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(ptr-eiyd6234yxkksfgejd7.18120a2.ip6.access.telenet.be. [2a02:1811:e422:ad00:f58d:9165:44ce:c58b]) by smtp.gmail.com with ESMTPSA id u188sm1461242wmg.37.2020.04.24.02.19.07 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 24 Apr 2020 02:19:08 -0700 (PDT) To: linux-wireless@vger.kernel.org From: Wei Liu Subject: Questions regarding 802.11 TM and FTM in cfg80211/mac80211 Message-ID: Date: Fri, 24 Apr 2020 11:19:09 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org Dear experts, I am new to Linux kernel, and I have an ambitious goal to run ptp over wireless (yes I know..  and please don't judge .. ) When I browse code in mac80211, I found function start_pmsr in ieee80211_ops. At this moment, this function is serving a request (defined in cfg80211) to start peer measurement, and the request seems rather FTM specific. Is there some code available to support the original Timing Measurement? As I am not interested in localization/ranging, but interested in synchronization, so the basic TM is enough for me. Regarding FTM, the current cfg80211_pmsr_ftm_result does not contain the ToD, ToA timestamps, it only reports the RTT. Is there a proper way to expose these timestamps to the user space? Thank you in advance for any guidance, Wei