diff --git a/Documentation/pps.txt b/Documentation/pps.txt new file mode 100644 index 0000000..a00b9d0 --- /dev/null +++ b/Documentation/pps.txt @@ -0,0 +1,206 @@ + + PPS - Pulse Per Second + ---------------------- + +(C) Copyright 2007 Rodolfo Giometti + + +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 who +provides an high and precise signal each second so that an application +can use it to adjust time clock. + +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 +usefull beside(!) 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 +linuxpps_source_info_s as follow: + + static struct linuxpps_source_info_s linuxpps_ktimer_info = { + name : "ktimer", + path : "", + mode : PPS_CAPTUREASSERT|PPS_OFFSETASSERT|PPS_ECHOASSERT| \ + PPS_CANWAIT|PPS_TSFMT_TSPEC, + echo : linuxpps_ktimer_echo, + }; + +and then calling the function linuxpps_register_source() in your +intialization routine as follow: + + source = linuxpps_register_source(&linuxpps_ktimer_info, + PPS_CAPTUREASSERT|PPS_OFFSETASSERT, + -1 /* is up to the system */); + +The linuxpps_register_source() prototype is: + + int linuxpps_register_source(struct linuxpps_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 +linuxpps_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: + + linuxpps_event(source, PPS_CAPTUREASSERT, ptr); + +The same function may also run the defined echo function +(linuxpps_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. + + +PROCFS support +-------------- + +If PROCFS support is enabled a new directory "/proc/pps" is created: + + $ ls /proc/pps/ + 00 01 sources + +The file "sources" holds a brief description of all PPS sources +defined in the system: + + $ cat /proc/pps/sources + id mode echo name path + ---- ------ ---- ---------------- ---------------- + 00 1133 no serial0 /dev/ttyS0 + 01 1133 no serial1 /dev/ttyS1 + +The other entries are directories that hold one or two files according +to the ability of the associated source to provide "assert" and +"clear" timestamps: + + $ ls /proc/pps/00 + assert clear + +Inside each "assert" and "clear" file you can find the timestamp and a +sequence number: + + $ cat /proc/pps/00/assert + 1170026870.983207967 #8 + + +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 + +Files "assert" and "clear" have the same functionality as their PROCFS +counterparts but with different syntax due to the one-value-per-file +sysfs pragma. Other files are: + +* echo: reports if the PPS source has an echo function or not; + +* mode: reports available PPS functioning modes (in the same form as + PROCFS does); + +* 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). + + +Resources +--------- + +Wiki: http://wiki.enneenne.com/index.php/LinuxPPS_support and the LinuxPPS +ML: http://ml.enneenne.com/cgi-bin/mailman/listinfo/linuxpps. 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 3a718f5..d0007f7 100644 --- a/drivers/Makefile +++ b/drivers/Makefile @@ -59,6 +59,7 @@ obj-$(CONFIG_INPUT) += input/ obj-$(CONFIG_I2O) += message/ obj-$(CONFIG_RTC_LIB) += rtc/ obj-$(CONFIG_I2C) += 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 b51d08b..6185679 100644 --- a/drivers/char/lp.c +++ b/drivers/char/lp.c @@ -750,6 +750,27 @@ static struct console lpcons = { #endif /* console on line printer */ +/* --- support for PPS signal on the line printer -------------- */ + +#ifdef CONFIG_PPS_CLIENT_LP + +static inline void lp_pps_echo(int source, int event, void *data) +{ + struct parport *port = (struct parport *) 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 }; @@ -821,6 +842,36 @@ static int lp_register(int nr, struct parport *port) } #endif +#ifdef CONFIG_PPS_CLIENT_LP + snprintf(port->pps_info.path, LINUXPPS_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, LINUXPPS_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 = linuxpps_register_source(&(port->pps_info), + PPS_CAPTUREASSERT | PPS_OFFSETASSERT, + -1 /* is up to the system */); + if (port->pps_source < 0) + err("cannot register PPS source \"%s\"", + port->pps_info.path); + else + info("PPS source #%d \"%s\" added to the system", + port->pps_source, port->pps_info.path); + } + else { + port->pps_source = -1; + err("PPS support disabled due port \"%s\" is in polling mode", + port->pps_info.path); + } +#endif + return 0; } @@ -864,6 +915,14 @@ static void lp_detach (struct parport *port) console_registered = NULL; } #endif /* CONFIG_LP_CONSOLE */ + +#ifdef CONFIG_PPS_CLIENT_LP + if (port->pps_source >= 0) { + linuxpps_unregister_source(&(port->pps_info)); + 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/parport/parport_pc.c b/drivers/parport/parport_pc.c index b61c17b..426b0ac 100644 --- a/drivers/parport/parport_pc.c +++ b/drivers/parport/parport_pc.c @@ -272,6 +272,14 @@ static int clear_epp_timeout(struct parport *pb) static irqreturn_t parport_pc_interrupt(int irq, void *dev_id) { +#ifdef CONFIG_PPS_CLIENT_LP_PARPORT_PC + struct parport *p = (struct parport *) dev_id; + + linuxpps_event(p->pps_source, PPS_CAPTUREASSERT, p); + dbg("parport_pc: PPS assert event at %lu on source #%d", + jiffies, p->pps_source); +#endif + parport_generic_irq(irq, (struct parport *) dev_id); /* FIXME! Was it really ours? */ return IRQ_HANDLED; diff --git a/drivers/pps/Kconfig b/drivers/pps/Kconfig new file mode 100644 index 0000000..20aa5f0 --- /dev/null +++ b/drivers/pps/Kconfig @@ -0,0 +1,43 @@ +# +# 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_PROCFS + bool "PPS procfs support" + depends on PPS + default y + help + Say Y here if you want the PPS support to produce a new file into + the "/proc" directory which holds useful information regarding + registered PPS clients into the system. + +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..cc51203 --- /dev/null +++ b/drivers/pps/Makefile @@ -0,0 +1,7 @@ +# +# Makefile for the PPS core. +# + +pps_core-objs += pps.o kapi.o sysfs.o procfs.