1 /* 2 * pci_slot.c - ACPI PCI Slot Driver 3 * 4 * The code here is heavily leveraged from the acpiphp module. 5 * Thanks to Matthew Wilcox <matthew@wil.cx> for much guidance. 6 * Thanks to Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> for code 7 * review and fixes. 8 * 9 * Copyright (C) 2007-2008 Hewlett-Packard Development Company, L.P. 10 * Alex Chiang <achiang@hp.com> 11 * 12 * Copyright (C) 2013 Huawei Tech. Co., Ltd. 13 * Jiang Liu <jiang.liu@huawei.com> 14 * 15 * This program is free software; you can redistribute it and/or modify it 16 * under the terms and conditions of the GNU General Public License, 17 * version 2, as published by the Free Software Foundation. 18 * 19 * This program is distributed in the hope that it will be useful, but 20 * WITHOUT ANY WARRANTY; without even the implied warranty of 21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 22 * General Public License for more details. 23 * 24 * You should have received a copy of the GNU General Public License along 25 * with this program; if not, write to the Free Software Foundation, Inc., 26 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. 27 */ 28 29 #include <linux/kernel.h> 30 #include <linux/module.h> 31 #include <linux/init.h> 32 #include <linux/slab.h> 33 #include <linux/types.h> 34 #include <linux/list.h> 35 #include <linux/pci.h> 36 #include <linux/acpi.h> 37 #include <linux/dmi.h> 38 39 static bool debug; 40 static int check_sta_before_sun; 41 42 #define DRIVER_VERSION "0.1" 43 #define DRIVER_AUTHOR "Alex Chiang <achiang@hp.com>" 44 #define DRIVER_DESC "ACPI PCI Slot Detection Driver" 45 MODULE_AUTHOR(DRIVER_AUTHOR); 46 MODULE_DESCRIPTION(DRIVER_DESC); 47 MODULE_LICENSE("GPL"); 48 MODULE_PARM_DESC(debug, "Debugging mode enabled or not"); 49 module_param(debug, bool, 0644); 50 51 #define _COMPONENT ACPI_PCI_COMPONENT 52 ACPI_MODULE_NAME("pci_slot"); 53 54 #define MY_NAME "pci_slot" 55 #define err(format, arg...) pr_err("%s: " format , MY_NAME , ## arg) 56 #define info(format, arg...) pr_info("%s: " format , MY_NAME , ## arg) 57 #define dbg(format, arg...) \ 58 do { \ 59 if (debug) \ 60 pr_debug("%s: " format, MY_NAME , ## arg); \ 61 } while (0) 62 63 #define SLOT_NAME_SIZE 21 /* Inspired by #define in acpiphp.h */ 64 65 struct acpi_pci_slot { 66 struct pci_slot *pci_slot; /* corresponding pci_slot */ 67 struct list_head list; /* node in the list of slots */ 68 }; 69 70 static LIST_HEAD(slot_list); 71 static DEFINE_MUTEX(slot_list_lock); 72 73 static int 74 check_slot(acpi_handle handle, unsigned long long *sun) 75 { 76 int device = -1; 77 unsigned long long adr, sta; 78 acpi_status status; 79 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 80 81 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer); 82 dbg("Checking slot on path: %s\n", (char *)buffer.pointer); 83 84 if (check_sta_before_sun) { 85 /* If SxFy doesn't have _STA, we just assume it's there */ 86 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta); 87 if (ACPI_SUCCESS(status) && !