linux-kernel - Re: Question about "regulator: core: Only count load for enabled consumers" in -next

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Message-ID: <CAD=FV=VuPerEgPPiUKk7-Ck9aVz=oR1CAAzg+0wag1WTrTGKxg@mail.gmail.com>
Date:   Sun, 25 Nov 2018 09:20:02 -0800
From:   Doug Anderson <dianders@...omium.org>
To:     masneyb@...tation.org
Cc:     Mark Brown <broonie@...nel.org>,
        Liam Girdwood <lgirdwood@...il.com>,
        LKML <linux-kernel@...r.kernel.org>
Subject: Re: Question about "regulator: core: Only count load for enabled
 consumers" in -next

Hi,

On Sun, Nov 25, 2018 at 1:37 AM Brian Masney <masneyb@...tation.org> wrote:
> I bisected the issue to the following commit:
>
> 5451781dadf8 ("regulator: core: Only count load for enabled consumers")
>
> We have to increase the load for the sdhci in device tree in order for
> the phone to boot properly. This change was made with the commit:
>
> 03864e57770a ("ARM: dts: qcom: msm8974-hammerhead: increase load on l20
> for sdhci")

You have a 200 mA system load on this regulator?  I guess this is a
workaround for drivers that don't set the load properly themselves?

I wonder if there is a bug in my patch where the system load doesn't
take effect if nobody ever calls set_load.  Let's see...  Does the
below fix things for you?  It's totally untested and whitespace
damaged but I wanted to get a response out quick and I'm just walking
out the door.  I'll test more / dig more either tonight or at work
tomorrow:

+++ b/drivers/regulator/core.c
@@ -1344,6 +1344,12 @@ static int set_machine_constraints(struct
regulator_dev *rdev,
                        rdev_err(rdev, "failed to set initial mode: %d\n", ret);
                        return ret;
                }
+       } else if (rdev->constraints->system_load) {
+               /*
+                * We'll only apply the initial system load if an
+                * initial mode wasn't specified.
+                */
+               drms_uA_update(rdev);
        }