Re: [PATCH] dd: Invoke one probe retry cycle after every initcall level

From: Rafael J. Wysocki
Date: Tue Jul 24 2018 - 04:24:56 EST

On Mon, Jul 23, 2018 at 10:22 PM, <rishabhb@xxxxxxxxxxxxxx> wrote:
> On 2018-07-23 04:17, Rafael J. Wysocki wrote:
>> On Thu, Jul 19, 2018 at 11:24 PM, Rishabh Bhatnagar
>> <rishabhb@xxxxxxxxxxxxxx> wrote:
>>> Drivers that are registered at an initcall level may have to
>>> wait until late_init before the probe deferral mechanism can
>>> retry their probe functions. It is possible that their
>>> dependencies were resolved much earlier, in some cases even
>>> before the next initcall level. Invoke one probe retry cycle
>>> at every _sync initcall level, allowing these drivers to be
>>> probed earlier.
>> Can you please say something about the actual use case this is
>> expected to address?
> We have a display driver that depends 3 other devices to be
> probed so that it can bring-up the display. Because of dependencies
> not being met the deferral mechanism defers the probes for a later time,
> even though the dependencies might be met earlier. With this change
> display can be brought up much earlier.


What runlevel brings up the display after the change?