Re: [PATCH 3/9] mfd: mt6397: Split MediaTek MT6366 PMIC out of MT6358

From: AngeloGioacchino Del Regno  <angelogioacchino.delregno@collabora.com>
To: Chen-Yu Tsai <wenst@chromium.org>, Lee Jones <lee@kernel.org>,
	Rob Herring <robh+dt@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Conor Dooley <conor+dt@kernel.org>,
	Matthias Brugger <matthias.bgg@gmail.com>,
	Mark Brown <broonie@kernel.org>
Cc: Zhiyong Tao <zhiyong.tao@mediatek.com>,
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-mediatek@lists.infradead.org
Subject: Re: [PATCH 3/9] mfd: mt6397: Split MediaTek MT6366 PMIC out of MT6358
Date: Thu, 3 Aug 2023 11:01:32 +0200	[thread overview]
Message-ID: <aa8f232f-701a-5b4c-eda8-89fc0e6fe5a8@collabora.com> (raw)
In-Reply-To: <20230803074249.3065586-4-wenst@chromium.org>

Il 03/08/23 09:42, Chen-Yu Tsai ha scritto:
> The MT6366 PMIC is mostly, but not fully, compatible with MT6358. It has
> a different set of regulators. Specifically, it lacks the camera related
> VCAM* LDOs, but has additional VM18, VMDDR, and VSRAM_CORE LDOs.
> 
> Add a separate compatible for the MT6366 PMIC. The regulator cell for
> this new entry uses a new compatible string matching MT6366.
> 
> Fixes: c47383f84909 ("mfd: Add support for the MediaTek MT6366 PMIC")
> Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>

I agree in that the LDOs are a bit different, but that's handled by the
mt6358-regulator driver regardless of the actual devicetree compatible,
as that's selected through a chip_id check.

Finally, looking at the driver implementation itself, the addition of a
specific mt6366 compatible here seems redundant, because the actual HW is
  - Handled by drivers, but
  - Described by bindings

Any other opinions on this?

Regards,
Angelo

> ---
>   drivers/mfd/mt6397-core.c | 31 +++++++++++++++++++++++++++++++
>   1 file changed, 31 insertions(+)
> 
> diff --git a/drivers/mfd/mt6397-core.c b/drivers/mfd/mt6397-core.c
> index f6c1f80f94a4..3f8dfe60a59b 100644
> --- a/drivers/mfd/mt6397-core.c
> +++ b/drivers/mfd/mt6397-core.c
> @@ -206,6 +206,26 @@ static const struct mfd_cell mt6359_devs[] = {
>   	},
>   };
>   
> +static const struct mfd_cell mt6366_devs[] = {
> +	{
> +		.name = "mt6358-regulator",
> +		.of_compatible = "mediatek,mt6366-regulator"
> +	}, {
> +		.name = "mt6358-rtc",
> +		.num_resources = ARRAY_SIZE(mt6358_rtc_resources),
> +		.resources = mt6358_rtc_resources,
> +		.of_compatible = "mediatek,mt6358-rtc",
> +	}, {
> +		.name = "mt6358-sound",
> +		.of_compatible = "mediatek,mt6358-sound"
> +	}, {
> +		.name = "mt6358-keys",
> +		.num_resources = ARRAY_SIZE(mt6358_keys_resources),
> +		.resources = mt6358_keys_resources,
> +		.of_compatible = "mediatek,mt6358-keys"
> +	},
> +};
> +
>   static const struct mfd_cell mt6397_devs[] = {
>   	{
>   		.name = "mt6397-rtc",
> @@ -280,6 +300,14 @@ static const struct chip_data mt6359_core = {
>   	.irq_init = mt6358_irq_init,
>   };
>   
> +static const struct chip_data mt6366_core = {
> +	.cid_addr = MT6358_SWCID,
> +	.cid_shift = 8,
> +	.cells = mt6366_devs,
> +	.cell_size = ARRAY_SIZE(mt6366_devs),
> +	.irq_init = mt6358_irq_init,
> +};
> +
>   static const struct chip_data mt6397_core = {
>   	.cid_addr = MT6397_CID,
>   	.cid_shift = 0,
> @@ -358,6 +386,9 @@ static const struct of_device_id mt6397_of_match[] = {
>   	}, {
>   		.compatible = "mediatek,mt6359",
>   		.data = &mt6359_core,
> +	}, {
> +		.compatible = "mediatek,mt6366",
> +		.data = &mt6366_core,
>   	}, {
>   		.compatible = "mediatek,mt6397",
>   		.data = &mt6397_core,