[PATCH 0/2] ARM: dts: Use MMC pwrseq instead regulators for IGEP WiFi init

Tony Lindgren tony at atomide.com
Thu Dec 3 11:27:19 PST 2015

* Javier Martinez Canillas <javier at osg.samsung.com> [151203 10:29]:
> Hello Tony,
> On 12/03/2015 03:16 PM, Tony Lindgren wrote:
> > * Javier Martinez Canillas <javier at osg.samsung.com> [151203 10:03]:
> >> Hello,
> >>
> >> This series converts the IGEPv2 (IGEP0020) and IGEP COM Module (IGEP0030)
> >> Device Tree to use the MMC power sequence provider to initialize the SDIO
> >> WiFi chip instead of using fake fixed regulators to just toggle the Reset
> >> and Power pins in the chip.
> >>
> >> The patches were tested on an DM3730 IGEPv2 board but the IGEP COM Module
> >> is the same with regard to the SDIO WiFi so it should be safe to land too.
> >>
> >> The IGEPv2 Rev.F and the IGEP COM Module Rev.G DTS were not converted due
> >> using a different WiFi chip (wlcore instead of libertas) than the one in
> >> the board I've access to test so I preferred to leave those untouched.
> > 
> > Do you have some solution for the start-up latency issue?
> >
> No, I don't and that's one of the reasons why I didn't want to touch the
> DTS that have the wlcore chip.
> The omap3-igep0020-rev-f.dts and omap3-igep0030-rev-g.dts don't have a
> startup-delay-us property in the regulator for the WLAN_EN pin as is
> the case for the IGEPv5 DTS but I don't know if those DTS are just wrong.


> The DTS for the igep0020 and igep0030 that have the libertas chip,
> did have a startup-delay-us for the WIFI_PDN but using the GPIOs
> for RESET_N_W and WIFI_PDN in the mmc-pwrseq-simple reset-gpios is
> enough to make the SDIO chip reset, be enumerated and WiFi to work
> correctly so I don't know if that is really needed or is just a bad
> description in the DTS.

Hmm OK.

> Since is working for the boards with the libertas chip, I preferred
> to remove the DTS hack but left the boards with wlcore chip since
> you said the startup-delay-us is needed there (but probably we should
> add to the regulators in the boards that don't have it then).




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