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=-4.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 D0662C433E2 for ; Thu, 3 Sep 2020 08:13:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 97FCA2098B for ; Thu, 3 Sep 2020 08:13:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=baylibre-com.20150623.gappssmtp.com header.i=@baylibre-com.20150623.gappssmtp.com header.b="GtDSyPl2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727794AbgICIMP (ORCPT ); Thu, 3 Sep 2020 04:12:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32840 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728374AbgICICR (ORCPT ); Thu, 3 Sep 2020 04:02:17 -0400 Received: from mail-ed1-x543.google.com (mail-ed1-x543.google.com [IPv6:2a00:1450:4864:20::543]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 76818C061244 for ; Thu, 3 Sep 2020 01:02:16 -0700 (PDT) Received: by mail-ed1-x543.google.com with SMTP id l21so1707212eds.7 for ; Thu, 03 Sep 2020 01:02:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=baylibre-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=JoS2/A2+Ww3IX91pPfvlBLGrHGHe5u0F025DKq6wW1w=; b=GtDSyPl2VbQ4Mgc7IUQpzqCJ5s4MzCyCkiJ7snLIkM3C/r4BeMjJh/hyxjxSDgXpTU 46DSuOTgXGmqKSSHrQSh/I4JEoGfmbALzWqgrdGcSDlk1kYkZIKxT3zzu+mZXIpRlU9Z SRR3ZHcRtuIfOBEpqgJ8ZeakqLguUf+apF9QKGAi7VSfTmLIEUwUZ05BqMK0aroQhWKZ E4r9bM8wROHsksaKchb29bweZyNZ8L3GdC7b935Q9gQ8mMsROVq2RDuDR19pmiK4/9CC tul9hVs8lmh4LvqvKSmiiiauSz1CdM0Ez5N3aq+pF24lZQr9QT5ZrtX7K3827zTmc9hx V+Qg== 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=JoS2/A2+Ww3IX91pPfvlBLGrHGHe5u0F025DKq6wW1w=; b=ltWogqPLQxuvWNKo+AyQFaEdFQ97zcydR1ZQNAGHvzVosOsFV/LLTNUSMZAflUmJFu adKEsnMmtalVcYgEnrB/dwjV+3rjN0c2GsCIfQPMYpvNqqWvYXWRhRAV8sAiDDWFGsbv RgPR4lh6yfN9x8oGB3yuYoaV2z8xA761o/yae9c6jNN32CG4XES6JXn5rHcoEypXro0Q enzQKikJjNbs7HW0Mr/Oqj2HM/be7ye1wqhWcKCcP8DrdO559GDt6oO3Z0VaPrywcglH bXTIwFRshnPeSKeccRmRMUqZYFBakAI5GCt6l5iXNO9yP3CcNOc9dfV5l5IeE+eZRIcw XkUg== X-Gm-Message-State: AOAM531lawRhoYFk4XgLsH0ddls0ebE3XvGLJD/p1TQ/SDR4gQnMKSoX l0vSNUGTAPnvI7Gp4ikBv2YwKMnPtC2fTOSA+Om91AyrH9OAOg== X-Google-Smtp-Source: ABdhPJxCL9rkBDqf6nmNxtZ3yPadCzH+wpuSwZjFsxcf1IstXb0QFZGoq7p6IKWO691zAszcGneTZeA2Bcd246Tu9yU= X-Received: by 2002:a05:6402:10d7:: with SMTP id p23mr1730706edu.388.1599120135045; Thu, 03 Sep 2020 01:02:15 -0700 (PDT) MIME-Version: 1.0 References: <20200831032006.1019978-1-warthog618@gmail.com> In-Reply-To: <20200831032006.1019978-1-warthog618@gmail.com> From: Bartosz Golaszewski Date: Thu, 3 Sep 2020 10:02:04 +0200 Message-ID: Subject: Re: [PATCH v6 00/20] gpio: cdev: add uAPI v2 To: Kent Gibson Cc: LKML , linux-gpio , Linus Walleij Content-Type: text/plain; charset="UTF-8" Sender: linux-gpio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org On Mon, Aug 31, 2020 at 5:21 AM Kent Gibson wrote: > > This patchset defines and implements a new version of the > GPIO CDEV uAPI to address existing 32/64-bit alignment issues, add > support for debounce, event sequence numbers, and allow for requested > lines with different configurations. > It provides some future proofing by adding optional configuration fields > and padding reserved for future use. > > The series can be partitioned into three blocks; the first two patches > are minor fixes that impact later patches, the next eleven contain the > v2 uAPI definition and implementation, and the final seven port the GPIO > tools to the v2 uAPI and extend them to use new uAPI features. > > The more complicated patches include their own commentary where > appropriate. > > Cheers, > Kent. > > Changes for v6: > - flags variable in linereq_create() should be u64 not unsigned long > (patch 07) > - remove restrictions on configuration changes - any change from one > valid state to another valid state is allowed. (patches 09, 10, 12) > > Changes for v5: > > All changes for v5 fix issues with the gpiolib-cdev.c implementation, > in patches 07-12. > The uAPI is unchanged from v4, as is the port of the tools. > > - use IS_ALIGNED in BUILD_BUG_ON checks (patch 