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* [PATCH 0/2] regulator: vctrl: Avoid lockdep warning in enable/disable ops
@ 2021-08-25  3:37 Chen-Yu Tsai
  2021-08-25  3:37 ` [PATCH 1/2] regulator: vctrl: Use locked regulator_get_voltage in probe path Chen-Yu Tsai
                   ` (2 more replies)
  0 siblings, 3 replies; 5+ messages in thread
From: Chen-Yu Tsai @ 2021-08-25  3:37 UTC (permalink / raw)
  To: Mark Brown, Liam Girdwood
  Cc: Chen-Yu Tsai, Brian Norris, linux-kernel, linux-rockchip,
	linux-arm-kernel

Hi,

Here are a couple fixes for vctrl-regulator. This driver is only used
RK3399-based Chromebooks.

Patch one fixes a misuse of the regulator API, which was found while
tracing the code to fix the lockdep warning.

Patch two fixes a lockdep warning and actual (not easy to reproduce)
deadlock.

Please have a look. The are no dependencies between the two patches.


Additionally, I believe it would make sense to implement the voltage
stepping feature for all regulators in the core. Then we could move
away from vctrl-regulator. Right now it is only done for coupled
regulators.


Regards
ChenYu


Chen-Yu Tsai (2):
  regulator: vctrl: Use locked regulator_get_voltage in probe path
  regulator: vctrl: Avoid lockdep warning in enable/disable ops

 drivers/regulator/vctrl-regulator.c | 73 +++++++++++++++++------------
 1 file changed, 43 insertions(+), 30 deletions(-)

-- 
2.33.0.rc2.250.ged5fa647cd-goog


^ permalink raw reply	[flat|nested] 5+ messages in thread

* [PATCH 1/2] regulator: vctrl: Use locked regulator_get_voltage in probe path
  2021-08-25  3:37 [PATCH 0/2] regulator: vctrl: Avoid lockdep warning in enable/disable ops Chen-Yu Tsai
@ 2021-08-25  3:37 ` Chen-Yu Tsai
  2021-08-25  3:37 ` [PATCH 2/2] regulator: vctrl: Avoid lockdep warning in enable/disable ops Chen-Yu Tsai
  2021-08-25 15:18 ` [PATCH 0/2] " Mark Brown
  2 siblings, 0 replies; 5+ messages in thread
From: Chen-Yu Tsai @ 2021-08-25  3:37 UTC (permalink / raw)
  To: Mark Brown, Liam Girdwood
  Cc: Chen-Yu Tsai, Brian Norris, linux-kernel, linux-rockchip,
	linux-arm-kernel

In commit e9153311491d ("regulator: vctrl-regulator: Avoid deadlock getting
and setting the voltage"), all calls to get/set the voltage of the
control regulator were switched to unlocked versions to avoid deadlocks.
However, the call in the probe path is done without regulator locks
held. In this case the locked version should be used.

Switch back to the locked regulator_get_voltage() in the probe path to
avoid any mishaps.

Fixes: e9153311491d ("regulator: vctrl-regulator: Avoid deadlock getting and setting the voltage")
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
---
 drivers/regulator/vctrl-regulator.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/regulator/vctrl-regulator.c b/drivers/regulator/vctrl-regulator.c
index cbadb1c99679..93d33201ffe0 100644
--- a/drivers/regulator/vctrl-regulator.c
+++ b/drivers/regulator/vctrl-regulator.c
@@ -490,7 +490,8 @@ static int vctrl_probe(struct platform_device *pdev)
 		if (ret)
 			return ret;
 
-		ctrl_uV = regulator_get_voltage_rdev(vctrl->ctrl_reg->rdev);
+		/* Use locked consumer API when not in regulator framework */
+		ctrl_uV = regulator_get_voltage(vctrl->ctrl_reg);
 		if (ctrl_uV < 0) {
 			dev_err(&pdev->dev, "failed to get control voltage\n");
 			return ctrl_uV;
-- 
2.33.0.rc2.250.ged5fa647cd-goog


