Re: [PATCH 1/1] LinuxPPS: Pulse per Second support for Linux
From: Rodolfo Giometti
Date: Sat May 12 2007 - 02:00:11 EST
Hello,
here my new patch with a lot of fixes.
The only issue not still fixed is the one related with:
#define NETLINK_PPSAPI 20
I need time to resolve it.
Follows my comments and then the patch, hope now I can came back into
-mm tree again! :)
On Thu, May 10, 2007 at 12:27:52AM -0700, akpm@xxxxxxxxxxxxxxxxxxxx wrote:
>
> Review comments:
>
> - Running a timer once per second will make the super-low-power people upset.
The ktimer modules is just for debugging pourpose and it's not needed
into real working system.
> - This uses netlink? Is that interface documented anywhere?
>
> Please check with Dave Miller that this:
>
> #define NETLINK_PPSAPI 20
>
> reservation is OK.
Is not ok. To be fixed.
> - This:
>
> if ((nlpps->tsformat != PPS_TSFMT_TSPEC) != 0 ) {
>
> is weird. I changed it to
>
> if (nlpps->tsformat != PPS_TSFMT_TSPEC) {
Fixed.
> - This:
>
> timeout += nlpps->timeout.tv_nsec/(1000000000/HZ);
>
> probably won't work on i386. We use do_div() for 64/32 divides. I'll
> find out when I compile it.
>
> It's nice to use NSEC_PER_SEC rather than having to count all those
> zeroes.
Fixed.
> - The code uses interruptible_sleep_on_timeout(). That API is deprecated
> and is racy. Please convert to wait_event_interruptible_timeout().
>
> Ditto interruptible_sleep_on()
Fixed.
> - This:
>
> memset(pps_source, 0, sizeof(struct pps_s) * PPS_MAX_SOURCES);
>
> was unneeded. The C startup code already did that.
Fixed.
> - All these separators:
>
> +/* --- Input function ------------------------------------------------------
+*/
>
> aren't typical for kernel code. I left them in, but please consider
> removing them all.
Fixed.
> - This:
>
> static void pps_class_release(struct class_device *cdev)
> {
> /* Nop??? */
> }
>
> is a bug and it earns you a nastygram from Greg. These objects must be
> dynamically allocated - this is not optional.
It could be acceptable defining this function as void?
> - What's this doing in 8250.c?
>
> + if (up->port.flags & UPF_HARDPPS_CD)
> + up->ier |= UART_IER_MSI; /* enable interrupts */
>
> Please fully describe the reasons for this change in the changelog, and in
> a code comment and then get the change reviewed by Russell King
> <rmk@xxxxxxxxxxxxxxxx>.
If user specify a serial port as PPS source we enable IRQ on that
port.
> - Please document within the changelog the other changes to the serial code
> and we'll ask Russell to take a look at those as well.
OK. I'll do it.
> - The Kconfig purports to support CONFIG_PPS=m. Does that actually work?
Yes. It works...
> We have a bunch of code in random other drivers which is dependent upon
> CONFIG_PPS_CLIENT_foo. The problem is that if a kernel was compiled with
> CONFIG_PPS_CLIENT_foo=n and then the pps driver is later built for that
> kernel, it won't actually work because lp, serial etc weren't correctly
> configured when _they_ were built.
>
> This sort of cross-module coupling is considered to be a bad thing, but
> I'm not really sure it's all that important.
>
> - Please split the patch up into a series of patches: one for pps core and
> one for each of the clients (servers?): one for lp, one for serial, etc.
>
> Try to arrange for that series of patches to build and run at each stage
> of application.
>
> Please don't lose my changes when you do so ;)
>
> Please review the changes I made and a) stick to the same style and b) fix
> up any sites which I missed.
>
> - Please remove all the typedefs:
>
> +typedef struct ntp_fp {
> +typedef union pps_timeu {
> +typedef struct pps_info {
> +typedef struct pps_params {
>
> and just use `struct ntp_fp' everywhere.
Those typedefs are defined in PPS specifications (please, see RFC 2783).
> - The above four structures are communicated with userspace, yes?
>
> I believe that they will not work correctly when 32-bit userspace is
> communicating with a 64-bit kernel. Alignments change and sizeof(long)
> changes.
>
> You don't want to have to write compat code. I suggest that you redo
> those structures in terms of __u32, __u64, etc. You probably need to use
> attribute((packed)) too, not sure.
>
> Then let's get that part carefully reviewed (Arnd Bergmann <arnd@xxxxxxxx>
> is my go-to guru on this) and please test it carefully.
>
> Yeah, you just haven't got a chance that something as huge and as complex
> as struct pps_netlink_msg will survive the 32->64 transition.
The same as above. These structure are fixed by RFC 2783.
> - Please ensure that `make headers_check' passes OK (you'll hear from me if
> it doesn't ;))
Done.
> - Can we get rid of the private dbg, err and info macros? Surely there are
> generic ones somewhere.
They are very useful to LinuxPPS users who can enable/disable them by
configuration menu.
Also I'm planning to add a dinamic enable/disable mechanism...
> - struct pps_s has volatiles in it. Please remove them. There's lots of
> discussion on this topic on linux-kernel just today.
Fixed.
> - Why did the
>
> port->icount.dcd++;
>
> get moved in uart_handle_dcd_change()?
That's why we have to register the PPS interrupt as soon as possible!
Even few CPU instructions dalay may result in a bad time settings.
> - In lots of places you do:
>
> +#ifdef CONFIG_PPS_CLIENT_UART
> +#include <linux/pps.h>
> +#endif
>
> Please remove the ifdefs at all these sites and make the header file
> handle it.
Fixed.
> - It no longer compiles, because netlink_kernel_create now requires a
> `struct mutex *'. I stuck a NULL in there, which is permitted. But I don't> know if that was a good thing - please check this.
>
> Please also chase the net guys with a pointy stick for failing to document
> their damned APIs.
This should vanish when new netlink layer will be used.
