[PATCH 1/5] ptp: Added a brand new class driver for ptp clocks.
Richard Cochran
richardcochran at gmail.com
Mon Aug 16 07:17:36 EDT 2010
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
exposed to user space as a character device with ioctls that allow tuning
of the PTP clock.
Signed-off-by: Richard Cochran <richard.cochran at omicron.at>
---
Documentation/ptp/ptp.txt | 95 +++++++
Documentation/ptp/testptp.c | 306 ++++++++++++++++++++++
Documentation/ptp/testptp.mk | 33 +++
drivers/Kconfig | 2 +
drivers/Makefile | 1 +
drivers/ptp/Kconfig | 27 ++
drivers/ptp/Makefile | 5 +
drivers/ptp/ptp_clock.c | 514 ++++++++++++++++++++++++++++++++++++++
include/linux/Kbuild | 1 +
include/linux/ptp_clock.h | 79 ++++++
include/linux/ptp_clock_kernel.h | 137 ++++++++++
11 files changed, 1200 insertions(+), 0 deletions(-)
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_clock.c
create mode 100644 include/linux/ptp_clock.h
create mode 100644 include/linux/ptp_clock_kernel.h
diff --git a/Documentation/ptp/ptp.txt b/Documentation/ptp/ptp.txt
new file mode 100644
index 0000000..46858b3
--- /dev/null
+++ b/Documentation/ptp/ptp.txt
@@ -0,0 +1,95 @@
+
+* PTP 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 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 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 user space API
+
+ The class driver creates a character device for each registered PTP
+ clock. 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 an ioctl API with semantics similar
+ to the POSIX timer_settime() system call.
+
+ As an real life example, the following two patches for ptpd version
+ 1.0.0 demonstrate how the API works.
+
+ https://sourceforge.net/tracker/?func=detail&aid=2992845&group_id=139814&atid=744634
+
+ https://sourceforge.net/tracker/?func=detail&aid=2992847&group_id=139814&atid=744634
+
+** 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
+
+ + Standard Linux system timer
+ - No special PTP features
+ - For use with software time stamping
+
+ + 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..41a9839
--- /dev/null
+++ b/Documentation/ptp/testptp.c
@@ -0,0 +1,306 @@
+/*
+ * 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 <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/types.h>
+#include <time.h>
+#include <unistd.h>
+
+#include <linux/ptp_clock.h>
+
+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 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"
+ " -t val shift the ptp clock time by 'val' seconds\n"
+ " -v query the ptp clock api version\n",
+ progname);
+}
+
+int main(int argc, char *argv[])
+{
+ struct ptp_clock_caps caps;
+ struct ptp_clock_timer timer;
+ struct ptp_extts_event event;
+ struct ptp_clock_request request;
+ struct timespec ts;
+ char *progname;
+ int c, cnt, fd, val = 0;
+
+ char *device = "/dev/ptp_clock_0";
+ 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;
+ int version = 0;
+
+ progname = strrchr(argv[0], '/');
+ progname = progname ? 1+progname : argv[0];
+ while (EOF != (c = getopt(argc, argv, "a:A:cd:e:f:ghp:P:st: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 't':
+ adjtime = atoi(optarg);
+ break;
+ case 'v':
+ version = 1;
+ break;
+ case 'h':
+ usage(progname);
+ return 0;
+ case '?':
+ default:
+ usage(progname);
+ return -1;
+ }
+ }
+
+ fd = open(device, O_RDWR);
+ if (fd < 0) {
+ fprintf(stderr, "cannot open %s: %s", device, strerror(errno));
+ return -1;
+ }
+
