[PATCH v2] coresight: tmc: Don't enable TMC when it's not ready.

[Yabin Cui]

Hi,

> > There is a similar unprepare function in ETR - this should have similar updates.

Thanks for reminding me! I will update the patch to fix it.

> > The tmc_flush_and_stop() function also calls tmc_wait_for_tmcready().
>
> I think this already an error message there, when it fails to complete
> the flush.I thought of adding a WARN_ON, but thought it is not worth much.

I can see error messages when tmc flush timeouts or tmcready timeouts.
I don't know how the callers (read_buffer and disable) can handle this error.
I think the perf event call chain doesn't accept failures when
disabling coresight
devices. So I feel reporting the error is the best effort we can do.

Thanks,
Yabin