RE: [PATCH v1] ARM: dts: imx6sl-evk: keep sw4 always on

From: Anson Huang
Date: Sun Jul 01 2018 - 21:19:29 EST




Anson Huang
Best Regards!


> -----Original Message-----
> From: Fabio Estevam [mailto:festevam@xxxxxxxxx]
> Sent: Monday, July 2, 2018 9:17 AM
> To: Anson Huang <anson.huang@xxxxxxx>
> Cc: Shawn Guo <shawnguo@xxxxxxxxxx>; Robin Gong <yibin.gong@xxxxxxx>;
> Mark Rutland <mark.rutland@xxxxxxx>; open list:OPEN FIRMWARE AND
> FLATTENED DEVICE TREE BINDINGS <devicetree@xxxxxxxxxxxxxxx>;
> linux-kernel <linux-kernel@xxxxxxxxxxxxxxx>; Rob Herring
> <robh+dt@xxxxxxxxxx>; dl-linux-imx <linux-imx@xxxxxxx>; Sascha Hauer
> <kernel@xxxxxxxxxxxxxx>; Fabio Estevam <fabio.estevam@xxxxxxx>;
> moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE
> <linux-arm-kernel@xxxxxxxxxxxxxxxxxxx>
> Subject: Re: [PATCH v1] ARM: dts: imx6sl-evk: keep sw4 always on
>
> On Sun, Jul 1, 2018 at 10:09 PM, Anson Huang <anson.huang@xxxxxxx>
> wrote:
>
> > On some new i.MX platforms, PFuze switches are used for supplying
> > GPU/VPU or other non-critical modules only, these switches need to be
> > turned off by runtime PM to avoid very high power leakage, like on
> mScale850D.
>
> Ok, in this case I suggest adding a new property so that the switches can be
> turned off only when the new property is present.
>
> When this new property is absent, then we keep the current behavior and avoid
> dtb breakage.
>
> Since MX8M support is not in place yet, this is not urgent, so I will send a revert
> and then you can re-work the patch so that it does not affect the old dtbs.
>
> Do you agree with such approach?

Sure, I agree for now. As I did NOT want to have any breakage. Thanks.

Anson.