^ permalink raw reply	[flat|nested] 5+ messages in thread

* [PATCH 2/2] regulator: vctrl: Avoid lockdep warning in enable/disable ops
  2021-08-25  3:37 [PATCH 0/2] regulator: vctrl: Avoid lockdep warning in enable/disable ops Chen-Yu Tsai
  2021-08-25  3:37 ` [PATCH 1/2] regulator: vctrl: Use locked regulator_get_voltage in probe path Chen-Yu Tsai
@ 2021-08-25  3:37 ` Chen-Yu Tsai
  2021-08-25 15:18 ` [PATCH 0/2] " Mark Brown
  2 siblings, 0 replies; 5+ messages in thread
From: Chen-Yu Tsai @ 2021-08-25  3:37 UTC (permalink / raw)
  To: Mark Brown, Liam Girdwood
  Cc: Chen-Yu Tsai, Brian Norris, linux-kernel, linux-rockchip,
	linux-arm-kernel

vctrl_enable() and vctrl_disable() call regulator_enable() and
regulator_disable(), respectively. However, vctrl_* are regulator ops
and should not be calling the locked regulator APIs. Doing so results in
a lockdep warning.

Instead of exporting more internal regulator ops, model the ctrl supply
as an actual supply to vctrl-regulator. At probe time this driver still
needs to use the consumer API to fetch its constraints, but otherwise
lets the regulator core handle the upstream supply for it.

The enable/disable/is_enabled ops are not removed, but now only track
state internally. This preserves the original behavior with the ops
being available, but one could argue that the original behavior was
already incorrect: the internal state would not match the upstream
supply if that supply had another consumer that enabled the supply,
while vctrl-regulator was not enabled.

The lockdep warning is as follows:

	WARNING: possible circular locking dependency detected
	5.14.0-rc6 #2 Not tainted
	------------------------------------------------------
	swapper/0/1 is trying to acquire lock:
	ffffffc011306d00 (regulator_list_mutex){+.+.}-{3:3}, at:
		regulator_lock_dependent (arch/arm64/include/asm/current.h:19
					  include/linux/ww_mutex.h:111
					  drivers/regulator/core.c:329)

	but task is already holding lock:
	ffffff8004a77160 (regulator_ww_class_mutex){+.+.}-{3:3}, at:
		regulator_lock_recursive (drivers/regulator/core.c:156
					  drivers/regulator/core.c:263)

	which lock already depends on the new lock.

	the existing dependency chain (in reverse order) is:

	-> #2 (regulator_ww_class_mutex){+.+.}-{3:3}:
	__mutex_lock_common (include/asm-generic/atomic-instrumented.h:606
			     include/asm-generic/atomic-long.h:29
			     kernel/locking/mutex.c:103
			     kernel/locking/mutex.c:144
			     kernel/locking/mutex.c:963)
	ww_mutex_lock (kernel/locking/mutex.c:1199)
	regulator_lock_recursive (drivers/regulator/core.c:156
				  drivers/regulator/core.c:263)
	regulator_lock_dependent (drivers/regulator/core.c:343)
	regulator_enable (drivers/regulator/core.c:2808)
	set_machine_constraints (drivers/regulator/core.c:1536)
	regulator_register (drivers/regulator/core.c:5486)
	devm_regulator_register (drivers/regulator/devres.c:196)
	reg_fixed_voltage_probe (drivers/regulator/fixed.c:289)
	platform_probe (drivers/base/platform.c:1427)
	[...]

	-> #1 (regulator_ww_class_acquire){+.+.}-{0:0}:
	regulator_lock_dependent (include/linux/ww_mutex.h:129
				  drivers/regulator/core.c:329)
	regulator_enable (drivers/regulator/core.c:2808)
	set_machine_constraints (drivers/regulator/core.c:1536)
	regulator_register (drivers/regulator/core.c:5486)
	devm_regulator_register (drivers/regulator/devres.c:196)
	reg_fixed_voltage_probe (drivers/regulator/fixed.c:289)
	[...]

