The DRM_SIL_SII8620 kconfig has a weak `imply` dependency
on EXTCON, which causes issues when sii8620 is built
as a builtin and EXTCON is built as a module.
The symptoms are 'undefined reference' errors caused
by the symbols in EXTCON not being available
to the sii8620 driver.
Signed-off-by: Robert Foss <[email protected]>
Reported-by: kernel test robot <[email protected]>
---
Changes since v1:
- Fix typo on comment
drivers/gpu/drm/bridge/Kconfig | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
index 22a467abd3e9..2289b44613af 100644
--- a/drivers/gpu/drm/bridge/Kconfig
+++ b/drivers/gpu/drm/bridge/Kconfig
@@ -169,7 +169,7 @@ config DRM_SIL_SII8620
tristate "Silicon Image SII8620 HDMI/MHL bridge"
depends on OF
select DRM_KMS_HELPER
- imply EXTCON
+ depends on EXTCON || !EXTCON # if EXTCON=m, this cannot be built-in
depends on RC_CORE || !RC_CORE
help
Silicon Image SII8620 HDMI/MHL bridge chip driver.
--
2.31.0.30.g398dba342d.dirty
On 4/8/21 6:07 AM, Robert Foss wrote:
> The DRM_SIL_SII8620 kconfig has a weak `imply` dependency
> on EXTCON, which causes issues when sii8620 is built
> as a builtin and EXTCON is built as a module.
>
> The symptoms are 'undefined reference' errors caused
> by the symbols in EXTCON not being available
> to the sii8620 driver.
>
> Signed-off-by: Robert Foss <[email protected]>
> Reported-by: kernel test robot <[email protected]>
> ---
>
> Changes since v1:
> - Fix typo on comment
>
> drivers/gpu/drm/bridge/Kconfig | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
> index 22a467abd3e9..2289b44613af 100644
> --- a/drivers/gpu/drm/bridge/Kconfig
> +++ b/drivers/gpu/drm/bridge/Kconfig
> @@ -169,7 +169,7 @@ config DRM_SIL_SII8620
> tristate "Silicon Image SII8620 HDMI/MHL bridge"
> depends on OF
> select DRM_KMS_HELPER
> - imply EXTCON
> + depends on EXTCON || !EXTCON # if EXTCON=m, this cannot be built-in
> depends on RC_CORE || !RC_CORE
> help
> Silicon Image SII8620 HDMI/MHL bridge chip driver.
>
That gives me: (on linux-next 20210409)
drivers/gpu/drm/Kconfig:77:error: recursive dependency detected!
drivers/gpu/drm/Kconfig:77: symbol DRM_KMS_HELPER is selected by DRM_SIL_SII8620
drivers/gpu/drm/bridge/Kconfig:168: symbol DRM_SIL_SII8620 depends on EXTCON
drivers/extcon/Kconfig:2: symbol EXTCON is selected by CHARGER_MANAGER
drivers/power/supply/Kconfig:499: symbol CHARGER_MANAGER depends on POWER_SUPPLY
drivers/power/supply/Kconfig:2: symbol POWER_SUPPLY is selected by OLPC_XO1_SCI
arch/x86/Kconfig:2757: symbol OLPC_XO1_SCI depends on GPIO_CS5535
drivers/gpio/Kconfig:1156: symbol GPIO_CS5535 depends on GPIOLIB
drivers/gpio/Kconfig:14: symbol GPIOLIB is selected by I2C_MUX_LTC4306
drivers/i2c/muxes/Kconfig:47: symbol I2C_MUX_LTC4306 depends on I2C
drivers/i2c/Kconfig:8: symbol I2C is selected by FB_DDC
drivers/video/fbdev/Kconfig:63: symbol FB_DDC depends on FB
drivers/video/fbdev/Kconfig:12: symbol FB is selected by DRM_KMS_FB_HELPER
drivers/gpu/drm/Kconfig:83: symbol DRM_KMS_FB_HELPER depends on DRM_KMS_HELPER
For a resolution refer to Documentation/kbuild/kconfig-language.rst
subsection "Kconfig recursive dependency limitations"
--
~Randy
Hey Randy,
Thanks for looking at this!
On Fri, 9 Apr 2021 at 18:38, Randy Dunlap <[email protected]> wrote:
>
> On 4/8/21 6:07 AM, Robert Foss wrote:
> > The DRM_SIL_SII8620 kconfig has a weak `imply` dependency
> > on EXTCON, which causes issues when sii8620 is built
> > as a builtin and EXTCON is built as a module.
> >
> > The symptoms are 'undefined reference' errors caused
> > by the symbols in EXTCON not being available
> > to the sii8620 driver.
> >
> > Signed-off-by: Robert Foss <[email protected]>
> > Reported-by: kernel test robot <[email protected]>
> > ---
> >
> > Changes since v1:
> > - Fix typo on comment
> >
> > drivers/gpu/drm/bridge/Kconfig | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
> > index 22a467abd3e9..2289b44613af 100644
> > --- a/drivers/gpu/drm/bridge/Kconfig
> > +++ b/drivers/gpu/drm/bridge/Kconfig
> > @@ -169,7 +169,7 @@ config DRM_SIL_SII8620
> > tristate "Silicon Image SII8620 HDMI/MHL bridge"
> > depends on OF
> > select DRM_KMS_HELPER
> > - imply EXTCON
> > + depends on EXTCON || !EXTCON # if EXTCON=m, this cannot be built-in
> > depends on RC_CORE || !RC_CORE
> > help
> > Silicon Image SII8620 HDMI/MHL bridge chip driver.
> >
>
> That gives me: (on linux-next 20210409)
>
> drivers/gpu/drm/Kconfig:77:error: recursive dependency detected!
> drivers/gpu/drm/Kconfig:77: symbol DRM_KMS_HELPER is selected by DRM_SIL_SII8620
> drivers/gpu/drm/bridge/Kconfig:168: symbol DRM_SIL_SII8620 depends on EXTCON
> drivers/extcon/Kconfig:2: symbol EXTCON is selected by CHARGER_MANAGER
> drivers/power/supply/Kconfig:499: symbol CHARGER_MANAGER depends on POWER_SUPPLY
> drivers/power/supply/Kconfig:2: symbol POWER_SUPPLY is selected by OLPC_XO1_SCI
> arch/x86/Kconfig:2757: symbol OLPC_XO1_SCI depends on GPIO_CS5535
> drivers/gpio/Kconfig:1156: symbol GPIO_CS5535 depends on GPIOLIB
> drivers/gpio/Kconfig:14: symbol GPIOLIB is selected by I2C_MUX_LTC4306
> drivers/i2c/muxes/Kconfig:47: symbol I2C_MUX_LTC4306 depends on I2C
> drivers/i2c/Kconfig:8: symbol I2C is selected by FB_DDC
> drivers/video/fbdev/Kconfig:63: symbol FB_DDC depends on FB
> drivers/video/fbdev/Kconfig:12: symbol FB is selected by DRM_KMS_FB_HELPER
> drivers/gpu/drm/Kconfig:83: symbol DRM_KMS_FB_HELPER depends on DRM_KMS_HELPER
> For a resolution refer to Documentation/kbuild/kconfig-language.rst
> subsection "Kconfig recursive dependency limitations"
I'm not sure how to avoid this circular dependency. The above solution
is what I've seen w/r to issues like [1]. Clearly it doesn't work in
this situation. `select EXTCON` doesn't seem to cause this dependency
error, but I'm not sure it accurately represents the dependency
sii8620 has on extcon.
[1] https://lore.kernel.org/lkml/[email protected]/