This patch set adds the PPS support into Linux.
PPS means "pulse per second" and its API is specified by RFC 2783
(Pulse-Per-Second API for UNIX-like Operating Systems, Version 1.0).
The code has been tested with the NTPD program
(http://www.eecis.udel.edu/~mills/ntp/html/index.html) and several GPS
antennae.
Rodolfo
--
Documentation/pps/Makefile | 2
b/Documentation/pps/Makefile | 27 +++
b/Documentation/pps/pps.txt | 171 ++++++++++++++++++++
b/Documentation/pps/ppsctl.c | 63 +++++++
b/Documentation/pps/ppsfind | 17 ++
b/Documentation/pps/ppstest.c | 152 ++++++++++++++++++
b/Documentation/pps/timepps.h | 196 +++++++++++++++++++++++
b/MAINTAINERS | 7
b/drivers/Kconfig | 2
b/drivers/Makefile | 1
b/drivers/char/lp.c | 61 +++++++
b/drivers/pps/Kconfig | 32 +++
b/drivers/pps/Makefile | 10 +
b/drivers/pps/clients/Kconfig | 18 ++
b/drivers/pps/clients/Makefile | 9 +
b/drivers/pps/clients/ktimer.c | 115 +++++++++++++
b/drivers/pps/kapi.c | 272 ++++++++++++++++++++++++++++++++
b/drivers/pps/pps.c | 342 +++++++++++++++++++++++++++++++++++++++++ b/drivers/pps/sysfs.c | 142 +++++++++++++++++
b/drivers/serial/8250.c | 2
b/drivers/serial/serial_core.c | 71 ++++++++
b/include/linux/Kbuild | 1
b/include/linux/parport.h | 13 +
b/include/linux/pps.h | 205 ++++++++++++++++++++++++
b/include/linux/serial_core.h | 31 ++-
drivers/pps/Kconfig | 2
drivers/pps/Makefile | 1
drivers/pps/clients/Kconfig | 20 ++
28 files changed, 1969 insertions(+), 16 deletions(-)
Here some utilities and examples about the PPS API and the LinuxPPS
support.
* ppsctl.c implements an useful testing program, while
* ppsfind tries to help the user into finding a specific PPS source by
using its name or path.
Signed-off-by: Rodolfo Giometti <[email protected]>
---
Documentation/pps/Makefile | 27 ++++++++
Documentation/pps/ppsfind | 17 +++++
Documentation/pps/ppstest.c | 151 +++++++++++++++++++++++++++++++++++++++++++
3 files changed, 195 insertions(+), 0 deletions(-)
create mode 100644 Documentation/pps/Makefile
create mode 100644 Documentation/pps/ppsfind
create mode 100644 Documentation/pps/ppstest.c
diff --git a/Documentation/pps/Makefile b/Documentation/pps/Makefile
new file mode 100644
index 0000000..af4f9b4
--- /dev/null
+++ b/Documentation/pps/Makefile
@@ -0,0 +1,27 @@
+TARGETS = ppstest
+
+CFLAGS += -Wall -O2 -D_GNU_SOURCE
+CFLAGS += -I .
+CFLAGS += -ggdb
+
+# -- Actions section --
+
+.PHONY : all depend dep
+
+all : .depend $(TARGETS)
+
+.depend depend dep :
+ $(CC) $(CFLAGS) -M $(TARGETS:=.c) > .depend
+
+ifeq (.depend,$(wildcard .depend))
+include .depend
+endif
+
+
+# -- Clean section --
+
+.PHONY : clean
+
+clean :
+ rm -f *.o *~ core .depend
+ rm -f ${TARGETS}
diff --git a/Documentation/pps/ppsfind b/Documentation/pps/ppsfind
new file mode 100644
index 0000000..93c0e17
--- /dev/null
+++ b/Documentation/pps/ppsfind
@@ -0,0 +1,17 @@
+#!/bin/sh
+
+SYS="/sys/class/pps/"
+
+if [ $# -lt 1 ] ; then
+ echo "usage: ppsfind <name>" >&2
+ exit 1
+fi
+
+for d in $(ls $SYS) ; do
+ if grep $1 $SYS/$d/name >& /dev/null || \
+ grep $1 $SYS/$d/path >& /dev/null ; then
+ echo "$d: name=$(cat $SYS/$d/name) path=$(cat $SYS/$d/path)"
+ fi
+done
+
+exit 0
diff --git a/Documentation/pps/ppstest.c b/Documentation/pps/ppstest.c
new file mode 100644
index 0000000..d125ffa
--- /dev/null
+++ b/Documentation/pps/ppstest.c
@@ -0,0 +1,151 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#include <timepps.h>
+
+int find_source(char *path, pps_handle_t *handle, int *avail_mode)
+{
+ pps_params_t params;
+ int ret;
+
+ printf("trying PPS source \"%s\"\n", path);
+
+ /* Try to find the source by using the supplied "path" name */
+ ret = open(path, O_RDWR);
+ if (ret < 0) {
+ fprintf(stderr, "unable to open device \"%s\" (%m)\n", path);
+ return ret;
+ }
+
+ /* Open the PPS source (and check the file descriptor) */
+ ret = time_pps_create(ret, handle);
+ if (ret < 0) {
+ fprintf(stderr, "cannot create a PPS source from device "
+ "\"%s\" (%m)\n", path);
+ return -1;
+ }
+ printf("found PPS source \"%s\"\n", path);
+
+ /* Find out what features are supported */
+ ret = time_pps_getcap(*handle, avail_mode);
+ if (ret < 0) {
+ fprintf(stderr, "cannot get capabilities (%m)\n");
+ return -1;
+ }
+ if ((*avail_mode & PPS_CAPTUREASSERT) == 0) {
+ fprintf(stderr, "cannot CAPTUREASSERT\n");
+ return -1;
+ }
+ if ((*avail_mode & PPS_OFFSETASSERT) == 0) {
+ fprintf(stderr, "cannot OFFSETASSERT\n");
+ return -1;
+ }
+
+ /* Capture assert timestamps, and compensate for a 675 nsec
+ * propagation delay */
+ ret = time_pps_getparams(*handle, ¶ms);
+ if (ret < 0) {
+ fprintf(stderr, "cannot get parameters (%m)\n");
+ return -1;
+ }
+ params.assert_offset.tv_sec = 0;
+ params.assert_offset.tv_nsec = 675;
+ params.mode |= PPS_CAPTUREASSERT | PPS_OFFSETASSERT;
+ ret = time_pps_setparams(*handle, ¶ms);
+ if (ret < 0) {
+ fprintf(stderr, "cannot set parameters (%m)\n");
+ return -1;
+ }
+
+ return 0;
+}
+
+int fetch_source(int i, pps_handle_t *handle, int *avail_mode)
+{
+ struct timespec timeout;
+ pps_info_t infobuf;
+ int ret;
+
+ /* create a zero-valued timeout */
+ timeout.tv_sec = 3;
+ timeout.tv_nsec = 0;
+
+retry:
+ if (*avail_mode & PPS_CANWAIT) /* waits for the next event */
+ ret = time_pps_fetch(*handle, PPS_TSFMT_TSPEC, &infobuf,
+ &timeout);
+ else {
+ sleep(1);
+ ret = time_pps_fetch(*handle, PPS_TSFMT_TSPEC, &infobuf,
+ &timeout);
+ }
+ if (ret < 0) {
+ if (ret == -EINTR) {
+ fprintf(stderr, "time_pps_fetch() got a signal!\n");
+ goto retry;
+ }
+
+ fprintf(stderr, "time_pps_fetch() error %d (%m)\n", ret);
+ return -1;
+ }
+
+ printf("source %d - "
+ "assert %ld.%09ld, sequence: %ld - "
+ "clear %ld.%09ld, sequence: %ld\n",
+ i,
+ infobuf.assert_timestamp.tv_sec,
+ infobuf.assert_timestamp.tv_nsec,
+ infobuf.assert_sequence,
+ infobuf.clear_timestamp.tv_sec,
+ infobuf.clear_timestamp.tv_nsec, infobuf.clear_sequence);
+
+ return 0;
+}
+
+void usage(char *name)
+{
+ fprintf(stderr, "usage: %s <ppsdev> [<ppsdev> ...]\n", name);
+ exit(EXIT_FAILURE);
+}
+
+int main(int argc, char *argv[])
+{
+ int num;
+ pps_handle_t handle[4];
+ int avail_mode[4];
+ int i = 0;
+ int ret;
+
+ /* Check the command line */
+ if (argc < 2)
+ usage(argv[0]);
+
+ for (i = 1; i < argc && i <= 4; i++) {
+ ret = find_source(argv[i], &handle[i - 1], &avail_mode[i - 1]);
+ if (ret < 0)
+ exit(EXIT_FAILURE);
+ }
+
+ num = i - 1;
+ printf("ok, found %d source(s), now start fetching data...\n", num);
+
+ /* loop, printing the most recent timestamp every second or so */
+ while (1) {
+ for (i = 0; i < num; i++) {
+ ret = fetch_source(i, &handle[i], &avail_mode[i]);
+ if (ret < 0 && errno != ETIMEDOUT)
+ exit(EXIT_FAILURE);
+ }
+ }
+
+ for (; i >= 0; i--)
+ time_pps_destroy(handle[i]);
+
+ return 0;
+}
--
1.5.2.5
Adds support for the PPS sources connected with the interrupt pin of a
parallel port.
Signed-off-by: Rodolfo Giometti <[email protected]>
---
drivers/char/lp.c | 61 +++++++++++++++++++++++++++++++++++++++++++
drivers/pps/clients/Kconfig | 10 +++++++
include/linux/parport.h | 12 ++++++++
3 files changed, 83 insertions(+), 0 deletions(-)
diff --git a/drivers/char/lp.c b/drivers/char/lp.c
index 81674d7..edc5f9d 100644
--- a/drivers/char/lp.c
+++ b/drivers/char/lp.c
@@ -746,6 +746,27 @@ static struct console lpcons = {
#endif /* console on line printer */
+/* Support for PPS signal on the line printer */
+
+#ifdef CONFIG_PPS_CLIENT_LP
+
+static void lp_pps_echo(int source, int event, void *data)
+{
+ struct parport *port = data;
+ unsigned char status = parport_read_status(port);
+
+ /* echo event via SEL bit */
+ parport_write_control(port,
+ parport_read_control(port) | PARPORT_CONTROL_SELECT);
+
+ /* signal no event */
+ if ((status & PARPORT_STATUS_ACK) != 0)
+ parport_write_control(port,
+ parport_read_control(port) & ~PARPORT_CONTROL_SELECT);
+}
+
+#endif
+
/* --- initialisation code ------------------------------------- */
static int parport_nr[LP_NO] = { [0 ... LP_NO-1] = LP_PARPORT_UNSPEC };
@@ -816,6 +837,38 @@ static int lp_register(int nr, struct parport *port)
}
#endif
+#ifdef CONFIG_PPS_CLIENT_LP
+ port->pps_info.owner = THIS_MODULE;
+ port->pps_info.dev = port->dev;
+ snprintf(port->pps_info.path, PPS_MAX_NAME_LEN, "/dev/lp%d", nr);
+
+ /* No PPS support if lp port has no IRQ line */
+ if (port->irq != PARPORT_IRQ_NONE) {
+ strncpy(port->pps_info.name, port->name, PPS_MAX_NAME_LEN);
+
+ port->pps_info.mode = PPS_CAPTUREASSERT | PPS_OFFSETASSERT | \
+ PPS_ECHOASSERT | \
+ PPS_CANWAIT | PPS_TSFMT_TSPEC;
+
+ port->pps_info.echo = lp_pps_echo;
+
+ port->pps_source = pps_register_source(&(port->pps_info),
+ PPS_CAPTUREASSERT | PPS_OFFSETASSERT);
+ if (port->pps_source < 0)
+ dev_err(port->dev,
+ "cannot register PPS source \"%s\"\n",
+ port->pps_info.path);
+ else
+ dev_info(port->dev, "PPS source #%d \"%s\" added\n",
+ port->pps_source, port->pps_info.path);
+ } else {
+ port->pps_source = -1;
+ dev_err(port->dev, "PPS support disabled because port \"%s\" "
+ "is in polling mode\n",
+ port->pps_info.path);
+ }
+#endif
+
return 0;
}
@@ -858,6 +911,14 @@ static void lp_detach (struct parport *port)
console_registered = NULL;
}
#endif /* CONFIG_LP_CONSOLE */
+
+#ifdef CONFIG_PPS_CLIENT_LP
+ if (port->pps_source >= 0) {
+ pps_unregister_source(port->pps_source);
+ dev_dbg(port->dev, "PPS source #%d \"%s\" removed\n",
+ port->pps_source, port->pps_info.path);
+ }
+#endif
}
static struct parport_driver lp_driver = {
diff --git a/drivers/pps/clients/Kconfig b/drivers/pps/clients/Kconfig
index 517c338..09ba5c3 100644
--- a/drivers/pps/clients/Kconfig
+++ b/drivers/pps/clients/Kconfig
@@ -25,4 +25,14 @@ config PPS_CLIENT_UART
If you say yes here you get support for a PPS source connected
with the CD (Carrier Detect) pin of your serial port.
