Re: [PATCH v6 6/6] media: venus: vdec: Make the range of us_per_frame explicit

From: Bryan O'Donoghue
Date: Tue Jan 14 2025 - 20:17:30 EST


On 11/01/2025 09:55, Ricardo Ribalda wrote:
Fps bigger than 0.000232829 fps, this fits in a 32 bit us_per_frame.
There is no need to do a 64 bit division here.
Also, the driver only works with whole fps.

Found by cocci:
drivers/media/platform/qcom/venus/vdec.c:488:1-7: WARNING: do_div() does a 64-by-32 division, please consider using div64_u64 instead.

Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@xxxxxxxxxx>
Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
---
drivers/media/platform/qcom/venus/vdec.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/media/platform/qcom/venus/vdec.c b/drivers/media/platform/qcom/venus/vdec.c
index e160a5508154..aa9ba38186b8 100644
--- a/drivers/media/platform/qcom/venus/vdec.c
+++ b/drivers/media/platform/qcom/venus/vdec.c
@@ -484,8 +484,7 @@ static int vdec_s_parm(struct file *file, void *fh, struct v4l2_streamparm *a)
do_div(us_per_frame, timeperframe->denominator);
us_per_frame = max(USEC_PER_SEC, us_per_frame);
- fps = (u64)USEC_PER_SEC;
- do_div(fps, us_per_frame);
+ fps = USEC_PER_SEC / (u32)us_per_frame;
fps = min(VENUS_MAX_FPS, fps);
inst->fps = fps;


Tested-by: Bryan O'Donoghue <bryan.odonoghue@xxxxxxxxxx> # qrb5615-rb5
Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@xxxxxxxxxx>