> - Generally: code looks OK and is probably useful. Please keep going ;)
Hope I forgot nothing!
Ciao,
Rodolfo
----
diff --git a/Documentation/pps.txt b/Documentation/pps.txt
new file mode 100644
index 0000000..f07b098
--- /dev/null
+++ b/Documentation/pps.txt
@@ -0,0 +1,183 @@
+
+ PPS - Pulse Per Second
+ ----------------------
+
+(C) Copyright 2007 Rodolfo Giometti <giometti@xxxxxxxxxxxx>
+
+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 change the original RFC 2783:
+
+ pps_handle_t type is an opaque __scalar type__ used to represent a
+ PPS source within the API
+
+into a modified:
+
+ pps_handle_t type is an opaque __variable__ used to represent a PPS
+ source within the API and programs should not access it directly to
+ it due to its opacity.
+
+This change seems to be neglibile because even the original RFC 2783
+does not encourage programs to check (read: use) the pps_handle_t
+variable before calling the time_pps_*() functions, since each
+function should do this job internally.
+
+If I intentionally separate the concept of "file descriptor" from the
+concept of the "PPS source" I'm obliged to provide a solution to find
+and register a PPS-source without using a file descriptor: it's done
+by the functions time_pps_findsource() and time_pps_findpath() now.
+
+According to this current NTPD drivers' code should be modified as
+follows:
+
++#ifdef PPS_HAVE_FINDPATH
++ /* Get the PPS source's real name */
++ fd = readlink(link, path, STRING_LEN-1);
++ if (fd <= 0)
++ strncpy(path, link, STRING_LEN);
++ else
++ path[fd] = '\0';
++
++ /* Try to find the source */
++ fd = time_pps_findpath(path, STRING_LEN, id, STRING_LEN);
++ if (fd < 0) {
++ msyslog(LOG_ERR, "refclock: cannot find PPS source \"%s\" in the system", path);
++ return 1;
++ }
++ msyslog(LOG_INFO, "refclock: found PPS source #%d \"%s\" on \"%s\"", fd, path, id);
++#endif /* PPS_HAVE_FINDPATH */
++
++
+ if (time_pps_create(fd, &pps_handle) < 0) {
+- pps_handle = 0;
+ msyslog(LOG_ERR, "refclock: time_pps_create failed: %m");
+ }
+
+
+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,
+ };
+
+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,
+ -1 /* is up to the system */);
+
+The pps_register_source() prototype is:
+
+ int pps_register_source(struct pps_source_info_s *info, int default_params, int try_id)
+
+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)
+and "try_id" can be used to force a particular ID for your device into
+the system (just use -1 if you wish the system chooses one for you).
+
+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
+-------------
+
+The SYSFS support is enabled by default if the SYSFS filesystem is
+enabled in the kernel and it provides a new class:
+
+ $ ls /sys/class/pps/
+ 00/ 01/ 02/
+
+Every directory is the ID of a PPS sources defined into the system and
+inside you find several files:
+
+ $ ls /sys/class/pps/00/
+ 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/00/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).
diff --git a/MAINTAINERS b/MAINTAINERS
index cfd26dd..dd6784d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2860,6 +2860,13 @@ P: Michal Ostrowski
M: mostrows@xxxxxxxxxxxxx
S: Maintained
+PPS SUPPORT
+P: Rodolfo Giometti
+M: giometti@xxxxxxxxxxxx
+W: http://wiki.enneenne.com/index.php/LinuxPPS_support
+L: linuxpps@xxxxxxxxxxxxxxx
+S: Maintained
+
PREEMPTIBLE KERNEL
P: Robert Love
M: rml@xxxxxxxxx
diff --git a/drivers/Kconfig b/drivers/Kconfig
index 050323f..bb54cab 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/hwmon/Kconfig"
diff --git a/drivers/Makefile b/drivers/Makefile
index 26ca903..97dc041 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -59,6 +59,7 @@ 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_HWMON) += hwmon/
obj-$(CONFIG_PHONE) += telephony/
diff --git a/drivers/char/lp.c b/drivers/char/lp.c
index 62051f8..a50b336 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 };
@@ -817,6 +838,35 @@ static int lp_register(int nr, struct parport *port)
}
#endif
+#ifdef CONFIG_PPS_CLIENT_LP
+ 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,
+ -1 /* is up to the system */);
+ if (port->pps_source < 0)
+ pps_err("cannot register PPS source \"%s\"",
+ port->pps_info.path);
+ else
+ pps_info("PPS source #%d \"%s\" added to the system",
+ port->pps_source, port->pps_info.path);
+ } else {
+ port->pps_source = -1;
+ pps_err("PPS support disabled due port \"%s\" is in polling mode",
+ port->pps_info.path);
+ }
+#endif
+
return 0;
}
@@ -860,6 +910,14 @@ 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_info));
+ pps_dbg("PPS source #%d \"%s\" removed from the system",
+ port->pps_source, port->pps_info.path);
+ }
+#endif
}
static struct parport_driver lp_driver = {
diff --git a/drivers/pps/Kconfig b/drivers/pps/Kconfig
new file mode 100644
index 0000000..54297e8
--- /dev/null
+++ b/drivers/pps/Kconfig
@@ -0,0 +1,34 @@
+#
+# Character device 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
+ antennas. Userland can use it to get an high time reference.
+
+ Some antennas' 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 antennas' PPS signals are connected with some special host
+ inputs so you have to enable the corresponding client support.
+
+ This PPS support can also be built as a module. If so, the module
+ will be called pps-core.
+
+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.
+
+source drivers/pps/clients/Kconfig
+
+endmenu
diff --git a/drivers/pps/Makefile b/drivers/pps/Makefile
new file mode 100644
index 0000000..76101cd
--- /dev/null
+++ b/drivers/pps/Makefile
@@ -0,0 +1,7 @@
+#
+# Makefile for the PPS core.
