Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Subject: Re: [PATCH v4] mmc: mxs-mmc: Introduce regulator support
To:     Robin van der Gracht <robin@protonic.nl>,
        Ulf Hansson <ulf.hansson@linaro.org>
CC:     Martin Kepplinger <martink@posteo.de>,
        "linux-mmc@vger.kernel.org" <linux-mmc@vger.kernel.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        Shawn Guo <shawnguo@kernel.org>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        dl-linux-imx <linux-imx@nxp.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
References: <20190128144119.10092-1-martink@posteo.de>
 <CAPDyKFo7949rcxEX5U2QUS0c2xhC_z+JGeOiF2HC6+QukVpEaQ@mail.gmail.com>
 <20190131092006.363d1dd4@erd987>
 <CAPDyKFr=kcoGK0C2A8JH-nhfgUgoRVa-E=6KPRjFO51QQxjJLA@mail.gmail.com>
 <20190131140930.05c5b6a5@erd987>
From:   Martin Kepplinger <martin.kepplinger@ginzinger.com>
Message-ID: <e79cae34-7dfc-ba93-c79b-4d4abff3afbd@ginzinger.com>
Date:   Thu, 31 Jan 2019 14:15:32 +0100
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101
 Thunderbird/60.4.0
In-Reply-To: <20190131140930.05c5b6a5@erd987>
MIME-Version: 1.0
Content-Type: multipart/signed; protocol="application/x-pkcs7-signature"; micalg="sha-256"; boundary="----FF5873BDBA9B11459ED634B3E5BFCAC7"
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

This is an S/MIME signed message

------FF5873BDBA9B11459ED634B3E5BFCAC7
MIME-Version: 1.0
Content-Type: text/plain; charset="utf-8"; format=flowed
Content-Language: en-US
Content-Transfer-Encoding: 7bit

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:

...

>>>>
>>>> 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

------FF5873BDBA9B11459ED634B3E5BFCAC7
Content-Type: application/x-pkcs7-signature; name="smime.p7s"
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename="smime.p7s"
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------FF5873BDBA9B11459ED634B3E5BFCAC7--