3 files changed, 95 insertions, 61 deletions

diff --git a/drivers/acpi/acpi_video.c b/drivers/acpi/acpi_video.c
index 97b711e57bff..c7a6d0b69dab 100644
--- a/drivers/acpi/acpi_video.c
+++ b/drivers/acpi/acpi_video.c
@@ -1984,6 +1984,7 @@ static int instance;
 static int acpi_video_bus_add(struct acpi_device *device)
 {
 	struct acpi_video_bus *video;
+	bool auto_detect;
 	int error;
 	acpi_status status;
 
@@ -2045,10 +2046,20 @@ static int acpi_video_bus_add(struct acpi_device *device)
 	mutex_unlock(&video_list_lock);
 
 	/*
-	 * The userspace visible backlight_device gets registered separately
-	 * from acpi_video_register_backlight().
+	 * If backlight-type auto-detection is used then a native backlight may
+	 * show up later and this may change the result from video to native.
+	 * Therefor normally the userspace visible /sys/class/backlight device
+	 * gets registered separately by the GPU driver calling
+	 * acpi_video_register_backlight() when an internal panel is detected.
+	 * Register the backlight now when not using auto-detection, so that
+	 * when the kernel cmdline or DMI-quirks are used the backlight will
+	 * get registered even if acpi_video_register_backlight() is not called.
 	 */
 	acpi_video_run_bcl_for_osi(video);
+	if (__acpi_video_get_backlight_type(false, &auto_detect) == acpi_backlight_video &&
+	    !auto_detect)
+		acpi_video_bus_register_backlight(video);
+
 	acpi_video_bus_add_notify_handler(video);
 
 	return 0;
diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
index 9531dd0fef50..a96da65057b1 100644
--- a/drivers/acpi/bus.c
+++ b/drivers/acpi/bus.c
@@ -459,85 +459,67 @@ out_free:
                              Notification Handling
    -------------------------------------------------------------------------- */
 
-/*
- * acpi_bus_notify
- * ---------------
- * Callback for all 'system-level' device notifications (values 0x00-0x7F).
+/**
+ * acpi_bus_notify - Global system-level (0x00-0x7F) notifications handler
+ * @handle: Target ACPI object.
+ * @type: Notification type.
+ * @data: Ignored.
+ *
+ * This only handles notifications related to device hotplug.
  */
 static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
 {
 	struct acpi_device *adev;
-	u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
-	bool hotplug_event = false;
 
 	switch (type) {
 	case ACPI_NOTIFY_BUS_CHECK:
 		acpi_handle_debug(handle, "ACPI_NOTIFY_BUS_CHECK event\n");
-		hotplug_event = true;
 		break;
 
 	case ACPI_NOTIFY_DEVICE_CHECK:
 		acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK event\n");
-		hotplug_event = true;
 		break;
 
 	case ACPI_NOTIFY_DEVICE_WAKE:
 		acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_WAKE event\n");
-		break;
+		return;
 
 	case ACPI_NOTIFY_EJECT_REQUEST:
 		acpi_handle_debug(handle, "ACPI_NOTIFY_EJECT_REQUEST event\n");
-		hotplug_event = true;
 		break;
 
 	case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
 		acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK_LIGHT event\n");
 		/* TBD: Exactly what does 'light' mean? */
-		break;
+		return;
 
 	case ACPI_NOTIFY_FREQUENCY_MISMATCH:
 		acpi_handle_err(handle, "Device cannot be configured due "
 				"to a frequency mismatch\n");
-		break;
+		return;
 
 	case ACPI_NOTIFY_BUS_MODE_MISMATCH:
 		acpi_handle_err(handle, "Device cannot be configured due "
 				"to a bus mode mismatch\n");
-		break;
+		return;
 
 	case ACPI_NOTIFY_POWER_FAULT:
 		acpi_handle_err(handle, "Device has suffered a power fault\n");
-		break;
+		return;
 
