[PATCH V15 1/4] ptp: Added a brand new class driver for ptp clocks.
Richard Cochran
richardcochran at gmail.com
Fri Apr 22 20:03:08 EST 2011
This patch adds an infrastructure for hardware clocks that implement
IEEE 1588, the Precision Time Protocol (PTP). A class driver offers a
registration method to particular hardware clock drivers. Each clock is
presented as a standard POSIX clock.
The ancillary clock features are exposed in two different ways, via
the sysfs and by a character device.
Signed-off-by: Richard Cochran <richard.cochran at omicron.at>
Acked-by: Arnd Bergmann <arnd at arndb.de>
Acked-by: David S. Miller <davem at davemloft.net>
---
Documentation/ABI/testing/sysfs-ptp | 98 +++++++++
Documentation/ptp/ptp.txt | 89 ++++++++
Documentation/ptp/testptp.c | 381 +++++++++++++++++++++++++++++++++++
Documentation/ptp/testptp.mk | 33 +++
drivers/Kconfig | 2 +
drivers/Makefile | 1 +
drivers/ptp/Kconfig | 30 +++
drivers/ptp/Makefile | 6 +
drivers/ptp/ptp_chardev.c | 159 +++++++++++++++
drivers/ptp/ptp_clock.c | 343 +++++++++++++++++++++++++++++++
drivers/ptp/ptp_private.h | 92 +++++++++
drivers/ptp/ptp_sysfs.c | 230 +++++++++++++++++++++
include/linux/Kbuild | 1 +
include/linux/ptp_classify.h | 7 +
include/linux/ptp_clock.h | 84 ++++++++
include/linux/ptp_clock_kernel.h | 139 +++++++++++++
16 files changed, 1695 insertions(+), 0 deletions(-)
create mode 100644 Documentation/ABI/testing/sysfs-ptp
create mode 100644 Documentation/ptp/ptp.txt
create mode 100644 Documentation/ptp/testptp.c
create mode 100644 Documentation/ptp/testptp.mk
create mode 100644 drivers/ptp/Kconfig
create mode 100644 drivers/ptp/Makefile
create mode 100644 drivers/ptp/ptp_chardev.c
create mode 100644 drivers/ptp/ptp_clock.c
create mode 100644 drivers/ptp/ptp_private.h
create mode 100644 drivers/ptp/ptp_sysfs.c
create mode 100644 include/linux/ptp_clock.h
create mode 100644 include/linux/ptp_clock_kernel.h
diff --git a/Documentation/ABI/testing/sysfs-ptp b/Documentation/ABI/testing/sysfs-ptp
new file mode 100644
index 0000000..d40d2b5
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-ptp
@@ -0,0 +1,98 @@
+What: /sys/class/ptp/
+Date: September 2010
+Contact: Richard Cochran <richardcochran at gmail.com>
+Description:
+ This directory contains files and directories
+ providing a standardized interface to the ancillary
+ features of PTP hardware clocks.
+
+What: /sys/class/ptp/ptpN/
+Date: September 2010
+Contact: Richard Cochran <richardcochran at gmail.com>
+Description:
+ This directory contains the attributes of the Nth PTP
+ hardware clock registered into the PTP class driver
+ subsystem.
+
+What: /sys/class/ptp/ptpN/clock_name
+Date: September 2010
+Contact: Richard Cochran <richardcochran at gmail.com>
+Description:
+ This file contains the name of the PTP hardware clock
+ as a human readable string.
+
+What: /sys/class/ptp/ptpN/max_adjustment
+Date: September 2010
+Contact: Richard Cochran <richardcochran at gmail.com>
+Description:
+ This file contains the PTP hardware clock's maximum
+ frequency adjustment value (a positive integer) in
+ parts per billion.
+
+What: /sys/class/ptp/ptpN/n_alarms
+Date: September 2010
+Contact: Richard Cochran <richardcochran at gmail.com>
+Description:
+ This file contains the number of periodic or one shot
+ alarms offer by the PTP hardware clock.
+
+What: /sys/class/ptp/ptpN/n_external_timestamps
+Date: September 2010
+Contact: Richard Cochran <richardcochran at gmail.com>
+Description:
+ This file contains the number of external timestamp
+ channels offered by the PTP hardware clock.
+
+What: /sys/class/ptp/ptpN/n_periodic_outputs
+Date: September 2010
+Contact: Richard Cochran <richardcochran at gmail.com>
+Description:
+ This file contains the number of programmable periodic
+ output channels offered by the PTP hardware clock.
+
+What: /sys/class/ptp/ptpN/pps_avaiable
+Date: September 2010
+Contact: Richard Cochran <richardcochran at gmail.com>
+Description:
+ This file indicates whether the PTP hardware clock
+ supports a Pulse Per Second to the host CPU. Reading
+ "1" means that the PPS is supported, while "0" means
+ not supported.
+
+What: /sys/class/ptp/ptpN/extts_enable
+Date: September 2010
+Contact: Richard Cochran <richardcochran at gmail.com>
+Description:
+ This write-only file enables or disables external
+ timestamps. To enable external timestamps, write the
+ channel index followed by a "1" into the file.
+ To disable external timestamps, write the channel
+ index followed by a "0" into the file.
+
+What: /sys/class/ptp/ptpN/fifo
+Date: September 2010
+Contact: Richard Cochran <richardcochran at gmail.com>
+Description:
+ This file provides timestamps on external events, in
+ the form of three integers: channel index, seconds,
+ and nanoseconds.
+
+What: /sys/class/ptp/ptpN/period
+Date: September 2010
+Contact: Richard Cochran <richardcochran at gmail.com>
+Description:
+ This write-only file enables or disables periodic
+ outputs. To enable a periodic output, write five
+ integers into the file: channel index, start time
+ seconds, start time nanoseconds, period seconds, and
+ period nanoseconds. To disable a periodic output, set
+ all the seconds and nanoseconds values to zero.
+
+What: /sys/class/ptp/ptpN/pps_enable
+Date: September 2010
+Contact: Richard Cochran <richardcochran at gmail.com>
+Description:
+ This write-only file enables or disables delivery of
+ PPS events to the Linux PPS subsystem. To enable PPS
+ events, write a "1" into the file. To disable events,
+ write a "0" into the file.
diff --git a/Documentation/ptp/ptp.txt b/Documentation/ptp/ptp.txt
new file mode 100644
index 0000000..ae8fef8
--- /dev/null
+++ b/Documentation/ptp/ptp.txt
@@ -0,0 +1,89 @@
+
+* PTP hardware clock infrastructure for Linux
+
+ This patch set introduces support for IEEE 1588 PTP clocks in
+ Linux. Together with the SO_TIMESTAMPING socket options, this
+ presents a standardized method for developing PTP user space
+ programs, synchronizing Linux with external clocks, and using the
+ ancillary features of PTP hardware clocks.
+
+ A new class driver exports a kernel interface for specific clock
+ drivers and a user space interface. The infrastructure supports a
+ complete set of PTP hardware clock functionality.
+
+ + Basic clock operations
+ - Set time
+ - Get time
+ - Shift the clock by a given offset atomically
+ - Adjust clock frequency
+
+ + Ancillary clock features
+ - One short or periodic alarms, with signal delivery to user program
+ - Time stamp external events
+ - Period output signals configurable from user space
+ - Synchronization of the Linux system time via the PPS subsystem
+
+** PTP hardware clock kernel API
+
+ A PTP clock driver registers itself with the class driver. The
+ class driver handles all of the dealings with user space. The
+ author of a clock driver need only implement the details of
+ programming the clock hardware. The clock driver notifies the class
+ driver of asynchronous events (alarms and external time stamps) via
+ a simple message passing interface.
