From: Andy Whitcroft When compiling 2.6.19-rc2-mm1 we get the following link failures: drivers/built-in.o(.init.text+0x3076): In function `toshiba_acpi_init': : undefined reference to `backlight_device_register' drivers/built-in.o(.exit.text+0x170): In function `toshiba_acpi_exit': : undefined reference to `backlight_device_unregister' When we build an ACPI module which provides backlight support we need to ensure that the backlight class device is selected. Signed-off-by: Andy Whitcroft Cc: Holger Macht Cc: "Brown, Len" Signed-off-by: Andrew Morton --- drivers/acpi/Kconfig | 2 +- 1 files changed, 1 insertion(+), 1 deletion(-) diff -puN drivers/acpi/Kconfig~add-support-for-the-generic-backlight-device-to-the-toshiba-acpi-driver-fix drivers/acpi/Kconfig --- a/drivers/acpi/Kconfig~add-support-for-the-generic-backlight-device-to-the-toshiba-acpi-driver-fix +++ a/drivers/acpi/Kconfig @@ -234,7 +234,7 @@ config ACPI_IBM_DOCK config ACPI_TOSHIBA tristate "Toshiba Laptop Extras" depends on X86 - select BACKLIGHT_DEVICE + select BACKLIGHT_CLASS_DEVICE ---help--- This driver adds support for access to certain system settings on "legacy free" Toshiba laptops. These laptops can be recognized by _