From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754330AbbFSJuK (ORCPT ); Fri, 19 Jun 2015 05:50:10 -0400 Received: from mail-ie0-f178.google.com ([209.85.223.178]:34391 "EHLO mail-ie0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754178AbbFSJuE (ORCPT ); Fri, 19 Jun 2015 05:50:04 -0400 MIME-Version: 1.0 Reply-To: cw00.choi@samsung.com In-Reply-To: <20150619091349.GU32730@opensource.wolfsonmicro.com> References: <1434638631-16451-1-git-send-email-ckeepax@opensource.wolfsonmicro.com> <1434638631-16451-4-git-send-email-ckeepax@opensource.wolfsonmicro.com> <20150619081433.GR32730@opensource.wolfsonmicro.com> <20150619091349.GU32730@opensource.wolfsonmicro.com> Date: Fri, 19 Jun 2015 18:50:03 +0900 Message-ID: Subject: Re: [PATCH v2 3/5] extcon: arizona: Convert to gpiod From: Chanwoo Choi To: Charles Keepax Cc: Lee Jones , "myungjoo.ham@samsung.com" , Samuel Ortiz , devicetree , linux-kernel , patches@opensource.wolfsonmicro.com Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jun 19, 2015 at 6:13 PM, Charles Keepax wrote: > On Fri, Jun 19, 2015 at 05:39:22PM +0900, Chanwoo Choi wrote: >> On Fri, Jun 19, 2015 at 5:14 PM, Charles Keepax >> wrote: >> > On Fri, Jun 19, 2015 at 11:36:47AM +0900, Chanwoo Choi wrote: >> >> Hi Charles, >> >> >> >> On Thu, Jun 18, 2015 at 11:43 PM, Charles Keepax >> >> wrote: >> >> > Convert to using the newer gpiod interface for the micd_pol_gpio. >> >> > Although we still carry support for the old gpio interface from pdata. >> >> > >> >> > Signed-off-by: Charles Keepax >> >> > --- >> >> > + mode = GPIOD_OUT_HIGH; >> >> > + else >> >> > + mode = GPIOD_OUT_LOW; >> >> > + >> >> > + info->micd_pol_gpio = gpiod_get_optional(arizona->dev, >> >> > + "wlf,micd-pol", >> >> > + GPIOD_OUT_LOW); >> >> >> >> You can use the devm_gpiod_get_optional() to manage the system >> >> resource automatically. >> >> >> > >> > We can't actually use the devm call here, we need to pass >> > arizona->dev as that is where the DT will reside, which is the >> > device for the MFD. But if the devm is attached to the device for >> > the MFD then it will not clear up when the extcon driver is >> > unloaded. As such we have to do the put manually. >> > >> > I will look at respinning for the other comments. >> >> I don't understand. extcon-arizona.c used already following devm_* functions: >> - devm_kzalloc() >> - devm_regulator_get() >> - devm_extcon_dev_*() >> - devm_input_allocate_device() >> - devm_gpio_request_one() > > Yes but if you look at those all of those are against &pdev->dev > which is the extcon device. > > The gpiod interface expects the device passed to both contain > the of_node and be used for the devm operations. But we need to > use the extcon device for the devm operations, but the of_node is > contained on the MFD device. > > So if I do: > > devm_gpiod_get_optional(arizona->dev, .... > > Then the gpiod won't be released when the extcon device is > removed. But if I do: > > devm_gpiod_get_optional(&pdev->dev, .... > > Then it won't be able to find the DT entries. I understand the difference between arizona->dev and &pdev->dev. But, extcon-arizona.c already get the instance of regulator by using devm_regulator_get() with &pdev->dev as following: The devm_regulator_get() can find the DT entry in dts file. info->micvdd = devm_regulator_get(&pdev-dev, "MICVDD"); How did extcon-arizona.c get the instance of regulator throught devm_regulator_get() in dts file?