Re: [PATCH 2/4] mfd: simple-mfd-i2c: Adds Ampere's Altra SMpro support

[Quan Nguyen]

On 26/02/2021 15:31, Lee Jones wrote:
> On Thu, 25 Feb 2021, Quan Nguyen wrote:
>
> > Adds an MFD driver for SMpro found on the Mt.Jade hardware reference
> > platform with Ampere's Altra processor family.
> >
> > Signed-off-by: Quan Nguyen <quan@xxxxxxxxxxxxxxxxxxxxxx>
> > ---
> >   drivers/mfd/Kconfig          | 10 ++++++++++
> >   drivers/mfd/simple-mfd-i2c.c | 15 +++++++++++++--
> >   2 files changed, 23 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> > index b74efa469e90..5414371bdea1 100644
> > --- a/drivers/mfd/Kconfig
> > +++ b/drivers/mfd/Kconfig
> > @@ -77,6 +77,16 @@ config MFD_AS3711
> >   	help
> >   	  Support for the AS3711 PMIC from AMS
> >   
> > +config MFD_SMPRO
> > +	tristate "Ampere Computing MFD SMpro core driver"
> > +	select MFD_SIMPLE_MFD_I2C
>
> Nice to see another user here.
>
> > +	help
> > +	  Say yes here to enable SMpro driver support for Ampere's Altra
> > +	  processor family.
> > +
> > +	  Ampere's Altra SMpro exposes an I2C regmap interface that can
> > +	  be accessed by child devices.
> > +
> >   config MFD_AS3722
> >   	tristate "ams AS3722 Power Management IC"
> >   	select MFD_CORE
> > diff --git a/drivers/mfd/simple-mfd-i2c.c b/drivers/mfd/simple-mfd-i2c.c
> > index 87f684cff9a1..0459a9fbd3f5 100644
> > --- a/drivers/mfd/simple-mfd-i2c.c
> > +++ b/drivers/mfd/simple-mfd-i2c.c
> > @@ -21,14 +21,24 @@ static const struct regmap_config simple_regmap_config = {
> >   	.val_bits = 8,
> >   };
> >   
> > +static const struct regmap_config simple_word_regmap_config = {
> > +	.reg_bits = 8,
> > +	.val_bits = 16,
> > +};
> > +
> >   static int simple_mfd_i2c_probe(struct i2c_client *i2c)
> >   {
> >   	const struct regmap_config *config;
> >   	struct regmap *regmap;
> >   
> >   	config = device_get_match_data(&i2c->dev);
> > -	if (!config)
> > -		config = &simple_regmap_config;
> > +	if (!config) {
> > +		if (of_device_is_compatible(i2c->dev.of_node,
> > +						"ampere,ac01-smpro"))
>
> Could you use 'struct of_device_id's .data attribute instead please?
Thank you, but I'm not sure if I got it right.

Do you mean we could use .data attribute to get the expected 
reg_bits/val_bits values and translate them to simple_word_regmap_config 
without the need to match the compatible string ?

> > +			config = &simple_word_regmap_config;
> > +		else
> > +			config = &simple_regmap_config;
> > +	}
> >   
> >   	regmap = devm_regmap_init_i2c(i2c, config);
> >   	if (IS_ERR(regmap))
> > @@ -39,6 +49,7 @@ static int simple_mfd_i2c_probe(struct i2c_client *i2c)
> >   
> >   static const struct of_device_id simple_mfd_i2c_of_match[] = {
> >   	{ .compatible = "kontron,sl28cpld" },
> > +	{ .compatible = "ampere,ac01-smpro" },
> >   	{}
> >   };
> >   MODULE_DEVICE_TABLE(of, simple_mfd_i2c_of_match);