V4L/DVB (12399): mt9v011: Add support for controlling frame rates

Implement g_parm/s_parm ioctls. Those are used to check the current
frame rate (in fps) and to set it to a value. In practice, there are
only 15 possible different speeds, due to chip limits.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

diff --git a/drivers/media/video/mt9v011.c b/drivers/media/video/mt9v011.c
index c14bf47..8de1316 100644 (file)
--- a/drivers/media/video/mt9v011.c
+++ b/drivers/media/video/mt9v011.c
@@ -156,7 +156,7 @@ static void set_balance(struct v4l2_subdev *sd)
        mt9v011_write(sd, R2D_MT9V011_RED_GAIN, red_gain);
 }
 
-static void calc_fps(struct v4l2_subdev *sd)
+static void calc_fps(struct v4l2_subdev *sd, u32 *numerator, u32 *denominator)
 {
        struct mt9v011 *core = to_mt9v011(sd);
        unsigned height, width, hblank, vblank, speed;
@@ -179,6 +179,51 @@ static void calc_fps(struct v4l2_subdev *sd)
 
        v4l2_dbg(1, debug, sd, "Programmed to %u.%03u fps (%d pixel clcks)\n",
                tmp / 1000, tmp % 1000, t_time);
+
+       if (numerator && denominator) {
+               *numerator = 1000;
+               *denominator = (u32)frames_per_ms;
+       }
+}
+
+static u16 calc_speed(struct v4l2_subdev *sd, u32 numerator, u32 denominator)
+{
+       struct mt9v011 *core = to_mt9v011(sd);
+       unsigned height, width, hblank, vblank;
+       unsigned row_time, line_time;
+       u64 t_time, speed;
+
+       /* Avoid bogus calculus */
+       if (!numerator || !denominator)
+               return 0;
+
+       height = mt9v011_read(sd, R03_MT9V011_HEIGHT);
+       width = mt9v011_read(sd, R04_MT9V011_WIDTH);
+       hblank = mt9v011_read(sd, R05_MT9V011_HBLANK);
+       vblank = mt9v011_read(sd, R06_MT9V011_VBLANK);
+
+       row_time = width + 113 + hblank;
+       line_time = height + vblank + 1;
+
+       t_time = core->xtal * ((u64)numerator);
+       /* round to the closest value */
+       t_time += denominator / 2;
+       do_div(t_time, denominator);
+
+       speed = t_time;
+       do_div(speed, row_time * line_time);
+
+       /* Avoid having a negative value for speed */
+       if (speed < 2)
+               speed = 0;
+       else
+               speed -= 2;
+
+       /* Avoid speed overflow */
+       if (speed > 15)
+               return 15;
+
+       return (u16)speed;
 }
 
 static void set_res(struct v4l2_subdev *sd)
@@ -207,7 +252,7 @@ static void set_res(struct v4l2_subdev *sd)
        mt9v011_write(sd, R03_MT9V011_HEIGHT, core->height);
        mt9v011_write(sd, R06_MT9V011_VBLANK, 508 - core->height);
 
-       calc_fps(sd);
+       calc_fps(sd, NULL, NULL);
 };
 
 static int mt9v011_reset(struct v4l2_subdev *sd, u32 val)
@@ -322,6 +367,44 @@ static int mt9v011_try_fmt(struct v4l2_subdev *sd, struct v4l2_format *fmt)
        return 0;
 }
 
+static int mt9v011_g_parm(struct v4l2_subdev *sd, struct v4l2_streamparm *parms)
+{
+       struct v4l2_captureparm *cp = &parms->parm.capture;
+
+       if (parms->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
+               return -EINVAL;
+
+       memset(cp, 0, sizeof(struct v4l2_captureparm));
+       cp->capability = V4L2_CAP_TIMEPERFRAME;
+       calc_fps(sd,
+                &cp->timeperframe.numerator,
+                &cp->timeperframe.denominator);
+
+       return 0;
+}
+
+static int mt9v011_s_parm(struct v4l2_subdev *sd, struct v4l2_streamparm *parms)
+{
+       struct v4l2_captureparm *cp = &parms->parm.capture;
+       struct v4l2_fract *tpf = &cp->timeperframe;
+       u16 speed;
+
+       if (parms->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
+               return -EINVAL;
+       if (cp->extendedmode != 0)
+               return -EINVAL;
+
+       speed = calc_speed(sd, tpf->numerator, tpf->denominator);
+
+       mt9v011_write(sd, R0A_MT9V011_CLK_SPEED, speed);
+       v4l2_dbg(1, debug, sd, "Setting speed to %d\n", speed);
+
+       /* Recalculate and update fps info */
+       calc_fps(sd, &tpf->numerator, &tpf->denominator);
+
+       return 0;
+}
+
 static int mt9v011_s_fmt(struct v4l2_subdev *sd, struct v4l2_format *fmt)
 {
        struct v4l2_pix_format *pix = &fmt->fmt.pix;
@@ -419,6 +502,8 @@ static const struct v4l2_subdev_video_ops mt9v011_video_ops = {
        .enum_fmt = mt9v011_enum_fmt,
        .try_fmt = mt9v011_try_fmt,
        .s_fmt = mt9v011_s_fmt,
+       .g_parm = mt9v011_g_parm,
+       .s_parm = mt9v011_s_parm,
 };
 
 static const struct v4l2_subdev_ops mt9v011_ops = {