To get the link frequency value, or to calculate a parameter depending on
it the receiver driver should use V4L2_CID_LINK_FREQ. If V4L2_CID_LINK_FREQ
control is not implemented in the remote subdevice, the link frequency
can be calculated from V4L2_CID_PIXEL_RATE control value. But the latter
may not give the correct link frequency, and should only be used as the
last resort. v4l2_get_link_freq() does exactly that, so use it instead
of reading V4L2_CID_PIXEL_RATE directly.
Signed-off-by: Andrey Konovalov <andrey.konovalov@xxxxxxxxxx>
---
drivers/media/platform/rcar-vin/rcar-csi2.c | 18 +++++++-----------
1 file changed, 7 insertions(+), 11 deletions(-)
diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
index e06cd512aba2..eec8f9dd9060 100644
--- a/drivers/media/platform/rcar-vin/rcar-csi2.c
+++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
@@ -455,29 +455,25 @@ static int rcsi2_calc_mbps(struct rcar_csi2 *priv, unsigned int bpp,
unsigned int lanes)
{
struct v4l2_subdev *source;
- struct v4l2_ctrl *ctrl;
- u64 mbps;
+ s64 mbps;
if (!priv->remote)
return -ENODEV;
source = priv->remote;
- /* Read the pixel rate control from remote. */
- ctrl = v4l2_ctrl_find(source->ctrl_handler, V4L2_CID_PIXEL_RATE);
- if (!ctrl) {
- dev_err(priv->dev, "no pixel rate control in subdev %s\n",
+ /* Read the link frequency from the remote subdev. */
+ mbps = v4l2_get_link_freq(source->ctrl_handler, bpp, 2 * lanes);
+ if (mbps < 0) {
+ dev_err(priv->dev, "failed to get link rate from subdev %s\n",
source->name);
- return -EINVAL;
+ return mbps;
}
-
/*
* Calculate the phypll in mbps.
- * link_freq = (pixel_rate * bits_per_sample) / (2 * nr_of_lanes)
* bps = link_freq * 2
*/
- mbps = v4l2_ctrl_g_ctrl_int64(ctrl) * bpp;
- do_div(mbps, lanes * 1000000);
+ do_div(mbps, 1000000 / 2);
return mbps;
}
--
2.17.1
