Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754271Ab3JDCFw (ORCPT ); Thu, 3 Oct 2013 22:05:52 -0400 Received: from mail-wi0-f173.google.com ([209.85.212.173]:62312 "EHLO mail-wi0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751667Ab3JDCFt (ORCPT ); Thu, 3 Oct 2013 22:05:49 -0400 MIME-Version: 1.0 In-Reply-To: References: <1380670860-17621-1-git-send-email-seanpaul@chromium.org> <1380670860-17621-4-git-send-email-seanpaul@chromium.org> Date: Fri, 4 Oct 2013 11:05:48 +0900 X-Google-Sender-Auth: M5I20QDFcm_u1AM42-Ii8XBB7Q4 Message-ID: Subject: Re: [PATCH 3/5] drm/bridge: Add PTN3460 bridge driver From: Inki Dae To: Olof Johansson Cc: Sean Paul , "devicetree@vger.kernel.org" , "linux-samsung-soc@vger.kernel.org" , "linux-doc@vger.kernel.org" , "linux-kernel@vger.kernel.org" , DRI mailing list , "linux-arm-kernel@lists.infradead.org" Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1645 Lines: 41 2013/10/4 Olof Johansson : > On Thu, Oct 3, 2013 at 10:39 AM, Inki Dae wrote: >> 2013/10/3 Sean Paul : >>> On Thu, Oct 3, 2013 at 9:55 AM, Inki Dae wrote: >>>> Can a regulator be used instead of gpio in other board case? >>>> >>> >>> No, not to my knowledge. >>> >> >> Hm.. plz check it out again. the gpio pin is specific to board, and >> the the gpio be used as power source trigger could be replaced with a >> regulator according to board design. So you should consider all >> possibilities even though there are no other cases yet: other board >> could use a regulator instead. > > Take a look at the data sheet, it is publicly available. > > PD_N is not a power supply input, so modelling it as a regulator makes no sense: > > "If PD_N is LOW, then the device is in Deep power-down completely, > even if supply rail is ON; for the device to be able to operate, the > PD_N pin must be HIGH." > I still think the pin could be replaced with a regulator. But lvds-bridge node has "powerdown-gpio" property - it say this board will use gpio pin - specific to board. So it seems no problem. > > > -Olof > -- > To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/