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

From: Kevin Hilman <khilman@baylibre.com>
To: Nishanth Menon <nm@ti.com>, jerome Neanne <jneanne@baylibre.com>
Cc: Lee Jones <lee@kernel.org>,
	lgirdwood@gmail.com, broonie@kernel.org, robh+dt@kernel.org,
	kristo@kernel.org, dmitry.torokhov@gmail.com,
	krzysztof.kozlowski+dt@linaro.org, catalin.marinas@arm.com,
	will@kernel.org, tony@atomide.com, vigneshr@ti.com,
	bjorn.andersson@linaro.org, shawnguo@kernel.org,
	geert+renesas@glider.be, dmitry.baryshkov@linaro.org,
	marcel.ziswiler@toradex.com, vkoul@kernel.org,
	biju.das.jz@bp.renesas.com, arnd@arndb.de, jeff@labundy.com,
	afd@ti.com, narmstrong@baylibre.com, msp@baylibre.com,
	j-keerthy@ti.com, linux-kernel@vger.kernel.org,
	devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-input@vger.kernel.org, linux-omap@vger.kernel.org
Subject: Re: [PATCH v6 4/6] mfd: tps65219: Add driver for TI TPS65219 PMIC
Date: Mon, 07 Nov 2022 13:14:51 -0800	[thread overview]
Message-ID: <7heduewjp0.fsf@baylibre.com> (raw)
In-Reply-To: <20221105000104.rtj3r6ufqwqmepon@keenly>

Nishanth Menon <nm@ti.com> 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@baylibre.com/
>> 
>> 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.

Kevin