eeepc-wmi: never load if legacy device is enabled

If legacy device (SB.ATKD - ASUS010) used by eeepc-laptop
is enabled, don't allow eeepc-wmi to load because:
- eeepc-laptop may be loaded, and can conflict with
  eeepc-wmi (they both try to register eeepc::touchpad
  led for example).
- the WMI interface is inteded to be used when the OS is
  not detected as Win 7. And when this is the case, the
  ASUS010 device is disabled.

Signed-off-by: Corentin Chary <corentincj@iksaif.net>
Signed-off-by: Matthew Garrett <mjg@redhat.com>

1 files changed, 33 insertions, 0 deletions

diff --git a/drivers/platform/x86/eeepc-wmi.c b/drivers/platform/x86/eeepc-wmi.c
index 52274e21ee89..4d38f98aa976 100644
--- a/drivers/platform/x86/eeepc-wmi.c
+++ b/drivers/platform/x86/eeepc-wmi.c
@@ -49,6 +49,8 @@ MODULE_AUTHOR("Yong Wang <yong.y.wang@intel.com>");
 MODULE_DESCRIPTION("Eee PC WMI Hotkey Driver");
 MODULE_LICENSE("GPL");
 
+#define EEEPC_ACPI_HID          "ASUS010" /* old _HID used in eeepc-laptop */
+
 #define EEEPC_WMI_EVENT_GUID    "ABBC0F72-8EA1-11D1-00A0-C90629100000"
 #define EEEPC_WMI_MGMT_GUID     "97845ED0-4E6D-11DE-8A39-0800200C9A66"
 
@@ -861,6 +863,27 @@ static struct platform_driver platform_driver = {
         },
 };
 
+static acpi_status __init eeepc_wmi_parse_device(acpi_handle handle, u32 level,
+                                                 void *context, void **retval)
+{
+        pr_warning("Found legacy ATKD device (%s)", EEEPC_ACPI_HID);
+        *(bool *)context = true;
+        return AE_CTRL_TERMINATE;
+}
+
+static int __init eeepc_wmi_check_atkd(void)
+{
+        acpi_status status;
+        bool found = false;
+
+        status = acpi_get_devices(EEEPC_ACPI_HID, eeepc_wmi_parse_device,
+                                  &found, NULL);
+
+        if (ACPI_FAILURE(status) || !found)
+                return 0;
+        return -1;
+}
+
 static int __init eeepc_wmi_init(void)
 {
         int err;
@@ -871,6 +894,16 @@ static int __init eeepc_wmi_init(void)
                 return -ENODEV;
         }
 
+        if (eeepc_wmi_check_atkd()) {
+                pr_warning("WMI device present, but legacy ATKD device is also "
+                           "present and enabled.");
+                pr_warning("You probably booted with acpi_osi=\"Linux\" or "
+                           "acpi_osi=\"!Windows 2009\"");
+                pr_warning("Can't load eeepc-wmi, use default acpi_osi "
+                           "(preferred) or eeepc-laptop");
+                return -ENODEV;
+        }
+
         platform_device = eeepc_wmi_add();
         if (IS_ERR(platform_device)) {
                 err = PTR_ERR(platform_device);