From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 9B9FD2F692C; Wed, 28 Jan 2026 15:41:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769614870; cv=none; b=ZQ9kngb1ZnNLk/xtnn51AS1GCjIy0D6CZYu+Q9vtf9spjnEbHbLUFsfsVJGeV9WnaUdOqzhnuoyF2rEtRnInA7uMTClBhHfsQ6zlh20HoUemzRY53WvY3iJpikiYL24Fl/4c4lg8RReoZTR91JcFprIGGb+35QEk4+KEzqZglL8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769614870; c=relaxed/simple; bh=OUlvegC9xxurRvZJPEFDK3ZuTiYWQ762XN/fnEgjuh8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Umf7eDinCiEpsX2RpaEnyNr4ThlKP0Dp2jc9KR9Vf/4UbChiP1Jv7pd79S7ykVOa+iS6ck2nbfgHsYe0pWOPJRLQoC0nNZCC/pA8rN1ki6ELevbT5Qq32oiAccZ5WvwdscvYxoSnVix4jSAfAgwNCwmhm4xFSS5Wg0Q1CFSBY+M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=VpJ8CSLT; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="VpJ8CSLT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AE364C4CEF1; Wed, 28 Jan 2026 15:41:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1769614870; bh=OUlvegC9xxurRvZJPEFDK3ZuTiYWQ762XN/fnEgjuh8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VpJ8CSLTsysqHvGy0NsN9RbpLTOUKEPvb9PkqY0tj9+TUuXWOIRjYSnStpxzXGz5R dk0X+T6XXZWFVLysBzN59Q/pMcL7dz/rrZ2jaaDdNt0VdQlQpz6Y61IpGn2Oazchc+ uL3ntihharrbG5aGF2v0HyXq878LqVzxTb6Ncx0U= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Richard Cochran , Vadim Fedorenko , Wojtek Wasko , "David S. Miller" , Sasha Levin Subject: [PATCH 6.12 004/169] testptp: Add option to open PHC in readonly mode Date: Wed, 28 Jan 2026 16:21:27 +0100 Message-ID: <20260128145334.171288227@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260128145334.006287341@linuxfoundation.org> References: <20260128145334.006287341@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Wojtek Wasko [ Upstream commit 76868642e42795353106197abf9c607ad80f4c9e ] PTP Hardware Clocks no longer require WRITE permission to perform readonly operations, such as listing device capabilities or listening to EXTTS events once they have been enabled by a process with WRITE permissions. Add '-r' option to testptp to open the PHC in readonly mode instead of the default read-write mode. Skip enabling EXTTS if readonly mode is requested. Acked-by: Richard Cochran Reviewed-by: Vadim Fedorenko Signed-off-by: Wojtek Wasko Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- tools/testing/selftests/ptp/testptp.c | 37 +++++++++++++++++---------- 1 file changed, 23 insertions(+), 14 deletions(-) diff --git a/tools/testing/selftests/ptp/testptp.c b/tools/testing/selftests/ptp/testptp.c index 58064151f2c89..edc08a4433fd4 100644 --- a/tools/testing/selftests/ptp/testptp.c +++ b/tools/testing/selftests/ptp/testptp.c @@ -140,6 +140,7 @@ static void usage(char *progname) " -H val set output phase to 'val' nanoseconds (requires -p)\n" " -w val set output pulse width to 'val' nanoseconds (requires -p)\n" " -P val enable or disable (val=1|0) the system clock PPS\n" + " -r open the ptp clock in readonly mode\n" " -s set the ptp clock time from the system time\n" " -S set the system time from the ptp clock time\n" " -t val shift the ptp clock time by 'val' seconds\n" @@ -188,6 +189,7 @@ int main(int argc, char *argv[]) int pin_index = -1, pin_func; int pps = -1; int seconds = 0; + int readonly = 0; int settime = 0; int channel = -1; clockid_t ext_clockid = CLOCK_REALTIME; @@ -200,7 +202,7 @@ int main(int argc, char *argv[]) progname = strrchr(argv[0], '/'); progname = progname ? 1+progname : argv[0]; - while (EOF != (c = getopt(argc, argv, "cd:e:f:F:ghH:i:k:lL:n:o:p:P:sSt:T:w:x:Xy:z"))) { + while (EOF != (c = getopt(argc, argv, "cd:e:f:F:ghH:i:k:lL:n:o:p:P:rsSt:T:w:x:Xy:z"))) { switch (c) { case 'c': capabilities = 1; @@ -252,6 +254,9 @@ int main(int argc, char *argv[]) case 'P': pps = atoi(optarg); break; + case 'r': + readonly = 1; + break; case 's': settime = 1; break; @@ -308,7 +313,7 @@ int main(int argc, char *argv[]) } } - fd = open(device, O_RDWR); + fd = open(device, readonly ? O_RDONLY : O_RDWR); if (fd < 0) { fprintf(stderr, "opening %s: %s\n", device, strerror(errno)); return -1; @@ -436,14 +441,16 @@ int main(int argc, char *argv[]) } if (extts) { - memset(&extts_request, 0, sizeof(extts_request)); - extts_request.index = index; - extts_request.flags = PTP_ENABLE_FEATURE; - if (ioctl(fd, PTP_EXTTS_REQUEST, &extts_request)) { - perror("PTP_EXTTS_REQUEST"); - extts = 0; - } else { - puts("external time stamp request okay"); + if (!readonly) { + memset(&extts_request, 0, sizeof(extts_request)); + extts_request.index = index; + extts_request.flags = PTP_ENABLE_FEATURE; + if (ioctl(fd, PTP_EXTTS_REQUEST, &extts_request)) { + perror("PTP_EXTTS_REQUEST"); + extts = 0; + } else { + puts("external time stamp request okay"); + } } for (; extts; extts--) { cnt = read(fd, &event, sizeof(event)); @@ -455,10 +462,12 @@ int main(int argc, char *argv[]) event.t.sec, event.t.nsec); fflush(stdout); } - /* Disable the feature again. */ - extts_request.flags = 0; - if (ioctl(fd, PTP_EXTTS_REQUEST, &extts_request)) { - perror("PTP_EXTTS_REQUEST"); + if (!readonly) { + /* Disable the feature again. */ + extts_request.flags = 0; + if (ioctl(fd, PTP_EXTTS_REQUEST, &extts_request)) { + perror("PTP_EXTTS_REQUEST"); + } } } -- 2.51.0