 	default:
 		acpi_handle_debug(handle, "Unknown event type 0x%x\n", type);
-		break;
+		return;
 	}
 
 	adev = acpi_get_acpi_dev(handle);
-	if (!adev)
-		goto err;
-
-	if (adev->dev.driver) {
-		struct acpi_driver *driver = to_acpi_driver(adev->dev.driver);
-
-		if (driver && driver->ops.notify &&
-		    (driver->flags & ACPI_DRIVER_ALL_NOTIFY_EVENTS))
-			driver->ops.notify(adev, type);
-	}
-
-	if (!hotplug_event) {
-		acpi_put_acpi_dev(adev);
-		return;
-	}
 
-	if (ACPI_SUCCESS(acpi_hotplug_schedule(adev, type)))
+	if (adev && ACPI_SUCCESS(acpi_hotplug_schedule(adev, type)))
 		return;
 
 	acpi_put_acpi_dev(adev);
 
- err:
-	acpi_evaluate_ost(handle, type, ost_code, NULL);
+	acpi_evaluate_ost(handle, type, ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL);
 }
 
 static void acpi_notify_device(acpi_handle handle, u32 event, void *data)
@@ -562,42 +544,51 @@ static u32 acpi_device_fixed_event(void *data)
 	return ACPI_INTERRUPT_HANDLED;
 }
 
-static int acpi_device_install_notify_handler(struct acpi_device *device)
+static int acpi_device_install_notify_handler(struct acpi_device *device,
+					      struct acpi_driver *acpi_drv)
 {
 	acpi_status status;
 
-	if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
+	if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON) {
 		status =
 		    acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 						     acpi_device_fixed_event,
 						     device);
-	else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
+	} else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON) {
 		status =
 		    acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 						     acpi_device_fixed_event,
 						     device);
-	else
-		status = acpi_install_notify_handler(device->handle,
-						     ACPI_DEVICE_NOTIFY,
+	} else {
+		u32 type = acpi_drv->flags & ACPI_DRIVER_ALL_NOTIFY_EVENTS ?
+				ACPI_ALL_NOTIFY : ACPI_DEVICE_NOTIFY;
+
+		status = acpi_install_notify_handler(device->handle, type,
 						     acpi_notify_device,
 						     device);
+	}
 
 	if (ACPI_FAILURE(status))
 		return -EINVAL;
 	return 0;
 }
 
-static void acpi_device_remove_notify_handler(struct acpi_device *device)
+static void acpi_device_remove_notify_handler(struct acpi_device *device,
+					      struct acpi_driver *acpi_drv)
 {
-	if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
+	if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON) {
 		acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 						acpi_device_fixed_event);
-	else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
+	} else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON) {
 		acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 						acpi_device_fixed_event);
-	else
-		acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
+	} else {
+		u32 type = acpi_drv->flags & ACPI_DRIVER_ALL_NOTIFY_EVENTS ?
+				ACPI_ALL_NOTIFY : ACPI_DEVICE_NOTIFY;
+
+		acpi_remove_notify_handler(device->handle, type,
 					   acpi_notify_device);
+	}
 }
 
 /* Handle events targeting \_SB device (at present only graceful shutdown) */
@@ -1039,7 +1030,7 @@ static int acpi_device_probe(struct device *dev)
 		 acpi_drv->name, acpi_dev->pnp.bus_id);
 
 	if (acpi_drv->ops.notify) {
-		ret = acpi_device_install_notify_handler(acpi_dev);
+		ret = acpi_device_install_notify_handler(acpi_dev, acpi_drv);
 		if (ret) {
 			if (acpi_drv->ops.remove)
 				acpi_drv->ops.remove(acpi_dev);
@@ -1062,7 +1053,7 @@ static void acpi_device_remove(struct device *dev)
 	struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
 
 	if (acpi_drv->ops.notify)
-		acpi_device_remove_notify_handler(acpi_dev);
+		acpi_device_remove_notify_handler(acpi_dev, acpi_drv);
 
 	if (acpi_drv->ops.remove)
 		acpi_drv->ops.remove(acpi_dev);
diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c
index fd7cbce8076e..e85729fc481f 100644
--- a/drivers/acpi/video_detect.c
+++ b/drivers/acpi/video_detect.c
@@ -277,6 +277,43 @@ static const struct dmi_system_id video_detect_dmi_table[] = {
 	},
 
