Re: [PATCH v6 4/6] mfd: tps65219: Add driver for TI TPS65219 PMIC

[Andrew Davis]

On 11/10/22 11:00 AM, Kevin Hilman wrote:
> jerome Neanne <jneanne@xxxxxxxxxxxx> writes:
>
> > On 09/11/2022 22:59, Andrew Davis wrote:
> > > On 11/7/22 3:14 PM, Kevin Hilman wrote:
> > > > Nishanth Menon <nm@xxxxxx> writes:
> > > >
> > > > > On 13:58-20221104, jerome Neanne wrote:
> > > > > >
> > > > > [...]
> > > > >
> > > > > > > Can you try an compile with W=1 please.
> > > > > > This raise one warning on mfd:
> > > > > > drivers/mfd/tps65219.c:28:12: warning: ‘tps65219_soft_shutdown’
> > > > > > defined but
> > > > > > not used [-Wunused-function]
> > > > > >      28 | static int tps65219_soft_shutdown(struct tps65219 *tps)
> > > > > >         |            ^~~~~~~~~~~~~~~~~~~~~~
> > > > > > soft_shutdown has been validated and is used in TI baseline even if not
> > > > > > hooked in upstream version further to this review:
> > > > > > https://lore.kernel.org/lkml/20220825150224.826258-5-msp@xxxxxxxxxxxx/
> > > > > >
> > > > > > It was a TI requirement to implement it...
> > > > > > Let me know if you want me to remove this function or if we can keep
> > > > > > it like
> > > > > > this.
> > > > >
> > > > > There are platforms without psci, correct? I think the comment was to
> > > > > drop the force override with system-power-controller property,
> > > > >
> > > > > if (!pm_power_off) {
> > > > >      tps65219_i2c_client = client;
> > > > >      pm_power_off = &tps65219_pm_power_off;
> > > > > }
> > > > >
> > > > > Could still be valid for such platforms, no? I do see that the
> > > > > capability that the PMIC has - which is software shutdown is a valid
> > > > > feature that we support in many different PMIC drivers. Is'nt the job of
> > > > > the driver to introduce the functionality in a manner that is
> > > > > appropriate to the OS framework?
> > > >
> > > > Yeah, I think Nishanth is right here.
> > > >
> > > > We should probably keep the `if (!pm_power_off)` part so the PMIC will
> > > > be used if PSCI is not, but it also allows an easy way to test/use the
> > > > PMIC
> > > > shutdown functionality downstream if needed.
> > >
> > > Then should be using the sys-off handler API[0] so it doesn't block PSCI
> > > which is also switching over[1].
> > >
> > > Andrew
> > >
> > > [0] https://lwn.net/Articles/894511/
> > > [1] https://www.spinics.net/lists/arm-kernel/msg1024127.html
> > Can we go for upstream with v7 without tps65219_soft_shutdown. Then if
> > everyone agrees with Andrew proposal, I'll submit a separate patch which
> > adds implementation of tps65219_soft_shutdown support through sys-off
> > handler.
> >
> > So that we are not blocking upstream in case further
> > discussions/alignment are required.
>
> Seems OK to me.  Nishanth?  Andrew?
>
> But I think you'll need to at least submit a v8 without the unused
> code/dead code that Lee pointed out.

If you need the v8 anyway, then add support through sys-off in
that spin, should only be a couple lines of change.

Andrew