Build failure in linux-next: implicit declaration of acpi_has_method

Build failure in linux-next: implicit declaration of acpi_has_method

[Venkat Rao Bagalkote]

Greetings!!!

IBM CI has reported a build failure on linux-next repo.

Failures:

drivers/bluetooth/btintel_pcie.c: In function 
‘btintel_pcie_acpi_reset_method’:
drivers/bluetooth/btintel_pcie.c:2309:14: error: implicit declaration of 
function ‘acpi_has_method’; did you mean ‘acpi_has_watchdog’? 
[-Werror=implicit-function-declaration]
  2309 |         if (!acpi_has_method(handle, "_PRR")) {
       |              ^~~~~~~~~~~~~~~
       |              acpi_has_watchdog


The function acpi_has_method() lacks a stub definition in 
include/linux/acpi.h
for the !CONFIG_ACPI case, unlike other ACPI utility functions.


Below diff fixes the build failure.


diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index bfacb9475aac..d3804f7f2610 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -1100,6 +1100,11 @@ static inline const char 
*acpi_get_subsystem_id(acpi_handle handle)
         return ERR_PTR(-ENODEV);
  }

+static inline bool acpi_has_method(acpi_handle handle, char *name)
+{
+        return false;
+}
+
  static inline int acpi_register_wakeup_handler(int wake_irq,
         bool (*wakeup)(void *context), void *context)
  {


Please let me know, If this looks good, I can submit a formal patch.


Regards,

Venkat.

Re: Build failure in linux-next: implicit declaration of acpi_has_method

[Rafael J. Wysocki]

On Wed, Apr 15, 2026 at 9:16 AM Venkat Rao Bagalkote
<venkat88@linux.ibm.com> wrote:
>
> Greetings!!!
>
> IBM CI has reported a build failure on linux-next repo.
>
> Failures:
>
> drivers/bluetooth/btintel_pcie.c: In function
> ‘btintel_pcie_acpi_reset_method’:
> drivers/bluetooth/btintel_pcie.c:2309:14: error: implicit declaration of
> function ‘acpi_has_method’; did you mean ‘acpi_has_watchdog’?
> [-Werror=implicit-function-declaration]
>   2309 |         if (!acpi_has_method(handle, "_PRR")) {
>        |              ^~~~~~~~~~~~~~~
>        |              acpi_has_watchdog
>
>
> The function acpi_has_method() lacks a stub definition in
> include/linux/acpi.h
> for the !CONFIG_ACPI case, unlike other ACPI utility functions.

Code that calls acpi_has_method() clearly depends on ACPI though, so
building it in the !CONFIG_ACPI case is questionable.

> Below diff fixes the build failure.
>
>
> diff --git a/include/linux/acpi.h b/include/linux/acpi.h
> index bfacb9475aac..d3804f7f2610 100644
> --- a/include/linux/acpi.h
> +++ b/include/linux/acpi.h
> @@ -1100,6 +1100,11 @@ static inline const char
> *acpi_get_subsystem_id(acpi_handle handle)
>          return ERR_PTR(-ENODEV);
>   }
>
> +static inline bool acpi_has_method(acpi_handle handle, char *name)
> +{
> +        return false;
> +}
> +

This doesn't belong in include/linux/acpi.h.

It might go into include/acpi/acpi_bus.h, but see above.

>   static inline int acpi_register_wakeup_handler(int wake_irq,
>          bool (*wakeup)(void *context), void *context)
>   {

Re: Build failure in linux-next: implicit declaration of acpi_has_method

[Venkat Rao Bagalkote]