+ if (version) {
+ if (ioctl(fd, PTP_CLOCK_APIVERS, &val)) {
+ perror("PTP_CLOCK_APIVERS");
+ } else {
+ printf("version = 0x%08x\n", val);
+ }
+ }
+
+ 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) {
+ if (ioctl(fd, PTP_CLOCK_ADJFREQ, adjfreq)) {
+ perror("PTP_CLOCK_ADJFREQ");
+ } else {
+ puts("frequency adjustment okay");
+ }
+ }
+
+ if (adjtime) {
+ ts.tv_sec = adjtime;
+ ts.tv_nsec = 0;
+ if (ioctl(fd, PTP_CLOCK_ADJTIME, &ts)) {
+ perror("PTP_CLOCK_ADJTIME");
+ } else {
+ puts("time shift okay");
+ }
+ }
+
+ if (gettime) {
+ if (ioctl(fd, PTP_CLOCK_GETTIME, &ts)) {
+ perror("PTP_CLOCK_GETTIME");
+ } else {
+ printf("clock time: %ld.%09ld or %s",
+ ts.tv_sec, ts.tv_nsec, ctime(&ts.tv_sec));
+ }
+ }
+
+ if (settime) {
+ clock_gettime(CLOCK_REALTIME, &ts);
+ if (ioctl(fd, PTP_CLOCK_SETTIME, &ts)) {
+ perror("PTP_CLOCK_SETTIME");
+ } else {
+ puts("set time okay");
+ }
+ }
+
+ if (extts) {
+ memset(&request, 0, sizeof(request));
+ request.type = PTP_REQUEST_EXTTS;
+ request.index = 0;
+ request.flags = PTP_ENABLE_FEATURE;
+ if (ioctl(fd, PTP_FEATURE_REQUEST, &request)) {
+ perror("PTP_FEATURE_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 %d at %ld.%09ld\n", event.index,
+ event.ts.tv_sec, event.ts.tv_nsec);
+ fflush(stdout);
+ }
+ /* Disable the feature again. */
+ request.flags = 0;
+ if (ioctl(fd, PTP_FEATURE_REQUEST, &request)) {
+ perror("PTP_FEATURE_REQUEST");
+ }
+ }
+
+ if (oneshot) {
+ install_handler(SIGALRM, handle_alarm);
+ memset(&timer, 0, sizeof(timer));
+ timer.signum = SIGALRM;
+ timer.tsp.it_value.tv_sec = oneshot;
+ if (ioctl(fd, PTP_CLOCK_SETTIMER, &timer)) {
+ perror("PTP_CLOCK_SETTIMER");
+ } else {
+ puts("set timer okay");
+ }
+ pause();
+ }
+
+ if (periodic) {
+ install_handler(SIGALRM, handle_alarm);
+ memset(&timer, 0, sizeof(timer));
+ timer.signum = SIGALRM;
+ timer.tsp.it_value.tv_sec = periodic;
+ timer.tsp.it_interval.tv_sec = periodic;
+ if (ioctl(fd, PTP_CLOCK_SETTIMER, &timer)) {
+ perror("PTP_CLOCK_SETTIMER");
+ } else {
+ puts("set timer okay");
+ }
+ while (1) {
+ pause();
+ }
+ }
+
+ if (perout >= 0) {
+ memset(&request, 0, sizeof(request));
+ request.type = PTP_REQUEST_PEROUT;
+ request.index = 0;
+ request.ts.tv_sec = 0;
+ request.ts.tv_nsec = perout;
+ request.flags = perout ? PTP_ENABLE_FEATURE : 0;
+ if (ioctl(fd, PTP_FEATURE_REQUEST, &request)) {
+ perror("PTP_FEATURE_REQUEST");
+ extts = 0;
+ } else {
+ puts("periodic output request okay");
+ }
+ }
+
+ if (pps != -1) {
+ memset(&request, 0, sizeof(request));
+ request.type = PTP_REQUEST_PPS;
+ request.flags = perout ? PTP_ENABLE_FEATURE : 0;
+ if (ioctl(fd, PTP_FEATURE_REQUEST, &request)) {
+ perror("PTP_FEATURE_REQUEST");
+ } 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 $(PROGS)
diff --git a/drivers/Kconfig b/drivers/Kconfig
index a2b902f..774fbd7 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -52,6 +52,8 @@ source "drivers/spi/Kconfig"
source "drivers/pps/Kconfig"
+source "drivers/ptp/Kconfig"
+
source "drivers/gpio/Kconfig"
source "drivers/w1/Kconfig"
diff --git a/drivers/Makefile b/drivers/Makefile
index 91874e0..6d12b48 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -76,6 +76,7 @@ obj-$(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..cd7becb
--- /dev/null
+++ b/drivers/ptp/Kconfig
@@ -0,0 +1,27 @@
+#
+# PTP clock support configuration
+#
+
+menu "PTP clock support"
+
+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_clock.
