Re: [PATCH v3 5/9] mfd: mt6397: Add support for MT6392 pmic

[Lee Jones <lee@kernel.org>]

On Tue, 17 Mar 2026, Luca Leonardo Scorcia wrote:

> From: Fabien Parent <parent.f@gmail.com>
> 
> Update the MT6397 MFD driver to support the MT6392 PMIC.
> 
> Signed-off-by: Fabien Parent <parent.f@gmail.com>
> Signed-off-by: Val Packett <val@packett.cool>
> Signed-off-by: Luca Leonardo Scorcia <l.scorcia@gmail.com>
> ---
>  drivers/mfd/mt6397-core.c            |  46 +++
>  drivers/mfd/mt6397-irq.c             |   8 +
>  include/linux/mfd/mt6392/core.h      |  42 +++
>  include/linux/mfd/mt6392/registers.h | 487 +++++++++++++++++++++++++++
>  include/linux/mfd/mt6397/core.h      |   1 +
>  5 files changed, 584 insertions(+)
>  create mode 100644 include/linux/mfd/mt6392/core.h
>  create mode 100644 include/linux/mfd/mt6392/registers.h
> 
> diff --git a/drivers/mfd/mt6397-core.c b/drivers/mfd/mt6397-core.c
> index 3e58d0764c7e..c4b86a44c68b 100644
> --- a/drivers/mfd/mt6397-core.c
> +++ b/drivers/mfd/mt6397-core.c
> @@ -18,6 +18,7 @@
>  #include <linux/mfd/mt6357/core.h>
>  #include <linux/mfd/mt6358/core.h>
>  #include <linux/mfd/mt6359/core.h>
> +#include <linux/mfd/mt6392/core.h>
>  #include <linux/mfd/mt6397/core.h>
>  #include <linux/mfd/mt6323/registers.h>
>  #include <linux/mfd/mt6328/registers.h>
> @@ -25,6 +26,7 @@
>  #include <linux/mfd/mt6357/registers.h>
>  #include <linux/mfd/mt6358/registers.h>
>  #include <linux/mfd/mt6359/registers.h>
> +#include <linux/mfd/mt6392/registers.h>
>  #include <linux/mfd/mt6397/registers.h>
>  
>  #define MT6323_RTC_BASE		0x8000
> @@ -39,6 +41,9 @@
>  #define MT6358_RTC_BASE		0x0588
>  #define MT6358_RTC_SIZE		0x3c
>  
> +#define MT6392_RTC_BASE		0x8000
> +#define MT6392_RTC_SIZE		0x3e
> +
>  #define MT6397_RTC_BASE		0xe000
>  #define MT6397_RTC_SIZE		0x3e
>  
> @@ -65,6 +70,11 @@ static const struct resource mt6358_rtc_resources[] = {
>  	DEFINE_RES_IRQ(MT6358_IRQ_RTC),
>  };
>  
> +static const struct resource mt6392_rtc_resources[] = {
> +	DEFINE_RES_MEM(MT6392_RTC_BASE, MT6392_RTC_SIZE),
> +	DEFINE_RES_IRQ(MT6392_IRQ_RTC),
> +};
> +
>  static const struct resource mt6397_rtc_resources[] = {
>  	DEFINE_RES_MEM(MT6397_RTC_BASE, MT6397_RTC_SIZE),
>  	DEFINE_RES_IRQ(MT6397_IRQ_RTC),
> @@ -114,6 +124,11 @@ static const struct resource mt6331_keys_resources[] = {
>  	DEFINE_RES_IRQ_NAMED(MT6331_IRQ_STATUS_HOMEKEY, "homekey"),
>  };
>  
> +static const struct resource mt6392_keys_resources[] = {
> +	DEFINE_RES_IRQ_NAMED(MT6392_IRQ_PWRKEY, "powerkey"),
> +	DEFINE_RES_IRQ_NAMED(MT6392_IRQ_FCHRKEY, "homekey"),
> +};
> +
>  static const struct resource mt6397_keys_resources[] = {
>  	DEFINE_RES_IRQ_NAMED(MT6397_IRQ_PWRKEY, "powerkey"),
>  	DEFINE_RES_IRQ_NAMED(MT6397_IRQ_HOMEKEY, "homekey"),
> @@ -253,6 +268,26 @@ static const struct mfd_cell mt6359_devs[] = {
>  	},
>  };
>  
> +static const struct mfd_cell mt6392_devs[] = {
> +	{
> +		.name = "mt6392-rtc",
> +		.num_resources = ARRAY_SIZE(mt6392_rtc_resources),
> +		.resources = mt6392_rtc_resources,
> +		.of_compatible = "mediatek,mt6392-rtc",
> +	}, {
> +		.name = "mt6392-regulator",
> +		.of_compatible = "mediatek,mt6392-regulator",
> +	}, {
> +		.name = "mt6392-pinctrl",
> +		.of_compatible = "mediatek,mt6392-pinctrl",
> +	}, {
> +		.name = "mt6392-keys",
> +		.num_resources = ARRAY_SIZE(mt6392_keys_resources),
> +		.resources = mt6392_keys_resources,
> +		.of_compatible = "mediatek,mt6392-keys"
> +	},
> +};
> +
>  static const struct mfd_cell mt6397_devs[] = {
>  	{
>  		.name = "mt6397-rtc",
> @@ -335,6 +370,14 @@ static const struct chip_data mt6359_core = {
>  	.irq_init = mt6358_irq_init,
>  };
>  
> +static const struct chip_data mt6392_core = {
> +	.cid_addr = MT6392_CID,
> +	.cid_shift = 0,
> +	.cells = mt6392_devs,

I'm not really sure what came over me when I accepted this 6 years ago,
but I have a _strong_ aversion to MFD data being passed through the OF APIs.

Before this patch lands, please could you refactor this driver to only
pass through an identifier through mt6397_of_match[*].data.  Then, you
can match on that via a switch statement where you can allocate each
device's data structures.

This is how the vast majority of MFD drivers work so there should be
lots of examples to work through to make this trivial.

> +	.cell_size = ARRAY_SIZE(mt6392_devs),
> +	.irq_init = mt6397_irq_init,
> +};

-- 
Lee Jones [李琼斯]