Re: [PATCH v9 08/10] gpu: host1x: mipi: Keep MIPI clock enabled and mutex locked till calibration done

Dmitry Osipenko
2020-08-07T02:31:37Z

06.08.2020 22:01, Sowjanya Komatineni пишет:
...
> +int tegra_mipi_start_calibration(struct tegra_mipi_device *device)
> {
> const struct tegra_mipi_soc *soc = device->mipi->soc;
> unsigned int i;
> @@ -381,12 +375,16 @@ int tegra_mipi_calibrate(struct tegra_mipi_device *device)
> value |= MIPI_CAL_CTRL_START;
> tegra_mipi_writel(device->mipi, value, MIPI_CAL_CTRL);
>
> - mutex_unlock(&device->mipi->lock);
> - clk_disable(device->mipi->clk);
> + /*
> + * Wait for min 72uS to let calibration logic finish calibration
> + * sequence codes before waiting for pads idle state to apply the
> + * results.
> + */
> + usleep_range(75, 80);

Could you please explain why the ACTIVE bit can't be polled instead of
using the fixed delay? Doesn't ACTIVE bit represents the state of the
busy FSM?