[RFC PATCH 3/5] PTP: implement PTP_EVENT_COUNT_TSTAMP ioctl

[Felipe Balbi]

With this, we can request the underlying driver to count the number of
events that have been captured.

Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
---
 drivers/ptp/ptp_chardev.c      | 15 +++++++++++++++
 include/uapi/linux/ptp_clock.h |  2 ++
 2 files changed, 17 insertions(+)

diff --git a/drivers/ptp/ptp_chardev.c b/drivers/ptp/ptp_chardev.c
index 18ffe449efdf..a3e163a6acdc 100644
--- a/drivers/ptp/ptp_chardev.c
+++ b/drivers/ptp/ptp_chardev.c
@@ -114,6 +114,7 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
 	struct system_device_crosststamp xtstamp;
 	struct ptp_clock_info *ops = ptp->info;
 	struct ptp_sys_offset *sysoff = NULL;
+	struct ptp_event_count_tstamp counttstamp;
 	struct ptp_system_timestamp sts;
 	struct ptp_clock_request req;
 	struct ptp_clock_caps caps;
@@ -301,6 +302,20 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
 		mutex_unlock(&ptp->pincfg_mux);
 		break;
 
+	case PTP_EVENT_COUNT_TSTAMP:
+		if (!ops->counttstamp)
+			return -ENOTSUPP;
+		if (copy_from_user(&req.perout, (void __user *)arg,
+				   sizeof(counttstamp))) {
+			err = -EFAULT;
+			break;
+		}
+		err = ops->counttstamp(ops, &counttstamp);
+		if (!err && copy_to_user((void __user *)arg, &counttstamp,
+						sizeof(counttstamp)))
+			err = -EFAULT;
+		break;
+
 	default:
 		err = -ENOTTY;
 		break;
diff --git a/include/uapi/linux/ptp_clock.h b/include/uapi/linux/ptp_clock.h
index 1bc794ad957a..674db7de64f3 100644
--- a/include/uapi/linux/ptp_clock.h
+++ b/include/uapi/linux/ptp_clock.h
@@ -148,6 +148,8 @@ struct ptp_pin_desc {
 	_IOWR(PTP_CLK_MAGIC, 8, struct ptp_sys_offset_precise)
 #define PTP_SYS_OFFSET_EXTENDED \
 	_IOWR(PTP_CLK_MAGIC, 9, struct ptp_sys_offset_extended)
+#define PTP_EVENT_COUNT_TSTAMP \
+	_IOWR(PTP_CLK_MAGIC, 6, struct ptp_event_count_tstamp)
 
 struct ptp_extts_event {
 	struct ptp_clock_time t; /* Time event occured. */
-- 
2.22.0