+
+endmenu
diff --git a/drivers/ptp/Makefile b/drivers/ptp/Makefile
new file mode 100644
index 0000000..b86695c
--- /dev/null
+++ b/drivers/ptp/Makefile
@@ -0,0 +1,5 @@
+#
+# Makefile for PTP 1588 clock support.
+#
+
+obj-$(CONFIG_PTP_1588_CLOCK) += ptp_clock.o
diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c
new file mode 100644
index 0000000..1ebb4b0
--- /dev/null
+++ b/drivers/ptp/ptp_clock.c
@@ -0,0 +1,514 @@
+/*
+ * PTP 1588 clock support
+ *
+ * Partially adapted from the Linux PPS driver.
+ *
+ * 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/cdev.h>
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/poll.h>
+#include <linux/pps_kernel.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+
+#include <linux/ptp_clock_kernel.h>
+#include <linux/ptp_clock.h>
+
+#define PTP_MAX_ALARMS 4
+#define PTP_MAX_CLOCKS BITS_PER_LONG
+#define PTP_MAX_TIMESTAMPS 128
+#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)
+
+struct alarm {
+ struct pid *pid;
+ int sig;
+};
+
+struct timestamp_event_queue {
+ struct ptp_extts_event buf[PTP_MAX_TIMESTAMPS];
+ int head;
+ int tail;
+ int overflow;
+};
+
+struct ptp_clock {
+ struct list_head list;
+ struct cdev cdev;
+ struct device *dev;
+ struct ptp_clock_info *info;
+ dev_t devid;
+ int index; /* index into clocks.map, also the minor number */
+ int pps_source;
+
+ struct alarm alarm[PTP_MAX_ALARMS];
+ struct mutex alarm_mux; /* one process at a time setting an alarm */
+
+ 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;
+};
+
+/* private globals */
+
+static const struct file_operations ptp_fops;
+static dev_t ptp_devt;
+static struct class *ptp_class;
+
+static struct {
+ struct list_head list;
+ DECLARE_BITMAP(map, PTP_MAX_CLOCKS);
+} clocks;
+static DEFINE_MUTEX(clocks_mux); /* protects 'clocks' */
+
+/* time stamp event queue operations */
+
+static inline int queue_cnt(struct timestamp_event_queue *q)
+{
+ int cnt = q->tail - q->head;
+ return cnt < 0 ? PTP_MAX_TIMESTAMPS + cnt : cnt;
+}
+
+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;
+ u32 remainder;
+
+ dst = &queue->buf[queue->tail];
+
+ dst->index = src->index;
+ dst->ts.tv_sec = div_u64_rem(src->timestamp, 1000000000, &remainder);
+ dst->ts.tv_nsec = remainder;
+
+ if (!queue_free(queue))
+ queue->overflow++;
+
+ queue->tail = (queue->tail + 1) % PTP_MAX_TIMESTAMPS;
+}
+
+/* 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(&clocks_mux);
+ index = find_first_zero_bit(clocks.map, PTP_MAX_CLOCKS);
+ if (index < PTP_MAX_CLOCKS)
+ set_bit(index, clocks.map);
+ else
+ goto no_clock;
+
+ /* Initialize a clock structure. */
+ err = -ENOMEM;
+ ptp = kzalloc(sizeof(struct ptp_clock), GFP_KERNEL);
+ if (ptp == NULL)
+ goto no_memory;
+
+ ptp->info = info;
+ ptp->devid = MKDEV(major, index);
+ ptp->index = index;
