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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /drivers/ptp/ptp_clock.c
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/ptp/ptp_clock.c')
-rw-r--r--drivers/ptp/ptp_clock.c439
1 files changed, 439 insertions, 0 deletions
diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c
new file mode 100644
index 000000000..ed766943a
--- /dev/null
+++ b/drivers/ptp/ptp_clock.c
@@ -0,0 +1,439 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * PTP 1588 clock support
+ *
+ * Copyright (C) 2010 OMICRON electronics GmbH
+ */
+#include <linux/idr.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/posix-clock.h>
+#include <linux/pps_kernel.h>
+#include <linux/slab.h>
+#include <linux/syscalls.h>
+#include <linux/uaccess.h>
+#include <uapi/linux/sched/types.h>
+
+#include "ptp_private.h"
+
+#define PTP_MAX_ALARMS 4
+#define PTP_PPS_DEFAULTS (PPS_CAPTUREASSERT | PPS_OFFSETASSERT)
+#define PTP_PPS_EVENT PPS_CAPTUREASSERT
+#define PTP_PPS_MODE (PTP_PPS_DEFAULTS | PPS_CANWAIT | PPS_TSFMT_TSPEC)
+
+/* private globals */
+
+static dev_t ptp_devt;
+static struct class *ptp_class;
+
+static DEFINE_IDA(ptp_clocks_map);
+
+/* time stamp event queue operations */
+
+static inline int queue_free(struct timestamp_event_queue *q)
+{
+ return PTP_MAX_TIMESTAMPS - queue_cnt(q) - 1;
+}
+
+static void enqueue_external_timestamp(struct timestamp_event_queue *queue,
+ struct ptp_clock_event *src)
+{
+ struct ptp_extts_event *dst;
+ unsigned long flags;
+ s64 seconds;
+ u32 remainder;
+
+ seconds = div_u64_rem(src->timestamp, 1000000000, &remainder);
+
+ spin_lock_irqsave(&queue->lock, flags);
+
+ dst = &queue->buf[queue->tail];
+ dst->index = src->index;
+ dst->t.sec = seconds;
+ dst->t.nsec = remainder;
+
+ /* Both WRITE_ONCE() are paired with READ_ONCE() in queue_cnt() */
+ if (!queue_free(queue))
+ WRITE_ONCE(queue->head, (queue->head + 1) % PTP_MAX_TIMESTAMPS);
+
+ WRITE_ONCE(queue->tail, (queue->tail + 1) % PTP_MAX_TIMESTAMPS);
+
+ spin_unlock_irqrestore(&queue->lock, flags);
+}
+
+long scaled_ppm_to_ppb(long ppm)
+{
+ /*
+ * The 'freq' field in the 'struct timex' is in parts per
+ * million, but with a 16 bit binary fractional field.
+ *
+ * We want to calculate
+ *
+ * ppb = scaled_ppm * 1000 / 2^16
+ *
+ * which simplifies to
+ *
+ * ppb = scaled_ppm * 125 / 2^13
+ */
+ s64 ppb = 1 + ppm;
+ ppb *= 125;
+ ppb >>= 13;
+ return (long) ppb;
+}
+EXPORT_SYMBOL(scaled_ppm_to_ppb);
+
+/* posix clock implementation */
+
+static int ptp_clock_getres(struct posix_clock *pc, struct timespec64 *tp)
+{
+ tp->tv_sec = 0;
+ tp->tv_nsec = 1;
+ return 0;
+}
+
+static int ptp_clock_settime(struct posix_clock *pc, const struct timespec64 *tp)
+{
+ struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
+
+ return ptp->info->settime64(ptp->info, tp);
+}
+
+static int ptp_clock_gettime(struct posix_clock *pc, struct timespec64 *tp)
+{
+ struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
+ int err;
+
+ if (ptp->info->gettimex64)
+ err = ptp->info->gettimex64(ptp->info, tp, NULL);
+ else
+ err = ptp->info->gettime64(ptp->info, tp);
+ return err;
+}
+
+static int ptp_clock_adjtime(struct posix_clock *pc, struct __kernel_timex *tx)
+{
+ struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
+ struct ptp_clock_info *ops;
+ int err = -EOPNOTSUPP;
+
+ ops = ptp->info;
+
+ if (tx->modes & ADJ_SETOFFSET) {
+ struct timespec64 ts;
+ ktime_t kt;
+ s64 delta;
+
+ ts.tv_sec = tx->time.tv_sec;
+ ts.tv_nsec = tx->time.tv_usec;
+
+ if (!(tx->modes & ADJ_NANO))
+ ts.tv_nsec *= 1000;
+
+ if ((unsigned long) ts.tv_nsec >= NSEC_PER_SEC)