+#
+
+pps_core-objs += pps.o kapi.o sysfs.o
+obj-$(CONFIG_PPS) += pps_core.o
+obj-y += clients/
diff --git a/drivers/pps/clients/Kconfig b/drivers/pps/clients/Kconfig
new file mode 100644
index 0000000..a87cd37
--- /dev/null
+++ b/drivers/pps/clients/Kconfig
@@ -0,0 +1,38 @@
+#
+# LinuxPPS 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.o.
+
+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.
+
+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/drivers/pps/clients/Makefile b/drivers/pps/clients/Makefile
new file mode 100644
index 0000000..3ecca41
--- /dev/null
+++ b/drivers/pps/clients/Makefile
@@ -0,0 +1,6 @@
+#
+# Makefile for miscellaneous I2C chip drivers.
+#
+
+obj-$(CONFIG_PPS_CLIENT_KTIMER) += ktimer.o
+
diff --git a/drivers/pps/clients/ktimer.c b/drivers/pps/clients/ktimer.c
new file mode 100644
index 0000000..e9e5c47
--- /dev/null
+++ b/drivers/pps/clients/ktimer.c
@@ -0,0 +1,113 @@
+/*
+ * ktimer.c -- kernel timer test client
+ *
+ *
+ * Copyright (C) 2005-2006 Rodolfo Giometti <giometti@xxxxxxxx>
+ *
+ * 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)
+{
+ pps_info("PPS event at %lu", 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)
+{
+ pps_info("echo %s %s for source %d",
+ event & PPS_CAPTUREASSERT ? "assert" : "",
+ event & PPS_CAPTURECLEAR ? "clear" : "",
+ source);
+}
+
+/*
+ * The PPS info struct
+ */
+
+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,
+};
+
+/*
+ * Module staff
+ */
+
+static void __exit pps_ktimer_exit(void)
+{
+ del_timer_sync(&ktimer);
+ pps_unregister_source(&pps_ktimer_info);
+
+ pps_info("ktimer PPS source unregistered");
+}
+
+static int __init pps_ktimer_init(void)
+{
+ int ret;
+
+ ret = pps_register_source(&pps_ktimer_info,
+ PPS_CAPTUREASSERT|PPS_OFFSETASSERT,
+ -1 /* is up to the system */);
+ if (ret < 0) {
+ pps_err("cannot register ktimer source");
+ return ret;
+ }
+ source = ret;
+
+ setup_timer(&ktimer, pps_ktimer_event, 0);
+ mod_timer(&ktimer, jiffies + HZ);
+
+ pps_info("ktimer PPS source registered at %d", source);
+
+ return 0;
+}
+
+module_init(pps_ktimer_init);
+module_exit(pps_ktimer_exit);
+
+MODULE_AUTHOR("Rodolfo Giometti <giometti@xxxxxxxx>");
+MODULE_DESCRIPTION("testing PPS source by using a kernel timer (just for debug)");
+MODULE_LICENSE("GPL");
diff --git a/drivers/pps/kapi.c b/drivers/pps/kapi.c
new file mode 100644
index 0000000..033b308
--- /dev/null
+++ b/drivers/pps/kapi.c
@@ -0,0 +1,202 @@
+/*
+ * kapi.c -- kernel API
+ *
+ *
+ * Copyright (C) 2005-2007 Rodolfo Giometti <giometti@xxxxxxxx>
+ *
+ * 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/pps.h>
+
+/*
+ * Local functions
+ */
+
+static void pps_add_offset(struct timespec *ts, struct timespec *offset)
+{
+ ts->tv_nsec += offset->tv_nsec;
+ if (ts->tv_nsec >= NSEC_PER_SEC) {
+ ts->tv_nsec -= NSEC_PER_SEC;
+ ts->tv_sec++;
+ } else if (ts->tv_nsec < 0) {
+ ts->tv_nsec += NSEC_PER_SEC;
+ ts->tv_sec--;
+ }
+ ts->tv_sec += offset->tv_sec;
+}
+
+/*
+ * Exported functions
+ */
+
+static int __pps_register_source(struct pps_source_info_s *info,
+ int default_params, int try_id)
+{
+ int i;
+
+ if (try_id >= 0) {
+ if (pps_is_allocated(try_id)) {
+ pps_err("source id %d busy", try_id);
+ return -EBUSY;
+ }
+ i = try_id;
+ } else {
+ for (i = 0; i < PPS_MAX_SOURCES; i++)
+ if (!pps_is_allocated(i))
+ break;
+ if (i >= PPS_MAX_SOURCES) {
+ pps_err("no free source ids");
+ return -ENOMEM;
+ }
+ }
+
+ /* Sanity checks */
+ if ((info->mode & default_params) != default_params) {
+ pps_err("unsupported default parameters");
+ return -EINVAL;
+ }
+ if ((info->mode & (PPS_ECHOASSERT|PPS_ECHOCLEAR)) != 0 &&
+ info->echo == NULL) {
+ pps_err("echo function is not defined");
+ return -EINVAL;
+ }
+ if ((info->mode & (PPS_TSFMT_TSPEC|PPS_TSFMT_NTPFP)) == 0) {
+ pps_err("unspecified time format");
+ return -EINVAL;
+ }
+
+ /* Allocate the PPS source */
+ memset(&pps_source[i], 0, sizeof(struct pps_s));
+ pps_source[i].info = info;
+ pps_source[i].params.api_version = PPS_API_VERS;
+ pps_source[i].params.mode = default_params;
+ init_waitqueue_head(&pps_source[i].queue);
+
+ return i;
+}
+
+int pps_register_source(struct pps_source_info_s *info, int default_params,
+ int try_id)
+{
+ unsigned long flags;
+ int i, ret;
+
+ spin_lock_irqsave(&pps_lock, flags);
+ ret = __pps_register_source(info, default_params, try_id);
+ spin_unlock_irqrestore(&pps_lock, flags);
+
+ if (ret < 0)
+ return ret;