On 15/04/26 12:50 pm, Rafael J. Wysocki wrote:
> On Wed, Apr 15, 2026 at 9:16 AM Venkat Rao Bagalkote
> <venkat88@linux.ibm.com> wrote:
>> Greetings!!!
>>
>> IBM CI has reported a build failure on linux-next repo.
>>
>> Failures:
>>
>> drivers/bluetooth/btintel_pcie.c: In function
>> ‘btintel_pcie_acpi_reset_method’:
>> drivers/bluetooth/btintel_pcie.c:2309:14: error: implicit declaration of
>> function ‘acpi_has_method’; did you mean ‘acpi_has_watchdog’?
>> [-Werror=implicit-function-declaration]
>>    2309 |         if (!acpi_has_method(handle, "_PRR")) {
>>         |              ^~~~~~~~~~~~~~~
>>         |              acpi_has_watchdog
>>
>>
>> The function acpi_has_method() lacks a stub definition in
>> include/linux/acpi.h
>> for the !CONFIG_ACPI case, unlike other ACPI utility functions.
> Code that calls acpi_has_method() clearly depends on ACPI though, so
> building it in the !CONFIG_ACPI case is questionable.


Thank you so much for the review and explanation!!

Adding the stub, would just hide the real issue. I guess, proper fix is 
to add the ACPI dependency in Kconfig.



# git diff
diff --git a/drivers/bluetooth/Kconfig b/drivers/bluetooth/Kconfig
index c5d45cf91f88..fc1b37044a9b 100644
--- a/drivers/bluetooth/Kconfig
+++ b/drivers/bluetooth/Kconfig
@@ -502,7 +502,7 @@ config BT_NXPUART

  config BT_INTEL_PCIE
         tristate "Intel HCI PCIe driver"
-       depends on PCI
+       depends on PCI && ACPI
         select BT_INTEL
         select FW_LOADER
         help


Can you please confirm, if this the right approach before I submit a 
formal patch.

Thank you again for your patience and guidance.


Regards,

Venkat.

>> Below diff fixes the build failure.
>>
>>
>> diff --git a/include/linux/acpi.h b/include/linux/acpi.h
>> index bfacb9475aac..d3804f7f2610 100644
>> --- a/include/linux/acpi.h
>> +++ b/include/linux/acpi.h
>> @@ -1100,6 +1100,11 @@ static inline const char
>> *acpi_get_subsystem_id(acpi_handle handle)
>>           return ERR_PTR(-ENODEV);
>>    }
>>
>> +static inline bool acpi_has_method(acpi_handle handle, char *name)
>> +{
>> +        return false;
>> +}
>> +
> This doesn't belong in include/linux/acpi.h.
>
> It might go into include/acpi/acpi_bus.h, but see above.
>
>>    static inline int acpi_register_wakeup_handler(int wake_irq,
>>           bool (*wakeup)(void *context), void *context)
>>    {

Re: Build failure in linux-next: implicit declaration of acpi_has_method

[Rafael J. Wysocki]

On Wed, Apr 15, 2026 at 10:35 AM Venkat Rao Bagalkote
<venkat88@linux.ibm.com> wrote:
>
>
> On 15/04/26 12:50 pm, Rafael J. Wysocki wrote:
> > On Wed, Apr 15, 2026 at 9:16 AM Venkat Rao Bagalkote
> > <venkat88@linux.ibm.com> wrote:
> >> Greetings!!!
> >>
> >> IBM CI has reported a build failure on linux-next repo.
> >>
> >> Failures:
> >>
> >> drivers/bluetooth/btintel_pcie.c: In function
> >> ‘btintel_pcie_acpi_reset_method’:

What kernel is this?

I cannot find the function above in the mainline.

> >> drivers/bluetooth/btintel_pcie.c:2309:14: error: implicit declaration of
> >> function ‘acpi_has_method’; did you mean ‘acpi_has_watchdog’?
> >> [-Werror=implicit-function-declaration]
> >>    2309 |         if (!acpi_has_method(handle, "_PRR")) {
> >>         |              ^~~~~~~~~~~~~~~
> >>         |              acpi_has_watchdog
> >>
> >>
> >> The function acpi_has_method() lacks a stub definition in
> >> include/linux/acpi.h
> >> for the !CONFIG_ACPI case, unlike other ACPI utility functions.
> > Code that calls acpi_has_method() clearly depends on ACPI though, so
> > building it in the !CONFIG_ACPI case is questionable.
>
>
> Thank you so much for the review and explanation!!
>
> Adding the stub, would just hide the real issue. I guess, proper fix is
> to add the ACPI dependency in Kconfig.
>
>
>
> # git diff
> diff --git a/drivers/bluetooth/Kconfig b/drivers/bluetooth/Kconfig
> index c5d45cf91f88..fc1b37044a9b 100644
> --- a/drivers/bluetooth/Kconfig
> +++ b/drivers/bluetooth/Kconfig
> @@ -502,7 +502,7 @@ config BT_NXPUART
>
>   config BT_INTEL_PCIE
>          tristate "Intel HCI PCIe driver"
> -       depends on PCI
> +       depends on PCI && ACPI
>          select BT_INTEL
>          select FW_LOADER
>          help
>
>
> Can you please confirm, if this the right approach before I submit a
> formal patch.

