
  75
  76         dbg("%s - Exit: rc[%d]\n", __func__, retval);
  77         return retval;
  78 }
  79 EXPORT_SYMBOL_GPL(rpaphp_deregister_slot);
  80
  81 int rpaphp_register_slot(struct slot *slot)
  82 {
  83         struct hotplug_slot *php_slot = &slot->hotplug_slot;
  84         struct device_node *child;
  85         u32 my_index;
  86         int retval;
  87         int slotno = -1;
  88
  89         dbg("%s registering slot:path[%pOF] index[%x], name[%s] pdomain[%x] type[%d]\n",
  90                 __func__, slot->dn, slot->index, slot->name,
  91                 slot->power_domain, slot->type);
  92
  93         /* should not try to register the same slot twice */
  94         if (is_registered(slot)) {
  95                 err("rpaphp_register_slot: slot[%s] is already registered\n", slot->name);
  96                 return -EAGAIN;
  97         }
  98
  99         for_each_child_of_node(slot->dn, child) {
 100                 retval = of_property_read_u32(child, "ibm,my-drc-index", &my_index);
 101                 if (my_index == slot->index) {
 102                         slotno = PCI_SLOT(PCI_DN(child)->devfn);
 103                         of_node_put(child);
 104                         break;
 105                 }
 106         }
 107
 108         retval = pci_hp_register(php_slot, slot->bus, slotno, slot->name);
 109         if (retval) {
 110                 err("pci_hp_register failed with error %d\n", retval);
 111                 return retval;
 112         }
 113
 114         /* add slot to our internal list */
 115         list_add(&slot->rpaphp_slot_list, &rpaphp_slot_head);
 116         info("Slot [%s] registered\n", slot->name);
 117         return 0;
 118 }