+ mutex_init(&ptp->alarm_mux);
+ 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_clock_%d", ptp->index);
+ if (IS_ERR(ptp->dev))
+ goto no_device;
+
+ dev_set_drvdata(ptp->dev, ptp);
+
+ /* Register a character device. */
+ cdev_init(&ptp->cdev, &ptp_fops);
+ ptp->cdev.owner = info->owner;
+ err = cdev_add(&ptp->cdev, ptp->devid, 1);
+ if (err)
+ goto no_cdev;
+
+ /* 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;
+ pps.dev = ptp->dev;
+ err = pps_register_source(&pps, PTP_PPS_DEFAULTS);
+ if (err < 0) {
+ pr_err("failed to register pps source\n");
+ goto no_pps;
+ } else
+ ptp->pps_source = err;
+ }
+
+ /* Clock is ready, add it into the list. */
+ list_add(&ptp->list, &clocks.list);
+
+ mutex_unlock(&clocks_mux);
+ return ptp;
+
+no_pps:
+no_cdev:
+ device_destroy(ptp_class, ptp->devid);
+no_device:
+ mutex_destroy(&ptp->alarm_mux);
+ mutex_destroy(&ptp->tsevq_mux);
+ kfree(ptp);
+no_memory:
+ clear_bit(index, clocks.map);
+no_clock:
+ mutex_unlock(&clocks_mux);
+ return ERR_PTR(err);
+}
+EXPORT_SYMBOL(ptp_clock_register);
+
+int ptp_clock_unregister(struct ptp_clock *ptp)
+{
+ /* Release the clock's resources. */
+ if (ptp->info->pps)
+ pps_unregister_source(ptp->pps_source);
+ cdev_del(&ptp->cdev);
+ device_destroy(ptp_class, ptp->devid);
+ mutex_destroy(&ptp->alarm_mux);
+ mutex_destroy(&ptp->tsevq_mux);
+
+ /* Remove the clock from the list. */
+ mutex_lock(&clocks_mux);
+ list_del(&ptp->list);
+ clear_bit(ptp->index, clocks.map);
+ mutex_unlock(&clocks_mux);
+
+ kfree(ptp);
+
+ return 0;
+}
+EXPORT_SYMBOL(ptp_clock_unregister);
+
+void ptp_clock_event(struct ptp_clock *ptp, struct ptp_clock_event *event)
+{
+ struct timespec ts;
+ struct pps_ktime pps_ts;
+
+ switch (event->type) {
+
+ case PTP_CLOCK_ALARM:
+ kill_pid(ptp->alarm[event->index].pid,
+ ptp->alarm[event->index].sig, 1);
+ break;
+
+ case PTP_CLOCK_EXTTS:
+ enqueue_external_timestamp(&ptp->tsevq, event);
+ wake_up_interruptible(&ptp->tsev_wq);
+ break;
+
+ case PTP_CLOCK_PPS:
+ getnstimeofday(&ts);
+ pps_ts.sec = ts.tv_sec;
+ pps_ts.nsec = ts.tv_nsec;
+ pps_event(ptp->pps_source, &pps_ts, PTP_PPS_EVENT, NULL);
+ break;
+ }
+}
+EXPORT_SYMBOL(ptp_clock_event);
+
+/* character device operations */
+
+static int ptp_ioctl(struct inode *node, struct file *fp,
+ unsigned int cmd, unsigned long arg)
+{
+ struct ptp_clock_caps caps;
+ struct ptp_clock_request req;
+ struct ptp_clock_timer timer;
+ struct ptp_clock *ptp = fp->private_data;
+ struct ptp_clock_info *ops = ptp->info;
+ void *priv = ops->priv;
+ struct timespec ts;
+ int flags, index;
+ int err = 0;
+ s32 ppb;
+
+ switch (cmd) {
+
+ case PTP_CLOCK_APIVERS:
+ err = put_user(PTP_CLOCK_VERSION, (u32 __user *)arg);
+ break;
+
+ case PTP_CLOCK_ADJFREQ:
+ if (!capable(CAP_SYS_TIME))
+ return -EPERM;
+ ppb = arg;
+ if (ppb > ops->max_adj || ppb < -ops->max_adj)
