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Message-Id: <20171103163220.3799742-2-arnd@arndb.de>
Date: Fri, 3 Nov 2017 17:31:37 +0100
From: Arnd Bergmann <arnd@...db.de>
To: Wolfgang Grandegger <wg@...ndegger.com>,
Marc Kleine-Budde <mkl@...gutronix.de>
Cc: Arnd Bergmann <arnd@...db.de>,
Stephane Grosjean <s.grosjean@...k-system.com>,
추지호 <jiho.chu@...sung.com>,
Johan Hovold <johan@...nel.org>, linux-can@...r.kernel.org,
netdev@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: [PATCH 2/2] can: peak_usb: use ktime_t consistently
This changes the calculation of the timestamps to use ktime_t
instead of struct timeval as the base. This gets rid of one
of the few remaining users of the deprecated ktime_to_timeval()
and timeval_to_ktime() helpers.
The code should also get more efficient, as we have now removed
all of the divisions.
I have left the cut-off for resetting the counters as 4.200
seconds, in order to leave the behavior unchanged otherwise.
Signed-off-by: Arnd Bergmann <arnd@...db.de>
---
drivers/net/can/usb/peak_usb/pcan_usb_core.c | 46 +++++++++-------------------
drivers/net/can/usb/peak_usb/pcan_usb_core.h | 2 +-
2 files changed, 15 insertions(+), 33 deletions(-)
diff --git a/drivers/net/can/usb/peak_usb/pcan_usb_core.c b/drivers/net/can/usb/peak_usb/pcan_usb_core.c
index 695a75a9b4bb..8f699ee6a528 100644
--- a/drivers/net/can/usb/peak_usb/pcan_usb_core.c
+++ b/drivers/net/can/usb/peak_usb/pcan_usb_core.c
@@ -80,21 +80,6 @@ void peak_usb_init_time_ref(struct peak_time_ref *time_ref,
}
}
-static void peak_usb_add_us(struct timeval *tv, u32 delta_us)
-{
- /* number of s. to add to final time */
- u32 delta_s = delta_us / 1000000;
-
- delta_us -= delta_s * 1000000;
-
- tv->tv_usec += delta_us;
- if (tv->tv_usec >= 1000000) {
- tv->tv_usec -= 1000000;
- delta_s++;
- }
- tv->tv_sec += delta_s;
-}
-
/*
* sometimes, another now may be more recent than current one...
*/
@@ -103,7 +88,7 @@ void peak_usb_update_ts_now(struct peak_time_ref *time_ref, u32 ts_now)
time_ref->ts_dev_2 = ts_now;
/* should wait at least two passes before computing */
- if (time_ref->tv_host.tv_sec > 0) {
+ if (ktime_to_ns(time_ref->tv_host) > 0) {
u32 delta_ts = time_ref->ts_dev_2 - time_ref->ts_dev_1;
if (time_ref->ts_dev_2 < time_ref->ts_dev_1)
@@ -118,26 +103,26 @@ void peak_usb_update_ts_now(struct peak_time_ref *time_ref, u32 ts_now)
*/
void peak_usb_set_ts_now(struct peak_time_ref *time_ref, u32 ts_now)
{
- if (time_ref->tv_host_0.tv_sec == 0) {
+ if (ktime_to_ns(time_ref->tv_host_0) == 0) {
/* use monotonic clock to correctly compute further deltas */
- time_ref->tv_host_0 = ktime_to_timeval(ktime_get());
- time_ref->tv_host.tv_sec = 0;
+ time_ref->tv_host_0 = ktime_get();
+ time_ref->tv_host = ktime_set(0, 0);
} else {
/*
- * delta_us should not be >= 2^32 => delta_s should be < 4294
+ * delta_us should not be >= 2^32 => delta should be < 4294s
* handle 32-bits wrapping here: if count of s. reaches 4200,
* reset counters and change time base
*/
- if (time_ref->tv_host.tv_sec != 0) {
- u32 delta_s = time_ref->tv_host.tv_sec
- - time_ref->tv_host_0.tv_sec;
- if (delta_s > 4200) {
+ if (ktime_to_ns(time_ref->tv_host)) {
+ ktime_t delta = ktime_sub(time_ref->tv_host,
+ time_ref->tv_host_0);
+ if (ktime_to_ns(delta) > (4200ull * NSEC_PER_SEC)) {
time_ref->tv_host_0 = time_ref->tv_host;
time_ref->ts_total = 0;
}
}
- time_ref->tv_host = ktime_to_timeval(ktime_get());
+ time_ref->tv_host = ktime_get();
time_ref->tick_count++;
}
@@ -146,13 +131,12 @@ void peak_usb_set_ts_now(struct peak_time_ref *time_ref, u32 ts_now)
}
/*
- * compute timeval according to current ts and time_ref data
+ * compute time according to current ts and time_ref data
*/
void peak_usb_get_ts_time(struct peak_time_ref *time_ref, u32 ts, ktime_t *time)
{
- /* protect from getting timeval before setting now */
- if (time_ref->tv_host.tv_sec > 0) {
- struct timeval tv;
+ /* protect from getting time before setting now */
+ if (ktime_to_ns(time_ref->tv_host)) {
u64 delta_us;
delta_us = ts - time_ref->ts_dev_2;
@@ -164,9 +148,7 @@ void peak_usb_get_ts_time(struct peak_time_ref *time_ref, u32 ts, ktime_t *time)
delta_us *= time_ref->adapter->us_per_ts_scale;
delta_us >>= time_ref->adapter->us_per_ts_shift;
- tv = time_ref->tv_host_0;
- peak_usb_add_us(&tv, (u32)delta_us);
- *time = timeval_to_ktime(tv);
+ *time = ktime_add_us(time_ref->tv_host_0, delta_us);
} else {
*time = ktime_get();
}
diff --git a/drivers/net/can/usb/peak_usb/pcan_usb_core.h b/drivers/net/can/usb/peak_usb/pcan_usb_core.h
index b9a221ea7e5c..29f03dccca10 100644
--- a/drivers/net/can/usb/peak_usb/pcan_usb_core.h
+++ b/drivers/net/can/usb/peak_usb/pcan_usb_core.h
@@ -96,7 +96,7 @@ extern const struct peak_usb_adapter pcan_usb_pro_fd;
extern const struct peak_usb_adapter pcan_usb_x6;
struct peak_time_ref {
- struct timeval tv_host_0, tv_host;
+ ktime_t tv_host_0, tv_host;
u32 ts_dev_1, ts_dev_2;
u64 ts_total;
u32 tick_count;
--
2.9.0
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