Re: [PATCH] platform/x86: dell-wmi-sysman: correct an initialization failure

[mark gross <mgross@linux.intel.com>]

On Thu, Feb 18, 2021 at 01:17:23PM -0600, Mario Limonciello wrote:
> On Dell systems that don't support this interface the module is
> mistakingly returning error code "0", when it should be returning
> -ENODEV.  Correct a logic error to guarantee the correct return code.
> 
> Cc: Divya Bharathi <Divya_Bharathi@Dell.com>
> Reported-by: Alexander Naumann <alexandernaumann@gmx.de>
> Signed-off-by: Mario Limonciello <mario.limonciello@dell.com>
> ---
>  drivers/platform/x86/dell-wmi-sysman/biosattr-interface.c     | 4 +++-
>  drivers/platform/x86/dell-wmi-sysman/passwordattr-interface.c | 4 +++-
>  drivers/platform/x86/dell-wmi-sysman/sysman.c                 | 4 ++--
>  3 files changed, 8 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/platform/x86/dell-wmi-sysman/biosattr-interface.c b/drivers/platform/x86/dell-wmi-sysman/biosattr-interface.c
> index f95d8ddace5a..8d59f81f9db4 100644
> --- a/drivers/platform/x86/dell-wmi-sysman/biosattr-interface.c
> +++ b/drivers/platform/x86/dell-wmi-sysman/biosattr-interface.c
> @@ -175,7 +175,9 @@ static struct wmi_driver bios_attr_set_interface_driver = {
>  
>  int init_bios_attr_set_interface(void)
>  {
> -	return wmi_driver_register(&bios_attr_set_interface_driver);
> +	int ret = wmi_driver_register(&bios_attr_set_interface_driver);
I have to ask if the propper fix should be in wmi_driver_register
> +
> +	return wmi_priv.bios_attr_wdev ? ret : -ENODEV;
Also, is there any point to call wmi_driver_register if returning -ENODEV?
i.e. should the call to driver register be wrapped in a test for
bios_atter_wdev?


>  }
>  
>  void exit_bios_attr_set_interface(void)
> diff --git a/drivers/platform/x86/dell-wmi-sysman/passwordattr-interface.c b/drivers/platform/x86/dell-wmi-sysman/passwordattr-interface.c
> index 5780b4d94759..bf449dc5ff47 100644
> --- a/drivers/platform/x86/dell-wmi-sysman/passwordattr-interface.c
> +++ b/drivers/platform/x86/dell-wmi-sysman/passwordattr-interface.c
> @@ -142,7 +142,9 @@ static struct wmi_driver bios_attr_pass_interface_driver = {
>  
>  int init_bios_attr_pass_interface(void)
>  {
> -	return wmi_driver_register(&bios_attr_pass_interface_driver);
> +	int ret = wmi_driver_register(&bios_attr_pass_interface_driver);
> +
> +	return wmi_priv.password_attr_wdev ? ret : -ENODEV;
same comments as above only for password_atter_wdev.

--mark

>  }
>  
>  void exit_bios_attr_pass_interface(void)
> diff --git a/drivers/platform/x86/dell-wmi-sysman/sysman.c b/drivers/platform/x86/dell-wmi-sysman/sysman.c
> index cb81010ba1a2..d9ad0e83b66f 100644
> --- a/drivers/platform/x86/dell-wmi-sysman/sysman.c
> +++ b/drivers/platform/x86/dell-wmi-sysman/sysman.c
> @@ -513,13 +513,13 @@ static int __init sysman_init(void)
>  	}
>  
>  	ret = init_bios_attr_set_interface();
> -	if (ret || !wmi_priv.bios_attr_wdev) {
> +	if (ret) {
>  		pr_debug("failed to initialize set interface\n");
>  		goto fail_set_interface;
>  	}
>  
>  	ret = init_bios_attr_pass_interface();
> -	if (ret || !wmi_priv.password_attr_wdev) {
> +	if (ret) {
>  		pr_debug("failed to initialize pass interface\n");
>  		goto fail_pass_interface;
>  	}
> -- 
> 2.25.1
>