+comment "Parallel printer support (forced off)"
+ depends on !( PRINTER != n && !(PPS = m && PRINTER = y))
+
+config PPS_CLIENT_LP
+ bool "Parallel printer support"
+ depends on PRINTER != n && !(PPS = m && PRINTER = y)
+ help
+ If you say yes here you get support for a PPS source connected
+ with the interrupt pin of your parallel port.
+
endif
diff --git a/include/linux/parport.h b/include/linux/parport.h
index d1ad546..501a9dc 100644
--- a/include/linux/parport.h
+++ b/include/linux/parport.h
@@ -100,6 +100,7 @@ typedef enum {
#include <linux/proc_fs.h>
#include <linux/spinlock.h>
#include <linux/wait.h>
+#include <linux/pps.h>
#include <linux/irqreturn.h>
#include <asm/system.h>
#include <asm/ptrace.h>
@@ -328,6 +329,11 @@ struct parport {
struct list_head full_list;
struct parport *slaves[3];
+
+#ifdef CONFIG_PPS_CLIENT_LP
+ struct pps_source_info pps_info;
+ int pps_source; /* PPS source ID */
+#endif
};
#define DEFAULT_SPIN_TIME 500 /* us */
@@ -516,6 +522,12 @@ extern int parport_daisy_select (struct parport *port, int daisy, int mode);
/* Lowlevel drivers _can_ call this support function to handle irqs. */
static inline void parport_generic_irq(struct parport *port)
{
+#ifdef CONFIG_PPS_CLIENT_LP
+ pps_event(port->pps_source, PPS_CAPTUREASSERT, port);
+ dev_dbg(port->dev, "PPS assert at %lu on source #%d\n",
+ jiffies, port->pps_source);
+#endif
+
parport_ieee1284_interrupt (port);
read_lock(&port->cad_lock);
if (port->cad && port->cad->irq_func)
--
1.5.2.5
This patch adds into the PPS's documentation directory a possible
implementation of the PPS API (RFC 2783) by using the LinuxPPS's char
devices.
This file is not just an example but it can be used into real
systems. :)
Signed-off-by: Rodolfo Giometti <[email protected]>
---
Documentation/pps/timepps.h | 195 +++++++++++++++++++++++++++++++++++++++++++
1 files changed, 195 insertions(+), 0 deletions(-)
create mode 100644 Documentation/pps/timepps.h
diff --git a/Documentation/pps/timepps.h b/Documentation/pps/timepps.h
new file mode 100644
index 0000000..2372949
--- /dev/null
+++ b/Documentation/pps/timepps.h
@@ -0,0 +1,195 @@
+/*
+ * timepps.h -- PPS API main header
+ *
+ * Copyright (C) 2005-2007 Rodolfo Giometti <[email protected]>
+ *
+ * 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 _SYS_TIMEPPS_H_
+#define _SYS_TIMEPPS_H_
+
+#include <sys/syscall.h>
+#include <unistd.h>
+#include <errno.h>
+#include <linux/pps.h>
+
+#define LINUXPPS 1 /* signal we are using LinuxPPS */
+
+/*
+ * New data structures
+ */
+
+struct ntp_fp {
+ unsigned int integral;
+ unsigned int fractional;
+};
+
+union pps_timeu {
+ struct timespec tspec;
+ struct ntp_fp ntpfp;
+ unsigned long longpad[3];
+};
+
+struct pps_info {
+ unsigned long assert_sequence; /* seq. num. of assert event */
+ unsigned long clear_sequence; /* seq. num. of clear event */
+ union pps_timeu assert_tu; /* time of assert event */
+ union pps_timeu clear_tu; /* time of clear event */
+ int current_mode; /* current mode bits */
+};
+
+struct pps_params {
+ int api_version; /* API version # */
+ int mode; /* mode bits */
+ union pps_timeu assert_off_tu; /* offset compensation for assert */
+ union pps_timeu clear_off_tu; /* offset compensation for clear */
+};
+
+typedef int pps_handle_t; /* represents a PPS source */
+typedef unsigned long pps_seq_t; /* sequence number */
+typedef struct ntp_fp ntp_fp_t; /* NTP-compatible time stamp */
+typedef union pps_timeu pps_timeu_t; /* generic data type for time stamps */
+typedef struct pps_info pps_info_t;
+typedef struct pps_params pps_params_t;
+
+#define assert_timestamp assert_tu.tspec
+#define clear_timestamp clear_tu.tspec
+
+#define assert_timestamp_ntpfp assert_tu.ntpfp
+#define clear_timestamp_ntpfp clear_tu.ntpfp
+
+#define assert_offset assert_off_tu.tspec
+#define clear_offset clear_off_tu.tspec
+
+#define assert_offset_ntpfp assert_off_tu.ntpfp
+#define clear_offset_ntpfp clear_off_tu.ntpfp
+
+/*
+ * The PPS API
+ */
+
+static __inline int time_pps_create(int source, pps_handle_t *handle)
+{
+ int ret;
+
+ if (!handle) {
+ errno = EINVAL;
+ return -1;
+ }
+
+ /* First we check if current device is a PPS valid PPS one...
+ */
+ ret = ioctl(source, PPS_CHECK);
+ if (ret) {
+ errno = EOPNOTSUPP;
+ return -1;
+ }
+
+ /* ... then since in LinuxPPS there are no differences between a
+ * "PPS source" and a "PPS handle", we simply return the same value.
+ */
+ *handle = source;
+
+ return 0;
+}
+
+static __inline int time_pps_destroy(pps_handle_t handle)
+{
+ return close(handle);
+}
+
+static __inline int time_pps_getparams(pps_handle_t handle,
+ pps_params_t *ppsparams)
+{
+ int ret;
+ struct pps_kparams __ppsparams;
+
+ ret = ioctl(handle, PPS_GETPARAMS, &__ppsparams);
+
+ ppsparams->api_version = __ppsparams.api_version;
+ ppsparams->mode = __ppsparams.mode;
+ ppsparams->assert_off_tu.tspec.tv_sec = __ppsparams.assert_off_tu.sec;
+ ppsparams->assert_off_tu.tspec.tv_nsec = __ppsparams.assert_off_tu.nsec;
+ ppsparams->clear_off_tu.tspec.tv_sec = __ppsparams.clear_off_tu.sec;
+ ppsparams->clear_off_tu.tspec.tv_nsec = __ppsparams.clear_off_tu.nsec;
+
+ return ret;
+}
+
+static __inline int time_pps_setparams(pps_handle_t handle,
+ const pps_params_t *ppsparams)
+{
+ struct pps_kparams __ppsparams;
+
+ __ppsparams.api_version = ppsparams->api_version;
+ __ppsparams.mode = ppsparams->mode;
+ __ppsparams.assert_off_tu.sec = ppsparams->assert_off_tu.tspec.tv_sec;
+ __ppsparams.assert_off_tu.nsec = ppsparams->assert_off_tu.tspec.tv_nsec;
+ __ppsparams.clear_off_tu.sec = ppsparams->clear_off_tu.tspec.tv_sec;
+ __ppsparams.clear_off_tu.nsec = ppsparams->clear_off_tu.tspec.tv_nsec;
+
+ return ioctl(handle, PPS_SETPARAMS, &__ppsparams);
+}
+
+/* Get capabilities for handle */
+static __inline int time_pps_getcap(pps_handle_t handle, int *mode)
+{
+ return ioctl(handle, PPS_GETCAP, mode);
+}
+
+static __inline int time_pps_fetch(pps_handle_t handle, const int tsformat,
+ pps_info_t *ppsinfobuf,
+ const struct timespec *timeout)
+{
+ struct pps_fdata __fdata;
+ int ret;
+
+ /* Sanity checks */
+ if (tsformat != PPS_TSFMT_TSPEC) {
+ errno = EINVAL;
+ return -1;
+ }
+
+ if (timeout) {
+ __fdata.timeout.sec = timeout->tv_sec;
+ __fdata.timeout.nsec = timeout->tv_nsec;
+ __fdata.timeout.flags = ~PPS_TIME_INVALID;
+ } else
+ __fdata.timeout.flags = PPS_TIME_INVALID;
+
+ ret = ioctl(handle, PPS_FETCH, &__fdata);
+
+ ppsinfobuf->assert_sequence = __fdata.info.assert_sequence;
+ ppsinfobuf->clear_sequence = __fdata.info.clear_sequence;
+ ppsinfobuf->assert_tu.tspec.tv_sec = __fdata.info.assert_tu.sec;
+ ppsinfobuf->assert_tu.tspec.tv_nsec = __fdata.info.assert_tu.nsec;
+ ppsinfobuf->clear_tu.tspec.tv_sec = __fdata.info.clear_tu.sec;
+ ppsinfobuf->clear_tu.tspec.tv_nsec = __fdata.info.clear_tu.nsec;
+ ppsinfobuf->current_mode = __fdata.info.current_mode;
+
+ return ret;
+}
+
+static __inline int time_pps_kcbind(pps_handle_t handle,
+ const int kernel_consumer,
+ const int edge, const int tsformat)
+{
+ /* LinuxPPS doesn't implement kernel consumer feature */
+ errno = EOPNOTSUPP;
+ return -1;
+}
+
+#endif /* _SYS_TIMEPPS_H_ */
--
1.5.2.5
Signed-off-by: Rodolfo Giometti <[email protected]>
---
Documentation/pps/Makefile | 2 +-
Documentation/pps/ppsctl.c | 62 ++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 63 insertions(+), 1 deletions(-)
create mode 100644 Documentation/pps/ppsctl.c
diff --git a/Documentation/pps/Makefile b/Documentation/pps/Makefile
index af4f9b4..8ef4f47 100644
--- a/Documentation/pps/Makefile
+++ b/Documentation/pps/Makefile
@@ -1,4 +1,4 @@
-TARGETS = ppstest
+TARGETS = ppstest ppsctl
CFLAGS += -Wall -O2 -D_GNU_SOURCE
CFLAGS += -I .
