On 18/11/2019 09.04, Joakim Zhang wrote:
Hi Joakim and Marc
We have quite a few devices in the field where flexcan is stuck in Stop-Mode.
We do not have the possibility to cold reboot them, and hot reboot
will not get flexcan out of stop-mode.
So flexcan comes up with:
[ 279.444077] flexcan: probe of 2090000.flexcan failed with error
-110 [ 279.501405] flexcan: probe of 2094000.flexcan failed with
error -110
They are on, de3578c198c6 ("can: flexcan: add self wakeup support")
Would it be a solution to add a check in the probe function to pull
it out of stop-mode?
Hi Sean,
Soft reset cannot be applied when clocks are shut down in a low power mode.
The module should be first removed from low power mode, and then soft reset
can be applied.
And exit from stop mode happens when the Stop mode request is removed,
or when activity is detected on the CAN bus and the Self Wake Up mechanism is
enabled.
So from my point of view, we can add a check in the probe function to
pull it out of stop mode, since controller actually could be stuck in stop mode
if suspend/resume failed and users just want a warm reset for the system.
Exactly what I thought could be done :)
Could you please tell me how can I generate a warm reset? AFAIK, both
"reboot" command put into prompt and RST KEY in our EVK board all play a role
of cold reset.
Warm reset is just `reboot` :-) Cold is poweroff...
I add the code flexcan_enter_stop_mode(priv) at the end of the probe function, 'reboot' the system directly after system active.
However, I do not meet the probe error, it can probe successfully. Do you know the reason?
You will have to get it in the deadlock situation first :)
This can be achieved by using de3578c198c6 and sending can messages to
both can interfaces while calling suspend.
/Sean