	-> #0 (regulator_list_mutex){+.+.}-{3:3}:
	__lock_acquire (kernel/locking/lockdep.c:3052 (discriminator 4)
			kernel/locking/lockdep.c:3174 (discriminator 4)
			kernel/locking/lockdep.c:3789 (discriminator 4)
			kernel/locking/lockdep.c:5015 (discriminator 4))
	lock_acquire (arch/arm64/include/asm/percpu.h:39
		      kernel/locking/lockdep.c:438
		      kernel/locking/lockdep.c:5627)
	__mutex_lock_common (include/asm-generic/atomic-instrumented.h:606
			     include/asm-generic/atomic-long.h:29
			     kernel/locking/mutex.c:103
			     kernel/locking/mutex.c:144
			     kernel/locking/mutex.c:963)
	mutex_lock_nested (kernel/locking/mutex.c:1125)
	regulator_lock_dependent (arch/arm64/include/asm/current.h:19
				  include/linux/ww_mutex.h:111
				  drivers/regulator/core.c:329)
	regulator_enable (drivers/regulator/core.c:2808)
	vctrl_enable (drivers/regulator/vctrl-regulator.c:400)
	_regulator_do_enable (drivers/regulator/core.c:2617)
	_regulator_enable (drivers/regulator/core.c:2764)
	regulator_enable (drivers/regulator/core.c:308
			  drivers/regulator/core.c:2809)
	_set_opp (drivers/opp/core.c:819 drivers/opp/core.c:1072)
	dev_pm_opp_set_rate (drivers/opp/core.c:1164)
	set_target (drivers/cpufreq/cpufreq-dt.c:62)
	__cpufreq_driver_target (drivers/cpufreq/cpufreq.c:2216
				 drivers/cpufreq/cpufreq.c:2271)
	cpufreq_online (drivers/cpufreq/cpufreq.c:1488 (discriminator 2))
	cpufreq_add_dev (drivers/cpufreq/cpufreq.c:1563)
	subsys_interface_register (drivers/base/bus.c:?)
	cpufreq_register_driver (drivers/cpufreq/cpufreq.c:2819)
	dt_cpufreq_probe (drivers/cpufreq/cpufreq-dt.c:344)
	[...]

	other info that might help us debug this:

	Chain exists of:
	  regulator_list_mutex --> regulator_ww_class_acquire --> regulator_ww_class_mutex

	 Possible unsafe locking scenario:

	       CPU0                    CPU1
	       ----                    ----
	  lock(regulator_ww_class_mutex);
				       lock(regulator_ww_class_acquire);
				       lock(regulator_ww_class_mutex);
	  lock(regulator_list_mutex);

	 *** DEADLOCK ***

	6 locks held by swapper/0/1:
	#0: ffffff8002d32188 (&dev->mutex){....}-{3:3}, at:
		__device_driver_lock (drivers/base/dd.c:1030)
	#1: ffffffc0111a0520 (cpu_hotplug_lock){++++}-{0:0}, at:
		cpufreq_register_driver (drivers/cpufreq/cpufreq.c:2792 (discriminator 2))
	#2: ffffff8002a8d918 (subsys mutex#9){+.+.}-{3:3}, at:
		subsys_interface_register (drivers/base/bus.c:1033)
	#3: ffffff800341bb90 (&policy->rwsem){+.+.}-{3:3}, at:
		cpufreq_online (include/linux/bitmap.h:285
				include/linux/cpumask.h:405
				drivers/cpufreq/cpufreq.c:1399)
	#4: ffffffc011f0b7b8 (regulator_ww_class_acquire){+.+.}-{0:0}, at:
		regulator_enable (drivers/regulator/core.c:2808)
	#5: ffffff8004a77160 (regulator_ww_class_mutex){+.+.}-{3:3}, at:
		regulator_lock_recursive (drivers/regulator/core.c:156
		drivers/regulator/core.c:263)

