msi-wmi: Make keys and backlight independent

Introduced function msi_wmi_backlight_setup() that initializes backlight
device. Made driver load and work if only one WMI (only for hotkeys or
only for backlight) is present.

Signed-off-by: Maxim Mikityanskiy <maxtram95@gmail.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>

1 files changed, 64 insertions, 37 deletions

diff --git a/drivers/platform/x86/msi-wmi.c b/drivers/platform/x86/msi-wmi.c
index 112ec1488ea8..3a6061985e4d 100644
--- a/drivers/platform/x86/msi-wmi.c
+++ b/drivers/platform/x86/msi-wmi.c
@@ -60,6 +60,8 @@ static struct key_entry msi_wmi_keymap[] = {
 };
 static ktime_t last_pressed[ARRAY_SIZE(msi_wmi_keymap) - 1];
 
+static const char *event_wmi_guid;
+
 static struct backlight_device *backlight;
 
 static int backlight_map[] = { 0x00, 0x33, 0x66, 0x99, 0xCC, 0xFF };
@@ -184,7 +186,7 @@ static void msi_wmi_notify(u32 value, void *context)
 
                         if (key->type == KE_KEY &&
                         /* Brightness is served via acpi video driver */
-                        (!acpi_video_backlight_support() ||
+                        (backlight ||
                         (key->code != MSI_KEY_BRIGHTNESSUP &&
                         key->code != MSI_KEY_BRIGHTNESSDOWN))) {
                                 pr_debug("Send key: 0x%X - "
@@ -202,6 +204,31 @@ msi_wmi_notify_exit:
         kfree(response.pointer);
 }
 
+static int __init msi_wmi_backlight_setup(void)
+{
+        int err;
+        struct backlight_properties props;
+
+        memset(&props, 0, sizeof(struct backlight_properties));
+        props.type = BACKLIGHT_PLATFORM;
+        props.max_brightness = ARRAY_SIZE(backlight_map) - 1;
+        backlight = backlight_device_register(DRV_NAME, NULL, NULL,
+                                              &msi_backlight_ops,
+                                              &props);
+        if (IS_ERR(backlight))
+                return PTR_ERR(backlight);
+
+        err = bl_get(NULL);
+        if (err < 0) {
+                backlight_device_unregister(backlight);
+                return err;
+        }
+
+        backlight->props.brightness = err;
+
+        return 0;
+}
+
 static int __init msi_wmi_input_setup(void)
 {
         int err;
@@ -238,60 +265,60 @@ static int __init msi_wmi_init(void)
 {
         int err;
 
-        if (!wmi_has_guid(MSIWMI_EVENT_GUID)) {
-                pr_err("This machine doesn't have MSI-hotkeys through WMI\n");
-                return -ENODEV;
-        }
-        err = wmi_install_notify_handler(MSIWMI_EVENT_GUID,
-                        msi_wmi_notify, NULL);
-        if (ACPI_FAILURE(err))
-                return -EINVAL;
+        if (wmi_has_guid(MSIWMI_EVENT_GUID)) {
+                err = msi_wmi_input_setup();
+                if (err) {
+                        pr_err("Unable to setup input device\n");
+                        return err;
+                }
 
-        err = msi_wmi_input_setup();
-        if (err)
-                goto err_uninstall_notifier;
-
-        if (!acpi_video_backlight_support()) {
-                struct backlight_properties props;
-                memset(&props, 0, sizeof(struct backlight_properties));
-                props.type = BACKLIGHT_PLATFORM;
-                props.max_brightness = ARRAY_SIZE(backlight_map) - 1;
-                backlight = backlight_device_register(DRV_NAME, NULL, NULL,
-                                                      &msi_backlight_ops,
-                                                      &props);
-                if (IS_ERR(backlight)) {
-                        err = PTR_ERR(backlight);
+                err = wmi_install_notify_handler(MSIWMI_EVENT_GUID,
+                        msi_wmi_notify, NULL);
+                if (ACPI_FAILURE(err)) {
+                        pr_err("Unable to setup WMI notify handler\n");
                         goto err_free_input;
                 }
 
-                err = bl_get(NULL);
-                if (err < 0)
-                        goto err_free_backlight;
+                pr_debug("Event handler installed\n");
+                event_wmi_guid = MSIWMI_EVENT_GUID;
+        }
+
+        if (wmi_has_guid(MSIWMI_BIOS_GUID) && !acpi_video_backlight_support()) {
+                err = msi_wmi_backlight_setup();
+                if (err) {
+                        pr_err("Unable to setup backlight device\n");
+                        goto err_uninstall_handler;
+                }
+                pr_debug("Backlight device created\n");
+        }
 
-                backlight->props.brightness = err;
+        if (!event_wmi_guid && !backlight) {
+                pr_err("This machine doesn't have neither MSI-hotkeys nor backlight through WMI\n");
+                return -ENODEV;
         }
-        pr_debug("Event handler installed\n");
 
         return 0;
 
-err_free_backlight:
-        backlight_device_unregister(backlight);
+err_uninstall_handler:
+        if (event_wmi_guid)
+                wmi_remove_notify_handler(event_wmi_guid);
 err_free_input:
-        sparse_keymap_free(msi_wmi_input_dev);
-        input_unregister_device(msi_wmi_input_dev);
-err_uninstall_notifier:
-        wmi_remove_notify_handler(MSIWMI_EVENT_GUID);
+        if (event_wmi_guid) {
+                sparse_keymap_free(msi_wmi_input_dev);
+                input_unregister_device(msi_wmi_input_dev);
+        }
         return err;
 }
 
 static void __exit msi_wmi_exit(void)
 {
-        if (wmi_has_guid(MSIWMI_EVENT_GUID)) {
-                wmi_remove_notify_handler(MSIWMI_EVENT_GUID);
+        if (event_wmi_guid) {
+                wmi_remove_notify_handler(event_wmi_guid);
                 sparse_keymap_free(msi_wmi_input_dev);
                 input_unregister_device(msi_wmi_input_dev);
-                backlight_device_unregister(backlight);
         }
+        if (backlight)
+                backlight_device_unregister(backlight);
 }
 
 module_init(msi_wmi_init);