+ return -EINVAL;
+ err = ops->adjfreq(priv, ppb);
+ break;
+
+ case PTP_CLOCK_ADJTIME:
+ if (!capable(CAP_SYS_TIME))
+ return -EPERM;
+ if (copy_from_user(&ts, (void __user *)arg, sizeof(ts)))
+ err = -EFAULT;
+ else
+ err = ops->adjtime(priv, &ts);
+ break;
+
+ case PTP_CLOCK_GETTIME:
+ err = ops->gettime(priv, &ts);
+ if (err)
+ break;
+ err = copy_to_user((void __user *)arg, &ts, sizeof(ts));
+ break;
+
+ case PTP_CLOCK_SETTIME:
+ if (!capable(CAP_SYS_TIME))
+ return -EPERM;
+ if (copy_from_user(&ts, (void __user *)arg, sizeof(ts)))
+ err = -EFAULT;
+ else
+ err = ops->settime(priv, &ts);
+ break;
+
+ 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_CLOCK_GETTIMER:
+ if (copy_from_user(&timer, (void __user *)arg, sizeof(timer))) {
+ err = -EFAULT;
+ break;
+ }
+ index = timer.alarm_index;
+ if (index < 0 || index >= ptp->info->n_alarm) {
+ err = -EINVAL;
+ break;
+ }
+ err = ops->gettimer(priv, index, &timer.tsp);
+ if (err)
+ break;
+ err = copy_to_user((void __user *)arg, &timer, sizeof(timer));
+ break;
+
+ case PTP_CLOCK_SETTIMER:
+ if (copy_from_user(&timer, (void __user *)arg, sizeof(timer))) {
+ err = -EFAULT;
+ break;
+ }
+ index = timer.alarm_index;
+ if (index < 0 || index >= ptp->info->n_alarm) {
+ err = -EINVAL;
+ break;
+ }
+ if (!valid_signal(timer.signum))
+ return -EINVAL;
+ flags = timer.flags;
+ if (flags & (flags != TIMER_ABSTIME)) {
+ err = -EINVAL;
+ break;
+ }
+ if (mutex_lock_interruptible(&ptp->alarm_mux))
+ return -ERESTARTSYS;
+
+ if (ptp->alarm[index].pid)
+ put_pid(ptp->alarm[index].pid);
+
+ ptp->alarm[index].pid = get_pid(task_pid(current));
+ ptp->alarm[index].sig = timer.signum;
+ err = ops->settimer(priv, index, flags, &timer.tsp);
+
+ mutex_unlock(&ptp->alarm_mux);
+ break;
+
+ case PTP_FEATURE_REQUEST:
+ if (copy_from_user(&req, (void __user *)arg, sizeof(req))) {
+ err = -EFAULT;
+ break;
+ }
+ switch (req.type) {
+ case PTP_REQUEST_EXTTS:
+ case PTP_REQUEST_PEROUT:
+ break;
+ case PTP_REQUEST_PPS:
+ if (!capable(CAP_SYS_TIME))
+ return -EPERM;
+ break;
+ default:
+ err = -EINVAL;
+ break;
+ }
+ if (err)
+ break;
+ err = ops->enable(priv, &req,
+ req.flags & PTP_ENABLE_FEATURE ? 1 : 0);
+ break;
+
+ default:
+ err = -ENOTTY;
+ break;
+ }
+ return err;
+}
+
+static int ptp_open(struct inode *inode, struct file *fp)
+{
+ struct ptp_clock *ptp;
+ ptp = container_of(inode->i_cdev, struct ptp_clock, cdev);
+
+ fp->private_data = ptp;
+
+ return 0;
+}
+
+static unsigned int ptp_poll(struct file *fp, poll_table *wait)
+{
+ struct ptp_clock *ptp = fp->private_data;
+
+ poll_wait(fp, &ptp->tsev_wq, wait);
+
+ return queue_cnt(&ptp->tsevq) ? POLLIN : 0;
+}
+
+static ssize_t ptp_read(struct file *fp, char __user *buf,
+ size_t cnt, loff_t *off)
+{
+ struct ptp_clock *ptp = fp->private_data;
