[PATCH v2] wireless: carl9170: fix LEDS build errors & warnings

[PATCH v2] wireless: carl9170: fix LEDS build errors & warnings

[Randy Dunlap]

kernel test robot reports over 200 build errors and warnings
that are due to this Kconfig problem when CARL9170=m,
MAC80211=y, and LEDS_CLASS=m.

WARNING: unmet direct dependencies detected for MAC80211_LEDS
  Depends on [n]: NET [=y] && WIRELESS [=y] && MAC80211 [=y] && (LEDS_CLASS [=m]=y || LEDS_CLASS [=m]=MAC80211 [=y])
  Selected by [m]:
  - CARL9170_LEDS [=y] && NETDEVICES [=y] && WLAN [=y] && WLAN_VENDOR_ATH [=y] && CARL9170 [=m]

CARL9170_LEDS selects MAC80211_LEDS even though its kconfig
dependencies are not met. This happens because 'select' does not follow
any Kconfig dependency chains.

Fix this by making CARL9170_LEDS always set/enabled if certain
conditions are met: LEDS_CLASS=y or LEDS_CLASS=CARL9170, just as
this is done for Mediatek MT76.

Fixes: 1d7e1e6b1b8ed ("carl9170: Makefile, Kconfig files and MAINTAINERS")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: kernel test robot <lkp@intel.com>
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: Christian Lamparter <chunkeey@googlemail.com>
Cc: linux-wireless@vger.kernel.org
Cc: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Arnd Bergmann <arnd@arndb.de>
---
v2: modify as suggesed by Arnd

 drivers/net/wireless/ath/carl9170/Kconfig |   12 +++---------
 1 file changed, 3 insertions(+), 9 deletions(-)

--- linux-next-20210528.orig/drivers/net/wireless/ath/carl9170/Kconfig
+++ linux-next-20210528/drivers/net/wireless/ath/carl9170/Kconfig
@@ -15,16 +15,10 @@ config CARL9170
 	  If you choose to build a module, it'll be called carl9170.
 
 config CARL9170_LEDS
-	bool "SoftLED Support"
-	depends on CARL9170
-	select MAC80211_LEDS
-	select LEDS_CLASS
-	select NEW_LEDS
+	bool
 	default y
-	help
-	  This option is necessary, if you want your device' LEDs to blink
-
-	  Say Y, unless you need the LEDs for firmware debugging.
+	depends on CARL9170
+	depends on LEDS_CLASS=y || LEDS_CLASS=CARL9170
 
 config CARL9170_DEBUGFS
 	bool "DebugFS Support"

Re: [PATCH v2] wireless: carl9170: fix LEDS build errors & warnings

[Christian Lamparter]

On 29/05/2021 18:44, Randy Dunlap wrote:
> kernel test robot reports over 200 build errors and warnings
> that are due to this Kconfig problem when CARL9170=m,
> MAC80211=y, and LEDS_CLASS=m.
> 
> WARNING: unmet direct dependencies detected for MAC80211_LEDS
>    Depends on [n]: NET [=y] && WIRELESS [=y] && MAC80211 [=y] && (LEDS_CLASS [=m]=y || LEDS_CLASS [=m]=MAC80211 [=y])
>    Selected by [m]:
>    - CARL9170_LEDS [=y] && NETDEVICES [=y] && WLAN [=y] && WLAN_VENDOR_ATH [=y] && CARL9170 [=m]
> 
> CARL9170_LEDS selects MAC80211_LEDS even though its kconfig
> dependencies are not met. This happens because 'select' does not follow
> any Kconfig dependency chains.
> 
> Fix this by making CARL9170_LEDS always set/enabled if certain
> conditions are met: LEDS_CLASS=y or LEDS_CLASS=CARL9170, just as
> this is done for Mediatek MT76.
> 

Hmm, that commit was really a long time ago. In fact it was part of
the initial series for that driver (from September 2010)
1d7e1e6b1b8ed ("carl9170: Makefile, Kconfig files and MAINTAINERS")

 From what I can tell, the "bool / tristate" of LED_CLASS flipped
from tristate (2006) to bool (2010) and back to tristate (2012).