+ i = ret;
+
+ ret = pps_sysfs_create_source_entry(info, i);
+ if (ret < 0)
+ pps_err("unable to create sysfs entry for source %d", i);
+
+ return i;
+}
+EXPORT_SYMBOL(pps_register_source);
+
+static void __pps_unregister_source(struct pps_source_info_s *info)
+{
+ int i;
+
+ for (i = 0; i < PPS_MAX_SOURCES; i++)
+ if (pps_is_allocated(i) && pps_source[i].info == info)
+ break;
+
+ if (i >= PPS_MAX_SOURCES) {
+ pps_err("warning! Try to unregister an unknow PPS source");
+ return;
+ }
+
+ /* Deallocate the PPS source */
+ pps_source[i].info = NULL;
+}
+
+void pps_unregister_source(struct pps_source_info_s *info)
+{
+ unsigned long flags;
+
+ pps_sysfs_remove_source_entry(info);
+
+ spin_lock_irqsave(&pps_lock, flags);
+ __pps_unregister_source(info);
+ spin_unlock_irqrestore(&pps_lock, flags);
+}
+EXPORT_SYMBOL(pps_unregister_source);
+
+void pps_event(int source, int event, void *data)
+{
+ struct timespec ts;
+
+ /* In this function we shouldn't need locking at all since each PPS
+ * source arrives once per second and due the per-PPS source data
+ * array... */
+
+ /* First of all we get the time stamp... */
+ getnstimeofday(&ts);
+
+ /* ... then we can do some sanity checks */
+ if (!pps_is_allocated(source)) {
+ pps_err("unknow source for event!");
+ return;
+ }
+ if ((event & (PPS_CAPTUREASSERT|PPS_CAPTURECLEAR)) == 0 ) {
+ pps_err("unknow event (%x) for source %d", event, source);
+ return;
+ }
+
+ /* Must call the echo function? */
+ if ((pps_source[source].params.mode & (PPS_ECHOASSERT|PPS_ECHOCLEAR)) != 0)
+ pps_source[source].info->echo(source, event, data);
+
+ /* Check the event */
+ pps_source[source].current_mode = pps_source[source].params.mode;
+ if (event & PPS_CAPTUREASSERT) {
+ /* We have to add an offset? */
+ if (pps_source[source].params.mode&PPS_OFFSETASSERT)
+ pps_add_offset(&ts,
+ &pps_source[source].params.assert_off_tu.tspec);
+
+ /* Save the time stamp */
+ pps_source[source].assert_tu.tspec = ts;
+ pps_source[source].assert_sequence++;
+ pps_dbg("capture assert seq #%lu for source %d",
+ pps_source[source].assert_sequence, source);
+ }
+ if (event & PPS_CAPTURECLEAR) {
+ /* We have to add an offset? */
+ if (pps_source[source].params.mode&PPS_OFFSETCLEAR)
+ pps_add_offset(&ts,
+ &pps_source[source].params.clear_off_tu.tspec);
+
+ /* Save the time stamp */
+ pps_source[source].clear_tu.tspec = ts;
+ pps_source[source].clear_sequence++;
+ pps_dbg("capture clear seq #%lu for source %d",
+ pps_source[source].clear_sequence, source);
+ }
+
+ pps_source[source].go = ~0;
+ wake_up_interruptible(&pps_source[source].queue);
+}
+EXPORT_SYMBOL(pps_event);
diff --git a/drivers/pps/pps.c b/drivers/pps/pps.c
new file mode 100644
index 0000000..30d6a26
--- /dev/null
+++ b/drivers/pps/pps.c
@@ -0,0 +1,371 @@
+/*
+ * pps.c -- Main PPS support file
+ *
+ *
+ * Copyright (C) 2005-2007 Rodolfo Giometti <giometti@xxxxxxxx>
+ *
+ * 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/version.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/skbuff.h>
+
+#include <linux/pps.h>
+
+/*
+ * Global variables
+ */
+
+struct pps_s pps_source[PPS_MAX_SOURCES];
+DEFINE_SPINLOCK(pps_lock);
+
+/*
+ * Local variables
+ */
+
+static struct sock *nl_sk = NULL;
+
+/*
+ * Misc functions
+ */
+
+static inline int pps_check_source(int source)
+{
+ return (source < 0 || !pps_is_allocated(source)) ? -EINVAL : 0;
+}
+
+static int pps_find_source(int source)
+{
+ int i;
+
+ if (source >= 0) {
+ if (source >= PPS_MAX_SOURCES || !pps_is_allocated(source))
+ return -EINVAL;
+ else
+ return source;
+ }
+
+ for (i = 0; i < PPS_MAX_SOURCES; i++)
+ if (pps_is_allocated(i))
+ break;
+
+ if (i >= PPS_MAX_SOURCES)
+ return -EINVAL;
+
+ return i;
+}
+
+static int pps_find_path(char *path)
+{
+ int i;
+
+ for (i = 0; i < PPS_MAX_SOURCES; i++)
+ if (pps_is_allocated(i) &&
+ (strncmp(pps_source[i].info->path, path,
+ PPS_MAX_NAME_LEN) == 0 ||
+ strncmp(pps_source[i].info->name, path,
+ PPS_MAX_NAME_LEN) == 0))
+ break;
+
+ if (i >= PPS_MAX_SOURCES)
+ return -EINVAL;
+
+ return i;
+}
+
+/*
+ * Input function
+ */
+
+static void pps_nl_data_ready(struct sock *sk, int len)
+{
+ struct sk_buff *skb;
+ struct nlmsghdr *nlh;
+ struct pps_netlink_msg *nlpps;
+ int cmd, source, id;
+ unsigned long timeout;
+ int ret;
+
+ while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
+ nlh = (struct nlmsghdr *) skb->data;
+ pps_dbg("New message from PID %d (flags %x)",
