From mboxrd@z Thu Jan  1 00:00:00 1970
From: Fabio Estevam <festevam@gmail.com>
Subject: Re: [PATCH v1] ARM: dts: imx6sl-evk: keep sw4 always on
Date: Sun, 1 Jul 2018 20:32:49 -0300
Message-ID: <CAOMZO5BjOEGWv2dC-bp0BYHq+PhLssEKic+o7ock8_1Dobd=sQ@mail.gmail.com>
References: <1529930051-14122-1-git-send-email-yibin.gong@nxp.com> <20180701093402.GN4348@dragon>
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To: Shawn Guo <shawnguo@kernel.org>, Yongcai Huang <anson.huang@nxp.com>
Cc: Robin Gong <yibin.gong@nxp.com>, Mark Rutland <mark.rutland@arm.com>, "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" <devicetree@vger.kernel.org>, linux-kernel <linux-kernel@vger.kernel.org>, Rob Herring <robh+dt@kernel.org>, NXP Linux Team <linux-imx@nxp.com>, Sascha Hauer <kernel@pengutronix.de>, Fabio Estevam <fabio.estevam@nxp.com>, "moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE" <linux-arm-kernel@lists.infradead.org>
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On Sun, Jul 1, 2018 at 6:34 AM, Shawn Guo <shawnguo@kernel.org> wrote:
> On Mon, Jun 25, 2018 at 08:34:11PM +0800, Robin Gong wrote:
>> SW4 is one power rail for LPDDR2 on i.mx6sl-evk, so it should
>> be kept always on. But it's disabled after switch disabled
>> interface implemented in pfuze driver
>> 'commit 5fe156f1cab4
>> ("regulator: pfuze100: add enable/disable for switch")'.Thus,
>> it breaks kernel bootup. Add 'regulator-always-on' for SW4.
>>
>> Signed-off-by: Robin Gong <yibin.gong@nxp.com>
>
> Does that mean boards with existing DTB installed will stop working with
> new kernel?  That's bad, and the kernel commit should probably be
> reverted.

Yes, this is a good point.

Anson,

Should 5fe156f1cab4 ("regulator: pfuze100: add enable/disable for
switch") be reverted to avoid such breakage?