And since MAC80211_LEDS is involved it seems that the latest change
from Arnd:
b64acb28da83 ("ath9k: fix build error with LEDS_CLASS=m")

So, the "select" stuff was present from the start, but it
hasn't been kept up to date I guess.

> Fixes: 1d7e1e6b1b8ed ("carl9170: Makefile, Kconfig files and MAINTAINERS")
> Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
> Reported-by: kernel test robot <lkp@intel.com>
> Cc: Kalle Valo <kvalo@codeaurora.org>
> Cc: Christian Lamparter <chunkeey@googlemail.com>
> Cc: linux-wireless@vger.kernel.org
> Cc: Arnd Bergmann <arnd@arndb.de>
> Suggested-by: Arnd Bergmann <arnd@arndb.de>
> ---
> v2: modify as suggesed by Arnd
> 
>   drivers/net/wireless/ath/carl9170/Kconfig |   12 +++---------
>   1 file changed, 3 insertions(+), 9 deletions(-)
> 
> --- linux-next-20210528.orig/drivers/net/wireless/ath/carl9170/Kconfig
> +++ linux-next-20210528/drivers/net/wireless/ath/carl9170/Kconfig
> @@ -15,16 +15,10 @@ config CARL9170
>   	  If you choose to build a module, it'll be called carl9170.
>   
>   config CARL9170_LEDS
> -	bool "SoftLED Support"
> -	depends on CARL9170
> -	select MAC80211_LEDS
> -	select LEDS_CLASS
> -	select NEW_LEDS
> +	bool
>   	default y
> -	help
> -	  This option is necessary, if you want your device' LEDs to blink
> -
> -	  Say Y, unless you need the LEDs for firmware debugging.
> +	depends on CARL9170
> +	depends on LEDS_CLASS=y || LEDS_CLASS=CARL9170

What happens if CARL9170=M|Y, LED_CLASS=M|Y but MAC80211_LEDS=N?
(with =N, I mean of course: # CONFIG_MAC80211_LEDS is not set. )
 From what I can tell, in this case, the driver will create the LEDs
devices just fine. But since the triggers aren't available (because
they are provided by MAC80211_LEDS) these LEDs will be still called
"tx" and "assoc" but are completely "brainless"/"off".

(carl9170 sets sane default triggers for the LEDS in carl9170_led_register)
---
         err = carl9170_led_register_led(ar, 0, "tx",
                                         ieee80211_get_tx_led_name(ar->hw));
         if (err)
                 goto fail;

         if (ar->features & CARL9170_ONE_LED)
                 return 0;

         err = carl9170_led_register_led(ar, 1, "assoc",
                                         ieee80211_get_assoc_led_name(ar->hw));
---

I would have liked to keep that extra dependency to MAC80211_LEDS.
Would this work with depends/imply? Or will this break in a different way?

Cheers,
Christian

Re: [PATCH v2] wireless: carl9170: fix LEDS build errors & warnings

[Randy Dunlap]

