From mboxrd@z Thu Jan  1 00:00:00 1970
From: wenyou.yang@atmel.com (Yang, Wenyou)
Date: Wed, 20 Jan 2016 15:50:29 +0800
Subject: [PATCH v5 1/2] mfd: act8945a: add Active-semi ACT8945A PMIC MFD
 driver
In-Reply-To: <87d1swvgv8.fsf@dell.be.48ers.dk>
References: <1452747845-2962-1-git-send-email-wenyou.yang@atmel.com>
 <1452747845-2962-2-git-send-email-wenyou.yang@atmel.com>
 <87pox41dy9.fsf@dell.be.48ers.dk>
 <B256D81BAE5131468A838E5D7A243641D63ECA51@penmbx01>
 <8737tzz33h.fsf@dell.be.48ers.dk>
 <B256D81BAE5131468A838E5D7A243641D63F61F4@penmbx01>
 <87d1swvgv8.fsf@dell.be.48ers.dk>
Message-ID: <569F3C45.7090109@atmel.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

Hi Peter,

On 2016/1/20 15:40, Peter Korsgaard wrote:
>>>>>> "Yang," == Yang, Wenyou <Wenyou.Yang@atmel.com> writes:
> Hi,
>
>>> But the charger driver can just as well do:
>   >>
>   >> dev_get_regmap(dev->parent);
>   >>
>   >> instead of:
>   >>
>   >> dev_get_drvdata(pdev->dev.parent)->regmap.
>
>   > For regulator, it works use the core do dev_get_regmap(dev->parent),
>   > but for charger, it need to export *act8945a.
>
> Why?

There is a callback (*get_property)(...), who will read the charger 
register via regmap,

but it doesn't provide the argument for regmap.

include/linux/power_supply.h

struct power_supply_desc {
         [ ... ]
         int (*get_property)(struct power_supply *psy,
                              enum power_supply_property psp,
                              union power_supply_propval *val);
         [ ... ]

}

>
> Just like the regulator core does, your battery driver can do:
>
> dev_get_regmap(dev->parent);
>

Best Regards,
Wenyou Yang