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-rw-r--r--drivers/pps/Kconfig45
-rw-r--r--drivers/pps/Makefile11
-rw-r--r--drivers/pps/clients/Kconfig37
-rw-r--r--drivers/pps/clients/Makefile11
-rw-r--r--drivers/pps/clients/pps-gpio.c255
-rw-r--r--drivers/pps/clients/pps-ktimer.c87
-rw-r--r--drivers/pps/clients/pps-ldisc.c141
-rw-r--r--drivers/pps/clients/pps_parport.c225
-rw-r--r--drivers/pps/generators/Kconfig14
-rw-r--r--drivers/pps/generators/Makefile10
-rw-r--r--drivers/pps/generators/pps_gen_parport.c241
-rw-r--r--drivers/pps/kapi.c223
-rw-r--r--drivers/pps/kc.c109
-rw-r--r--drivers/pps/kc.h33
-rw-r--r--drivers/pps/pps.c489
-rw-r--r--drivers/pps/sysfs.c99
16 files changed, 2030 insertions, 0 deletions
diff --git a/drivers/pps/Kconfig b/drivers/pps/Kconfig
new file mode 100644
index 0000000000..e1651d51cf
--- /dev/null
+++ b/drivers/pps/Kconfig
@@ -0,0 +1,45 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# PPS support configuration
+#
+
+menuconfig PPS
+ tristate "PPS support"
+ help
+ PPS (Pulse Per Second) is a special pulse provided by some GPS
+ antennae. Userland can use it to get a high-precision time
+ reference.
+
+ Some antennae's PPS signals are connected with the CD (Carrier
+ Detect) pin of the serial line they use to communicate with the
+ host. In this case use the SERIAL_LINE client support.
+
+ Some antennae's PPS signals are connected with some special host
+ inputs so you have to enable the corresponding client support.
+
+ To compile this driver as a module, choose M here: the module
+ will be called pps_core.ko.
+
+if PPS
+
+config PPS_DEBUG
+ bool "PPS debugging messages"
+ 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.
+
+config NTP_PPS
+ bool "PPS kernel consumer support"
+ depends on !NO_HZ_COMMON
+ help
+ This option adds support for direct in-kernel time
+ synchronization using an external PPS signal.
+
+ It doesn't work on tickless systems at the moment.
+
+source "drivers/pps/clients/Kconfig"
+
+source "drivers/pps/generators/Kconfig"
+
+endif # PPS
diff --git a/drivers/pps/Makefile b/drivers/pps/Makefile
new file mode 100644
index 0000000000..ceaf65cc1f
--- /dev/null
+++ b/drivers/pps/Makefile
@@ -0,0 +1,11 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Makefile for the PPS core.
+#
+
+pps_core-y := pps.o kapi.o sysfs.o
+pps_core-$(CONFIG_NTP_PPS) += kc.o
+obj-$(CONFIG_PPS) := pps_core.o
+obj-y += clients/ generators/
+
+ccflags-$(CONFIG_PPS_DEBUG) := -DDEBUG
diff --git a/drivers/pps/clients/Kconfig b/drivers/pps/clients/Kconfig
new file mode 100644
index 0000000000..4f3244e17a
--- /dev/null
+++ b/drivers/pps/clients/Kconfig
@@ -0,0 +1,37 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# PPS clients configuration
+#
+
+comment "PPS clients support"
+
+config PPS_CLIENT_KTIMER
+ tristate "Kernel timer client (Testing client, use for debug)"
+ help
+ If you say yes here you get support for a PPS debugging client
+ which uses a kernel timer to generate the PPS signal.
+
+ This driver can also be built as a module. If so, the module
+ will be called pps-ktimer.
+
+config PPS_CLIENT_LDISC
+ tristate "PPS line discipline"
+ depends on TTY
+ help
+ If you say yes here you get support for a PPS source connected
+ with the CD (Carrier Detect) pin of your serial port.
+
+config PPS_CLIENT_PARPORT
+ tristate "Parallel port PPS client"
+ depends on PARPORT
+ help
+ If you say yes here you get support for a PPS source connected
+ with the interrupt pin of your parallel port.
+
+config PPS_CLIENT_GPIO
+ tristate "PPS client using GPIO"
+ help
+ If you say yes here you get support for a PPS source using
+ GPIO. To be useful you must also register a platform device
+ specifying the GPIO pin and other options, usually in your board
+ setup.
diff --git a/drivers/pps/clients/Makefile b/drivers/pps/clients/Makefile
new file mode 100644
index 0000000000..7a3807e578
--- /dev/null
+++ b/drivers/pps/clients/Makefile
@@ -0,0 +1,11 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Makefile for PPS clients.
+#
+
+obj-$(CONFIG_PPS_CLIENT_KTIMER) += pps-ktimer.o
+obj-$(CONFIG_PPS_CLIENT_LDISC) += pps-ldisc.o
+obj-$(CONFIG_PPS_CLIENT_PARPORT) += pps_parport.o
+obj-$(CONFIG_PPS_CLIENT_GPIO) += pps-gpio.o
+
+ccflags-$(CONFIG_PPS_DEBUG) := -DDEBUG
diff --git a/drivers/pps/clients/pps-gpio.c b/drivers/pps/clients/pps-gpio.c
new file mode 100644
index 0000000000..2f4b11b4df
--- /dev/null
+++ b/drivers/pps/clients/pps-gpio.c
@@ -0,0 +1,255 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * pps-gpio.c -- PPS client driver using GPIO
+ *
+ * Copyright (C) 2010 Ricardo Martins <rasm@fe.up.pt>
+ * Copyright (C) 2011 James Nuss <jamesnuss@nanometrics.ca>
+ */
+
+#define PPS_GPIO_NAME "pps-gpio"
+#define pr_fmt(fmt) PPS_GPIO_NAME ": " fmt
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/pps_kernel.h>
+#include <linux/gpio/consumer.h>
+#include <linux/list.h>
+#include <linux/property.h>
+#include <linux/timer.h>
+#include <linux/jiffies.h>
+
+/* Info for each registered platform device */
+struct pps_gpio_device_data {
+ int irq; /* IRQ used as PPS source */
+ struct pps_device *pps; /* PPS source device */
+ struct pps_source_info info; /* PPS source information */
+ struct gpio_desc *gpio_pin; /* GPIO port descriptors */
+ struct gpio_desc *echo_pin;
+ struct timer_list echo_timer; /* timer to reset echo active state */
+ bool assert_falling_edge;
+ bool capture_clear;
+ unsigned int echo_active_ms; /* PPS echo active duration */
+ unsigned long echo_timeout; /* timer timeout value in jiffies */
+};
+
+/*
+ * Report the PPS event
+ */
+
+static irqreturn_t pps_gpio_irq_handler(int irq, void *data)
+{
+ const struct pps_gpio_device_data *info;
+ struct pps_event_time ts;
+ int rising_edge;
+
+ /* Get the time stamp first */
+ pps_get_ts(&ts);
+
+ info = data;
+
+ rising_edge = gpiod_get_value(info->gpio_pin);
+ if ((rising_edge && !info->assert_falling_edge) ||
+ (!rising_edge && info->assert_falling_edge))
+ pps_event(info->pps, &ts, PPS_CAPTUREASSERT, data);
+ else if (info->capture_clear &&
+ ((rising_edge && info->assert_falling_edge) ||
+ (!rising_edge && !info->assert_falling_edge)))
+ pps_event(info->pps, &ts, PPS_CAPTURECLEAR, data);
+
+ return IRQ_HANDLED;
+}
+
+/* This function will only be called when an ECHO GPIO is defined */
+static void pps_gpio_echo(struct pps_device *pps, int event, void *data)
+{
+ /* add_timer() needs to write into info->echo_timer */
+ struct pps_gpio_device_data *info = data;
+
+ switch (event) {
+ case PPS_CAPTUREASSERT:
+ if (pps->params.mode & PPS_ECHOASSERT)
+ gpiod_set_value(info->echo_pin, 1);
+ break;
+
+ case PPS_CAPTURECLEAR:
+ if (pps->params.mode & PPS_ECHOCLEAR)
+ gpiod_set_value(info->echo_pin, 1);
+ break;
+ }
+
+ /* fire the timer */
+ if (info->pps->params.mode & (PPS_ECHOASSERT | PPS_ECHOCLEAR)) {
+ info->echo_timer.expires = jiffies + info->echo_timeout;
+ add_timer(&info->echo_timer);
+ }
+}
+
+/* Timer callback to reset the echo pin to the inactive state */
+static void pps_gpio_echo_timer_callback(struct timer_list *t)
+{
+ const struct pps_gpio_device_data *info;
+
+ info = from_timer(info, t, echo_timer);
+
+ gpiod_set_value(info->echo_pin, 0);
+}
+
+static int pps_gpio_setup(struct device *dev)
+{
+ struct pps_gpio_device_data *data = dev_get_drvdata(dev);
+ int ret;
+ u32 value;
+
+ data->gpio_pin = devm_gpiod_get(dev, NULL, GPIOD_IN);
+ if (IS_ERR(data->gpio_pin))
+ return dev_err_probe(dev, PTR_ERR(data->gpio_pin),
+ "failed to request PPS GPIO\n");
+
+ data->assert_falling_edge =
+ device_property_read_bool(dev, "assert-falling-edge");
+
+ data->echo_pin = devm_gpiod_get_optional(dev, "echo", GPIOD_OUT_LOW);
+ if (IS_ERR(data->echo_pin))
+ return dev_err_probe(dev, PTR_ERR(data->echo_pin),
+ "failed to request ECHO GPIO\n");
+
+ if (!data->echo_pin)
+ return 0;
+
+ ret = device_property_read_u32(dev, "echo-active-ms", &value);
+ if (ret) {
+ dev_err(dev, "failed to get echo-active-ms from FW\n");
+ return ret;
+ }
+
+ /* sanity check on echo_active_ms */
+ if (!value || value > 999) {
+ dev_err(dev, "echo-active-ms: %u - bad value from FW\n", value);
+ return -EINVAL;
+ }
+
+ data->echo_active_ms = value;
+
+ return 0;
+}
+
+static unsigned long
+get_irqf_trigger_flags(const struct pps_gpio_device_data *data)
+{
+ unsigned long flags = data->assert_falling_edge ?
+ IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING;
+
+ if (data->capture_clear) {
+ flags |= ((flags & IRQF_TRIGGER_RISING) ?
+ IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING);
+ }
+
+ return flags;
+}
+
+static int pps_gpio_probe(struct platform_device *pdev)
+{
+ struct pps_gpio_device_data *data;
+ struct device *dev = &pdev->dev;
+ int ret;
+ int pps_default_params;
+
+ /* allocate space for device info */
+ data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ dev_set_drvdata(dev, data);
+
+ /* GPIO setup */
+ ret = pps_gpio_setup(dev);
+ if (ret)
+ return ret;
+
+ /* IRQ setup */
+ ret = gpiod_to_irq(data->gpio_pin);
+ if (ret < 0) {
+ dev_err(dev, "failed to map GPIO to IRQ: %d\n", ret);
+ return -EINVAL;
+ }
+ data->irq = ret;
+
+ /* initialize PPS specific parts of the bookkeeping data structure. */
+ data->info.mode = PPS_CAPTUREASSERT | PPS_OFFSETASSERT |
+ PPS_ECHOASSERT | PPS_CANWAIT | PPS_TSFMT_TSPEC;
+ if (data->capture_clear)
+ data->info.mode |= PPS_CAPTURECLEAR | PPS_OFFSETCLEAR |
+ PPS_ECHOCLEAR;
+ data->info.owner = THIS_MODULE;
+ snprintf(data->info.name, PPS_MAX_NAME_LEN - 1, "%s.%d",
+ pdev->name, pdev->id);
+ if (data->echo_pin) {
+ data->info.echo = pps_gpio_echo;
+ data->echo_timeout = msecs_to_jiffies(data->echo_active_ms);
+ timer_setup(&data->echo_timer, pps_gpio_echo_timer_callback, 0);
+ }
+
+ /* register PPS source */
+ pps_default_params = PPS_CAPTUREASSERT | PPS_OFFSETASSERT;
+ if (data->capture_clear)
+ pps_default_params |= PPS_CAPTURECLEAR | PPS_OFFSETCLEAR;
+ data->pps = pps_register_source(&data->info, pps_default_params);
+ if (IS_ERR(data->pps)) {
+ dev_err(dev, "failed to register IRQ %d as PPS source\n",
+ data->irq);
+ return PTR_ERR(data->pps);
+ }
+
+ /* register IRQ interrupt handler */
+ ret = devm_request_irq(dev, data->irq, pps_gpio_irq_handler,
+ get_irqf_trigger_flags(data), data->info.name, data);
+ if (ret) {
+ pps_unregister_source(data->pps);
+ dev_err(dev, "failed to acquire IRQ %d\n", data->irq);
+ return -EINVAL;
+ }
+
+ dev_info(data->pps->dev, "Registered IRQ %d as PPS source\n",
+ data->irq);
+
+ return 0;
+}
+
+static int pps_gpio_remove(struct platform_device *pdev)
+{
+ struct pps_gpio_device_data *data = platform_get_drvdata(pdev);
+
+ pps_unregister_source(data->pps);
+ del_timer_sync(&data->echo_timer);
+ /* reset echo pin in any case */
+ gpiod_set_value(data->echo_pin, 0);
+ dev_info(&pdev->dev, "removed IRQ %d as PPS source\n", data->irq);
+ return 0;
+}
+
+static const struct of_device_id pps_gpio_dt_ids[] = {
+ { .compatible = "pps-gpio", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, pps_gpio_dt_ids);
+
+static struct platform_driver pps_gpio_driver = {
+ .probe = pps_gpio_probe,
+ .remove = pps_gpio_remove,
+ .driver = {
+ .name = PPS_GPIO_NAME,
+ .of_match_table = pps_gpio_dt_ids,
+ },
+};
+
+module_platform_driver(pps_gpio_driver);
+MODULE_AUTHOR("Ricardo Martins <rasm@fe.up.pt>");
+MODULE_AUTHOR("James Nuss <jamesnuss@nanometrics.ca>");
+MODULE_DESCRIPTION("Use GPIO pin as PPS source");
+MODULE_LICENSE("GPL");
+MODULE_VERSION("1.2.0");
diff --git a/drivers/pps/clients/pps-ktimer.c b/drivers/pps/clients/pps-ktimer.c
new file mode 100644
index 0000000000..d33106bd7a
--- /dev/null
+++ b/drivers/pps/clients/pps-ktimer.c
@@ -0,0 +1,87 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * pps-ktimer.c -- kernel timer test client
+ *
+ * Copyright (C) 2005-2006 Rodolfo Giometti <giometti@linux.it>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/time.h>
+#include <linux/timer.h>
+#include <linux/pps_kernel.h>
+
+/*
+ * Global variables
+ */
+
+static struct pps_device *pps;
+static struct timer_list ktimer;
+
+/*
+ * The kernel timer
+ */
+
+static void pps_ktimer_event(struct timer_list *unused)
+{
+ struct pps_event_time ts;
+
+ /* First of all we get the time stamp... */
+ pps_get_ts(&ts);
+
+ pps_event(pps, &ts, PPS_CAPTUREASSERT, NULL);
+
+ mod_timer(&ktimer, jiffies + HZ);
+}
+
+/*
+ * The PPS info struct
+ */
+
+static struct pps_source_info pps_ktimer_info = {
+ .name = "ktimer",
+ .path = "",
+ .mode = PPS_CAPTUREASSERT | PPS_OFFSETASSERT |
+ PPS_ECHOASSERT |
+ PPS_CANWAIT | PPS_TSFMT_TSPEC,
+ .owner = THIS_MODULE,
+};
+
+/*
+ * Module staff
+ */
+
+static void __exit pps_ktimer_exit(void)
+{
+ dev_info(pps->dev, "ktimer PPS source unregistered\n");
+
+ del_timer_sync(&ktimer);
+ pps_unregister_source(pps);
+}
+
+static int __init pps_ktimer_init(void)
+{
+ pps = pps_register_source(&pps_ktimer_info,
+ PPS_CAPTUREASSERT | PPS_OFFSETASSERT);
+ if (IS_ERR(pps)) {
+ pr_err("cannot register PPS source\n");
+ return PTR_ERR(pps);
+ }
+
+ timer_setup(&ktimer, pps_ktimer_event, 0);
+ mod_timer(&ktimer, jiffies + HZ);
+
+ dev_info(pps->dev, "ktimer PPS source registered\n");
+
+ return 0;
+}
+
+module_init(pps_ktimer_init);
+module_exit(pps_ktimer_exit);
+
+MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
+MODULE_DESCRIPTION("dummy PPS source by using a kernel timer (just for debug)");
+MODULE_LICENSE("GPL");
diff --git a/drivers/pps/clients/pps-ldisc.c b/drivers/pps/clients/pps-ldisc.c
new file mode 100644
index 0000000000..443d6bae19
--- /dev/null
+++ b/drivers/pps/clients/pps-ldisc.c
@@ -0,0 +1,141 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * pps-ldisc.c -- PPS line discipline
+ *
+ * Copyright (C) 2008 Rodolfo Giometti <giometti@linux.it>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/serial_core.h>
+#include <linux/tty.h>
+#include <linux/pps_kernel.h>
+#include <linux/bug.h>
+
+static void pps_tty_dcd_change(struct tty_struct *tty, bool active)
+{
+ struct pps_device *pps;
+ struct pps_event_time ts;
+
+ pps_get_ts(&ts);
+
+ pps = pps_lookup_dev(tty);
+ /*
+ * This should never fail, but the ldisc locking is very
+ * convoluted, so don't crash just in case.