+ nlh->nlmsg_pid, nlh->nlmsg_flags);
+
+ /* Decode the userland command */
+ nlpps = (struct pps_netlink_msg*) NLMSG_DATA(nlh);
+ cmd = nlpps->cmd;
+ source = nlpps->source;
+
+ switch (cmd) {
+ case PPS_CREATE:
+ pps_dbg("PPS_CREATE: source %d", source);
+
+ /* Check if the requested source is allocated */
+ ret = pps_find_source(source);
+ if (ret < 0) {
+ nlpps->ret = ret;
+ break;
+ }
+
+ nlpps->source = ret;
+ nlpps->ret = 0;
+ break;
+
+ case PPS_DESTROY:
+ pps_dbg("PPS_DESTROY: source %d", source);
+
+ /* Nothing to do here! Just answer ok... */
+ nlpps->ret = 0;
+ break;
+
+ case PPS_SETPARMS:
+ pps_dbg("PPS_SETPARMS: source %d", source);
+
+ /* Check the capabilities */
+ if (!capable(CAP_SYS_TIME)) {
+ nlpps->ret = -EPERM;
+ break;
+ }
+
+ /* Sanity checks */
+ ret = pps_check_source(source);
+ if (ret < 0) {
+ nlpps->ret = ret;
+ break;
+ }
+ if ((nlpps->params.mode & ~pps_source[source].info->mode) != 0) {
+ pps_dbg("unsupported capabilities");
+ nlpps->ret = -EINVAL;
+ break;
+ }
+ if ((nlpps->params.mode & (PPS_CAPTUREASSERT|PPS_CAPTURECLEAR)) == 0) {
+ pps_dbg("capture mode unspecified");
+ nlpps->ret = -EINVAL;
+ break;
+ }
+ if ((nlpps->params.mode & (PPS_TSFMT_TSPEC|PPS_TSFMT_NTPFP)) == 0) {
+ /* section 3.3 of RFC 2783 interpreted */
+ pps_dbg("time format unspecified");
+ nlpps->params.mode |= PPS_TSFMT_TSPEC;
+ }
+
+ /* Save the new parameters */
+ pps_source[source].params = nlpps->params;
+
+ /* Restore the read only parameters */
+ if (pps_source[source].info->mode&PPS_CANWAIT)
+ pps_source[source].params.mode |= PPS_CANWAIT;
+ pps_source[source].params.api_version = PPS_API_VERS;
+
+ nlpps->ret = 0;
+ break;
+
+ case PPS_GETPARMS:
+ pps_dbg("PPS_GETPARMS: source %d", source);
+
+ /* Sanity checks */
+ ret = pps_check_source(source);
+ if (ret < 0) {
+ nlpps->ret = ret;
+ break;
+ }
+
+ nlpps->params = pps_source[source].params;
+ nlpps->ret = 0;
+ break;
+
+ case PPS_GETCAP:
+ pps_dbg("PPS_GETCAP: source %d", source);
+
+ /* Sanity checks */
+ ret = pps_check_source(source);
+ if (ret < 0) {
+ nlpps->ret = ret;
+ break;
+ }
+
+ nlpps->mode = pps_source[source].info->mode;
+ nlpps->ret = 0;
+ break;
+
+ case PPS_FETCH:
+ pps_dbg("PPS_FETCH: source %d", source);
+
+ /* Sanity checks */
+ ret = pps_check_source(source);
+ if (ret < 0) {
+ nlpps->ret = ret;
+ break;
+ }
+ if (nlpps->tsformat != PPS_TSFMT_TSPEC) {
+ pps_dbg("unsupported time format");
+ nlpps->ret = -EINVAL;
+ break;
+ }
+
+ pps_source[source].go = 0;
+
+ /* Manage the timeout */
+ if (nlpps->timeout.tv_sec != -1) {
+ timeout = nlpps->timeout.tv_sec * HZ;
+ timeout += nlpps->timeout.tv_nsec/
+ (NSEC_PER_SEC/HZ);
+
+ if (timeout != 0) {
+ ret = wait_event_interruptible_timeout(
+ pps_source[source].queue,
+ pps_source[source].go, timeout);
+ if (ret == 0) {
+ pps_dbg("timeout expired");
+ nlpps->ret = -ETIMEDOUT;
+ break;
+ }
+ }
+ } else
+ ret = wait_event_interruptible(
+ pps_source[source].queue,
+ pps_source[source].go);
+
+ /* Check for pending signals */
+ if (ret == -ERESTARTSYS) {
+ pps_dbg("pending signal caught");
+ nlpps->ret = -EINTR;
+ break;
+ }
+
+ /* Return the fetched timestamp */
+ nlpps->info.assert_sequence = pps_source[source].assert_sequence;
+ nlpps->info.clear_sequence = pps_source[source].clear_sequence;
+ nlpps->info.assert_tu = pps_source[source].assert_tu;
+ nlpps->info.clear_tu = pps_source[source].clear_tu;
+ nlpps->info.current_mode = pps_source[source].current_mode;
+
+ nlpps->ret = 0;
+ break;
+
+ case PPS_KC_BIND:
+ pps_dbg("PPS_KC_BIND: source %d", source);
+ /* Feature currently not supported */
+ nlpps->ret = -EOPNOTSUPP;
+ break;
+
+ case PPS_FIND_SRC:
+ pps_dbg("PPS_FIND_SRC: source %d", source);
+ source = pps_find_source(source);
+ if (source < 0) {
+ pps_dbg("no PPS devices found");
+ nlpps->ret = -ENODEV;
+ break;
+ }
+
+ /* Found! So copy the info */
+ nlpps->source = source;
+ strncpy(nlpps->name, pps_source[source].info->name,
+ PPS_MAX_NAME_LEN);
+ strncpy(nlpps->path, pps_source[source].info->path,
+ PPS_MAX_NAME_LEN);
+ nlpps->ret = 0;
+ break;
+
+ case PPS_FIND_PATH:
+ pps_dbg("PPS_FIND_PATH: source %s", nlpps->path);
+ source = pps_find_path(nlpps->path);
+ if (source < 0) {
+ pps_dbg("no PPS devices found");
+ nlpps->ret = -ENODEV;
+ break;
+ }
+
+ /* Found! So copy the info */
+ nlpps->source = source;
+ strncpy(nlpps->name, pps_source[source].info->name,
+ PPS_MAX_NAME_LEN);
+ strncpy(nlpps->path, pps_source[source].info->path,
