From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751344AbbD3Hz3 (ORCPT ); Thu, 30 Apr 2015 03:55:29 -0400 Received: from mailout4.samsung.com ([203.254.224.34]:59206 "EHLO mailout4.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750717AbbD3HzZ (ORCPT ); Thu, 30 Apr 2015 03:55:25 -0400 X-AuditID: cbfee690-f796f6d000005054-60-5541dfebeb81 Message-id: <5541DFEA.8060109@samsung.com> Date: Thu, 30 Apr 2015 16:55:22 +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: Roger Quadros Cc: Peter Chen , Robert Baldyga , "Ivan T. Ivanov" , "Balbi, Felipe" , "ABRAHAM, KISHON VIJAY" , 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> <552F724A.1050500@samsung.com> <5541DAA0.7030200@ti.com> In-reply-to: <5541DAA0.7030200@ti.com> Content-type: text/plain; charset=windows-1252 Content-transfer-encoding: 7bit X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFtrCIsWRmVeSWpSXmKPExsWyRsSkWPf1fcdQg3lH+CwO3q+3mH/kHKvF s4kPGS0uPO1hs7i8aw6bxaJlrcwWa4/cZbe43biCzeLY7L9MFg8O72S36Hmk5cDt8e9wP5PH pv3TmD36tqxi9Dh+YzuTx+dNcgGsUVw2Kak5mWWpRfp2CVwZ7fOXsBZsF6u4sXIHSwPjQ8Eu Rk4OCQETiRf7+tkhbDGJC/fWs4HYQgJLGSWermeHqXnUtYC1i5ELKL6IUeLyu69QzgNGieVT HjKDVPEKaEms37oVzGYRUJV43fafCcRmA4rvf3EDbKqoQJjEyulXWCDqBSV+TL4HZosIKErc WwmymYuDWeAKk8Te6+1AGzg4hAV8JBbegFq2illi/f/XjCANnAJqEs9anjKC1DAL6Encv6gF EmYWkJfYvOYtM0i9hMBLdolpz6ezQxwkIPFt8iEWkHoJAVmJTQeYIT6TlDi44gbLBEaxWUhO moUwdRaSqQsYmVcxiqYWJBcUJ6UXmegVJ+YWl+al6yXn525iBEbm6X/PJuxgvHfA+hCjAAej Eg/vh3bHUCHWxLLiytxDjKZAR0xklhJNzgfGf15JvKGxmZGFqYmpsZG5pZmSOO9rqZ/BQgLp iSWp2ampBalF8UWlOanFhxiZODilGhiDs+ZtLCmQO23xSva0h9vtVeZp00NlYjZKbypQn2hr 5abVcOyM5es/Zdfs623jLNQZ/hRtrX+a84NZ3uDPSb+VfmcF9v8MVGrbLNtXyiax2qNEbnf7 DoeGn99/us3bqbi4yHqm/nGlGe881+VUfU4Lj9laPU0yeSXr47D3ntwJ9uen3XzeuVeJpTgj 0VCLuag4EQD5x1XhxwIAAA== X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFvrPIsWRmVeSWpSXmKPExsVy+t9jAd3X9x1DDeZO4bA4eL/eYv6Rc6wW zyY+ZLS48LSHzeLyrjlsFouWtTJbrD1yl93iduMKNotjs/8yWTw4vJPdoueRlgO3x7/D/Uwe m/ZPY/bo27KK0eP4je1MHp83yQWwRjUw2mSkJqakFimk5iXnp2TmpdsqeQfHO8ebmhkY6hpa WpgrKeQl5qbaKrn4BOi6ZeYAXaakUJaYUwoUCkgsLlbSt8M0ITTETdcCpjFC1zckCK7HyAAN JKxhzGifv4S1YLtYxY2VO1gaGB8KdjFyckgImEg86lrACmGLSVy4t56ti5GLQ0hgEaPE5Xdf WSGcB4wSy6c8ZAap4hXQkli/dSuYzSKgKvG67T8TiM0GFN//4gYbiC0qECaxcvoVFoh6QYkf k++B2SICihL3VkJsYBa4wiSx93o70AYODmEBH4mFN6CWrWKWWP//NSNIA6eAmsSzlqeMIDXM AnoS9y9qgYSZBeQlNq95yzyBUWAWkhWzEKpmIalawMi8ilE0tSC5oDgpPddIrzgxt7g0L10v OT93EyM48p9J72Bc1WBxiFGAg1GJh/dDu2OoEGtiWXFl7iFGCQ5mJRHejltAId6UxMqq1KL8 +KLSnNTiQ4ymwACYyCwlmpwPTEp5JfGGxiZmRpZG5oYWRsbmSuK8c3TlQoUE0hNLUrNTUwtS i2D6mDg4pRoYe3oOJnZuNVikc5XNPafnkkCstYPxy9PacnN+b/j+hsOzNa5VMFSwb9/NKX3v t9hpHz36POqwc3KF0ie+is8t6U/6whbEvK2N4hJ/uSNq3cV/G9zPdGUqtpdL8/7f7Dk19PoK 3WMOywJvrHJ4POdSQJzOruQwwWtrjms1idxKPRhVda3vRMpLJZbijERDLeai4kQABT+GRhID AAA= 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 04/30/2015 04:32 PM, Roger Quadros wrote: > On 16/04/15 11:26, Chanwoo Choi wrote: >> 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. >> >> > Chanwoo, Robert, > Hi Roger, > Do we have an agreement on a common solution then? Yes. > IMO the above mentioned 4 notifier events should meet all our USB needs. I'll support usb notifier chain which includes 4 notifier events. Thanks, Chanwoo Choi