[PATCH 5.2 293/413] arm64: tegra: Fix Jetson Nano GPU regulator

From: Greg Kroah-Hartman
Date: Wed Jul 24 2019 - 15:37:08 EST


From: Jon Hunter <jonathanh@xxxxxxxxxx>

commit 434e8aedeaec595933811c2af191db9f11d3ce3b upstream.

There are a few issues with the GPU regulator defined for Jetson Nano
which are:

1. The GPU regulator is a PWM based regulator and not a fixed voltage
regulator.
2. The output voltages for the GPU regulator are not correct.
3. The regulator enable ramp delay is too short for the regulator and
needs to be increased. 2ms should be sufficient.
4. This is the same regulator used on Jetson TX1 and so make the ramp
delay and settling time the same as Jetson TX1.

Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Jon Hunter <jonathanh@xxxxxxxxxx>
Fixes: 6772cd0eacc8 ("arm64: tegra: Add NVIDIA Jetson Nano Developer Kit support")
Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/arm64/boot/dts/nvidia/tegra210-p3450-0000.dts | 17 ++++++++---------
1 file changed, 8 insertions(+), 9 deletions(-)

--- a/arch/arm64/boot/dts/nvidia/tegra210-p3450-0000.dts
+++ b/arch/arm64/boot/dts/nvidia/tegra210-p3450-0000.dts
@@ -633,17 +633,16 @@
};

vdd_gpu: regulator@6 {
- compatible = "regulator-fixed";
+ compatible = "pwm-regulator";
reg = <6>;
-
+ pwms = <&pwm 1 4880>;
regulator-name = "VDD_GPU";
- regulator-min-microvolt = <5000000>;
- regulator-max-microvolt = <5000000>;
- regulator-enable-ramp-delay = <250>;
-
- gpio = <&pmic 6 GPIO_ACTIVE_HIGH>;
- enable-active-high;
-
+ regulator-min-microvolt = <710000>;
+ regulator-max-microvolt = <1320000>;
+ regulator-ramp-delay = <80>;
+ regulator-enable-ramp-delay = <2000>;
+ regulator-settling-time-us = <160>;
+ enable-gpios = <&pmic 6 GPIO_ACTIVE_HIGH>;
vin-supply = <&vdd_5v0_sys>;
};
};