From: Kirill Smelkov <kirr@mns.spb.ru>
Date: Mon, 22 Oct 2012 17:14:01 +0000 (-0300)
Subject: [media] v4l2: Fix typo in struct v4l2_captureparm description
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=2e74598d7f4c6d1b34da84037d9a7f8b1c8e04ae;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git

[media] v4l2: Fix typo in struct v4l2_captureparm description

Judging from what drivers do and from my experience temeperframe
fraction is set in seconds - look e.g. here
    static int bttv_g_parm(struct file *file, void *f,
                                    struct v4l2_streamparm *parm)
    {
            struct bttv_fh *fh = f;
            struct bttv *btv = fh->btv;
            v4l2_video_std_frame_period(bttv_tvnorms[btv->tvnorm].v4l2_id,
                                        &parm->parm.capture.timeperframe);
    ...
    void v4l2_video_std_frame_period(int id, struct v4l2_fract *frameperiod)
    {
            if (id & V4L2_STD_525_60) {
                    frameperiod->numerator = 1001;
                    frameperiod->denominator = 30000;
            } else {
                    frameperiod->numerator = 1;
                    frameperiod->denominator = 25;
            }
and also v4l2-ctl in userspace decodes this as seconds:
    if (doioctl(fd, VIDIOC_G_PARM, &parm, "VIDIOC_G_PARM") == 0) {
            const struct v4l2_fract &tf = parm.parm.capture.timeperframe;
            ...
            printf("\tFrames per second: %.3f (%d/%d)\n",
                            (1.0 * tf.denominator) / tf.numerator,
                            tf.denominator, tf.numerator);
The typo was there from day 1 - added in 2002 in e028b61b ([PATCH]
add v4l2 api)(*)
(*) found in history tree
    git://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git

Signed-off-by: Kirill Smelkov <kirr@mns.spb.ru>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
---

diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index 57bfa59cda74..2fff7ff3e05b 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -737,7 +737,7 @@ struct v4l2_window {
 struct v4l2_captureparm {
 	__u32		   capability;	  /*  Supported modes */
 	__u32		   capturemode;	  /*  Current mode */
-	struct v4l2_fract  timeperframe;  /*  Time per frame in .1us units */
+	struct v4l2_fract  timeperframe;  /*  Time per frame in seconds */
 	__u32		   extendedmode;  /*  Driver-specific extensions */
 	__u32              readbuffers;   /*  # of buffers for read */
 	__u32		   reserved[4];