If a driver registers with WMI, and none of the GUIDs in its ID table
is present on the system, then that driver will not be probed and
automatically loaded. However, it is still possible to load such a
driver explicitly on a system which doesn't include the relevant
hardware.
Update wmi_driver_register to test for the presence of at least one
GUID from the driver's ID table at driver registration time, and
fail registration if none are found.
Signed-off-by: Daniel Dadap <ddadap@xxxxxxxxxx>
---
drivers/platform/x86/wmi.c | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c
index 941739db7199..19aa23d1cf8e 100644
--- a/drivers/platform/x86/wmi.c
+++ b/drivers/platform/x86/wmi.c
@@ -130,6 +130,21 @@ static bool find_guid(const char *guid_string, struct wmi_block **out)
return false;
}
+static bool find_driver_guid(const struct wmi_driver *wdriver)
+{
+ const struct wmi_device_id *id;
+
+ if (wdriver == NULL)
+ return false;
+
+ for (id = wdriver->id_table; *id->guid_string; id++) {
+ if (find_guid(id->guid_string, NULL))
+ return true;
+ }
+
+ return false;
+}
+
static const void *find_guid_context(struct wmi_block *wblock,
struct wmi_driver *wdriver)
{
@@ -1419,6 +1434,9 @@ static int acpi_wmi_probe(struct platform_device *device)
int __must_check __wmi_driver_register(struct wmi_driver *driver,
struct module *owner)
{
+ if (!find_driver_guid(driver))
+ return -ENODEV;
+
driver->driver.owner = owner;
driver->driver.bus = &wmi_bus_type;
--
2.18.4
