Messages in this thread | | | Subject | Re: [PATCH v4] mmc: mxs-mmc: Introduce regulator support | From | Martin Kepplinger <> | Date | Thu, 31 Jan 2019 14:15:32 +0100 |
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On 31.01.19 14:09, Robin van der Gracht wrote: > On Thu, 31 Jan 2019 13:17:23 +0100 > Ulf Hansson <ulf.hansson@linaro.org> wrote: > >> On Thu, 31 Jan 2019 at 09:20, Robin van der Gracht <robin@protonic.nl> wrote: >>> >>> On Mon, 28 Jan 2019 22:15:23 +0100 >>> Ulf Hansson <ulf.hansson@linaro.org> wrote:
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>>>> >>>> BTW, you didn't really answer my earlier question about the TI WiFi >>>> chip. Doesn't you need a special clock for WiFi chip as well? How do >>>> you intend to manage that? >>> >>> I used an external 32K oscillator (SLOW_CLK) for my wl1271. Other >>> clocks ware generated on the module. >> >> Right. How do you control that clock? Did you model it as clock via >> the common clock framework? > > No I didn't. The slow clock (sleep clock) was always 'on'. > >> >>> >>> I had to supply a 'vmmc-supply' in your wl1271 devicetree node, >>> which will be used to power on/off the wlan module. The supply should >>> be a (delayed) GPIO controlled 'fixed-regulator' attached to the >>> wlan_en pin on the module. >> >> Right, thanks for explaining. >> >>> >>> 1: Documentation/devicetree/bindings/net/wireless/ti,wlcore.txt >>> >> >> This sounds like a good fit for mmc pwrseq simple. There are already >> similar users for it. >> >> Have a look at: /drivers/mmc/core/pwrseq* >> If the mmc host driver calls mmc_of_parse() during ->probe(), a pwrseq >> instance will be hooked up to it. Once the mmc core tries to power up >> the card it will make use of the attached pwrseq for the mmc host in >> question. >> >> In this way, you can control the clock and GPIO line, in more exact >> ways that is needed by the WiFi chip. > > Ack. Makes more sense than using a regulator (even without specifying > 'clocks'). >
Thanks Ulf! Sounds promising.
>> >> Here is a DT example (look for "mmc-pwrseq-simple"): >> arch/arm/boot/dts/imx6qdl-sr-som-ti.dtsi >> >> This should do the trick for you. On the other hand, I don't mind that >> you still add regulator support to the driver, along the lines of what >> $subject patch does, however it may not be exactly what you need for >> the WiFi case. > > @Martin; What do you think? Will you work this out with Ulf? > Since I can't test this.
I'll test Ulf's suggestion and go that way if I get it to work. Give me a few days though.
Thanks a lot for your help so far Robin,
martin [unhandled content-type:application/x-pkcs7-signature] | |