Re: [PATCH] backlight: ktd2801: fix LED dependency
From: Daniel Thompson <hidden>
Date: 2024-02-12 12:44:34
Also in:
dri-devel, lkml
Subsystem:
led subsystem, the rest · Maintainers:
Lee Jones, Pavel Machek, Linus Torvalds
On Mon, Feb 12, 2024 at 12:18:12PM +0100, Arnd Bergmann wrote:
quoted hunk ↗ jump to hunk
From: Arnd Bergmann <arnd@arndb.de> The new backlight driver unconditionally selects LEDS_EXPRESSWIRE, which is in a different subsystem that may be disabled here: WARNING: unmet direct dependencies detected for LEDS_EXPRESSWIRE Depends on [n]: NEW_LEDS [=n] && GPIOLIB [=y] Selected by [y]: - BACKLIGHT_KTD2801 [=y] && HAS_IOMEM [=y] && BACKLIGHT_CLASS_DEVICE [=y] Change the select to depends, to ensure the indirect dependency is met as well even when LED support is disabled. Fixes: 66c76c1cd984 ("backlight: Add Kinetic KTD2801 backlight support") Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- drivers/video/backlight/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig index 230bca07b09d..f83f9ef037fc 100644 --- a/drivers/video/backlight/Kconfig +++ b/drivers/video/backlight/Kconfig@@ -185,7 +185,7 @@ config BACKLIGHT_KTD253 config BACKLIGHT_KTD2801 tristate "Backlight Driver for Kinetic KTD2801" - select LEDS_EXPRESSWIRE + depends on LEDS_EXPRESSWIRE
As far as I can tell this resolves the warning by making it impossible to enable BACKLIGHT_KTD2801 unless a largely unrelated driver (LEDS_KTD2692) is also enabled! A better way to resolve this problem might be to eliminate the NEW_LEDS dependency entirely: ~~~
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 64bb2de237e95..a08816cde78ae 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig@@ -186,10 +186,6 @@ config LEDS_EL15203000 To compile this driver as a module, choose M here: the module will be called leds-el15203000. -config LEDS_EXPRESSWIRE - bool - depends on GPIOLIB - config LEDS_TURRIS_OMNIA tristate "LED support for CZ.NIC's Turris Omnia" depends on LEDS_CLASS_MULTICOLOR
@@ -936,3 +932,10 @@ comment "Simple LED drivers" source "drivers/leds/simple/Kconfig" endif # NEW_LEDS + +# This is library code that is useful for LEDs but can be enable/disabled +# independently of NEW_LEDS. In fact it must be independent so it can be +# selected from other sub-systems. +config LEDS_EXPRESSWIRE + bool + depends on GPIOLIB
~~~ Alternatively we could add a "depends on NEW_LEDS" alongside the existing select or just make LEDS_EXPRESSWIRE user selectable. It also looks like we should put back the GPIOLIB dependency to both KTD2801 and KTD2692... and I'll take a mea-culpa for providing bad advice during the review cycles! Daniel.