+ */
+ if (WARN_ON_ONCE(pps == NULL))
+ return;
+
+ /* Now do the PPS event report */
+ pps_event(pps, &ts, active ? PPS_CAPTUREASSERT :
+ PPS_CAPTURECLEAR, NULL);
+
+ dev_dbg(pps->dev, "PPS %s at %lu\n",
+ active ? "assert" : "clear", jiffies);
+}
+
+static int (*alias_n_tty_open)(struct tty_struct *tty);
+
+static int pps_tty_open(struct tty_struct *tty)
+{
+ struct pps_source_info info;
+ struct tty_driver *drv = tty->driver;
+ int index = tty->index + drv->name_base;
+ struct pps_device *pps;
+ int ret;
+
+ info.owner = THIS_MODULE;
+ info.dev = NULL;
+ snprintf(info.name, PPS_MAX_NAME_LEN, "%s%d", drv->driver_name, index);
+ snprintf(info.path, PPS_MAX_NAME_LEN, "/dev/%s%d", drv->name, index);
+ info.mode = PPS_CAPTUREBOTH | \
+ PPS_OFFSETASSERT | PPS_OFFSETCLEAR | \
+ PPS_CANWAIT | PPS_TSFMT_TSPEC;
+
+ pps = pps_register_source(&info, PPS_CAPTUREBOTH | \
+ PPS_OFFSETASSERT | PPS_OFFSETCLEAR);
+ if (IS_ERR(pps)) {
+ pr_err("cannot register PPS source \"%s\"\n", info.path);
+ return PTR_ERR(pps);
+ }
+ pps->lookup_cookie = tty;
+
+ /* Now open the base class N_TTY ldisc */
+ ret = alias_n_tty_open(tty);
+ if (ret < 0) {
+ pr_err("cannot open tty ldisc \"%s\"\n", info.path);
+ goto err_unregister;
+ }
+
+ dev_info(pps->dev, "source \"%s\" added\n", info.path);
+
+ return 0;
+
+err_unregister:
+ pps_unregister_source(pps);
+ return ret;
+}
+
+static void (*alias_n_tty_close)(struct tty_struct *tty);
+
+static void pps_tty_close(struct tty_struct *tty)
+{
+ struct pps_device *pps = pps_lookup_dev(tty);
+
+ alias_n_tty_close(tty);
+
+ if (WARN_ON(!pps))
+ return;
+
+ dev_info(pps->dev, "removed\n");
+ pps_unregister_source(pps);
+}
+
+static struct tty_ldisc_ops pps_ldisc_ops;
+
+/*
+ * Module stuff
+ */
+
+static int __init pps_tty_init(void)
+{
+ int err;
+
+ /* Inherit the N_TTY's ops */
+ n_tty_inherit_ops(&pps_ldisc_ops);
+
+ /* Save N_TTY's open()/close() methods */
+ alias_n_tty_open = pps_ldisc_ops.open;
+ alias_n_tty_close = pps_ldisc_ops.close;
+
+ /* Init PPS_TTY data */
+ pps_ldisc_ops.owner = THIS_MODULE;
+ pps_ldisc_ops.num = N_PPS;
+ pps_ldisc_ops.name = "pps_tty";
+ pps_ldisc_ops.dcd_change = pps_tty_dcd_change;
+ pps_ldisc_ops.open = pps_tty_open;
+ pps_ldisc_ops.close = pps_tty_close;
+
+ err = tty_register_ldisc(&pps_ldisc_ops);
+ if (err)
+ pr_err("can't register PPS line discipline\n");
+ else
+ pr_info("PPS line discipline registered\n");
+
+ return err;
+}
+
+static void __exit pps_tty_cleanup(void)
+{
+ tty_unregister_ldisc(&pps_ldisc_ops);
+}
+
+module_init(pps_tty_init);
+module_exit(pps_tty_cleanup);
+
+MODULE_ALIAS_LDISC(N_PPS);
+MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
+MODULE_DESCRIPTION("PPS TTY device driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/pps/clients/pps_parport.c b/drivers/pps/clients/pps_parport.c
new file mode 100644
index 0000000000..42f93d4c6e
--- /dev/null
+++ b/drivers/pps/clients/pps_parport.c
@@ -0,0 +1,225 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * pps_parport.c -- kernel parallel port PPS client
+ *
+ * Copyright (C) 2009 Alexander Gordeev <lasaine@lvk.cs.msu.su>
+ */
+
+
+/*
+ * TODO:
+ * implement echo over SEL pin
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/irqnr.h>
+#include <linux/time.h>
+#include <linux/slab.h>
+#include <linux/parport.h>
+#include <linux/pps_kernel.h>
+
+/* module parameters */
+
+#define CLEAR_WAIT_MAX 100
+#define CLEAR_WAIT_MAX_ERRORS 5
+
+static unsigned int clear_wait = 100;
+MODULE_PARM_DESC(clear_wait,
+ "Maximum number of port reads when polling for signal clear,"
+ " zero turns clear edge capture off entirely");
+module_param(clear_wait, uint, 0);
+
+static DEFINE_IDA(pps_client_index);
+
+/* internal per port structure */
+struct pps_client_pp {
+ struct pardevice *pardev; /* parport device */
+ struct pps_device *pps; /* PPS device */
+ unsigned int cw; /* port clear timeout */
+ unsigned int cw_err; /* number of timeouts */
+ int index; /* device number */
+};
+
+static inline int signal_is_set(struct parport *port)
+{
+ return (port->ops->read_status(port) & PARPORT_STATUS_ACK) != 0;
+}
+
+/* parport interrupt handler */
+static void parport_irq(void *handle)
+{
+ struct pps_event_time ts_assert, ts_clear;
+ struct pps_client_pp *dev = handle;
+ struct parport *port = dev->pardev->port;
+ unsigned int i;
+ unsigned long flags;
+
+ /* first of all we get the time stamp... */
+ pps_get_ts(&ts_assert);
+
+ if (dev->cw == 0)
+ /* clear edge capture disabled */
+ goto out_assert;
+
+ /* try capture the clear edge */
+
+ /* We have to disable interrupts here. The idea is to prevent
+ * other interrupts on the same processor to introduce random
+ * lags while polling the port. Reading from IO port is known
+ * to take approximately 1us while other interrupt handlers can
+ * take much more potentially.
+ *
+ * Interrupts won't be disabled for a long time because the
+ * number of polls is limited by clear_wait parameter which is
+ * kept rather low. So it should never be an issue.
