linux/drivers/pci/hotplug/acpiphp_dock.c
Kristen Accardi 20416ea540 [PATCH] acpiphp: add dock event handling
These patches add generic dock event handling to acpiphp.  If there are
pci devices that need to be inserted/removed after the dock event, the
event notification will be handed down to the normal pci hotplug event
handler in acpiphp so that new bridges/devices can be enumerated.

Because some dock stations do not have pci bridges or pci devices that
need to be inserted after a dock, acpiphp will remain loaded to handle
dock events even if no hotpluggable pci slots are discovered.

You probably need to have the pci=assign-busses kernel parameter enabled
to use these patches, and you may not allow ibm_acpi to handle docking
notifications and use this patch.

This patch incorporates feedback provided by many.

Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-23 14:35:15 -08:00

439 lines
8.9 KiB
C

/*
* ACPI PCI HotPlug dock functions to ACPI CA subsystem
*
* Copyright (C) 2006 Kristen Carlson Accardi (kristen.c.accardi@intel.com)
* Copyright (C) 2006 Intel Corporation
*
* All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*
* 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, GOOD TITLE or
* NON INFRINGEMENT. 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* Send feedback to <kristen.c.accardi@intel.com>
*
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/smp_lock.h>
#include <linux/mutex.h>
#include "../pci.h"
#include "pci_hotplug.h"
#include "acpiphp.h"
static struct acpiphp_dock_station *ds;
#define MY_NAME "acpiphp_dock"
int is_dependent_device(acpi_handle handle)
{
return (get_dependent_device(handle) ? 1 : 0);
}
static acpi_status
find_dependent_device(acpi_handle handle, u32 lvl, void *context, void **rv)
{
int *count = (int *)context;
if (is_dependent_device(handle)) {
(*count)++;
return AE_CTRL_TERMINATE;
} else {
return AE_OK;
}
}
void add_dependent_device(struct dependent_device *new_dd)
{
list_add_tail(&new_dd->device_list, &ds->dependent_devices);
}
void add_pci_dependent_device(struct dependent_device *new_dd)
{
list_add_tail(&new_dd->pci_list, &ds->pci_dependent_devices);
}
struct dependent_device * get_dependent_device(acpi_handle handle)
{
struct dependent_device *dd;
if (!ds)
return NULL;
list_for_each_entry(dd, &ds->dependent_devices, device_list) {
if (handle == dd->handle)
return dd;
}
return NULL;
}
struct dependent_device *alloc_dependent_device(acpi_handle handle)
{
struct dependent_device *dd;
dd = kzalloc(sizeof(*dd), GFP_KERNEL);
if (dd) {
INIT_LIST_HEAD(&dd->pci_list);
INIT_LIST_HEAD(&dd->device_list);
dd->handle = handle;
}
return dd;
}
static int is_dock(acpi_handle handle)
{
acpi_status status;
acpi_handle tmp;
status = acpi_get_handle(handle, "_DCK", &tmp);
if (ACPI_FAILURE(status)) {
return 0;
}
return 1;
}
static int dock_present(void)
{
unsigned long sta;
acpi_status status;
if (ds) {
status = acpi_evaluate_integer(ds->handle, "_STA", NULL, &sta);
if (ACPI_SUCCESS(status) && sta)
return 1;
}
return 0;
}
static void eject_dock(void)
{
struct acpi_object_list arg_list;
union acpi_object arg;
arg_list.count = 1;
arg_list.pointer = &arg;
arg.type = ACPI_TYPE_INTEGER;
arg.integer.value = 1;
if (ACPI_FAILURE(acpi_evaluate_object(ds->handle, "_EJ0",
&arg_list, NULL)) || dock_present())
warn("%s: failed to eject dock!\n", __FUNCTION__);
return;
}
static acpi_status handle_dock(int dock)
{
acpi_status status;
struct acpi_object_list arg_list;
union acpi_object arg;
struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
dbg("%s: %s\n", __FUNCTION__, dock ? "docking" : "undocking");
/* _DCK method has one argument */
arg_list.count = 1;
arg_list.pointer = &arg;
arg.type = ACPI_TYPE_INTEGER;
arg.integer.value = dock;
status = acpi_evaluate_object(ds->handle, "_DCK",
&arg_list, &buffer);
if (ACPI_FAILURE(status))
err("%s: failed to execute _DCK\n", __FUNCTION__);
acpi_os_free(buffer.pointer);
return status;
}
static inline void dock(void)
{
handle_dock(1);
}
static inline void undock(void)
{
handle_dock(0);
}
/*
* the _DCK method can do funny things... and sometimes not
* hah-hah funny.
*
* TBD - figure out a way to only call fixups for
* systems that require them.
*/
static void post_dock_fixups(void)
{
struct pci_bus *bus;
u32 buses;
struct dependent_device *dd;
list_for_each_entry(dd, &ds->pci_dependent_devices, pci_list) {
bus = dd->func->slot->bridge->pci_bus;
