1 files changed, 71 insertions, 0 deletions
diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-timestamp.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-timestamp.c
new file mode 100644
index 000000000000..ed3169274d24
--- /dev/null
+++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-timestamp.c
@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// mcp251xfd - Microchip MCP251xFD Family CAN controller driver
+//
+// Copyright (c) 2021 Pengutronix,
+//               Marc Kleine-Budde <kernel@pengutronix.de>
+//
+
+#include <linux/clocksource.h>
+#include <linux/workqueue.h>
+
+#include "mcp251xfd.h"
+
+static u64 mcp251xfd_timestamp_read(const struct cyclecounter *cc)
+{
+	struct mcp251xfd_priv *priv;
+	u32 timestamp = 0;
+	int err;
+
+	priv = container_of(cc, struct mcp251xfd_priv, cc);
+	err = mcp251xfd_get_timestamp(priv, &timestamp);
+	if (err)
+		netdev_err(priv->ndev,
+			   "Error %d while reading timestamp. HW timestamps may be inaccurate.",
+			   err);
+
+	return timestamp;
+}
+
+static void mcp251xfd_timestamp_work(struct work_struct *work)
+{
+	struct delayed_work *delayed_work = to_delayed_work(work);
+	struct mcp251xfd_priv *priv;
+
+	priv = container_of(delayed_work, struct mcp251xfd_priv, timestamp);
+	timecounter_read(&priv->tc);
+
+	schedule_delayed_work(&priv->timestamp,
+			      MCP251XFD_TIMESTAMP_WORK_DELAY_SEC * HZ);
+}
+
+void mcp251xfd_skb_set_timestamp(struct mcp251xfd_priv *priv,
+				 struct sk_buff *skb, u32 timestamp)
+{
+	struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
+	u64 ns;
+
+	ns = timecounter_cyc2time(&priv->tc, timestamp);
+	hwtstamps->hwtstamp = ns_to_ktime(ns);
+}
+
+void mcp251xfd_timestamp_init(struct mcp251xfd_priv *priv)
+{
+	struct cyclecounter *cc = &priv->cc;
+
+	cc->read = mcp251xfd_timestamp_read;
+	cc->mask = CYCLECOUNTER_MASK(32);
+	cc->shift = 1;
+	cc->mult = clocksource_hz2mult(priv->can.clock.freq, cc->shift);
+
+	timecounter_init(&priv->tc, &priv->cc, ktime_get_real_ns());
+
+	INIT_DELAYED_WORK(&priv->timestamp, mcp251xfd_timestamp_work);
+	schedule_delayed_work(&priv->timestamp,
+			      MCP251XFD_TIMESTAMP_WORK_DELAY_SEC * HZ);
+}
+
+void mcp251xfd_timestamp_stop(struct mcp251xfd_priv *priv)
+{
+	cancel_delayed_work_sync(&priv->timestamp);
+}