+ */
+ local_irq_save(flags);
+ /* check the signal (no signal means the pulse is lost this time) */
+ if (!signal_is_set(port)) {
+ local_irq_restore(flags);
+ dev_err(dev->pps->dev, "lost the signal\n");
+ goto out_assert;
+ }
+
+ /* poll the port until the signal is unset */
+ for (i = dev->cw; i; i--)
+ if (!signal_is_set(port)) {
+ pps_get_ts(&ts_clear);
+ local_irq_restore(flags);
+ dev->cw_err = 0;
+ goto out_both;
+ }
+ local_irq_restore(flags);
+
+ /* timeout */
+ dev->cw_err++;
+ if (dev->cw_err >= CLEAR_WAIT_MAX_ERRORS) {
+ dev_err(dev->pps->dev, "disabled clear edge capture after %d"
+ " timeouts\n", dev->cw_err);
+ dev->cw = 0;
+ dev->cw_err = 0;
+ }
+
+out_assert:
+ /* fire assert event */
+ pps_event(dev->pps, &ts_assert,
+ PPS_CAPTUREASSERT, NULL);
+ return;
+
+out_both:
+ /* fire assert event */
+ pps_event(dev->pps, &ts_assert,
+ PPS_CAPTUREASSERT, NULL);
+ /* fire clear event */
+ pps_event(dev->pps, &ts_clear,
+ PPS_CAPTURECLEAR, NULL);
+ return;
+}
+
+static void parport_attach(struct parport *port)
+{
+ struct pardev_cb pps_client_cb;
+ int index;
+ struct pps_client_pp *device;
+ struct pps_source_info info = {
+ .name = KBUILD_MODNAME,
+ .path = "",
+ .mode = PPS_CAPTUREBOTH | \
+ PPS_OFFSETASSERT | PPS_OFFSETCLEAR | \
+ PPS_ECHOASSERT | PPS_ECHOCLEAR | \
+ PPS_CANWAIT | PPS_TSFMT_TSPEC,
+ .owner = THIS_MODULE,
+ .dev = NULL
+ };
+
+ if (clear_wait > CLEAR_WAIT_MAX) {
+ pr_err("clear_wait value should be not greater then %d\n",
+ CLEAR_WAIT_MAX);
+ return;
+ }
+
+ device = kzalloc(sizeof(struct pps_client_pp), GFP_KERNEL);
+ if (!device) {
+ pr_err("memory allocation failed, not attaching\n");
+ return;
+ }
+
+ index = ida_simple_get(&pps_client_index, 0, 0, GFP_KERNEL);
+ memset(&pps_client_cb, 0, sizeof(pps_client_cb));
+ pps_client_cb.private = device;
+ pps_client_cb.irq_func = parport_irq;
+ pps_client_cb.flags = PARPORT_FLAG_EXCL;
+ device->pardev = parport_register_dev_model(port,
+ KBUILD_MODNAME,
+ &pps_client_cb,
+ index);
+ if (!device->pardev) {
+ pr_err("couldn't register with %s\n", port->name);
+ goto err_free;
+ }
+
+ if (parport_claim_or_block(device->pardev) < 0) {
+ pr_err("couldn't claim %s\n", port->name);
+ goto err_unregister_dev;
+ }
+
+ device->pps = pps_register_source(&info,
+ PPS_CAPTUREBOTH | PPS_OFFSETASSERT | PPS_OFFSETCLEAR);
+ if (IS_ERR(device->pps)) {
+ pr_err("couldn't register PPS source\n");
+ goto err_release_dev;
+ }
+
+ device->cw = clear_wait;
+
+ port->ops->enable_irq(port);
+ device->index = index;
+
+ pr_info("attached to %s\n", port->name);
+
+ return;
+
+err_release_dev:
+ parport_release(device->pardev);
+err_unregister_dev:
+ parport_unregister_device(device->pardev);
+err_free:
+ ida_simple_remove(&pps_client_index, index);
+ kfree(device);
+}
+
+static void parport_detach(struct parport *port)
+{
+ struct pardevice *pardev = port->cad;
+ struct pps_client_pp *device;
+
+ /* FIXME: oooh, this is ugly! */
+ if (!pardev || strcmp(pardev->name, KBUILD_MODNAME))
+ /* not our port */
+ return;
+
+ device = pardev->private;
+
+ port->ops->disable_irq(port);
+ pps_unregister_source(device->pps);
+ parport_release(pardev);
+ parport_unregister_device(pardev);
+ ida_simple_remove(&pps_client_index, device->index);
+ kfree(device);
+}
+
+static struct parport_driver pps_parport_driver = {
+ .name = KBUILD_MODNAME,
+ .match_port = parport_attach,
+ .detach = parport_detach,
+ .devmodel = true,
+};
+module_parport_driver(pps_parport_driver);
+
+MODULE_AUTHOR("Alexander Gordeev <lasaine@lvk.cs.msu.su>");
+MODULE_DESCRIPTION("parallel port PPS client");
+MODULE_LICENSE("GPL");
diff --git a/drivers/pps/generators/Kconfig b/drivers/pps/generators/Kconfig
new file mode 100644
index 0000000000..d615e640fc
--- /dev/null
+++ b/drivers/pps/generators/Kconfig
@@ -0,0 +1,14 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# PPS generators configuration
+#
+
+comment "PPS generators support"
+
+config PPS_GENERATOR_PARPORT
+ tristate "Parallel port PPS signal generator"
+ depends on PARPORT && BROKEN
+ help
+ If you say yes here you get support for a PPS signal generator which
+ utilizes STROBE pin of a parallel port to send PPS signals. It uses
+ parport abstraction layer and hrtimers to precisely control the signal.
diff --git a/drivers/pps/generators/Makefile b/drivers/pps/generators/Makefile
new file mode 100644
index 0000000000..2d56dd0495
--- /dev/null
+++ b/drivers/pps/generators/Makefile
@@ -0,0 +1,10 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Makefile for PPS generators.
+#
+
+obj-$(CONFIG_PPS_GENERATOR_PARPORT) += pps_gen_parport.o
+
+ifeq ($(CONFIG_PPS_DEBUG),y)
+EXTRA_CFLAGS += -DDEBUG
+endif
diff --git a/drivers/pps/generators/pps_gen_parport.c b/drivers/pps/generators/pps_gen_parport.c
new file mode 100644
index 0000000000..b3e084b75c
--- /dev/null
+++ b/drivers/pps/generators/pps_gen_parport.c
@@ -0,0 +1,241 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * pps_gen_parport.c -- kernel parallel port PPS signal generator
+ *
+ * Copyright (C) 2009 Alexander Gordeev <lasaine@lvk.cs.msu.su>
+ */
+
+
+/*
+ * TODO:
+ * fix issues when realtime clock is adjusted in a leap
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/time.h>
+#include <linux/hrtimer.h>
+#include <linux/parport.h>
+
+#define SIGNAL 0
+#define NO_SIGNAL PARPORT_CONTROL_STROBE
+
+/* module parameters */
+
+#define SEND_DELAY_MAX 100000
+
+static unsigned int send_delay = 30000;
+MODULE_PARM_DESC(delay,
+ "Delay between setting and dropping the signal (ns)");
+module_param_named(delay, send_delay, uint, 0);
+
+
+#define SAFETY_INTERVAL 3000 /* set the hrtimer earlier for safety (ns) */
+
+/* internal per port structure */
+struct pps_generator_pp {
+ struct pardevice *pardev; /* parport device */
+ struct hrtimer timer;
+ long port_write_time; /* calibrated port write time (ns) */
+};
+
+static struct pps_generator_pp device = {
+ .pardev = NULL,
+};
+
+static int attached;
+
+/* calibrated time between a hrtimer event and the reaction */
+static long hrtimer_error = SAFETY_INTERVAL;
+
+/* the kernel hrtimer event */
+static enum hrtimer_restart hrtimer_event(struct hrtimer *timer)
+{
+ struct timespec64 expire_time, ts1, ts2, ts3, dts;
+ struct pps_generator_pp *dev;
+ struct parport *port;
+ long lim, delta;
+ unsigned long flags;
+
+ /* We have to disable interrupts here. The idea is to prevent
+ * other interrupts on the same processor to introduce random
+ * lags while polling the clock. ktime_get_real_ts64() takes <1us on
+ * most machines while other interrupt handlers can take much
+ * more potentially.
+ *
+ * NB: approx time with blocked interrupts =
+ * send_delay + 3 * SAFETY_INTERVAL
+ */
+ local_irq_save(flags);
+
+ /* first of all we get the time stamp... */
+ ktime_get_real_ts64(&ts1);
+ expire_time = ktime_to_timespec64(hrtimer_get_softexpires(timer));
+ dev = container_of(timer, struct pps_generator_pp, timer);
+ lim = NSEC_PER_SEC - send_delay - dev->port_write_time;
+
+ /* check if we are late */
+ if (expire_time.tv_sec != ts1.tv_sec || ts1.tv_nsec > lim) {
+ local_irq_restore(flags);
+ pr_err("we are late this time %lld.%09ld\n",
+ (s64)ts1.tv_sec, ts1.tv_nsec);
+ goto done;
+ }
+
+ /* busy loop until the time is right for an assert edge */
+ do {
+ ktime_get_real_ts64(&ts2);
+ } while (expire_time.tv_sec == ts2.tv_sec && ts2.tv_nsec < lim);
+
+ /* set the signal */
+ port = dev->pardev->port;
+ port->ops->write_control(port, SIGNAL);
+
+ /* busy loop until the time is right for a clear edge */
+ lim = NSEC_PER_SEC - dev->port_write_time;
+ do {
+ ktime_get_real_ts64(&ts2);
+ } while (expire_time.tv_sec == ts2.tv_sec && ts2.tv_nsec < lim);
+
+ /* unset the signal */
+ port->ops->write_control(port, NO_SIGNAL);
+
+ ktime_get_real_ts64(&ts3);
+
+ local_irq_restore(flags);
+
+ /* update calibrated port write time */
+ dts = timespec64_sub(ts3, ts2);
+ dev->port_write_time =
+ (dev->port_write_time + timespec64_to_ns(&dts)) >> 1;
+
+done:
+ /* update calibrated hrtimer error */
+ dts = timespec64_sub(ts1, expire_time);
+ delta = timespec64_to_ns(&dts);
+ /* If the new error value is bigger then the old, use the new
+ * value, if not then slowly move towards the new value. This
+ * way it should be safe in bad conditions and efficient in
+ * good conditions.
