[PATCH 2/2] PTP: add support for one-shot output

[Felipe Balbi <felipe.balbi@linux.intel.com>]

Some controllers allow for a one-shot output pulse, in contrast to
periodic output. Now that we have extensible versions of our IOCTLs, we
can finally make use of the 'flags' field to pass a bit telling driver
that if we want one-shot pulse output.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
---
 drivers/ptp/ptp_chardev.c      | 5 ++---
 include/uapi/linux/ptp_clock.h | 4 +++-
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/ptp/ptp_chardev.c b/drivers/ptp/ptp_chardev.c
index 204212fc3f8c..b75a65880056 100644
--- a/drivers/ptp/ptp_chardev.c
+++ b/drivers/ptp/ptp_chardev.c
@@ -173,9 +173,8 @@ long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
 			err = -EFAULT;
 			break;
 		}
-		if ((req.perout.flags || req.perout.rsv[0] || req.perout.rsv[1]
-				|| req.perout.rsv[2] || req.perout.rsv[3])
-			&& cmd == PTP_PEROUT_REQUEST2) {
+		if ((req.perout.rsv[0] || req.perout.rsv[1] || req.perout.rsv[2]
+			|| req.perout.rsv[3]) && cmd == PTP_PEROUT_REQUEST2) {
 			err = -EINVAL;
 			break;
 		} else if (cmd == PTP_PEROUT_REQUEST) {
diff --git a/include/uapi/linux/ptp_clock.h b/include/uapi/linux/ptp_clock.h
index 039cd62ec706..9412b16cc8ed 100644
--- a/include/uapi/linux/ptp_clock.h
+++ b/include/uapi/linux/ptp_clock.h
@@ -67,7 +67,9 @@ struct ptp_perout_request {
 	struct ptp_clock_time start;  /* Absolute start time. */
 	struct ptp_clock_time period; /* Desired period, zero means disable. */
 	unsigned int index;           /* Which channel to configure. */
-	unsigned int flags;           /* Reserved for future use. */
+
+#define PTP_PEROUT_ONE_SHOT BIT(0)
+	unsigned int flags;           /* Bit 0 -> oneshot output. */
 	unsigned int rsv[4];          /* Reserved for future use. */
 };
 
-- 
2.22.0