[PATCH] mux: mmio: Fix missing CONFIG_REGMAP_MMIO

[PATCH] mux: mmio: Fix missing CONFIG_REGMAP_MMIO

[Krzysztof Kozlowski]

MMIO mux uses now regmap_init_mmio(), so one way or another
CONFIG_REGMAP_MMIO should be enabled, because there are no stubs for
!REGMAP_MMIO case:

  ERROR: modpost: "__regmap_init_mmio_clk" [drivers/mux/mux-mmio.ko] undefined!

REGMAP_MMIO should be, because it is a non-visible symbol, but this
causes a circular dependency:

  error: recursive dependency detected!
  symbol IRQ_DOMAIN is selected by REGMAP
  symbol REGMAP default is visible depending on REGMAP_MMIO
  symbol REGMAP_MMIO is selected by MUX_MMIO
  symbol MUX_MMIO depends on MULTIPLEXER
  symbol MULTIPLEXER is selected by MDIO_BUS_MUX_MULTIPLEXER
  symbol MDIO_BUS_MUX_MULTIPLEXER depends on MDIO_DEVICE
  symbol MDIO_DEVICE is selected by PHYLIB
  symbol PHYLIB is selected by ARC_EMAC_CORE
  symbol ARC_EMAC_CORE is selected by EMAC_ROCKCHIP
  symbol EMAC_ROCKCHIP depends on OF_IRQ
  symbol OF_IRQ depends on IRQ_DOMAIN

... which we can break by changing dependency in EMAC_ROCKCHIP from
OF_IRQ to OF.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202505150312.dYbBqUhG-lkp@intel.com/
Fixes: 61de83fd8256 ("mux: mmio: Do not use syscon helper to build regmap")
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

---

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Samuel Holland <samuel@sholland.org>
Cc: Arnd Bergmann <arnd@arndb.de>
---
 drivers/mux/Kconfig              | 1 +
 drivers/net/ethernet/arc/Kconfig | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/mux/Kconfig b/drivers/mux/Kconfig
index 80f015cf6e54..c68132e38138 100644
--- a/drivers/mux/Kconfig
+++ b/drivers/mux/Kconfig
@@ -48,6 +48,7 @@ config MUX_GPIO
 config MUX_MMIO
 	tristate "MMIO/Regmap register bitfield-controlled Multiplexer"
 	depends on OF
+	select REGMAP_MMIO
 	help
 	  MMIO/Regmap register bitfield-controlled Multiplexer controller.
 
diff --git a/drivers/net/ethernet/arc/Kconfig b/drivers/net/ethernet/arc/Kconfig
index 0d400a7d8d91..8ccedece5339 100644
--- a/drivers/net/ethernet/arc/Kconfig
+++ b/drivers/net/ethernet/arc/Kconfig
@@ -26,7 +26,7 @@ config ARC_EMAC_CORE
 config EMAC_ROCKCHIP
 	tristate "Rockchip EMAC support"
 	select ARC_EMAC_CORE
-	depends on OF_IRQ && REGULATOR
+	depends on OF && REGULATOR
 	depends on ARCH_ROCKCHIP || COMPILE_TEST
 	help
 	  Support for Rockchip RK3036/RK3066/RK3188 EMAC ethernet controllers.
-- 
2.45.2

Re: [PATCH] mux: mmio: Fix missing CONFIG_REGMAP_MMIO

[Krzysztof Kozlowski]