+
+ The class driver supports multiple PTP clock drivers. In normal use
+ cases, only one PTP clock is needed. However, for testing and
+ development, it can be useful to have more than one clock in a
+ single system, in order to allow performance comparisons.
+
+** PTP hardware clock user space API
+
+ The class driver also creates a character device for each
+ registered clock. User space can use an open file descriptor from
+ the character device as a POSIX clock id and may call
+ clock_gettime, clock_settime, and clock_adjtime. These calls
+ implement the basic clock operations.
+
+ User space programs may control the clock using standardized
+ ioctls. A program may query, enable, configure, and disable the
+ ancillary clock features. User space can receive time stamped
+ events via blocking read() and poll(). One shot and periodic
+ signals may be configured via the POSIX timer_settime() system
+ call.
+
+** Writing clock drivers
+
+ Clock drivers include include/linux/ptp_clock_kernel.h and register
+ themselves by presenting a 'struct ptp_clock_info' to the
+ registration method. Clock drivers must implement all of the
+ functions in the interface. If a clock does not offer a particular
+ ancillary feature, then the driver should just return -EOPNOTSUPP
+ from those functions.
+
+ Drivers must ensure that all of the methods in interface are
+ reentrant. Since most hardware implementations treat the time value
+ as a 64 bit integer accessed as two 32 bit registers, drivers
+ should use spin_lock_irqsave/spin_unlock_irqrestore to protect
+ against concurrent access. This locking cannot be accomplished in
+ class driver, since the lock may also be needed by the clock
+ driver's interrupt service routine.
+
+** Supported hardware
+
+ + Freescale eTSEC gianfar
+ - 2 Time stamp external triggers, programmable polarity (opt. interrupt)
+ - 2 Alarm registers (optional interrupt)
+ - 3 Periodic signals (optional interrupt)
+
+ + National DP83640
+ - 6 GPIOs programmable as inputs or outputs
+ - 6 GPIOs with dedicated functions (LED/JTAG/clock) can also be
+ used as general inputs or outputs
+ - GPIO inputs can time stamp external triggers
+ - GPIO outputs can produce periodic signals
+ - 1 interrupt pin
+
+ + Intel IXP465
+ - Auxiliary Slave/Master Mode Snapshot (optional interrupt)
+ - Target Time (optional interrupt)
diff --git a/Documentation/ptp/testptp.c b/Documentation/ptp/testptp.c
new file mode 100644
index 0000000..f59ded0
--- /dev/null
+++ b/Documentation/ptp/testptp.c
@@ -0,0 +1,381 @@
+/*
+ * PTP 1588 clock support - User space test program
+ *
+ * Copyright (C) 2010 OMICRON electronics GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <errno.h>
+#include <fcntl.h>
+#include <math.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/timex.h>
+#include <sys/types.h>
+#include <time.h>
+#include <unistd.h>
+
+#include <linux/ptp_clock.h>
+
+#define DEVICE "/dev/ptp0"
+
+#ifndef ADJ_SETOFFSET
+#define ADJ_SETOFFSET 0x0100
+#endif
+
+#ifndef CLOCK_INVALID
+#define CLOCK_INVALID -1
+#endif
+
+/* When glibc offers the syscall, this will go away. */
+#include <sys/syscall.h>
+static int clock_adjtime(clockid_t id, struct timex *tx)
+{
+ return syscall(__NR_clock_adjtime, id, tx);
+}
+
+static clockid_t get_clockid(int fd)
+{
+#define CLOCKFD 3
+#define FD_TO_CLOCKID(fd) ((~(clockid_t) (fd) << 3) | CLOCKFD)
+
+ return FD_TO_CLOCKID(fd);
+}
+
+static void handle_alarm(int s)
+{
+ printf("received signal %d\n", s);
+}
+
+static int install_handler(int signum, void (*handler)(int))
+{
+ struct sigaction action;
+ sigset_t mask;
+
+ /* Unblock the signal. */
+ sigemptyset(&mask);
+ sigaddset(&mask, signum);
+ sigprocmask(SIG_UNBLOCK, &mask, NULL);
+
+ /* Install the signal handler. */
+ action.sa_handler = handler;
+ action.sa_flags = 0;
+ sigemptyset(&action.sa_mask);
+ sigaction(signum, &action, NULL);
+
+ return 0;
+}
+
+static long ppb_to_scaled_ppm(int ppb)
+{
+ /*
+ * The 'freq' field in the 'struct timex' is in parts per
+ * million, but with a 16 bit binary fractional field.
+ * Instead of calculating either one of
+ *
+ * scaled_ppm = (ppb / 1000) << 16 [1]
+ * scaled_ppm = (ppb << 16) / 1000 [2]
+ *
+ * we simply use double precision math, in order to avoid the
+ * truncation in [1] and the possible overflow in [2].
+ */
+ return (long) (ppb * 65.536);
+}
+
+static void usage(char *progname)
+{
+ fprintf(stderr,
+ "usage: %s [options]\n"
+ " -a val request a one-shot alarm after 'val' seconds\n"
+ " -A val request a periodic alarm every 'val' seconds\n"
+ " -c query the ptp clock's capabilities\n"
+ " -d name device to open\n"
+ " -e val read 'val' external time stamp events\n"
+ " -f val adjust the ptp clock frequency by 'val' ppb\n"
+ " -g get the ptp clock time\n"
+ " -h prints this message\n"
+ " -p val enable output with a period of 'val' nanoseconds\n"
+ " -P val enable or disable (val=1|0) the system clock PPS\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",
+ progname);
+}
+
+int main(int argc, char *argv[])
+{
+ struct ptp_clock_caps caps;
+ struct ptp_extts_event event;
+ struct ptp_extts_request extts_request;
+ struct ptp_perout_request perout_request;
+ struct timespec ts;
+ struct timex tx;
+
+ static timer_t timerid;
+ struct itimerspec timeout;
+ struct sigevent sigevent;
+
+ char *progname;
+ int c, cnt, fd;
+
+ char *device = DEVICE;
+ clockid_t clkid;
+ int adjfreq = 0x7fffffff;
+ int adjtime = 0;
+ int capabilities = 0;
+ int extts = 0;
+ int gettime = 0;
+ int oneshot = 0;
+ int periodic = 0;
+ int perout = -1;
+ int pps = -1;
+ int settime = 0;
+
+ progname = strrchr(argv[0], '/');
+ progname = progname ? 1+progname : argv[0];
+ while (EOF != (c = getopt(argc, argv, "a:A:cd:e:f:ghp:P:sSt:v"))) {
+ switch (c) {
+ case 'a':
+ oneshot = atoi(optarg);
+ break;
+ case 'A':
+ periodic = atoi(optarg);
+ break;
+ case 'c':
+ capabilities = 1;
+ break;
+ case 'd':
+ device = optarg;
+ break;
+ case 'e':
+ extts = atoi(optarg);
+ break;
+ case 'f':
+ adjfreq = atoi(optarg);
+ break;
+ case 'g':
+ gettime = 1;
+ break;
+ case 'p':
+ perout = atoi(optarg);
+ break;
+ case 'P':
+ pps = atoi(optarg);
+ break;
+ case 's':
+ settime = 1;
+ break;
+ case 'S':
+ settime = 2;
+ break;
+ case 't':
+ adjtime = atoi(optarg);
+ break;
+ case 'h':
+ usage(progname);
+ return 0;
+ case '?':
+ default:
+ usage(progname);
+ return -1;
+ }
+ }
+
+ fd = open(device, O_RDWR);
+ if (fd < 0) {
+ fprintf(stderr, "opening %s: %s\n", device, strerror(errno));
+ return -1;
+ }
+
+ clkid = get_clockid(fd);
+ if (CLOCK_INVALID == clkid) {
+ fprintf(stderr, "failed to read clock id\n");
+ return -1;
+ }
+
+ if (capabilities) {
+ if (ioctl(fd, PTP_CLOCK_GETCAPS, &caps)) {
+ perror("PTP_CLOCK_GETCAPS");
+ } else {
+ printf("capabilities:\n"
+ " %d maximum frequency adjustment (ppb)\n"
+ " %d programmable alarms\n"
+ " %d external time stamp channels\n"
+ " %d programmable periodic signals\n"
+ " %d pulse per second\n",
+ caps.max_adj,
+ caps.n_alarm,
+ caps.n_ext_ts,
+ caps.n_per_out,
+ caps.pps);
+ }
+ }
+
+ if (0x7fffffff != adjfreq) {
+ memset(&tx, 0, sizeof(tx));
+ tx.modes = ADJ_FREQUENCY;
+ tx.freq = ppb_to_scaled_ppm(adjfreq);
+ if (clock_adjtime(clkid, &tx)) {
+ perror("clock_adjtime");
+ } else {
+ puts("frequency adjustment okay");
+ }
+ }
+
+ if (adjtime) {
+ memset(&tx, 0, sizeof(tx));
+ tx.modes = ADJ_SETOFFSET;
+ tx.time.tv_sec = adjtime;
+ tx.time.tv_usec = 0;
+ if (clock_adjtime(clkid, &tx) < 0) {
+ perror("clock_adjtime");
+ } else {
+ puts("time shift okay");
+ }
+ }
+
+ if (gettime) {
+ if (clock_gettime(clkid, &ts)) {
+ perror("clock_gettime");
+ } else {
+ printf("clock time: %ld.%09ld or %s",
+ ts.tv_sec, ts.tv_nsec, ctime(&ts.tv_sec));
+ }
+ }
+
+ if (settime == 1) {
+ clock_gettime(CLOCK_REALTIME, &ts);
+ if (clock_settime(clkid, &ts)) {
+ perror("clock_settime");
+ } else {
+ puts("set time okay");
+ }
+ }
+
+ if (settime == 2) {
+ clock_gettime(clkid, &ts);
+ if (clock_settime(CLOCK_REALTIME, &ts)) {
+ perror("clock_settime");
+ } else {
+ puts("set time okay");
+ }
+ }
+
+ if (extts) {
+ memset(&extts_request, 0, sizeof(extts_request));
+ extts_request.index = 0;
+ 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));
+ if (cnt != sizeof(event)) {
+ perror("read");
+ break;
+ }
+ printf("event index %u at %lld.%09u\n", event.index,
+ 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 (oneshot) {
+ install_handler(SIGALRM, handle_alarm);
+ /* Create a timer. */
+ sigevent.sigev_notify = SIGEV_SIGNAL;
+ sigevent.sigev_signo = SIGALRM;
+ if (timer_create(clkid, &sigevent, &timerid)) {
+ perror("timer_create");
+ return -1;
+ }
+ /* Start the timer. */
+ memset(&timeout, 0, sizeof(timeout));
+ timeout.it_value.tv_sec = oneshot;
+ if (timer_settime(timerid, 0, &timeout, NULL)) {
+ perror("timer_settime");
+ return -1;
+ }
+ pause();
+ timer_delete(timerid);
+ }
+
+ if (periodic) {
+ install_handler(SIGALRM, handle_alarm);
+ /* Create a timer. */
+ sigevent.sigev_notify = SIGEV_SIGNAL;
+ sigevent.sigev_signo = SIGALRM;
+ if (timer_create(clkid, &sigevent, &timerid)) {
+ perror("timer_create");
+ return -1;
+ }
+ /* Start the timer. */
+ memset(&timeout, 0, sizeof(timeout));
+ timeout.it_interval.tv_sec = periodic;
+ timeout.it_value.tv_sec = periodic;
+ if (timer_settime(timerid, 0, &timeout, NULL)) {
+ perror("timer_settime");
+ return -1;
+ }
+ while (1) {
+ pause();
+ }
+ timer_delete(timerid);
+ }
+
+ if (perout >= 0) {
+ if (clock_gettime(clkid, &ts)) {
+ perror("clock_gettime");
+ return -1;
+ }
+ memset(&perout_request, 0, sizeof(perout_request));
+ perout_request.index = 0;
+ perout_request.start.sec = ts.tv_sec + 2;
+ perout_request.start.nsec = 0;
+ perout_request.period.sec = 0;
+ perout_request.period.nsec = perout;
+ if (ioctl(fd, PTP_PEROUT_REQUEST, &perout_request)) {
+ perror("PTP_PEROUT_REQUEST");
+ } else {
+ puts("periodic output request okay");
+ }
+ }
+
+ if (pps != -1) {
+ int enable = pps ? 1 : 0;
+ if (ioctl(fd, PTP_ENABLE_PPS, enable)) {
+ perror("PTP_ENABLE_PPS");
+ } else {
+ puts("pps for system time request okay");
+ }
+ }
+
+ close(fd);
+ return 0;
+}
diff --git a/Documentation/ptp/testptp.mk b/Documentation/ptp/testptp.mk
new file mode 100644
index 0000000..4ef2d97
--- /dev/null
+++ b/Documentation/ptp/testptp.mk
@@ -0,0 +1,33 @@
+# PTP 1588 clock support - User space test program
+#
+# Copyright (C) 2010 OMICRON electronics GmbH
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+CC = $(CROSS_COMPILE)gcc
+INC = -I$(KBUILD_OUTPUT)/usr/include
+CFLAGS = -Wall $(INC)
+LDLIBS = -lrt
+PROGS = testptp
+
+all: $(PROGS)
+
+testptp: testptp.o
+
+clean:
+ rm -f testptp.o
+
+distclean: clean
+ rm -f $(PROGS)
diff --git a/drivers/Kconfig b/drivers/Kconfig
index 177c7d1..6fd7446 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -54,6 +54,8 @@ source "drivers/spi/Kconfig"
source "drivers/pps/Kconfig"
+source "drivers/ptp/Kconfig"
+
source "drivers/gpio/Kconfig"
source "drivers/w1/Kconfig"
diff --git a/drivers/Makefile b/drivers/Makefile
index 3f135b6..71ebbf9 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -76,6 +76,7 @@ obj-$(CONFIG_I2O) += message/
obj-$(CONFIG_RTC_LIB) += rtc/
obj-y += i2c/ media/
obj-$(CONFIG_PPS) += pps/
+obj-$(CONFIG_PTP_1588_CLOCK) += ptp/
obj-$(CONFIG_W1) += w1/
obj-$(CONFIG_POWER_SUPPLY) += power/
obj-$(CONFIG_HWMON) += hwmon/
diff --git a/drivers/ptp/Kconfig b/drivers/ptp/Kconfig
new file mode 100644
index 0000000..70d4bb1
--- /dev/null
+++ b/drivers/ptp/Kconfig
@@ -0,0 +1,30 @@
+#
+# PTP clock support configuration
+#
+
+menu "PTP clock support"
+
+comment "Enable Device Drivers -> PPS to see the PTP clock options."
