Commit Graph

3 Commits

Author SHA1 Message Date
Dmitry Osipenko ef85bb582c soc/tegra: regulators: Fix locking up when voltage-spread is out of range
Fix voltage coupler lockup which happens when voltage-spread is out
of range due to a bug in the code. The max-spread requirement shall be
accounted when CPU regulator doesn't have consumers. This problem is
observed on Tegra30 Ouya game console once system-wide DVFS is enabled
in a device-tree.

Fixes: 783807436f ("soc/tegra: regulators: Add regulators coupler for Tegra30")
Cc: stable@vger.kernel.org
Reported-by: Peter Geis <pgwipeout@gmail.com>
Tested-by: Peter Geis <pgwipeout@gmail.com> # Ouya T30
Tested-by: Matt Merhar <mattmerhar@protonmail.com> # Ouya T30
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2021-03-26 13:10:25 +01:00
Dmitry Osipenko 45f019a684 soc/tegra: regulators: Do nothing if voltage is unchanged
There is no need to re-apply the same voltage. This change is just a minor
cleanup.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2020-01-10 15:42:58 +01:00
Dmitry Osipenko 783807436f soc/tegra: regulators: Add regulators coupler for Tegra30
Add regulators coupler for Tegra30 SoCs that performs voltage balancing
of a coupled regulators and thus provides voltage scaling functionality.

There are 2 coupled regulators on all Tegra30 SoCs: CORE and CPU. The
coupled regulator voltages shall be in a range of 300mV from each other
and CORE voltage shall be higher than the CPU by N mV, where N depends
on the CPU voltage.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-By: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2019-10-29 14:02:59 +01:00