diff --git a/Documentation/pps/ppsctl.c b/Documentation/pps/ppsctl.c
new file mode 100644
index 0000000..83fd08a
--- /dev/null
+++ b/Documentation/pps/ppsctl.c
@@ -0,0 +1,62 @@
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <string.h>
+#include <linux/serial.h>
+
+void usage(char *name)
+{
+ fprintf(stderr, "usage: %s <ttyS> [enable|disable]\n", name);
+
+ exit(EXIT_FAILURE);
+}
+
+int main(int argc, char *argv[])
+{
+ int fd;
+ int ret;
+ struct serial_struct ss;
+
+ if (argc < 2)
+ usage(argv[0]);
+
+ fd = open(argv[1], O_RDWR);
+ if (fd < 0) {
+ perror("open");
+ exit(EXIT_FAILURE);
+ }
+
+ ret = ioctl(fd, TIOCGSERIAL, &ss);
+ if (ret < 0) {
+ perror("ioctl(TIOCGSERIAL)");
+ exit(EXIT_FAILURE);
+ }
+
+ if (argc < 3) { /* just read PPS status */
+ printf("PPS is %sabled\n",
+ ss.flags & ASYNC_HARDPPS_CD ? "en" : "dis");
+ exit(EXIT_SUCCESS);
+ }
+
+ if (argv[2][0] == 'e' || argv[2][0] == '1')
+ ss.flags |= ASYNC_HARDPPS_CD;
+ else if (argv[2][0] == 'd' || argv[2][0] == '0')
+ ss.flags &= ~ASYNC_HARDPPS_CD;
+ else {
+ fprintf(stderr, "invalid state argument \"%s\"\n", argv[2]);
+ exit(EXIT_FAILURE);
+ }
+
+ ret = ioctl(fd, TIOCSSERIAL, &ss);
+ if (ret < 0) {
+ perror("ioctl(TIOCSSERIAL)");
+ exit(EXIT_FAILURE);
+ }
+
+ return 0;
+}
--
1.5.2.5
Each PPS source can be registered/deregistered into the system by
using special modules called "clients". They simply define the PPS
sources' attributes and implement the time signal registartion
mechanism.
This patch adds a special directory for such clients and adds a dummy
client that can be useful to test system integrity on real systems.
Signed-off-by: Rodolfo Giometti <[email protected]>
---
drivers/pps/Kconfig | 2 +
drivers/pps/Makefile | 1 +
drivers/pps/clients/Kconfig | 18 +++++++
drivers/pps/clients/Makefile | 9 +++
drivers/pps/clients/ktimer.c | 114 ++++++++++++++++++++++++++++++++++++++++++
5 files changed, 144 insertions(+), 0 deletions(-)
create mode 100644 drivers/pps/clients/Kconfig
create mode 100644 drivers/pps/clients/Makefile
create mode 100644 drivers/pps/clients/ktimer.c
diff --git a/drivers/pps/Kconfig b/drivers/pps/Kconfig
index dce4a1f..0c82285 100644
--- a/drivers/pps/Kconfig
+++ b/drivers/pps/Kconfig
@@ -29,4 +29,6 @@ config PPS_DEBUG
messages to the system log. Select this if you are having a
problem with PPS support and want to see more of what is going on.
+source drivers/pps/clients/Kconfig
+
endmenu
diff --git a/drivers/pps/Makefile b/drivers/pps/Makefile
index 5a9a51b..d8ec308 100644
--- a/drivers/pps/Makefile
+++ b/drivers/pps/Makefile
@@ -4,6 +4,7 @@
pps_core-objs += pps.o kapi.o sysfs.o
obj-$(CONFIG_PPS) += pps_core.o
+obj-y += clients/
ifeq ($(CONFIG_PPS_DEBUG),y)
EXTRA_CFLAGS += -DDEBUG
diff --git a/drivers/pps/clients/Kconfig b/drivers/pps/clients/Kconfig
new file mode 100644
index 0000000..60b83be
--- /dev/null
+++ b/drivers/pps/clients/Kconfig
@@ -0,0 +1,18 @@
+#
+# PPS clients configuration
+#
+
+if PPS
+
+comment "PPS clients support"
+
+config PPS_CLIENT_KTIMER
+ tristate "Kernel timer client (Testing client, use for debug)"
+ help
+ If you say yes here you get support for a PPS debugging client
+ which uses a kernel timer to generate the PPS signal.
+
+ This driver can also be built as a module. If so, the module
+ will be called ktimer.ko.
+
+endif
diff --git a/drivers/pps/clients/Makefile b/drivers/pps/clients/Makefile
new file mode 100644
index 0000000..f3c1e39
--- /dev/null
+++ b/drivers/pps/clients/Makefile
@@ -0,0 +1,9 @@
+#
+# Makefile for PPS clients.
+#
+
+obj-$(CONFIG_PPS_CLIENT_KTIMER) += ktimer.o
+
+ifeq ($(CONFIG_PPS_DEBUG),y)
+EXTRA_CFLAGS += -DDEBUG
+endif
diff --git a/drivers/pps/clients/ktimer.c b/drivers/pps/clients/ktimer.c
new file mode 100644
index 0000000..5845188
--- /dev/null
+++ b/drivers/pps/clients/ktimer.c
@@ -0,0 +1,114 @@
+/*
+ * ktimer.c -- kernel timer test client
+ *
+ *
+ * Copyright (C) 2005-2006 Rodolfo Giometti <[email protected]>
+ *
+ * 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/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/time.h>
+#include <linux/timer.h>
+
+#include <linux/pps.h>
+
+/*
+ * Global variables
+ */
+
+static int source;
+static struct timer_list ktimer;
+
+/*
+ * The kernel timer
+ */
+
+static void pps_ktimer_event(unsigned long ptr)
+{
+ pr_info("PPS event at %lu\n", jiffies);
+
+ pps_event(source, PPS_CAPTUREASSERT, NULL);
+
+ mod_timer(&ktimer, jiffies + HZ);
+}
+
+/*
+ * The echo function
+ */
+
+static void pps_ktimer_echo(int source, int event, void *data)
+{
+ pr_info("echo %s %s for source %d\n",
+ event & PPS_CAPTUREASSERT ? "assert" : "",
+ event & PPS_CAPTURECLEAR ? "clear" : "",
+ source);
+}
+
+/*
+ * The PPS info struct
+ */
+
+static struct pps_source_info pps_ktimer_info = {
+ .name = "ktimer",
+ .path = "",
+ .mode = PPS_CAPTUREASSERT | PPS_OFFSETASSERT | \
+ PPS_ECHOASSERT | \
+ PPS_CANWAIT | PPS_TSFMT_TSPEC,
+ .echo = pps_ktimer_echo,
+ .owner = THIS_MODULE,
+};
+
+/*
+ * Module staff
+ */
+
+static void __exit pps_ktimer_exit(void)
+{
+ del_timer_sync(&ktimer);
+ pps_unregister_source(source);
+
+ pr_info("ktimer PPS source unregistered\n");
+}
+
+static int __init pps_ktimer_init(void)
+{
+ int ret;
+
+ ret = pps_register_source(&pps_ktimer_info,
+ PPS_CAPTUREASSERT | PPS_OFFSETASSERT);
+ if (ret < 0) {
+ printk(KERN_ERR "cannot register ktimer source\n");
+ return ret;
+ }
+ source = ret;
+
+ setup_timer(&ktimer, pps_ktimer_event, 0);
+ mod_timer(&ktimer, jiffies + HZ);
+
+ pr_info("ktimer PPS source registered at %d\n", source);
+
+ return 0;
+}
+
+module_init(pps_ktimer_init);
+module_exit(pps_ktimer_exit);
+
+MODULE_AUTHOR("Rodolfo Giometti <[email protected]>");
+MODULE_DESCRIPTION("dummy PPS source by using a kernel timer (just for debug)");
+MODULE_LICENSE("GPL");
--
1.5.2.5
Signed-off-by: Rodolfo Giometti <[email protected]>
---
Documentation/pps/pps.txt | 170 +++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 170 insertions(+), 0 deletions(-)
create mode 100644 Documentation/pps/pps.txt
diff --git a/Documentation/pps/pps.txt b/Documentation/pps/pps.txt
new file mode 100644
index 0000000..2af58bd
--- /dev/null
+++ b/Documentation/pps/pps.txt
@@ -0,0 +1,170 @@
+
+ PPS - Pulse Per Second
+ ----------------------
+
+(C) Copyright 2007 Rodolfo Giometti <[email protected]>
+
+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.
+
+
+
+Overview
+--------
+
+LinuxPPS provides a programming interface (API) to define into the
+system several PPS sources.
+
+PPS means "pulse per second" and a PPS source is just a device which
+provides a high precision signal each second so that an application
+can use it to adjust system clock time.
+
+A PPS source can be connected to a serial port (usually to the Data
+Carrier Detect pin) or to a parallel port (ACK-pin) or to a special
+CPU's GPIOs (this is the common case in embedded systems) but in each
+case when a new pulse comes the system must apply to it a timestamp
+and record it for the userland.
+
+Common use is the combination of the NTPD as userland program with a
+GPS receiver as PPS source to obtain a wallclock-time with
+sub-millisecond synchronisation to UTC.
+
+
+RFC considerations
+------------------
+
+While implementing a PPS API as RFC 2783 defines and using an embedded
+CPU GPIO-Pin as physical link to the signal, I encountered a deeper
+problem:
+
+ At startup it needs a file descriptor as argument for the function
+ time_pps_create().
+
+This implies that the source has a /dev/... entry. This assumption is
+ok for the serial and parallel port, where you can do something
+useful besides(!) the gathering of timestamps as it is the central
+task for a PPS-API. But this assumption does not work for a single
+purpose GPIO line. In this case even basic file-related functionality
+(like read() and write()) makes no sense at all and should not be a
+precondition for the use of a PPS-API.
+
+The problem can be simply solved if you consider that a PPS source is
+not always connected with a GPS data source.
+
+So your programs should check if the GPS data source (the serial port
+for instance) is a PPS source too, otherwise they should provide the
+possibility to open another device as PPS source.
+
+In LinuxPPS the PPS sources are simply char devices usually mapped
+into files /dev/pps0, /dev/pps1, etc..
