Re: [PATCH v6 6/9] mfd: axp20x: Add support for RSB based AXP223 PMIC

[Lee Jones]

On Mon, 11 Jan 2016, Chen-Yu Tsai wrote:
> On Mon, Jan 11, 2016 at 5:24 PM, Lee Jones <lee.jones@xxxxxxxxxx> wrote:
> > On Thu, 17 Dec 2015, Chen-Yu Tsai wrote:
> >
> >> The AXP223 is a new PMIC commonly paired with Allwinner A23/A33 SoCs.
> >> It is functionally identical to AXP221; only the regulator default
> >> voltage/status and the external host interface are different.
> >>
> >> Signed-off-by: Chen-Yu Tsai <wens@xxxxxxxx>
> >> ---
> >>  drivers/mfd/Kconfig        | 11 +++++++
> >>  drivers/mfd/Makefile       |  1 +
> >>  drivers/mfd/axp20x-rsb.c   | 78 ++++++++++++++++++++++++++++++++++++++++++++++
> >>  drivers/mfd/axp20x.c       |  2 ++
> >>  include/linux/mfd/axp20x.h |  1 +
> >>  5 files changed, 93 insertions(+)
> >>  create mode 100644 drivers/mfd/axp20x-rsb.c

[...]

> >> +static int axp20x_rsb_probe(struct sunxi_rsb_device *rdev)
> >> +{
> >> +     struct axp20x_dev *axp20x;
> >> +     int ret;
> >> +
> >> +     axp20x = devm_kzalloc(&rdev->dev, sizeof(*axp20x), GFP_KERNEL);
> >> +     if (!axp20x)
> >> +             return -ENOMEM;
> >> +
> >> +     axp20x->dev = &rdev->dev;
> >> +     axp20x->irq = rdev->irq;
> >> +     sunxi_rsb_device_set_drvdata(rdev, axp20x);
> >
> > What's the point of this call?  Why do you need a sunxi_ variant?
> 
> This is an inline call defined in include/linux/sunxi-rsb.h,
> which is equivalent to dev_set_drvdata(&rdev->dev, data).
> 
> It seems many subsystems or bus drivers have this pattern.
> 
>     git grep void.*_set_drvdata include/linux/ | wc -l
> 
> yields 34, not including dev_set_drvdata itself and this sunxi_rsb
> variant.

That doesn't answer my question.  Why is it required?

Looks like superfluous churn to me.  Aggregation for the sake of it.

> >> +     ret = axp20x_match_device(axp20x);
> >> +     if (ret)
> >> +             return ret;
> >> +
> >> +     axp20x->regmap = devm_regmap_init_sunxi_rsb(rdev, axp20x->regmap_cfg);
> >> +     if (IS_ERR(axp20x->regmap)) {
> >> +             ret = PTR_ERR(axp20x->regmap);
> >> +             dev_err(&rdev->dev, "regmap init failed: %d\n", ret);
> >> +             return ret;
> >> +     }
> >> +
> >> +     return axp20x_device_probe(axp20x);
> >> +}
> >> +
> >> +static int axp20x_rsb_remove(struct sunxi_rsb_device *rdev)
> >> +{
> >> +     struct axp20x_dev *axp20x = sunxi_rsb_device_get_drvdata(rdev);
> >> +
> >> +     return axp20x_device_remove(axp20x);
> >> +}
> >> +
> >> +static const struct of_device_id axp20x_rsb_of_match[] = {
> >> +     { .compatible = "x-powers,axp223", .data = (void *)AXP223_ID },
> >> +     { },
> >> +};
> >> +MODULE_DEVICE_TABLE(of, axp20x_rsb_of_match);
> >> +
> >> +static struct sunxi_rsb_driver axp20x_rsb_driver = {
> >> +     .driver = {
> >> +             .name   = "axp20x-rsb",
> >> +             .of_match_table = of_match_ptr(axp20x_rsb_of_match),
> >> +     },
> >> +     .probe  = axp20x_rsb_probe,
> >> +     .remove = axp20x_rsb_remove,
> >> +};
> >> +module_sunxi_rsb_driver(axp20x_rsb_driver);
> >> +
> >> +MODULE_DESCRIPTION("PMIC MFD sunXi RSB driver for AXP20X");
> >> +MODULE_AUTHOR("Chen-Yu Tsai <wens@xxxxxxxx>");
> >> +MODULE_LICENSE("GPL v2");
> >> diff --git a/drivers/mfd/axp20x.c b/drivers/mfd/axp20x.c
> >> index 54a00168da26..968d77fb95d8 100644
> >> --- a/drivers/mfd/axp20x.c
> >> +++ b/drivers/mfd/axp20x.c
> >> @@ -33,6 +33,7 @@ static const char * const axp20x_model_names[] = {
> >>       "AXP202",
> >>       "AXP209",
> >>       "AXP221",
> >> +     "AXP223",
> >>       "AXP288",
> >>  };
> >>
> >> @@ -616,6 +617,7 @@ int axp20x_match_device(struct axp20x_dev *axp20x)
> >>               axp20x->regmap_irq_chip = &axp20x_regmap_irq_chip;
> >>               break;
> >>       case AXP221_ID:
> >> +     case AXP223_ID:
> >>               axp20x->nr_cells = ARRAY_SIZE(axp22x_cells);
> >>               axp20x->cells = axp22x_cells;
> >>               axp20x->regmap_cfg = &axp22x_regmap_config;
> >> diff --git a/include/linux/mfd/axp20x.h b/include/linux/mfd/axp20x.h
> >> index 00697c6ad8b0..d82e7d51372b 100644
> >> --- a/include/linux/mfd/axp20x.h
> >> +++ b/include/linux/mfd/axp20x.h
> >> @@ -18,6 +18,7 @@ enum {
> >>       AXP202_ID,
> >>       AXP209_ID,
> >>       AXP221_ID,
> >> +     AXP223_ID,
> >>       AXP288_ID,
> >>       NR_AXP20X_VARIANTS,
> >>  };
> >

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org â Open source software for ARM SoCs
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