From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1422885AbcIZQc7 (ORCPT ); Mon, 26 Sep 2016 12:32:59 -0400 Received: from mail-lf0-f68.google.com ([209.85.215.68]:33911 "EHLO mail-lf0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S938895AbcIZQc5 (ORCPT ); Mon, 26 Sep 2016 12:32:57 -0400 Date: Mon, 26 Sep 2016 18:32:52 +0200 From: Krzysztof Kozlowski To: Wolfgang Wiedmeyer Cc: Krzysztof Kozlowski , sre@kernel.org, dbaryshkov@gmail.com, dwmw2@infradead.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] power: supply: max17042_battery: add technology property support Message-ID: <20160926163252.GA3196@kozik-lap> References: <20160926105510.GA8140@kozik-lap> <87eg46x1ir.fsf@machinist.wiedmeyer.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <87eg46x1ir.fsf@machinist.wiedmeyer.de> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Sep 26, 2016 at 02:56:44PM +0200, Wolfgang Wiedmeyer wrote: > > Krzysztof Kozlowski writes: > > > On Sun, Sep 25, 2016 at 11:10:11PM +0200, Wolfgang Wiedmeyer wrote: > >> This patch reports the battery technology as Li-ion. > >> > >> Signed-off-by: Wolfgang Wiedmeyer > >> --- > >> drivers/power/max17042_battery.c | 4 ++++ > >> 1 file changed, 4 insertions(+) > >> > >> diff --git a/drivers/power/max17042_battery.c b/drivers/power/max17042_battery.c > >> index 20cb1fd..43cb5df 100644 > >> --- a/drivers/power/max17042_battery.c > >> +++ b/drivers/power/max17042_battery.c > >> @@ -92,6 +92,7 @@ static enum power_supply_property max17042_battery_props[] = { > >> POWER_SUPPLY_PROP_TEMP_MIN, > >> POWER_SUPPLY_PROP_TEMP_MAX, > >> POWER_SUPPLY_PROP_HEALTH, > >> + POWER_SUPPLY_PROP_TECHNOLOGY, > >> POWER_SUPPLY_PROP_CURRENT_NOW, > >> POWER_SUPPLY_PROP_CURRENT_AVG, > >> }; > >> @@ -296,6 +297,9 @@ static int max17042_get_property(struct power_supply *psy, > >> if (ret < 0) > >> return ret; > >> break; > >> + case POWER_SUPPLY_PROP_TECHNOLOGY: > >> + val->intval = POWER_SUPPLY_TECHNOLOGY_LION; > > > > How can you be sure it is always Li-Ion? For wearables and mobiles, rather yes, but > > the driver is also used in other devices. Technically, specs are saying > > it might be used also with Li-Poly applications. > > I suppose that there is no way to detect this. Would it be ok if I add > an optional Device Tree property that allows to specify if it's Li-Ion > or Li-Poly? If the property is not supplied, then "unknown" is returned. I am not sure in such case what will be the benefit of exposing this to user-space... but it won't harm neither and sounds like a valid usage of DT properties. Fine with me. Best regards, Krzysztof