Re: [PATCH v3 4/6] watchdog: w83627hf_wdt: Store Super I/O configurations in platform data

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] watchdog: w83627hf: macros implicitly depend on local variable base
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commit 7755bf14a50c6dd55f8caec9bfbe7bfcc9d7de23
Author: Paul Louvel <paul.louvel@bootlin.com>

watchdog: w83627hf_wdt: Store Super I/O configurations in platform data

Instead of using global variables, this commit stores Super I/O related
configurations in platform data.

> diff --git a/drivers/watchdog/w83627hf_wdt.c b/drivers/watchdog/w83627hf_wdt.c
> index 44ec2f2e23eab..1ef7b61d7e558 100644
> --- a/drivers/watchdog/w83627hf_wdt.c
> +++ b/drivers/watchdog/w83627hf_wdt.c
[ ... ]
> @@ -76,9 +72,8 @@ MODULE_PARM_DESC(early_disable, "Disable watchdog at boot time (default=0)");
>  #define SIO_REG_CONF_ADDR0	0x2E
>  #define SIO_REG_CONF_ADDR1	0x4E
>  
> -#define WDT_EFER (wdt_io+0)   /* Extended Function Enable Registers */
> -#define WDT_EFIR (wdt_io+0)   /* Extended Function Index Register
> -							(same as EFER) */
> +#define WDT_EFER (base+0)   /* Extended Function Enable Registers */
> +#define WDT_EFIR (base+0)   /* Extended Function Index Register (same as EFER) */
>  #define WDT_EFDR (WDT_EFIR+1) /* Extended Function Data Register */

[Severity: Low]
Does this code implicitly rely on the calling function having a local variable
named base?

This isn't a runtime bug, but the patch replaces a global variable reference
with an undeclared identifier. This creates macros that rely on a magic local
variable name base in the scope of the caller, which can cause build failures
for future developers if they invoke these macros in a function scope that
lacks this local variable. This pattern is noted as an anti-pattern in the
Linux kernel coding style under "Things to avoid when using macros".

Could base be passed explicitly as a parameter to the macro to avoid this
implicit dependency? For example, redefining them as WDT_EFER(base) and
WDT_EFIR(base).

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Sashiko AI review · https://sashiko.dev/#/patchset/20261004-w83627hf_wdt-improvements-v3-0-8e27b518595e@bootlin.com?part=4