From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C6AC7C282CE for ; Tue, 4 Jun 2019 09:20:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A655C24BB7 for ; Tue, 4 Jun 2019 09:20:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727038AbfFDJU7 (ORCPT ); Tue, 4 Jun 2019 05:20:59 -0400 Received: from mail-lj1-f193.google.com ([209.85.208.193]:43307 "EHLO mail-lj1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726937AbfFDJU7 (ORCPT ); Tue, 4 Jun 2019 05:20:59 -0400 Received: by mail-lj1-f193.google.com with SMTP id 16so5369947ljv.10; Tue, 04 Jun 2019 02:20:57 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=shrvH0MPTIPtPrvxwpvqufz6jbMn/DgwchiR9AreY8o=; b=nF6rw02PaJIMuAaGTQ1fiaYwAWBkgsbWCpidsXryrE76WE3Im+fkLi34GYineEwEno n4edIz7TpDbY5Er5hr1WRBoMFZXFOOwcDynpByh9g2Y98YeLSLGvBeMEg5WX+UmpvjR+ PxSGUCLVz8xFkhxTNqdBP3thyxSdKMyIWef/VRJYtXtRP8NxsAgyhtjCV6OV44uCr03C taP+dBE2ZKNnNoVRWIIJOc0cXoDmMLEJB0OwwhsL5ntw1EcA/AmYrebprrjuIcQo3t0m NzjEcClOVzseLXKMucdBFh1GEdJnvNaYWi/xGb1udrbQRz4N9n3M67LTUhbD2g6Ae0yT VWEA== X-Gm-Message-State: APjAAAXD7Kry5gHAUQ3LRRZqH2dPkVdc5+hR0m/0By1yNunZtMs2JaBF 9dp2OxTUb4PF+t7Q+QiII1AiRcDst/DD2QKgDAM= X-Google-Smtp-Source: APXvYqx+rrWhbvZY30REEmyxt6mT0DUhc5dVnLYolEzZwzRG0rP0nqr10EM5C403HoW3KHZiv/xhq5BKHRFFudFQicc= X-Received: by 2002:a2e:2b8d:: with SMTP id r13mr3694725ljr.145.1559640056008; Tue, 04 Jun 2019 02:20:56 -0700 (PDT) MIME-Version: 1.0 References: <20190513152857.13122-1-geert+renesas@glider.be> In-Reply-To: <20190513152857.13122-1-geert+renesas@glider.be> From: Geert Uytterhoeven Date: Tue, 4 Jun 2019 11:20:44 +0200 Message-ID: Subject: Re: [PATCH 00/11] pinctrl: sh-pfc: Convert to new non-GPIO helper macros To: Geert Uytterhoeven Cc: Linus Walleij , Laurent Pinchart , =?UTF-8?Q?Niklas_S=C3=B6derlund?= , Chris Paterson , Linux-Renesas , "open list:GPIO SUBSYSTEM" Content-Type: text/plain; charset="UTF-8" Sender: linux-renesas-soc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-renesas-soc@vger.kernel.org On Mon, May 13, 2019 at 5:29 PM Geert Uytterhoeven wrote: > On many Renesas ARM SoCs, there exist pins that are not associated with > a GPIO port, but still need configuration (e.g. drive strength or > pull-up). While pins with GPIO functionality are indexed by their > GPIO number, no such number exists for non-GPIO pins. Hence for the > latter, the pin control driver uses numbers outside the GPIO number > space, derived from the row and column numbers of the physical pins. > > For R-Car H3 (and later M3-W and M3-N), the choice was made to use the > SiP (System-in-Package, i.e. SoC + RAM + HyperFlash in a BGA package) > physical pin numbers, as the SiP was what was mounted on the > Salvator-X(S) and ULCB development boards available at that time. > > In hindsight, it would have been better to settle on the SoC physical > pin numbers, though: the pin control driver for R-Car M3-W was reused > for the RZ/G2M SoC, which is only available as an SoC, not SiP, thus > making it hard to match the driver with the documentation. > > But even for SoCs there can be confusion: several SoCs are available in > multiple packages, with the same or different number of pins, leading to > different pin numberings. > > As this numbering is used only internal to the driver, and pin control > configuration from DT refers to these pins by signal name, not pin > number (usually, see exceptions below[*]), I started wondering if we > could get rid of the SoC/SiP pin numbers instead. As the actual numbers > don't matter, all that is needed for the driver is a unique number for > each pin. > > Hence this patch series converts the affected drivers to use new macros > that allow to describe pins without GPIO functionality, and refer to > them by auto-generated symbolic enum values, similar in spirit to the > existing scheme for handling pins with GPIO functionality. > > This series consists of three parts: > - Patch 1 introduces new macros to describe and handle pins without > GPIO functionality, > - Patches 2-10 convert the pin control drivers for the individual SoCs > to use the new macros, > - Patch 11 removes the now unused old macros. > > There should be no functional changes induced by this patch series, > which has been tested on Salvator-X(S) (with R-Car H3 ES1.0 and ES2.0, > M3-W, and M3-N), Ebisu (R-Car E3), and KZM-A9-GT (SH-Mobile AG5). > > [*] The user-visible names of pins without GPIO functionality are based > on pin numbers (e.g. "B25") instead of signal names ("CLKOUT") on > EMMA Mobile EV2, R-Car M1A, R-Car H2, and SH-Mobile AG5. > I didn't change these to preserve DT backwards compatibility. Queueing in sh-pfc-for-v5.3. > The "name" parameters of the PIN_NOGP_CFG() and PIN_NOGP() macros could > be removed, if these macros would generate the names from the "pin" > parameters. However, that would: > 1. Require replacing the "#" suffices in pin names for active-low > signals by "_N", > R-Car H3/M3-W/M3-N use a "#" suffix, R-Car E3 use a "_N" suffix. > 2. Replace the names based on pin numbers on older SoCs by signal > names. > Both changes could affect DT backwards compatibility. None of these are > currently used in (upstream) DTS files, though. > Do you think it would be worthwhile to make this consistent? We can still break backwards compatibility later ;-) Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds