[PATCH 5.15 049/279] cpuidle: tegra: Check whether PMC is ready

Greg Kroah-Hartman
2021-11-24T13:52:06Z

From: Dmitry Osipenko <digetx@gmail.com>

[ Upstream commit bdb1ffdad3b73e4d0538098fc02e2ea87a6b27cd ]

Check whether PMC is ready before proceeding with the cpuidle registration.
This fixes racing with the PMC driver probe order, which results in a
disabled deepest CC6 idling state if cpuidle driver is probed before the
PMC.

Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/cpuidle/cpuidle-tegra.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/cpuidle/cpuidle-tegra.c b/drivers/cpuidle/cpuidle-tegra.c
index 508bd9f237929..9845629aeb6d4 100644
--- a/drivers/cpuidle/cpuidle-tegra.c
+++ b/drivers/cpuidle/cpuidle-tegra.c
@@ -337,6 +337,9 @@ static void tegra_cpuidle_setup_tegra114_c7_state(void)

static int tegra_cpuidle_probe(struct platform_device *pdev)
{
+ if (tegra_pmc_get_suspend_mode() == TEGRA_SUSPEND_NOT_READY)
+ return -EPROBE_DEFER;
+
/* LP2 could be disabled in device-tree */
if (tegra_pmc_get_suspend_mode() < TEGRA_SUSPEND_LP2)
tegra_cpuidle_disable_state(TEGRA_CC6);
--
2.33.0