+
+
+Coding example
+--------------
+
+To register a PPS source into the kernel you should define a struct
+pps_source_info_s as follow:
+
+ static struct pps_source_info_s pps_ktimer_info = {
+ .name = "ktimer",
+ .path = "",
+ .mode = PPS_CAPTUREASSERT | PPS_OFFSETASSERT | \
+ PPS_ECHOASSERT | \
+ PPS_CANWAIT | PPS_TSFMT_TSPEC,
+ .echo = pps_ktimer_echo,
+ .owner = THIS_MODULE,
+ };
+
+and then calling the function pps_register_source() in your
+intialization routine as follow:
+
+ source = pps_register_source(&pps_ktimer_info,
+ PPS_CAPTUREASSERT | PPS_OFFSETASSERT);
+
+The pps_register_source() prototype is:
+
+ int pps_register_source(struct pps_source_info_s *info, int default_params)
+
+where "info" is a pointer to a structure that describes a particular
+PPS source, "default_params" tells the system what the initial default
+parameters for the device should be (is obvious that these parameters
+must be a subset of ones defined into the struct
+pps_source_info_s which describe the capabilities of the driver).
+
+Once you have registered a new PPS source into the system you can
+signal an assert event (for example in the interrupt handler routine)
+just using:
+
+ pps_event(source, PPS_CAPTUREASSERT, ptr);
+
+The same function may also run the defined echo function
+(pps_ktimer_echo(), passing to it the "ptr" pointer) if the user
+asked for that... etc..
+
+Please see the file drivers/pps/clients/ktimer.c for an example code.
+
+
+SYSFS support
+-------------
+
+If the SYSFS filesystem is enabled in the kernel it provides a new class:
+
+ $ ls /sys/class/pps/
+ pps0/ pps1/ pps2/
+
+Every directory is the ID of a PPS sources defined into the system and
+inside you find several files:
+
+ $ ls /sys/class/pps/pps0/
+ assert clear echo mode name path subsystem@ uevent
+
+Inside each "assert" and "clear" file you can find the timestamp and a
+sequence number:
+
+ $ cat /sys/class/pps/pps0/assert
+ 1170026870.983207967#8
+
+Where before the "#" is the timestamp in seconds and after it is the
+sequence number. Other files are:
+
+* echo: reports if the PPS source has an echo function or not;
+
+* mode: reports available PPS functioning modes;
+
+* name: reports the PPS source's name;
+
+* path: reports the PPS source's device path, that is the device the
+ PPS source is connected to (if it exists).
+
+
+Testing the PPS support
+-----------------------
+
+In order to test the PPS support even without specific hardware you can use
+the ktimer driver (see the client subsection in the PPS configuration menu)
+and the userland tools provided into Documentaion/pps/ directory.
+
+Once you have enabled the compilation of ktimer just modprobe it (if
+not statically compiled):
+
+ # modprobe ktimer
+
+and the run ppstest as follow:
+
+ $ ./ppstest /dev/pps0
+ trying PPS source "/dev/pps1"
+ found PPS source "/dev/pps1"
+ ok, found 1 source(s), now start fetching data...
+ source 0 - assert 1186592699.388832443, sequence: 364 - clear 0.000000000, sequence: 0
+ source 0 - assert 1186592700.388931295, sequence: 365 - clear 0.000000000, sequence: 0
+ source 0 - assert 1186592701.389032765, sequence: 366 - clear 0.000000000, sequence: 0
+
+Please, note that to compile userland programs you need the file timepps.h
+(see Documentation/pps/).
--
1.5.2.5
Adds support for the PPS sources connected with the CD (Carrier
Detect) pin of a serial port.
Signed-off-by: Rodolfo Giometti <[email protected]>
---
drivers/pps/clients/Kconfig | 10 ++++++
drivers/serial/8250.c | 2 +
drivers/serial/serial_core.c | 71 +++++++++++++++++++++++++++++++++++++++++-
include/linux/serial_core.h | 30 ++++++++++++++---
4 files changed, 106 insertions(+), 7 deletions(-)
diff --git a/drivers/pps/clients/Kconfig b/drivers/pps/clients/Kconfig
index 60b83be..517c338 100644
--- a/drivers/pps/clients/Kconfig
+++ b/drivers/pps/clients/Kconfig
@@ -15,4 +15,14 @@ config PPS_CLIENT_KTIMER
This driver can also be built as a module. If so, the module
will be called ktimer.ko.
+comment "UART serial support (forced off)"
+ depends on ! (SERIAL_CORE != n && !(PPS = m && SERIAL_CORE = y))
+
+config PPS_CLIENT_UART
+ bool "UART serial support"
+ depends on SERIAL_CORE != n && !(PPS = m && SERIAL_CORE = y)
+ help
+ If you say yes here you get support for a PPS source connected
+ with the CD (Carrier Detect) pin of your serial port.
+
endif
diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index f94109c..a5e83f8 100644
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -2118,6 +2118,8 @@ serial8250_set_termios(struct uart_port *port, struct ktermios *termios,
up->ier |= UART_IER_MSI;
if (up->capabilities & UART_CAP_UUE)
up->ier |= UART_IER_UUE | UART_IER_RTOIE;
+ if (up->port.flags & UPF_HARDPPS_CD)
+ up->ier |= UART_IER_MSI; /* enable interrupts */
serial_out(up, UART_IER, up->ier);
diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c
index 3bb5d24..ff6cdac 100644
--- a/drivers/serial/serial_core.c
+++ b/drivers/serial/serial_core.c
@@ -33,6 +33,7 @@
#include <linux/serial.h> /* for serial_state and serial_icounter_struct */
#include <linux/delay.h>
#include <linux/mutex.h>
+#include <linux/pps.h>
#include <asm/irq.h>
#include <asm/uaccess.h>
@@ -633,6 +634,54 @@ static int uart_get_info(struct uart_state *state,
return 0;
}
+#ifdef CONFIG_PPS_CLIENT_UART
+
+static int
+uart_register_pps_port(struct uart_state *state, struct uart_port *port)
+{
+ struct tty_driver *drv = port->info->tty->driver;
+ int ret;
+
+ state->pps_info.owner = THIS_MODULE;
+ state->pps_info.dev = port->dev;
+ snprintf(state->pps_info.name, PPS_MAX_NAME_LEN, "%s%d",
+ drv->driver_name, port->line);
+ snprintf(state->pps_info.path, PPS_MAX_NAME_LEN, "/dev/%s%d",
+ drv->name, port->line);
+
+ state->pps_info.mode = PPS_CAPTUREBOTH | \
+ PPS_OFFSETASSERT | PPS_OFFSETCLEAR | \
+ PPS_CANWAIT | PPS_TSFMT_TSPEC;
+
+ ret = pps_register_source(&state->pps_info, PPS_CAPTUREBOTH | \
+ PPS_OFFSETASSERT | PPS_OFFSETCLEAR);
+ if (ret < 0) {
+ dev_err(port->dev, "cannot register PPS source \"%s\"\n",
+ state->pps_info.path);
+ return ret;
+ }
+ port->pps_source = ret;
+ dev_dbg(port->dev, "PPS source #%d \"%s\" added\n",
+ port->pps_source, state->pps_info.path);
+
+ return 0;
+}
+
+static void
+uart_unregister_pps_port(struct uart_state *state, struct uart_port *port)
+{
+ pps_unregister_source(port->pps_source);
+ dev_dbg(port->dev, "PPS source #%d \"%s\" removed\n",
+ port->pps_source, state->pps_info.path);
+}
+
+#else
+
+#define uart_register_pps_port(state, port) do { } while (0)
+#define uart_unregister_pps_port(state, port) do { } while (0)
+
+#endif /* CONFIG_PPS_CLIENT_UART */
+
static int uart_set_info(struct uart_state *state,
struct serial_struct __user *newinfo)
{
@@ -807,11 +856,19 @@ static int uart_set_info(struct uart_state *state,
(port->flags & UPF_LOW_LATENCY) ? 1 : 0;
check_and_exit:
+ /* PPS support enabled/disabled? */
+ if ((old_flags & UPF_HARDPPS_CD) != (new_flags & UPF_HARDPPS_CD)) {
+ if (new_flags & UPF_HARDPPS_CD)
+ uart_register_pps_port(state, port);
+ else
+ uart_unregister_pps_port(state, port);
+ }
+
retval = 0;
if (port->type == PORT_UNKNOWN)
goto exit;
if (state->info->flags & UIF_INITIALIZED) {
- if (((old_flags ^ port->flags) & UPF_SPD_MASK) ||
+ if (((old_flags ^ port->flags) & (UPF_SPD_MASK|UPF_HARDPPS_CD)) ||
old_custom_divisor != port->custom_divisor) {
/*
* If they're setting up a custom divisor or speed,
@@ -2140,6 +2197,12 @@ uart_configure_port(struct uart_driver *drv, struct uart_state *state,
port->ops->config_port(port, flags);
}
+ /*
+ * Add the PPS support for the current port.
+ */
+ if (port->flags & UPF_HARDPPS_CD)
+ uart_register_pps_port(state, port);
+
if (port->type != PORT_UNKNOWN) {
unsigned long flags;
@@ -2396,6 +2459,12 @@ int uart_remove_one_port(struct uart_driver *drv, struct uart_port *port)
mutex_unlock(&state->mutex);
/*
+ * Remove PPS support from the current port.
+ */
+ if (port->flags & UPF_HARDPPS_CD)
+ uart_unregister_pps_port(state, port);
+
+ /*
* Remove the devices from the tty layer
*/
tty_unregister_device(drv->tty_driver, port->line);
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 9963f81..c8e4d92 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -160,6 +160,7 @@
#include <linux/tty.h>
#include <linux/mutex.h>
#include <linux/sysrq.h>
+#include <linux/pps.h>
struct uart_port;
struct uart_info;
@@ -239,6 +240,9 @@ struct uart_port {
unsigned char regshift; /* reg offset shift */
unsigned char iotype; /* io access style */
unsigned char unused1;
+#ifdef CONFIG_PPS_CLIENT_UART
+ int pps_source; /* PPS source ID */
+#endif
#define UPIO_PORT (0)
#define UPIO_HUB6 (1)
@@ -283,7 +287,8 @@ struct uart_port {
#define UPF_IOREMAP ((__force upf_t) (1 << 31))
#define UPF_CHANGE_MASK ((__force upf_t) (0x17fff))
-#define UPF_USR_MASK ((__force upf_t) (UPF_SPD_MASK|UPF_LOW_LATENCY))
+#define UPF_USR_MASK ((__force upf_t) (UPF_SPD_MASK|UPF_LOW_LATENCY\
+ |UPF_HARDPPS_CD))
unsigned int mctrl; /* current modem ctrl settings */
unsigned int timeout; /* character-based timeout */
@@ -316,6 +321,10 @@ struct uart_state {
struct uart_info *info;
struct uart_port *port;
+#ifdef CONFIG_PPS_CLIENT_UART
+ struct pps_source_info pps_info;
+#endif
+
struct mutex mutex;
};
@@ -480,13 +489,22 @@ uart_handle_dcd_change(struct uart_port *port, unsigned int status)
{
struct uart_info *info = port->info;
- port->icount.dcd++;
-
-#ifdef CONFIG_HARD_PPS
- if ((port->flags & UPF_HARDPPS_CD) && status)
- hardpps();
+#ifdef CONFIG_PPS_CLIENT_UART
+ if (port->flags & UPF_HARDPPS_CD) {
+ if (status) {
+ pps_event(port->pps_source, PPS_CAPTUREASSERT, port);
+ dev_dbg(port->dev, "PPS assert at %lu on source #%d\n",
+ jiffies, port->pps_source);
+ } else {
+ pps_event(port->pps_source, PPS_CAPTURECLEAR, port);
+ dev_dbg(port->dev, "PPS clear at %lu on source #%d\n",
+ jiffies, port->pps_source);
+ }
+ }
#endif
+ port->icount.dcd++;
+
if (info->flags & UIF_CHECK_CD) {
if (status)
wake_up_interruptible(&info->open_wait);
--
1.5.2.5
This patch adds the kernel side of the PPS support currently named
"LinuxPPS".