07) > - relocate BUILD_BUG_ON checks to gpiolib_cdev_register (patch 07) > - s/requies/requires/ (patch 07) > - use unsigned int for variables that are never negative > - change lineinfo_get() parameter from cmd to bool watch (patch 08) > - flagsv2 in gpio_v2_line_info_to_v1() should be u64, not int (patch 08) > - change "_locked" suffixed function names to "_unlocked" (patch 10 and > 11) > - be less eager breaking long lines > - move commentary into checkin comment where appropriate - particularly > patch 12 > - restructure the request/line split - rename struct line to > struct linereq, and struct edge_detector to struct line, and relocate > the desc field from linereq to line. The linereq name was selected > over line_request as function names such as linereq_set_values() are > more clearly associated with requests than line_request_set_values(), > particularly as there is also a struct line. And linereq is as > informative as linerequest, so I went with the shortened form. > > Changes for v4: > - bitmap width clarification in gpiod.h (patch 04) > - fix info offset initialisation bug (patch 08 and inserting patch 01) > - replace strncpy with strscpy to remove compiler warnings > (patch 08 and inserting patch 02) > - fix mask handling in line_get_values (patch 07) > > Changes for v3: > - disabling the character device from the build requires EXPERT > - uAPI revisions (see patch 02) > - replace padding_not_zeroed with calls to memchr_inv > - don't use bitops on 64-bit flags as that doesn't work on BE-32 > - accept first attribute matching a line in gpio_v2_line_config.attrs > rather than the last > - rework lsgpio port to uAPI v2 as flags reverted to v1 like layout > (since patch v2) > - swapped patches 17 and 18 to apply debounce to multiple monitored > lines > > Changes for v2: > - split out cleanup patches into a separate series. > - split implementation patch into a patch for each ioctl or major feature. > - split tool port patch into a patch per tool. > - rework uAPI to allow requested lines with different configurations. > > Kent Gibson (20): > gpiolib: cdev: desc_to_lineinfo should set info offset > gpiolib: cdev: replace strncpy with strscpy > gpio: uapi: define GPIO_MAX_NAME_SIZE for array sizes > gpio: uapi: define uAPI v2 > gpiolib: make cdev a build option > gpiolib: add build option for CDEV v1 ABI > gpiolib: cdev: support GPIO_V2_GET_LINE_IOCTL and > GPIO_V2_LINE_GET_VALUES_IOCTL > gpiolib: cdev: support GPIO_V2_GET_LINEINFO_IOCTL and > GPIO_V2_GET_LINEINFO_WATCH_IOCTL > gpiolib: cdev: support edge detection for uAPI v2 > gpiolib: cdev: support GPIO_V2_LINE_SET_CONFIG_IOCTL > gpiolib: cdev: support GPIO_V2_LINE_SET_VALUES_IOCTL > gpiolib: cdev: support setting debounce > gpio: uapi: document uAPI v1 as deprecated > tools: gpio: port lsgpio to v2 uAPI > tools: gpio: port gpio-watch to v2 uAPI > tools: gpio: rename nlines to num_lines > tools: gpio: port gpio-hammer to v2 uAPI > tools: gpio: port gpio-event-mon to v2 uAPI > tools: gpio: add multi-line monitoring to gpio-event-mon > tools: gpio: add debounce support to gpio-event-mon > > drivers/gpio/Kconfig | 29 +- > drivers/gpio/Makefile | 2 +- > drivers/gpio/gpiolib-cdev.c | 1273 +++++++++++++++++++++++++++++++++-- > drivers/gpio/gpiolib-cdev.h | 15 + > drivers/gpio/gpiolib.c | 5 + > drivers/gpio/gpiolib.h | 6 + > include/uapi/linux/gpio.h | 316 ++++++++- > tools/gpio/gpio-event-mon.c | 146 ++-- > tools/gpio/gpio-hammer.c | 56 +- > tools/gpio/gpio-utils.c | 127 ++-- > tools/gpio/gpio-utils.h | 50 +- > tools/gpio/gpio-watch.c | 16 +- > tools/gpio/lsgpio.c | 60 +- > 13 files changed, 1871 insertions(+), 230 deletions(-) > > > base-commit: feeaefd378cae2f6840f879d6123ef265f8aee79 > -- > 2.28.0 > To me it looks good, just a couple nits here and there and some questions. I think it's worth deciding whether we want to keep the selftests in tools/testing/selftests/gpio/ and then maybe consider porting gpio-mockup-chardev.c to V2 or simply outsource it entirely to libgpiod. Bartosz