[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>
diff --git a/drivers/pci/hotplug/acpiphp_dock.c b/drivers/pci/hotplug/acpiphp_dock.c
new file mode 100644
index 0000000..4f1aaf1
--- /dev/null
+++ b/drivers/pci/hotplug/acpiphp_dock.c
@@ -0,0 +1,438 @@
+/*
+ * 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);
+ }
+}
+
+