On 7/16/20 2:18 PM, Dmitry Osipenko wrote:
17.07.2020 00:09, Sowjanya Komatineni пишет:
On 7/16/20 1:38 PM, Dmitry Osipenko wrote:
15.07.2020 07:20, Sowjanya Komatineni пишет:
SW can trigger MIPI pads calibration any time after power on
but calibration results will be latched and applied to the pads
by MIPI CAL unit only when the link is in LP-11 state and then
status register will be updated.
For CSI, trigger of pads calibration happen during CSI stream
enable where CSI receiver is kept ready prior to sensor or CSI
transmitter stream start.
So, pads may not be in LP-11 at this time and waiting for the
calibration to be done immediate after calibration start will
result in timeout.
This patch splits tegra_mipi_calibrate() and tegra_mipi_wait()
so triggering for calibration and waiting for it to complete can
happen at different stages.
Signed-off-by: Sowjanya Komatineni <skomatineni@xxxxxxxxxx>
---
...
int tegra_mipi_calibrate(struct tegra_mipi_device *device)
{
@@ -370,12 +381,10 @@ int tegra_mipi_calibrate(struct
tegra_mipi_device *device)
value |= MIPI_CAL_CTRL_START;
tegra_mipi_writel(device->mipi, value, MIPI_CAL_CTRL);
- err = tegra_mipi_wait(device->mipi);
Doesn't MIPI clock need to be enabled during of the calibration process?
MIPI clock is already enabled in tegra_mipi_calibrate
mutex_unlock(&device->mipi->lock);
clk_disable(device->mipi->clk);
What keeps MIPI clock enabled after completion of the
tegra_mipi_calibrate() invocation?
MIPI clock is disabled at end of tegra_mipi_calibrate and is re-enabled
during tegra_mipi_wait.
I think I should fix this to keep the clock enabled till calibration
results are latched.
All consumers of tegra_mipi_calibrate() will call tegra_mipi_wait().
So will remove clk_disable mipi clk at end of tegra_mipi_calibrate() and
clk_enable mipi_clk at beginning of tegra_mipi_wait()
- return err;
+ return 0;
}
EXPORT_SYMBOL(tegra_mipi_calibrate);