PPS means "pulse per second" and a PPS source is just a device which
provides a high precision signal each second so that an application
can use it to adjust system clock time.
Common use is the combination of the NTPD as userland program with a
GPS receiver as PPS source to obtain a wallclock-time with
sub-millisecond synchronisation to UTC.
To obtain this goal the userland programs shoud use the PPS API
specification (RFC 2783 - Pulse-Per-Second API for UNIX-like Operating
Systems, Version 1.0) which in part is implemented by this patch. It
provides a set of chars devices, one per PPS source, which can be used
to get the time signal. The RFC's functions can be implemented by
accessing to these char devices.
Signed-off-by: Rodolfo Giometti <[email protected]>
---
MAINTAINERS | 7 +
drivers/Kconfig | 2 +
drivers/Makefile | 1 +
drivers/pps/Kconfig | 32 +++++
drivers/pps/Makefile | 10 ++
drivers/pps/kapi.c | 272 +++++++++++++++++++++++++++++++++++++++
drivers/pps/pps.c | 342 ++++++++++++++++++++++++++++++++++++++++++++++++++
drivers/pps/sysfs.c | 142 +++++++++++++++++++++
include/linux/Kbuild | 1 +
include/linux/pps.h | 204 ++++++++++++++++++++++++++++++
10 files changed, 1013 insertions(+), 0 deletions(-)
create mode 100644 drivers/pps/Kconfig
create mode 100644 drivers/pps/Makefile
create mode 100644 drivers/pps/kapi.c
create mode 100644 drivers/pps/pps.c
create mode 100644 drivers/pps/sysfs.c
create mode 100644 include/linux/pps.h
diff --git a/MAINTAINERS b/MAINTAINERS
index 58b1603..c1cd5c2 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3096,6 +3096,13 @@ P: James Chapman
M: [email protected]
S: Maintained
+PPS SUPPORT
+P: Rodolfo Giometti
+M: [email protected]
+W: http://wiki.enneenne.com/index.php/LinuxPPS_support
+L: [email protected]
+S: Maintained
+
PREEMPTIBLE KERNEL
P: Robert Love
M: [email protected]
diff --git a/drivers/Kconfig b/drivers/Kconfig
index 08d4ae2..2c656c8 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -52,6 +52,8 @@ source "drivers/i2c/Kconfig"
source "drivers/spi/Kconfig"
+source "drivers/pps/Kconfig"
+
source "drivers/w1/Kconfig"
source "drivers/power/Kconfig"
diff --git a/drivers/Makefile b/drivers/Makefile
index 0ee9a8a..da8fee3 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -61,6 +61,7 @@ obj-$(CONFIG_INPUT) += input/
obj-$(CONFIG_I2O) += message/
obj-$(CONFIG_RTC_LIB) += rtc/
obj-y += i2c/
+obj-$(CONFIG_PPS) += pps/
obj-$(CONFIG_W1) += w1/
obj-$(CONFIG_POWER_SUPPLY) += power/
obj-$(CONFIG_HWMON) += hwmon/
diff --git a/drivers/pps/Kconfig b/drivers/pps/Kconfig
new file mode 100644
index 0000000..dce4a1f
--- /dev/null
+++ b/drivers/pps/Kconfig
@@ -0,0 +1,32 @@
+#
+# PPS support configuration
+#
+
+menu "PPS support"
+
+config PPS
+ tristate "PPS support"
+ depends on EXPERIMENTAL
+ ---help---
+ PPS (Pulse Per Second) is a special pulse provided by some GPS
+ antennae. Userland can use it to get an high time reference.
+
+ Some antennae's PPS signals are connected with the CD (Carrier
+ Detect) pin of the serial line they use to communicate with the
+ host. In this case use the SERIAL_LINE client support.
+
+ Some antennae's PPS signals are connected with some special host
+ inputs so you have to enable the corresponding client support.
+
+ To compile this driver as a module, choose M here: the module
+ will be called pps_core.ko.
+
+config PPS_DEBUG
+ bool "PPS debugging messages"
+ depends on PPS
+ help
+ Say Y here if you want the PPS support to produce a bunch of debug
+ messages to the system log. Select this if you are having a
+ problem with PPS support and want to see more of what is going on.
+
+endmenu
diff --git a/drivers/pps/Makefile b/drivers/pps/Makefile
new file mode 100644
index 0000000..5a9a51b
--- /dev/null
+++ b/drivers/pps/Makefile
@@ -0,0 +1,10 @@
+#
+# Makefile for the PPS core.
+#
+
+pps_core-objs += pps.o kapi.o sysfs.o
+obj-$(CONFIG_PPS) += pps_core.o
+
+ifeq ($(CONFIG_PPS_DEBUG),y)
+EXTRA_CFLAGS += -DDEBUG
+endif
diff --git a/drivers/pps/kapi.c b/drivers/pps/kapi.c
new file mode 100644
index 0000000..c127e66
--- /dev/null
+++ b/drivers/pps/kapi.c
@@ -0,0 +1,272 @@
+/*
+ * kapi.c -- kernel API
+ *
+ *
+ * Copyright (C) 2005-2007 Rodolfo Giometti <[email protected]>
+ *
+ * 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/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/time.h>
+#include <linux/spinlock.h>
+#include <linux/idr.h>
+#include <linux/fs.h>
+#include <linux/pps.h>
+
+/*
+ * Global variables
+ */
+
+DEFINE_SPINLOCK(idr_lock);
+DEFINE_IDR(pps_idr);
+
+/*
+ * Local functions
+ */
+
+static void pps_add_offset(struct pps_ktime *ts, struct pps_ktime *offset)
+{
+ ts->nsec += offset->nsec;
+ while (ts->nsec >= NSEC_PER_SEC) {
+ ts->nsec -= NSEC_PER_SEC;
+ ts->sec++;
+ }
+ while (ts->nsec < 0) {
+ ts->nsec += NSEC_PER_SEC;
+ ts->sec--;
+ }
+ ts->sec += offset->sec;
+}
+
+/*
+ * Exported functions
+ */
+
+int pps_register_source(struct pps_source_info *info, int default_params)
+{
+ struct pps_device *pps;
+ int id;
+ int err;
+
+ /* Sanity checks */
+ if ((info->mode & default_params) != default_params) {
+ printk(KERN_ERR "pps: %s: unsupported default parameters\n",
+ info->name);
+ err = -EINVAL;
+ goto pps_register_source_exit;
+ }
+ if ((info->mode & (PPS_ECHOASSERT | PPS_ECHOCLEAR)) != 0 &&
+ info->echo == NULL) {
+ printk(KERN_ERR "pps: %s: echo function is not defined\n",
+ info->name);
+ err = -EINVAL;
+ goto pps_register_source_exit;
+ }
+ if ((info->mode & (PPS_TSFMT_TSPEC | PPS_TSFMT_NTPFP)) == 0) {
+ printk(KERN_ERR "pps: %s: unspecified time format\n",
+ info->name);
+ err = -EINVAL;
+ goto pps_register_source_exit;
+ }
+
+ /* Allocate memory for the new PPS source struct */
+ pps = kzalloc(sizeof(struct pps_device), GFP_KERNEL);
+ if (pps == NULL) {
+ err = -ENOMEM;
+ goto pps_register_source_exit;
+ }
+
+ /* Get new ID for the new PPS source */
+ if (idr_pre_get(&pps_idr, GFP_KERNEL) == 0) {
+ err = -ENOMEM;
+ goto kfree_pps;
+ }
+
+ spin_lock_irq(&idr_lock);
+ err = idr_get_new(&pps_idr, pps, &id);
+ spin_unlock_irq(&idr_lock);
+
+ if (err < 0)
+ goto kfree_pps;
+
+ id = id & MAX_ID_MASK;
+ if (id >= PPS_MAX_SOURCES) {
+ printk(KERN_ERR "pps: %s: too many PPS sources in the system\n",
+ info->name);
+ err = -EBUSY;
+ goto free_idr;
+ }
+
+ pps->id = id;
+ pps->params.api_version = PPS_API_VERS;
+ pps->params.mode = default_params;
+ pps->info = *info;
+
+ init_waitqueue_head(&pps->queue);
+ spin_lock_init(&pps->lock);
+ atomic_set(&pps->usage, 0);
+ init_waitqueue_head(&pps->usage_queue);
+
+ /* Create the char device */
+ err = pps_register_cdev(pps);
+ if (err < 0) {
+ printk(KERN_ERR "pps: %s: unable to create char device\n",
+ info->name);
+ goto free_idr;
+ }
+
+ /* Create the sysfs entry */
+ err = pps_sysfs_create_source_entry(pps);
+ if (err < 0) {
+ printk(KERN_ERR "pps: %s: unable to create sysfs entries\n",
+ info->name);
+ goto unregister_cdev;
+ }
+
+ pr_info("new PPS source %s at ID %d\n", info->name, id);
+
+ return id;
+
+unregister_cdev:
+ pps_unregister_cdev(pps);
+
+free_idr:
+ spin_lock_irq(&idr_lock);
+ idr_remove(&pps_idr, id);
+ spin_unlock_irq(&idr_lock);
+
+kfree_pps:
+ kfree(pps);
+
+pps_register_source_exit:
+ printk(KERN_ERR "pps: %s: unable to register source\n", info->name);
+
+ return err;
+}
+EXPORT_SYMBOL(pps_register_source);
+
+void pps_unregister_source(int source)
+{
+ struct pps_device *pps;
+
+ spin_lock_irq(&idr_lock);
+ pps = idr_find(&pps_idr, source);
+
+ if (!pps) {
+ spin_unlock_irq(&idr_lock);
+ return;
+ }
+
+ /* This should be done first in order to deny IRQ handlers
+ * to access PPS structs
+ */
+
+ idr_remove(&pps_idr, pps->id);
+ spin_unlock_irq(&idr_lock);
+
+ wait_event(pps->usage_queue, atomic_read(&pps->usage) == 0);
+
+ pps_sysfs_remove_source_entry(pps);
+ pps_unregister_cdev(pps);
+ kfree(pps);
+}
+EXPORT_SYMBOL(pps_unregister_source);
+
+void pps_event(int source, int event, void *data)
+{
+ struct pps_device *pps;
+ struct timespec __ts;
+ struct pps_ktime ts;
+ unsigned long flags;
+
+ /* First of all we get the time stamp... */
+ getnstimeofday(&__ts);
+
+ /* ... and translate it to PPS time data struct */
+ ts.sec = __ts.tv_sec;
+ ts.nsec = __ts.tv_nsec;
+
+ if ((event & (PPS_CAPTUREASSERT | PPS_CAPTURECLEAR)) == 0) {
+ printk(KERN_ERR "pps: unknown event (%x) for source %d\n",
+ event, source);
+ return;
+ }
+
+ spin_lock_irqsave(&idr_lock, flags);
+ pps = idr_find(&pps_idr, source);
+
+ /* If we find a valid PPS source we lock it before leaving
+ * the lock!
