22.3.3 Programming Interface
The thermal driver can be accessed through /sys/class/thermal/thermal_zone/.
22.3.4 Interrupt Requirements
The thermal driver uses irq #81. Set the alarm value to critical trip point. When the
temperature exceeds the critical trip point, the interrupt handler will reset the system to
protect SoC.
22.4 Unit Test
Modify the trip point's temperature through /sys/class/thermal/thermal_zone0/
trip_point_x_temp. Here, 'x' can be 0, 1 and 2, indicating critical, hot and active trip
point, and the value of trip points should be critical > hot > active. Then run some
program to make SoC in heavy loading. When the SoC temperature reaches the trip
points, the thermal driver will take action to do some protections according to each trip
point's mechanism. Restore the trip point's temperature. When SoC temperature drops to
below active trip point, thermal driver will remove all the protections.
Chapter 22 Thermal Driver
i.MX 6Solo/6DualLite Linux Reference Manual, Rev. L3.0.35_4.1.0, 09/2013
Freescale Semiconductor, Inc.
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