您好，我从kernel设备树配置GPIO 的pinmux没有生效。如下是我的配置代码：我想将PDD7配置成GPIO
//padctl_aon
pinmux@c7a2000 {
pinctrl-names = "default";
pinctrl-0 = <&pinmux_default_c7a2000>;
pinmux_default_c7a2000: common_c7a2000 {
tca9546_0_rst_pdd7 {
nvidia,pins = "soc_gpio25_pdd7";
nvidia,function = "rsvd0";
nvidia,pull = <TEGRA_PIN_PULL_UP>;
nvidia,tristate = <TEGRA_PIN_DISABLE>;
nvidia,enable-input = <TEGRA_PIN_DISABLE>;
nvidia,e-io-od = <TEGRA_PIN_DISABLE>;
nvidia,e-lpbk = <TEGRA_PIN_DISABLE>;
};
tca9546_1_rst_pdd5 {
nvidia,pins = "soc_gpio23_pdd5";
nvidia,function = "rsvd1";
nvidia,pull = <TEGRA_PIN_PULL_UP>;
nvidia,tristate = <TEGRA_PIN_DISABLE>;
nvidia,enable-input = <TEGRA_PIN_DISABLE>;
nvidia,e-io-od = <TEGRA_PIN_DISABLE>;
nvidia,e-lpbk = <TEGRA_PIN_DISABLE>;
};
};
};
查看pinctrl-maps已经应用了pinmux
root@tegra:/home/robot# cat /sys/kernel/debug/pinctrl/pinctrl-maps
Pinctrl maps:
device c7a2000.pinmux
state default
type MUX_GROUP (2)
controlling device c7a2000.pinmux
group soc_gpio23_pdd5
function rsvd1
device c7a2000.pinmux
state default
type CONFIGS_GROUP (4)
controlling device c7a2000.pinmux
group soc_gpio23_pdd5
config pull=2
config tristate=0
config enable-input=0
device c7a2000.pinmux
state default
type MUX_GROUP (2)
controlling device c7a2000.pinmux
group soc_gpio25_pdd7
function rsvd0
device c7a2000.pinmux
state default
type CONFIGS_GROUP (4)
controlling device c7a2000.pinmux
group soc_gpio25_pdd7
config pull=2
config tristate=0
config enable-input=0
但是无论我的配置是什么，linux操作GPIO的电平都没有变化.
Hi chutianwei,
They are the pinmux register configuration rather than the pin state control.
$ sudo busybox devem 0x0c7a3078
Could you use pinmux spreadsheet to configure it as following?
在MB1阶段将PU7复用成PWM5，配置如下
系统启动之后，驱动PWM5 enable，但是pu7并没有任何波形输出，同时cat pinmux发现pu7的io-reset=1
cat /sys/kernel/debug/pinctrl/810c281000.pinmux/pinconf-groups
94 (soc_gpio177_pu7):
pull=0
tristate=0
enable-input=0
open-drain=1
io-reset=1
rcv-sel=1
io-hv=1
schmitt=0
pull-down-strength=8
pull-up-strength=8
drive-type=1
gpio-mode=1
function=gp_pwm5
我是不是需要先解除io-reset=1状态，我应该如何解除？
Could you share the result of the following command on your board?
//SOC_GPIO177
$ sudo busybox devmem 0x810c2870a0
chutianwei:
驱动PWM5 enable
How do you enable PWM5? Could you share the steps?
robot@tegra:~$ sudo busybox devmem 0x810c2870a0
[sudo] password for robot:
0x00203409
enable PWM5流程如下：
overlay kernel设备树
//pwm5
pwm@810c600000 {
status = "okay";
};
通过debug文件系统查看PWM对应的index,确定PWM5对应的pwmchip index为3
root@tegra:/home/robot# cat /sys/kernel/debug/pwm
0: platform/c6a0000.pwm, 1 PWM device
pwm-0 (pwm-fan ): requested enabled period: 40000 ns duty: 12079 ns polarity: normal usage_power
1: platform/810c5e0000.pwm, 1 PWM device
pwm-0 ((null) ): period: 0 ns duty: 0 ns polarity: normal
2: platform/810c5f0000.pwm, 1 PWM device
pwm-0 ((null) ): period: 0 ns duty: 0 ns polarity: normal
3: platform/810c600000.pwm, 1 PWM device
pwm-0 ((null) ): period: 0 ns duty: 0 ns polarity: normal
4: platform/810c610000.pwm, 1 PWM device
pwm-0 ((null) ): period: 0 ns duty: 0 ns polarity: normal
5: platform/810c620000.pwm, 1 PWM device
pwm-0 ((null) ): period: 0 ns duty: 0 ns polarity: normal
6: platform/810c5c0000.tachometer, 1 PWM device
pwm-0 ((null) ): period: 0 ns duty: 0 ns polarity: normal
通过sys文件系统配置使能PWM5
echo 0 > /sys/class/pwm/pwmchip3/export
echo 33333333 > /sys/class/pwm/pwmchip3/pwm0/period
echo 3333333 > /sys/class/pwm/pwmchip3/pwm0/duty_cycle
echo 1 > /sys/class/pwm/pwmchip3/pwm0/enable
现象：在没有enable PWM5之前，引脚为高电平；enable PWM5之后，引脚持续低电平，没有PWM波形
最新发现，echo 40000 > /sys/class/pwm/pwmchip3/pwm0/period
echo 10000 > /sys/class/pwm/pwmchip3/pwm0/duty_cycle
时PWM信号输出正常，如果period设置大于10ms，之后PWM持续输出低电平，我的PWM是给相机使用，所以配置成30HZ时，PWM工作异常，这个功能在AGX orin上是能正常工作的。请帮忙定位原因
Have you tried to update the parent clock and compare the clock frequency on both platform?
chutianwei:
发现分频值大于0xFF之后，PWM就没有波形了
Yes, it is expected as the valid value should be between 0x0 and 0xFF.
system
October 22, 2025, 5:56am
11
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