	stack backtrace:
	CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.14.0-rc6 #2 7c8f8996d021ed0f65271e6aeebf7999de74a9fa
	Hardware name: Google Scarlet (DT)
	Call trace:
	dump_backtrace (arch/arm64/kernel/stacktrace.c:161)
	show_stack (arch/arm64/kernel/stacktrace.c:218)
	dump_stack_lvl (lib/dump_stack.c:106 (discriminator 2))
	dump_stack (lib/dump_stack.c:113)
	print_circular_bug (kernel/locking/lockdep.c:?)
	check_noncircular (kernel/locking/lockdep.c:?)
	__lock_acquire (kernel/locking/lockdep.c:3052 (discriminator 4)
			kernel/locking/lockdep.c:3174 (discriminator 4)
			kernel/locking/lockdep.c:3789 (discriminator 4)
			kernel/locking/lockdep.c:5015 (discriminator 4))
	lock_acquire (arch/arm64/include/asm/percpu.h:39
		      kernel/locking/lockdep.c:438
		      kernel/locking/lockdep.c:5627)
	__mutex_lock_common (include/asm-generic/atomic-instrumented.h:606
			     include/asm-generic/atomic-long.h:29
			     kernel/locking/mutex.c:103
			     kernel/locking/mutex.c:144
			     kernel/locking/mutex.c:963)
	mutex_lock_nested (kernel/locking/mutex.c:1125)
	regulator_lock_dependent (arch/arm64/include/asm/current.h:19
				  include/linux/ww_mutex.h:111
				  drivers/regulator/core.c:329)
	regulator_enable (drivers/regulator/core.c:2808)
	vctrl_enable (drivers/regulator/vctrl-regulator.c:400)
	_regulator_do_enable (drivers/regulator/core.c:2617)
	_regulator_enable (drivers/regulator/core.c:2764)
	regulator_enable (drivers/regulator/core.c:308
			  drivers/regulator/core.c:2809)
	_set_opp (drivers/opp/core.c:819 drivers/opp/core.c:1072)
	dev_pm_opp_set_rate (drivers/opp/core.c:1164)
	set_target (drivers/cpufreq/cpufreq-dt.c:62)
	__cpufreq_driver_target (drivers/cpufreq/cpufreq.c:2216
				 drivers/cpufreq/cpufreq.c:2271)
	cpufreq_online (drivers/cpufreq/cpufreq.c:1488 (discriminator 2))
	cpufreq_add_dev (drivers/cpufreq/cpufreq.c:1563)
	subsys_interface_register (drivers/base/bus.c:?)
	cpufreq_register_driver (drivers/cpufreq/cpufreq.c:2819)
	dt_cpufreq_probe (drivers/cpufreq/cpufreq-dt.c:344)
	[...]

Reported-by: Brian Norris <briannorris@chromium.org>
Fixes: f8702f9e4aa7 ("regulator: core: Use ww_mutex for regulators locking")
Fixes: e9153311491d ("regulator: vctrl-regulator: Avoid deadlock getting and setting the voltage")
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
---

Mark,

checkpatch.pl gives a few style check issues about parenthesis alighment
around regulator_set_voltage_rdev() invocations, which were the result of
the previous switch over from regulator_set_voltage() to
regulator_set_voltage_rdev().

Not sure if you want those fixed up in the same patch, or maybe in a
followup one?

---
 drivers/regulator/vctrl-regulator.c | 72 +++++++++++++++++------------
 1 file changed, 42 insertions(+), 30 deletions(-)

diff --git a/drivers/regulator/vctrl-regulator.c b/drivers/regulator/vctrl-regulator.c
index 93d33201ffe0..d2a37978fc3a 100644
--- a/drivers/regulator/vctrl-regulator.c
+++ b/drivers/regulator/vctrl-regulator.c
@@ -37,7 +37,6 @@ struct vctrl_voltage_table {
 struct vctrl_data {
 	struct regulator_dev *rdev;
 	struct regulator_desc desc;
-	struct regulator *ctrl_reg;
 	bool enabled;
 	unsigned int min_slew_down_rate;
 	unsigned int ovp_threshold;
@@ -82,7 +81,12 @@ static int vctrl_calc_output_voltage(struct vctrl_data *vctrl, int ctrl_uV)
 static int vctrl_get_voltage(struct regulator_dev *rdev)
 {
 	struct vctrl_data *vctrl = rdev_get_drvdata(rdev);
-	int ctrl_uV = regulator_get_voltage_rdev(vctrl->ctrl_reg->rdev);
+	int ctrl_uV;
+
+	if (!rdev->supply)
+		return -EPROBE_DEFER;
+
+	ctrl_uV = regulator_get_voltage_rdev(rdev->supply->rdev);
 
 	return vctrl_calc_output_voltage(vctrl, ctrl_uV);
 }
@@ -92,14 +96,19 @@ static int vctrl_set_voltage(struct regulator_dev *rdev,
 			     unsigned int *selector)
 {
 	struct vctrl_data *vctrl = rdev_get_drvdata(rdev);
-	struct regulator *ctrl_reg = vctrl->ctrl_reg;
-	int orig_ctrl_uV = regulator_get_voltage_rdev(ctrl_reg->rdev);
-	int uV = vctrl_calc_output_voltage(vctrl, orig_ctrl_uV);
+	int orig_ctrl_uV;
+	int uV;
 	int ret;
 
