From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932271AbcKISN5 (ORCPT ); Wed, 9 Nov 2016 13:13:57 -0500 Received: from mail-out.m-online.net ([212.18.0.9]:56032 "EHLO mail-out.m-online.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753466AbcKISNz (ORCPT ); Wed, 9 Nov 2016 13:13:55 -0500 X-Auth-Info: 9MgdgX0JI3B5VfLQymeBMiZhFROjwBdUmbnD4ee+qaA= Subject: Re: [PATCH v8 3/3] fpga: Add support for Lattice iCE40 FPGAs To: Joel Holdsworth , Moritz Fischer References: <1478486962-26794-1-git-send-email-joel@airwebreathe.org.uk> <1478486962-26794-3-git-send-email-joel@airwebreathe.org.uk> <2255968d-b97c-2b9c-4e4d-7f3717a748e3@denx.de> <01d1a97b-2f43-49a6-51fb-e223ef4dce9b@airwebreathe.org.uk> <4bdba358-db18-48f1-3286-a7a7f4c30215@denx.de> Cc: Alan Tull , Geert Uytterhoeven , Rob Herring , Devicetree List , Linux Kernel Mailing List , linux-spi@vger.kernel.org, Clifford Wolf From: Marek Vasut Message-ID: Date: Wed, 9 Nov 2016 13:01:56 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Icedove/45.4.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/08/2016 06:30 PM, Joel Holdsworth wrote: >>>> On the whole, I don't think the zero-length transfers are too >>>> egregiously bad, and all the alternatives seem worse to me. >>> >>> So why not turn the CS line into GPIO and just toggle the GPIO? >> >> Does that work with *all* SPI controllers? >> > > It does not - no. See my other email. And is that line an actual CS of that lattice chip or a generic input which almost works like CS? -- Best regards, Marek Vasut