+ depends on PPS=n
+
+config PTP_1588_CLOCK
+ tristate "PTP clock support"
+ depends on EXPERIMENTAL
+ depends on PPS
+ help
+ The IEEE 1588 standard defines a method to precisely
+ synchronize distributed clocks over Ethernet networks. The
+ standard defines a Precision Time Protocol (PTP), which can
+ be used to achieve synchronization within a few dozen
+ microseconds. In addition, with the help of special hardware
+ time stamping units, it can be possible to achieve
+ synchronization to within a few hundred nanoseconds.
+
+ This driver adds support for PTP clocks as character
+ devices. If you want to use a PTP clock, then you should
+ also enable at least one clock driver as well.
+
+ To compile this driver as a module, choose M here: the module
+ will be called ptp.
+
+endmenu
diff --git a/drivers/ptp/Makefile b/drivers/ptp/Makefile
new file mode 100644
index 0000000..480e2af
--- /dev/null
+++ b/drivers/ptp/Makefile
@@ -0,0 +1,6 @@
+#
+# Makefile for PTP 1588 clock support.
+#
+
+ptp-y := ptp_clock.o ptp_chardev.o ptp_sysfs.o
+obj-$(CONFIG_PTP_1588_CLOCK) += ptp.o
diff --git a/drivers/ptp/ptp_chardev.c b/drivers/ptp/ptp_chardev.c
new file mode 100644
index 0000000..a8d03ae
--- /dev/null
+++ b/drivers/ptp/ptp_chardev.c
@@ -0,0 +1,159 @@
+/*
+ * PTP 1588 clock support - character device implementation.
+ *
+ * Copyright (C) 2010 OMICRON electronics GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <linux/module.h>
+#include <linux/posix-clock.h>
+#include <linux/poll.h>
+#include <linux/sched.h>
+
+#include "ptp_private.h"
+
+int ptp_open(struct posix_clock *pc, fmode_t fmode)
+{
+ return 0;
+}
+
+long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
+{
+ struct ptp_clock_caps caps;
+ struct ptp_clock_request req;
+ struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
+ struct ptp_clock_info *ops = ptp->info;
+ int enable, err = 0;
+
+ switch (cmd) {
+
+ case PTP_CLOCK_GETCAPS:
+ memset(&caps, 0, sizeof(caps));
+ caps.max_adj = ptp->info->max_adj;
+ caps.n_alarm = ptp->info->n_alarm;
+ caps.n_ext_ts = ptp->info->n_ext_ts;
+ caps.n_per_out = ptp->info->n_per_out;
+ caps.pps = ptp->info->pps;
+ err = copy_to_user((void __user *)arg, &caps, sizeof(caps));
+ break;
+
+ case PTP_EXTTS_REQUEST:
+ if (copy_from_user(&req.extts, (void __user *)arg,
+ sizeof(req.extts))) {
+ err = -EFAULT;
+ break;
+ }
+ if (req.extts.index >= ops->n_ext_ts) {
+ err = -EINVAL;
+ break;
+ }
+ req.type = PTP_CLK_REQ_EXTTS;
+ enable = req.extts.flags & PTP_ENABLE_FEATURE ? 1 : 0;
+ err = ops->enable(ops, &req, enable);
+ break;
+
+ case PTP_PEROUT_REQUEST:
+ if (copy_from_user(&req.perout, (void __user *)arg,
+ sizeof(req.perout))) {
+ err = -EFAULT;
+ break;
+ }
+ if (req.perout.index >= ops->n_per_out) {
+ err = -EINVAL;
+ break;
+ }
+ req.type = PTP_CLK_REQ_PEROUT;
+ enable = req.perout.period.sec || req.perout.period.nsec;
+ err = ops->enable(ops, &req, enable);
+ break;
+
+ case PTP_ENABLE_PPS:
+ if (!capable(CAP_SYS_TIME))
+ return -EPERM;
+ req.type = PTP_CLK_REQ_PPS;
+ enable = arg ? 1 : 0;
+ err = ops->enable(ops, &req, enable);
+ break;
+
+ default:
+ err = -ENOTTY;
+ break;
+ }
+ return err;
+}
+
+unsigned int ptp_poll(struct posix_clock *pc, struct file *fp, poll_table *wait)
+{
+ struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
+
+ poll_wait(fp, &ptp->tsev_wq, wait);
+
+ return queue_cnt(&ptp->tsevq) ? POLLIN : 0;
+}
+
+ssize_t ptp_read(struct posix_clock *pc,
+ uint rdflags, char __user *buf, size_t cnt)
+{
+ struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
+ struct timestamp_event_queue *queue = &ptp->tsevq;
+ struct ptp_extts_event event[PTP_BUF_TIMESTAMPS];
+ unsigned long flags;
+ size_t qcnt, i;
+
+ if (cnt % sizeof(struct ptp_extts_event) != 0)
+ return -EINVAL;
+
+ if (cnt > sizeof(event))
+ cnt = sizeof(event);
+
+ cnt = cnt / sizeof(struct ptp_extts_event);
+
+ if (mutex_lock_interruptible(&ptp->tsevq_mux))
+ return -ERESTARTSYS;
+
+ if (wait_event_interruptible(ptp->tsev_wq,
+ ptp->defunct || queue_cnt(queue))) {
+ mutex_unlock(&ptp->tsevq_mux);
+ return -ERESTARTSYS;
+ }
+
+ if (ptp->defunct)
+ return -ENODEV;
+
+ spin_lock_irqsave(&queue->lock, flags);
+
+ qcnt = queue_cnt(queue);
+
+ if (cnt > qcnt)
+ cnt = qcnt;
+
+ for (i = 0; i < cnt; i++) {
+ event[i] = queue->buf[queue->head];
+ queue->head = (queue->head + 1) % PTP_MAX_TIMESTAMPS;
+ }
+
+ spin_unlock_irqrestore(&queue->lock, flags);
+
+ cnt = cnt * sizeof(struct ptp_extts_event);
+
+ mutex_unlock(&ptp->tsevq_mux);
+
+ if (copy_to_user(buf, event, cnt)) {
+ mutex_unlock(&ptp->tsevq_mux);
+ return -EFAULT;
+ }
+
+ return cnt;
+}
diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c
new file mode 100644
index 0000000..cf3f999
--- /dev/null
+++ b/drivers/ptp/ptp_clock.c
@@ -0,0 +1,343 @@
+/*
+ * PTP 1588 clock support
+ *
+ * Copyright (C) 2010 OMICRON electronics GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/posix-clock.h>
+#include <linux/pps_kernel.h>
+#include <linux/slab.h>
+#include <linux/syscalls.h>
+#include <linux/uaccess.h>
+
+#include "ptp_private.h"
+
+#define PTP_MAX_ALARMS 4
+#define PTP_MAX_CLOCKS 8
+#define PTP_PPS_DEFAULTS (PPS_CAPTUREASSERT | PPS_OFFSETASSERT)
+#define PTP_PPS_EVENT PPS_CAPTUREASSERT
+#define PTP_PPS_MODE (PTP_PPS_DEFAULTS | PPS_CANWAIT | PPS_TSFMT_TSPEC)
+
+/* private globals */
+
+static dev_t ptp_devt;
+static struct class *ptp_class;
+
+static DECLARE_BITMAP(ptp_clocks_map, PTP_MAX_CLOCKS);
+static DEFINE_MUTEX(ptp_clocks_mutex); /* protects 'ptp_clocks_map' */
+
+/* time stamp event queue operations */
+
+static inline int queue_free(struct timestamp_event_queue *q)
+{
+ return PTP_MAX_TIMESTAMPS - queue_cnt(q) - 1;
+}
+
+static void enqueue_external_timestamp(struct timestamp_event_queue *queue,
+ struct ptp_clock_event *src)
+{
+ struct ptp_extts_event *dst;
+ unsigned long flags;
+ s64 seconds;
+ u32 remainder;
+
+ seconds = div_u64_rem(src->timestamp, 1000000000, &remainder);
+
+ spin_lock_irqsave(&queue->lock, flags);
+
+ dst = &queue->buf[queue->tail];
+ dst->index = src->index;
+ dst->t.sec = seconds;
+ dst->t.nsec = remainder;
+
+ if (!queue_free(queue))
+ queue->head = (queue->head + 1) % PTP_MAX_TIMESTAMPS;
+
+ queue->tail = (queue->tail + 1) % PTP_MAX_TIMESTAMPS;
+
+ spin_unlock_irqrestore(&queue->lock, flags);
+}
+
+static s32 scaled_ppm_to_ppb(long ppm)
+{
+ /*
+ * The 'freq' field in the 'struct timex' is in parts per
+ * million, but with a 16 bit binary fractional field.
