[PATCH 3/3] ACPI: WMI: Enable event methods when registering notifiers

Carlos Corbacho
2008-10-08T20:40:41Z

From: Matthew Garrett <mjg@redhat.com>

According to the ACPI-WMI spec, event blocks may provide a function call
for enabling/disabling them. This patch adds support for making these
calls when registering or removing notifications. Without this, my Dell
firmware provides no data in the event notification.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Carlos Corbacho <carlos@strangeworlds.co.uk>
---

drivers/acpi/wmi.c | 39 +++++++++++++++++++++++++++++++++++++--
1 files changed, 37 insertions(+), 2 deletions(-)

diff --git a/drivers/acpi/wmi.c b/drivers/acpi/wmi.c
index cfe2c83..5464cfc 100644
--- a/drivers/acpi/wmi.c
+++ b/drivers/acpi/wmi.c
@@ -217,6 +217,35 @@ static bool find_guid(const char *guid_string, struct wmi_block **out)
return 0;
}

+static acpi_status wmi_method_enable(struct wmi_block *wblock, int enable)
+{
+ struct guid_block *block = NULL;
+ char method[5];
+ struct acpi_object_list input;
+ union acpi_object params[1];
+ acpi_status status;
+ acpi_handle handle;
+
+ block = &wblock->gblock;
+ handle = wblock->handle;
+
+ if (!block)
+ return AE_NOT_EXIST;
+
+ input.count = 1;
+ input.pointer = params;
+ params[0].type = ACPI_TYPE_INTEGER;
+ params[0].integer.value = enable;
+
+ snprintf(method, 5, "WE%02X", block->notify_id);
+ status = acpi_evaluate_object(handle, method, &input, NULL);
+
+ if (status != AE_OK && status != AE_NOT_FOUND)
+ return status;
+ else
+ return AE_OK;
+}
+
/*
* Exported WMI functions
*/
@@ -427,6 +456,7 @@ acpi_status wmi_install_notify_handler(const char *guid,
wmi_notify_handler handler, void *data)
{
struct wmi_block *block;
+ acpi_status status;

if (!guid || !handler)
return AE_BAD_PARAMETER;
@@ -441,7 +471,9 @@ wmi_notify_handler handler, void *data)
block->handler = handler;
block->handler_data = data;

- return AE_OK;
+ status = wmi_method_enable(block, 1);
+
+ return status;
}
EXPORT_SYMBOL_GPL(wmi_install_notify_handler);

@@ -453,6 +485,7 @@ EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
acpi_status wmi_remove_notify_handler(const char *guid)
{
struct wmi_block *block;
+ acpi_status status;

if (!guid)
return AE_BAD_PARAMETER;
@@ -464,10 +497,12 @@ acpi_status wmi_remove_notify_handler(const char *guid)
if (!block->handler)
return AE_NULL_ENTRY;

+ status = wmi_method_enable(block, 0);
+
block->handler = NULL;
block->handler_data = NULL;

- return AE_OK;
+ return status;
}
EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);