/*
* pci_slot.c - ACPI PCI Slot Driver
*
* The code here is heavily leveraged from the acpiphp module.
* Thanks to Matthew Wilcox <matthew@wil.cx> for much guidance.
* Thanks to Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> for code
* review and fixes.
*
* Copyright (C) 2007-2008 Hewlett-Packard Development Company, L.P.
* Alex Chiang <achiang@hp.com>
*
* Copyright (C) 2013 Huawei Tech. Co., Ltd.
* Jiang Liu <jiang.liu@huawei.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/list.h>
#include <linux/pci.h>
#include <linux/acpi.h>
#include <linux/dmi.h>
static bool debug;
static int check_sta_before_sun;
#define DRIVER_VERSION "0.1"
#define DRIVER_AUTHOR "Alex Chiang <achiang@hp.com>"
#define DRIVER_DESC "ACPI PCI Slot Detection Driver"
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
module_param(debug, bool, 0644);
#define _COMPONENT ACPI_PCI_COMPONENT
ACPI_MODULE_NAME("pci_slot");
#define MY_NAME "pci_slot"
#define err(format, arg...) pr_err("%s: " format , MY_NAME , ## arg)
#define info(format, arg...) pr_info("%s: " format , MY_NAME , ## arg)
#define dbg(format, arg...) \
do { \
if (debug) \
pr_debug("%s: " format, MY_NAME , ## arg); \
} while (0)
#define SLOT_NAME_SIZE 21 /* Inspired by #define in acpiphp.h */
struct acpi_pci_slot {
struct pci_slot *pci_slot; /* corresponding pci_slot */
struct list_head list; /* node in the list of slots */
};
static LIST_HEAD(slot_list);
static DEFINE_MUTEX(slot_list_lock);
static int
check_slot(acpi_handle handle, unsigned long long *sun)
{
int device = -1;
unsigned long long adr, sta;
acpi_status status;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
dbg("Checking slot on path: %s\n", (char *)buffer.pointer);
if (check_sta_before_sun) {
/* If SxFy doesn't have _STA, we just assume it's there */
status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
if (ACPI_SUCCESS(status) && !(sta & ACPI_STA_DEVICE_PRESENT))
goto out;
}
status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr);
if (ACPI_FAILURE(status)) {
dbg("_ADR returned %d on %s\n", status, (char *)buffer.pointer);
goto out;
}
/* No _SUN == not a slot == bail */
status = acpi_evaluate_integer(handle, "_SUN", NULL, sun);
if (ACPI_FAILURE(status)) {
dbg("_SUN returned %d on %s\n", status, (char *)buffer.pointer);
goto out;
}
device = (adr >> 16) & 0xffff;
out:
kfree(buffer.pointer);
return device;
}
/*
* Check whether handle has an associated slot and create PCI slot if it has.
*/
static acpi_status
register_slot(acpi_handle handle, u32 lvl, void *context, void **rv)
{
int device;
unsigned long long sun;
char name[SLOT_NAME_SIZE];
struct acpi_pci_slot *slot;
struct pci_slot *pci_slot;
struct pci_bus *pci_bus = context;
device = check_slot(handle, &sun);
if (device < 0)
return AE_OK;
/*
* There may be multiple PCI functions associated with the same slot.
* Check whether PCI slot has already been created for this PCI device.
*/
list_for_each_entry(slot, &slot_list, list) {
pci_slot = slot->pci_slot;
if (pci_slot->bus == pci_bus && pci_slot->number == device)
return AE_OK;
}
slot = kmalloc(sizeof(*slot), GFP_KERNEL);
if (!slot) {
err("%s: cannot allocate memory\n", __func__);
return AE_OK;
}
snprintf(name, sizeof(name), "%llu", sun);
pci_slot = pci_create_slot(pci_bus, device, name, NULL);
if (IS_ERR(pci_slot)) {
err("pci_create_slot returned %ld\n", PTR_ERR(pci_slot));
kfree(slot);
return AE_OK;
}
slot->pci_slot = pci_slot;
list_add(&slot->list, &slot_list);
get_device(&pci_bus->dev);
dbg("pci_slot: %p, pci_bus: %x, device: %d, name: %s\n",
pci_slot, pci_bus->number, device, name);
return AE_OK;
}
void acpi_pci_slot_enumerate(struct pci_bus *bus)
{
acpi_handle handle = ACPI_HANDLE(bus->bridge);
if (handle) {
mutex_lock(&slot_list_lock);
acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
register_slot, NULL, bus, NULL);
mutex_unlock(&slot_list_lock);
}
}
void acpi_pci_slot_remove(struct pci_bus *bus)
{
struct acpi_pci_slot *slot, *tmp;
mutex_lock(&slot_list_lock);
list_for_each_entry_safe(slot, tmp, &slot_list, list) {
if (slot->pci_slot->bus == bus) {
list_del(&slot->list);
pci_destroy_slot(slot->pci_slot);
put_device(&bus->dev);
kfree(slot);
}
}
mutex_unlock(&slot_list_lock);
}
static int do_sta_before_sun(const struct dmi_system_id *d)
{
info("%s detected: will evaluate _STA before calling _SUN\n", d->ident);
check_sta_before_sun = 1;
return 0;
}
static struct dmi_system_id acpi_pci_slot_dmi_table[] __initdata = {
/*
* Fujitsu Primequest machines will return 1023 to indicate an
* error if the _SUN method is evaluated on SxFy objects that
* are not present (as indicated by _STA), so for those machines,
* we want to check _STA before evaluating _SUN.
*/
{
.callback = do_sta_before_sun,
.ident = "Fujitsu PRIMEQUEST",
.matches = {
DMI_MATCH(DMI_BIOS_VENDOR, "FUJITSU LIMITED"),
DMI_MATCH(DMI_BIOS_VERSION, "PRIMEQUEST"),
},
},
{}
};
void __init acpi_pci_slot_init(void)
{
dmi_check_system(acpi_pci_slot_dmi_table);
}