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..4214b52 --- /dev/null +++ b/drivers/pps/clients/Kconfig @@ -0,0 +1,56 @@ +# +# 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 && ( PPS = m && SERIAL_CORE = y ) + +config PPS_CLIENT_UART + bool "UART serial support" + depends on SERIAL_CORE && ! ( PPS = m && SERIAL_CORE = y ) + +comment "8250 serial support (forced off)" + depends on PPS_CLIENT_UART && SERIAL_8250 && \ + ( PPS = m && SERIAL_8250 = y ) + +config PPS_CLIENT_UART_8250 + bool "8250 serial support" + depends on PPS_CLIENT_UART && SERIAL_8250 && \ + ! ( PPS = m && SERIAL_8250 = y ) + help + If you say yes here you get support for a PPS source connected + with the CD (Carrier Detect) pin of your 8250 serial line chip. + +comment "Parallel printer support (forced off)" + depends on PRINTER && ( PPS = m && PRINTER = y ) + +config PPS_CLIENT_LP + bool "Parallel printer support" + depends on PRINTER && ! ( PPS = m && PRINTER = y ) + +comment "Parport PC support (forced off)" + depends on PPS_CLIENT_LP && PARPORT_PC && \ + ( PPS = m && PARPORT_PC = y ) + +config PPS_CLIENT_LP_PARPORT_PC + bool "Parport PC support" + depends on PPS_CLIENT_LP && PARPORT_PC && \ + ! ( PPS = m && PARPORT_PC = y ) + help + If you say yes here you get support for a PPS source connected + with the interrupt pin of your PC 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..e0f6989 --- /dev/null +++ b/drivers/pps/clients/ktimer.c @@ -0,0 +1,107 @@ +/* + * ktimer.c -- kernel timer test client + * + * + * Copyright (C) 2005-2006 Rodolfo Giometti + * + * 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 +#include +#include +#include +#include + +#include +#include + +/* --- Global variables ----------------------------------------------------- */ + +static int source; +static struct timer_list ktimer; + +/* --- The kernel timer ----------------------------------------------------- */ + +static void linuxpps_ktimer_event(unsigned long ptr) { + info("PPS event at %lu", jiffies); + + linuxpps_event(source, PPS_CAPTUREASSERT, NULL); + + /* Rescheduling */ + ktimer.expires = jiffies+HZ; /* 1 second */ + add_timer(&ktimer); +} + +/* --- The echo function ---------------------------------------------------- */ + +static void linuxpps_ktimer_echo(int source, int event, void *data) +{ + info("echo %s %s for source %d", + event&PPS_CAPTUREASSERT ? "assert" : "", + event&PPS_CAPTURECLEAR ? "clear" : "", + source); +} + +/* --- The PPS info struct -------------------------------------------------- */ + +static struct linuxpps_source_info_s linuxpps_ktimer_info = { + name : "ktimer", + path : "", + mode : PPS_CAPTUREASSERT|PPS_OFFSETASSERT|PPS_ECHOASSERT| \ + PPS_CANWAIT|PPS_TSFMT_TSPEC, + echo : linuxpps_ktimer_echo, +}; + +/* --- Module staff -------------------------------------------------------- */ + +static void __exit linuxpps_ktimer_exit(void) +{ + del_timer_sync(&ktimer); + linuxpps_unregister_source(&linuxpps_ktimer_info); + + info("ktimer PPS source unregistered"); +} + +static int __init linuxpps_ktimer_init(void) +{ + int ret; + + ret = linuxpps_register_source(&linuxpps_ktimer_info, + PPS_CAPTUREASSERT|PPS_OFFSETASSERT, + -1 /* is up to the system */); + if (ret < 0) { + err("cannot register ktimer source"); + return ret; + } + source = ret; + + init_timer(&ktimer); + ktimer.function = linuxpps_ktimer_event; + ktimer.expires = jiffies+HZ; /* 1 second */ + add_timer(&ktimer); + + info("ktimer PPS source registered at %d", source); + + return 0; +} + +module_init(linuxpps_ktimer_init); +module_exit(linuxpps_ktimer_exit); + +MODULE_AUTHOR("Rodolfo Giometti "); +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..f4b0b6e --- /dev/null +++ b/drivers/pps/kapi.c @@ -0,0 +1,213 @@ +/* + * kapi.c -- kernel API + * + * + * Copyright (C) 2005-2007 Rodolfo Giometti + * + * 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 +#include +#include +#include + +#include +#include + +/* --- Local functions ----------------------------------------------------- */ + +#ifndef NSEC_PER_SEC +#define NSEC_PER_SEC 1000000000 +#endif +static void linuxpps_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 inline int __linuxpps_register_source(struct linuxpps_source_info_s *info, int default_params, int try_id) +{ + int i; + + if (try_id >= 0) { + if (__linuxpps_is_allocated(try_id)) { + err("source id %d busy", try_id); + return -EBUSY; + } + i = try_id; + } + else { + for (i = 0; i < LINUXPPS_MAX_SOURCES; i++) + if (!__linuxpps_is_allocated(i)) + break; + if (i >= LINUXPPS_MAX_SOURCES) { + err("no free source ids"); + return -ENOMEM; + } + } + + /* Sanity checks */ + if ((info->mode&default_params) != default_params) { + err("unsupported default parameters"); + return -EINVAL; + } + if ((info->mode&(PPS_ECHOASSERT|PPS_ECHOCLEAR)) != 0 && info->echo == NULL) { + err("echo function is not defined"); + return -EINVAL; + } + if ((info->mode&(PPS_TSFMT_TSPEC|PPS_TSFMT_NTPFP)) == 0) { + err("unspecified time format"); + return -EINVAL; + } + + /* Allocate the PPS source */ + memset(&linuxpps_source[i], 0, sizeof(struct linuxpps_s)); + linuxpps_source[i].info = info; + linuxpps_source[i].params.api_version = PPS_API_VERS; + linuxpps_source[i].params.mode = default_params; + init_waitqueue_head(&linuxpps_source[i].queue); + + return i; +} + +int linuxpps_register_source(struct linuxpps_source_info_s *info, int default_params, int try_id) +{ + unsigned long flags; + int i, ret; + + spin_lock_irqsave(&linuxpps_lock, flags); + ret = __linuxpps_register_source(info, default_params, try_id); + spin_unlock_irqrestore(&linuxpps_lock, flags); + + if (ret < 0) + return ret; + i = ret; + + ret = linuxpps_sysfs_create_source_entry(info, i); + if (ret < 0) + err("unable to create sysfs entry for source %d", i); + + ret = linuxpps_procfs_create_source_entry(info, i); + if (ret < 0) + err("unable to create procfs entry for source %d", i); + + return i; +} + +static inline int __linuxpps_unregister_source(struct linuxpps_source_info_s *info) +{ + int i; + + for (i = 0; i < LINUXPPS_MAX_SOURCES; i++) + if (__linuxpps_is_allocated(i) && linuxpps_source[i].info == info) + break; + + if (i >= LINUXPPS_MAX_SOURCES) { + err("warning! Try to unregister an unknow PPS source"); + return -EINVAL; + } + + /* Deallocate the PPS source */ + linuxpps_source[i].info = NULL; + + return i; +} + +void linuxpps_unregister_source(struct linuxpps_source_info_s *info) +{ + unsigned