Thanks for your information.
The trick is very simple. Just add in the /boot/boot/config.txt
dtparam=i2c_arm=on
# i2cdetect -l
i2c-1 i2c bcm2835 (i2c@7e804000) I2C adapter
i2c-20 i2c Broadcom STB : I2C adapter
i2c-21 i2c Broadcom STB : I2C adapter
or add
dtoverlay=pwm,pin=18,func=2
#ls /sys/class/pwm/pwmchip0
device export npwm power subsystem uevent unexport
# lsmod|grep pwm
pwm_bcm2835 16384 0