msi-wmi: depend on backlight and fix corner-cases problems

Now depends on BACKLIGHT_CLASS_DEVICE.
Driver will return an error if it can't get actual backlight value
Fix remapping of brightness keys when backlight is not controlled by ACPI.

Signed-off-by: Anisse Astier <anisse@astier.eu>
Signed-off-by: Len Brown <len.brown@intel.com>

2 files changed, 16 insertions, 8 deletions

diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index 1f82d6df96e1..a006dec3b3ef 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -369,6 +369,7 @@ config MSI_WMI
         tristate "MSI WMI extras"
         depends on ACPI_WMI
         depends on INPUT
+        depends on BACKLIGHT_CLASS_DEVICE
         select INPUT_SPARSEKMAP
         help
          Say Y here if you want to support WMI-based hotkeys on MSI laptops.
diff --git a/drivers/platform/x86/msi-wmi.c b/drivers/platform/x86/msi-wmi.c
index e25b80c530f7..0c8fe145c4af 100644
--- a/drivers/platform/x86/msi-wmi.c
+++ b/drivers/platform/x86/msi-wmi.c
@@ -53,11 +53,15 @@ MODULE_ALIAS("dmi:*:svnMICRO-STARINTERNATIONAL*:pnMS-6638:*");
 #define dprintk(msg...) pr_debug(DRV_PFX msg)
 
 #define KEYCODE_BASE 0xD0
+#define MSI_WMI_BRIGHTNESSUP   KEYCODE_BASE
+#define MSI_WMI_BRIGHTNESSDOWN (KEYCODE_BASE + 1)
+#define MSI_WMI_VOLUMEUP       (KEYCODE_BASE + 2)
+#define MSI_WMI_VOLUMEDOWN     (KEYCODE_BASE + 3)
 static struct key_entry msi_wmi_keymap[] = {
-        { KE_KEY, KEYCODE_BASE,     {KEY_BRIGHTNESSUP} },
-        { KE_KEY, KEYCODE_BASE + 1, {KEY_BRIGHTNESSDOWN} },
-        { KE_KEY, KEYCODE_BASE + 2, {KEY_VOLUMEUP} },
-        { KE_KEY, KEYCODE_BASE + 3, {KEY_VOLUMEDOWN} },
+        { KE_KEY, MSI_WMI_BRIGHTNESSUP,   {KEY_BRIGHTNESSUP} },
+        { KE_KEY, MSI_WMI_BRIGHTNESSDOWN, {KEY_BRIGHTNESSDOWN} },
+        { KE_KEY, MSI_WMI_VOLUMEUP,       {KEY_VOLUMEUP} },
+        { KE_KEY, MSI_WMI_VOLUMEDOWN,     {KEY_VOLUMEDOWN} },
         { KE_END, 0}
 };
 static ktime_t last_pressed[ARRAY_SIZE(msi_wmi_keymap) - 1];
@@ -110,12 +114,14 @@ static int msi_wmi_set_block(int instance, int value)
 
 static int bl_get(struct backlight_device *bd)
 {
-        int level, err, ret = 0;
+        int level, err, ret;
 
         /* Instance 1 is "get backlight", cmp with DSDT */
         err = msi_wmi_query_block(1, &ret);
-        if (err)
+        if (err) {
                 printk(KERN_ERR DRV_PFX "Could not query backlight: %d\n", err);
+                return -EINVAL;
+        }
         dprintk("Get: Query block returned: %d\n", ret);
         for (level = 0; level < ARRAY_SIZE(backlight_map); level++) {
                 if (backlight_map[level] == ret) {
@@ -180,8 +186,9 @@ static void msi_wmi_notify(u32 value, void *context)
 
                         if (key->type == KE_KEY &&
                         /* Brightness is served via acpi video driver */
-                        (backlight || (key->keycode != KEY_BRIGHTNESSUP &&
-                        key->keycode != KEY_BRIGHTNESSDOWN))) {
+                        (!acpi_video_backlight_support() ||
+                        (key->code != MSI_WMI_BRIGHTNESSUP &&
+                        key->code != MSI_WMI_BRIGHTNESSDOWN))) {
                                 dprintk("Send key: 0x%X - "
                                         "Input layer keycode: %d\n", key->code,
                                          key->keycode);