long flags; + int i, ret; + + spin_lock_irqsave(&linuxpps_lock, flags); + ret = __linuxpps_unregister_source(info); + spin_unlock_irqrestore(&linuxpps_lock, flags); + + if (ret < 0) + return; + i = ret; + + linuxpps_sysfs_remove_source_entry(info, i); + linuxpps_procfs_remove_source_entry(info, i); +} + +void linuxpps_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 (!linuxpps_is_allocated(source)) { + err("unknow source for event!"); + return; + } + if ((event&(PPS_CAPTUREASSERT|PPS_CAPTURECLEAR)) == 0 ) { + err("unknow event (%x) for source %d", event, source); + return; + } + + /* Must call the echo function? */ + if ((linuxpps_source[source].params.mode&(PPS_ECHOASSERT|PPS_ECHOCLEAR)) != 0) + linuxpps_source[source].info->echo(source, event, data); + + /* Check the event */ + linuxpps_source[source].current_mode = linuxpps_source[source].params.mode; + if (event&PPS_CAPTUREASSERT) { + /* We have to add an offset? */ + if (linuxpps_source[source].params.mode&PPS_OFFSETASSERT) + linuxpps_add_offset(&ts, &linuxpps_source[source].params.assert_off_tu.tspec); + + /* Save the time stamp */ + linuxpps_source[source].assert_tu.tspec = ts; + linuxpps_source[source].assert_sequence++; + dbg("capture assert seq #%lu for source %d", + linuxpps_source[source].assert_sequence, source); + } + if (event&PPS_CAPTURECLEAR) { + /* We have to add an offset? */ + if (linuxpps_source[source].params.mode&PPS_OFFSETCLEAR) + linuxpps_add_offset(&ts, &linuxpps_source[source].params.clear_off_tu.tspec); + + /* Save the time stamp */ + linuxpps_source[source].clear_tu.tspec = ts; + linuxpps_source[source].clear_sequence++; + dbg("capture clear seq #%lu for source %d", + linuxpps_source[source].clear_sequence, source); + } + + wake_up_interruptible(&linuxpps_source[source].queue); +} + +/* --- Exported functions -------------------------------------------------- */ + +EXPORT_SYMBOL(linuxpps_register_source); +EXPORT_SYMBOL(linuxpps_unregister_source); +EXPORT_SYMBOL(linuxpps_event); diff --git a/drivers/pps/pps.c b/drivers/pps/pps.c new file mode 100644 index 0000000..b3c677f --- /dev/null +++ b/drivers/pps/pps.c @@ -0,0 +1,377 @@ +/* + * main.c -- Main driver file + * + * + * Copyright (C) 2005-2007 Rodolfo Giometti + * + * 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 +#include +#include +#include +#include + +#include +#include + +/* --- Global variables ---------------------------------------------------- */ + +struct linuxpps_s linuxpps_source[LINUXPPS_MAX_SOURCES]; +spinlock_t linuxpps_lock = SPIN_LOCK_UNLOCKED; + +/* --- Local variables ----------------------------------------------------- */ + +static struct sock *nl_sk = NULL; + +/* --- Misc functions ------------------------------------------------------ */ + +static inline int linuxpps_find_source(int source) +{ + int i; + + if (source >= 0) { + if (source >= LINUXPPS_MAX_SOURCES || !linuxpps_is_allocated(source)) + return -EINVAL; + else + return source; + } + + for (i = 0; i < LINUXPPS_MAX_SOURCES; i++) + if (linuxpps_is_allocated(i)) + break; + + if (i >= LINUXPPS_MAX_SOURCES) + return -EINVAL; + + return i; +} + +static inline int linuxpps_find_path(char *path) +{ + int i; + + for (i = 0; i < LINUXPPS_MAX_SOURCES; i++) + if (linuxpps_is_allocated(i) && + (strncmp(linuxpps_source[i].info->path, path, + LINUXPPS_MAX_NAME_LEN) == 0 || + strncmp(linuxpps_source[i].info->name, path, + LINUXPPS_MAX_NAME_LEN) == 0)) + break; + + if (i >= LINUXPPS_MAX_SOURCES) + return -EINVAL; + + return i; +} + +/* --- Input function ------------------------------------------------------ */ + +static void linuxpps_nl_data_ready(struct sock *sk, int len) +{ + struct sk_buff *skb; + struct nlmsghdr *nlh; + struct pps_netlink_msg *nlpps; + + int cmd, source, id; + wait_queue_head_t *queue; + unsigned long timeout; + + int ret; + + while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) { + nlh = (struct nlmsghdr *) skb->data; + 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 : { + dbg("PPS_CREATE: source %d", source); + + /* Check if the requested source is allocated */ + ret = linuxpps_find_source(source); + if (ret < 0) { + nlpps->ret = ret; + break; + } + + nlpps->source = ret; + nlpps->ret = 0; + + break; + } + + case PPS_DESTROY : { + dbg("PPS_DESTROY: source %d", source); + + /* Nothing to do here! Just answer ok... */ + nlpps->ret = 0; + + break; + } + + case PPS_SETPARMS : { + dbg("PPS_SETPARMS: source %d", source); + + /* Check the capabilities */ + if (!capable(CAP_SYS_TIME)) { + nlpps->ret = -EPERM; + break; + } + + /* Sanity checks */ + if (nlpps->source < 0 || !linuxpps_is_allocated(source)) { + nlpps->ret = -EINVAL; + break; + } + if ((nlpps->params.mode&~linuxpps_source[source].info->mode) != 0) { + dbg("unsupported capabilities"); + nlpps->ret = -EINVAL; + break; + } + if ((nlpps->params.mode&(PPS_CAPTUREASSERT|PPS_CAPTURECLEAR)) == 0) { + 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 */ + dbg("time format unspecified"); + nlpps->params.mode |= PPS_TSFMT_TSPEC; + } + + /* Save the new parameters */ + linuxpps_source[source].params = nlpps->params; + + /* Restore the read only parameters */ + if (linuxpps_source[source].info->mode&PPS_CANWAIT) + linuxpps_source[source].params.mode |= PPS_CANWAIT; + linuxpps_source[source].params.api_version = PPS_API_VERS; + + nlpps->ret = 0; + + break; + } + + case PPS_GETPARMS : { + dbg("PPS_GETPARMS: source %d", source); + + /* Sanity checks */ + if (nlpps->source < 0 || !linuxpps_is_allocated(source)) { + nlpps->ret = -EINVAL; + break; + } + + nlpps->params = linuxpps_source[source].params; + nlpps->ret = 0; + + break; + } + + case PPS_GETCAP : { + dbg("PPS_GETCAP: source %d", source); + + /* Sanity checks */ + if (nlpps->source < 0 || !linuxpps_is_allocated(source)) { + nlpps->ret = -EINVAL; + break; + } + + nlpps->mode = linuxpps_source[source].info->mode; + nlpps->ret = 0; + + break; + } + + case PPS_FETCH : { + dbg("PPS_FETCH: source %d", source); + queue = &linuxpps_source[source].queue; + + /* Sanity checks */ + if (nlpps->source < 0 || !linuxpps_is_allocated(source)) { + nlpps->ret = -EINVAL; + break; + } + if ((nlpps->tsformat != PPS_TSFMT_TSPEC) != 0 ) { + dbg("unsupported time format"); + nlpps->ret = -EINVAL; + break; + } + + /* Manage the timeout */ + if (nlpps->timeout.tv_sec != -1) { + timeout = nlpps->timeout.tv_sec*HZ; + timeout += nlpps->timeout.tv_nsec/(1000000000/HZ); + + if (timeout != 0) { + timeout = interruptible_sleep_on_timeout(queue, timeout); + if (timeout <= 0) { + dbg("timeout expired"); + nlpps->ret = -ETIMEDOUT; + break; + } + } + } + else + interruptible_sleep_on(queue); + + /* Return the fetched timestamp */ + nlpps->info.assert_sequence = linuxpps_source[source].assert_sequence; + nlpps->info.clear_sequence = linuxpps_source[source].clear_sequence; + nlpps->info.assert_tu = linuxpps_source[source].assert_tu; + nlpps->info.clear_tu = linuxpps_source[source].clear_tu; + nlpps->info.current_mode = linuxpps_source[source].current_mode; + + nlpps->ret = 0; + + break; + } + + case PPS_KC_BIND : { + dbg("PPS_KC_BIND: source %d", source); + /* Feature currently not supported */ + nlpps->ret = -EOPNOTSUPP; + + break; + } + + case PPS_FIND_SRC : { + dbg("PPS_FIND_SRC: source %d", source); + source = linuxpps_find_source(source); + if (source < 0) { + dbg("no PPS devices found"); + nlpps->ret = -ENODEV; + break; + } + + /* Found! So copy the info */ + nlpps->source = source; + strncpy(nlpps->name, linuxpps_source[source].info->name, + LINUXPPS_MAX_NAME_LEN); + strncpy(nlpps->path, linuxpps_source[source].info->path, + LINUXPPS_MAX_NAME_LEN); + nlpps->ret = 0; + + break; + } + + case PPS_FIND_PATH : { + dbg("PPS_FIND_PATH: source %s", nlpps->path); + source = linuxpps_find_path(nlpps->path); + if (source < 0) { + dbg("no PPS devices found"); + nlpps->ret = -ENODEV; + break; + } + + /* Found! So copy the info */ + nlpps->source = source; + strncpy(nlpps->name, linuxpps_source[source].info->name, + LINUXPPS_MAX_NAME_LEN); + strncpy(nlpps->path, linuxpps_source[source].info->path, + LINUXPPS_MAX_NAME_LEN); + nlpps->ret = 0; + + break; + } + + default : { + /* Unknow command */ + dbg("unknow command %d", nlpps->cmd); + + nlpps->ret = -EINVAL; + } + } + + /* Send an answer to the userland */ + id = NETLINK_CB(skb).pid; + 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); + dbg("... reply sent (%d)", ret); + } +} + +/* --- Module staff -------------------------------------------------------- */ + +static void __exit linuxpps_exit(void) +{ + linuxpps_sysfs_unregister(); + linuxpps_procfs_unregister(); + sock_release(nl_sk->sk_socket); + + info("LinuxPPS API ver. %d removed", PPS_API_VERS); +} + +static int __init linuxpps_init(void) +{ + int ret; + + nl_sk = netlink_kernel_create(NETLINK_PPSAPI, 0, + linuxpps_nl_data_ready, THIS_MODULE); + if (nl_sk == NULL) { + err("unable to create netlink kernel socket"); + return -EBUSY; + } + dbg("netlink protocol %d created", NETLINK_PPSAPI); + + /* Init the main struct */ + memset(linuxpps_source, 0, sizeof(struct linuxpps_s)*LINUXPPS_MAX_SOURCES); + + /* Register to sysfs */ + ret = linuxpps_sysfs_register(); + if (ret < 0) { + err("unable to register sysfs"); + goto linuxpps_sysfs_register_error; + } + + /* Register to procfs */ + ret = linuxpps_procfs_register(); + if (ret < 0) { + err("unable to register procfs"); + goto linuxpps_procfs_register_error; + } + + info("LinuxPPS API ver. %d registered", PPS_API_VERS); + info("Software ver. %s - Copyright 2005-2007 Rodolfo Giometti ", PPS_VERSION); + + return 0; + +linuxpps_procfs_register_error : + + linuxpps_sysfs_unregister(); + +linuxpps_sysfs_register_error : + + sock_release(nl_sk->sk_socket); + + return ret; +} + +subsys_initcall(linuxpps_init); +module_exit(linuxpps_exit); + +MODULE_AUTHOR("Rodolfo Giometti "); +MODULE_DESCRIPTION("LinuxPPS support (RFC 2783) - ver. " PPS_VERSION); +MODULE_LICENSE("GPL"); diff --git a/drivers/pps/procfs.c b/drivers/pps/procfs.c new file mode 100644 index 0000000..929d9d7 --- /dev/null +++ b/drivers/pps/procfs.c @@ -0,0 +1,179 @@ +/* + * procfs.c -- procfs support + * + * + * Copyright (C) 2005-2007 Rodolfo Giometti + * + * 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 +#include +#include + +#include +#include + +#ifdef CONFIG_PPS_PROCFS + +static struct proc_dir_entry *procfs_root_dir; + +/* ----- Private functions -------------------------------------------- */ + +static int linuxpps_procfs_assert_read(char *page, char **start, off_t off, int count, int *eof, void *data) +{ + int len = 0; + int id = (int) data; + len += sprintf(page+len, "%ld.%09ld #%ld\n", + linuxpps_source[id].assert_tu.tspec.tv_sec, + linuxpps_source[id].assert_tu.tspec.tv_nsec, + linuxpps_source[id].assert_sequence); + + *eof = 1; + return len; +} + +static int linuxpps_procfs_clear_read(char *page, char **start, off_t off, int count, int *eof, void *data) +{ + int len = 0; + int id = (int) data; + len += sprintf(page+len, "%ld.%09ld #%ld\n", + linuxpps_source[id].clear_tu.tspec.tv_sec, + linuxpps_source[id].clear_tu.tspec.tv_nsec, + linuxpps_source[id].clear_sequence); + + *eof = 1; + return len; +} + +static int linuxpps_sources_read(char *page, char **start, off_t off, int count, int *eof, void *data) +{ + int i; + int len = 0; + + len += sprintf(page+len, "id\tmode\techo\tname\t\t\tpath\n"); + len += sprintf(page+len, "----\t------\t----\t----------------\t----------------\n"); + for (i = 0; i < LINUXPPS_MAX_SOURCES; i++) + if (linuxpps_is_allocated(i)) + len += sprintf(page+len, "%.02d\t%4x\t%s\t%s\t\t%s\n", + i, + linuxpps_source[i].info->mode, + linuxpps_source[i].info->echo ? "yes" : "no", + linuxpps_source[i].info->name, + linuxpps_source[i].info->path); + + *eof = 1; + return len; +} + +/* ----- Public functions --------------------------------------------- */ + +void linuxpps_procfs_remove_source_entry(struct linuxpps_source_info_s *info, int id) { + char buf[32]; + + /* Sanity checks */ + if (info == NULL || info->dir == NULL || id >= LINUXPPS_MAX_SOURCES) + return; + + remove_proc_entry("clear", info->dir); + remove_proc_entry("assert", info->dir); + sprintf(buf, "%.02d", id); + remove_proc_entry(buf, procfs_root_dir); +} + +int linuxpps_procfs_create_source_entry(struct linuxpps_source_info_s *info, int id) { + struct proc_dir_entry *procfs_file; + char buf[32]; + + /* Sanity checks */ + if (info == NULL || id >= LINUXPPS_MAX_SOURCES) + return -EINVAL; + + /* Create dir "/proc/pps/" */ + sprintf(buf, "%.02d", id); + info->dir = proc_mkdir(buf, procfs_root_dir); + if (info->dir == NULL) + return -ENOMEM; + + /* Create file "assert" and "clear" according to source capability */ + if (info->mode&PPS_CAPTUREASSERT) { + procfs_file = create_proc_entry("assert", S_IRUGO|S_IWUSR, info->dir); + if (procfs_file == NULL) + goto exit; + procfs_file->read_proc = linuxpps_procfs_assert_read; + procfs_file->data = (void *) id; + } + if (info->mode&PPS_CAPTURECLEAR) { + procfs_file = create_proc_entry("clear", S_IRUGO|S_IWUSR, info->dir); + if (procfs_file == NULL) + goto exit; + procfs_file->read_proc = linuxpps_procfs_clear_read; + procfs_file->data = (void *) id; + } + + return 0; + +exit : + linuxpps_procfs_remove_source_entry(info, id); + + return -ENOMEM; +} + +void linuxpps_procfs_unregister(void) +{ + remove_proc_entry("pps/sources", NULL); + + /* The root dir in /proc/pps */ + remove_proc_entry("pps", NULL); +} + +int linuxpps_procfs_register(void) +{ + struct proc_dir_entry *procfs_file; + + /* The root dir in /proc */ + procfs_root_dir = proc_mkdir("pps", NULL); + if (procfs_root_dir == NULL) + return -ENOMEM; + + /* The file "sources" */ + procfs_file = create_proc_entry("sources", S_IRUGO|S_IWUSR, procfs_root_dir); + if (procfs_file == NULL) { + linuxpps_procfs_unregister(); + return -ENOMEM; + } + procfs_file->owner = THIS_MODULE; + procfs_file->read_proc = linuxpps_sources_read; + procfs_file->write_proc = NULL; /* no write method */ + + info("procfs enabled"); + return 0; +} + +#else /* CONFIG_PPS_PROCFS */ + +void linuxpps_procfs_unregister(void) +{ + /* Nothing to do here... */ + return; +} + +int linuxpps_procfs_register(void) +{ + info("procfs not enabled"); + return 0; +} +#endif /* CONFIG_PPS_PROCFS */ diff --git a/drivers/pps/sysfs.c b/drivers/pps/sysfs.c new file mode 100644 index 0000000..6cd01f5 --- /dev/null +++ b/drivers/pps/sysfs.c @@ -0,0 +1,200 @@ +/* + * sysfs.c -- sysfs support + * + * + * Copyright (C) 2007 Rodolfo Giometti + * + * 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 +#include +#include + +#include +#include + +/* ----- Private functions -------------------------------------------- */ + +static ssize_t linuxpps_show_assert(struct class_device *cdev, char *buf) +{ + struct linuxpps_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 linuxpps_show_clear(struct class_device *cdev, char *buf) +{ + struct linuxpps_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 linuxpps_show_mode(struct class_device *cdev, char *buf) +{ + struct linuxpps_source_info_s *info = to_pps_info(cdev); + + return sprintf(buf, "%4x\n", info->mode); +} + +static ssize_t linuxpps_show_echo(struct class_device *cdev, char *buf) +{ + struct linuxpps_source_info_s *info = to_pps_info(cdev); + + return sprintf(buf, "%d\n", !!info->echo); +} + +static ssize_t linuxpps_show_name(struct class_device *cdev, char *buf) +{ + struct linuxpps_source_info_s *info = to_pps_info(cdev); + + return sprintf(buf, "%s\n", info->name); +} + +static ssize_t linuxpps_show_path(struct class_device *cdev, char *buf) +{ + struct linuxpps_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 linuxpps_class_device_attributes[] = { + DECLARE_INFO_ATTR(assert, 0644, linuxpps_show_assert, NULL), + DECLARE_INFO_ATTR(clear, 0644, linuxpps_show_clear, NULL), + DECLARE_INFO_ATTR(mode, 0644, linuxpps_show_mode, NULL), + DECLARE_INFO_ATTR(echo, 0644, linuxpps_show_echo, NULL), + DECLARE_INFO_ATTR(name, 0644, linuxpps_show_name, NULL), + DECLARE_INFO_ATTR(path, 0644, linuxpps_show_path, NULL), +}; + +/* ----- Class definitions -------------------------------------------- */ + +static void linuxpps_class_release(struct class_device *cdev) +{ + /* Nop??? */ +} + +static struct class linuxpps_class = { + .name = "pps", + .release = linuxpps_class_release, +}; + +/* ----- Public functions --------------------------------------------- */ + +void linuxpps_sysfs_remove_source_entry(struct linuxpps_source_info_s *info, int id) { + int i; + + /* Sanity checks */ + if (info == NULL || info->dir == NULL || id >= LINUXPPS_MAX_SOURCES) + return; + + for (i = 0; i < ARRAY_SIZE(linuxpps_class_device_attributes); i++) + class_device_remove_file(&info->class_dev, + &linuxpps_class_device_attributes[i]); + + class_device_unregister(&info->class_dev); +} + +int linuxpps_sysfs_create_source_entry(struct linuxpps_source_info_s *info, int id) { + char buf[32]; + int i, ret; + + /* Sanity checks */ + if (info == NULL || id >= LINUXPPS_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 = &linuxpps_class; + strlcpy(info->class_dev.class_id, buf, KOBJ_NAME_LEN); + class_set_devdata(&info->class_dev, &linuxpps_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, + &linuxpps_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, + &linuxpps_class_device_attributes[1]); + i = 1; + if (unlikely(ret)) + goto error_class_device_create_file; + } + + for (i = 2; i < ARRAY_SIZE(linuxpps_class_device_attributes); i++) { + ret = class_device_create_file(&info->class_dev, + &linuxpps_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, + &linuxpps_class_device_attributes[i]); + + class_device_unregister(&info->class_dev); + /* Here the release() method was already called */ + +error_class_device_register : + + return ret; +} + +void linuxpps_sysfs_unregister(void) +{ + class_unregister(&linuxpps_class); +} + +int linuxpps_sysfs_register(void) +{ + return class_register(&linuxpps_class); +} diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c index 98ec861..cd9a003 100644 --- a/drivers/serial/8250.c +++ b/drivers/serial/8250.c @@ -1315,8 +1315,25 @@ static unsigned int check_modem_status(struct uart_8250_port *up) up->port.icount.rng++; if (status & UART_MSR_DDSR) up->port.icount.dsr++; - if (status & UART_MSR_DDCD) + if (status & UART_MSR_DDCD) { +#ifdef CONFIG_PPS_CLIENT_UART_8250 + if (status & UART_MSR_DCD) { + linuxpps_event(up->port.pps_source, + PPS_CAPTUREASSERT, up); + dbg("serial8250: PPS assert event at %lu " + "on source #%d", + jiffies, up->port.pps_source); + } + else { + linuxpps_event(up->port.pps_source, + PPS_CAPTURECLEAR, up); + dbg("serial8250: PPS clear event at %lu " + "on source #%d", + jiffies, up->port.pps_source); + } +#endif uart_handle_dcd_change(&up->port, status & UART_MSR_DCD); + } if (status & UART_MSR_DCTS) uart_handle_cts_change(&up->port, status & UART_MSR_CTS); @@ -2004,6 +2021,9 @@ 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; +#ifdef CONFIG_PPS_CLIENT_UART_8250 + up->ier |= UART_IER_MSI; /* enable interrupts */ +#endif serial_out(up, UART_IER, up->ier); @@ -2718,6 +2738,7 @@ void serial8250_unregister_port(int line) struct uart_8250_port *uart = &serial8250_ports[line]; mutex_lock(&serial_mutex); + uart_remove_one_port(&serial8250_reg, &uart->port); if (serial8250_isa_devs) { uart->port.flags &= ~UPF_BOOT_AUTOCONF; diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c index 0422c0f..a11faa0 100644 --- a/drivers/serial/serial_core.c +++ b/drivers/serial/serial_core.c @@ -37,6 +37,11 @@ #include #include +#ifdef CONFIG_PPS_CLIENT_UART +#include +#include +#endif + #undef DEBUG #ifdef DEBUG #define DPRINTK(x...) printk(x) @@ -2083,6 +2088,7 @@ uart_configure_port(struct uart_driver *drv, struct uart_state *state, struct uart_port *port) { unsigned int flags; + int retval; /* * If there isn't a port here, don't do anything further. @@ -2124,6 +2130,33 @@ uart_configure_port(struct uart_driver *drv, struct uart_state *state, */ if (!uart_console(port)) uart_change_pm(state, 3); + +#ifdef CONFIG_PPS_CLIENT_UART + /* + * Add the PPS support for the probed port. + */ + snprintf(state->pps_info.name, LINUXPPS_MAX_NAME_LEN, + "%s%d", drv->driver_name, port->line); + snprintf(state->pps_info.path, LINUXPPS_MAX_NAME_LEN, + "/dev/%s%d", drv->dev_name, port->line); + + state->pps_info.mode = PPS_CAPTUREBOTH | \ + PPS_OFFSETASSERT | PPS_OFFSETCLEAR | \ + PPS_CANWAIT | PPS_TSFMT_TSPEC; + + retval = linuxpps_register_source(&state->pps_info, + PPS_CAPTUREBOTH | \ + PPS_OFFSETASSERT | PPS_OFFSETCLEAR, + -1 /* PPS ID is up to the system */); + if (retval < 0) { + err("cannot register PPS source \"%s\"", + state->pps_info.path); + return; + } + port->pps_source = retval; + info("PPS source #%d \"%s\" added to the system ", + port->pps_source, state->pps_info.path); +#endif } } @@ -2350,6 +2383,16 @@ int uart_remove_one_port(struct uart_driver *drv, struct uart_port *port) port->flags |= UPF_DEAD; mutex_unlock(&state->mutex); +#ifdef CONFIG_PPS_CLIENT_UART + /* + * Remove the PPS support. + */ + if (port->type != PORT_UNKNOWN) { + linuxpps_unregister_source(&state->pps_info); + dbg("PPS source #%d \"%s\" removed from the system", + port->pps_source, state->pps_info.path); + } +#endif /* * Remove the devices from the tty layer */ diff --git a/include/linux/netlink.h b/include/linux/netlink.h index 2a20f48..32eee60 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -21,7 +21,7 @@ #define NETLINK_DNRTMSG 14 /* DECnet routing messages */ #define NETLINK_KOBJECT_UEVENT 15 /* Kernel messages to userspace */ #define NETLINK_GENERIC 16 -/* leave room for NETLINK_DM (DM Events) */ +#define NETLINK_PPSAPI 17 /* linuxPPS support */ #define NETLINK_SCSITRANSPORT 18 /* SCSI Transports */ #define NETLINK_ECRYPTFS 19 diff --git a/include/linux/parport.h b/include/linux/parport.h index 80682aa..d225362 100644 --- a/include/linux/parport.h +++ b/include/linux/parport.h @@ -104,6 +104,11 @@ typedef enum { #include #include +#ifdef CONFIG_PPS_CLIENT_LP_PARPORT_PC +#include +#include +#endif + /* Define this later. */ struct parport; struct pardevice; @@ -323,6 +328,11 @@ struct parport { struct list_head full_list; struct parport *slaves[3]; + +#ifdef CONFIG_PPS_CLIENT_LP_PARPORT_PC + struct linuxpps_source_info_s pps_info; + int pps_source; /* PPS source ID */ +#endif }; #define DEFAULT_SPIN_TIME 500 /* us */ diff --git a/include/linux/pps.h b/include/linux/pps.h new file mode 100644 index 0000000..52f67ce --- /dev/null +++ b/include/linux/pps.h @@ -0,0 +1,119 @@ +/* + * pps.h -- PPS API kernel header. + * + * + * Copyright (C) 2005-2007 Rodolfo Giometti + * + * 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_ + +/* ----- Misc macros -------------------------------------------------- */ + +#define PPS_VERSION "2.4.3" + +#ifdef CONFIG_PPS_DEBUG +#define dbg(format, arg...) printk(KERN_DEBUG "%s: " format "\n" , \ + KBUILD_MODNAME , ## arg) +#else +#define dbg(format, arg...) do {} while (0) +#endif + +#define err(format, arg...) printk(KERN_ERR "%s: " format "\n" , \ + KBUILD_MODNAME , ## arg) +#define info(format, arg...) printk(KERN_INFO "%s: " format "\n" , \ + KBUILD_MODNAME , ## arg) + +/* --- Global defines ------------------------------------------------------ */ + +#define LINUXPPS_MAX_SOURCES 16 + +/* --- Global variables ---------------------------------------------------- */ + +/* The specific PPS source info */ +struct linuxpps_source_info_s { + char name[LINUXPPS_MAX_NAME_LEN]; /* simbolic name */ + char path[LINUXPPS_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; + + /* procfs section */ + struct proc_dir_entry *dir; +}; + +/* The main struct */ +struct linuxpps_s { + struct linuxpps_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 */ + + wait_queue_head_t queue; /* PPS event queue */ +}; + +/* --- Global variables ---------------------------------------------------- */ + +extern struct linuxpps_s linuxpps_source[LINUXPPS_MAX_SOURCES]; +extern spinlock_t linuxpps_lock; + +/* --- Global functions ---------------------------------------------------- */ + +static inline int __linuxpps_is_allocated(int source) { + return linuxpps_source[source].info != NULL; +} + +static inline int linuxpps_is_allocated(int source) { + unsigned long flags; + int ret; + + spin_lock_irqsave(&linuxpps_lock, flags); + ret = __linuxpps_is_allocated(source); + spin_unlock_irqrestore(&linuxpps_lock, flags); + + return ret; +} + +#define to_class_dev(obj) container_of((obj), struct class_device, kobj) +#define to_pps_info(obj) container_of((obj), struct linuxpps_source_info_s, class_dev) + +/* --- Exported functions -------------------------------------------------- */ + +extern int linuxpps_register_source(struct linuxpps_source_info_s *info, int default_params, int try_id); +extern void linuxpps_unregister_source(struct linuxpps_source_info_s *info); +extern void linuxpps_event(int source, int event, void *data); + +extern int linuxpps_procfs_create_source_entry(struct linuxpps_source_info_s *info, int id); +extern void linuxpps_procfs_remove_source_entry(struct linuxpps_source_info_s *info, int id); +extern int linuxpps_procfs_register(void); +extern void linuxpps_procfs_unregister(void); + +extern int linuxpps_sysfs_create_source_entry(struct linuxpps_source_info_s *info, int id); +extern void linuxpps_sysfs_remove_source_entry(struct linuxpps_source_info_s *info, int id); +extern int linuxpps_sysfs_register(void); +extern void linuxpps_sysfs_unregister(void); + +#endif /* _PPS_H_ */ diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index 586aaba..645f8e1 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -145,6 +145,11 @@ #include #include +#ifdef CONFIG_PPS_CLIENT_UART +#include +#include +#endif + struct uart_port; struct uart_info; struct serial_struct; @@ -223,6 +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) @@ -295,6 +303,10 @@ struct uart_state { struct uart_info *info; struct uart_port *port; +#ifdef CONFIG_PPS_CLIENT_UART + struct linuxpps_source_info_s pps_info; +#endif + struct mutex mutex; }; diff --git a/include/linux/timepps.h b/include/linux/timepps.h new file mode 100644 index 0000000..5bf400a --- /dev/null +++ b/include/linux/timepps.h @@ -0,0 +1,514 @@ +/* + * timepps.h -- PPS API main header + * + * + * Copyright (C) 2005-2007 Rodolfo Giometti + * + * 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. + * + * NOTE: this file is *strongly* based on a previous job by Ulrich Windl. + * The original copyright note follows: + * + * Interface to the PPS API described in RFC 2783 (March 2000) + * + * Copyright (c) 1999, 2001, 2004 by Ulrich Windl, + * based on code by Reg Clemens + * based on code by Poul-Henning Kamp + * + * ---------------------------------------------------------------------- + * "THE BEER-WARE LICENSE" (Revision 42): + * wrote this file. As long as you retain this notice + * you can do whatever you want with this stuff. If we meet some day, and + * you think this stuff is worth it, you can buy me a beer in return. + * Poul-Henning Kamp + * ---------------------------------------------------------------------- + */ + +#ifndef _SYS_TIMEPPS_H_ +#define _SYS_TIMEPPS_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 --------------------------------------------- */ + +#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 NETLINK_PPSAPI 17 /* we use just one free number... */ + +typedef struct pps_handle_s { + int source; + int socket; +} pps_handle_t; /* represents a PPS source */ + +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; + +#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 + +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; + +#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 + +/* --- 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 /* "This bit is 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! ----------------------- */ + +#define LINUXPPS_MAX_NAME_LEN 32 +struct pps_netlink_msg { + int cmd; /* the command to execute */ + int source; + char name[LINUXPPS_MAX_NAME_LEN]; /* symbolic name */ + char path[LINUXPPS_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) + +/* check Documentation/ioctl-number.txt! */ +#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 +#include +#include + +struct pps_state { + pps_params_t parm; /* PPS parameters */ + pps_info_t info; /* PPS information */ + int cap; /* PPS capabilities */ + long ecount; /* interpolation offset of event */ + struct timespec etime; /* kernel time of event */ + wait_queue_head_t ewait; /* wait queue for event */ +}; + +/* State variables to bind kernel consumer */ +/* PPS API (RFC 2783): current source and mode for ``kernel consumer'' */ +extern const struct pps *pps_kc_hardpps_dev; /* some unique pointer to device */ +extern int pps_kc_hardpps_mode; /* mode bits for kernel consumer */ + +/* Return allowed mode bits for given pps struct, file's mode, and user. + * Bits set in `*obligatory' must be set. Returned bits may be set. */ +extern int pps_allowed_mode(const struct pps *pps, mode_t fmode, int *obligatory); + +#else /* !__KERNEL__ */ + +/* --- 3.4 Functions ------------------------------------------------------- */ + +#include +#include +#include +#include +#include + +/* Private functions */ + +static int netlink_msg(int socket, struct pps_netlink_msg *nlpps) +{ + struct sockaddr_nl dest_addr; + struct nlmsghdr *nlh; + struct iovec iov; + struct msghdr msg; + + int ret; + + memset(&msg, 0, sizeof(msg)); + + /* Create the destination address */ + memset(&dest_addr, 0, sizeof(dest_addr)); + dest_addr.nl_family = AF_NETLINK; + dest_addr.nl_pid = 0; /* for the kernel */ + dest_addr.nl_groups = 0; /* not in mcast groups */ + + nlh = (struct nlmsghdr *) alloca(NLMSG_SPACE(PPSAPI_MAX_PAYLOAD)); + if (nlh == NULL) + return -1; + + /* Fill the netlink message header */ + nlh->nlmsg_len = NLMSG_SPACE(PPSAPI_MAX_PAYLOAD); + nlh->nlmsg_pid = getpid(); + nlh->nlmsg_flags = 0; + memcpy(NLMSG_DATA(nlh), nlpps, sizeof(struct pps_netlink_msg)); + + iov.iov_base = (void *) nlh; + iov.iov_len = nlh->nlmsg_len; + msg.msg_name = (void *) &dest_addr; + msg.msg_namelen = sizeof(dest_addr); + msg.msg_iov = &iov; + msg.msg_iovlen = 1; + + /* Send the message */ + ret = sendmsg(socket, &msg, 0); + if (ret < 0) + return ret; + + /* Wait for the answer */ + memset(nlh, 0, NLMSG_SPACE(PPSAPI_MAX_PAYLOAD)); + ret = recvmsg(socket, &msg, 0); + if (ret < 0) + return ret; + + /* Check the return value */ + memcpy(nlpps, NLMSG_DATA(nlh), sizeof(struct pps_netlink_msg)); + if (nlpps->ret < 0) { + errno = -nlpps->ret; + return -1; + } + + return 0; +} + +/* The PPSAPI functions */ + +/* Create PPS handle from source number */ +static __inline int time_pps_create(int source, pps_handle_t *handle) +{ + struct sockaddr_nl src_addr, dest_addr; + struct pps_netlink_msg