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