diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c index fced27d8e42f..ff79dff371fd 100644 --- a/drivers/acpi/video.c +++ b/drivers/acpi/video.c @@ -150,6 +150,7 @@ struct acpi_video_enumerated_device { struct acpi_video_bus { struct acpi_device *device; + bool backlight_registered; u8 dos_setting; struct acpi_video_enumerated_device *attached_array; u8 attached_count; @@ -1666,88 +1667,89 @@ acpi_video_bus_match(acpi_handle handle, u32 level, void *context, static void acpi_video_dev_register_backlight(struct acpi_video_device *device) { - if (acpi_video_verify_backlight_support()) { - struct backlight_properties props; - struct pci_dev *pdev; - acpi_handle acpi_parent; - struct device *parent = NULL; - int result; - static int count; - char *name; + struct backlight_properties props; + struct pci_dev *pdev; + acpi_handle acpi_parent; + struct device *parent = NULL; + int result; + static int count; + char *name; - result = acpi_video_init_brightness(device); - if (result) - return; - name = kasprintf(GFP_KERNEL, "acpi_video%d", count); - if (!name) - return; - count++; + result = acpi_video_init_brightness(device); + if (result) + return; + name = kasprintf(GFP_KERNEL, "acpi_video%d", count); + if (!name) + return; + count++; - acpi_get_parent(device->dev->handle, &acpi_parent); + acpi_get_parent(device->dev->handle, &acpi_parent); - pdev = acpi_get_pci_dev(acpi_parent); - if (pdev) { - parent = &pdev->dev; - pci_dev_put(pdev); - } - - memset(&props, 0, sizeof(struct backlight_properties)); - props.type = BACKLIGHT_FIRMWARE; - props.max_brightness = device->brightness->count - 3; - device->backlight = backlight_device_register(name, - parent, - device, - &acpi_backlight_ops, - &props); - kfree(name); - if (IS_ERR(device->backlight)) - return; - - /* - * Save current brightness level in case we have to restore it - * before acpi_video_device_lcd_set_level() is called next time. - */ - device->backlight->props.brightness = - acpi_video_get_brightness(device->backlight); - - device->cooling_dev = thermal_cooling_device_register("LCD", - device->dev, &video_cooling_ops); - if (IS_ERR(device->cooling_dev)) { - /* - * Set cooling_dev to NULL so we don't crash trying to - * free it. - * Also, why the hell we are returning early and - * not attempt to register video output if cooling - * device registration failed? - * -- dtor - */ - device->cooling_dev = NULL; - return; - } - - dev_info(&device->dev->dev, "registered as cooling_device%d\n", - device->cooling_dev->id); - result = sysfs_create_link(&device->dev->dev.kobj, - &device->cooling_dev->device.kobj, - "thermal_cooling"); - if (result) - printk(KERN_ERR PREFIX "Create sysfs link\n"); - result = sysfs_create_link(&device->cooling_dev->device.kobj, - &device->dev->dev.kobj, "device"); - if (result) - printk(KERN_ERR PREFIX "Create sysfs link\n"); + pdev = acpi_get_pci_dev(acpi_parent); + if (pdev) { + parent = &pdev->dev; + pci_dev_put(pdev); } + + memset(&props, 0, sizeof(struct backlight_properties)); + props.type = BACKLIGHT_FIRMWARE; + props.max_brightness = device->brightness->count - 3; + device->backlight = backlight_device_register(name, + parent, + device, + &acpi_backlight_ops, + &props); + kfree(name); + if (IS_ERR(device->backlight)) + return; + + /* + * Save current brightness level in case we have to restore it + * before acpi_video_device_lcd_set_level() is called next time. + */ + device->backlight->props.brightness = + acpi_video_get_brightness(device->backlight); + + device->cooling_dev = thermal_cooling_device_register("LCD", + device->dev, &video_cooling_ops); + if (IS_ERR(device->cooling_dev)) { + /* + * Set cooling_dev to NULL so we don't crash trying to free it. + * Also, why the hell we are returning early and not attempt to + * register video output if cooling device registration failed? + * -- dtor + */ + device->cooling_dev = NULL; + return; + } + + dev_info(&device->dev->dev, "registered as cooling_device%d\n", + device->cooling_dev->id); + result = sysfs_create_link(&device->dev->dev.kobj, + &device->cooling_dev->device.kobj, + "thermal_cooling"); + if (result) + printk(KERN_ERR PREFIX "Create sysfs link\n"); + result = sysfs_create_link(&device->cooling_dev->device.kobj, + &device->dev->dev.kobj, "device"); + if (result) + printk(KERN_ERR PREFIX "Create sysfs link\n"); } static int acpi_video_bus_register_backlight(struct acpi_video_bus *video) { struct acpi_video_device *dev; + if (!acpi_video_verify_backlight_support()) + return 0; + mutex_lock(&video->device_list_lock); list_for_each_entry(dev, &video->video_device_list, entry) acpi_video_dev_register_backlight(dev); mutex_unlock(&video->device_list_lock); + video->backlight_registered = true; + video->pm_nb.notifier_call = acpi_video_resume; video->pm_nb.priority = 0; return register_pm_notifier(&video->pm_nb); @@ -1775,13 +1777,20 @@ static void acpi_video_dev_unregister_backlight(struct acpi_video_device *device static int acpi_video_bus_unregister_backlight(struct acpi_video_bus *video) { struct acpi_video_device *dev; - int error = unregister_pm_notifier(&video->pm_nb); + int error; + + if (!video->backlight_registered) + return 0; + + error = unregister_pm_notifier(&video->pm_nb); mutex_lock(&video->device_list_lock); list_for_each_entry(dev, &video->video_device_list, entry) acpi_video_dev_unregister_backlight(dev); mutex_unlock(&video->device_list_lock); + video->backlight_registered = false; + return error; }