+ */
+ if (pps)
+ atomic_inc(&pps->usage);
+ spin_unlock_irqrestore(&idr_lock, flags);
+
+ if (!pps)
+ return;
+
+ pr_debug("PPS event on source %d at %llu.%06u\n",
+ pps->id, ts.sec, ts.nsec);
+
+ spin_lock_irqsave(&pps->lock, flags);
+
+ /* Must call the echo function? */
+ if ((pps->params.mode & (PPS_ECHOASSERT | PPS_ECHOCLEAR)))
+ pps->info.echo(source, event, data);
+
+ /* Check the event */
+ pps->current_mode = pps->params.mode;
+ if (event & PPS_CAPTUREASSERT) {
+ /* We have to add an offset? */
+ if (pps->params.mode & PPS_OFFSETASSERT)
+ pps_add_offset(&ts, &pps->params.assert_off_tu);
+
+ /* Save the time stamp */
+ pps->assert_tu = ts;
+ pps->assert_sequence++;
+ pr_debug("capture assert seq #%u for source %d\n",
+ pps->assert_sequence, source);
+ }
+ if (event & PPS_CAPTURECLEAR) {
+ /* We have to add an offset? */
+ if (pps->params.mode & PPS_OFFSETCLEAR)
+ pps_add_offset(&ts, &pps->params.clear_off_tu);
+
+ /* Save the time stamp */
+ pps->clear_tu = ts;
+ pps->clear_sequence++;
+ pr_debug("capture clear seq #%u for source %d\n",
+ pps->clear_sequence, source);
+ }
+
+ pps->go = ~0;
+ wake_up_interruptible(&pps->queue);
+
+ kill_fasync(&pps->async_queue, SIGIO, POLL_IN);
+
+ spin_unlock_irqrestore(&pps->lock, flags);
+
+ /* Now we can release the PPS source for (possible) deregistration */
+ spin_lock_irqsave(&idr_lock, flags);
+ atomic_dec(&pps->usage);
+ wake_up_all(&pps->usage_queue);
+ spin_unlock_irqrestore(&idr_lock, flags);
+}
+EXPORT_SYMBOL(pps_event);
diff --git a/drivers/pps/pps.c b/drivers/pps/pps.c
new file mode 100644
index 0000000..b3b9af8
--- /dev/null
+++ b/drivers/pps/pps.c
@@ -0,0 +1,342 @@
+/*
+ * pps.c -- Main PPS support file
+ *
+ *
+ * Copyright (C) 2005-2007 Rodolfo Giometti <[email protected]>
+ *
+ * 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/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/uaccess.h>
+#include <linux/idr.h>
+#include <linux/cdev.h>
+#include <linux/poll.h>
+#include <linux/pps.h>
+
+/*
+ * Local variables
+ */
+
+static dev_t pps_devt;
+static struct class *pps_class;
+
+/*
+ * Char device methods
+ */
+
+static unsigned int pps_cdev_poll(struct file *file, poll_table *wait)
+{
+ struct pps_device *pps = file->private_data;
+
+ poll_wait(file, &pps->queue, wait);
+
+ return POLLIN | POLLRDNORM;
+}
+
+static int pps_cdev_fasync(int fd, struct file *file, int on)
+{
+ struct pps_device *pps = file->private_data;
+ return fasync_helper(fd, file, on, &pps->async_queue);
+}
+
+static int pps_cdev_ioctl(struct inode *inode, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ struct pps_device *pps = file->private_data;
+ struct pps_kparams params;
+ struct pps_fdata fdata;
+ unsigned long ticks;
+ void __user *uarg = (void __user *) arg;
+ int __user *iuarg = (int __user *) arg;
+ int err;
+
+ switch (cmd) {
+ case PPS_CHECK:
+
+ /* This does nothing but signal we are a PPS source... */
+
+ return 0;
+
+ case PPS_GETPARAMS:
+ pr_debug("PPS_GETPARAMS: source %d\n", pps->id);
+
+ /* Sanity checks */
+ if (!uarg)
+ return -EINVAL;
+
+ /* Return current parameters */
+ err = copy_to_user(uarg, &pps->params,
+ sizeof(struct pps_kparams));
+ if (err)
+ return -EFAULT;
+
+ break;
+
+ case PPS_SETPARAMS:
+ pr_debug("PPS_SETPARAMS: source %d\n", pps->id);
+
+ /* Check the capabilities */
+ if (!capable(CAP_SYS_TIME))
+ return -EPERM;
+
+ /* Sanity checks */
+ if (!uarg)
+ return -EINVAL;
+ err = copy_from_user(¶ms, uarg, sizeof(struct pps_kparams));
+ if (err)
+ return -EFAULT;
+ if (!(params.mode & (PPS_CAPTUREASSERT | PPS_CAPTURECLEAR))) {
+ pr_debug("capture mode unspecified (%x)\n",
+ params.mode);
+ return -EINVAL;
+ }
+
+ /* Check for supported capabilities */
+ if ((params.mode & ~pps->info.mode) != 0) {
+ pr_debug("unsupported capabilities (%x)\n",
+ params.mode);
+ return -EINVAL;
+ }
+
+ spin_lock_irq(&pps->lock);
+
+ /* Save the new parameters */
+ pps->params = params;
+
+ /* Restore the read only parameters */
+ if ((params.mode & (PPS_TSFMT_TSPEC | PPS_TSFMT_NTPFP)) == 0) {
+ /* section 3.3 of RFC 2783 interpreted */
+ pr_debug("time format unspecified (%x)\n",
+ params.mode);
+ pps->params.mode |= PPS_TSFMT_TSPEC;
+ }
+ if (pps->info.mode & PPS_CANWAIT)
+ pps->params.mode |= PPS_CANWAIT;
+ pps->params.api_version = PPS_API_VERS;
+
+ spin_unlock_irq(&pps->lock);
+
+ break;
+
+ case PPS_GETCAP:
+ pr_debug("PPS_GETCAP: source %d\n", pps->id);
+
+ /* Sanity checks */
+ if (!uarg)
+ return -EINVAL;
+
+ err = put_user(pps->info.mode, iuarg);
+ if (err)
+ return -EFAULT;
+
+ break;
+
+ case PPS_FETCH:
+ pr_debug("PPS_FETCH: source %d\n", pps->id);
+
+ if (!uarg)
+ return -EINVAL;
+ err = copy_from_user(&fdata, uarg, sizeof(struct pps_fdata));
+ if (err)
+ return -EFAULT;
+
+ pps->go = 0;
+
+ /* Manage the timeout */
+ if (fdata.timeout.flags & PPS_TIME_INVALID)
+ err = wait_event_interruptible(pps->queue, pps->go);
+ else {
+ pr_debug("timeout %lld.%09d\n",
+ fdata.timeout.sec, fdata.timeout.nsec);
+ ticks = fdata.timeout.sec * HZ;
+ ticks += fdata.timeout.nsec / (NSEC_PER_SEC / HZ);
+
+ if (ticks != 0) {
+ err = wait_event_interruptible_timeout(
+ pps->queue, pps->go, ticks);
+ if (err == 0)
+ return -ETIMEDOUT;
+ }
+ }
+
+ /* Check for pending signals */
+ if (err == -ERESTARTSYS) {
+ pr_debug("pending signal caught\n");
+ return -EINTR;
+ }
+
+ /* Return the fetched timestamp */
+ spin_lock_irq(&pps->lock);
+
+ fdata.info.assert_sequence = pps->assert_sequence;
+ fdata.info.clear_sequence = pps->clear_sequence;
+ fdata.info.assert_tu = pps->assert_tu;
+ fdata.info.clear_tu = pps->clear_tu;
+ fdata.info.current_mode = pps->current_mode;
+
+ spin_unlock_irq(&pps->lock);
+
+ err = copy_to_user(uarg, &fdata, sizeof(struct pps_fdata));
+ if (err)
+ return -EFAULT;
+
+ break;
+
+ default:
+ return -ENOTTY;
+ break;
+ }
+
+ return 0;
+}
+
+static int pps_cdev_open(struct inode *inode, struct file *file)
+{
+ struct pps_device *pps = container_of(inode->i_cdev,
+ struct pps_device, cdev);
+ int found;
+
+ spin_lock_irq(&idr_lock);
+ found = idr_find(&pps_idr, pps->id) != NULL;
+
+ /* Lock the PPS source against (possible) deregistration */
+ if (found)
+ atomic_inc(&pps->usage);
+
+ spin_unlock_irq(&idr_lock);
+
+ if (!found)
+ return -ENODEV;
+
+ file->private_data = pps;
+
+ return 0;
+}
+
+static int pps_cdev_release(struct inode *inode, struct file *file)
+{
+ struct pps_device *pps = file->private_data;
+
+ /* Free the PPS source and wake up (possible) deregistration */
+ atomic_dec(&pps->usage);
+ wake_up_all(&pps->usage_queue);
+
+ return 0;
+}
+
+/*
+ * Char device stuff
+ */
+
+static const struct file_operations pps_cdev_fops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .poll = pps_cdev_poll,
+ .fasync = pps_cdev_fasync,
+ .ioctl = pps_cdev_ioctl,
+ .open = pps_cdev_open,
+ .release = pps_cdev_release,
+};
+
+int pps_register_cdev(struct pps_device *pps)
+{
+ int err;
+
+ pps->devno = MKDEV(MAJOR(pps_devt), pps->id);
+ cdev_init(&pps->cdev, &pps_cdev_fops);
+ pps->cdev.owner = pps->info.owner;
+
+ err = cdev_add(&pps->cdev, pps->devno, 1);
+ if (err) {
+ printk(KERN_ERR "pps: %s: failed to add char device %d:%d\n",
+ pps->info.name, MAJOR(pps_devt), pps->id);
+ return err;
+ }
+ pps->dev = device_create(pps_class, pps->info.dev, pps->devno,
+ "pps%d", pps->id);
+ if (err)
+ goto del_cdev;
+ dev_set_drvdata(pps->dev, pps);
+
+ pr_debug("source %s got cdev (%d:%d)\n", pps->info.name,
+ MAJOR(pps_devt), pps->id);
+
+ return 0;
+
+del_cdev:
+ cdev_del(&pps->cdev);
+
+ return err;
+}
+
+void pps_unregister_cdev(struct pps_device *pps)
+{
+ device_destroy(pps_class, pps->devno);
+ cdev_del(&pps->cdev);
+}
+
+/*
+ * Module staff
+ */
+
+static void __exit pps_exit(void)
+{
+ class_destroy(pps_class);
+
+ if (pps_devt)
+ unregister_chrdev_region(pps_devt, PPS_MAX_SOURCES);
+
+ pr_info("LinuxPPS API ver. %d removed\n", PPS_API_VERS);
+}
+
+static int __init pps_init(void)
+{
+ int err;
+
+ pps_class = class_create(THIS_MODULE, "pps");
+ if (!pps_class) {
+ printk(KERN_ERR "pps: failed to allocate class\n");
+ return -ENOMEM;
+ }
+
+ err = alloc_chrdev_region(&pps_devt, 0, PPS_MAX_SOURCES, "pps");
+ if (err < 0) {
+ printk(KERN_ERR "pps: failed to allocate char device region\n");
+ goto remove_class;
+ }
+
+ pr_info("LinuxPPS API ver. %d registered\n", PPS_API_VERS);
+ pr_info("Software ver. %s - Copyright 2005-2007 Rodolfo Giometti "
+ "<[email protected]>\n", PPS_VERSION);
+
+ return 0;
+
+remove_class:
+ class_destroy(pps_class);
+
+ return err;
+}
+
+subsys_initcall(pps_init);
+module_exit(pps_exit);
+
+MODULE_AUTHOR("Rodolfo Giometti <[email protected]>");
+MODULE_DESCRIPTION("LinuxPPS support (RFC 2783) - ver. " PPS_VERSION);
+MODULE_LICENSE("GPL");
diff --git a/drivers/pps/sysfs.c b/drivers/pps/sysfs.c
new file mode 100644
index 0000000..9b65ddd
--- /dev/null
+++ b/drivers/pps/sysfs.c
@@ -0,0 +1,142 @@
+/*
+ * sysfs.c -- sysfs support
+ *
+ *
+ * Copyright (C) 2007 Rodolfo Giometti <[email protected]>
+ *
