diff mbox

[7/8,media] staging: atomisp: convert timestamps to ktime_t

Message ID 20171127132027.1734806-7-arnd@arndb.de (mailing list archive)
State New, archived
Headers show

Commit Message

Arnd Bergmann Nov. 27, 2017, 1:19 p.m. UTC
timespec overflows in 2038 on 32-bit architectures, and the
getnstimeofday() suffers from possible time jumps, so the
timestamps here are better done using ktime_get(), which has
neither of those problems.

In case of ov2680, we don't seem to use the timestamp at
all, so I just remove it.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/staging/media/atomisp/i2c/ov2680.h                |  1 -
 drivers/staging/media/atomisp/i2c/ov5693/atomisp-ov5693.c | 15 ++++++---------
 drivers/staging/media/atomisp/i2c/ov5693/ov5693.h         |  2 +-
 3 files changed, 7 insertions(+), 11 deletions(-)

Comments

Andy Shevchenko Nov. 27, 2017, 3:05 p.m. UTC | #1
On Mon, 2017-11-27 at 14:19 +0100, Arnd Bergmann wrote:
> timespec overflows in 2038 on 32-bit architectures, and the
> getnstimeofday() suffers from possible time jumps, so the
> timestamps here are better done using ktime_get(), which has
> neither of those problems.
> 
> In case of ov2680, we don't seem to use the timestamp at
> all, so I just remove it.
> 

> +	ktime_t timedelay = ns_to_ktime(
>  		min((u32)abs(dev->number_of_steps) *
> DELAY_PER_STEP_NS,
> -		(u32)DELAY_MAX_PER_STEP_NS),
> -	};
> +		    (u32)DELAY_MAX_PER_STEP_NS));

Since you are touching this, it might make sense to convert to

min_t(u32, ...)

...and locate lines something like:

ktime_t timeday = ns_to_ktime(min_t(u32,
     param1,
     param2));

From my pov will make readability better.
Arnd Bergmann Nov. 27, 2017, 3:20 p.m. UTC | #2
On Mon, Nov 27, 2017 at 4:05 PM, Andy Shevchenko
<andriy.shevchenko@linux.intel.com> wrote:
> On Mon, 2017-11-27 at 14:19 +0100, Arnd Bergmann wrote:
>> timespec overflows in 2038 on 32-bit architectures, and the
>> getnstimeofday() suffers from possible time jumps, so the
>> timestamps here are better done using ktime_get(), which has
>> neither of those problems.
>>
>> In case of ov2680, we don't seem to use the timestamp at
>> all, so I just remove it.
>>
>
>> +     ktime_t timedelay = ns_to_ktime(
>>               min((u32)abs(dev->number_of_steps) *
>> DELAY_PER_STEP_NS,
>> -             (u32)DELAY_MAX_PER_STEP_NS),
>> -     };
>> +                 (u32)DELAY_MAX_PER_STEP_NS));
>
> Since you are touching this, it might make sense to convert to
>
> min_t(u32, ...)
>
> ...and locate lines something like:
>
> ktime_t timeday = ns_to_ktime(min_t(u32,
>      param1,
>      param2));
>
> From my pov will make readability better.

Yes, good idea. Re-sending the patch now. Thanks for taking a look,

      Arnd
diff mbox

Patch

diff --git a/drivers/staging/media/atomisp/i2c/ov2680.h b/drivers/staging/media/atomisp/i2c/ov2680.h
index bf4897347df7..03f75dd80f87 100644
--- a/drivers/staging/media/atomisp/i2c/ov2680.h
+++ b/drivers/staging/media/atomisp/i2c/ov2680.h
@@ -174,7 +174,6 @@  struct ov2680_format {
 		struct mutex input_lock;
 	struct v4l2_ctrl_handler ctrl_handler;
 		struct camera_sensor_platform_data *platform_data;
-		struct timespec timestamp_t_focus_abs;
 		int vt_pix_clk_freq_mhz;
 		int fmt_idx;
 		int run_mode;
diff --git a/drivers/staging/media/atomisp/i2c/ov5693/atomisp-ov5693.c b/drivers/staging/media/atomisp/i2c/ov5693/atomisp-ov5693.c
index 3e7c3851280f..a715ea0e4230 100644
--- a/drivers/staging/media/atomisp/i2c/ov5693/atomisp-ov5693.c
+++ b/drivers/staging/media/atomisp/i2c/ov5693/atomisp-ov5693.c
@@ -973,7 +973,7 @@  static int ov5693_t_focus_abs(struct v4l2_subdev *sd, s32 value)
 	if (ret == 0) {
 		dev->number_of_steps = value - dev->focus;
 		dev->focus = value;
-		getnstimeofday(&(dev->timestamp_t_focus_abs));
+		dev->timestamp_t_focus_abs = ktime_get();
 	} else
 		dev_err(&client->dev,
 			"%s: i2c failed. ret %d\n", __func__, ret);
@@ -993,16 +993,13 @@  static int ov5693_q_focus_status(struct v4l2_subdev *sd, s32 *value)
 {
 	u32 status = 0;
 	struct ov5693_device *dev = to_ov5693_sensor(sd);
-	struct timespec temptime;
-	const struct timespec timedelay = {
-		0,
+	ktime_t temptime;
+	ktime_t timedelay = ns_to_ktime(
 		min((u32)abs(dev->number_of_steps) * DELAY_PER_STEP_NS,
-		(u32)DELAY_MAX_PER_STEP_NS),
-	};
+		    (u32)DELAY_MAX_PER_STEP_NS));
 
-	getnstimeofday(&temptime);
-	temptime = timespec_sub(temptime, (dev->timestamp_t_focus_abs));
-	if (timespec_compare(&temptime, &timedelay) <= 0) {
+	temptime = ktime_sub(ktime_get(), (dev->timestamp_t_focus_abs));
+	if (ktime_compare(temptime, timedelay) <= 0) {
 		status |= ATOMISP_FOCUS_STATUS_MOVING;
 		status |= ATOMISP_FOCUS_HP_IN_PROGRESS;
 	} else {
diff --git a/drivers/staging/media/atomisp/i2c/ov5693/ov5693.h b/drivers/staging/media/atomisp/i2c/ov5693/ov5693.h
index 2ea63807c56d..68cfcb4a6c3c 100644
--- a/drivers/staging/media/atomisp/i2c/ov5693/ov5693.h
+++ b/drivers/staging/media/atomisp/i2c/ov5693/ov5693.h
@@ -221,7 +221,7 @@  struct ov5693_device {
 	struct v4l2_ctrl_handler ctrl_handler;
 
 	struct camera_sensor_platform_data *platform_data;
-	struct timespec timestamp_t_focus_abs;
+	ktime_t timestamp_t_focus_abs;
 	int vt_pix_clk_freq_mhz;
 	int fmt_idx;
 	int run_mode;