From patchwork Fri Dec 29 09:33:27 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kent Gibson X-Patchwork-Id: 758883 Received: from mail-pj1-f50.google.com (mail-pj1-f50.google.com [209.85.216.50]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 77F2510A00 for ; Fri, 29 Dec 2023 09:33:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="A2HjGQ9W" Received: by mail-pj1-f50.google.com with SMTP id 98e67ed59e1d1-28c075ad8e7so4587309a91.2 for ; Fri, 29 Dec 2023 01:33:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1703842431; x=1704447231; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=9//bAFoz6vEI5nCZG+2mrTfj4Z29wGMt2kFPQl4urQ0=; b=A2HjGQ9WkO9TbrRDHfVys/Tzt3qESnijnb+3cYmCpMGqCGqnIZE88jnPtO2TmX22IV n4PaVcO6fZCqV+8tyhuCcEMSv6eFhMbO1MV8xxiOYJTsmdWxLnQd0QuiDbyFI/ftIFKl iYR6INU856AIEWo1cbUpu4wsFFkyDkmFuJ2CbJ4zj+o2PIQHilUvlDdD00BDrXiQy9eQ 5BUBo3yOk7jJ3YQ5jue8Nq8tjKCcwJYFL8GxdIhU9y6/UjVNKr6W7/tZjYEOXzfV2f9t KgC4P1R3h4CPLfENy/2UarLvC5veEbPt7W6xqbwfLOBru1sAtYb8yjovbp44ZmgYb4eS WUYQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1703842431; x=1704447231; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=9//bAFoz6vEI5nCZG+2mrTfj4Z29wGMt2kFPQl4urQ0=; b=LPzJEPppA1DOr8T/nHmZqGiR8J6os8qJSS9Qmd8lepP1nnN7y+IKc1Gj9QOr2tjTKI ElQ1MrS9ehYzve0aqBCnbacAMZCVwwT7l9ndfDunc6jg8C0mtiAhUvLLbq5MO/jzXrL7 9c54aGeQuEt6mIEaHvb3oci2EEJBsH+Mt0xAFdWJz52n3YsyExDzY8dEE2mdJCmPoDWi HDOmvReXXX7wMv1Tgi0rZ3UGi6Zk+/YSVROhsU9IEQe0X25zMNmTt6tVfVJsGXBSYJN8 Vyp3Kp960Qq53NS/9hbFkAJcRtVwevDqsHtT0J3IJLNQscSJSm5GiF7aYdyr5gVHCPX8 zi8w== X-Gm-Message-State: AOJu0Yx1ouVnpe+mdgCcHuIi8W3qS8eWluh/BNkaDO6lMWcJlBczTtIQ RqhFlh/8RFm4g9kUG/yoQricBdKi8WQ= X-Google-Smtp-Source: AGHT+IEJM/6MwoG/5mqW58tTMSO2QV7jSYY0WdXCxThQsMol1lElWSkhKsuDKzE5nXl9hAGvUH9StA== X-Received: by 2002:a17:90a:9307:b0:28c:7a2c:c690 with SMTP id p7-20020a17090a930700b0028c7a2cc690mr3579139pjo.7.1703842431713; Fri, 29 Dec 2023 01:33:51 -0800 (PST) Received: from rigel.home.arpa (60-241-235-125.tpgi.com.au. [60.241.235.125]) by smtp.gmail.com with ESMTPSA id pi15-20020a17090b1e4f00b0028be1aec1b6sm15600907pjb.52.2023.12.29.01.33.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 29 Dec 2023 01:33:51 -0800 (PST) From: Kent Gibson To: linux-gpio@vger.kernel.org, brgl@bgdev.pl Cc: Kent Gibson Subject: [libgpiod][PATCH v2 1/2] gpioset: reword note on post-exit behaviour Date: Fri, 29 Dec 2023 17:33:27 +0800 Message-Id: <20231229093328.62366-2-warthog618@gmail.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20231229093328.62366-1-warthog618@gmail.com> References: <20231229093328.62366-1-warthog618@gmail.com> Precedence: bulk X-Mailing-List: linux-gpio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The note regarding the state of a line after gpioset exits is confusing and unhelpful to the average reader, if not outright incorrect. A common mis-interpretation is that this behaviour is arbitrarily chosen by spiteful implementors. The note also specifies that the line reverts to default, but that is not always the case, or is at least out of the control of gpioset or libgpiod. Reword the note to constrain the scope to that relevant to the likely reader, and to emphasize that the behaviour is inherent in the kernel GPIO interface, not in the gpioset implementation. Signed-off-by: Kent Gibson --- tools/gpioset.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/tools/gpioset.c b/tools/gpioset.c index 9dc5aeb..f2f9a15 100644 --- a/tools/gpioset.c +++ b/tools/gpioset.c @@ -76,11 +76,10 @@ static void print_help(void) print_period_help(); printf("\n"); printf("*Note*\n"); - printf(" The state of a GPIO line controlled over the character device reverts to default\n"); - printf(" when the last process referencing the file descriptor representing the device file exits.\n"); - printf(" This means that it's wrong to run gpioset, have it exit and expect the line to continue\n"); - printf(" being driven high or low. It may happen if given pin is floating but it must be interpreted\n"); - printf(" as undefined behavior.