On Wed, 01 Oct 2014, Randy Dunlap <rdunlap@xxxxxxxxxxxxx> wrote: > On 10/01/14 10:57, Jani Nikula wrote: >> On Wed, 01 Oct 2014, Jim Davis <jim.epost@xxxxxxxxx> wrote: >>> Building with the attached random configuration file, >>> >>> warning: (VIDEO_TIMBERDALE) selects TIMB_DMA which has unmet direct >>> dependencies (DMADEVICES && MFD_TIMBERDALE) >>> warning: (USB_OTG_FSM && FSL_USB2_OTG && USB_MV_OTG) selects USB_OTG >>> which has unmet direct dependencies (USB_SUPPORT && USB && PM_RUNTIME) >>> >>> drivers/built-in.o: In function `intel_panel_setup_backlight': >>> (.text+0x11855d): undefined reference to `backlight_device_register' >>> drivers/built-in.o: In function `intel_panel_destroy_backlight': >>> (.text+0x118624): undefined reference to `backlight_device_unregister' >>> make: *** [vmlinux] Error 1 >> >> It's the combination: >> >>> CONFIG_DRM_I915=y >>> CONFIG_BACKLIGHT_CLASS_DEVICE=m >> >> Not sure what the Kconfig magic spell needs to be when we don't want to >> depend on CONFIG_BACKLIGHT_CLASS_DEVICE but we'll use it if it's enabled >> (y or m). > > Something like: > > depends on BACKLIGHT_CLASS_DEVICE || BACKLIGHT_CLASS_DEVICE=n > > is what we usually use. Oh boy this gets ugly. Trying diff --git a/drivers/gpu/drm/i915/Kconfig b/drivers/gpu/drm/i915/Kconfig index 4e39ab34eb1c..daa453c62aa6 100644 --- a/drivers/gpu/drm/i915/Kconfig +++ b/drivers/gpu/drm/i915/Kconfig @@ -3,6 +3,7 @@ config DRM_I915 depends on DRM depends on X86 && PCI depends on (AGP || AGP=n) + depends on (BACKLIGHT_CLASS_DEVICE || BACKLIGHT_CLASS_DEVICE=n) select INTEL_GTT select AGP_INTEL if AGP select INTERVAL_TREE leads to scripts/kconfig/conf --olddefconfig Kconfig drivers/gpu/drm/i915/Kconfig:1:error: recursive dependency detected! drivers/gpu/drm/i915/Kconfig:1: symbol DRM_I915 depends on BACKLIGHT_CLASS_DEVICE drivers/video/backlight/Kconfig:156: symbol BACKLIGHT_CLASS_DEVICE is selected by DRM_I915 because we depend on ACPI_VIDEO when ACPI is enabled, originally done in commit ecb4aed78dcf09e48c8c34c8c2fa7f5c69344be6 Author: Len Brown <len.brown@xxxxxxxxx> Date: Fri Apr 24 11:33:47 2009 -0400 ACPI, i915: build fix Now, trying to fix that with what seems to me like the obvious dependency, conveying what we really want diff --git a/drivers/gpu/drm/i915/Kconfig b/drivers/gpu/drm/i915/Kconfig index 4e39ab34eb1c..f5a1ee37603e 100644 --- a/drivers/gpu/drm/i915/Kconfig +++ b/drivers/gpu/drm/i915/Kconfig @@ -3,6 +3,7 @@ config DRM_I915 depends on DRM depends on X86 && PCI depends on (AGP || AGP=n) + depends on ((ACPI && ACPI_VIDEO) || ACPI=n) select INTEL_GTT select AGP_INTEL if AGP select INTERVAL_TREE @@ -11,13 +12,6 @@ config DRM_I915 select SHMEM select TMPFS select DRM_KMS_HELPER - # i915 depends on ACPI_VIDEO when ACPI is enabled - # but for select to work, need to select ACPI_VIDEO's dependencies, ick - select BACKLIGHT_LCD_SUPPORT if ACPI - select BACKLIGHT_CLASS_DEVICE if ACPI - select INPUT if ACPI - select ACPI_VIDEO if ACPI - select ACPI_BUTTON if ACPI help Choose this option if you have a system that has "Intel Graphics Media Accelerator" or "HD Graphics" integrated graphics, leads to more fun scripts/kconfig/conf --olddefconfig Kconfig drivers/video/fbdev/Kconfig:5:error: recursive dependency detected! drivers/video/fbdev/Kconfig:5: symbol FB is selected by DRM_KMS_FB_HELPER drivers/gpu/drm/Kconfig:34: symbol DRM_KMS_FB_HELPER is selected by DRM_I915_FBDEV drivers/gpu/drm/i915/Kconfig:40: symbol DRM_I915_FBDEV depends on DRM_I915 drivers/gpu/drm/i915/Kconfig:1: symbol DRM_I915 depends on ACPI_VIDEO drivers/acpi/Kconfig:130: symbol ACPI_VIDEO is selected by BACKLIGHT_CLASS_DEVICE drivers/video/backlight/Kconfig:156: symbol BACKLIGHT_CLASS_DEVICE is selected by FB_BACKLIGHT drivers/video/fbdev/Kconfig:188: symbol FB_BACKLIGHT is selected by PMAC_BACKLIGHT drivers/macintosh/Kconfig:135: symbol PMAC_BACKLIGHT depends on FB and the rabbit hole gets deeper than I thought. I guess it always does. At this point the question is whether "depends on ((ACPI && ACPI_VIDEO) || ACPI=n)" is worth pursuing and makes more sense than the "select foo if ACPI" lines, or do we need to build hacks upon hacks to get this fixed. BR, Jani. -- Jani Nikula, Intel Open Source Technology Center -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html