Re: [PATCH v4 4/4] watchdog: iTCO_wdg: Make code more clearly with macro definition

[Guenter Roeck]

On 4/26/22 01:17, liuxp11@xxxxxxxxxxxxxxx wrote:
>     On 4/26/22 00:10, Liu Xinpeng wrote:
>      > Using SET_NOIRQ_SYSTEM_SLEEP_PM_OPS reduces redundant code.
>      >
>      > Signed-off-by: Liu Xinpeng <liuxp11@xxxxxxxxxxxxxxx>
>      > Reviewed-by: Tzung-Bi Shih <tzungbi@xxxxxxxxxx>
>      > ---
>      >   drivers/watchdog/iTCO_wdt.c | 12 ++++--------
>      >   1 file changed, 4 insertions(+), 8 deletions(-)
>      >
>      > diff --git a/drivers/watchdog/iTCO_wdt.c b/drivers/watchdog/iTCO_wdt.c
>      > index 3f2f4343644f..8d24cf4f4ca3 100644
>      > --- a/drivers/watchdog/iTCO_wdt.c
>      > +++ b/drivers/watchdog/iTCO_wdt.c
>      > @@ -635,22 +635,18 @@ static int iTCO_wdt_resume_noirq(struct device *dev)
>      >
>      >   return 0;
>      >   }
>      > +#endif /* CONFIG_PM_SLEEP */
>      >
>      >   static const struct dev_pm_ops iTCO_wdt_pm = {
>      > - .suspend_noirq = iTCO_wdt_suspend_noirq,
>      > - .resume_noirq = iTCO_wdt_resume_noirq,
>      > + SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(iTCO_wdt_suspend_noirq,
>      > +       iTCO_wdt_resume_noirq)
>      >   };
>      >
>      > -#define ITCO_WDT_PM_OPS (&iTCO_wdt_pm)
>      > -#else
>      > -#define ITCO_WDT_PM_OPS NULL
>      > -#endif /* CONFIG_PM_SLEEP */
>      > -
>      >   static struct platform_driver iTCO_wdt_driver = {
>      >   .probe          = iTCO_wdt_probe,
>      >   .driver         = {
>      >   .name   = DRV_NAME,
>      > - .pm     = ITCO_WDT_PM_OPS,
>      > + .pm     = &iTCO_wdt_pm,
>      >   },
>      >   };
>      >
>     Sorry, I fail to see how this is an improvement.
>
>     Guenter
>     --->
>     #define NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
>              .suspend_noirq = pm_sleep_ptr(suspend_fn), \
>              .resume_noirq = pm_sleep_ptr(resume_fn), \
>              .freeze_noirq = pm_sleep_ptr(suspend_fn), \
>              .thaw_noirq = pm_sleep_ptr(resume_fn), \
>              .poweroff_noirq = pm_sleep_ptr(suspend_fn), \
>              .restore_noirq = pm_sleep_ptr(resume_fn),
>
>     NOIRQ_SYSTEM_SLEEP_PM_OPS, defined for CONFIG_PM_SLEEP, will
>       point ->suspend_noirq, ->freeze_noirq and ->poweroff_noirq to the same
>       function. Vice versa happens for ->resume_noirq, ->thaw_noirq and ->restore_noirq.
>       (commit 020af89a41c41fd2c92d0da524968dfaba6269f0)
>
>     Some power management occasion needs freeze_noirq/thaw_noirq /poweroff_noirq /restore_noirq.

That isn't what the commit description and subject say. Change description
and subject to describe what is actually done, use __maybe_unused instead
of #ifdef as suggested, and do not invent Reviewed-by: tags.

Also, this is an independent change, and should not be sent together
with the other patches.

Guenter