From: Jon Hunter jonathanh@nvidia.com
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@vger.kernel.org Signed-off-by: Jon Hunter jonathanh@nvidia.com Fixes: 6772cd0eacc8 ("arm64: tegra: Add NVIDIA Jetson Nano Developer Kit support") Signed-off-by: Thierry Reding treding@nvidia.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- 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>; }; };