+ * 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/device.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/pps.h>
+
+/*
+ * Attribute functions
+ */
+
+static ssize_t pps_show_assert(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct pps_device *pps = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%lld.%09d#%d\n",
+ pps->assert_tu.sec, pps->assert_tu.nsec,
+ pps->assert_sequence);
+}
+DEVICE_ATTR(assert, S_IRUGO, pps_show_assert, NULL);
+
+static ssize_t pps_show_clear(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct pps_device *pps = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%lld.%09d#%d\n",
+ pps->clear_tu.sec, pps->clear_tu.nsec,
+ pps->clear_sequence);
+}
+DEVICE_ATTR(clear, S_IRUGO, pps_show_clear, NULL);
+
+static ssize_t pps_show_mode(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct pps_device *pps = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%4x\n", pps->info.mode);
+}
+DEVICE_ATTR(mode, S_IRUGO, pps_show_mode, NULL);
+
+static ssize_t pps_show_echo(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct pps_device *pps = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%d\n", !!pps->info.echo);
+}
+DEVICE_ATTR(echo, S_IRUGO, pps_show_echo, NULL);
+
+static ssize_t pps_show_name(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct pps_device *pps = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%s\n", pps->info.name);
+}
+DEVICE_ATTR(name, S_IRUGO, pps_show_name, NULL);
+
+static ssize_t pps_show_path(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct pps_device *pps = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%s\n", pps->info.path);
+}
+DEVICE_ATTR(path, S_IRUGO, pps_show_path, NULL);
+
+/*
+ * Public functions
+ */
+
+void pps_sysfs_remove_source_entry(struct pps_device *pps)
+{
+ /* Delete info files */
+ if (pps->info.mode & PPS_CAPTUREASSERT)
+ device_remove_file(pps->dev, &dev_attr_assert);
+
+ if (pps->info.mode & PPS_CAPTURECLEAR)
+ device_remove_file(pps->dev, &dev_attr_clear);
+
+ device_remove_file(pps->dev, &dev_attr_mode);
+ device_remove_file(pps->dev, &dev_attr_echo);
+ device_remove_file(pps->dev, &dev_attr_name);
+ device_remove_file(pps->dev, &dev_attr_path);
+}
+
+int pps_sysfs_create_source_entry(struct pps_device *pps)
+{
+ int ret;
+
+ /* Create file "assert" and "clear" according to source capability */
+ if (pps->info.mode & PPS_CAPTUREASSERT) {
+ ret = device_create_file(pps->dev, &dev_attr_assert);
+ if (ret)
+ dev_err(pps->dev, "unable to create \"assert\" "
+ "sysfs entry");
+ }
+
+ if (pps->info.mode & PPS_CAPTURECLEAR) {
+ ret = device_create_file(pps->dev, &dev_attr_clear);
+ if (ret)
+ dev_err(pps->dev, "unable to create \"clear\" "
+ "sysfs entry");
+ }
+
+ ret = device_create_file(pps->dev, &dev_attr_mode);
+ if (ret)
+ dev_err(pps->dev, "unable to create \"mode\" sysfs entry");
+ ret = device_create_file(pps->dev, &dev_attr_echo);
+ if (ret)
+ dev_err(pps->dev, "unable to create \"echo\" sysfs entry");
+ ret = device_create_file(pps->dev, &dev_attr_name);
+ if (ret)
+ dev_err(pps->dev, "unable to create \"name\" sysfs entry");
+ ret = device_create_file(pps->dev, &dev_attr_path);
+ if (ret)
+ dev_err(pps->dev, "unable to create \"path\" sysfs entry");
+
+ return 0;
+}
diff --git a/include/linux/Kbuild b/include/linux/Kbuild
index c0f9bb7..93c5363 100644
--- a/include/linux/Kbuild
+++ b/include/linux/Kbuild
@@ -297,6 +297,7 @@ unifdef-y += pmu.h
unifdef-y += poll.h
unifdef-y += ppp_defs.h
unifdef-y += ppp-comp.h
+unifdef-y += pps.h
unifdef-y += ptrace.h
unifdef-y += qnx4_fs.h
unifdef-y += quota.h
diff --git a/include/linux/pps.h b/include/linux/pps.h
new file mode 100644
index 0000000..5a86109
--- /dev/null
+++ b/include/linux/pps.h
@@ -0,0 +1,204 @@
+/*
+ * pps.h -- PPS API kernel header.
+ *
+ *
+ * Copyright (C) 2005-2007 Rodolfo Giometti <[email protected]>
+ *
+ * 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 _PPS_H_
+#define _PPS_H_
+
+/* Implementation note: the logical states ``assert'' and ``clear''
+ * are implemented in terms of the chip register, i.e. ``assert''
+ * means the bit is set. */
+
+/*
+ * 3.2 New data structures
+ */
+
+#ifndef __KERNEL__
+#include <linux/types.h>
+#include <sys/time.h>
+#include <sys/ioctl.h>
+#else
+#include <linux/time.h>
+#endif
+
+#define PPS_API_VERS_1 1
+#define PPS_API_VERS PPS_API_VERS_1 /* we use API version 1 */
+#define PPS_MAX_NAME_LEN 32
+
+/* 32-bit vs. 64-bit compatibility.
+ *
+ * 0n i386, the alignment of a uint64_t is only 4 bytes, while on most other
+ * architectures it's 8 bytes. On i386, there will be no padding between the
+ * two consecutive 'struct pps_ktime' members of struct pps_kinfo and struct
+ * pps_kparams. But on most platforms there will be padding to ensure correct
+ * alignment.
+ *
+ * The simple fix is probably to add an explicit padding.
+ * [David Woodhouse]
+ */
+struct pps_ktime {
+ __s64 sec;
+ __s32 nsec;
+ __u32 flags;
+};
+#define PPS_TIME_INVALID (1<<0) /* used to specify timeout==NULL */
+
+struct pps_kinfo {
+ __u32 assert_sequence; /* seq. num. of assert event */
+ __u32 clear_sequence; /* seq. num. of clear event */
+ struct pps_ktime assert_tu; /* time of assert event */
+ struct pps_ktime clear_tu; /* time of clear event */
+ int current_mode; /* current mode bits */
+};
+
+struct pps_kparams {
+ int api_version; /* API version # */
+ int mode; /* mode bits */
+ struct pps_ktime assert_off_tu; /* offset compensation for assert */
+ struct pps_ktime clear_off_tu; /* offset compensation for clear */
+};
+
+/*
+ * 3.3 Mode bit definitions
+ */
+
+/* Device/implementation parameters */
+#define PPS_CAPTUREASSERT 0x01 /* capture assert events */
+#define PPS_CAPTURECLEAR 0x02 /* capture clear events */
+#define PPS_CAPTUREBOTH 0x03 /* capture assert and clear events */
+
+#define PPS_OFFSETASSERT 0x10 /* apply compensation for assert ev. */
+#define PPS_OFFSETCLEAR 0x20 /* apply compensation for clear ev. */
+
+#define PPS_CANWAIT 0x100 /* can we wait for an event? */
+#define PPS_CANPOLL 0x200 /* bit reserved for future use */
+
+/* Kernel actions */
+#define PPS_ECHOASSERT 0x40 /* feed back assert event to output */
+#define PPS_ECHOCLEAR 0x80 /* feed back clear event to output */
+
+/* Timestamp formats */
+#define PPS_TSFMT_TSPEC 0x1000 /* select timespec format */
+#define PPS_TSFMT_NTPFP 0x2000 /* select NTP format */
+
+/*
+ * 3.4.4 New functions: disciplining the kernel timebase
+ */
+
+/* Kernel consumers */
+#define PPS_KC_HARDPPS 0 /* hardpps() (or equivalent) */
+#define PPS_KC_HARDPPS_PLL 1 /* hardpps() constrained to
+ use a phase-locked loop */
+#define PPS_KC_HARDPPS_FLL 2 /* hardpps() constrained to
+ use a frequency-locked loop */
+/*
+ * Here begins the implementation-specific part!
+ */
+
+struct pps_fdata {
+ struct pps_kinfo info;
+ struct pps_ktime timeout;
+};
+
+#include <linux/ioctl.h>
+
+#define PPS_CHECK _IO('P', 0)
+#define PPS_GETPARAMS _IOR('P', 1, struct pps_kparams *)
+#define PPS_SETPARAMS _IOW('P', 2, struct pps_kparams *)
+#define PPS_GETCAP _IOR('P', 3, int *)
+#define PPS_FETCH _IOWR('P', 4, struct pps_fdata *)
+
+#ifdef __KERNEL__
+
+#include <linux/cdev.h>
+#include <linux/device.h>
+
+#define PPS_VERSION "5.0.0"
+#define PPS_MAX_SOURCES 16 /* should be enought... */
+
+/*
+ * Global defines
+ */
+
+/* The specific PPS source info */
+struct pps_source_info {
+ char name[PPS_MAX_NAME_LEN]; /* simbolic name */
+ char path[PPS_MAX_NAME_LEN]; /* path of connected device */
+ int mode; /* PPS's allowed mode */
+
+ void (*echo)(int source, int event, void *data); /* PPS echo function */
+
+ struct module *owner;
+ struct device *dev;
+};
+
+/* The main struct */
+struct pps_device {
+ struct pps_source_info info; /* PSS source info */
+
+ struct pps_kparams params; /* PPS's current params */
+
+ __u32 assert_sequence; /* PPS' assert event seq # */
+ __u32 clear_sequence; /* PPS' clear event seq # */
+ struct pps_ktime assert_tu;
+ struct pps_ktime clear_tu;
+ int current_mode; /* PPS mode at event time */
+
+ int go; /* PPS event is arrived? */
+ wait_queue_head_t queue; /* PPS event queue */
+
+ unsigned int id; /* PPS source unique ID */
+ struct cdev cdev;
+ struct device *dev;
+ int devno;
+ struct fasync_struct *async_queue; /* fasync method */
+ spinlock_t lock;
+
+ atomic_t usage; /* usage count */
+ wait_queue_head_t usage_queue;
+
+ struct class class_dev;
+};
+
+/*
+ * Global variables
+ */
+
+extern spinlock_t idr_lock;
+extern struct idr pps_idr;
+
+/*
+ * Exported functions
+ */
+
+extern int pps_register_source(struct pps_source_info *info,
+ int default_params);
+extern void pps_unregister_source(int source);
+extern int pps_register_cdev(struct pps_device *pps);
+extern void pps_unregister_cdev(struct pps_device *pps);
+extern void pps_event(int source, int event, void *data);
+
+extern int pps_sysfs_create_source_entry(struct pps_device *pps);
+extern void pps_sysfs_remove_source_entry(struct pps_device *pps);
+
+#endif /* __KERNEL__ */
+
+#endif /* _PPS_H_ */
--
1.5.2.5
Hi Rodolfo.