+ struct timestamp_event_queue *queue = &ptp->tsevq;
+ struct ptp_extts_event *event;
+ size_t qcnt;
+
+ if (mutex_lock_interruptible(&ptp->tsevq_mux))
+ return -ERESTARTSYS;
+
+ cnt = cnt / sizeof(struct ptp_extts_event);
+
+ if (wait_event_interruptible(ptp->tsev_wq,
+ (qcnt = queue_cnt(&ptp->tsevq)))) {
+ mutex_unlock(&ptp->tsevq_mux);
+ return -ERESTARTSYS;
+ }
+
+ if (cnt > qcnt)
+ cnt = qcnt;
+
+ event = &queue->buf[queue->head];
+
+ if (copy_to_user(buf, event, cnt * sizeof(struct ptp_extts_event))) {
+ mutex_unlock(&ptp->tsevq_mux);
+ return -EFAULT;
+ }
+ queue->head = (queue->head + cnt) % PTP_MAX_TIMESTAMPS;
+
+ mutex_unlock(&ptp->tsevq_mux);
+
+ return cnt * sizeof(struct ptp_extts_event);
+}
+
+static int ptp_release(struct inode *inode, struct file *fp)
+{
+ struct ptp_clock *ptp;
+ struct itimerspec ts = {
+ {0, 0}, {0, 0}
+ };
+ int i;
+
+ ptp = container_of(inode->i_cdev, struct ptp_clock, cdev);
+
+ for (i = 0; i < ptp->info->n_alarm; i++) {
+ if (ptp->alarm[i].pid) {
+ ptp->info->settimer(ptp->info->priv, i, 0, &ts);
+ put_pid(ptp->alarm[i].pid);
+ ptp->alarm[i].pid = NULL;
+ }
+ }
+ return 0;
+}
+
+static const struct file_operations ptp_fops = {
+ .owner = THIS_MODULE,
+ .ioctl = ptp_ioctl,
+ .open = ptp_open,
+ .poll = ptp_poll,
+ .read = ptp_read,
+ .release = ptp_release,
+};
+
+/* 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;
+
+ INIT_LIST_HEAD(&clocks.list);
+
+ ptp_class = class_create(THIS_MODULE, "ptp");
+ if (!ptp_class) {
+ printk(KERN_ERR "ptp: failed to allocate class\n");
+ return -ENOMEM;
+ }
+
+ err = alloc_chrdev_region(&ptp_devt, 0, PTP_MAX_CLOCKS, "ptp");
+ if (err < 0) {
+ printk(KERN_ERR "ptp: failed to allocate char device region\n");
+ goto no_region;
+ }
+
+ 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/include/linux/Kbuild b/include/linux/Kbuild
index 9aa9bca..471205a 100644
--- a/include/linux/Kbuild
+++ b/include/linux/Kbuild
@@ -140,6 +140,7 @@ header-y += pkt_sched.h
header-y += posix_types.h
header-y += ppdev.h
header-y += prctl.h
+header-y += ptp_clock.h
header-y += qnxtypes.h
header-y += qnx4_fs.h
header-y += radeonfb.h
diff --git a/include/linux/ptp_clock.h b/include/linux/ptp_clock.h
new file mode 100644
index 0000000..5a509c5
--- /dev/null
+++ b/include/linux/ptp_clock.h
@@ -0,0 +1,79 @@
+/*
+ * 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>
+
+#define PTP_ENABLE_FEATURE (1<<0)
+#define PTP_RISING_EDGE (1<<1)
+#define PTP_FALLING_EDGE (1<<2)
+
+enum ptp_request_types {
+ PTP_REQUEST_EXTTS,
+ PTP_REQUEST_PEROUT,
+ PTP_REQUEST_PPS,
+};
+
+struct ptp_clock_caps {
+ __s32 max_adj; /* Maximum frequency adjustment, 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. */
+};
+
+struct ptp_clock_timer {
+ int alarm_index; /* Which alarm to query or configure. */
+ int signum; /* Requested signal. */