/* fixup bad _DCK function that rewrites
* secondary bridge on slot
*/
pci_read_config_dword(bus->self,
PCI_PRIMARY_BUS,
&buses);
if (((buses >> 8) & 0xff) != bus->secondary) {
buses = (buses & 0xff000000)
| ((unsigned int)(bus->primary) << 0)
| ((unsigned int)(bus->secondary) << 8)
| ((unsigned int)(bus->subordinate) << 16);
pci_write_config_dword(bus->self,
PCI_PRIMARY_BUS,
buses);
}
}
}
static void hotplug_pci(u32 type)
{
struct dependent_device *dd;
list_for_each_entry(dd, &ds->pci_dependent_devices, pci_list)
handle_hotplug_event_func(dd->handle, type, dd->func);
}
static inline void begin_dock(void)
{
ds->flags |= DOCK_DOCKING;
}
static inline void complete_dock(void)
{
ds->flags &= ~(DOCK_DOCKING);
ds->last_dock_time = jiffies;
}
static int dock_in_progress(void)
{
if (ds->flags & DOCK_DOCKING ||
ds->last_dock_time == jiffies) {
dbg("dock in progress\n");
return 1;
}
return 0;
}
static void
handle_hotplug_event_dock(acpi_handle handle, u32 type, void *context)
{
dbg("%s: enter\n", __FUNCTION__);
switch (type) {
case ACPI_NOTIFY_BUS_CHECK:
dbg("BUS Check\n");
if (!dock_in_progress() && dock_present()) {
begin_dock();
dock();
if (!dock_present()) {
err("Unable to dock!\n");
break;
}
post_dock_fixups();
hotplug_pci(type);
complete_dock();
}
break;
case ACPI_NOTIFY_EJECT_REQUEST:
dbg("EJECT request\n");
if (!dock_in_progress() && dock_present()) {
hotplug_pci(type);
undock();
eject_dock();
if (dock_present())
err("Unable to undock!\n");
}
break;
}
}
static acpi_status
find_dock_ejd(acpi_handle handle, u32 lvl, void *context, void **rv)
{
acpi_status status;
acpi_handle tmp;
acpi_handle dck_handle = (acpi_handle) context;
char objname[64];
struct acpi_buffer buffer = { .length = sizeof(objname),
.pointer = objname };
struct acpi_buffer ejd_buffer = {ACPI_ALLOCATE_BUFFER, NULL};
union acpi_object *ejd_obj;
status = acpi_get_handle(handle, "_EJD", &tmp);
if (ACPI_FAILURE(status))
return AE_OK;
/* make sure we are dependent on the dock device,
* by executing the _EJD method, then getting a handle
* to the device referenced by that name. If that
* device handle is the same handle as the dock station
* handle, then we are a device dependent on the dock station
*/
acpi_get_name(dck_handle, ACPI_FULL_PATHNAME, &buffer);
status = acpi_evaluate_object(handle, "_EJD", NULL, &ejd_buffer);
if (ACPI_FAILURE(status)) {
err("Unable to execute _EJD!\n");
goto find_ejd_out;
}
ejd_obj = ejd_buffer.pointer;
status = acpi_get_handle(NULL, ejd_obj->string.pointer, &tmp);
if (ACPI_FAILURE(status))
goto find_ejd_out;
if (tmp == dck_handle) {
struct dependent_device *dd;
dbg("%s: found device dependent on dock\n", __FUNCTION__);
dd = alloc_dependent_device(handle);
if (!dd) {
err("Can't allocate memory for dependent device!\n");
goto find_ejd_out;
}
add_dependent_device(dd);
}
find_ejd_out:
acpi_os_free(ejd_buffer.pointer);
return AE_OK;
}
int detect_dependent_devices(acpi_handle *bridge_handle)
{
acpi_status status;
int count;
count = 0;
status = acpi_walk_namespace(ACPI_TYPE_DEVICE, bridge_handle,
(u32)1, find_dependent_device,
(void *)&count, NULL);
return count;
}
static acpi_status
find_dock(acpi_handle handle, u32 lvl, void *context, void **rv)
{
int *count = (int *)context;
if (is_dock(handle)) {
dbg("%s: found dock\n", __FUNCTION__);
ds = kzalloc(sizeof(*ds), GFP_KERNEL);
ds->handle = handle;
INIT_LIST_HEAD(&ds->dependent_devices);
INIT_LIST_HEAD(&ds->pci_dependent_devices);
/* look for devices dependent on dock station */
acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
ACPI_UINT32_MAX, find_dock_ejd, handle, NULL);
acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
handle_hotplug_event_dock, ds);
(*count)++;
}
return AE_OK;
}
int find_dock_station(void)
{
int num = 0;
ds = NULL;
/* start from the root object, because some laptops define
* _DCK methods outside the scope of PCI (IBM x-series laptop)
*/
acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
ACPI_UINT32_MAX, find_dock, &num, NULL);
return num;
}
void remove_dock_station(void)
{
struct dependent_device *dd, *tmp;
if (ds) {
if (ACPI_FAILURE(acpi_remove_notify_handler(ds->handle,
ACPI_SYSTEM_NOTIFY, handle_hotplug_event_dock)))
err("failed to remove dock notify handler\n");
/* free all dependent devices */
list_for_each_entry_safe(dd, tmp, &ds->dependent_devices,
device_list)
kfree(dd);
/* no need to touch the pci_dependent_device list,
* cause all memory was freed above
*/
kfree(ds);
}
}