(sta & ACPI_STA_DEVICE_PRESENT)) 88 goto out; 89 } 90 91 status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr); 92 if (ACPI_FAILURE(status)) { 93 dbg("_ADR returned %d on %s\n", status, (char *)buffer.pointer); 94 goto out; 95 } 96 97 /* No _SUN == not a slot == bail */ 98 status = acpi_evaluate_integer(handle, "_SUN", NULL, sun); 99 if (ACPI_FAILURE(status)) { 100 dbg("_SUN returned %d on %s\n", status, (char *)buffer.pointer); 101 goto out; 102 } 103 104 device = (adr >> 16) & 0xffff; 105 out: 106 kfree(buffer.pointer); 107 return device; 108 } 109 110 /* 111 * Check whether handle has an associated slot and create PCI slot if it has. 112 */ 113 static acpi_status 114 register_slot(acpi_handle handle, u32 lvl, void *context, void **rv) 115 { 116 int device; 117 unsigned long long sun; 118 char name[SLOT_NAME_SIZE]; 119 struct acpi_pci_slot *slot; 120 struct pci_slot *pci_slot; 121 struct pci_bus *pci_bus = context; 122 123 device = check_slot(handle, &sun); 124 if (device < 0) 125 return AE_OK; 126 127 /* 128 * There may be multiple PCI functions associated with the same slot. 129 * Check whether PCI slot has already been created for this PCI device. 130 */ 131 list_for_each_entry(slot, &slot_list, list) { 132 pci_slot = slot->pci_slot; 133 if (pci_slot->bus == pci_bus && pci_slot->number == device) 134 return AE_OK; 135 } 136 137 slot = kmalloc(sizeof(*slot), GFP_KERNEL); 138 if (!slot) { 139 err("%s: cannot allocate memory\n", __func__); 140 return AE_OK; 141 } 142 143 snprintf(name, sizeof(name), "%llu", sun); 144 pci_slot = pci_create_slot(pci_bus, device, name, NULL); 145 if (IS_ERR(pci_slot)) { 146 err("pci_create_slot returned %ld\n", PTR_ERR(pci_slot)); 147 kfree(slot); 148 return AE_OK; 149 } 150 151 slot->pci_slot = pci_slot; 152 list_add(&slot->list, &slot_list); 153 154 get_device(&pci_bus->dev); 155 156 dbg("pci_slot: %p, pci_bus: %x, device: %d, name: %s\n", 157 pci_slot, pci_bus->number, device, name); 158 159 return AE_OK; 160 } 161 162 void acpi_pci_slot_enumerate(struct pci_bus *bus, acpi_handle handle) 163 { 164 mutex_lock(&slot_list_lock); 165 acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1, 166 register_slot, NULL, bus, NULL); 167 mutex_unlock(&slot_list_lock); 168 } 169 170 void acpi_pci_slot_remove(struct pci_bus *bus) 171 { 172 struct acpi_pci_slot *slot, *tmp; 173 174 mutex_lock(&slot_list_lock); 175 list_for_each_entry_safe(slot, tmp, &slot_list, list) { 176 if (slot->pci_slot->bus == bus) { 177 list_del(&slot->list); 178 pci_destroy_slot(slot->pci_slot); 179 put_device(&bus->dev); 180 kfree(slot); 181 } 182 } 183 mutex_unlock(&slot_list_lock); 184 } 185 186 static int do_sta_before_sun(const struct dmi_system_id *d) 187 { 188 info("%s detected: will evaluate _STA before calling _SUN\n", d->ident); 189 check_sta_before_sun = 1; 190 return 0; 191 } 192 193 static struct dmi_system_id acpi_pci_slot_dmi_table[] __initdata = { 194 /* 195 * Fujitsu Primequest machines will return 1023 to indicate an 196 * error if the _SUN method is evaluated on SxFy objects that 197 * are not present (as indicated by _STA), so for those machines, 198 * we want to check _STA before evaluating _SUN. 199 */ 200 { 201 .callback = do_sta_before_sun, 202 .ident = "Fujitsu PRIMEQUEST", 203 .matches = { 204 DMI_MATCH(DMI_BIOS_VENDOR, "FUJITSU LIMITED"), 205 DMI_MATCH(DMI_BIOS_VERSION, "PRIMEQUEST"), 206 }, 207 }, 208 {} 209 }; 210 211 void __init acpi_pci_slot_init(void) 212 { 213 dmi_check_system(acpi_pci_slot_dmi_table); 214 } 215