Re: [PATCH v8 08/10] gpu: host1x: mipi: Keep MIPI clock enabled till calibration is done

From: Sowjanya Komatineni
Date: Thu Aug 06 2020 - 14:10:13 EST



On 8/6/20 11:01 AM, Dmitry Osipenko wrote:
06.08.2020 20:52, Sowjanya Komatineni пишет:
...
Right mutex_unlock should happen at end of finish_calibration.

With keeping mutex locked in start, we dont have to check for active to
be 0 to issue start as mutex will keep it locked and other pads
calibration can only go thru when current one is done.

So instead of below sequence, its simpler to do this way?

start_calibration()

- mutex_lock

- wait for 72uS after start

finish_calibration()

- keep check for ACTIVE = 0 and DONE = 1
I think only the DONE bits which correspond to the mipi_device->pads
bitmask should be awaited.

As next START can't be triggered when auto cal is ACTIVE, we should keep this in finish.

As we do mutex_unlock only at end of finish, other pads calibrations dont go thru till the one in process is finished.

So in this case ACTIVE applies to current selected pads that are under calibration.


- mutex_unlock()
Perhaps the start_calibration() also needs to be changed to not touch
the MIPI_CAL_CONFIG bits of the unrelated pads?
Driver already takes care of programming corresponding pads config only.

Otherwise sounds good to me.