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

Mark Rutland
2014-07-03T11:36:53Z

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.