Re: [RFC PATCH v2 14/18] gpu: host1x: mipi: Split tegra_mipi_calibrate and tegra_mipi_wait

From: Dmitry Osipenko
Date: Wed Jun 17 2020 - 20:35:28 EST


17.06.2020 04:41, Sowjanya Komatineni ÐÐÑÐÑ:
...
> -static int tegra_mipi_wait(struct tegra_mipi *mipi)
> +int tegra_mipi_wait(struct tegra_mipi_device *device)
> {
> + struct tegra_mipi *mipi = device->mipi;
> unsigned long timeout = jiffies + msecs_to_jiffies(250);
> u32 value;
> + int err;
> +
> + err = clk_enable(device->mipi->clk);
> + if (err < 0)
> + return err;
> +
> + mutex_lock(&device->mipi->lock);

The timeout variable should be assigned *after* taking the lock.

It will be better if you could use the read_poll_timeout() or
readl_relaxed_poll_timeout() here.

> while (time_before(jiffies, timeout)) {
> value = tegra_mipi_readl(mipi, MIPI_CAL_STATUS);
> if ((value & MIPI_CAL_STATUS_ACTIVE) == 0 &&
> (value & MIPI_CAL_STATUS_DONE) != 0)
> - return 0;
> + goto done;
>
> usleep_range(10, 50);
> }
>
> - return -ETIMEDOUT;
> + err = -ETIMEDOUT;
> +done:
> + mutex_unlock(&device->mipi->lock);
> + clk_disable(device->mipi->clk);
> + return err;
> }
> +EXPORT_SYMBOL(tegra_mipi_wait);