\n"); + printf(" It should not be assumed that a line will retain its state after gpioset exits.\n"); + printf(" When a process exits, any GPIO lines it has requested are automatically released.\n"); + printf(" Once released, the state of a line may be modified by the kernel or another process.\n"); + printf(" To guarantee the requested value, by default gpioset does not exit.\n"); } static int parse_drive_or_die(const char *option) From patchwork Fri Dec 29 09:33:28 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kent Gibson X-Patchwork-Id: 760078 Received: from mail-pf1-f179.google.com (mail-pf1-f179.google.com [209.85.210.179]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F1A9B10A00 for ; Fri, 29 Dec 2023 09:34:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="XWOjniMX" Received: by mail-pf1-f179.google.com with SMTP id d2e1a72fcca58-6d9bee259c5so1429151b3a.1 for ; Fri, 29 Dec 2023 01:34:01 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1703842441; x=1704447241; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=8vS0Wn45sps+TwL3iN7GzIBr4cClZFxKj71HYPN1OV8=; b=XWOjniMXz27sYdOnMvVrfaNvWQu/RaRiS8GzwT+jO9RnEifkERSWp8+kpys8Aawjss +OKjFf6HLSrR713WsyKXGu2FUyG0uZ88gO7qfPehGzbdNvrZ5I2tvKs67F8DbYh6ivaH 0HWQzd8ctk/HORyjds3O2xJc9ShfIgDxjRWbPqB3lqwe/4dZoC883hFU6ikpVgXUSkIz PT6CFOPKHQO9mfPlxmYIbKH46pNwhsDk3RhPIM0PRZc5GKkE/1NAt9H8q7Yu5BdavZJp j2CbJfoUcTGsZX/TsjqpZzMDI80tYaxan9SmBci+1oAAC0IHgGvUapTI9YYFdOmAEjaY 24dA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1703842441; x=1704447241; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=8vS0Wn45sps+TwL3iN7GzIBr4cClZFxKj71HYPN1OV8=; b=iB2hniugJpQdhfOHJ8pFb+qkAu0t5b7yhgrVUrYGSA2OQQTtYLK5wTivCcx8XqgSQ6 liUGzHenoj7HPJT5gzu3zhNDIxfyfV1NMLfdfsZw+s/39phGzZGCmDvECdUFv0NwRcFt uQBNRrgABqodWYrM3Sg8XW+Jzca0D+c7Cz911OsEoF7lsuG5YntPN2TlSnoSCSsTXeX+ d8jrCGi6WhiQdWekR+ram3stayoTyDPV3rloZHroZk9O1olkqYVrqQBJe+St7AyztW92 bjdmC15lzQf77dti2S6q42EJiumHVqgAjjFhLNkxUQZUmwxeP1n26/qILpDgKZvwAAPo xSBA== X-Gm-Message-State: AOJu0YyPCAocMv5We/vZT74gP9+onJYC0gF9e6vI0jRaSBGpcSJp82AX eT6NH+bqupvg/38biaf9B1otIgjcouQ= X-Google-Smtp-Source: AGHT+IEwOxC5nhpbKQe0gNSU/HkONYN4FE/DVPXEZMsn6aezsLDD8xiy1K1aV/GDvdLbBg8Pz7MtxQ== X-Received: by 2002:a05:6a20:54a8:b0:196:5720:fbba with SMTP id i40-20020a056a2054a800b001965720fbbamr1391160pzk.62.1703842441080; Fri, 29 Dec 2023 01:34:01 -0800 (PST) Received: from rigel.home.arpa (60-241-235-125.tpgi.com.au. [60.241.235.125]) by smtp.gmail.com with ESMTPSA id pi15-20020a17090b1e4f00b0028be1aec1b6sm15600907pjb.52.2023.12.29.01.33.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 29 Dec 2023 01:34:00 -0800 (PST) From: Kent Gibson To: linux-gpio@vger.kernel.org, brgl@bgdev.pl Cc: Kent Gibson Subject: [libgpiod][PATCH v2 2/2] gpioset: improve toggle option help Date: Fri, 29 Dec 2023 17:33:28 +0800 Message-Id: <20231229093328.62366-3-warthog618@gmail.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20231229093328.62366-1-warthog618@gmail.com> References: <20231229093328.62366-1-warthog618@gmail.com> Precedence: bulk X-Mailing-List: linux-gpio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Reword toggle option help to add that a 0 terminated sequence will exit. Signed-off-by: Kent Gibson --- tools/gpioset.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/gpioset.c b/tools/gpioset.c index f2f9a15..863da4a 100644 --- a/tools/gpioset.c +++ b/tools/gpioset.c @@ -68,7 +68,7 @@ static void print_help(void) printf(" -s, --strict\t\tabort if requested line names are not unique\n"); printf(" -t, --toggle [,period]...\n"); printf("\t\t\ttoggle the line(s) after the specified period(s)\n"); - printf("\t\t\tIf the last period is non-zero then the sequence repeats.\n"); + printf("\t\t\tIf the last period is 0 then gpioset exits else the sequence repeats.\n"); printf(" --unquoted\tdon't quote line names\n"); printf(" -v, --version\t\toutput version information and exit\n"); printf(" -z, --daemonize\tset values then detach from the controlling terminal\n");