On 15/05/2025 16:05, Krzysztof Kozlowski wrote:
> MMIO mux uses now regmap_init_mmio(), so one way or another
> CONFIG_REGMAP_MMIO should be enabled, because there are no stubs for
> !REGMAP_MMIO case:
> 
>   ERROR: modpost: "__regmap_init_mmio_clk" [drivers/mux/mux-mmio.ko] undefined!
> 
> REGMAP_MMIO should be, because it is a non-visible symbol, but this
> causes a circular dependency:
> 
>   error: recursive dependency detected!
>   symbol IRQ_DOMAIN is selected by REGMAP
>   symbol REGMAP default is visible depending on REGMAP_MMIO
>   symbol REGMAP_MMIO is selected by MUX_MMIO
>   symbol MUX_MMIO depends on MULTIPLEXER
>   symbol MULTIPLEXER is selected by MDIO_BUS_MUX_MULTIPLEXER
>   symbol MDIO_BUS_MUX_MULTIPLEXER depends on MDIO_DEVICE
>   symbol MDIO_DEVICE is selected by PHYLIB
>   symbol PHYLIB is selected by ARC_EMAC_CORE
>   symbol ARC_EMAC_CORE is selected by EMAC_ROCKCHIP
>   symbol EMAC_ROCKCHIP depends on OF_IRQ
>   symbol OF_IRQ depends on IRQ_DOMAIN
> 
> ... which we can break by changing dependency in EMAC_ROCKCHIP from
> OF_IRQ to OF.
> 
> Reported-by: kernel test robot <lkp@intel.com>
> Closes: https://lore.kernel.org/oe-kbuild-all/202505150312.dYbBqUhG-lkp@intel.com/
> Fixes: 61de83fd8256 ("mux: mmio: Do not use syscon helper to build regmap")
> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> 
> ---
> 
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Samuel Holland <samuel@sholland.org>
> Cc: Arnd Bergmann <arnd@arndb.de>


Note for netdev folks:

If this looks correct approach, please kindly ack because:
1. The MUX Kconfig part is a fix for a patch in my tree going through
Greg's.
2. Above exposes circular dependency, thus should be fixed in the same
commit.


Best regards,
Krzysztof

Re: [PATCH] mux: mmio: Fix missing CONFIG_REGMAP_MMIO

[Jakub Kicinski]

On Thu, 15 May 2025 16:14:40 +0200 Krzysztof Kozlowski wrote:
> If this looks correct approach, please kindly ack because:
> 1. The MUX Kconfig part is a fix for a patch in my tree going through
> Greg's.
> 2. Above exposes circular dependency, thus should be fixed in the same
> commit.

Acked-by: Jakub Kicinski <kuba@kernel.org>

CC: Hainer who has been trying to improve the MDIO symbols lately
https://lore.kernel.org/all/20250515140555.325601-2-krzysztof.kozlowski@linaro.org/

Re: [PATCH] mux: mmio: Fix missing CONFIG_REGMAP_MMIO

[Arnd Bergmann]

On Thu, May 15, 2025, at 16:05, Krzysztof Kozlowski wrote:
> MMIO mux uses now regmap_init_mmio(), so one way or another
> CONFIG_REGMAP_MMIO should be enabled, because there are no stubs for
> !REGMAP_MMIO case:
>
>   ERROR: modpost: "__regmap_init_mmio_clk" [drivers/mux/mux-mmio.ko] undefined!
>
> REGMAP_MMIO should be, because it is a non-visible symbol, but this
> causes a circular dependency:
>
>   error: recursive dependency detected!
>   symbol IRQ_DOMAIN is selected by REGMAP
>   symbol REGMAP default is visible depending on REGMAP_MMIO
>   symbol REGMAP_MMIO is selected by MUX_MMIO
>   symbol MUX_MMIO depends on MULTIPLEXER
>   symbol MULTIPLEXER is selected by MDIO_BUS_MUX_MULTIPLEXER
>   symbol MDIO_BUS_MUX_MULTIPLEXER depends on MDIO_DEVICE
>   symbol MDIO_DEVICE is selected by PHYLIB
>   symbol PHYLIB is selected by ARC_EMAC_CORE
>   symbol ARC_EMAC_CORE is selected by EMAC_ROCKCHIP
>   symbol EMAC_ROCKCHIP depends on OF_IRQ
>   symbol OF_IRQ depends on IRQ_DOMAIN
>
> ... which we can break by changing dependency in EMAC_ROCKCHIP from
> OF_IRQ to OF.
>
> Reported-by: kernel test robot <lkp@intel.com>
> Closes: 
> https://lore.kernel.org/oe-kbuild-all/202505150312.dYbBqUhG-lkp@intel.com/
> Fixes: 61de83fd8256 ("mux: mmio: Do not use syscon helper to build 
> regmap")
> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
>
> ---
>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Samuel Holland <samuel@sholland.org>
> Cc: Arnd Bergmann <arnd@arndb.de>
> ---

I'm unable to test this on my randconfig setup, but the patch
looks sensible to me.