Hi Christian,

On 5/29/21 10:42 AM, Christian Lamparter wrote:
> On 29/05/2021 18:44, Randy Dunlap wrote:
>> kernel test robot reports over 200 build errors and warnings
>> that are due to this Kconfig problem when CARL9170=m,
>> MAC80211=y, and LEDS_CLASS=m.
>>
>> WARNING: unmet direct dependencies detected for MAC80211_LEDS
>>    Depends on [n]: NET [=y] && WIRELESS [=y] && MAC80211 [=y] && (LEDS_CLASS [=m]=y || LEDS_CLASS [=m]=MAC80211 [=y])
>>    Selected by [m]:
>>    - CARL9170_LEDS [=y] && NETDEVICES [=y] && WLAN [=y] && WLAN_VENDOR_ATH [=y] && CARL9170 [=m]
>>
>> CARL9170_LEDS selects MAC80211_LEDS even though its kconfig
>> dependencies are not met. This happens because 'select' does not follow
>> any Kconfig dependency chains.
>>
>> Fix this by making CARL9170_LEDS always set/enabled if certain
>> conditions are met: LEDS_CLASS=y or LEDS_CLASS=CARL9170, just as
>> this is done for Mediatek MT76.
>>
> 
> Hmm, that commit was really a long time ago. In fact it was part of
> the initial series for that driver (from September 2010)
> 1d7e1e6b1b8ed ("carl9170: Makefile, Kconfig files and MAINTAINERS")
> 
> From what I can tell, the "bool / tristate" of LED_CLASS flipped
> from tristate (2006) to bool (2010) and back to tristate (2012).
> 
> And since MAC80211_LEDS is involved it seems that the latest change
> from Arnd:
> b64acb28da83 ("ath9k: fix build error with LEDS_CLASS=m")
> 
> So, the "select" stuff was present from the start, but it
> hasn't been kept up to date I guess.
> 
>> Fixes: 1d7e1e6b1b8ed ("carl9170: Makefile, Kconfig files and MAINTAINERS")
>> Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
>> Reported-by: kernel test robot <lkp@intel.com>
>> Cc: Kalle Valo <kvalo@codeaurora.org>
>> Cc: Christian Lamparter <chunkeey@googlemail.com>
>> Cc: linux-wireless@vger.kernel.org
>> Cc: Arnd Bergmann <arnd@arndb.de>
>> Suggested-by: Arnd Bergmann <arnd@arndb.de>
>> ---
>> v2: modify as suggesed by Arnd
>>
>>   drivers/net/wireless/ath/carl9170/Kconfig |   12 +++---------
>>   1 file changed, 3 insertions(+), 9 deletions(-)
>>
>> --- linux-next-20210528.orig/drivers/net/wireless/ath/carl9170/Kconfig
>> +++ linux-next-20210528/drivers/net/wireless/ath/carl9170/Kconfig
>> @@ -15,16 +15,10 @@ config CARL9170
>>         If you choose to build a module, it'll be called carl9170.
>>     config CARL9170_LEDS
>> -    bool "SoftLED Support"
>> -    depends on CARL9170
>> -    select MAC80211_LEDS
>> -    select LEDS_CLASS
>> -    select NEW_LEDS
>> +    bool
>>       default y
>> -    help
>> -      This option is necessary, if you want your device' LEDs to blink
>> -
>> -      Say Y, unless you need the LEDs for firmware debugging.
>> +    depends on CARL9170
>> +    depends on LEDS_CLASS=y || LEDS_CLASS=CARL9170
> 
> What happens if CARL9170=M|Y, LED_CLASS=M|Y but MAC80211_LEDS=N?
> (with =N, I mean of course: # CONFIG_MAC80211_LEDS is not set. )
> From what I can tell, in this case, the driver will create the LEDs
> devices just fine. But since the triggers aren't available (because
> they are provided by MAC80211_LEDS) these LEDs will be still called
> "tx" and "assoc" but are completely "brainless"/"off".
> 
> (carl9170 sets sane default triggers for the LEDS in carl9170_led_register)
> ---
>        err = carl9170_led_register_led(ar, 0, "tx",
>                                        ieee80211_get_tx_led_name(ar->hw));
>        if (err)
>                goto fail;
> 
>        if (ar->features & CARL9170_ONE_LED)
>                return 0;
> 
>        err = carl9170_led_register_led(ar, 1, "assoc",
>                                        ieee80211_get_assoc_led_name(ar->hw));
> ---
> 
> I would have liked to keep that extra dependency to MAC80211_LEDS.
> Would this work with depends/imply? Or will this break in a different way?

I like that idea.  I've give it a whirl of testing...

thanks.
-- 
~Randy