+ *
+ * We want to calculate
+ *
+ * ppb = scaled_ppm * 1000 / 2^16
+ *
+ * which simplifies to
+ *
+ * ppb = scaled_ppm * 125 / 2^13
+ */
+ s64 ppb = 1 + ppm;
+ ppb *= 125;
+ ppb >>= 13;
+ return (s32) ppb;
+}
+
+/* posix clock implementation */
+
+static int ptp_clock_getres(struct posix_clock *pc, struct timespec *tp)
+{
+ return 1; /* always round timer functions to one nanosecond */
+}
+
+static int ptp_clock_settime(struct posix_clock *pc, const struct timespec *tp)
+{
+ struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
+ return ptp->info->settime(ptp->info, tp);
+}
+
+static int ptp_clock_gettime(struct posix_clock *pc, struct timespec *tp)
+{
+ struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
+ return ptp->info->gettime(ptp->info, tp);
+}
+
+static int ptp_clock_adjtime(struct posix_clock *pc, struct timex *tx)
+{
+ struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
+ struct ptp_clock_info *ops;
+ int err = -EOPNOTSUPP;
+
+ ops = ptp->info;
+
+ if (tx->modes & ADJ_SETOFFSET) {
+ struct timespec ts;
+ ktime_t kt;
+ s64 delta;
+
+ ts.tv_sec = tx->time.tv_sec;
+ ts.tv_nsec = tx->time.tv_usec;
+
+ if (!(tx->modes & ADJ_NANO))
+ ts.tv_nsec *= 1000;
+
+ if ((unsigned long) ts.tv_nsec >= NSEC_PER_SEC)
+ return -EINVAL;
+
+ kt = timespec_to_ktime(ts);
+ delta = ktime_to_ns(kt);
+ err = ops->adjtime(ops, delta);
+
+ } else if (tx->modes & ADJ_FREQUENCY) {
+
+ err = ops->adjfreq(ops, scaled_ppm_to_ppb(tx->freq));
+ }
+
+ return err;
+}
+
+static struct posix_clock_operations ptp_clock_ops = {
+ .owner = THIS_MODULE,
+ .clock_adjtime = ptp_clock_adjtime,
+ .clock_gettime = ptp_clock_gettime,
+ .clock_getres = ptp_clock_getres,
+ .clock_settime = ptp_clock_settime,
+ .ioctl = ptp_ioctl,
+ .open = ptp_open,
+ .poll = ptp_poll,
+ .read = ptp_read,
+};
+
+static void delete_ptp_clock(struct posix_clock *pc)
+{
+ struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
+
+ mutex_destroy(&ptp->tsevq_mux);
+
+ /* Remove the clock from the bit map. */
+ mutex_lock(&ptp_clocks_mutex);
+ clear_bit(ptp->index, ptp_clocks_map);
+ mutex_unlock(&ptp_clocks_mutex);
+
+ kfree(ptp);
+}
+
+/* public interface */
+
+struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info)
+{
+ struct ptp_clock *ptp;
+ int err = 0, index, major = MAJOR(ptp_devt);
+
+ if (info->n_alarm > PTP_MAX_ALARMS)
+ return ERR_PTR(-EINVAL);
+
+ /* Find a free clock slot and reserve it. */
+ err = -EBUSY;
+ mutex_lock(&ptp_clocks_mutex);
+ index = find_first_zero_bit(ptp_clocks_map, PTP_MAX_CLOCKS);
+ if (index < PTP_MAX_CLOCKS)
+ set_bit(index, ptp_clocks_map);
+ else
+ goto no_slot;
+
+ /* Initialize a clock structure. */
+ err = -ENOMEM;
+ ptp = kzalloc(sizeof(struct ptp_clock), GFP_KERNEL);
+ if (ptp == NULL)
+ goto no_memory;
+
+ ptp->clock.ops = ptp_clock_ops;
+ ptp->clock.release = delete_ptp_clock;
+ ptp->info = info;
+ ptp->devid = MKDEV(major, index);
+ ptp->index = index;
+ spin_lock_init(&ptp->tsevq.lock);
+ mutex_init(&ptp->tsevq_mux);
+ init_waitqueue_head(&ptp->tsev_wq);
+
+ /* Create a new device in our class. */
+ ptp->dev = device_create(ptp_class, NULL, ptp->devid, ptp,
+ "ptp%d", ptp->index);
+ if (IS_ERR(ptp->dev))
+ goto no_device;
+
+ dev_set_drvdata(ptp->dev, ptp);
+
+ err = ptp_populate_sysfs(ptp);
+ if (err)
+ goto no_sysfs;
+
+ /* Register a new PPS source. */
+ if (info->pps) {
+ struct pps_source_info pps;
+ memset(&pps, 0, sizeof(pps));
+ snprintf(pps.name, PPS_MAX_NAME_LEN, "ptp%d", index);
+ pps.mode = PTP_PPS_MODE;
+ pps.owner = info->owner;
+ ptp->pps_source = pps_register_source(&pps, PTP_PPS_DEFAULTS);
+ if (!ptp->pps_source) {
+ pr_err("failed to register pps source\n");
+ goto no_pps;
+ }
+ }
+
+ /* Create a posix clock. */
+ err = posix_clock_register(&ptp->clock, ptp->devid);
+ if (err) {
+ pr_err("failed to create posix clock\n");
+ goto no_clock;
+ }
+
+ mutex_unlock(&ptp_clocks_mutex);
+ return ptp;
+
+no_clock:
+ if (ptp->pps_source)
+ pps_unregister_source(ptp->pps_source);
+no_pps:
+ ptp_cleanup_sysfs(ptp);
+no_sysfs:
+ device_destroy(ptp_class, ptp->devid);
+no_device:
+ mutex_destroy(&ptp->tsevq_mux);
+ kfree(ptp);
+no_memory:
+ clear_bit(index, ptp_clocks_map);
+no_slot:
+ mutex_unlock(&ptp_clocks_mutex);
+ return ERR_PTR(err);