Acked-by: Arnd Bergmann <arnd@arndb.de>

In the dependency loop above, I think the PHYLIB bit should also
be changed, but that is an independent problem.

I see that OF_IRQ still depends on !SPARC, which may be another
source for problems, so it's possible that anything that tries
to use OF_IRQ causes a build failure on sparc as well.

     Arnd

Re: [PATCH] mux: mmio: Fix missing CONFIG_REGMAP_MMIO

[Krzysztof Kozlowski]

On Thu, 15 May 2025 16:05:56 +0200, Krzysztof Kozlowski wrote:
> MMIO mux uses now regmap_init_mmio(), so one way or another
> CONFIG_REGMAP_MMIO should be enabled, because there are no stubs for
> !REGMAP_MMIO case:
> 
>   ERROR: modpost: "__regmap_init_mmio_clk" [drivers/mux/mux-mmio.ko] undefined!
> 
> REGMAP_MMIO should be, because it is a non-visible symbol, but this
> causes a circular dependency:
> 
> [...]

Applied, thanks!

[1/1] mux: mmio: Fix missing CONFIG_REGMAP_MMIO
      https://git.kernel.org/krzk/linux/c/39bff565b40d26cc51f6e85b3b224c86a563367e

Best regards,
-- 
Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Re: [PATCH] mux: mmio: Fix missing CONFIG_REGMAP_MMIO

[Krzysztof Kozlowski]

On 16/05/2025 10:16, Krzysztof Kozlowski wrote:
> 
> On Thu, 15 May 2025 16:05:56 +0200, Krzysztof Kozlowski wrote:
>> MMIO mux uses now regmap_init_mmio(), so one way or another
>> CONFIG_REGMAP_MMIO should be enabled, because there are no stubs for
>> !REGMAP_MMIO case:
>>
>>   ERROR: modpost: "__regmap_init_mmio_clk" [drivers/mux/mux-mmio.ko] undefined!
>>
>> REGMAP_MMIO should be, because it is a non-visible symbol, but this
>> causes a circular dependency:
>>
>> [...]
> 
> Applied, thanks!
> 
> [1/1] mux: mmio: Fix missing CONFIG_REGMAP_MMIO
>       https://git.kernel.org/krzk/linux/c/39bff565b40d26cc51f6e85b3b224c86a563367e
> 
And dropped. More recursive dependencies are detected, so my fix here is
incomplete.

error: recursive dependency detected!
	symbol REGMAP default is visible depending on REGMAP_MMIO
	symbol REGMAP_MMIO is selected by MUX_MMIO
	symbol MUX_MMIO depends on MULTIPLEXER
	symbol MULTIPLEXER is selected by MDIO_BUS_MUX_MULTIPLEXER
	symbol MDIO_BUS_MUX_MULTIPLEXER depends on MDIO_BUS
	symbol MDIO_BUS is selected by REGMAP

https://krzk.eu/#/builders/43/builds/4855

That's a mess, I need work on this a bit more.

Best regards,
Krzysztof

Re: [PATCH] mux: mmio: Fix missing CONFIG_REGMAP_MMIO

[Krzysztof Kozlowski]

On 16/05/2025 10:26, Krzysztof Kozlowski wrote:
> On 16/05/2025 10:16, Krzysztof Kozlowski wrote:
>>
>> On Thu, 15 May 2025 16:05:56 +0200, Krzysztof Kozlowski wrote:
>>> MMIO mux uses now regmap_init_mmio(), so one way or another
>>> CONFIG_REGMAP_MMIO should be enabled, because there are no stubs for
>>> !REGMAP_MMIO case:
>>>
>>>   ERROR: modpost: "__regmap_init_mmio_clk" [drivers/mux/mux-mmio.ko] undefined!
>>>
>>> REGMAP_MMIO should be, because it is a non-visible symbol, but this
>>> causes a circular dependency:
>>>
>>> [...]
>>
>> Applied, thanks!
>>
>> [1/1] mux: mmio: Fix missing CONFIG_REGMAP_MMIO
>>       https://git.kernel.org/krzk/linux/c/39bff565b40d26cc51f6e85b3b224c86a563367e
>>
> And dropped. More recursive dependencies are detected, so my fix here is
> incomplete.
> 
> error: recursive dependency detected!
> 	symbol REGMAP default is visible depending on REGMAP_MMIO
> 	symbol REGMAP_MMIO is selected by MUX_MMIO
> 	symbol MUX_MMIO depends on MULTIPLEXER
> 	symbol MULTIPLEXER is selected by MDIO_BUS_MUX_MULTIPLEXER
> 	symbol MDIO_BUS_MUX_MULTIPLEXER depends on MDIO_BUS
> 	symbol MDIO_BUS is selected by REGMAP
> 
> https://krzk.eu/#/builders/43/builds/4855
> 
> That's a mess, I need work on this a bit more.


