Re: [RESEND PATCH 3/5] charger: max14577: Configure battery-dependent settings from DTS

[Mark Rutland <mark.rutland@arm.com>]

On Tue, Jul 01, 2014 at 08:01:58AM +0100, Krzysztof Kozlowski wrote:
> Remove hard-coded values for:
>  - Fast Charge current,
>  - End Of Charge current,
>  - Fast Charge timer,
>  - Overvoltage Protection Threshold,
>  - Battery Constant Voltage,
> and use DTS to configure them. This allows using the max14577 charger
> driver with different batteries.
> 
> Now the charger driver requires valid configuration data from DTS. In
> case of wrong configuration data it fails during probe. Patch adds
> of_compatible to the charger mfd cell in MFD driver core.
> 
> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
> Cc: Kyungmin Park <kyungmin.park@samsung.com>
> Cc: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
> Cc: David Woodhouse <dwmw2@infradead.org>
> Cc: Jenny Tc <jenny.tc@intel.com>
> Acked-by: Lee Jones <lee.jones@linaro.org>
> ---
>  drivers/mfd/max14577.c               |   5 +-
>  drivers/power/max14577_charger.c     | 232 +++++++++++++++++++++++++++++++----
>  include/linux/mfd/max14577-private.h |  16 +++
>  include/linux/mfd/max14577.h         |   8 ++
>  4 files changed, 233 insertions(+), 28 deletions(-)

[...]

> +       pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
> +       if (!pdata) {
> +               dev_err(&pdev->dev, "Memory alloc for charger pdata failed\n");
> +               return ERR_PTR(-ENOMEM);
> +       }
> +
> +       ret = of_property_read_u32(np, "maxim,fast-charge-timer",
> +                       &pdata->fast_charge_timer);
> +       if (ret)
> +               return ERR_PTR(ret);
> +
> +       ret = of_property_read_u32(np, "maxim,constant-uvolt",
> +                       &pdata->constant_uvolt);
> +       if (ret)
> +               return ERR_PTR(ret);
> +
> +       ret = of_property_read_u32(np, "maxim,fast-charge-uamp",
> +                       &pdata->fast_charge_uamp);
> +       if (ret)
> +               return ERR_PTR(ret);
> +
> +       ret = of_property_read_u32(np, "maxim,eoc-uamp", &pdata->eoc_uamp);
> +       if (ret)
> +               return ERR_PTR(ret);
> +
> +       ret = of_property_read_u32(np, "maxim,ovp-uvolt", &pdata->ovp_uvolt);
> +       if (ret)
> +               return ERR_PTR(ret);

None of the fields being read into are u32 per the structure definition
below. Please use a u32 temporary variable or make the fields u32
values.

It would also be a good idea to print a warning as to _which_ field is
missing and/or invalid as that really helps someone writing a DTS to
figure out why the device isn't probing.

[...]

> +struct max14577_charger_platform_data {
> +       unsigned int fast_charge_timer;
> +       unsigned int constant_uvolt;
> +       unsigned int fast_charge_uamp;
> +       unsigned int eoc_uamp;
> +       unsigned int ovp_uvolt;
> +};

Thanks,
Mark.