[PATCH] regulator: core: don't return error with inadequate reason

[PATCH] regulator: core: don't return error with inadequate reason

[Joonwoo Park]

drms_uA_update() always returns failure when it cannot find regulator's
input voltage.  But if hardware supports load configuration with
ops->set_load() and the input regulator isn't specified with valid reason
such as the input regulator is battery, not finding input voltage is
normal so such case should not return with an error.

Avoid such inadequate error return by checking input/output voltages
only when drms_uA_update() is about to configure load with enum based
ops->set_mode().

Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
---
I think we can get rid of ops->get_optimum_mode since *most* of regulator drivers' get_optimum_mode ops are dead code.
The only driver at least I found which has valid vaild_modes_mask with proper ops->get_optimum_mode is wm8350-regulator.c used by mach-mx31ads.c
But I believe the issue what I'm fixing here is slightly off from the matter of removing ops->get_optimum_mode.

 drivers/regulator/core.c | 36 ++++++++++++++++++------------------
 1 file changed, 18 insertions(+), 18 deletions(-)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 1eef2ec..50cb7b9 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -680,24 +680,6 @@ static int drms_uA_update(struct regulator_dev *rdev)
 	    !rdev->desc->ops->set_load)
 		return -EINVAL;
 
-	/* get output voltage */
-	output_uV = _regulator_get_voltage(rdev);
-	if (output_uV <= 0) {
-		rdev_err(rdev, "invalid output voltage found\n");
-		return -EINVAL;
-	}
-
-	/* get input voltage */
-	input_uV = 0;
-	if (rdev->supply)
-		input_uV = regulator_get_voltage(rdev->supply);
-	if (input_uV <= 0)
-		input_uV = rdev->constraints->input_uV;
-	if (input_uV <= 0) {
-		rdev_err(rdev, "invalid input voltage found\n");
-		return -EINVAL;
-	}
-
 	/* calc total requested load */
 	list_for_each_entry(sibling, &rdev->consumer_list, list)
 		current_uA += sibling->uA_load;
@@ -710,6 +692,24 @@ static int drms_uA_update(struct regulator_dev *rdev)
 		if (err < 0)
 			rdev_err(rdev, "failed to set load %d\n", current_uA);
 	} else {
+		/* get output voltage */
+		output_uV = _regulator_get_voltage(rdev);
+		if (output_uV <= 0) {
+			rdev_err(rdev, "invalid output voltage found\n");
+			return -EINVAL;
+		}
+
+		/* get input voltage */
+		input_uV = 0;
+		if (rdev->supply)
+			input_uV = regulator_get_voltage(rdev->supply);
+		if (input_uV <= 0)
+			input_uV = rdev->constraints->input_uV;
+		if (input_uV <= 0) {
+			rdev_err(rdev, "invalid input voltage found\n");
+			return -EINVAL;
+		}
+
 		/* now get the optimum mode for our new total regulator load */
 		mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
 							 output_uV, current_uA);
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
hosted by The Linux Foundation

Applied "regulator: core: don't return error with inadequate reason" to the regulator tree

[Mark Brown]

The patch

   regulator: core: don't return error with inadequate reason

has been applied to the regulator tree at

   git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator.git 

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.  

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

>From 577766175c40d4f425be47b9e70d80238e53f996 Mon Sep 17 00:00:00 2001
From: Joonwoo Park <joonwoop@codeaurora.org>
Date: Mon, 19 Sep 2016 14:46:54 -0700
Subject: [PATCH] regulator: core: don't return error with inadequate reason

drms_uA_update() always returns failure when it cannot find regulator's
input voltage.  But if hardware supports load configuration with
ops->set_load() and the input regulator isn't specified with valid reason
such as the input regulator is battery, not finding input voltage is
normal so such case should not return with an error.

Avoid such inadequate error return by checking input/output voltages
only when drms_uA_update() is about to configure load with enum based
ops->set_mode().

Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 drivers/regulator/core.c | 36 ++++++++++++++++++------------------
 1 file changed, 18 insertions(+), 18 deletions(-)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index db320e8fa865..bafcdff42872 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -679,24 +679,6 @@ static int drms_uA_update(struct regulator_dev *rdev)
 	    !rdev->desc->ops->set_load)
 		return -EINVAL;
 
-	/* get output voltage */
-	output_uV = _regulator_get_voltage(rdev);
-	if (output_uV <= 0) {
-		rdev_err(rdev, "invalid output voltage found\n");
-		return -EINVAL;
-	}
-
-	/* get input voltage */
-	input_uV = 0;
-	if (rdev->supply)
-		input_uV = regulator_get_voltage(rdev->supply);
-	if (input_uV <= 0)
-		input_uV = rdev->constraints->input_uV;
-	if (input_uV <= 0) {
-		rdev_err(rdev, "invalid input voltage found\n");
-		return -EINVAL;
-	}
-
 	/* calc total requested load */
 	list_for_each_entry(sibling, &rdev->consumer_list, list)
 		current_uA += sibling->uA_load;
@@ -709,6 +691,24 @@ static int drms_uA_update(struct regulator_dev *rdev)
 		if (err < 0)
 			rdev_err(rdev, "failed to set load %d\n", current_uA);
 	} else {
+		/* get output voltage */
+		output_uV = _regulator_get_voltage(rdev);
+		if (output_uV <= 0) {
+			rdev_err(rdev, "invalid output voltage found\n");
+			return -EINVAL;
+		}
+
+		/* get input voltage */
+		input_uV = 0;
+		if (rdev->supply)
+			input_uV = regulator_get_voltage(rdev->supply);
+		if (input_uV <= 0)
+			input_uV = rdev->constraints->input_uV;
+		if (input_uV <= 0) {
+			rdev_err(rdev, "invalid input voltage found\n");
+			return -EINVAL;
+		}
+
 		/* now get the optimum mode for our new total regulator load */
 		mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
 							 output_uV, current_uA);
-- 
2.9.3