My branch fails with above error because I do not have Heiner's commit
a3e1c0ad8357 ("net: phy: factor out provider part from mdio_bus.c").
Will it reach current RC (rc7) at some point? I could merge the tag to
my next branch to solve it.


Best regards,
Krzysztof

Re: [PATCH] mux: mmio: Fix missing CONFIG_REGMAP_MMIO

[Andrew Davis]

On 5/16/25 3:58 AM, Krzysztof Kozlowski wrote:
> On 16/05/2025 10:26, Krzysztof Kozlowski wrote:
>> On 16/05/2025 10:16, Krzysztof Kozlowski wrote:
>>>
>>> On Thu, 15 May 2025 16:05:56 +0200, Krzysztof Kozlowski wrote:
>>>> MMIO mux uses now regmap_init_mmio(), so one way or another
>>>> CONFIG_REGMAP_MMIO should be enabled, because there are no stubs for
>>>> !REGMAP_MMIO case:
>>>>
>>>>    ERROR: modpost: "__regmap_init_mmio_clk" [drivers/mux/mux-mmio.ko] undefined!
>>>>
>>>> REGMAP_MMIO should be, because it is a non-visible symbol, but this
>>>> causes a circular dependency:
>>>>
>>>> [...]
>>>
>>> Applied, thanks!
>>>
>>> [1/1] mux: mmio: Fix missing CONFIG_REGMAP_MMIO
>>>        https://git.kernel.org/krzk/linux/c/39bff565b40d26cc51f6e85b3b224c86a563367e
>>>
>> And dropped. More recursive dependencies are detected, so my fix here is
>> incomplete.
>>
>> error: recursive dependency detected!
>> 	symbol REGMAP default is visible depending on REGMAP_MMIO
>> 	symbol REGMAP_MMIO is selected by MUX_MMIO
>> 	symbol MUX_MMIO depends on MULTIPLEXER
>> 	symbol MULTIPLEXER is selected by MDIO_BUS_MUX_MULTIPLEXER
>> 	symbol MDIO_BUS_MUX_MULTIPLEXER depends on MDIO_BUS
>> 	symbol MDIO_BUS is selected by REGMAP
>>
>> https://krzk.eu/#/builders/43/builds/4855
>>
>> That's a mess, I need work on this a bit more.
> 
> 
> My branch fails with above error because I do not have Heiner's commit
> a3e1c0ad8357 ("net: phy: factor out provider part from mdio_bus.c").
> Will it reach current RC (rc7) at some point? I could merge the tag to
> my next branch to solve it.
> 
> 

I took a shot at breaking this recursive dependency at the REGMAP config[0].
That should allow REGMAP_MMIO to be selected by MUX_MMIO without touching
stuff here in netdev.

Kconfig is a huge mess at this point, the golden rule of "select should be
used with care" is completely ignored, there are now more uses of select
in Linux Kconfig than the normal "depends on"! Might be time to add that
SAT solver..

Andrew

[0] https://www.spinics.net/lists/kernel/msg5687922.html

Re: [PATCH] mux: mmio: Fix missing CONFIG_REGMAP_MMIO

[Jakub Kicinski]

On Fri, 16 May 2025 10:58:38 +0200 Krzysztof Kozlowski wrote:
> My branch fails with above error because I do not have Heiner's commit
> a3e1c0ad8357 ("net: phy: factor out provider part from mdio_bus.c").
> Will it reach current RC (rc7) at some point? 

No :( We merged it to net-next, so it will have to wait until the merge
window. Worst case you can double apply that change? Maybe git will be
clever enough to auto-resolve. Obviously only if absolutely necessary..
We could also try to sequence our PRs to Linus so that your changes
are rebased after net-next merge. We send our PR in the first day or
two of the MW.