 	/*
+	 * Models which need acpi_video backlight control where the GPU drivers
+	 * do not call acpi_video_register_backlight() because no internal panel
+	 * is detected. Typically these are all-in-ones (monitors with builtin
+	 * PC) where the panel connection shows up as regular DP instead of eDP.
+	 */
+	{
+	 .callback = video_detect_force_video,
+	 /* Apple iMac14,1 */
+	 .matches = {
+		DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+		DMI_MATCH(DMI_PRODUCT_NAME, "iMac14,1"),
+		},
+	},
+	{
+	 .callback = video_detect_force_video,
+	 /* Apple iMac14,2 */
+	 .matches = {
+		DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+		DMI_MATCH(DMI_PRODUCT_NAME, "iMac14,2"),
+		},
+	},
+
+	/*
+	 * Older models with nvidia GPU which need acpi_video backlight
+	 * control and where the old nvidia binary driver series does not
+	 * call acpi_video_register_backlight().
+	 */
+	{
+	 .callback = video_detect_force_video,
+	 /* ThinkPad W530 */
+	 .matches = {
+		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad W530"),
+		},
+	},
+
+	/*
 	 * These models have a working acpi_video backlight control, and using
 	 * native backlight causes a regression where backlight does not work
 	 * when userspace is not handling brightness key events. Disable
@@ -782,7 +819,7 @@ static bool prefer_native_over_acpi_video(void)
  * Determine which type of backlight interface to use on this system,
  * First check cmdline, then dmi quirks, then do autodetect.
  */
-static enum acpi_backlight_type __acpi_video_get_backlight_type(bool native)
+enum acpi_backlight_type __acpi_video_get_backlight_type(bool native, bool *auto_detect)
 {
 	static DEFINE_MUTEX(init_mutex);
 	static bool nvidia_wmi_ec_present;
@@ -807,6 +844,9 @@ static enum acpi_backlight_type __acpi_video_get_backlight_type(bool native)
 		native_available = true;
 	mutex_unlock(&init_mutex);
 
+	if (auto_detect)
+		*auto_detect = false;
+
 	/*
 	 * The below heuristics / detection steps are in order of descending
 	 * presedence. The commandline takes presedence over anything else.
@@ -818,6 +858,9 @@ static enum acpi_backlight_type __acpi_video_get_backlight_type(bool native)
 	if (acpi_backlight_dmi != acpi_backlight_undef)
 		return acpi_backlight_dmi;
 
+	if (auto_detect)
+		*auto_detect = true;
+
 	/* Special cases such as nvidia_wmi_ec and apple gmux. */
 	if (nvidia_wmi_ec_present)
 		return acpi_backlight_nvidia_wmi_ec;
@@ -837,15 +880,4 @@ static enum acpi_backlight_type __acpi_video_get_backlight_type(bool native)
 	/* No ACPI video/native (old hw), use vendor specific fw methods. */
 	return acpi_backlight_vendor;
 }
-
-enum acpi_backlight_type acpi_video_get_backlight_type(void)
-{
-	return __acpi_video_get_backlight_type(false);
-}
-EXPORT_SYMBOL(acpi_video_get_backlight_type);
-
-bool acpi_video_backlight_use_native(void)
-{
-	return __acpi_video_get_backlight_type(true) == acpi_backlight_native;
-}
-EXPORT_SYMBOL(acpi_video_backlight_use_native);
+EXPORT_SYMBOL(__acpi_video_get_backlight_type);