TX2 PWM status

Autonomous Machines Jetson & Embedded Systems Jetson TX2
1

Hi ,
Is is possible that when system in suspend mode and pwm duty keeps?

TX2 has 8 set pwms,

display1 backlight “Active in Low-power = NO”
display2 backlight “Active in Low-power = NO”
Haptics “Active in Low-power = NO”
FAN Control “Active in Low-power = YES”
PEX_L2_CLKREQ_N “Active in Low-power = NO”
GP_PWM6 “Active in Low-power = NO”
GP_PWM7 “Active in Low-power = NO”
UART5_RX “Active in Low-power = NO”

Regards

2

yi-chia.lan,

Where did you find this line? Is this from nvidia?
“FAN Control “Active in Low-power = YES””

3

Hi yi-chia.lan,

Please refer to this thread. If you are still using fan, you could try to change “active_pwm” to all 255 and see if fan is still spinning after suspension mode.

[url]https://devtalk.nvidia.com/default/topic/1030380/jetson-tx2/can-fan-pwm-be-used-for-pulse-counting-/post/5241805/#5241805[/url]

4

Hi WayneWWW,

Would you please explain what is “Active in Low-Power State” ?? Is is same as suspend mode ??

I got this information from Parker_TRM_DP07821001p.pdf (TRM) chapter 40.(40.1 Use Cases)
I tried to mask pwm_fan.c suspend/resume but and pwm stop output duty cycle while suspend.

What I need is to keep PWM duty when system suspend.

static struct platform_driver pwm_fan_driver = {
	.driver = {
		.name	= "pwm_fan_driver",
		.owner = THIS_MODULE,
		.of_match_table = of_pwm_fan_match,
	},
	.probe = pwm_fan_probe,
	.remove = pwm_fan_remove,
#if CONFIG_PM
	//.suspend = pwm_fan_suspend,
	//.resume = pwm_fan_resume,
#endif
};