+ */
+ if (delta >= hrtimer_error)
+ hrtimer_error = delta;
+ else
+ hrtimer_error = (3 * hrtimer_error + delta) >> 2;
+
+ /* update the hrtimer expire time */
+ hrtimer_set_expires(timer,
+ ktime_set(expire_time.tv_sec + 1,
+ NSEC_PER_SEC - (send_delay +
+ dev->port_write_time + SAFETY_INTERVAL +
+ 2 * hrtimer_error)));
+
+ return HRTIMER_RESTART;
+}
+
+/* calibrate port write time */
+#define PORT_NTESTS_SHIFT 5
+static void calibrate_port(struct pps_generator_pp *dev)
+{
+ struct parport *port = dev->pardev->port;
+ int i;
+ long acc = 0;
+
+ for (i = 0; i < (1 << PORT_NTESTS_SHIFT); i++) {
+ struct timespec64 a, b;
+ unsigned long irq_flags;
+
+ local_irq_save(irq_flags);
+ ktime_get_real_ts64(&a);
+ port->ops->write_control(port, NO_SIGNAL);
+ ktime_get_real_ts64(&b);
+ local_irq_restore(irq_flags);
+
+ b = timespec64_sub(b, a);
+ acc += timespec64_to_ns(&b);
+ }
+
+ dev->port_write_time = acc >> PORT_NTESTS_SHIFT;
+ pr_info("port write takes %ldns\n", dev->port_write_time);
+}
+
+static inline ktime_t next_intr_time(struct pps_generator_pp *dev)
+{
+ struct timespec64 ts;
+
+ ktime_get_real_ts64(&ts);
+
+ return ktime_set(ts.tv_sec +
+ ((ts.tv_nsec > 990 * NSEC_PER_MSEC) ? 1 : 0),
+ NSEC_PER_SEC - (send_delay +
+ dev->port_write_time + 3 * SAFETY_INTERVAL));
+}
+
+static void parport_attach(struct parport *port)
+{
+ struct pardev_cb pps_cb;
+
+ if (send_delay > SEND_DELAY_MAX) {
+ pr_err("delay value should be not greater then %d\n", SEND_DELAY_MAX);
+ return;
+ }
+
+ if (attached) {
+ /* we already have a port */
+ return;
+ }
+
+ memset(&pps_cb, 0, sizeof(pps_cb));
+ pps_cb.private = &device;
+ pps_cb.flags = PARPORT_FLAG_EXCL;
+ device.pardev = parport_register_dev_model(port, KBUILD_MODNAME,
+ &pps_cb, 0);
+ if (!device.pardev) {
+ pr_err("couldn't register with %s\n", port->name);
+ return;
+ }
+
+ if (parport_claim_or_block(device.pardev) < 0) {
+ pr_err("couldn't claim %s\n", port->name);
+ goto err_unregister_dev;
+ }
+
+ pr_info("attached to %s\n", port->name);
+ attached = 1;
+
+ calibrate_port(&device);
+
+ hrtimer_init(&device.timer, CLOCK_REALTIME, HRTIMER_MODE_ABS);
+ device.timer.function = hrtimer_event;
+ hrtimer_start(&device.timer, next_intr_time(&device), HRTIMER_MODE_ABS);
+
+ return;
+
+err_unregister_dev:
+ parport_unregister_device(device.pardev);
+}
+
+static void parport_detach(struct parport *port)
+{
+ if (port->cad != device.pardev)
+ return; /* not our port */
+
+ hrtimer_cancel(&device.timer);
+ parport_release(device.pardev);
+ parport_unregister_device(device.pardev);
+}
+
+static struct parport_driver pps_gen_parport_driver = {
+ .name = KBUILD_MODNAME,
+ .match_port = parport_attach,
+ .detach = parport_detach,
+ .devmodel = true,
+};
+module_parport_driver(pps_gen_parport_driver);
+
+MODULE_AUTHOR("Alexander Gordeev <lasaine@lvk.cs.msu.su>");
+MODULE_DESCRIPTION("parallel port PPS signal generator");
+MODULE_LICENSE("GPL");
diff --git a/drivers/pps/kapi.c b/drivers/pps/kapi.c
new file mode 100644
index 0000000000..d9d566f70e
--- /dev/null
+++ b/drivers/pps/kapi.c
@@ -0,0 +1,223 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * kernel API
+ *
+ * Copyright (C) 2005-2009 Rodolfo Giometti <giometti@linux.it>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/time.h>
+#include <linux/timex.h>
+#include <linux/spinlock.h>
+#include <linux/fs.h>
+#include <linux/pps_kernel.h>
+#include <linux/slab.h>
+
+#include "kc.h"
+
+/*
+ * Local functions
+ */
+
+static void pps_add_offset(struct pps_ktime *ts, struct pps_ktime *offset)
+{
+ ts->nsec += offset->nsec;
+ while (ts->nsec >= NSEC_PER_SEC) {
+ ts->nsec -= NSEC_PER_SEC;
+ ts->sec++;
+ }
+ while (ts->nsec < 0) {
+ ts->nsec += NSEC_PER_SEC;
+ ts->sec--;
+ }
+ ts->sec += offset->sec;
+}
+
+static void pps_echo_client_default(struct pps_device *pps, int event,
+ void *data)
+{
+ dev_info(pps->dev, "echo %s %s\n",
+ event & PPS_CAPTUREASSERT ? "assert" : "",
+ event & PPS_CAPTURECLEAR ? "clear" : "");
+}
+
+/*
+ * Exported functions
+ */
+
+/* pps_register_source - add a PPS source in the system
+ * @info: the PPS info struct
+ * @default_params: the default PPS parameters of the new source
+ *
+ * This function is used to add a new PPS source in the system. The new
+ * source is described by info's fields and it will have, as default PPS
+ * parameters, the ones specified into default_params.
+ *
+ * The function returns, in case of success, the PPS device. Otherwise
+ * ERR_PTR(errno).
+ */
+
+struct pps_device *pps_register_source(struct pps_source_info *info,
+ int default_params)
+{
+ struct pps_device *pps;
+ int err;
+
+ /* Sanity checks */
+ if ((info->mode & default_params) != default_params) {
+ pr_err("%s: unsupported default parameters\n",
+ info->name);
+ err = -EINVAL;
+ goto pps_register_source_exit;
+ }
+ if ((info->mode & (PPS_TSFMT_TSPEC | PPS_TSFMT_NTPFP)) == 0) {
+ pr_err("%s: unspecified time format\n",
+ info->name);
+ err = -EINVAL;
+ goto pps_register_source_exit;
+ }
+
+ /* Allocate memory for the new PPS source struct */
+ pps = kzalloc(sizeof(struct pps_device), GFP_KERNEL);
+ if (pps == NULL) {
+ err = -ENOMEM;
+ goto pps_register_source_exit;
+ }
+
+ /* These initializations must be done before calling idr_alloc()
+ * in order to avoid reces into pps_event().
+ */
+ pps->params.api_version = PPS_API_VERS;
+ pps->params.mode = default_params;
+ pps->info = *info;
+
+ /* check for default echo function */
+ if ((pps->info.mode & (PPS_ECHOASSERT | PPS_ECHOCLEAR)) &&
+ pps->info.echo == NULL)
+ pps->info.echo = pps_echo_client_default;
+
+ init_waitqueue_head(&pps->queue);
+ spin_lock_init(&pps->lock);
+
+ /* Create the char device */
+ err = pps_register_cdev(pps);
+ if (err < 0) {
+ pr_err("%s: unable to create char device\n",
+ info->name);
+ goto kfree_pps;
+ }
+
+ dev_info(pps->dev, "new PPS source %s\n", info->name);
+
+ return pps;
+
+kfree_pps:
+ kfree(pps);
+
+pps_register_source_exit:
+ pr_err("%s: unable to register source\n", info->name);
+
+ return ERR_PTR(err);
+}
+EXPORT_SYMBOL(pps_register_source);
+
+/* pps_unregister_source - remove a PPS source from the system
+ * @pps: the PPS source
+ *
+ * This function is used to remove a previously registered PPS source from
+ * the system.
+ */
+
+void pps_unregister_source(struct pps_device *pps)
+{
+ pps_kc_remove(pps);
+ pps_unregister_cdev(pps);
+
+ /* don't have to kfree(pps) here because it will be done on
+ * device destruction */
+}
+EXPORT_SYMBOL(pps_unregister_source);
+
+/* pps_event - register a PPS event into the system
+ * @pps: the PPS device
+ * @ts: the event timestamp
+ * @event: the event type
+ * @data: userdef pointer
+ *
+ * This function is used by each PPS client in order to register a new
+ * PPS event into the system (it's usually called inside an IRQ handler).