+ return -EINVAL;
+
+ kt = timespec64_to_ktime(ts);
+ delta = ktime_to_ns(kt);
+ err = ops->adjtime(ops, delta);
+ } else if (tx->modes & ADJ_FREQUENCY) {
+ long ppb = scaled_ppm_to_ppb(tx->freq);
+ if (ppb > ops->max_adj || ppb < -ops->max_adj)
+ return -ERANGE;
+ if (ops->adjfine)
+ err = ops->adjfine(ops, tx->freq);
+ else
+ err = ops->adjfreq(ops, ppb);
+ ptp->dialed_frequency = tx->freq;
+ } else if (tx->modes & ADJ_OFFSET) {
+ if (ops->adjphase) {
+ s32 offset = tx->offset;
+
+ if (!(tx->modes & ADJ_NANO))
+ offset *= NSEC_PER_USEC;
+
+ err = ops->adjphase(ops, offset);
+ }
+ } else if (tx->modes == 0) {
+ tx->freq = ptp->dialed_frequency;
+ err = 0;
+ }
+
+ return err;
+}
+
+static struct posix_clock_operations ptp_clock_ops = {
+ .owner = THIS_MODULE,
+ .clock_adjtime = ptp_clock_adjtime,
+ .clock_gettime = ptp_clock_gettime,
+ .clock_getres = ptp_clock_getres,
+ .clock_settime = ptp_clock_settime,
+ .ioctl = ptp_ioctl,
+ .open = ptp_open,
+ .poll = ptp_poll,
+ .read = ptp_read,
+};
+
+static void ptp_clock_release(struct device *dev)
+{
+ struct ptp_clock *ptp = container_of(dev, struct ptp_clock, dev);
+
+ ptp_cleanup_pin_groups(ptp);
+ mutex_destroy(&ptp->tsevq_mux);
+ mutex_destroy(&ptp->pincfg_mux);
+ ida_simple_remove(&ptp_clocks_map, ptp->index);
+ kfree(ptp);
+}
+
+static void ptp_aux_kworker(struct kthread_work *work)
+{
+ struct ptp_clock *ptp = container_of(work, struct ptp_clock,
+ aux_work.work);
+ struct ptp_clock_info *info = ptp->info;
+ long delay;
+
+ delay = info->do_aux_work(info);
+
+ if (delay >= 0)
+ kthread_queue_delayed_work(ptp->kworker, &ptp->aux_work, delay);
+}
+
+/* public interface */
+
+struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
+ struct device *parent)
+{
+ struct ptp_clock *ptp;
+ int err = 0, index, major = MAJOR(ptp_devt);
+
+ if (info->n_alarm > PTP_MAX_ALARMS)
+ return ERR_PTR(-EINVAL);
+
+ /* Initialize a clock structure. */
+ err = -ENOMEM;
+ ptp = kzalloc(sizeof(struct ptp_clock), GFP_KERNEL);
+ if (ptp == NULL)
+ goto no_memory;
+
+ index = ida_simple_get(&ptp_clocks_map, 0, MINORMASK + 1, GFP_KERNEL);
+ if (index < 0) {
+ err = index;
+ goto no_slot;
+ }
+
+ ptp->clock.ops = ptp_clock_ops;
+ ptp->info = info;
+ ptp->devid = MKDEV(major, index);
+ ptp->index = index;
+ spin_lock_init(&ptp->tsevq.lock);
+ mutex_init(&ptp->tsevq_mux);
+ mutex_init(&ptp->pincfg_mux);
+ init_waitqueue_head(&ptp->tsev_wq);
+
+ if (ptp->info->do_aux_work) {
+ kthread_init_delayed_work(&ptp->aux_work, ptp_aux_kworker);
+ ptp->kworker = kthread_create_worker(0, "ptp%d", ptp->index);
+ if (IS_ERR(ptp->kworker)) {
+ err = PTR_ERR(ptp->kworker);
+ pr_err("failed to create ptp aux_worker %d\n", err);
+ goto kworker_err;
+ }
+ }
+
+ err = ptp_populate_pin_groups(ptp);
+ if (err)
+ goto no_pin_groups;
+
+ /* Register a new PPS source. */
+ if (info->pps) {
+ struct pps_source_info pps;
+ memset(&pps, 0, sizeof(pps));
+ snprintf(pps.name, PPS_MAX_NAME_LEN, "ptp%d", index);
+ pps.mode = PTP_PPS_MODE;
+ pps.owner = info->owner;
+ ptp->pps_source = pps_register_source(&pps, PTP_PPS_DEFAULTS);
+ if (IS_ERR(ptp->pps_source)) {
+ err = PTR_ERR(ptp->pps_source);
+ pr_err("failed to register pps source\n");
+ goto no_pps;
+ }
+ }
+
+ /* Initialize a new device of our class in our clock structure. */
+ device_initialize(&ptp->dev);
+ ptp->dev.devt = ptp->devid;
+ ptp->dev.class = ptp_class;
+ ptp->dev.parent = parent;
+ ptp->dev.groups = ptp->pin_attr_groups;
+ ptp->dev.release = ptp_clock_release;
+ dev_set_drvdata(&ptp->dev, ptp);
+ dev_set_name(&ptp->dev, "ptp%d", ptp->index);
+
