[PATCH] platform/wmi: Allow wmi module to load when acpi_disabled is set

[Hans de Goede]

Hi,

On 11-Nov-26 14:16, Hans de Goede wrote:
> The core wmi module provides symbols which may be used by other modules.
> These other modules may still function when acpi_disabled is set, but
> the current behavior of acpi_wmi_init() returning -ENODEV when it is set
> causes loading these modules to fail because the wmi module these depend
> on fails to load with -ENODEV.
> 
> One example of this is booting a kernel with both DT and ACPI/WMI support
> on an arm64 systems with devicetree which will lead to acpi_disabled being
> set. Trying to load the amdgpu module will fail in this case because it
> uses symbols from the drivers/acpi/video module which in turn uses symbols
> from the wmi module. Note the video module itself already contains handling
> to still load when acpi_disables is set for similar reasons.
> 
> Fix this by allowing the wmi module to still load and also register
> the class and bus instances since some exported functions like
> wmi_driver_register() rely on these being valid.
> 
> Signed-off-by: Hans de Goede <johannes.goede at oss.qualcomm.com>

Note there is an earlier submitted version of a similar patch here:


> ---
>  drivers/platform/wmi/core.c | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/platform/wmi/core.c b/drivers/platform/wmi/core.c
> index 529825dcfbfe..412f2e23b01d 100644
> --- a/drivers/platform/wmi/core.c
> +++ b/drivers/platform/wmi/core.c
> @@ -1573,9 +1573,6 @@ static int __init acpi_wmi_init(void)
>  {
>  	int error;
>  
> -	if (acpi_disabled)
> -		return -ENODEV;
> -
>  	error = class_register(&wmi_bus_class);
>  	if (error)
>  		return error;
> @@ -1584,6 +1581,9 @@ static int __init acpi_wmi_init(void)
>  	if (error)
>  		goto err_unreg_class;
>  
> +	if (acpi_disabled)
> +		return 0;
> +
>  	error = platform_driver_register(&acpi_wmi_driver);
>  	if (error) {
>  		pr_err("Error loading mapper\n");
> @@ -1603,7 +1603,8 @@ static int __init acpi_wmi_init(void)
>  
>  static void __exit acpi_wmi_exit(void)
>  {
> -	platform_driver_unregister(&acpi_wmi_driver);
> +	if (!acpi_disabled)
> +		platform_driver_unregister(&acpi_wmi_driver);
>  	bus_unregister(&wmi_bus_type);
>  	class_unregister(&wmi_bus_class);
>  }