+ int flags; /* Zero or TIMER_ABSTIME, see TIMER_SETTIME(2) */
+ struct itimerspec tsp; /* See TIMER_SETTIME(2) */
+};
+
+struct ptp_clock_request {
+ int type; /* One of the ptp_request_types enumeration values. */
+ int index; /* Which channel to configure. */
+ struct timespec ts; /* For period signals, the desired period. */
+ int flags; /* Bit field for PTP_ENABLE_FEATURE or other flags. */
+};
+
+struct ptp_extts_event {
+ int index;
+ struct timespec ts;
+};
+
+#define PTP_CLOCK_VERSION 0x00000001
+
+#define PTP_CLK_MAGIC '='
+
+#define PTP_CLOCK_APIVERS _IOR (PTP_CLK_MAGIC, 1, __u32)
+#define PTP_CLOCK_ADJFREQ _IO (PTP_CLK_MAGIC, 2)
+#define PTP_CLOCK_ADJTIME _IOW (PTP_CLK_MAGIC, 3, struct timespec)
+#define PTP_CLOCK_GETTIME _IOR (PTP_CLK_MAGIC, 4, struct timespec)
+#define PTP_CLOCK_SETTIME _IOW (PTP_CLK_MAGIC, 5, struct timespec)
+
+#define PTP_CLOCK_GETCAPS _IOR (PTP_CLK_MAGIC, 6, struct ptp_clock_caps)
+#define PTP_CLOCK_GETTIMER _IOWR (PTP_CLK_MAGIC, 7, struct ptp_clock_timer)
+#define PTP_CLOCK_SETTIMER _IOW (PTP_CLK_MAGIC, 8, struct ptp_clock_timer)
+#define PTP_FEATURE_REQUEST _IOW (PTP_CLK_MAGIC, 9, struct ptp_clock_request)
+
+#endif
diff --git a/include/linux/ptp_clock_kernel.h b/include/linux/ptp_clock_kernel.h
new file mode 100644
index 0000000..d6cc158
--- /dev/null
+++ b/include/linux/ptp_clock_kernel.h
@@ -0,0 +1,137 @@
+/*
+ * 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_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.
+ * @priv: Passed to the clock operations, for the driver's private use.
+ *
+ * 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 ts: Desired change in seconds and 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.
+ *
+ * @gettimer: Reads the time remaining from the given timer.
+ * parameter index: Which alarm to query.
+ * parameter ts: Holds the result.
+ *
+ * @settimer: Arms the given timer for periodic or one shot operation.
+ * parameter index: Which alarm to set.
+ * parameter abs: TIMER_ABSTIME, or zero for relative timer.
+ * parameter ts: Alarm time and period 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.
+ *
+ * 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;
+ void *priv;
+ int (*adjfreq)(void *priv, s32 delta);
+ int (*adjtime)(void *priv, struct timespec *ts);
+ int (*gettime)(void *priv, struct timespec *ts);
+ int (*settime)(void *priv, struct timespec *ts);
+ int (*gettimer)(void *priv, int index, struct itimerspec *ts);
+ int (*settimer)(void *priv, int index, int abs, struct itimerspec *ts);
+ int (*enable)(void *priv, 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
+ *
+ * This function should only be called from interrupt context.
+ *
+ * @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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