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 static void rpaphp_release_slot(struct hotplug_slot *hotplug_slot)
  23 {
  24         struct slot *slot = (struct slot *) hotplug_slot->private;
  25         dealloc_slot_struct(slot);
  26 }
  27
  28 void dealloc_slot_struct(struct slot *slot)
  29 {
  30         kfree(slot->hotplug_slot->info);
  31         kfree(slot->name);
  32         kfree(slot->hotplug_slot);
  33         kfree(slot);
  34 }
  35
  36 struct slot *alloc_slot_struct(struct device_node *dn,
  37                 int drc_index, char *drc_name, int power_domain)
  38 {
  39         struct slot *slot;
  40
  41         slot = kzalloc(sizeof(struct slot), GFP_KERNEL);
  42         if (!slot)
  43                 goto error_nomem;
  44         slot->hotplug_slot = kzalloc(sizeof(struct hotplug_slot), GFP_KERNEL);
  45         if (!slot->hotplug_slot)
  46                 goto error_slot;
  47         slot->hotplug_slot->info = kzalloc(sizeof(struct hotplug_slot_info),
  48                                            GFP_KERNEL);
  49         if (!slot->hotplug_slot->info)
  50                 goto error_hpslot;
  51         slot->name = kstrdup(drc_name, GFP_KERNEL);
  52         if (!slot->name)
  53                 goto error_info;
  54         slot->dn = dn;
  55         slot->index = drc_index;
  56         slot->power_domain = power_domain;
  57         slot->hotplug_slot->private = slot;
  58         slot->hotplug_slot->ops = &rpaphp_hotplug_slot_ops;
  59         slot->hotplug_slot->release = &rpaphp_release_slot;
  60
  61         return (slot);
  62
  63 error_info:
  64         kfree(slot->hotplug_slot->info);
  65 error_hpslot:
  66         kfree(slot->hotplug_slot);
  67 error_slot:
  68         kfree(slot);
  69 error_nomem:
  70         return NULL;
  71 }
  72
  73 static int is_registered(struct slot *slot)
  74 {
  75         struct slot *tmp_slot;
  76
  77         list_for_each_entry(tmp_slot, &rpaphp_slot_head, rpaphp_slot_list) {
  78                 if (!strcmp(tmp_slot->name, slot->name))
  79                         return 1;
  80         }
  81         return 0;
  82 }
  83
  84 int rpaphp_deregister_slot(struct slot *slot)
  85 {
  86         int retval = 0;
  87         struct hotplug_slot *php_slot = slot->hotplug_slot;
  88
  89          dbg("%s - Entry: deregistering slot=%s\n",
  90                 __func__, slot->name);
  91
  92         list_del(&slot->rpaphp_slot_list);
  93
  94         retval = pci_hp_deregister(php_slot);
  95         if (retval)
  96                 err("Problem unregistering a slot %s\n", slot->name);
  97
  98         dbg("%s - Exit: rc[%d]\n", __func__, retval);
  99         return retval;
 100 }
 101 EXPORT_SYMBOL_GPL(rpaphp_deregister_slot);
 102
 103 int rpaphp_register_slot(struct slot *slot)
 104 {
 105         struct hotplug_slot *php_slot = slot->hotplug_slot;
 106         struct device_node *child;
 107         u32 my_index;
 108         int retval;
 109         int slotno = -1;
 110
 111         dbg("%s registering slot:path[%pOF] index[%x], name[%s] pdomain[%x] type[%d]\n",
 112                 __func__, slot->dn, slot->index, slot->name,
 113                 slot->power_domain, slot->type);
 114
 115         /* should not try to register the same slot twice */
 116         if (is_registered(slot)) {
 117                 err("rpaphp_register_slot: slot[%s] is already registered\n", slot->name);
 118                 return -EAGAIN;
 119         }
 120
 121         for_each_child_of_node(slot->dn, child) {
 122                 retval = of_property_read_u32(child, "ibm,my-drc-index", &my_index);
 123                 if (my_index == slot->index) {
 124                         slotno = PCI_SLOT(PCI_DN(child)->devfn);
 125                         of_node_put(child);
 126                         break;
 127                 }
 128         }
 129
 130         retval = pci_hp_register(php_slot, slot->bus, slotno, slot->name);
 131         if (retval) {
 132                 err("pci_hp_register failed with error %d\n", retval);
 133                 return retval;
 134         }
 135
 136         /* add slot to our internal list */
 137         list_add(&slot->rpaphp_slot_list, &rpaphp_slot_head);
 138         info("Slot [%s] registered\n", slot->name);
 139         return 0;
 140 }