+ *
+ * If an echo function is associated with the PPS device it will be called
+ * as:
+ * pps->info.echo(pps, event, data);
+ */
+void pps_event(struct pps_device *pps, struct pps_event_time *ts, int event,
+ void *data)
+{
+ unsigned long flags;
+ int captured = 0;
+ struct pps_ktime ts_real = { .sec = 0, .nsec = 0, .flags = 0 };
+
+ /* check event type */
+ BUG_ON((event & (PPS_CAPTUREASSERT | PPS_CAPTURECLEAR)) == 0);
+
+ dev_dbg(pps->dev, "PPS event at %lld.%09ld\n",
+ (s64)ts->ts_real.tv_sec, ts->ts_real.tv_nsec);
+
+ timespec_to_pps_ktime(&ts_real, ts->ts_real);
+
+ spin_lock_irqsave(&pps->lock, flags);
+
+ /* Must call the echo function? */
+ if ((pps->params.mode & (PPS_ECHOASSERT | PPS_ECHOCLEAR)))
+ pps->info.echo(pps, event, data);
+
+ /* Check the event */
+ pps->current_mode = pps->params.mode;
+ if (event & pps->params.mode & PPS_CAPTUREASSERT) {
+ /* We have to add an offset? */
+ if (pps->params.mode & PPS_OFFSETASSERT)
+ pps_add_offset(&ts_real,
+ &pps->params.assert_off_tu);
+
+ /* Save the time stamp */
+ pps->assert_tu = ts_real;
+ pps->assert_sequence++;
+ dev_dbg(pps->dev, "capture assert seq #%u\n",
+ pps->assert_sequence);
+
+ captured = ~0;
+ }
+ if (event & pps->params.mode & PPS_CAPTURECLEAR) {
+ /* We have to add an offset? */
+ if (pps->params.mode & PPS_OFFSETCLEAR)
+ pps_add_offset(&ts_real,
+ &pps->params.clear_off_tu);
+
+ /* Save the time stamp */
+ pps->clear_tu = ts_real;
+ pps->clear_sequence++;
+ dev_dbg(pps->dev, "capture clear seq #%u\n",
+ pps->clear_sequence);
+
+ captured = ~0;
+ }
+
+ pps_kc_event(pps, ts, event);
+
+ /* Wake up if captured something */
+ if (captured) {
+ pps->last_ev++;
+ wake_up_interruptible_all(&pps->queue);
+
+ kill_fasync(&pps->async_queue, SIGIO, POLL_IN);
+ }
+
+ spin_unlock_irqrestore(&pps->lock, flags);
+}
+EXPORT_SYMBOL(pps_event);
diff --git a/drivers/pps/kc.c b/drivers/pps/kc.c
new file mode 100644
index 0000000000..50dc59af45
--- /dev/null
+++ b/drivers/pps/kc.c
@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * PPS kernel consumer API
+ *
+ * Copyright (C) 2009-2010 Alexander Gordeev <lasaine@lvk.cs.msu.su>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/pps_kernel.h>
+
+#include "kc.h"
+
+/*
+ * Global variables
+ */
+
+/* state variables to bind kernel consumer */
+static DEFINE_SPINLOCK(pps_kc_hardpps_lock);
+/* PPS API (RFC 2783): current source and mode for kernel consumer */
+static struct pps_device *pps_kc_hardpps_dev; /* unique pointer to device */
+static int pps_kc_hardpps_mode; /* mode bits for kernel consumer */
+
+/* pps_kc_bind - control PPS kernel consumer binding
+ * @pps: the PPS source
+ * @bind_args: kernel consumer bind parameters
+ *
+ * This function is used to bind or unbind PPS kernel consumer according to
+ * supplied parameters. Should not be called in interrupt context.
+ */
+int pps_kc_bind(struct pps_device *pps, struct pps_bind_args *bind_args)
+{
+ /* Check if another consumer is already bound */
+ spin_lock_irq(&pps_kc_hardpps_lock);
+
+ if (bind_args->edge == 0)
+ if (pps_kc_hardpps_dev == pps) {
+ pps_kc_hardpps_mode = 0;
+ pps_kc_hardpps_dev = NULL;
+ spin_unlock_irq(&pps_kc_hardpps_lock);
+ dev_info(pps->dev, "unbound kernel"
+ " consumer\n");
+ } else {
+ spin_unlock_irq(&pps_kc_hardpps_lock);
+ dev_err(pps->dev, "selected kernel consumer"
+ " is not bound\n");
+ return -EINVAL;
+ }
+ else
+ if (pps_kc_hardpps_dev == NULL ||
+ pps_kc_hardpps_dev == pps) {
+ pps_kc_hardpps_mode = bind_args->edge;
+ pps_kc_hardpps_dev = pps;
+ spin_unlock_irq(&pps_kc_hardpps_lock);
+ dev_info(pps->dev, "bound kernel consumer: "
+ "edge=0x%x\n", bind_args->edge);
+ } else {
+ spin_unlock_irq(&pps_kc_hardpps_lock);
+ dev_err(pps->dev, "another kernel consumer"
+ " is already bound\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/* pps_kc_remove - unbind kernel consumer on PPS source removal
+ * @pps: the PPS source
+ *
+ * This function is used to disable kernel consumer on PPS source removal
+ * if this source was bound to PPS kernel consumer. Can be called on any
+ * source safely. Should not be called in interrupt context.
+ */
+void pps_kc_remove(struct pps_device *pps)
+{
+ spin_lock_irq(&pps_kc_hardpps_lock);
+ if (pps == pps_kc_hardpps_dev) {
+ pps_kc_hardpps_mode = 0;
+ pps_kc_hardpps_dev = NULL;
+ spin_unlock_irq(&pps_kc_hardpps_lock);
+ dev_info(pps->dev, "unbound kernel consumer"
+ " on device removal\n");
+ } else
+ spin_unlock_irq(&pps_kc_hardpps_lock);
+}
+
+/* pps_kc_event - call hardpps() on PPS event
+ * @pps: the PPS source
+ * @ts: PPS event timestamp
+ * @event: PPS event edge
+ *
+ * This function calls hardpps() when an event from bound PPS source occurs.
