1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // mcp251xfd - Microchip MCP251xFD Family CAN controller driver
4 //
5 // Copyright (c) 2021, 2023 Pengutronix,
6 // Marc Kleine-Budde <kernel@pengutronix.de>
7 //
8
9 #include <linux/clocksource.h>
10 #include <linux/workqueue.h>
11
12 #include "mcp251xfd.h"
13
mcp251xfd_timestamp_raw_read(const struct cyclecounter * cc)14 static u64 mcp251xfd_timestamp_raw_read(const struct cyclecounter *cc)
15 {
16 const struct mcp251xfd_priv *priv;
17 u32 ts_raw = 0;
18 int err;
19
20 priv = container_of(cc, struct mcp251xfd_priv, cc);
21 err = mcp251xfd_get_timestamp_raw(priv, &ts_raw);
22 if (err)
23 netdev_err(priv->ndev,
24 "Error %d while reading timestamp. HW timestamps may be inaccurate.",
25 err);
26
27 return ts_raw;
28 }
29
mcp251xfd_timestamp_work(struct work_struct * work)30 static void mcp251xfd_timestamp_work(struct work_struct *work)
31 {
32 struct delayed_work *delayed_work = to_delayed_work(work);
33 struct mcp251xfd_priv *priv;
34
35 priv = container_of(delayed_work, struct mcp251xfd_priv, timestamp);
36 timecounter_read(&priv->tc);
37
38 schedule_delayed_work(&priv->timestamp,
39 MCP251XFD_TIMESTAMP_WORK_DELAY_SEC * HZ);
40 }
41
mcp251xfd_timestamp_init(struct mcp251xfd_priv * priv)42 void mcp251xfd_timestamp_init(struct mcp251xfd_priv *priv)
43 {
44 struct cyclecounter *cc = &priv->cc;
45
46 cc->read = mcp251xfd_timestamp_raw_read;
47 cc->mask = CYCLECOUNTER_MASK(32);
48 cc->shift = 1;
49 cc->mult = clocksource_hz2mult(priv->can.clock.freq, cc->shift);
50
51 INIT_DELAYED_WORK(&priv->timestamp, mcp251xfd_timestamp_work);
52 }
53
mcp251xfd_timestamp_start(struct mcp251xfd_priv * priv)54 void mcp251xfd_timestamp_start(struct mcp251xfd_priv *priv)
55 {
56 timecounter_init(&priv->tc, &priv->cc, ktime_get_real_ns());
57 schedule_delayed_work(&priv->timestamp,
58 MCP251XFD_TIMESTAMP_WORK_DELAY_SEC * HZ);
59 }
60
mcp251xfd_timestamp_stop(struct mcp251xfd_priv * priv)61 void mcp251xfd_timestamp_stop(struct mcp251xfd_priv *priv)
62 {
63 cancel_delayed_work_sync(&priv->timestamp);
64 }
65