+	if (!rdev->supply)
+		return -EPROBE_DEFER;
+
+	orig_ctrl_uV = regulator_get_voltage_rdev(rdev->supply->rdev);
+	uV = vctrl_calc_output_voltage(vctrl, orig_ctrl_uV);
+
 	if (req_min_uV >= uV || !vctrl->ovp_threshold)
 		/* voltage rising or no OVP */
-		return regulator_set_voltage_rdev(ctrl_reg->rdev,
+		return regulator_set_voltage_rdev(rdev->supply->rdev,
 			vctrl_calc_ctrl_voltage(vctrl, req_min_uV),
 			vctrl_calc_ctrl_voltage(vctrl, req_max_uV),
 			PM_SUSPEND_ON);
@@ -117,7 +126,7 @@ static int vctrl_set_voltage(struct regulator_dev *rdev,
 		next_uV = max_t(int, req_min_uV, uV - max_drop_uV);
 		next_ctrl_uV = vctrl_calc_ctrl_voltage(vctrl, next_uV);
 
-		ret = regulator_set_voltage_rdev(ctrl_reg->rdev,
+		ret = regulator_set_voltage_rdev(rdev->supply->rdev,
 					    next_ctrl_uV,
 					    next_ctrl_uV,
 					    PM_SUSPEND_ON);
@@ -134,7 +143,7 @@ static int vctrl_set_voltage(struct regulator_dev *rdev,
 
 err:
 	/* Try to go back to original voltage */
-	regulator_set_voltage_rdev(ctrl_reg->rdev, orig_ctrl_uV, orig_ctrl_uV,
+	regulator_set_voltage_rdev(rdev->supply->rdev, orig_ctrl_uV, orig_ctrl_uV,
 				   PM_SUSPEND_ON);
 
 	return ret;
@@ -151,16 +160,18 @@ static int vctrl_set_voltage_sel(struct regulator_dev *rdev,
 				 unsigned int selector)
 {
 	struct vctrl_data *vctrl = rdev_get_drvdata(rdev);
-	struct regulator *ctrl_reg = vctrl->ctrl_reg;
 	unsigned int orig_sel = vctrl->sel;
 	int ret;
 
+	if (!rdev->supply)
+		return -EPROBE_DEFER;
+
 	if (selector >= rdev->desc->n_voltages)
 		return -EINVAL;
 
 	if (selector >= vctrl->sel || !vctrl->ovp_threshold) {
 		/* voltage rising or no OVP */
-		ret = regulator_set_voltage_rdev(ctrl_reg->rdev,
+		ret = regulator_set_voltage_rdev(rdev->supply->rdev,
 					    vctrl->vtable[selector].ctrl,
 					    vctrl->vtable[selector].ctrl,
 					    PM_SUSPEND_ON);
@@ -179,7 +190,7 @@ static int vctrl_set_voltage_sel(struct regulator_dev *rdev,
 		else
 			next_sel = vctrl->vtable[vctrl->sel].ovp_min_sel;
 
-		ret = regulator_set_voltage_rdev(ctrl_reg->rdev,
+		ret = regulator_set_voltage_rdev(rdev->supply->rdev,
 					    vctrl->vtable[next_sel].ctrl,
 					    vctrl->vtable[next_sel].ctrl,
 					    PM_SUSPEND_ON);
@@ -202,7 +213,7 @@ static int vctrl_set_voltage_sel(struct regulator_dev *rdev,
 err:
 	if (vctrl->sel != orig_sel) {
 		/* Try to go back to original voltage */
-		if (!regulator_set_voltage_rdev(ctrl_reg->rdev,
+		if (!regulator_set_voltage_rdev(rdev->supply->rdev,
 					   vctrl->vtable[orig_sel].ctrl,
 					   vctrl->vtable[orig_sel].ctrl,
 					   PM_SUSPEND_ON))
@@ -234,10 +245,6 @@ static int vctrl_parse_dt(struct platform_device *pdev,
 	u32 pval;
 	u32 vrange_ctrl[2];
 
