[PATCH 5.10 050/299] cpuidle: tegra: Fix C7 idling state on Tegra114

[Greg Kroah-Hartman]

From: Dmitry Osipenko <digetx@xxxxxxxxx>

commit 32c8c34d8132b5fe8497c2538597445a0d65c29d upstream.

Trusted Foundation firmware doesn't implement the do_idle call and in
this case suspending should fall back to the common suspend path. In order
to fix this issue we will unconditionally set the NOFLUSH_L2 mode via
firmware call, which is a NO-OP on Tegra30/124, and then proceed to the
C7 idling, like it was done by the older Tegra114 cpuidle driver.

Fixes: 14e086baca50 ("cpuidle: tegra: Squash Tegra114 driver into the common driver")
Cc: stable@xxxxxxxxxxxxxxx # 5.7+
Reported-by: Anton Bambura <jenneron@xxxxxxxxxxxxxx> # TF701 T114
Tested-by: Anton Bambura <jenneron@xxxxxxxxxxxxxx> # TF701 T114
Tested-by: Matt Merhar <mattmerhar@xxxxxxxxxxxxxx> # Ouya T30
Tested-by: Peter Geis <pgwipeout@xxxxxxxxx> # Ouya T30
Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
Reviewed-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210302095405.28453-1-digetx@xxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/cpuidle/cpuidle-tegra.c |   12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

--- a/drivers/cpuidle/cpuidle-tegra.c
+++ b/drivers/cpuidle/cpuidle-tegra.c
@@ -135,13 +135,13 @@ static int tegra_cpuidle_c7_enter(void)
 {
 	int err;
 
-	if (tegra_cpuidle_using_firmware()) {
-		err = call_firmware_op(prepare_idle, TF_PM_MODE_LP2_NOFLUSH_L2);
-		if (err)
-			return err;
+	err = call_firmware_op(prepare_idle, TF_PM_MODE_LP2_NOFLUSH_L2);
+	if (err && err != -ENOSYS)
+		return err;
 
-		return call_firmware_op(do_idle, 0);
-	}
+	err = call_firmware_op(do_idle, 0);
+	if (err != -ENOSYS)
+		return err;
 
 	return cpu_suspend(0, tegra30_pm_secondary_cpu_suspend);
 }