From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Andrew F. Davis" <afd@ti.com>
Subject: Re: [PATCH 02/13] power: bq24257: Add dead battery reporting
Date: Tue, 1 Sep 2015 14:33:11 -0500
Message-ID: <55E5FD77.10100@ti.com>
References: <1441073435-12349-1-git-send-email-dannenberg@ti.com>
 <1441073435-12349-3-git-send-email-dannenberg@ti.com>
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To: Andreas Dannenberg <dannenberg@ti.com>, Sebastian Reichel <sre@kernel.org>, Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>, David Woodhouse <dwmw2@infradead.org>, Laurentiu Palcu <laurentiu.palcu@intel.com>, Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Cc: linux-pm@vger.kernel.org, devicetree@vger.kernel.org
List-Id: devicetree@vger.kernel.org

On 08/31/2015 09:10 PM, Andreas Dannenberg wrote:
> A missing/disconnected battery is now reported as dead rather than an
> unspecified failure via the charger's sysfs health property.
>
> $ cat health
> Dead

Poor cat :(

>
> Signed-off-by: Andreas Dannenberg <dannenberg@ti.com>
> ---
>   drivers/power/bq24257_charger.c | 4 ++++
>   1 file changed, 4 insertions(+)
>
> diff --git a/drivers/power/bq24257_charger.c b/drivers/power/bq24257_charger.c
> index db81356..0b34528 100644
> --- a/drivers/power/bq24257_charger.c
> +++ b/drivers/power/bq24257_charger.c
> @@ -274,6 +274,10 @@ static int bq24257_power_supply_get_property(struct power_supply *psy,
>   			val->intval = POWER_SUPPLY_HEALTH_SAFETY_TIMER_EXPIRE;
>   			break;
>
> +		case FAULT_NO_BAT:
> +			val->intval = POWER_SUPPLY_HEALTH_DEAD;
> +			break;
> +

I think the best thing to do would be to return -ENODEV as suggested by
power_supply_sysfs.c:305. Also you should probably add the POWER_SUPPLY_PROP_PRESENT
property check and set intval to 0 when there is no battery.

Regards,
Andrew

>   		default:
>   			val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
>   			break;
>