24.07.2020 02:51, Sowjanya Komatineni пишет:
> VI I2C is on host1x bus and is part of VE power domain.
>
> During suspend/resume VE power domain goes through power off/on.
>
> So, controller reset followed by i2c re-initialization is required
> after the domain power up.
>
> This patch fixes it.
>
> Signed-off-by: Sowjanya Komatineni <skomatineni@xxxxxxxxxx>
> ---
> drivers/i2c/busses/i2c-tegra.c | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)
>
> diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
> index 7b93c45..1bf3666 100644
> --- a/drivers/i2c/busses/i2c-tegra.c
> +++ b/drivers/i2c/busses/i2c-tegra.c
> @@ -293,6 +293,8 @@ struct tegra_i2c_dev {
> bool is_curr_atomic_xfer;
> };
>
> +static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev, bool clk_reinit);
> +
> static void dvc_writel(struct tegra_i2c_dev *i2c_dev, u32 val,
> unsigned long reg)
> {
> @@ -675,8 +677,22 @@ static int __maybe_unused tegra_i2c_runtime_resume(struct device *dev)
> goto disable_slow_clk;
> }
>
> + /*
> + * VI I2C device is attached to VE power domain which goes through
> + * power ON/OFF during PM runtime resume/suspend. So, controller
> + * should go through reset and need to re-initialize after power
> + * domain ON.
> + */
> + if (i2c_dev->is_vi) {
> + ret = tegra_i2c_init(i2c_dev, true);
> + if (ret)
> + goto disable_div_clk;
> + }
> +
> return 0;
>
> +disable_div_clk:
> + clk_disable(i2c_dev->div_clk);
> disable_slow_clk:
> clk_disable(i2c_dev->slow_clk);
> disable_fast_clk:
>
This look okay, but isn't RPM usage a bit too expensive for VI? Maybe
RPM autodelay needs to be set for the I2C driver?
Reviewed-by: Dmitry Osipenko <digetx@xxxxxxxxx>
