From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zhang Rui Subject: [PATCH 1/5] Show the physical device node of backlight class device. Date: Mon, 22 Jun 2009 11:31:14 +0800 Message-ID: <1245641478-31805-1-git-send-email-rui.zhang@intel.com> References: Return-path: Received: from mga11.intel.com ([192.55.52.93]:56781 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751636AbZFVDac (ORCPT ); Sun, 21 Jun 2009 23:30:32 -0400 In-Reply-To: Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: lenb@kernel.org Cc: linux-acpi@vger.kernel.org, Zhang Rui Create symbol link from backlight class device to ACPI video device. More and more laptops are shipped with multiple ACPI video devices, while we export only one of them to userspace. With this patch applied, we can know which ACPI video device is used by "cat /sys/class/backlight/acpi_video0/device/path". Signed-off-by: Zhang Rui --- drivers/acpi/video.c | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-) diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c index 1bdfb37..9de143a 100644 --- a/drivers/acpi/video.c +++ b/drivers/acpi/video.c @@ -976,6 +976,11 @@ static void acpi_video_device_find_cap(struct acpi_video_device *device) device->backlight->props.max_brightness = device->brightness->count-3; kfree(name); + result = sysfs_create_link(&device->backlight->dev.kobj, + &device->dev->dev.kobj, "device"); + if (result) + printk(KERN_ERR PREFIX "Create sysfs link\n"); + device->cdev = thermal_cooling_device_register("LCD", device->dev, &video_cooling_ops); if (IS_ERR(device->cdev)) @@ -1990,6 +1995,7 @@ static int acpi_video_bus_put_one_device(struct acpi_video_device *device) status = acpi_remove_notify_handler(device->dev->handle, ACPI_DEVICE_NOTIFY, acpi_video_device_notify); + sysfs_remove_link(&device->backlight->dev.kobj, "device"); backlight_device_unregister(device->backlight); if (device->cdev) { sysfs_remove_link(&device->dev->dev.kobj, -- 1.5.4.4