Patch "regulator: resolve supply after creating regulator" has been added to the 5.9-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    regulator: resolve supply after creating regulator

to the 5.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     regulator-resolve-supply-after-creating-regulator.patch
and it can be found in the queue-5.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit cdb704ed70a7390b105f3f430d1f6ad20391a718
Author: MichaÅ? MirosÅ?aw <mirq-linux@xxxxxxxxxxxx>
Date:   Sat Sep 26 23:32:41 2020 +0200

    regulator: resolve supply after creating regulator
    
    [ Upstream commit aea6cb99703e17019e025aa71643b4d3e0a24413 ]
    
    When creating a new regulator its supply cannot create the sysfs link
    because the device is not yet published. Remove early supply resolving
    since it will be done later anyway. This makes the following error
    disappear and the symlinks get created instead.
    
      DCDC_REG1: supplied by VSYS
      VSYS: could not add device link regulator.3 err -2
    
    Note: It doesn't fix the problem for bypassed regulators, though.
    
    Fixes: 45389c47526d ("regulator: core: Add early supply resolution for regulators")
    Signed-off-by: MichaÅ? MirosÅ?aw <mirq-linux@xxxxxxxxxxxx>
    Link: https://lore.kernel.org/r/ba09e0a8617ffeeb25cb4affffe6f3149319cef8.1601155770.git.mirq-linux@xxxxxxxxxxxx
    Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 7ff507ec875a8..4859cf84c0b2f 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -5256,15 +5256,20 @@ regulator_register(const struct regulator_desc *regulator_desc,
 	else if (regulator_desc->supply_name)
 		rdev->supply_name = regulator_desc->supply_name;
 
-	/*
-	 * Attempt to resolve the regulator supply, if specified,
-	 * but don't return an error if we fail because we will try
-	 * to resolve it again later as more regulators are added.
-	 */
-	if (regulator_resolve_supply(rdev))
-		rdev_dbg(rdev, "unable to resolve supply\n");
-
 	ret = set_machine_constraints(rdev, constraints);
+	if (ret == -EPROBE_DEFER) {
+		/* Regulator might be in bypass mode and so needs its supply
+		 * to set the constraints */
+		/* FIXME: this currently triggers a chicken-and-egg problem
+		 * when creating -SUPPLY symlink in sysfs to a regulator
+		 * that is just being created */
+		ret = regulator_resolve_supply(rdev);
+		if (!ret)
+			ret = set_machine_constraints(rdev, constraints);
+		else
+			rdev_dbg(rdev, "unable to resolve supply early: %pe\n",
+				 ERR_PTR(ret));
+	}
 	if (ret < 0)
 		goto wash;