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: 783807436f36 ("soc/tegra: regulators: Add regulators coupler for Tegra30")
Cc: stable@xxxxxxxxxxxxxxx
Reported-by: Peter Geis <pgwipeout@xxxxxxxxx>
Tested-by: Peter Geis <pgwipeout@xxxxxxxxx> # Ouya T30
Tested-by: Matt Merhar <mattmerhar@xxxxxxxxxxxxxx> # Ouya T30
Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
---
drivers/soc/tegra/regulators-tegra30.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/soc/tegra/regulators-tegra30.c b/drivers/soc/tegra/regulators-tegra30.c
index 7f21f31de09d..0e776b20f625 100644
--- a/drivers/soc/tegra/regulators-tegra30.c
+++ b/drivers/soc/tegra/regulators-tegra30.c
@@ -178,7 +178,7 @@ static int tegra30_voltage_update(struct tegra_regulator_coupler *tegra,
* survive the voltage drop if it's running on a higher frequency.
*/
if (!cpu_min_uV_consumers)
- cpu_min_uV = cpu_uV;
+ cpu_min_uV = max(cpu_uV, cpu_min_uV);
/*
* Bootloader shall set up voltages correctly, but if it
--
2.29.2
