Re: [PATCH v8 2/8] mfd: bd70528: Support ROHM bd70528 PMIC - core

Matti Vaittinen
2019-02-12T09:39:25Z

Thanks Again Lee,

On Tue, Feb 12, 2019 at 09:17:23AM +0000, Lee Jones wrote:
> On Fri, 08 Feb 2019, Matti Vaittinen wrote:
>
> > > I think an exported function with comments would be better.
> > So do you mean you would prefer exported function over the pointer from
> Yes please. Call-back pointers for non-subsystem level actions are a
> bit messy IMHO.

That's fine. I'll go with exported function then =)

> > case it just hides the meaning of values we are passing as arguments.
> > With raw assignment we at least have some idea what the 0x40 or 0x20 are
> > referring to =)
>
> Well I do agree with your last comment.
>
> Maybe doing the following would help with the ugliness (i.e. the shear
> number of chars):
>
> unsigned int type_reg_offset_inc = 0;
> for (i = BD70528_INT_GPIO0; i <= BD70528_INT_GPIO3; i++) {
> <blar> *t = irqs[i].type;
> t->type_reg_offset = type_reg_offset_inc;
> t->type_rising_val = 0x20;
> t->type_falling_val = 0x10;
> t->type_level_high_val = 0x40;
> t->type_level_low_val = 0x50;
> t->types_supported =
> (IRQ_TYPE_EDGE_BOTH | IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW);
> type_reg_offset_inc += 2;
> }

I'll go with this for next version.

> > > > > > + /* wdt_set must be called rtc_timer_lock held */
> > > > >
> > > > > This doesn't make sense.
> > > >
> > > > Umm.. The comment does not make sense? Maybe I can explain it further.
> > >
> > > "wdt_set must be called when the rtc_timer_lock is held"
> >
> > Yes. I wanted to say that who-ever is calling the wdt_set function
> > below, should have locked the rtc_timer_lock mutex (last in this
> > struct). The function does not do locking inside because we want the RTC
> > to be able to perform:
> >
> > lock
> > disable wdt (store original state)
> > set RTC
> > return wdt original state
> > unlock
> >
> > Locking is needed so that we can exclude the watchdog enabling or
> > disabling the WDT timer between moments when RTC is getting the original
> > WDT state and re-turning back the old state. Without the lock we have a
> > risk that WDT-driver enables or disables the timer when RTC is being
> > set, and RTC overwrites the watchdog driver changes when writing back
> > the old state. I hope this makes sense now... Any suggestions how to
> > explain this nicely in english?
>
> I think I did already:
>
> "wdt_set must be called when the rtc_timer_lock is held"
>
> Actually, this is a little ambiguous. A better sentence could read:
>
> "rtc_timer_lock must be taken before calling wdt_set()"

Sure. I'll ruthlessy plagiarize that sentence. (And as I am not at all
sure if "ruthlessy plagiarize" actually means what I think it does -
I tried to say that I'll take your suggestion and use it :] )

Once again, thanks for the help =)

Br,
Matti