+}
+EXPORT_SYMBOL(ptp_clock_register);
+
+int ptp_clock_unregister(struct ptp_clock *ptp)
+{
+ ptp->defunct = 1;
+ wake_up_interruptible(&ptp->tsev_wq);
+
+ /* Release the clock's resources. */
+ if (ptp->pps_source)
+ pps_unregister_source(ptp->pps_source);
+ ptp_cleanup_sysfs(ptp);
+ device_destroy(ptp_class, ptp->devid);
+
+ posix_clock_unregister(&ptp->clock);
+ return 0;
+}
+EXPORT_SYMBOL(ptp_clock_unregister);
+
+void ptp_clock_event(struct ptp_clock *ptp, struct ptp_clock_event *event)
+{
+ struct pps_event_time evt;
+
+ switch (event->type) {
+
+ case PTP_CLOCK_ALARM:
+ break;
+
+ case PTP_CLOCK_EXTTS:
+ enqueue_external_timestamp(&ptp->tsevq, event);
+ wake_up_interruptible(&ptp->tsev_wq);
+ break;
+
+ case PTP_CLOCK_PPS:
+ pps_get_ts(&evt);
+ pps_event(ptp->pps_source, &evt, PTP_PPS_EVENT, NULL);
+ break;
+ }
+}
+EXPORT_SYMBOL(ptp_clock_event);
+
+/* module operations */
+
+static void __exit ptp_exit(void)
+{
+ class_destroy(ptp_class);
+ unregister_chrdev_region(ptp_devt, PTP_MAX_CLOCKS);
+}
+
+static int __init ptp_init(void)
+{
+ int err;
+
+ ptp_class = class_create(THIS_MODULE, "ptp");
+ if (IS_ERR(ptp_class)) {
+ pr_err("ptp: failed to allocate class\n");
+ return PTR_ERR(ptp_class);
+ }
+
+ err = alloc_chrdev_region(&ptp_devt, 0, PTP_MAX_CLOCKS, "ptp");
+ if (err < 0) {
+ pr_err("ptp: failed to allocate device region\n");
+ goto no_region;
+ }
+
+ ptp_class->dev_attrs = ptp_dev_attrs;
+ pr_info("PTP clock support registered\n");
+ return 0;
+
+no_region:
+ class_destroy(ptp_class);
+ return err;
+}
+
+subsys_initcall(ptp_init);
+module_exit(ptp_exit);
+
+MODULE_AUTHOR("Richard Cochran <richard.cochran at omicron.at>");
+MODULE_DESCRIPTION("PTP clocks support");
+MODULE_LICENSE("GPL");
diff --git a/drivers/ptp/ptp_private.h b/drivers/ptp/ptp_private.h
new file mode 100644
index 0000000..4d5b508
--- /dev/null
+++ b/drivers/ptp/ptp_private.h
@@ -0,0 +1,92 @@
+/*
+ * PTP 1588 clock support - private declarations for the core module.
+ *
+ * Copyright (C) 2010 OMICRON electronics GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#ifndef _PTP_PRIVATE_H_
+#define _PTP_PRIVATE_H_
+
+#include <linux/cdev.h>
+#include <linux/device.h>
+#include <linux/mutex.h>
+#include <linux/posix-clock.h>
+#include <linux/ptp_clock.h>
+#include <linux/ptp_clock_kernel.h>
+#include <linux/time.h>
+
+#define PTP_MAX_TIMESTAMPS 128
+#define PTP_BUF_TIMESTAMPS 30
+
+struct timestamp_event_queue {
+ struct ptp_extts_event buf[PTP_MAX_TIMESTAMPS];
+ int head;
+ int tail;
+ spinlock_t lock;
+};
+
+struct ptp_clock {
+ struct posix_clock clock;
+ struct device *dev;
+ struct ptp_clock_info *info;
+ dev_t devid;
+ int index; /* index into clocks.map */
+ struct pps_device *pps_source;
+ struct timestamp_event_queue tsevq; /* simple fifo for time stamps */
+ struct mutex tsevq_mux; /* one process at a time reading the fifo */
+ wait_queue_head_t tsev_wq;
+ int defunct; /* tells readers to go away when clock is being removed */
+};
+
+/*
+ * The function queue_cnt() is safe for readers to call without
+ * holding q->lock. Readers use this function to verify that the queue
+ * is nonempty before proceeding with a dequeue operation. The fact
+ * that a writer might concurrently increment the tail does not
+ * matter, since the queue remains nonempty nonetheless.
+ */
+static inline int queue_cnt(struct timestamp_event_queue *q)
+{
+ int cnt = q->tail - q->head;
+ return cnt < 0 ? PTP_MAX_TIMESTAMPS + cnt : cnt;
+}
+
+/*
+ * see ptp_chardev.c
+ */
+
+long ptp_ioctl(struct posix_clock *pc,
+ unsigned int cmd, unsigned long arg);
+
+int ptp_open(struct posix_clock *pc, fmode_t fmode);
+
+ssize_t ptp_read(struct posix_clock *pc,
+ uint flags, char __user *buf, size_t cnt);
+
+uint ptp_poll(struct posix_clock *pc,
+ struct file *fp, poll_table *wait);
+
+/*
+ * see ptp_sysfs.c
+ */
+
+extern struct device_attribute ptp_dev_attrs[];
+
+int ptp_cleanup_sysfs(struct ptp_clock *ptp);
+
+int ptp_populate_sysfs(struct ptp_clock *ptp);
+
+#endif
diff --git a/drivers/ptp/ptp_sysfs.c b/drivers/ptp/ptp_sysfs.c
new file mode 100644
index 0000000..2f93926
--- /dev/null
+++ b/drivers/ptp/ptp_sysfs.c
@@ -0,0 +1,230 @@
+/*
+ * PTP 1588 clock support - sysfs interface.
