From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpcmd13147.aruba.it (smtpcmd13147.aruba.it [62.149.156.147]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 171DF14AD17 for ; Thu, 26 Sep 2024 08:50:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=62.149.156.147 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727340608; cv=none; b=U2rRnUjQ1knSlrG6p6ozRe/aOoQ2CKGXQGVX16wa0TuCgCo2r1ZurmGeqtjceALKs8n8Chb0aL9sQVVJ5hrTUMXLHflXLuDjYAw4PKZ4KO/qgIOopJbwsmfuqspdt3XOTt3dpJBYZEfQljKGRLMTITcpVHNP9vLtTvj8JpUODqA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727340608; c=relaxed/simple; bh=4AupH/BviNHtaHpZmQ9S7ipD1OFuKiaMUUbNa6H3IJQ=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=I7aCPALxW1XsssVcYczou7+jPK8RvetCcUFXocOHOsQ/1GEl+TLvCnI9tDfy1NC+tvk89gPX7G5xrPslVhNwrJ7buBEPc/56SKwvn7nekAnPX2pRetwYZSkHOqgS56bM+LjHQ+IfVUMb3wFwjilBjkqIUf/MhH2RGMTLauuv8z4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=enneenne.com; spf=pass smtp.mailfrom=enneenne.com; dkim=pass (2048-bit key) header.d=aruba.it header.i=@aruba.it header.b=OzPmiQbc; arc=none smtp.client-ip=62.149.156.147 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=enneenne.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=enneenne.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=aruba.it header.i=@aruba.it header.b="OzPmiQbc" Received: from [192.168.1.57] ([79.0.204.227]) by Aruba Outgoing Smtp with ESMTPSA id tk9GsxGjg8U42tk9HsMf3E; Thu, 26 Sep 2024 10:46:56 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=aruba.it; s=a1; t=1727340416; bh=4AupH/BviNHtaHpZmQ9S7ipD1OFuKiaMUUbNa6H3IJQ=; h=Date:MIME-Version:Subject:To:From:Content-Type; b=OzPmiQbcYU4Tn8TiRv+eEu4jTjOm+vCSLoKQsHKWwlwjmvqh2y6n7mERYvSKNTCro vr3l0S8kphfyniViG6Ic5bxhkPIr+bB4LKVtjxw/24wH7cU1Ee/lR8A510FcohlgSd aLlTidJqVOkx55UtptgbUZtoGTZLQm/fLP3B7/dOn2kRFuyKNfKtrem+r4LkiNmTfA VbXndxp5XvWK1+fnvslma51qBsC/rZA3UquRfn/FVMydUVtB3SZzPq6Qqg6yNiQwmk vPiCWBCZ88WMD1kGH5EtK53UjAWwchTFuyJeq8VNHfKk1nhu6GWMI6RbcZQNJ3408z xPQCUIxdO5k7A== Message-ID: Date: Thu, 26 Sep 2024 10:46:54 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v12 2/3] Documentation: driver-api: pps: Add Intel Timed I/O PPS generator To: "Hall, Christopher S" Cc: "Mohan, Subramanian" , "tglx@linutronix.de" , "corbet@lwn.net" , "linux-kernel@vger.kernel.org" , "linux-doc@vger.kernel.org" , "andriy.shevchenko@linux.intel.com" , "Dong, Eddie" , "N, Pandith" , "T R, Thejesh Reddy" , "Zage, David" , "Chinnadurai, Srinivasan" , Greg KH References: <20240823070109.27815-1-subramanian.mohan@intel.com> <20240823070109.27815-3-subramanian.mohan@intel.com> <2024082456-kitchen-astride-7892@gregkh> <801c7a93-667b-4c23-9493-4cbe979847a2@enneenne.com> <2024090304-viewing-lavish-c05e@gregkh> From: Rodolfo Giometti Content-Language: en-US In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-CMAE-Envelope: MS4xfMug2r+xb8fM0qHgPmLgkam22qBK9bSW3EXeA1dfwYDwXC3Mp2LaQFKs5Arg1qfTvDxefz5LtFt1wWsN7Z6DM0eqhlfEhqFMV/JhZHjDlfasJQTPH+vq gLGIHG8oGtycnDEVSfAFWdeIZ0eirMwJc2UZXHvhOFG0rBWAeiPdTCptyNy9q+YUlG0gr+q/oUdoOMOkflsO16AevFd0trnw7VAx7AW85CJjaqw9eR+mOk24 +nFvVtMXNEFk9jFpZOK65n9/22PwptVXMcwwccOkt3U6B7UiE5NIkHgHCtgbpDNbTRE6jXZ8xvmAxKWSNWGxNSIlpidYHbfL0iXB5kfS8UZuu7r7cqeTqNqJ N2zsrLXkG6FnyhLfc935uUHwes6QU5mP3024YI0zJ3kc2o9j+MP4/7TRp8VlBXGbqyspuGLLpdoUfvI0azyyzpC1CSpNScJj9HUhLQgAca5O0rUWDWRJoqh0 j015aasJRrn8vRAcKFhRKa5FDXV2WYtEM1QMbWG6CJZJCP+RL2RsiaTP8NOHyt+Vf9OyjEsyTJLEh/lwVo3LCg72IfE8NkqaWGQZ+NUf+AYRUQzFwV3xSi3M +koHSS0/Gx1xtfkwwGMCpJ3juwcAfdRCzap/5k5HKc0JJZm3UFs4eUDVsnzdWaTF+W8= On 25/09/24 23:55, Hall, Christopher S wrote: > Hi Rodolfo, Hello. >> From: Greg KH >> Sent: Tuesday, September 03, 2024 3:25 AM >> To: Rodolfo Giometti > >> Subject: Re: [PATCH v12 2/3] Documentation: driver-api: pps: Add Intel Timed >> I/O PPS generator >> > >>> If you are willing to stop the inclusion due this fact maybe its time to add >>> such PPS generators interface... on the other hand, if you agree for >>> inclusion we can do this job as soon as the code has been included, in order >>> to fix this anomalous status. >> >> Please make a generic pps subsystem for this, it would make it simpler >> for everyone. > > What is required to move this? We can certainly test the code and do some > of this work, but I would look to you to define the interface. The problem is that a pps-generator has no related device, then no sysfs entries. I think the right-thing(TM) to do is adding a new class named "pps-generator", so we will get the directory /sys/class/pps-generator with several devices as pps-generator0, pps-generator1, etc. For each device we should add at least these sysfs entries: - system : This file return "1" if the generator takes the timing from the system clock, while it returns "0" if not (i.e. from a peripheral device clock). - time : This file contains the current time stored into the generator clock as two integers representing the current time seconds and nanoseconds. - enable : This write-only file enables or disables generation of the PPS signal. - period : This file defines the period for the generator signal. When read, by default, it returns "1 0" which represent the period second and nanoseconds (i.e. a PPS signal). When written, it sets the period accordingly or ENOTSUPP if not supported. - start_time : This file defines the starting time for the the generator signal. When read, by default, it returns "0 0" which means "now". When written, it sets the starting time accordingly or ENOTSUPP if not supported. Please, let me know what do you think about this proposal. I'm going to provide a draft in the next weeks since I'm stuck on another project right now. :( Ciao, Rodolfo -- GNU/Linux Solutions e-mail: giometti@enneenne.com Linux Device Driver giometti@linux.it Embedded Systems phone: +39 349 2432127 UNIX programming