+ */
+void pps_kc_event(struct pps_device *pps, struct pps_event_time *ts,
+ int event)
+{
+ unsigned long flags;
+
+ /* Pass some events to kernel consumer if activated */
+ spin_lock_irqsave(&pps_kc_hardpps_lock, flags);
+ if (pps == pps_kc_hardpps_dev && event & pps_kc_hardpps_mode)
+ hardpps(&ts->ts_real, &ts->ts_raw);
+ spin_unlock_irqrestore(&pps_kc_hardpps_lock, flags);
+}
diff --git a/drivers/pps/kc.h b/drivers/pps/kc.h
new file mode 100644
index 0000000000..2473055944
--- /dev/null
+++ b/drivers/pps/kc.h
@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * PPS kernel consumer API header
+ *
+ * Copyright (C) 2009-2010 Alexander Gordeev <lasaine@lvk.cs.msu.su>
+ */
+
+#ifndef LINUX_PPS_KC_H
+#define LINUX_PPS_KC_H
+
+#include <linux/errno.h>
+#include <linux/pps_kernel.h>
+
+#ifdef CONFIG_NTP_PPS
+
+extern int pps_kc_bind(struct pps_device *pps,
+ struct pps_bind_args *bind_args);
+extern void pps_kc_remove(struct pps_device *pps);
+extern void pps_kc_event(struct pps_device *pps,
+ struct pps_event_time *ts, int event);
+
+
+#else /* CONFIG_NTP_PPS */
+
+static inline int pps_kc_bind(struct pps_device *pps,
+ struct pps_bind_args *bind_args) { return -EOPNOTSUPP; }
+static inline void pps_kc_remove(struct pps_device *pps) {}
+static inline void pps_kc_event(struct pps_device *pps,
+ struct pps_event_time *ts, int event) {}
+
+#endif /* CONFIG_NTP_PPS */
+
+#endif /* LINUX_PPS_KC_H */
diff --git a/drivers/pps/pps.c b/drivers/pps/pps.c
new file mode 100644
index 0000000000..5d19baae6a
--- /dev/null
+++ b/drivers/pps/pps.c
@@ -0,0 +1,489 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * PPS core file
+ *
+ * Copyright (C) 2005-2009 Rodolfo Giometti <giometti@linux.it>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/uaccess.h>
+#include <linux/idr.h>
+#include <linux/mutex.h>
+#include <linux/cdev.h>
+#include <linux/poll.h>
+#include <linux/pps_kernel.h>
+#include <linux/slab.h>
+
+#include "kc.h"
+
+/*
+ * Local variables
+ */
+
+static dev_t pps_devt;
+static struct class *pps_class;
+
+static DEFINE_MUTEX(pps_idr_lock);
+static DEFINE_IDR(pps_idr);
+
+/*
+ * Char device methods
+ */
+
+static __poll_t pps_cdev_poll(struct file *file, poll_table *wait)
+{
+ struct pps_device *pps = file->private_data;
+
+ poll_wait(file, &pps->queue, wait);
+
+ return EPOLLIN | EPOLLRDNORM;
+}
+
+static int pps_cdev_fasync(int fd, struct file *file, int on)
+{
+ struct pps_device *pps = file->private_data;
+ return fasync_helper(fd, file, on, &pps->async_queue);
+}
+
+static int pps_cdev_pps_fetch(struct pps_device *pps, struct pps_fdata *fdata)
+{
+ unsigned int ev = pps->last_ev;
+ int err = 0;
+
+ /* Manage the timeout */
+ if (fdata->timeout.flags & PPS_TIME_INVALID)
+ err = wait_event_interruptible(pps->queue,
+ ev != pps->last_ev);
+ else {
+ unsigned long ticks;
+
+ dev_dbg(pps->dev, "timeout %lld.%09d\n",
+ (long long) fdata->timeout.sec,
+ fdata->timeout.nsec);
+ ticks = fdata->timeout.sec * HZ;
+ ticks += fdata->timeout.nsec / (NSEC_PER_SEC / HZ);
+
+ if (ticks != 0) {
+ err = wait_event_interruptible_timeout(
+ pps->queue,
+ ev != pps->last_ev,
+ ticks);
+ if (err == 0)
+ return -ETIMEDOUT;
+ }
+ }
+
+ /* Check for pending signals */
+ if (err == -ERESTARTSYS) {
+ dev_dbg(pps->dev, "pending signal caught\n");
+ return -EINTR;
+ }
+
+ return 0;
+}
+
+static long pps_cdev_ioctl(struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ struct pps_device *pps = file->private_data;
+ struct pps_kparams params;
+ void __user *uarg = (void __user *) arg;
+ int __user *iuarg = (int __user *) arg;
+ int err;
+
+ switch (cmd) {
+ case PPS_GETPARAMS:
+ dev_dbg(pps->dev, "PPS_GETPARAMS\n");
+
+ spin_lock_irq(&pps->lock);
+
+ /* Get the current parameters */
+ params = pps->params;
+
+ spin_unlock_irq(&pps->lock);
+
+ err = copy_to_user(uarg, &params, sizeof(struct pps_kparams));
+ if (err)
+ return -EFAULT;
+
+ break;
+
+ case PPS_SETPARAMS:
+ dev_dbg(pps->dev, "PPS_SETPARAMS\n");
+
+ /* Check the capabilities */
+ if (!capable(CAP_SYS_TIME))
+ return -EPERM;
+
+ err = copy_from_user(&params, uarg, sizeof(struct pps_kparams));
+ if (err)
+ return -EFAULT;
+ if (!(params.mode & (PPS_CAPTUREASSERT | PPS_CAPTURECLEAR))) {
+ dev_dbg(pps->dev, "capture mode unspecified (%x)\n",
+ params.mode);
+ return -EINVAL;
+ }
+
+ /* Check for supported capabilities */
+ if ((params.mode & ~pps->info.mode) != 0) {
+ dev_dbg(pps->dev, "unsupported capabilities (%x)\n",
+ params.mode);
+ return -EINVAL;
+ }
+
+ spin_lock_irq(&pps->lock);
+
+ /* Save the new parameters */
+ pps->params = params;
+
+ /* Restore the read only parameters */
+ if ((params.mode & (PPS_TSFMT_TSPEC | PPS_TSFMT_NTPFP)) == 0) {
+ /* section 3.3 of RFC 2783 interpreted */
+ dev_dbg(pps->dev, "time format unspecified (%x)\n",
+ params.mode);
+ pps->params.mode |= PPS_TSFMT_TSPEC;
+ }
+ if (pps->info.mode & PPS_CANWAIT)
+ pps->params.mode |= PPS_CANWAIT;
+ pps->params.api_version = PPS_API_VERS;
+
+ /*
+ * Clear unused fields of pps_kparams to avoid leaking
+ * uninitialized data of the PPS_SETPARAMS caller via
+ * PPS_GETPARAMS
+ */
+ pps->params.assert_off_tu.flags = 0;
+ pps->params.clear_off_tu.flags = 0;
+
+ spin_unlock_irq(&pps->lock);
+
+ break;
+
+ case PPS_GETCAP:
+ dev_dbg(pps->dev, "PPS_GETCAP\n");
+
+ err = put_user(pps->info.mode, iuarg);
+ if (err)
+ return -EFAULT;
+
+ break;
+
+ case PPS_FETCH: {
+ struct pps_fdata fdata;
+
+ dev_dbg(pps->dev, "PPS_FETCH\n");
+
+ err = copy_from_user(&fdata, uarg, sizeof(struct pps_fdata));
+ if (err)
+ return -EFAULT;
+
+ err = pps_cdev_pps_fetch(pps, &fdata);
+ if (err)
+ return err;
+
+ /* Return the fetched timestamp */
+ spin_lock_irq(&pps->lock);
+
+ fdata.info.assert_sequence = pps->assert_sequence;
+ fdata.info.clear_sequence = pps->clear_sequence;
+ fdata.info.assert_tu = pps->assert_tu;
+ fdata.info.clear_tu = pps->clear_tu;
+ fdata.info.current_mode = pps->current_mode;
+
+ spin_unlock_irq(&pps->lock);
+
+ err = copy_to_user(uarg, &fdata, sizeof(struct pps_fdata));
+ if (err)
+ return -EFAULT;
+
+ break;
+ }
+ case PPS_KC_BIND: {
+ struct pps_bind_args bind_args;
+
+ dev_dbg(pps->dev, "PPS_KC_BIND\n");
+
+ /* Check the capabilities */
+ if (!capable(CAP_SYS_TIME))
+ return -EPERM;
+
+ if (copy_from_user(&bind_args, uarg,
+ sizeof(struct pps_bind_args)))
+ return -EFAULT;
+
+ /* Check for supported capabilities */
+ if ((bind_args.edge & ~pps->info.mode) != 0) {
+ dev_err(pps->dev, "unsupported capabilities (%x)\n",
+ bind_args.edge);
+ return -EINVAL;
+ }
+
+ /* Validate parameters roughly */
+ if (bind_args.tsformat != PPS_TSFMT_TSPEC ||
+ (bind_args.edge & ~PPS_CAPTUREBOTH) != 0 ||
+ bind_args.consumer != PPS_KC_HARDPPS) {
+ dev_err(pps->dev, "invalid kernel consumer bind"
+ " parameters (%x)\n", bind_args.edge);
+ return -EINVAL;
+ }
+
+ err = pps_kc_bind(pps, &bind_args);
+ if (err < 0)
+ return err;
+
+ break;
+ }
+ default:
+ return -ENOTTY;
+ }
+
+ return 0;
+}
+
+#ifdef CONFIG_COMPAT
+static long pps_cdev_compat_ioctl(struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ struct pps_device *pps = file->private_data;
+ void __user *uarg = (void __user *) arg;
+
+ cmd = _IOC(_IOC_DIR(cmd), _IOC_TYPE(cmd), _IOC_NR(cmd), sizeof(void *));
+
+ if (cmd == PPS_FETCH) {
+ struct pps_fdata_compat compat;
+ struct pps_fdata fdata;
+ int err;
+
+ dev_dbg(pps->dev, "PPS_FETCH\n");
+
+ err = copy_from_user(&compat, uarg, sizeof(struct pps_fdata_compat));
+ if (err)
+ return -EFAULT;
+
+ memcpy(&fdata.timeout, &compat.timeout,
+ sizeof(struct pps_ktime_compat));
+
+ err = pps_cdev_pps_fetch(pps, &fdata);
+ if (err)
+ return err;
+
+ /* Return the fetched timestamp */
+ spin_lock_irq(&pps->lock);
+
+ compat.info.assert_sequence = pps->assert_sequence;
+ compat.info.clear_sequence = pps->clear_sequence;
+ compat.info.current_mode = pps->current_mode;
+
+ memcpy(&compat.info.assert_tu, &pps->assert_tu,
+ sizeof(struct pps_ktime_compat));
+ memcpy(&compat.info.clear_tu, &pps->clear_tu,
+ sizeof(struct pps_ktime_compat));
+
+ spin_unlock_irq(&pps->lock);
+
+ return copy_to_user(uarg, &compat,
+ sizeof(struct pps_fdata_compat)) ? -EFAULT : 0;
+ }
+
+ return pps_cdev_ioctl(file, cmd, arg);
+}
+#else
+#define pps_cdev_compat_ioctl NULL
+#endif
+
+static int pps_cdev_open(struct inode *inode, struct file *file)
+{
+ struct pps_device *pps = container_of(inode->i_cdev,
+ struct pps_device, cdev);
+ file->private_data = pps;
+ kobject_get(&pps->dev->kobj);
+ return 0;
+}
+
+static int pps_cdev_release(struct inode *inode, struct file *file)
+{
+ struct pps_device *pps = container_of(inode->i_cdev,
+ struct pps_device, cdev);
+ kobject_put(&pps->dev->kobj);
+ return 0;
+}
+
+/*
+ * Char device stuff
+ */
+
+static const struct file_operations pps_cdev_fops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .poll = pps_cdev_poll,
+ .fasync = pps_cdev_fasync,
+ .compat_ioctl = pps_cdev_compat_ioctl,
+ .unlocked_ioctl = pps_cdev_ioctl,
+ .open = pps_cdev_open,
+ .release = pps_cdev_release,
+};
+
+static void pps_device_destruct(struct device *dev)
+{
+ struct pps_device *pps = dev_get_drvdata(dev);
+
+ cdev_del(&pps->cdev);
+
+ /* Now we can release the ID for re-use */
+ pr_debug("deallocating pps%d\n", pps->id);
+ mutex_lock(&pps_idr_lock);
+ idr_remove(&pps_idr, pps->id);
+ mutex_unlock(&pps_idr_lock);
+
+ kfree(dev);
+ kfree(pps);
+}
+
+int pps_register_cdev(struct pps_device *pps)
+{
+ int err;
+ dev_t devt;
+
+ mutex_lock(&pps_idr_lock);
+ /*
+ * Get new ID for the new PPS source. After idr_alloc() calling
+ * the new source will be freely available into the kernel.