+ *
+ * Copyright (C) 2010 OMICRON electronics GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <linux/capability.h>
+
+#include "ptp_private.h"
+
+static ssize_t clock_name_show(struct device *dev,
+ struct device_attribute *attr, char *page)
+{
+ struct ptp_clock *ptp = dev_get_drvdata(dev);
+ return snprintf(page, PAGE_SIZE-1, "%s\n", ptp->info->name);
+}
+
+#define PTP_SHOW_INT(name) \
+static ssize_t name##_show(struct device *dev, \
+ struct device_attribute *attr, char *page) \
+{ \
+ struct ptp_clock *ptp = dev_get_drvdata(dev); \
+ return snprintf(page, PAGE_SIZE-1, "%d\n", ptp->info->name); \
+}
+
+PTP_SHOW_INT(max_adj);
+PTP_SHOW_INT(n_alarm);
+PTP_SHOW_INT(n_ext_ts);
+PTP_SHOW_INT(n_per_out);
+PTP_SHOW_INT(pps);
+
+#define PTP_RO_ATTR(_var, _name) { \
+ .attr = { .name = __stringify(_name), .mode = 0444 }, \
+ .show = _var##_show, \
+}
+
+struct device_attribute ptp_dev_attrs[] = {
+ PTP_RO_ATTR(clock_name, clock_name),
+ PTP_RO_ATTR(max_adj, max_adjustment),
+ PTP_RO_ATTR(n_alarm, n_alarms),
+ PTP_RO_ATTR(n_ext_ts, n_external_timestamps),
+ PTP_RO_ATTR(n_per_out, n_periodic_outputs),
+ PTP_RO_ATTR(pps, pps_available),
+ __ATTR_NULL,
+};
+
+static ssize_t extts_enable_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct ptp_clock *ptp = dev_get_drvdata(dev);
+ struct ptp_clock_info *ops = ptp->info;
+ struct ptp_clock_request req = { .type = PTP_CLK_REQ_EXTTS };
+ int cnt, enable;
+ int err = -EINVAL;
+
+ cnt = sscanf(buf, "%u %d", &req.extts.index, &enable);
+ if (cnt != 2)
+ goto out;
+ if (req.extts.index >= ops->n_ext_ts)
+ goto out;
+
+ err = ops->enable(ops, &req, enable ? 1 : 0);
+ if (err)
+ goto out;
+
+ return count;
+out:
+ return err;
+}
+
+static ssize_t extts_fifo_show(struct device *dev,
+ struct device_attribute *attr, char *page)
+{
+ struct ptp_clock *ptp = dev_get_drvdata(dev);
+ struct timestamp_event_queue *queue = &ptp->tsevq;
+ struct ptp_extts_event event;
+ unsigned long flags;
+ size_t qcnt;
+ int cnt = 0;
+
+ memset(&event, 0, sizeof(event));
+
+ if (mutex_lock_interruptible(&ptp->tsevq_mux))
+ return -ERESTARTSYS;
+
+ spin_lock_irqsave(&queue->lock, flags);
+ qcnt = queue_cnt(queue);
+ if (qcnt) {
+ event = queue->buf[queue->head];
+ queue->head = (queue->head + 1) % PTP_MAX_TIMESTAMPS;
+ }
+ spin_unlock_irqrestore(&queue->lock, flags);
+
+ if (!qcnt)
+ goto out;
+
+ cnt = snprintf(page, PAGE_SIZE, "%u %lld %u\n",
+ event.index, event.t.sec, event.t.nsec);
+out:
+ mutex_unlock(&ptp->tsevq_mux);
+ return cnt;
+}
+
+static ssize_t period_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct ptp_clock *ptp = dev_get_drvdata(dev);
+ struct ptp_clock_info *ops = ptp->info;
+ struct ptp_clock_request req = { .type = PTP_CLK_REQ_PEROUT };
+ int cnt, enable, err = -EINVAL;
+
+ cnt = sscanf(buf, "%u %lld %u %lld %u", &req.perout.index,
+ &req.perout.start.sec, &req.perout.start.nsec,
+ &req.perout.period.sec, &req.perout.period.nsec);
+ if (cnt != 5)
+ goto out;
+ if (req.perout.index >= ops->n_per_out)
+ goto out;
+
+ enable = req.perout.period.sec || req.perout.period.nsec;
+ err = ops->enable(ops, &req, enable);
+ if (err)
+ goto out;
+
+ return count;
+out:
+ return err;
+}
+
+static ssize_t pps_enable_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct ptp_clock *ptp = dev_get_drvdata(dev);
+ struct ptp_clock_info *ops = ptp->info;
+ struct ptp_clock_request req = { .type = PTP_CLK_REQ_PPS };
+ int cnt, enable;
+ int err = -EINVAL;
+
+ if (!capable(CAP_SYS_TIME))
+ return -EPERM;
+
+ cnt = sscanf(buf, "%d", &enable);
+ if (cnt != 1)
+ goto out;
+
+ err = ops->enable(ops, &req, enable ? 1 : 0);
+ if (err)
+ goto out;
+
+ return count;
+out:
+ return err;
+}
+
+static DEVICE_ATTR(extts_enable, 0220, NULL, extts_enable_store);
+static DEVICE_ATTR(fifo, 0444, extts_fifo_show, NULL);
+static DEVICE_ATTR(period, 0220, NULL, period_store);
+static DEVICE_ATTR(pps_enable, 0220, NULL, pps_enable_store);
+
+int ptp_cleanup_sysfs(struct ptp_clock *ptp)
+{
+ struct device *dev = ptp->dev;
+ struct ptp_clock_info *info = ptp->info;
+
+ if (info->n_ext_ts) {
+ device_remove_file(dev, &dev_attr_extts_enable);
+ device_remove_file(dev, &dev_attr_fifo);
+ }
+ if (info->n_per_out)
+ device_remove_file(dev, &dev_attr_period);
+
+ if (info->pps)
+ device_remove_file(dev, &dev_attr_pps_enable);
+
+ return 0;
+}
+
+int ptp_populate_sysfs(struct ptp_clock *ptp)
+{
+ struct device *dev = ptp->dev;
+ struct ptp_clock_info *info = ptp->info;
+ int err;
+
+ if (info->n_ext_ts) {
+ err = device_create_file(dev, &dev_attr_extts_enable);
+ if (err)
+ goto out1;
+ err = device_create_file(dev, &dev_attr_fifo);
+ if (err)
+ goto out2;
+ }
+ if (info->n_per_out) {
+ err = device_create_file(dev, &dev_attr_period);
+ if (err)
+ goto out3;
+ }
+ if (info->pps) {
+ err = device_create_file(dev, &dev_attr_pps_enable);
+ if (err)
+ goto out4;
+ }
+ return 0;
+out4:
+ if (info->n_per_out)
+ device_remove_file(dev, &dev_attr_period);
+out3:
+ if (info->n_ext_ts)
+ device_remove_file(dev, &dev_attr_fifo);
+out2:
+ if (info->n_ext_ts)
+ device_remove_file(dev, &dev_attr_extts_enable);
+out1:
+ return err;
+}
diff --git a/include/linux/Kbuild b/include/linux/Kbuild
index 75cf611..4585836 100644
--- a/include/linux/Kbuild
+++ b/include/linux/Kbuild
@@ -302,6 +302,7 @@ header-y += ppp-comp.h
header-y += ppp_defs.h
header-y += pps.h
header-y += prctl.h
+header-y += ptp_clock.h
header-y += ptrace.h
header-y += qnx4_fs.h
header-y += qnxtypes.h
diff --git a/include/linux/ptp_classify.h b/include/linux/ptp_classify.h
index 943a85a..e07e274 100644
--- a/include/linux/ptp_classify.h
+++ b/include/linux/ptp_classify.h
@@ -25,6 +25,7 @@
#include <linux/if_ether.h>
#include <linux/if_vlan.h>
+#include <linux/ip.h>
#include <linux/filter.h>
#ifdef __KERNEL__
#include <linux/in.h>
@@ -58,6 +59,12 @@
#define OFF_NEXT 6
#define OFF_UDP_DST 2
+#define OFF_PTP_SOURCE_UUID 22 /* PTPv1 only */
+#define OFF_PTP_SEQUENCE_ID 30
+#define OFF_PTP_CONTROL 32 /* PTPv1 only */
+
+#define IPV4_HLEN(data) (((struct iphdr *)(data + OFF_IHL))->ihl << 2)
+
#define IP6_HLEN 40
#define UDP_HLEN 8
diff --git a/include/linux/ptp_clock.h b/include/linux/ptp_clock.h
new file mode 100644
index 0000000..94e981f
--- /dev/null
+++ b/include/linux/ptp_clock.h
@@ -0,0 +1,84 @@
+/*
+ * PTP 1588 clock support - user space interface
+ *
+ * Copyright (C) 2010 OMICRON electronics GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#ifndef _PTP_CLOCK_H_
+#define _PTP_CLOCK_H_
+
+#include <linux/ioctl.h>
+#include <linux/types.h>
+
+/* PTP_xxx bits, for the flags field within the request structures. */
+#define PTP_ENABLE_FEATURE (1<<0)
+#define PTP_RISING_EDGE (1<<1)
+#define PTP_FALLING_EDGE (1<<2)
+
+/*
+ * struct ptp_clock_time - represents a time value
+ *
+ * The sign of the seconds field applies to the whole value. The
+ * nanoseconds field is always unsigned. The reserved field is
+ * included for sub-nanosecond resolution, should the demand for
+ * this ever appear.