nlpps; + + int ret; + + /* Create the netlink socket */ + ret = socket(PF_NETLINK, SOCK_RAW, NETLINK_PPSAPI); + if (ret < 0) + return ret; + handle->socket = ret; + + /* Bind the socket with the source address */ + memset(&src_addr, 0, sizeof(src_addr)); + src_addr.nl_family = AF_NETLINK; + src_addr.nl_pid = 0; /* ask kernel to choose an unique ID */ + src_addr.nl_groups = 0; /* not in mcast groups */ + ret = bind(handle->socket, (struct sockaddr *) &src_addr, sizeof(src_addr)); + if (ret < 0) { + close(handle->socket); + return ret; + } + + /* Now ask the kernel to create the PPS source */ + nlpps.cmd = PPS_CREATE; + nlpps.source = source; + ret = netlink_msg(handle->socket, &nlpps); + if (ret < 0) + return ret; + + /* Save the PPS source returned by the kernel */ + handle->source = nlpps.source; + + return 0; +} + +/* Release PPS handle */ +static __inline int time_pps_destroy(pps_handle_t handle) +{ + struct pps_netlink_msg nlpps; + + int ret; + + /* Ask the kernel to destroy the PPS source */ + nlpps.cmd = PPS_DESTROY; + nlpps.source = handle.source; + ret = netlink_msg(handle.socket, &nlpps); + if (ret < 0) + return ret; + + /* Now we can destroy the netlink socket */ + close(handle.socket); + + return 0; +} + +/* Set parameters for handle */ +static __inline int time_pps_setparams(pps_handle_t handle, const pps_params_t *ppsparams) +{ + struct pps_netlink_msg nlpps; + + int ret; + + /* Ask the kernel to set the new PPS source's parameters */ + nlpps.cmd = PPS_SETPARMS; + nlpps.source = handle.source; + nlpps.params = *ppsparams; + ret = netlink_msg(handle.socket, &nlpps); + if (ret < 0) + return ret; + + return 0; +} + +static __inline int time_pps_getparams(pps_handle_t handle, pps_params_t *ppsparams) +{ + struct pps_netlink_msg nlpps; + + int ret; + + /* Ask the kernel to return the PPS source's parameters */ + nlpps.cmd = PPS_GETPARMS; + nlpps.source = handle.source; + ret = netlink_msg(handle.socket, &nlpps); + if (ret < 0) + return ret; + + /* Return the parameters */ + *ppsparams = nlpps.params; + + return 0; +} + +/* Get capabilities for handle */ +static __inline int time_pps_getcap(pps_handle_t handle, int *mode) +{ + struct pps_netlink_msg nlpps; + + int ret; + + /* Ask the kernel to return the PPS source's capabilities */ + nlpps.cmd = PPS_GETCAP; + nlpps.source = handle.source; + ret = netlink_msg(handle.socket, &nlpps); + if (ret < 0) + return ret; + + /* Return the capabilities */ + *mode = nlpps.mode; + + return 0; +} + +/* current event for handle */ +static __inline int time_pps_fetch(pps_handle_t handle, const int tsformat, pps_info_t *ppsinfobuf, const struct timespec *timeout) +{ + struct pps_netlink_msg nlpps; + + int ret; + + /* Ask the kernel to return the PPS source's capabilities */ + nlpps.cmd = PPS_FETCH; + nlpps.source = handle.source; + nlpps.tsformat = tsformat; + if (timeout) + nlpps.timeout = *timeout; + else /* wait forever */ + nlpps.timeout.tv_sec = nlpps.timeout.tv_nsec = -1; + + ret = netlink_msg(handle.socket, &nlpps); + if (ret < 0) + return ret; + + /* Return the timestamps */ + *ppsinfobuf = nlpps.info; + + return 0; +} + +/* Specify kernel consumer */ +static __inline int time_pps_kcbind(pps_handle_t handle, const int kernel_consumer, const int edge, const int tsformat) +{ + struct pps_netlink_msg nlpps; + + int ret; + + /* Ask the kernel to destroy the PPS source */ + nlpps.cmd = PPS_KC_BIND; + nlpps.source = handle.source; + nlpps.consumer = kernel_consumer; + nlpps.mode = edge; + nlpps.tsformat = tsformat; + ret = netlink_msg(handle.socket, &nlpps); + if (ret < 0) + return ret; + + return 0; +} + +/* Find a PPS source */ +#define PPS_HAVE_FINDSOURCE 1 +static __inline int time_pps_findsource(int index, char *path, int pathlen, char *idstring, int idlen) +{ + int sock; + struct sockaddr_nl src_addr, dest_addr; + struct pps_netlink_msg nlpps; + + int ret; + + /* Create the netlink socket */ + ret = socket(PF_NETLINK, SOCK_RAW, NETLINK_PPSAPI); + if (ret < 0) + return ret; + sock = ret; + + /* Bind the socket with the source address */ + memset(&src_addr, 0, sizeof(src_addr)); + src_addr.nl_family = AF_NETLINK; + src_addr.nl_pid = 0; /* ask kernel to choose an unique ID */ + src_addr.nl_groups = 0; /* not in mcast groups */ + ret = bind(sock, (struct sockaddr *) &src_addr, sizeof(src_addr)); + if (ret < 0) { + close(sock); + return ret; + } + + /* Ask the kernel to destroy the PPS source */ + nlpps.cmd = PPS_FIND_SRC; + nlpps.source = index; + ret = netlink_msg(sock, &nlpps); + if (ret < 0) { + close(sock); + return ret; + } + + strncpy(path, nlpps.path, pathlen); + strncpy(idstring, nlpps.name, idlen); + + close(sock); + return nlpps.source; +} + +#define PPS_HAVE_FINDPATH 1 +static __inline void time_pps_readlink(char *link, int linklen, char *path, int pathlen) +{ + int i; + + i = readlink(link, path, pathlen-1); + if (i <= 0) { + /* "link" is not a valid symbolic so we directly use it */ + strncpy(path, link, linklen <= pathlen ? linklen : pathlen); + return; + } + + /* Return the file name where "link" points to */ + path[i] = '\0'; + return; +} + +static __inline int time_pps_findpath(char *path, int pathlen, char *idstring, int idlen) +{ + int sock; + struct sockaddr_nl src_addr, dest_addr; + struct pps_netlink_msg nlpps; + + int ret; + + /* Create the netlink socket */ + ret = socket(PF_NETLINK, SOCK_RAW, NETLINK_PPSAPI); + if (ret < 0) + return ret; + sock = ret; + + /* Bind the socket with the source address */ + memset(&src_addr, 0, sizeof(src_addr)); + src_addr.nl_family = AF_NETLINK; + src_addr.nl_pid = 0; /* ask kernel to choose an unique ID */ + src_addr.nl_groups = 0; /* not in mcast groups */ + ret = bind(sock, (struct sockaddr *) &src_addr, sizeof(src_addr)); + if (ret < 0) { + close(sock); + return ret; + } + + /* Ask the kernel to destroy the PPS source */ + nlpps.cmd = PPS_FIND_PATH; + strncpy(nlpps.path, path, pathlen); + ret = netlink_msg(sock, &nlpps); + if (ret < 0) { + close(sock); + return ret; + } + + strncpy(path, nlpps.path, pathlen); + strncpy(idstring, nlpps.name, idlen); + + close(sock); + return nlpps.source; +} + +#endif /* !__KERNEL__ */ +#endif /* _SYS_TIMEPPS_H_ */