building 2.3.36+ I ran in to an 'unmet direct dependensie':
cd /usr/src/linux-2.6
make ARCH=i386 O=/usr/src/psion oldconfig
GEN /usr/src/psion/Makefile
scripts/kconfig/conf --oldconfig Kconfig
warning: (FB_BACKLIGHT && HAS_IOMEM && FB || DRM_I915 && <choice> &&
AGP_INTEL && ACPI || PANEL_SHARP_LS037V7DW01 && HAS_IOMEM && OMAP2_DSS
|| PANEL_ACX565AKM && HAS_IOMEM && OMAP2_DSS && OMAP2_DSS_SDI && SPI ||
USB_APPLEDISPLAY && USB_SUPPORT && USB || ASUS_LAPTOP && X86 &&
X86_PLATFORM_DEVICES && ACPI && !ACPI_ASUS && INPUT && (RFKILL ||
RFKILL=n) || SONY_LAPTOP && X86 && X86_PLATFORM_DEVICES && ACPI && INPUT
&& RFKILL || THINKPAD_ACPI && X86 && X86_PLATFORM_DEVICES && ACPI &&
INPUT && (RFKILL || RFKILL=n) || EEEPC_LAPTOP && X86 &&
X86_PLATFORM_DEVICES && ACPI && INPUT && EXPERIMENTAL && (RFKILL ||
RFKILL=n) && HOTPLUG_PCI || ACPI_ASUS && X86 && X86_PLATFORM_DEVICES &&
ACPI || ACPI_CMPC && X86_PLATFORM_DEVICES && X86 && ACPI && (RFKILL ||
RFKILL=n)) selects BACKLIGHT_CLASS_DEVICE which has unmet direct
dependencies (HAS_IOMEM && BACKLIGHT_LCD_SUPPORT)
warning: (FB_BACKLIGHT && HAS_IOMEM && FB || DRM_I915 && <choice> &&
AGP_INTEL && ACPI || PANEL_SHARP_LS037V7DW01 && HAS_IOMEM && OMAP2_DSS
|| PANEL_ACX565AKM && HAS_IOMEM && OMAP2_DSS && OMAP2_DSS_SDI && SPI ||
USB_APPLEDISPLAY && USB_SUPPORT && USB || ASUS_LAPTOP && X86 &&
X86_PLATFORM_DEVICES && ACPI && !ACPI_ASUS && INPUT && (RFKILL ||
RFKILL=n) || SONY_LAPTOP && X86 && X86_PLATFORM_DEVICES && ACPI && INPUT
&& RFKILL || THINKPAD_ACPI && X86 && X86_PLATFORM_DEVICES && ACPI &&
INPUT && (RFKILL || RFKILL=n) || EEEPC_LAPTOP && X86 &&
X86_PLATFORM_DEVICES && ACPI && INPUT && EXPERIMENTAL && (RFKILL ||
RFKILL=n) && HOTPLUG_PCI || ACPI_ASUS && X86 && X86_PLATFORM_DEVICES &&
ACPI || ACPI_CMPC && X86_PLATFORM_DEVICES && X86 && ACPI && (RFKILL ||
RFKILL=n)) selects BACKLIGHT_CLASS_DEVICE which has unmet direct
dependencies (HAS_IOMEM && BACKLIGHT_LCD_SUPPORT)
#
# configuration written to .config
#
BACKLIGHT_LCD_SUPPORT was set to 'n'. make menuconfig does not force me
to set this setting.
--
Hans