+ *
+ */
+struct ptp_clock_time {
+ __s64 sec; /* seconds */
+ __u32 nsec; /* nanoseconds */
+ __u32 reserved;
+};
+
+struct ptp_clock_caps {
+ int max_adj; /* Maximum frequency adjustment in parts per billon. */
+ int n_alarm; /* Number of programmable alarms. */
+ int n_ext_ts; /* Number of external time stamp channels. */
+ int n_per_out; /* Number of programmable periodic signals. */
+ int pps; /* Whether the clock supports a PPS callback. */
+ int rsv[15]; /* Reserved for future use. */
+};
+
+struct ptp_extts_request {
+ unsigned int index; /* Which channel to configure. */
+ unsigned int flags; /* Bit field for PTP_xxx flags. */
+ unsigned int rsv[2]; /* Reserved for future use. */
+};
+
+struct ptp_perout_request {
+ struct ptp_clock_time start; /* Absolute start time. */
+ struct ptp_clock_time period; /* Desired period, zero means disable. */
+ unsigned int index; /* Which channel to configure. */
+ unsigned int flags; /* Reserved for future use. */
+ unsigned int rsv[4]; /* Reserved for future use. */
+};
+
+#define PTP_CLK_MAGIC '='
+
+#define PTP_CLOCK_GETCAPS _IOR(PTP_CLK_MAGIC, 1, struct ptp_clock_caps)
+#define PTP_EXTTS_REQUEST _IOW(PTP_CLK_MAGIC, 2, struct ptp_extts_request)
+#define PTP_PEROUT_REQUEST _IOW(PTP_CLK_MAGIC, 3, struct ptp_perout_request)
+#define PTP_ENABLE_PPS _IOW(PTP_CLK_MAGIC, 4, int)
+
+struct ptp_extts_event {
+ struct ptp_clock_time t; /* Time event occured. */
+ unsigned int index; /* Which channel produced the event. */
+ unsigned int flags; /* Reserved for future use. */
+ unsigned int rsv[2]; /* Reserved for future use. */
+};
+
+#endif
diff --git a/include/linux/ptp_clock_kernel.h b/include/linux/ptp_clock_kernel.h
new file mode 100644
index 0000000..dd2e44f
--- /dev/null
+++ b/include/linux/ptp_clock_kernel.h
@@ -0,0 +1,139 @@
+/*
+ * PTP 1588 clock support
+ *
+ * Copyright (C) 2010 OMICRON electronics GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#ifndef _PTP_CLOCK_KERNEL_H_
+#define _PTP_CLOCK_KERNEL_H_
+
+#include <linux/ptp_clock.h>
+
+
+struct ptp_clock_request {
+ enum {
+ PTP_CLK_REQ_EXTTS,
+ PTP_CLK_REQ_PEROUT,
+ PTP_CLK_REQ_PPS,
+ } type;
+ union {
+ struct ptp_extts_request extts;
+ struct ptp_perout_request perout;
+ };
+};
+
+/**
+ * struct ptp_clock_info - decribes a PTP hardware clock
+ *
+ * @owner: The clock driver should set to THIS_MODULE.
+ * @name: A short name to identify the clock.
+ * @max_adj: The maximum possible frequency adjustment, in parts per billon.
+ * @n_alarm: The number of programmable alarms.
+ * @n_ext_ts: The number of external time stamp channels.
+ * @n_per_out: The number of programmable periodic signals.
+ * @pps: Indicates whether the clock supports a PPS callback.
+ *
+ * clock operations
+ *
+ * @adjfreq: Adjusts the frequency of the hardware clock.
+ * parameter delta: Desired period change in parts per billion.
+ *
+ * @adjtime: Shifts the time of the hardware clock.
+ * parameter delta: Desired change in nanoseconds.
+ *
+ * @gettime: Reads the current time from the hardware clock.
+ * parameter ts: Holds the result.
+ *
+ * @settime: Set the current time on the hardware clock.
+ * parameter ts: Time value to set.
+ *
+ * @enable: Request driver to enable or disable an ancillary feature.
+ * parameter request: Desired resource to enable or disable.
+ * parameter on: Caller passes one to enable or zero to disable.
+ *
+ * Drivers should embed their ptp_clock_info within a private
+ * structure, obtaining a reference to it using container_of().
+ *
+ * The callbacks must all return zero on success, non-zero otherwise.
+ */
+
+struct ptp_clock_info {
+ struct module *owner;
+ char name[16];
+ s32 max_adj;
+ int n_alarm;
+ int n_ext_ts;
+ int n_per_out;
+ int pps;
+ int (*adjfreq)(struct ptp_clock_info *ptp, s32 delta);
+ int (*adjtime)(struct ptp_clock_info *ptp, s64 delta);
+ int (*gettime)(struct ptp_clock_info *ptp, struct timespec *ts);
+ int (*settime)(struct ptp_clock_info *ptp, const struct timespec *ts);
+ int (*enable)(struct ptp_clock_info *ptp,
+ struct ptp_clock_request *request, int on);
+};
+
+struct ptp_clock;
+
+/**
+ * ptp_clock_register() - register a PTP hardware clock driver
+ *
+ * @info: Structure describing the new clock.
+ */
+
+extern struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info);
+
+/**
+ * ptp_clock_unregister() - unregister a PTP hardware clock driver
+ *
+ * @ptp: The clock to remove from service.
+ */
+
+extern int ptp_clock_unregister(struct ptp_clock *ptp);
+
+
+enum ptp_clock_events {
+ PTP_CLOCK_ALARM,
+ PTP_CLOCK_EXTTS,
+ PTP_CLOCK_PPS,
+};
+
+/**
+ * struct ptp_clock_event - decribes a PTP hardware clock event
+ *
+ * @type: One of the ptp_clock_events enumeration values.
+ * @index: Identifies the source of the event.
+ * @timestamp: When the event occured.
+ */
+
+struct ptp_clock_event {
+ int type;
+ int index;
+ u64 timestamp;
+};
+
+/**
+ * ptp_clock_event() - notify the PTP layer about an event
+ *
+ * @ptp: The clock obtained from ptp_clock_register().
+ * @event: Message structure describing the event.
+ */
+
+extern void ptp_clock_event(struct ptp_clock *ptp,
+ struct ptp_clock_event *event);
+
+#endif
--
1.7.0.4
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