Kconfig bits are trivial and looks OK.
> diff --git a/drivers/pps/Makefile b/drivers/pps/Makefile
> new file mode 100644
> index 0000000..5a9a51b
> --- /dev/null
> +++ b/drivers/pps/Makefile
> @@ -0,0 +1,10 @@
> +#
> +# Makefile for the PPS core.
> +#
> +
> +pps_core-objs += pps.o kapi.o sysfs.o
> +obj-$(CONFIG_PPS) += pps_core.o
Please use:
pps_core-y := pps.o kapi.o sysfs.o
obj-$(CONFIG_PPS) := pps_core.o
The change from '+=' to ':=' is purely cosmetic
but I prefer this way to make it explicit that the
variables contain no other values.
> +
> +ifeq ($(CONFIG_PPS_DEBUG),y)
> +EXTRA_CFLAGS += -DDEBUG
> +endif
And this we do so today:
ccflags-$(CONFIG_PPS_DEBUG) := -DDEBUG
I did not look at the code so do not consider it reviewed by
this feedback.
Sam
On Fri, Feb 08, 2008 at 07:00:37PM +0100, Rodolfo Giometti wrote:
> This patch adds the kernel side of the PPS support currently named
> "LinuxPPS".
>
> PPS means "pulse per second" and a PPS source is just a device which
> provides a high precision signal each second so that an application
> can use it to adjust system clock time.
>
> Common use is the combination of the NTPD as userland program with a
> GPS receiver as PPS source to obtain a wallclock-time with
> sub-millisecond synchronisation to UTC.
>
> To obtain this goal the userland programs shoud use the PPS API
> specification (RFC 2783 - Pulse-Per-Second API for UNIX-like Operating
> Systems, Version 1.0) which in part is implemented by this patch. It
> provides a set of chars devices, one per PPS source, which can be used
> to get the time signal. The RFC's functions can be implemented by
> accessing to these char devices.
>
> Signed-off-by: Rodolfo Giometti <[email protected]>
> ---
> MAINTAINERS | 7 +
> drivers/Kconfig | 2 +
> drivers/Makefile | 1 +
> drivers/pps/Kconfig | 32 +++++
> drivers/pps/Makefile | 10 ++
> drivers/pps/kapi.c | 272 +++++++++++++++++++++++++++++++++++++++
> drivers/pps/pps.c | 342 ++++++++++++++++++++++++++++++++++++++++++++++++++
> drivers/pps/sysfs.c | 142 +++++++++++++++++++++
As you are adding sysfs files, please also describe them in
Documentation/ABI/ in this same series of patches.
> +void pps_sysfs_remove_source_entry(struct pps_device *pps)
> +{
> + /* Delete info files */
> + if (pps->info.mode & PPS_CAPTUREASSERT)
> + device_remove_file(pps->dev, &dev_attr_assert);
> +
> + if (pps->info.mode & PPS_CAPTURECLEAR)
> + device_remove_file(pps->dev, &dev_attr_clear);
> +
> + device_remove_file(pps->dev, &dev_attr_mode);
> + device_remove_file(pps->dev, &dev_attr_echo);
> + device_remove_file(pps->dev, &dev_attr_name);
> + device_remove_file(pps->dev, &dev_attr_path);
> +}
> +
> +int pps_sysfs_create_source_entry(struct pps_device *pps)
> +{
> + int ret;
> +
> + /* Create file "assert" and "clear" according to source capability */
> + if (pps->info.mode & PPS_CAPTUREASSERT) {
> + ret = device_create_file(pps->dev, &dev_attr_assert);
> + if (ret)
> + dev_err(pps->dev, "unable to create \"assert\" "
> + "sysfs entry");
> + }
> +
> + if (pps->info.mode & PPS_CAPTURECLEAR) {
> + ret = device_create_file(pps->dev, &dev_attr_clear);
> + if (ret)
> + dev_err(pps->dev, "unable to create \"clear\" "
> + "sysfs entry");
> + }
> +
> + ret = device_create_file(pps->dev, &dev_attr_mode);
> + if (ret)
> + dev_err(pps->dev, "unable to create \"mode\" sysfs entry");
> + ret = device_create_file(pps->dev, &dev_attr_echo);
> + if (ret)
> + dev_err(pps->dev, "unable to create \"echo\" sysfs entry");
> + ret = device_create_file(pps->dev, &dev_attr_name);
> + if (ret)
> + dev_err(pps->dev, "unable to create \"name\" sysfs entry");
> + ret = device_create_file(pps->dev, &dev_attr_path);
> + if (ret)
> + dev_err(pps->dev, "unable to create \"path\" sysfs entry");
Why not use a default attribute group?
That way the files are created before the uevent is issued, and the
amount of code you have to write is much smaller.
thanks,
greg k-h
On Fri, Feb 08, 2008 at 10:45:31PM -0800, Greg KH wrote:
>
> As you are adding sysfs files, please also describe them in
> Documentation/ABI/ in this same series of patches.
Ok. I'm going to add them under "testing".
> Why not use a default attribute group?
>
> That way the files are created before the uevent is issued, and the
> amount of code you have to write is much smaller.
What do you mean exactly? I don't understand what you wish. :'(
Thanks,
Rodolfo
--
GNU/Linux Solutions e-mail: [email protected]
Linux Device Driver [email protected]
Embedded Systems [email protected]
UNIX programming phone: +39 349 2432127
On Mon, Feb 11, 2008 at 10:53:46AM +0100, Rodolfo Giometti wrote:
> On Fri, Feb 08, 2008 at 10:45:31PM -0800, Greg KH wrote:
> >
> > As you are adding sysfs files, please also describe them in
> > Documentation/ABI/ in this same series of patches.
>
> Ok. I'm going to add them under "testing".
>
> > Why not use a default attribute group?
> >
> > That way the files are created before the uevent is issued, and the
> > amount of code you have to write is much smaller.
>
> What do you mean exactly? I don't understand what you wish. :'(
If you use a 'struct device' you can use a default attribute group for
that device to be created whenever it is added.
However you are not using the driver core that way, you are just calling
device_create(), which doesn't work that way.
But you can just use an attribute group instead, which still saves you a
lot of code, try using that instead (sysfs_create_group()).
Or go all the way and embed a 'struct device' in your structure, and
create a bus, then you can use the default attribute group, although
that might be a bit more work :)
thanks,
greg k-h
On Mon, Feb 11, 2008 at 07:25:42AM -0800, Greg KH wrote:
> On Mon, Feb 11, 2008 at 10:53:46AM +0100, Rodolfo Giometti wrote:
> > On Fri, Feb 08, 2008 at 10:45:31PM -0800, Greg KH wrote:
> > >
> > > As you are adding sysfs files, please also describe them in
> > > Documentation/ABI/ in this same series of patches.
> >
> > Ok. I'm going to add them under "testing".
> >
> > > Why not use a default attribute group?
> > >
> > > That way the files are created before the uevent is issued, and the
> > > amount of code you have to write is much smaller.
> >
> > What do you mean exactly? I don't understand what you wish. :'(
>
> If you use a 'struct device' you can use a default attribute group for
> that device to be created whenever it is added.
>
> However you are not using the driver core that way, you are just calling
> device_create(), which doesn't work that way.
>
> But you can just use an attribute group instead, which still saves you a
> lot of code, try using that instead (sysfs_create_group()).
>
> Or go all the way and embed a 'struct device' in your structure, and
> create a bus, then you can use the default attribute group, although
> that might be a bit more work :)
I see but how can I manage the fact that files "assert" and "clear"
are created according to pps->info.mode field content?
See the code:
int pps_sysfs_create_source_entry(struct pps_device *pps)
{
int ret;
/* Create file "assert" and "clear" according to source capability */
if (pps->info.mode & PPS_CAPTUREASSERT) {
ret = device_create_file(pps->dev, &dev_attr_assert);
if (ret)
dev_err(pps->dev, "unable to create \"assert\" "
"sysfs entry");
}
if (pps->info.mode & PPS_CAPTURECLEAR) {
ret = device_create_file(pps->dev, &dev_attr_clear);
if (ret)
dev_err(pps->dev, "unable to create \"clear\" "
"sysfs entry");
}
ret = device_create_file(pps->dev, &dev_attr_mode);
if (ret)
dev_err(pps->dev, "unable to create \"mode\" sysfs entry");
Do you think is better create these files anyway and in case report a
NULL string?
Thanks,
Rodolfo
--
GNU/Linux Solutions e-mail: [email protected]
Linux Device Driver [email protected]
Embedded Systems [email protected]
UNIX programming phone: +39 349 2432127
On Mon, Feb 11, 2008 at 07:31:53PM +0100, Rodolfo Giometti wrote:
> Do you think is better create these files anyway and in case report a
> NULL string?
Is that ok?
/*
* Attribute functions
*/
static ssize_t pps_show_assert(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct pps_device *pps = dev_get_drvdata(dev);
if (!(pps->info.mode & PPS_CAPTUREASSERT))
return 0;
return sprintf(buf, "%lld.%09d#%d\n",
pps->assert_tu.sec, pps->assert_tu.nsec,
pps->assert_sequence);
}
DEVICE_ATTR(assert, S_IRUGO, pps_show_assert, NULL);
static ssize_t pps_show_clear(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct pps_device *pps = dev_get_drvdata(dev);
if (!(pps->info.mode & PPS_CAPTURECLEAR))
return 0;
return sprintf(buf, "%lld.%09d#%d\n",
pps->clear_tu.sec, pps->clear_tu.nsec,
pps->clear_sequence);
}
DEVICE_ATTR(clear, S_IRUGO, pps_show_clear, NULL);
static ssize_t pps_show_mode(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct pps_device *pps = dev_get_drvdata(dev);
return sprintf(buf, "%4x\n", pps->info.mode);
}
DEVICE_ATTR(mode, S_IRUGO, pps_show_mode, NULL);
...
static struct attribute *pps_attrs[] = {
&dev_attr_mode.attr,
&dev_attr_echo.attr,
&dev_attr_name.attr,
&dev_attr_path.attr,
&dev_attr_assert.attr,
&dev_attr_clear.attr,
NULL
};
static struct attribute_group pps_group = {
.attrs = pps_attrs,
};
/*
* Public functions
*/
void pps_sysfs_remove_source_entry(struct pps_device *pps)
{
/* Delete info files */
sysfs_remove_group(&pps->dev->kobj, &pps_group);
}
int pps_sysfs_create_source_entry(struct pps_device *pps)
{
int ret;
/* Create info files */
ret = sysfs_create_group(&pps->dev->kobj, &pps_group);
if (ret)
dev_err(pps->dev, "unable to create default sysfs entries");
return 0;
}
Ciao,
Rodolfo
--
GNU/Linux Solutions e-mail: [email protected]
Linux Device Driver [email protected]
Embedded Systems [email protected]
UNIX programming phone: +39 349 2432127