On 4/26/22 16:23, Diogo Ivo wrote:
> Commit 4782c0a5dd88e3797426e08c5c437e95a3156631 ("clk: tegra: Don't
> deassert reset on enabling clocks") removed deassertion of reset lines
> when enabling peripheral clocks. This breaks the initialization of the
> DFLL driver which relied on this behaviour.
>
> Fix this problem by adding explicit deassert/assert requests to the
> driver and the corresponding reset to the DT. Tested on Google Pixel C.
>
Add these tags to the commit message:
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 4782c0a5dd88 ("clk: tegra: Don't deassert reset on enabling clocks")
> Signed-off-by: Diogo Ivo <diogo.ivo@xxxxxxxxxxxxxxxxxx>
> ---
> arch/arm64/boot/dts/nvidia/tegra210.dtsi | 5 +++--
> drivers/clk/tegra/clk-dfll.c | 12 ++++++++++++
> 2 files changed, 15 insertions(+), 2 deletions(-)
...
> @@ -1951,6 +1956,12 @@ int tegra_dfll_register(struct platform_device *pdev,
>
> td->soc = soc;
>
> + td->dfll_rst = devm_reset_control_get(td->dev, "dfll");
This will break devices that aren't affected by the problem of Pixel C.
Use devm_reset_control_get_optional().
