From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757075AbbDPI1B (ORCPT ); Thu, 16 Apr 2015 04:27:01 -0400 Received: from mailout2.samsung.com ([203.254.224.25]:13165 "EHLO mailout2.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753473AbbDPI0x (ORCPT ); Thu, 16 Apr 2015 04:26:53 -0400 X-AuditID: cbfee690-f796f6d000005054-e1-552f724a4442 Message-id: <552F724A.1050500@samsung.com> Date: Thu, 16 Apr 2015 17:26:50 +0900 From: Chanwoo Choi User-Agent: Mozilla/5.0 (X11; Linux i686; rv:17.0) Gecko/20130106 Thunderbird/17.0.2 MIME-version: 1.0 To: Peter Chen Cc: "Ivan T. Ivanov" , "Balbi, Felipe" , "ABRAHAM, KISHON VIJAY" , Roger Quadros , Robert Baldyga , myungjoo.ham@samsung.com, linux-usb@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, m.szyprowski@samsung.com Subject: Re: [PATCH v3 2/4] extcon: usb-gpio: add support for VBUS detection References: <552CEC97.1050205@samsung.com> <552CEE42.1050907@ti.com> <552CFA1E.5070400@samsung.com> <20150415032734.GA29095@shlinux2> <552E1862.6090709@ti.com> <552E2EBF.5090906@samsung.com> <20150416015922.GB22269@shlinux2> <552F5E17.5020902@samsung.com> <1429168424.26621.1.camel@mm-sol.com> <552F6BE3.5080604@samsung.com> <20150416080107.GC1709@shlinux2> In-reply-to: <20150416080107.GC1709@shlinux2> Content-type: text/plain; charset=ISO-8859-1 Content-transfer-encoding: 7bit X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFtrGIsWRmVeSWpSXmKPExsWyRsSkQNerSD/UYMM/U4uD9+st5h85x2rx bOJDRosLT3vYLC7vmsNmsWhZK7PF2iN32S1uN65gszg2+y+TxYPDO9kteh5pOXB7/Dvcz+Sx af80Zo++LasYPY7f2M7k8XmTXABrFJdNSmpOZllqkb5dAlfG5pbqgktCFW8vtDI2MF7m62Lk 5JAQMJF4e/87K4QtJnHh3nq2LkYuDiGBpYwSrX9/scMU/f5xESoxnVHi1ozTUM4DRokThzcw g1TxCmhJnP39EGwUi4CqxJfb08FsNqD4/hc32EBsUYEwiZXTr7BA1AtK/Jh8D8wWEdCUWHf+ GBPIUGaBU0wSyzpXASU4OIQFfCQW3mCFWPaeSeLjwkawQZwCuhLnZq0DW8wsoCOxv3UaG4Qt L7F5zVtmkAYJgUfsEmf2QlzHIiAg8W3yIbChEgKyEpsOMEO8JilxcMUNlgmMYrOQ3DQLydhZ SMYuYGRexSiaWpBcUJyUXmSiV5yYW1yal66XnJ+7iREYnaf/PZuwg/HeAetDjAIcjEo8vD9S 9EOFWBPLiitzDzGaAl0xkVlKNDkfmALySuINjc2MLExNTI2NzC3NlMR5X0v9DBYSSE8sSc1O TS1ILYovKs1JLT7EyMTBKdXAOLFVmX2PqV+ItUt7ptpnnsurTt8V/Z947bXqY/mc3zIvkhf0 WrkyvExK1Sl1NRA4evpl7zwWNjmpXR9crm9grtx0TrJo+0yp7wzWKd9TXydaeW87/fFN46qm bU83zufRZFb0veGwu1ZT1WL/lROKZat8Yv8IP+qLLg3sXr3I9T+D5LfollolJZbijERDLeai 4kQA2alLU8kCAAA= X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFmpgleLIzCtJLcpLzFFi42I5/e+xoK5XkX6owfwGPYuD9+st5h85x2rx bOJDRosLT3vYLC7vmsNmsWhZK7PF2iN32S1uN65gszg2+y+TxYPDO9kteh5pOXB7/Dvcz+Sx af80Zo++LasYPY7f2M7k8XmTXABrVAOjTUZqYkpqkUJqXnJ+SmZeuq2Sd3C8c7ypmYGhrqGl hbmSQl5ibqqtkotPgK5bZg7QZUoKZYk5pUChgMTiYiV9O0wTQkPcdC1gGiN0fUOC4HqMDNBA whrGjM0t1QWXhCreXmhlbGC8zNfFyMkhIWAi8fvHRTYIW0ziwr31QDYXh5DAdEaJWzNOQzkP GCVOHN7ADFLFK6Alcfb3Q1YQm0VAVeLL7elgNhtQfP+LG2CTRAXCJFZOv8ICUS8o8WPyPTBb REBTYt35Y0wgQ5kFTjFJLOtcBZTg4BAW8JFYeIMVYtl7JomPCxvBBnEK6Eqcm7UObDGzgI7E /tZpbBC2vMTmNW+ZJzAKzEKyYxaSsllIyhYwMq9iFE0tSC4oTkrPNdQrTswtLs1L10vOz93E CI79Z1I7GFc2WBxiFOBgVOLh/ZGiHyrEmlhWXJl7iFGCg1lJhPd4OlCINyWxsiq1KD++qDQn tfgQoykwCCYyS4km5wPTUl5JvKGxiZmRpZG5oYWRsbmSOO8cXblQIYH0xJLU7NTUgtQimD4m Dk6pBsYYmynr3zGdr/XjYAhOONyqNP+kU/xb3s4vC0MdLfWuqT/aelmO69ux5OtLs9YeaV+7 729w/P/Zx75L73RRE8hZw7JAtutJm9jDW9/FHp4R36ouwGIk0XfE9dC6R/vn/PYV3S/3wrPs 2NKO47/vZHp9WCJ5u/Gj2+obKaFFfhm3V3nnySzk/dyoxFKckWioxVxUnAgALL8dkxMDAAA= DLP-Filter: Pass X-MTR: 20000000000000000@CPGS X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/16/2015 05:01 PM, Peter Chen wrote: > On Thu, Apr 16, 2015 at 04:59:31PM +0900, Chanwoo Choi wrote: >> On 04/16/2015 04:13 PM, Ivan T. Ivanov wrote: >>> Hi, >>> >>> On Thu, 2015-04-16 at 16:00 +0900, Chanwoo Choi wrote: >>>> Hi Peter, >>>> >>>> On 04/16/2015 10:59 AM, Peter Chen wrote: >>>>> >>> >>>>> Ok, from USB point, external id/vbus value can't decide >>>>> which role the controller will be, the controller driver >>>>> will decide role according to many things, eg, user configurations, >>>>> id/vbus value, OTG HNP, etc. >>>>> >>>>> So, from USB controller/phy driver, it doesn't care which cable is >>>>> inserted, it cares about id/vbus value. Eg, it can get id/vbus value >>>>> and it will be notified when the id/vbus value has changed. >>>> >>>> OK, I change the notifier name and add notifier events as following: >>>> >>>> - extcon_{register|unregister}_usb_notifier(struct extcon_dev *edev, struct notifier_block *nb); >>>> - list of notifier events >>>> #define EXTCON_USB_ID_L_VBUS_L0 /* ID low and VBUS low */ >>>> #define EXTCON_USB_ID_L_VBUS_H1 /* ID low and VBUS high */ >>>> #define EXTCON_USB_ID_H_VBUS_L2 /* ID high and VBUS low */ >>>> #define EXTCON_USB_ID_H_VBUS_H3 /* ID high and VBUS high */ >>> >>> I am still confused, why we mix ID and VBUS events into one? >>> Those are two lines and they are not necessarily handled by >>> the same extcon_dev. >> >> IMO, if some usb driver check both id and vbus pin at the same time, >> the usb driver can know the both id and vbus pin state through only one notifier event. >> >> Also, >> If some usb driver want to know the state of id pin except of vbus state, >> when receiving following events, id pin is low. >> #define EXTCON_USB_ID_L_VBUS_L0 >> #define EXTCON_USB_ID_L_VBUS_H1 >> when receiving following events, id pin is high. >> #define EXTCON_USB_ID_H_VBUS_L2 >> #define EXTCON_USB_ID_H_VBUS_H3 >> Also, some usb driver would catch the vbus pin state with same method. >> >> But, it is just my opinion. We may use following notifier events for each pin. >> We need to discuss it. >> #define EXTCON_USB_ID_LOW >> #define EXTCON_USB_ID_HIGH >> #define EXTCON_USB_VBUS_LOW >> #define EXTCON_USB_VBUS_HIGH >> > > I agree with above definition. > OK. I understand.