platform/x86: asus-wmi: don't allow eGPU switching if eGPU not connected

Check the ASUS_WMI_DEVID_EGPU_CONNECTED method for eGPU connection
before allowing the ASUS_WMI_DEVID_EGPU method to run.

Signed-off-by: Luke D. Jones <luke@ljones.dev>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230630053552.976579-6-luke@ljones.dev
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c
index 0c8a4a4..821addb 100644 (file)
--- a/drivers/platform/x86/asus-wmi.c
+++ b/drivers/platform/x86/asus-wmi.c
@@ -693,6 +693,15 @@ static ssize_t egpu_enable_store(struct device *dev,
        if (enable > 1)
                return -EINVAL;
 
+       err = asus_wmi_get_devstate_simple(asus, ASUS_WMI_DEVID_EGPU_CONNECTED);
+       if (err < 0)
+               return err;
+       if (err < 1) {
+               err = -ENODEV;
+               pr_warn("Failed to set egpu disable: %d\n", err);
+               return err;
+       }
+
        err = asus_wmi_set_devstate(ASUS_WMI_DEVID_EGPU, enable, &result);
        if (err) {
                pr_warn("Failed to set egpu disable: %d\n", err);