Re: [PATCH] pinctrl: lpc18xx: Use define directive for PIN_CONFIG_GPIO_PIN_INT

[Vladimir Zapolskiy]

Hi Nathan,

thank you for your patch.

On 11/01/2018 02:52 AM, Nathan Chancellor wrote:
> Clang warns when one enumerated type is implicitly converted to another:
> 
> drivers/pinctrl/pinctrl-lpc18xx.c:643:29: warning: implicit conversion
> from enumeration type 'enum lpc18xx_pin_config_param' to different
> enumeration type 'enum pin_config_param' [-Wenum-conversion]
>         {"nxp,gpio-pin-interrupt", PIN_CONFIG_GPIO_PIN_INT, 0},
>         ~                          ^~~~~~~~~~~~~~~~~~~~~~~
> drivers/pinctrl/pinctrl-lpc18xx.c:648:12: warning: implicit conversion
> from enumeration type 'enum lpc18xx_pin_config_param' to different
> enumeration type 'enum pin_config_param' [-Wenum-conversion]
>         PCONFDUMP(PIN_CONFIG_GPIO_PIN_INT, "gpio pin int", NULL, true),
>         ~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> ./include/linux/pinctrl/pinconf-generic.h:163:11: note: expanded from
> macro 'PCONFDUMP'
>         .param = a, .display = b, .format = c, .has_arg = d     \
>                  ^
> 2 warnings generated.
> 
> It is expected that pinctrl drivers can extend pin_config_param because
> of the gap between PIN_CONFIG_END and PIN_CONFIG_MAX so this conversion
> isn't an issue. Most drivers that take advantage of this define the
> PIN_CONFIG variables as constants, rather than enumerated values. Do the
> same thing here so that Clang no longer warns.
> 
> Link: https://github.com/ClangBuiltLinux/linux/issues/140
> Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
> ---
>  drivers/pinctrl/pinctrl-lpc18xx.c | 5 +----
>  1 file changed, 1 insertion(+), 4 deletions(-)
> 
> diff --git a/drivers/pinctrl/pinctrl-lpc18xx.c b/drivers/pinctrl/pinctrl-lpc18xx.c
> index a14bc5e5fc24..4bee606088e1 100644
> --- a/drivers/pinctrl/pinctrl-lpc18xx.c
> +++ b/drivers/pinctrl/pinctrl-lpc18xx.c
> @@ -631,13 +631,10 @@ static const struct pinctrl_pin_desc lpc18xx_pins[] = {
>  };
>  
>  /**
> - * enum lpc18xx_pin_config_param - possible pin configuration parameters
>   * @PIN_CONFIG_GPIO_PIN_INT: route gpio to the gpio pin interrupt
>   * 	controller.
>   */
> -enum lpc18xx_pin_config_param {
> -	PIN_CONFIG_GPIO_PIN_INT = PIN_CONFIG_END + 1,
> -};
> +#define PIN_CONFIG_GPIO_PIN_INT		(PIN_CONFIG_END + 1)
>  
>  static const struct pinconf_generic_params lpc18xx_params[] = {
>  	{"nxp,gpio-pin-interrupt", PIN_CONFIG_GPIO_PIN_INT, 0},
> 

The change, if it is applied, starts to produce a W=1 warning:

	drivers/pinctrl/pinctrl-lpc18xx.c:634: warning: Cannot understand  * @PIN_CONFIG_GPIO_PIN_INT: route gpio to the gpio pin interrupt on line 634 - I thought it was a doc line

Could you please take a look how to satisfy process_name() check from scripts/kernel-doc?

My proposals are:
1) change the first line of the comment block from '/**' to '/*',
2) remove '@' prefix symbol and place pinconf description on one line.

--
Best wishes,
Vladimir