+ */
+ err = idr_alloc(&pps_idr, pps, 0, PPS_MAX_SOURCES, GFP_KERNEL);
+ if (err < 0) {
+ if (err == -ENOSPC) {
+ pr_err("%s: too many PPS sources in the system\n",
+ pps->info.name);
+ err = -EBUSY;
+ }
+ goto out_unlock;
+ }
+ pps->id = err;
+ mutex_unlock(&pps_idr_lock);
+
+ devt = MKDEV(MAJOR(pps_devt), pps->id);
+
+ cdev_init(&pps->cdev, &pps_cdev_fops);
+ pps->cdev.owner = pps->info.owner;
+
+ err = cdev_add(&pps->cdev, devt, 1);
+ if (err) {
+ pr_err("%s: failed to add char device %d:%d\n",
+ pps->info.name, MAJOR(pps_devt), pps->id);
+ goto free_idr;
+ }
+ pps->dev = device_create(pps_class, pps->info.dev, devt, pps,
+ "pps%d", pps->id);
+ if (IS_ERR(pps->dev)) {
+ err = PTR_ERR(pps->dev);
+ goto del_cdev;
+ }
+
+ /* Override the release function with our own */
+ pps->dev->release = pps_device_destruct;
+
+ pr_debug("source %s got cdev (%d:%d)\n", pps->info.name,
+ MAJOR(pps_devt), pps->id);
+
+ return 0;
+
+del_cdev:
+ cdev_del(&pps->cdev);
+
+free_idr:
+ mutex_lock(&pps_idr_lock);
+ idr_remove(&pps_idr, pps->id);
+out_unlock:
+ mutex_unlock(&pps_idr_lock);
+ return err;
+}
+
+void pps_unregister_cdev(struct pps_device *pps)
+{
+ pr_debug("unregistering pps%d\n", pps->id);
+ pps->lookup_cookie = NULL;
+ device_destroy(pps_class, pps->dev->devt);
+}
+
+/*
+ * Look up a pps device by magic cookie.
+ * The cookie is usually a pointer to some enclosing device, but this
+ * code doesn't care; you should never be dereferencing it.
+ *
+ * This is a bit of a kludge that is currently used only by the PPS
+ * serial line discipline. It may need to be tweaked when a second user
+ * is found.
+ *
+ * There is no function interface for setting the lookup_cookie field.
+ * It's initialized to NULL when the pps device is created, and if a
+ * client wants to use it, just fill it in afterward.
+ *
+ * The cookie is automatically set to NULL in pps_unregister_source()
+ * so that it will not be used again, even if the pps device cannot
+ * be removed from the idr due to pending references holding the minor
+ * number in use.
+ */
+struct pps_device *pps_lookup_dev(void const *cookie)
+{
+ struct pps_device *pps;
+ unsigned id;
+
+ rcu_read_lock();
+ idr_for_each_entry(&pps_idr, pps, id)
+ if (cookie == pps->lookup_cookie)
+ break;
+ rcu_read_unlock();
+ return pps;
+}
+EXPORT_SYMBOL(pps_lookup_dev);
+
+/*
+ * Module stuff
+ */
+
+static void __exit pps_exit(void)
+{
+ class_destroy(pps_class);
+ unregister_chrdev_region(pps_devt, PPS_MAX_SOURCES);
+}
+
+static int __init pps_init(void)
+{
+ int err;
+
+ pps_class = class_create("pps");
+ if (IS_ERR(pps_class)) {
+ pr_err("failed to allocate class\n");
+ return PTR_ERR(pps_class);
+ }
+ pps_class->dev_groups = pps_groups;
+
+ err = alloc_chrdev_region(&pps_devt, 0, PPS_MAX_SOURCES, "pps");
+ if (err < 0) {
+ pr_err("failed to allocate char device region\n");
+ goto remove_class;
+ }
+
+ pr_info("LinuxPPS API ver. %d registered\n", PPS_API_VERS);
+ pr_info("Software ver. %s - Copyright 2005-2007 Rodolfo Giometti "
+ "<giometti@linux.it>\n", PPS_VERSION);
+
+ return 0;
+
+remove_class:
+ class_destroy(pps_class);
+
+ return err;
+}
+
+subsys_initcall(pps_init);
+module_exit(pps_exit);
+
+MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
+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 0000000000..134bc33f6a
--- /dev/null
+++ b/drivers/pps/sysfs.c
@@ -0,0 +1,99 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * PPS sysfs support
+ *
+ * Copyright (C) 2007-2009 Rodolfo Giometti <giometti@linux.it>
+ */
+
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/pps_kernel.h>
+
+/*
+ * Attribute functions
+ */
+
+static ssize_t assert_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct pps_device *pps = dev_get_drvdata(dev);
+
+ if (!(pps->info.mode & PPS_CAPTUREASSERT))
+ return 0;
+
+ return sprintf(buf, "%lld.%09d#%d\n",
+ (long long) pps->assert_tu.sec, pps->assert_tu.nsec,
+ pps->assert_sequence);
+}
+static DEVICE_ATTR_RO(assert);
+
+static ssize_t clear_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct pps_device *pps = dev_get_drvdata(dev);
+
+ if (!(pps->info.mode & PPS_CAPTURECLEAR))
+ return 0;
+
+ return sprintf(buf, "%lld.%09d#%d\n",
+ (long long) pps->clear_tu.sec, pps->clear_tu.nsec,
+ pps->clear_sequence);
+}
+static DEVICE_ATTR_RO(clear);
+
+static ssize_t mode_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct pps_device *pps = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%4x\n", pps->info.mode);
+}
+static DEVICE_ATTR_RO(mode);
+
+static ssize_t echo_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct pps_device *pps = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%d\n", !!pps->info.echo);
+}
+static DEVICE_ATTR_RO(echo);
+
+static ssize_t name_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct pps_device *pps = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%s\n", pps->info.name);
+}
+static DEVICE_ATTR_RO(name);
+
+static ssize_t path_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct pps_device *pps = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%s\n", pps->info.path);
+}
+static DEVICE_ATTR_RO(path);
+
+static struct attribute *pps_attrs[] = {
+ &dev_attr_assert.attr,
+ &dev_attr_clear.attr,
+ &dev_attr_mode.attr,
+ &dev_attr_echo.attr,
+ &dev_attr_name.attr,
+ &dev_attr_path.attr,
+ NULL,
+};
+
+static const struct attribute_group pps_group = {
+ .attrs = pps_attrs,
+};
+
+const struct attribute_group *pps_groups[] = {
+ &pps_group,
+ NULL,
+};
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-11 08:27:04 +0000