I'm not sure about that.  You need to talk to the driver maintainer.

> Thank you again for your patience and guidance.

You're welcome.

Re: Build failure in linux-next: implicit declaration of acpi_has_method

[Christophe Leroy (CS GROUP)]

Le 15/04/2026 à 16:13, Rafael J. Wysocki a écrit :
> On Wed, Apr 15, 2026 at 10:35 AM Venkat Rao Bagalkote
> <venkat88@linux.ibm.com> wrote:
>>
>>
>> On 15/04/26 12:50 pm, Rafael J. Wysocki wrote:
>>> On Wed, Apr 15, 2026 at 9:16 AM Venkat Rao Bagalkote
>>> <venkat88@linux.ibm.com> wrote:
>>>> Greetings!!!
>>>>
>>>> IBM CI has reported a build failure on linux-next repo.
>>>>
>>>> Failures:
>>>>
>>>> drivers/bluetooth/btintel_pcie.c: In function
>>>> ‘btintel_pcie_acpi_reset_method’:
> 
> What kernel is this?

linux-next, https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next

$ git grep btintel_pcie_acpi_reset_method next-20260415
next-20260415:drivers/bluetooth/btintel_pcie.c:static int 
btintel_pcie_acpi_reset_method(struct btintel_pcie_data *data)
next-20260415:drivers/bluetooth/btintel_pcie.c: ret = 
btintel_pcie_acpi_reset_method(data);

commit 912a499a7955 ("Bluetooth: btintel_pcie: Support Product level reset")

> 
> I cannot find the function above in the mainline.
> 
>>>> drivers/bluetooth/btintel_pcie.c:2309:14: error: implicit declaration of
>>>> function ‘acpi_has_method’; did you mean ‘acpi_has_watchdog’?
>>>> [-Werror=implicit-function-declaration]
>>>>     2309 |         if (!acpi_has_method(handle, "_PRR")) {
>>>>          |              ^~~~~~~~~~~~~~~
>>>>          |              acpi_has_watchdog
>>>>
>>>>
>>>> The function acpi_has_method() lacks a stub definition in
>>>> include/linux/acpi.h
>>>> for the !CONFIG_ACPI case, unlike other ACPI utility functions.
>>> Code that calls acpi_has_method() clearly depends on ACPI though, so
>>> building it in the !CONFIG_ACPI case is questionable.
>>
>>
>> Thank you so much for the review and explanation!!
>>
>> Adding the stub, would just hide the real issue. I guess, proper fix is
>> to add the ACPI dependency in Kconfig.
>>
>>
>>
>> # git diff
>> diff --git a/drivers/bluetooth/Kconfig b/drivers/bluetooth/Kconfig
>> index c5d45cf91f88..fc1b37044a9b 100644
>> --- a/drivers/bluetooth/Kconfig
>> +++ b/drivers/bluetooth/Kconfig
>> @@ -502,7 +502,7 @@ config BT_NXPUART
>>
>>    config BT_INTEL_PCIE
>>           tristate "Intel HCI PCIe driver"
>> -       depends on PCI
>> +       depends on PCI && ACPI
>>           select BT_INTEL
>>           select FW_LOADER
>>           help
>>
>>
>> Can you please confirm, if this the right approach before I submit a
>> formal patch.
> 
> I'm not sure about that.  You need to talk to the driver maintainer.
> 
>> Thank you again for your patience and guidance.
> 
> You're welcome.