How to wake up i.MX6Q from suspend by can frames while TJA1044 is in standby mode

[masonyen]

i.MX6Q system enters suspend state by "echo mem > /sys/power/state". While TAJ1043 is in normal mode, i.MX6Q system can be waked up by can frames. But when TJA1043 is in standby mode, i.MX6Q system cannot be waked up by can frames. The TTJA1044 RXD did switch low after sending CAN frames.

How to wake up i.MX6Q from suspend by can frames while TJA1044 is also in standby mode

[masonyen]

Hi Rita,

We noticed that i.MX6 system cannot be woke up from suspend if TJA1044  CAN device is down(ifconfig can1 down). Is this a bug, or it works as designed?

If TJA1044  CAN device is up(ip link set can0 up type can bitrate 500000), the i.MX6 system can be woke up from can frames.

Cheers,

Mason

[Rita_Wang]

Hi Mason,

Update from our expert team:

Yes, it is obvious that iMX6 system can not be woken up from suspend if can interface is down (ifconfig can0 down) because it is not going to receive any data/activity on CAN interface.

If your CAN interface is UP i.e. ifconfig can0 up and iMX6 system is in suspend then it will be able to wake up through can frames.

Hope this can do help for you.

Have a nice day

Rita

[Rita_Wang]

Hi，

Firstly, you need to wake up the TTJA1044 then only i.MX6Q system will get wake up from suspend through TTJA1044 can frames.

You can refer Section 7.2 Remote Wake up of attached TTJA1044 datasheet to wake up the TTJA1044 from stand by mode.

Have a nice day

Rita