-	vctrl->ctrl_reg = devm_regulator_get(&pdev->dev, "ctrl");
-	if (IS_ERR(vctrl->ctrl_reg))
-		return PTR_ERR(vctrl->ctrl_reg);
-
 	ret = of_property_read_u32(np, "ovp-threshold-percent", &pval);
 	if (!ret) {
 		vctrl->ovp_threshold = pval;
@@ -315,11 +322,11 @@ static int vctrl_cmp_ctrl_uV(const void *a, const void *b)
 	return at->ctrl - bt->ctrl;
 }
 
-static int vctrl_init_vtable(struct platform_device *pdev)
+static int vctrl_init_vtable(struct platform_device *pdev,
+			     struct regulator *ctrl_reg)
 {
 	struct vctrl_data *vctrl = platform_get_drvdata(pdev);
 	struct regulator_desc *rdesc = &vctrl->desc;
-	struct regulator *ctrl_reg = vctrl->ctrl_reg;
 	struct vctrl_voltage_range *vrange_ctrl = &vctrl->vrange.ctrl;
 	int n_voltages;
 	int ctrl_uV;
@@ -395,23 +402,19 @@ static int vctrl_init_vtable(struct platform_device *pdev)
 static int vctrl_enable(struct regulator_dev *rdev)
 {
 	struct vctrl_data *vctrl = rdev_get_drvdata(rdev);
-	int ret = regulator_enable(vctrl->ctrl_reg);
 
-	if (!ret)
-		vctrl->enabled = true;
+	vctrl->enabled = true;
 
-	return ret;
+	return 0;
 }
 
 static int vctrl_disable(struct regulator_dev *rdev)
 {
 	struct vctrl_data *vctrl = rdev_get_drvdata(rdev);
-	int ret = regulator_disable(vctrl->ctrl_reg);
 
-	if (!ret)
-		vctrl->enabled = false;
+	vctrl->enabled = false;
 
-	return ret;
+	return 0;
 }
 
 static int vctrl_is_enabled(struct regulator_dev *rdev)
@@ -447,6 +450,7 @@ static int vctrl_probe(struct platform_device *pdev)
 	struct regulator_desc *rdesc;
 	struct regulator_config cfg = { };
 	struct vctrl_voltage_range *vrange_ctrl;
+	struct regulator *ctrl_reg;
 	int ctrl_uV;
 	int ret;
 
@@ -461,15 +465,20 @@ static int vctrl_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
+	ctrl_reg = devm_regulator_get(&pdev->dev, "ctrl");
+	if (IS_ERR(ctrl_reg))
+		return PTR_ERR(ctrl_reg);
+
 	vrange_ctrl = &vctrl->vrange.ctrl;
 
 	rdesc = &vctrl->desc;
 	rdesc->name = "vctrl";
 	rdesc->type = REGULATOR_VOLTAGE;
 	rdesc->owner = THIS_MODULE;
+	rdesc->supply_name = "ctrl";
 
-	if ((regulator_get_linear_step(vctrl->ctrl_reg) == 1) ||
-	    (regulator_count_voltages(vctrl->ctrl_reg) == -EINVAL)) {
+	if ((regulator_get_linear_step(ctrl_reg) == 1) ||
+	    (regulator_count_voltages(ctrl_reg) == -EINVAL)) {
 		rdesc->continuous_voltage_range = true;
 		rdesc->ops = &vctrl_ops_cont;
 	} else {
@@ -486,12 +495,12 @@ static int vctrl_probe(struct platform_device *pdev)
 	cfg.init_data = init_data;
 
 	if (!rdesc->continuous_voltage_range) {
-		ret = vctrl_init_vtable(pdev);
+		ret = vctrl_init_vtable(pdev, ctrl_reg);
 		if (ret)
 			return ret;
 
 		/* Use locked consumer API when not in regulator framework */
-		ctrl_uV = regulator_get_voltage(vctrl->ctrl_reg);
+		ctrl_uV = regulator_get_voltage(ctrl_reg);
 		if (ctrl_uV < 0) {
 			dev_err(&pdev->dev, "failed to get control voltage\n");
 			return ctrl_uV;
@@ -514,6 +523,9 @@ static int vctrl_probe(struct platform_device *pdev)
 		}
 	}
 
