linux-kernel - [PATCH 1/4] regulator: core: If consumers don't call regulator_set

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Date:   Tue, 14 Aug 2018 10:06:14 -0700
From:   Douglas Anderson <dianders@...omium.org>
To:     broonie@...nel.org
Cc:     linux-arm-msm@...r.kernel.org, bjorn.andersson@...aro.org,
        collinsd@...eaurora.org, swboyd@...omium.org,
        Douglas Anderson <dianders@...omium.org>,
        Liam Girdwood <lgirdwood@...il.com>,
        linux-kernel@...r.kernel.org
Subject: [PATCH 1/4] regulator: core: If consumers don't call regulator_set_load() assume max

Not all regulator consumers call regulator_set_load().  On some
regulators (like on RPMh-regulator) this could be bad since the
regulator framework will treat this as if consumer needs no load.
It's much better to assume that a dumb client needs the maximum
possible load so we get correctness first.

Signed-off-by: Douglas Anderson <dianders@...omium.org>
---

 drivers/regulator/core.c     | 10 +++++++++-
 drivers/regulator/internal.h |  1 +
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 6ed568b96c0e..a4da68775b49 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -732,6 +732,7 @@ static int drms_uA_update(struct regulator_dev *rdev)
 	struct regulator *sibling;
 	int current_uA = 0, output_uV, input_uV, err;
 	unsigned int mode;
+	bool any_unset = false;
 
 	lockdep_assert_held_once(&rdev->mutex);
 
@@ -751,11 +752,17 @@ static int drms_uA_update(struct regulator_dev *rdev)
 		return -EINVAL;
 
 	/* calc total requested load */
-	list_for_each_entry(sibling, &rdev->consumer_list, list)
+	list_for_each_entry(sibling, &rdev->consumer_list, list) {
 		current_uA += sibling->uA_load;
+		if (!sibling->uA_load_set)
+			any_unset = true;
+	}
 
 	current_uA += rdev->constraints->system_load;
 
+	if (any_unset)
+		current_uA = INT_MAX;
+
 	if (rdev->desc->ops->set_load) {
 		/* set the optimum mode for our new total regulator load */
 		err = rdev->desc->ops->set_load(rdev, current_uA);
@@ -3631,6 +3638,7 @@ int regulator_set_load(struct regulator *regulator, int uA_load)
 
 	regulator_lock(rdev);
 	regulator->uA_load = uA_load;
+	regulator->uA_load_set = true;
 	ret = drms_uA_update(rdev);
 	regulator_unlock(rdev);
 
diff --git a/drivers/regulator/internal.h b/drivers/regulator/internal.h
index 943926a156f2..f05c75c59ef4 100644
--- a/drivers/regulator/internal.h
+++ b/drivers/regulator/internal.h
@@ -41,6 +41,7 @@ struct regulator {
 	struct list_head list;
 	unsigned int always_on:1;
 	unsigned int bypass:1;
+	bool uA_load_set;
 	int uA_load;
 	struct regulator_voltage voltage[REGULATOR_STATES_NUM];
 	const char *supply_name;
-- 
2.18.0.865.gffc8e1a3cd6-goog