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[25/35] media: venus: Use the correct div_ function

Message ID 20240415-fix-cocci-v1-25-477afb23728b@chromium.org
State New
Headers show
Series media: Fix coccinelle warning/errors | expand

Commit Message

Ricardo Ribalda April 15, 2024, 7:34 p.m. UTC
us_per_frame does not fit in u32

Found with cocci:
drivers/media/platform/qcom/venus/venc.c:418:1-7: WARNING: do_div() does a 64-by-32 division, please consider using div64_u64 instead.

Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
---
 drivers/media/platform/qcom/venus/venc.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

Comments

Dan Carpenter April 17, 2024, 8:36 a.m. UTC | #1
On Mon, Apr 15, 2024 at 07:34:42PM +0000, Ricardo Ribalda wrote:
> us_per_frame does not fit in u32
> 

drivers/media/platform/qcom/venus/venc.c
   391  static int venc_s_parm(struct file *file, void *fh, struct v4l2_streamparm *a)
   392  {
   393          struct venus_inst *inst = to_inst(file);
   394          struct v4l2_outputparm *out = &a->parm.output;
   395          struct v4l2_fract *timeperframe = &out->timeperframe;
   396          u64 us_per_frame, fps;
   397  
   398          if (a->type != V4L2_BUF_TYPE_VIDEO_OUTPUT &&
   399              a->type != V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE)
   400                  return -EINVAL;
   401  
   402          memset(out->reserved, 0, sizeof(out->reserved));
   403  
   404          if (!timeperframe->denominator)
   405                  timeperframe->denominator = inst->timeperframe.denominator;
   406          if (!timeperframe->numerator)
   407                  timeperframe->numerator = inst->timeperframe.numerator;
   408  
   409          out->capability = V4L2_CAP_TIMEPERFRAME;
   410  
   411          us_per_frame = timeperframe->numerator * (u64)USEC_PER_SEC;
                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
It looks like in some drivers this multiply can go over U32_MAX.

   412          do_div(us_per_frame, timeperframe->denominator);
                       ^^^^^^^^^^^^
But after this divide, then we're under 1,000,000 again.  Otherwise the
FPS is zero.  So maybe the right thing to do is:

	inst->fps = USEC_PER_SEC / (u32)us_per_frame;

   413  
   414          if (!us_per_frame)
   415                  return -EINVAL;
   416  
   417          fps = (u64)USEC_PER_SEC;
   418          do_div(fps, us_per_frame);
   419  
   420          inst->timeperframe = *timeperframe;
   421          inst->fps = fps;
   422  
   423          return 0;
   424  }

regards,
dan carpenter
diff mbox series

Patch

diff --git a/drivers/media/platform/qcom/venus/venc.c b/drivers/media/platform/qcom/venus/venc.c
index 3ec2fb8d9fab..de06e1712d09 100644
--- a/drivers/media/platform/qcom/venus/venc.c
+++ b/drivers/media/platform/qcom/venus/venc.c
@@ -393,7 +393,7 @@  static int venc_s_parm(struct file *file, void *fh, struct v4l2_streamparm *a)
 	struct venus_inst *inst = to_inst(file);
 	struct v4l2_outputparm *out = &a->parm.output;
 	struct v4l2_fract *timeperframe = &out->timeperframe;
-	u64 us_per_frame, fps;
+	u64 us_per_frame;
 
 	if (a->type != V4L2_BUF_TYPE_VIDEO_OUTPUT &&
 	    a->type != V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE)
@@ -414,11 +414,8 @@  static int venc_s_parm(struct file *file, void *fh, struct v4l2_streamparm *a)
 	if (!us_per_frame)
 		return -EINVAL;
 
-	fps = (u64)USEC_PER_SEC;
-	do_div(fps, us_per_frame);
-
+	inst->fps = div64_u64(USEC_PER_SEC, us_per_frame);
 	inst->timeperframe = *timeperframe;
-	inst->fps = fps;
 
 	return 0;
 }