+	/* Drop ctrl-supply here in favor of regulator core managed supply */
+	devm_regulator_put(ctrl_reg);
+
 	vctrl->rdev = devm_regulator_register(&pdev->dev, rdesc, &cfg);
 	if (IS_ERR(vctrl->rdev)) {
 		ret = PTR_ERR(vctrl->rdev);
-- 
2.33.0.rc2.250.ged5fa647cd-goog


^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH 0/2] regulator: vctrl: Avoid lockdep warning in enable/disable ops
  2021-08-25 15:18 ` [PATCH 0/2] " Mark Brown
@ 2021-08-25 15:09   ` Mark Brown
  0 siblings, 0 replies; 5+ messages in thread
From: Mark Brown @ 2021-08-25 15:09 UTC (permalink / raw)
  To: Chen-Yu Tsai, Liam Girdwood
  Cc: Brian Norris, linux-rockchip, linux-arm-kernel, linux-kernel

On Wed, 25 Aug 2021 11:37:02 +0800, Chen-Yu Tsai wrote:
> Here are a couple fixes for vctrl-regulator. This driver is only used
> RK3399-based Chromebooks.
> 
> Patch one fixes a misuse of the regulator API, which was found while
> tracing the code to fix the lockdep warning.
> 
> Patch two fixes a lockdep warning and actual (not easy to reproduce)
> deadlock.
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator.git for-next

Thanks!

[1/2] regulator: vctrl: Use locked regulator_get_voltage in probe path
      commit: 98e47570ba985f2310586c80409238200fa3170f
[2/2] regulator: vctrl: Avoid lockdep warning in enable/disable ops
      commit: 21e39809fd7c4b8ff3662f23e0168e87594c8ca8

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

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH 0/2] regulator: vctrl: Avoid lockdep warning in enable/disable ops
  2021-08-25  3:37 [PATCH 0/2] regulator: vctrl: Avoid lockdep warning in enable/disable ops Chen-Yu Tsai
  2021-08-25  3:37 ` [PATCH 1/2] regulator: vctrl: Use locked regulator_get_voltage in probe path Chen-Yu Tsai
  2021-08-25  3:37 ` [PATCH 2/2] regulator: vctrl: Avoid lockdep warning in enable/disable ops Chen-Yu Tsai
@ 2021-08-25 15:18 ` Mark Brown
  2021-08-25 15:09   ` Mark Brown
  2 siblings, 1 reply; 5+ messages in thread
From: Mark Brown @ 2021-08-25 15:18 UTC (permalink / raw)
  To: Chen-Yu Tsai, Liam Girdwood
  Cc: Mark Brown, Brian Norris, linux-rockchip, linux-arm-kernel, linux-kernel

On Wed, 25 Aug 2021 11:37:02 +0800, Chen-Yu Tsai wrote:
> Here are a couple fixes for vctrl-regulator. This driver is only used
> RK3399-based Chromebooks.
> 
> Patch one fixes a misuse of the regulator API, which was found while
> tracing the code to fix the lockdep warning.
> 
> Patch two fixes a lockdep warning and actual (not easy to reproduce)
> deadlock.
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator.git for-next

Thanks!

[1/2] regulator: vctrl: Use locked regulator_get_voltage in probe path
      commit: 98e47570ba985f2310586c80409238200fa3170f
[2/2] regulator: vctrl: Avoid lockdep warning in enable/disable ops
      commit: 21e39809fd7c4b8ff3662f23e0168e87594c8ca8

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

^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2021-08-25 15:27 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-08-25  3:37 [PATCH 0/2] regulator: vctrl: Avoid lockdep warning in enable/disable ops Chen-Yu Tsai
2021-08-25  3:37 ` [PATCH 1/2] regulator: vctrl: Use locked regulator_get_voltage in probe path Chen-Yu Tsai
2021-08-25  3:37 ` [PATCH 2/2] regulator: vctrl: Avoid lockdep warning in enable/disable ops Chen-Yu Tsai
2021-08-25 15:18 ` [PATCH 0/2] " Mark Brown
2021-08-25 15:09   ` Mark Brown

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