+ PPS_MAX_NAME_LEN);
+ nlpps->ret = 0;
+ break;
+
+ default:
+ /* Unknow command */
+ pps_dbg("unknow command %d", nlpps->cmd);
+
+ nlpps->ret = -EINVAL;
+ }
+
+ /* Send an answer to the userland */
+ id = NETLINK_CB(skb).pid;
+ pps_dbg("start sending reply to ID %d...", id);
+ NETLINK_CB(skb).pid = 0; /* from the kernel */
+ NETLINK_CB(skb).dst_group = 0; /* not in mcast groups */
+
+ ret = netlink_unicast(nl_sk, skb, id, MSG_DONTWAIT);
+ pps_dbg("... reply sent (%d)", ret);
+ }
+}
+
+/*
+ * Module staff
+ */
+
+static void __exit pps_exit(void)
+{
+ pps_sysfs_unregister();
+ sock_release(nl_sk->sk_socket);
+
+ pps_info("LinuxPPS API ver. %d removed", PPS_API_VERS);
+}
+
+static int __init pps_init(void)
+{
+ int ret;
+
+ nl_sk = netlink_kernel_create(NETLINK_PPSAPI, 0,
+ pps_nl_data_ready, NULL, THIS_MODULE);
+ if (nl_sk == NULL) {
+ pps_err("unable to create netlink kernel socket");
+ return -EBUSY;
+ }
+ pps_dbg("netlink protocol %d created", NETLINK_PPSAPI);
+
+ /* Register to sysfs */
+ ret = pps_sysfs_register();
+ if (ret < 0) {
+ pps_err("unable to register sysfs");
+ goto pps_sysfs_register_error;
+ }
+
+ pps_info("LinuxPPS API ver. %d registered", PPS_API_VERS);
+ pps_info("Software ver. %s - Copyright 2005-2007 Rodolfo Giometti "
+ "<giometti@xxxxxxxx>", PPS_VERSION);
+
+ return 0;
+
+pps_sysfs_register_error:
+
+ sock_release(nl_sk->sk_socket);
+
+ return ret;
+}
+
+subsys_initcall(pps_init);
+module_exit(pps_exit);
+
+MODULE_AUTHOR("Rodolfo Giometti <giometti@xxxxxxxx>");
+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..0dae24b
--- /dev/null
+++ b/drivers/pps/sysfs.c
@@ -0,0 +1,219 @@
+/*
+ * sysfs.c -- sysfs support
+ *
+ *
+ * Copyright (C) 2007 Rodolfo Giometti <giometti@xxxxxxxx>
+ *
+ * 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>
+
+/*
+ * Private functions
+ */
+
+static ssize_t pps_show_assert(struct class_device *cdev, char *buf)
+{
+ struct pps_s *dev = class_get_devdata(cdev);
+
+ return sprintf(buf, "%ld.%09ld#%ld\n",
+ dev->assert_tu.tspec.tv_sec,
+ dev->assert_tu.tspec.tv_nsec,
+ dev->assert_sequence);
+}
+
+static ssize_t pps_show_clear(struct class_device *cdev, char *buf)
+{
+ struct pps_s *dev = class_get_devdata(cdev);
+
+ return sprintf(buf, "%ld.%09ld#%ld\n",
+ dev->clear_tu.tspec.tv_sec,
+ dev->clear_tu.tspec.tv_nsec,
+ dev->clear_sequence);
+}
+
+static ssize_t pps_show_mode(struct class_device *cdev, char *buf)
+{
+ struct pps_source_info_s *info = to_pps_info(cdev);
+
+ return sprintf(buf, "%4x\n", info->mode);
+}
+
+static ssize_t pps_show_echo(struct class_device *cdev, char *buf)
+{
+ struct pps_source_info_s *info = to_pps_info(cdev);
+
+ return sprintf(buf, "%d\n", !!info->echo);
+}
+
+static ssize_t pps_show_name(struct class_device *cdev, char *buf)
+{
+ struct pps_source_info_s *info = to_pps_info(cdev);
+
+ return sprintf(buf, "%s\n", info->name);
+}
+
+static ssize_t pps_show_path(struct class_device *cdev, char *buf)
+{
+ struct pps_source_info_s *info = to_pps_info(cdev);
+
+ return sprintf(buf, "%s\n", info->path);
+}
+
+/*
+ * Files definitions
+ */
+
+#define DECLARE_INFO_ATTR(_name, _mode, _show, _store) \
+{ \
+ .attr = { \
+ .name = __stringify(_name), \
+ .mode = _mode, \
+ .owner = THIS_MODULE, \
+ }, \
+ .show = _show, \
+ .store = _store, \
+}
+
+static struct class_device_attribute pps_class_device_attributes[] = {
+ DECLARE_INFO_ATTR(assert, 0444, pps_show_assert, NULL),
+ DECLARE_INFO_ATTR(clear, 0444, pps_show_clear, NULL),
+ DECLARE_INFO_ATTR(mode, 0444, pps_show_mode, NULL),
+ DECLARE_INFO_ATTR(echo, 0444, pps_show_echo, NULL),
+ DECLARE_INFO_ATTR(name, 0444, pps_show_name, NULL),
+ DECLARE_INFO_ATTR(path, 0444, pps_show_path, NULL),
+};
+
+/*
+ * Class definitions
+ */
+
+static void pps_class_release(struct class_device *cdev)
+{
+ /* Nop??? */
+}
+
+static struct class pps_class = {
+ .name = "pps",
+ .release = pps_class_release,
+};
+
+/*
+ * Public functions
+ */
+
+void pps_sysfs_remove_source_entry(struct pps_source_info_s *info)
+{
+ int i;
+
+ /* Sanity checks */
+ if (info == NULL)
+ return;
+
+ /* Delete info files */
+ if (info->mode&PPS_CAPTUREASSERT)
+ class_device_remove_file(&info->class_dev,
+ &pps_class_device_attributes[0]);
+
+ if (info->mode&PPS_CAPTURECLEAR)
+ class_device_remove_file(&info->class_dev,
+ &pps_class_device_attributes[1]);
+
+ for (i = 2; i < ARRAY_SIZE(pps_class_device_attributes); i++)
