Re: [PATCH] wlcore: Fix bringing up wlan0 again if powered down briefly

[Tony Lindgren <tony-4v6yS6AI5VpBDgjK7y7TUQ@public.gmane.org>]

Hi,

* Ulf Hansson <ulf.hansson-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> [181218 12:34]:
> Instead, it looks like what you need, is a way to keep track of
> whether the SDIO card, became power cycled or if it stayed powered on,
> when "ifconfig wlan0 up" is done. In case of a power cycle, you need
> to re-program the firmware, right?

Yeah mostly. But we also need to ensure things do get powered down
properly after ifconfig wlan0 down :) IMO after ifconfig wlan0 down
returns, there should be no waiting needed.

> Would it be possible to re-program the firmware, even if the SDIO card
> stayed powered-on?

That might help for some cases, but the problem of how to ensure the
card is powered down after ifconfig wlan0 down returns still exists.

> In regards to delays needed due to a capacitance. If that really is
> the case, that shall be the managed by the mmc core, as it's there the
> power cycle sequence is being done. As a matter of fact, you should be
> able to use drivers/mmc/core/pwrseq_simple.c and extend
> "power-off-delay-us" in the DTB for Hikey if that is needed.

Hmm I do have a mostly done wlcore pwrseq driver here somewhere that
I have not had a chance to finish again. But that's not going to work
for a fix and needs updating of the related dts files too.

Regards,

Tony