msi-laptop: Disable brightness control for new EC

It seems that existing brightness control works only for old EC models.
On newer ones auto_brightness access always timeouts and lcd_level
always shows 0. So disable brightness control for new EC models. It
works fine with ACPI video driver anyway.

Signed-off-by: Maxim Mikityanskiy <maxtram95@gmail.com>
Signed-off-by: Lee, Chun-Yi <jlee@suse.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>

1 files changed, 27 insertions, 12 deletions

diff --git a/drivers/platform/x86/msi-laptop.c b/drivers/platform/x86/msi-laptop.c
index 28bcbb21d120..6b2293875672 100644
--- a/drivers/platform/x86/msi-laptop.c
+++ b/drivers/platform/x86/msi-laptop.c
@@ -546,8 +546,6 @@ static DEVICE_ATTR(turbo_cooldown, 0444, show_turbo_cooldown, NULL);
 static DEVICE_ATTR(auto_fan, 0644, show_auto_fan, store_auto_fan);
 
 static struct attribute *msipf_attributes[] = {
-        &dev_attr_lcd_level.attr,
-        &dev_attr_auto_brightness.attr,
         &dev_attr_bluetooth.attr,
         &dev_attr_wlan.attr,
         &dev_attr_touchpad.attr,
@@ -558,10 +556,20 @@ static struct attribute *msipf_attributes[] = {
         NULL
 };
 
+static struct attribute *msipf_old_attributes[] = {
+        &dev_attr_lcd_level.attr,
+        &dev_attr_auto_brightness.attr,
+        NULL
+};
+
 static struct attribute_group msipf_attribute_group = {
         .attrs = msipf_attributes
 };
 
+static struct attribute_group msipf_old_attribute_group = {
+        .attrs = msipf_old_attributes
+};
+
 static struct platform_driver msipf_driver = {
         .driver = {
                 .name = "msi-laptop-pf",
@@ -1062,7 +1070,7 @@ static int __init msi_init(void)
 
         /* Register backlight stuff */
 
-        if (acpi_video_backlight_support()) {
+        if (!quirks->old_ec_model || acpi_video_backlight_support()) {
                 pr_info("Brightness ignored, must be controlled by ACPI video driver\n");
         } else {
                 struct backlight_properties props;
@@ -1108,14 +1116,19 @@ static int __init msi_init(void)
                                                 &dev_attr_threeg);
                 if (ret)
                         goto fail_platform_device2;
-        }
+        } else {
+                ret = sysfs_create_group(&msipf_device->dev.kobj,
+                                         &msipf_old_attribute_group);
+                if (ret)
+                        goto fail_platform_device2;
 
-        /* Disable automatic brightness control by default because
-         * this module was probably loaded to do brightness control in
-         * software. */
+                /* Disable automatic brightness control by default because
+                 * this module was probably loaded to do brightness control in
+                 * software. */
 
-        if (auto_brightness != 2)
-                set_auto_brightness(auto_brightness);
+                if (auto_brightness != 2)
+                        set_auto_brightness(auto_brightness);
+        }
 
         pr_info("driver " MSI_DRIVER_VERSION " successfully loaded\n");
 
@@ -1163,9 +1176,11 @@ static void __exit msi_cleanup(void)
         platform_driver_unregister(&msipf_driver);
         backlight_device_unregister(msibl_device);
 
-        /* Enable automatic brightness control again */
-        if (auto_brightness != 2)
-                set_auto_brightness(1);
+        if (quirks->old_ec_model) {
+                /* Enable automatic brightness control again */
+                if (auto_brightness != 2)
+                        set_auto_brightness(1);
+        }
 
         pr_info("driver unloaded\n");
 }