+ class_device_remove_file(&info->class_dev,
+ &pps_class_device_attributes[i]);
+
+ /* Deregister the pps class */
+ class_device_unregister(&info->class_dev);
+}
+
+int pps_sysfs_create_source_entry(struct pps_source_info_s *info, int id)
+{
+ char buf[32];
+ int i, ret;
+
+ /* Sanity checks */
+ if (info == NULL || id >= PPS_MAX_SOURCES)
+ return -EINVAL;
+
+ /* Create dir class device name */
+ sprintf(buf, "%.02d", id);
+
+ /* Setup the class struct */
+ memset(&info->class_dev, 0, sizeof(struct class_device));
+ info->class_dev.class = &pps_class;
+ strlcpy(info->class_dev.class_id, buf, KOBJ_NAME_LEN);
+ class_set_devdata(&info->class_dev, &pps_source[id]);
+
+ /* Register the new class */
+ ret = class_device_register(&info->class_dev);
+ if (unlikely(ret))
+ goto error_class_device_register;
+
+ /* Create info files */
+
+ /* Create file "assert" and "clear" according to source capability */
+ if (info->mode & PPS_CAPTUREASSERT) {
+ ret = class_device_create_file(&info->class_dev,
+ &pps_class_device_attributes[0]);
+ i = 0;
+ if (unlikely(ret))
+ goto error_class_device_create_file;
+ }
+ if (info->mode & PPS_CAPTURECLEAR) {
+ ret = class_device_create_file(&info->class_dev,
+ &pps_class_device_attributes[1]);
+ i = 1;
+ if (unlikely(ret))
+ goto error_class_device_create_file;
+ }
+
+ for (i = 2; i < ARRAY_SIZE(pps_class_device_attributes); i++) {
+ ret = class_device_create_file(&info->class_dev,
+ &pps_class_device_attributes[i]);
+ if (unlikely(ret))
+ goto error_class_device_create_file;
+ }
+
+ return 0;
+
+error_class_device_create_file:
+ while (--i >= 0)
+ class_device_remove_file(&info->class_dev,
+ &pps_class_device_attributes[i]);
+
+ class_device_unregister(&info->class_dev);
+ /* Here the release() method was already called */
+
+error_class_device_register:
+
+ return ret;
+}
+
+void pps_sysfs_unregister(void)
+{
+ class_unregister(&pps_class);
+}
+
+int pps_sysfs_register(void)
+{
+ return class_register(&pps_class);
+}
diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index 48e259a..3e6ed91 100644
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -2101,6 +2101,8 @@ 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 326020f..4a9906f 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 +634,52 @@ 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;
+
+ 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,
+ -1 /* PPS ID is up to the system */);
+ if (ret < 0) {
+ pps_err("cannot register PPS source \"%s\"", state->pps_info.path);
+ return ret;
+ }
+ port->pps_source = ret;
+ pps_info("PPS source #%d \"%s\" added to the system ",
+ 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(&state->pps_info);
+ pps_dbg("PPS source #%d \"%s\" removed from the system",
+ 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 +854,19 @@ 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,
@@ -2100,6 +2155,12 @@ 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;
@@ -2349,6 +2410,12 @@ 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/netlink.h b/include/linux/netlink.h
index 2e23353..9d55343 100644
--- a/include/linux/netlink.h
+++ b/include/linux/netlink.h
@@ -24,6 +24,7 @@
/* leave room for NETLINK_DM (DM Events) */
#define NETLINK_SCSITRANSPORT 18 /* SCSI Transports */
#define NETLINK_ECRYPTFS 19
+#define NETLINK_PPSAPI 20 /* linuxPPS support */
#define MAX_LINKS 32
diff --git a/include/linux/parport.h b/include/linux/parport.h
index 9cdd694..f53d9f4 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 <asm/system.h>
#include <asm/ptrace.h>
#include <asm/semaphore.h>
@@ -327,6 +328,11 @@ struct parport {
struct list_head full_list;
struct parport *slaves[3];
+
+#ifdef CONFIG_PPS_CLIENT_LP
+ struct pps_source_info_s pps_info;
+ int pps_source; /* PPS source ID */
+#endif
};
#define DEFAULT_SPIN_TIME 500 /* us */
@@ -517,6 +523,12 @@ 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(int irq, struct parport *port)
{
+#ifdef CONFIG_PPS_CLIENT_LP
+ pps_event(port->pps_source, PPS_CAPTUREASSERT, port);
+ pps_dbg("parport_pc: PPS assert event at %lu on source #%d",
+ jiffies, port->pps_source);
+#endif
+
parport_ieee1284_interrupt (irq, port);
read_lock(&port->cad_lock);
if (port->cad && port->cad->irq_func)
diff --git a/include/linux/pps.h b/include/linux/pps.h
new file mode 100644
index 0000000..e40ac70
--- /dev/null
+++ b/include/linux/pps.h
@@ -0,0 +1,229 @@
+/*
+ * pps.h -- PPS API kernel header.
