Return-path: Received: from mail-out.m-online.net ([212.18.0.9]:60095 "EHLO mail-out.m-online.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751699AbdBMGiU (ORCPT ); Mon, 13 Feb 2017 01:38:20 -0500 Subject: Re: [PATCH] Make EN2 pin optional in the TRF7970A driver To: Rob Herring References: <1486444924-18444-1-git-send-email-hs@denx.de> <20170210155114.pvjahqqjqurw5jdc@rob-hp-laptop> Cc: netdev@vger.kernel.org, Guan Ben , Mark Jonas , devicetree@vger.kernel.org, linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org, Samuel Ortiz , Lauro Ramos Venancio , Aloisio Almeida Jr , Mark Rutland From: Heiko Schocher Reply-To: hs@denx.de Message-ID: <58A15454.4030602@denx.de> (sfid-20170213_073903_327971_6326A160) Date: Mon, 13 Feb 2017 07:38:12 +0100 MIME-Version: 1.0 In-Reply-To: <20170210155114.pvjahqqjqurw5jdc@rob-hp-laptop> Content-Type: text/plain; charset=windows-1252; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: Hello Rob, Am 10.02.2017 um 16:51 schrieb Rob Herring: > On Tue, Feb 07, 2017 at 06:22:04AM +0100, Heiko Schocher wrote: >> From: Guan Ben >> >> Make the EN2 pin optional. This is useful for boards, >> which have this pin fix wired, for example to ground. >> >> Signed-off-by: Guan Ben >> Signed-off-by: Mark Jonas >> Signed-off-by: Heiko Schocher >> >> --- >> >> .../devicetree/bindings/net/nfc/trf7970a.txt | 4 ++-- >> drivers/nfc/trf7970a.c | 26 ++++++++++++---------- >> 2 files changed, 16 insertions(+), 14 deletions(-) >> >> diff --git a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt >> index 32b35a0..5889a3d 100644 >> --- a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt >> +++ b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt >> @@ -5,8 +5,8 @@ Required properties: >> - spi-max-frequency: Maximum SPI frequency (<= 2000000). >> - interrupt-parent: phandle of parent interrupt handler. >> - interrupts: A single interrupt specifier. >> -- ti,enable-gpios: Two GPIO entries used for 'EN' and 'EN2' pins on the >> - TRF7970A. >> +- ti,enable-gpios: One or two GPIO entries used for 'EN' and 'EN2' pins on the >> + TRF7970A. EN2 is optional. > > Could EN ever be optional/fixed? If so, perhaps deprecate this property > and do 2 properties, one for each pin. The hardware I have has the EN2 pin fix connected to ground. Looking into http://www.ti.com/lit/ds/slos743k/slos743k.pdf page 19 table 6-3 and 6-4 the EN2 pin is a don;t core if EN = 1. If EN = 0 EN2 pin selects between Power Down and Sleep Mode ... I see no reason why this is not possible/allowed ... Hmm.. I do not like the idea of deprecating the "ti,enable-gpios" property into 2 seperate properties ... but if this would be a reason for not accepting this patch, I can do this ... How should I name the 2 new properties? "ti,pin-enable" and "ti,pin-enable2" ? bye, Heiko -- DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany