On 7/31/20 4:39 AM, Dmitry Osipenko wrote:
31.07.2020 12:02, Sowjanya Komatineni пишет:
...
@@ -249,13 +249,47 @@ static int tegra_csi_enable_stream(struct v4l2_subdev *subdev)
return ret;
}
+ if (csi_chan->mipi) {
+ ret = tegra_mipi_enable(csi_chan->mipi);
+ if (ret < 0) {
+ dev_err(csi->dev,
+ "failed to enable MIPI pads: %d\n", ret);
+ goto rpm_put;
+ }
+
+ /*
+ * CSI MIPI pads PULLUP, PULLDN and TERM impedances need to
+ * be calibrated after power on.
+ * So, trigger the calibration start here and results will
+ * be latched and applied to the pads when link is in LP11
+ * state during start of sensor streaming.
+ */
+ ret = tegra_mipi_start_calibration(csi_chan->mipi);
+ if (ret < 0) {
+ dev_err(csi->dev,
+ "failed to start MIPI calibration: %d\n", ret);
+ goto disable_mipi;
+ }
What would happen if CSI stream is enabled and then immediately disabled
without enabling camera sensor?
Nothing will happen as during stream enable csi receiver is kept ready.
But actual capture will not happen during that point.
+ }
+
...
static int tegra_channel_enable_stream(struct tegra_vi_channel *chan)
{
struct v4l2_subdev *csi_subdev, *src_subdev;
+ struct tegra_csi_channel *csi_chan;
int ret;
/*
@@ -206,13 +207,30 @@ static int tegra_channel_enable_stream(struct tegra_vi_channel *chan)
if (IS_ENABLED(CONFIG_VIDEO_TEGRA_TPG))
return 0;
+ csi_chan = v4l2_get_subdevdata(csi_subdev);
+ /*
+ * TRM has incorrectly documented to wait for done status from
+ * calibration logic after CSI interface power on.
+ * As per the design, calibration results are latched and applied
+ * to the pads only when the link is in LP11 state which will happen
+ * during the sensor stream-on.
+ * CSI subdev stream-on triggers start of MIPI pads calibration.
+ * Wait for calibration to finish here after sensor subdev stream-on
+ * and in case of sensor stream-on failure, cancel the calibration.
+ */
src_subdev = tegra_channel_get_remote_source_subdev(chan);
Is it possible to move the start_calibration() here?
I think we can do start here as well I guess but currently I am
following steps order as per design document.
This is the reason I have updated in above comment as well.
ret = v4l2_subdev_call(src_subdev, video, s_stream, true);
if (ret < 0 && ret != -ENOIOCTLCMD) {
+ tegra_mipi_cancel_calibration(csi_chan->mipi);
v4l2_subdev_call(csi_subdev, video, s_stream, false);
return ret;
}
+ ret = tegra_mipi_finish_calibration(csi_chan->mipi);
+ if (ret < 0)
+ dev_warn(csi_chan->csi->dev,
+ "MIPI calibration failed: %d\n", ret);
+
return 0;
}