+ *
+ *
+ * Copyright (C) 2005-2007 Rodolfo Giometti <giometti@xxxxxxxx>
+ *
+ * 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 <asm/types.h>
+#include <sys/socket.h>
+#include <sys/time.h>
+#endif
+#include <linux/netlink.h>
+
+#define PPS_API_VERS_2 2 /* LinuxPPS proposal, dated 2006-05 */
+#define PPS_API_VERS PPS_API_VERS_2
+#define LINUXPSS_API 1 /* mark LinuxPPS API */
+
+#define PPS_MAX_NAME_LEN 32
+
+typedef unsigned long pps_seq_t; /* sequence number */
+
+typedef struct ntp_fp {
+ unsigned int integral;
+ unsigned int fractional;
+} ntp_fp_t; /* NTP-compatible time stamp */
+
+typedef union pps_timeu {
+ struct timespec tspec;
+ ntp_fp_t ntpfp;
+ unsigned long longpad[3];
+} pps_timeu_t; /* generic data type to represent time stamps */
+
+typedef struct pps_info {
+ pps_seq_t assert_sequence; /* seq. num. of assert event */
+ pps_seq_t clear_sequence; /* seq. num. of clear event */
+ pps_timeu_t assert_tu; /* time of assert event */
+ pps_timeu_t clear_tu; /* time of clear event */
+ int current_mode; /* current mode bits */
+} pps_info_t;
+
+typedef struct pps_params {
+ int api_version; /* API version # */
+ int mode; /* mode bits */
+ pps_timeu_t assert_off_tu; /* offset compensation for assert */
+ pps_timeu_t clear_off_tu; /* offset compensation for clear */
+} pps_params_t;
+
+/*
+ * 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_netlink_msg {
+ int cmd; /* the command to execute */
+ int source;
+ char name[PPS_MAX_NAME_LEN]; /* symbolic name */
+ char path[PPS_MAX_NAME_LEN]; /* path of the connected device */
+ int consumer; /* selected kernel consumer */
+ pps_params_t params;
+ int mode; /* edge */
+ int tsformat; /* format of time stamps */
+ pps_info_t info;
+ struct timespec timeout;
+ int ret;
+};
+#define PPSAPI_MAX_PAYLOAD sizeof(struct pps_netlink_msg)
+
+#define PPS_CREATE 1
+#define PPS_DESTROY 2
+#define PPS_SETPARMS 3
+#define PPS_GETPARMS 4
+#define PPS_GETCAP 5
+#define PPS_FETCH 6
+#define PPS_KC_BIND 7
+#define PPS_FIND_SRC 8
+#define PPS_FIND_PATH 9
+
+#ifdef __KERNEL__
+
+#include <linux/socket.h>
+#include <net/sock.h>
+
+/*
+ * Misc macros
+ */
+
+#define PPS_VERSION "3.2.0"
+
+#ifdef CONFIG_PPS_DEBUG
+#define pps_dbg(format, arg...) printk(KERN_DEBUG "%s: " format "\n" , \
+ KBUILD_MODNAME , ## arg)
+#else
+#define dbg(format, arg...) do {} while (0)
+#endif
+
+#define pps_err(format, arg...) printk(KERN_ERR "%s: " format "\n" , \
+ KBUILD_MODNAME , ## arg)
+#define pps_info(format, arg...) printk(KERN_INFO "%s: " format "\n" , \
+ KBUILD_MODNAME , ## arg)
+
+/*
+ * Global defines
+ */
+
+#define PPS_MAX_SOURCES 16
+
+/* The specific PPS source info */
+struct pps_source_info_s {
+ 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);/* the PPS echo function */
+
+ /* sysfs section */
+ struct class_device class_dev;
+};
+
+/* The main struct */
+struct pps_s {
+ struct pps_source_info_s *info; /* PSS source info */
+
+ pps_params_t params; /* PPS's current params */
+
+ volatile pps_seq_t assert_sequence; /* PPS' assert event seq # */
+ volatile pps_seq_t clear_sequence; /* PPS' clear event seq # */
+ volatile pps_timeu_t assert_tu;
+ volatile pps_timeu_t clear_tu;
+ int current_mode; /* PPS mode at event time */
+
+ int go; /* PPS event is arrived? */
+ wait_queue_head_t queue; /* PPS event queue */
+};
+
+/*
+ * Global variables
+ */
+
+extern struct pps_s pps_source[PPS_MAX_SOURCES];
+extern spinlock_t pps_lock;
+
+/*
+ * Global functions
+ */
+
+static inline int pps_is_allocated(int source)
+{
+ return pps_source[source].info != NULL;
+}
+
+#define to_pps_info(obj) container_of((obj), struct pps_source_info_s, class_dev)
+
+/*
+ * Exported functions
+ */
+
+extern int pps_register_source(struct pps_source_info_s *info,
+ int default_params, int try_id);
+extern void pps_unregister_source(struct pps_source_info_s *info);
+extern void pps_event(int source, int event, void *data);
+
+extern int pps_sysfs_create_source_entry(struct pps_source_info_s *info,
+ int id);
+extern void pps_sysfs_remove_source_entry(struct pps_source_info_s *info);
+extern int pps_sysfs_register(void);
+extern void pps_sysfs_unregister(void);
+
+#endif /* __KERNEL__ */
+
+#endif /* _PPS_H_ */
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index aa2653a..01a6547 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -148,6 +148,7 @@
#include <linux/sched.h>
#include <linux/tty.h>
#include <linux/mutex.h>
+#include <linux/pps.h>
struct uart_port;
struct uart_info;
@@ -227,6 +228,9 @@ 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)
@@ -271,7 +275,8 @@ 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 */
@@ -303,6 +308,10 @@ struct uart_state {
struct uart_info *info;
struct uart_port *port;
+#ifdef CONFIG_PPS_CLIENT_UART
+ struct pps_source_info_s pps_info;
+#endif
+
struct mutex mutex;
};
@@ -467,13 +476,23 @@ 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);
+ pps_dbg("serial8250: PPS assert event at %lu on source #%d",
+ jiffies, port->pps_source);
+ }
+ else {
+ pps_event(port->pps_source, PPS_CAPTURECLEAR, port);
+ pps_dbg("serial8250: PPS clear event at %lu on source #%d",
+ jiffies, port->pps_source);
+ }
+ }
#endif
+ port->icount.dcd++;
+
if (info->flags & UIF_CHECK_CD) {
if (status)
wake_up_interruptible(&info->open_wait);