+ /* Create a posix clock and link it to the device. */
+ err = posix_clock_register(&ptp->clock, &ptp->dev);
+ if (err) {
+ pr_err("failed to create posix clock\n");
+ goto no_clock;
+ }
+
+ return ptp;
+
+no_clock:
+ if (ptp->pps_source)
+ pps_unregister_source(ptp->pps_source);
+no_pps:
+ ptp_cleanup_pin_groups(ptp);
+no_pin_groups:
+ if (ptp->kworker)
+ kthread_destroy_worker(ptp->kworker);
+kworker_err:
+ mutex_destroy(&ptp->tsevq_mux);
+ mutex_destroy(&ptp->pincfg_mux);
+ ida_simple_remove(&ptp_clocks_map, index);
+no_slot:
+ kfree(ptp);
+no_memory:
+ return ERR_PTR(err);
+}
+EXPORT_SYMBOL(ptp_clock_register);
+
+int ptp_clock_unregister(struct ptp_clock *ptp)
+{
+ ptp->defunct = 1;
+ wake_up_interruptible(&ptp->tsev_wq);
+
+ if (ptp->kworker) {
+ kthread_cancel_delayed_work_sync(&ptp->aux_work);
+ kthread_destroy_worker(ptp->kworker);
+ }
+
+ /* Release the clock's resources. */
+ if (ptp->pps_source)
+ pps_unregister_source(ptp->pps_source);
+
+ posix_clock_unregister(&ptp->clock);
+
+ return 0;
+}
+EXPORT_SYMBOL(ptp_clock_unregister);
+
+void ptp_clock_event(struct ptp_clock *ptp, struct ptp_clock_event *event)
+{
+ struct pps_event_time evt;
+
+ switch (event->type) {
+
+ case PTP_CLOCK_ALARM:
+ break;
+
+ case PTP_CLOCK_EXTTS:
+ enqueue_external_timestamp(&ptp->tsevq, event);
+ wake_up_interruptible(&ptp->tsev_wq);
+ break;
+
+ case PTP_CLOCK_PPS:
+ pps_get_ts(&evt);
+ pps_event(ptp->pps_source, &evt, PTP_PPS_EVENT, NULL);
+ break;
+
+ case PTP_CLOCK_PPSUSR:
+ pps_event(ptp->pps_source, &event->pps_times,
+ PTP_PPS_EVENT, NULL);
+ break;
+ }
+}
+EXPORT_SYMBOL(ptp_clock_event);
+
+int ptp_clock_index(struct ptp_clock *ptp)
+{
+ return ptp->index;
+}
+EXPORT_SYMBOL(ptp_clock_index);
+
+int ptp_find_pin(struct ptp_clock *ptp,
+ enum ptp_pin_function func, unsigned int chan)
+{
+ struct ptp_pin_desc *pin = NULL;
+ int i;
+
+ for (i = 0; i < ptp->info->n_pins; i++) {
+ if (ptp->info->pin_config[i].func == func &&
+ ptp->info->pin_config[i].chan == chan) {
+ pin = &ptp->info->pin_config[i];
+ break;
+ }
+ }
+
+ return pin ? i : -1;
+}
+EXPORT_SYMBOL(ptp_find_pin);
+
+int ptp_find_pin_unlocked(struct ptp_clock *ptp,
+ enum ptp_pin_function func, unsigned int chan)
+{
+ int result;
+
+ mutex_lock(&ptp->pincfg_mux);
+
+ result = ptp_find_pin(ptp, func, chan);
+
+ mutex_unlock(&ptp->pincfg_mux);
+
+ return result;
+}
+EXPORT_SYMBOL(ptp_find_pin_unlocked);
+
+int ptp_schedule_worker(struct ptp_clock *ptp, unsigned long delay)
+{
+ return kthread_mod_delayed_work(ptp->kworker, &ptp->aux_work, delay);
+}
+EXPORT_SYMBOL(ptp_schedule_worker);
+
+void ptp_cancel_worker_sync(struct ptp_clock *ptp)
+{
+ kthread_cancel_delayed_work_sync(&ptp->aux_work);
+}
+EXPORT_SYMBOL(ptp_cancel_worker_sync);
+
+/* module operations */
+
+static void __exit ptp_exit(void)
+{
+ class_destroy(ptp_class);
+ unregister_chrdev_region(ptp_devt, MINORMASK + 1);
+ ida_destroy(&ptp_clocks_map);
+}
+
+static int __init ptp_init(void)
+{
+ int err;
+
+ ptp_class = class_create(THIS_MODULE, "ptp");
+ if (IS_ERR(ptp_class)) {
+ pr_err("ptp: failed to allocate class\n");
+ return PTR_ERR(ptp_class);
+ }
+
+ err = alloc_chrdev_region(&ptp_devt, 0, MINORMASK + 1, "ptp");
+ if (err < 0) {
+ pr_err("ptp: failed to allocate device region\n");
+ goto no_region;
+ }
+
+ ptp_class->dev_groups = ptp_groups;
+ pr_info("PTP clock support registered\n");
+ return 0;
+
+no_region:
+ class_destroy(ptp_class);
+ return err;
+}
+
+subsys_initcall(ptp_init);
+module_exit(ptp_exit);
+
+MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");
+MODULE_DESCRIPTION("PTP clocks support");
+MODULE_LICENSE("GPL");