Re: [EXTERNAL] Re: wlcore getting stuck on hikey after the runtime PM autosuspend support change

[Ricardo Salveti <rsalveti@rsalveti.net>]

Hi,

On Thu, Dec 13, 2018 at 12:45 PM Tony Lindgren <tony@atomide.com> wrote:
> * Ricardo Salveti <rsalveti@rsalveti.net> [181213 13:53]:
> > I tried just increasing WL1271_PRE_POWER_ON_SLEEP from 20ms to 50ms
> > (which gets used before calling wl12xx_sdio_power_on), and that was
> > already enough to fix my issues on both hikey and beaglebone black
> > wireless.
>
> OK good to hear that helps :)
>
> > Should we define another pre power on sleep specifically for the sdio
> > case (and use directly in wl12xx_sdio_power_on)?
>
> I'd probably prefer to just increase WL1271_PRE_POWER_ON_SLEEP,
> chances are the same delay is needed in all cases.

Investigating this issue a bit more, I noticed that the hang happens
when PM decides to not suspend the device when doing an if down/up
cycle.

Basically since commit 60f36637bbbd ("wlcore: sdio: allow pm to handle
sdio power") PM is now handling the sdio power off/on process, and if
wl12xx_sdio_power_on gets called right after wl12xx_sdio_power_off (if
down/up), the device will not go to the required power off/on sequence
(since PM will abort the suspend process), and the firmware loading
process will fail. I would guess the problem only happens with
autosuspend because of the extra delay it causes (pm_runtime_put
always returns -EBUSY on wl12xx_sdio_power_off with autosuspend).

Is there a way to force the suspend on wl12xx_sdio_power_off, or
should we partially restore the old behavior?

Thanks,
-- 
Ricardo Salveti de Araujo