Re: [PATCH v3 07/14] mfd: mt6370: Add Mediatek MT6370 support

From: Andy Shevchenko <andy.shevchenko@gmail.com>
To: ChiaEn Wu <peterwu.pub@gmail.com>
Cc: "open list:FRAMEBUFFER LAYER" <linux-fbdev@vger.kernel.org>,
	"Krogerus, Heikki" <heikki.krogerus@linux.intel.com>,
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	dri-devel <dri-devel@lists.freedesktop.org>,
	Liam Girdwood <lgirdwood@gmail.com>,
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	Chunfeng Yun <chunfeng.yun@mediatek.com>,
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	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
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Subject: Re: [PATCH v3 07/14] mfd: mt6370: Add Mediatek MT6370 support
Date: Thu, 23 Jun 2022 20:00:47 +0200	[thread overview]
Message-ID: <CAHp75Vd95sEQz8y4ZcviUKaC9ic27yitR+VCwkfb38MTTe0mkg@mail.gmail.com> (raw)
In-Reply-To: <20220623115631.22209-8-peterwu.pub@gmail.com>

On Thu, Jun 23, 2022 at 1:59 PM ChiaEn Wu <peterwu.pub@gmail.com> wrote:
>
> From: ChiYuan Huang <cy_huang@richtek.com>
>
> Add Mediatek MT6370 MFD support.

...

> +config MFD_MT6370
> +       tristate "Mediatek MT6370 SubPMIC"
> +       select MFD_CORE
> +       select REGMAP_I2C
> +       select REGMAP_IRQ
> +       depends on I2C
> +       help
> +         Say Y here to enable MT6370 SubPMIC functional support.
> +         It consists of a single cell battery charger with ADC monitoring, RGB
> +         LEDs, dual channel flashlight, WLED backlight driver, display bias
> +         voltage supply, one general purpose LDO, and the USB Type-C & PD
> +         controller complies with the latest USB Type-C and PD standards.

What will be the module name in case it's chosen to be built as a module?

...

>  obj-$(CONFIG_INTEL_SOC_PMIC_BXTWC)  += intel_soc_pmic_bxtwc.o
>  obj-$(CONFIG_INTEL_SOC_PMIC_CHTWC)     += intel_soc_pmic_chtwc.o
>  obj-$(CONFIG_INTEL_SOC_PMIC_CHTDC_TI)  += intel_soc_pmic_chtdc_ti.o
>  obj-$(CONFIG_MFD_MT6360)       += mt6360-core.o
> +obj-$(CONFIG_MFD_MT6370)       += mt6370.o
>  mt6397-objs                    := mt6397-core.o mt6397-irq.o mt6358-irq.o
>  obj-$(CONFIG_MFD_MT6397)       += mt6397.o
>  obj-$(CONFIG_INTEL_SOC_PMIC_MRFLD)     += intel_soc_pmic_mrfld.o

This whole bunch of drivers is in the wrong place in Makefile.

https://lore.kernel.org/all/20220616182524.7956-2-andriy.shevchenko@linux.intel.com/

...

> +#define MT6370_REG_MAXADDR     0x1FF

Wondering if (BIT(10) - 1) gives a better hint on how hardware limits
this (so it will be clear it's 10-bit address).

...

> +static int mt6370_check_vendor_info(struct mt6370_info *info)
> +{
> +       unsigned int devinfo;
> +       int ret;
> +
> +       ret = regmap_read(info->regmap, MT6370_REG_DEV_INFO, &devinfo);
> +       if (ret)
> +               return ret;
> +
> +       switch (FIELD_GET(MT6370_VENID_MASK, devinfo)) {
> +       case MT6370_VENID_RT5081:
> +       case MT6370_VENID_RT5081A:
> +       case MT6370_VENID_MT6370:
> +       case MT6370_VENID_MT6371:
> +       case MT6370_VENID_MT6372P:
> +       case MT6370_VENID_MT6372CP:

return 0;

> +               break;
> +       default:
> +               dev_err(info->dev, "Unknown Vendor ID 0x%02x\n", devinfo);
> +               return -ENODEV;
> +       }
> +
> +       return 0;

...and drop these two lines?

> +}

...

> +       bank_idx = *(u8 *)reg_buf;
> +       bank_addr = *(u8 *)(reg_buf + 1);

Why not

  const u8 *u8_buf = reg_buf;

  bank_idx = u8_buf[0];
  bank_addr = u8_buf[1];

?

...

> +       if (ret < 0)
> +               return ret;
> +       else if (ret != val_size)

Redundant 'else'.

> +               return -EIO;

...

> +       bank_idx = *(u8 *)data;
> +       bank_addr = *(u8 *)(data + 1);

As per above.

-- 
With Best Regards,
Andy Shevchenko