power: regulator: Add limits checking while setting voltage and current

Currently the specific set ops functions are directly called without any check for voltage/current limits for a regulator. Check for them and proceed.

Signed-off-by Keerthy <[email protected]>

---
  drivers/power/regulator/regulator-uclass.c | 10 ++++++++++
  1 file changed, 10 insertions(+)

drivers/power/regulator/regulator-uclass.c +5 -0

index 4434e36..089455e 100644
@@ -41,6 +41,11 @@ int regulator_get_value(struct udevice *dev)
  int regulator_set_value(struct udevice *dev, int uV)
  {
  	const struct dm_regulator_ops *ops = dev_get_driver_ops(dev);
+	struct dm_regulator_uclass_platdata *uc_pdata;
+
+	uc_pdata = dev_get_uclass_platdata(dev);
+	if (uV < uc_pdata->min_uV || uV > uc_pdata->max_uV)
+		return -EINVAL;
 
  	if (!ops || !ops->set_value)
  		return -ENOSYS;

@@ -61,6 +66,11 @@ int regulator_get_current(struct udevice *dev)
  int regulator_set_current(struct udevice *dev, int uA)

Hello Keerthy,

Quoted 26 lines · Keerthy

Currently the specific set ops functions are directly called without any check for voltage/current limits for a regulator. Check for them and proceed.

Signed-off-by Keerthy <[email protected]>

---
  drivers/power/regulator/regulator-uclass.c | 10 ++++++++++
  1 file changed, 10 insertions(+)

drivers/power/regulator/regulator-uclass.c +5 -0

index 4434e36..089455e 100644
@@ -41,6 +41,11 @@ int regulator_get_value(struct udevice *dev)
  int regulator_set_value(struct udevice *dev, int uV)
  {
      const struct dm_regulator_ops *ops = dev_get_driver_ops(dev);
+    struct dm_regulator_uclass_platdata *uc_pdata;
+
+    uc_pdata = dev_get_uclass_platdata(dev);
+    if (uV < uc_pdata->min_uV || uV > uc_pdata->max_uV)
+        return -EINVAL;
        if (!ops || !ops->set_value)
          return -ENOSYS;

drivers/power/regulator/regulator-uclass.c int regulator_get_current(struct udevice *dev) · line 75

Quoted 10 lines

drivers/power/regulator/regulator-uclass.c +5 -0

@@ -61,6 +66,11 @@ int regulator_get_current(struct udevice *dev)
  int regulator_set_current(struct udevice *dev, int uA)
  {
      const struct dm_regulator_ops *ops = dev_get_driver_ops(dev);
+    struct dm_regulator_uclass_platdata *uc_pdata;
+
+    uc_pdata = dev_get_uclass_platdata(dev);
+    if (uA < uc_pdata->min_uA || uA > uc_pdata->max_uA)
+        return -EINVAL;
        if (!ops || !ops->set_current)
          return -ENOSYS;

Adding those two checks will conflict with "force" option for cmd/regulator.c:283.
There was value range checking in the command's code, but it was left unchecked
for regulator direct calls.

This change is good, but then maybe the "force" option should be removed from command,
or API's prototypes should be updated by force flag argument?

I assumed that this option could be useful for quick over-voltage setting (until reboot),
since usually (min_uV == max_uV) - the voltage can't be changed in any range.

The driver should take care about ignore it or not, however probably nobody used this.

Of course this could potentially damage the device by wrong use, which can be also made by passing the force flag as an argument - by mistake.

What do you thing about, update the dm_regulator_ops by:

- int (*set_value)(struct udevice *dev, int uV, int flag);
- int (*set_current)(struct udevice *dev, int uA, int flag);

and also new flag to the present defined:

- REGULATOR_FLAG_FORCE = 1 << 2

This requires more work, but will provide the functionality in a proper way.

Best regards,

Quoted 58 lines · Przemyslaw Marczak

Hello Keerthy,

Quoted 26 lines · Keerthy

Currently the specific set ops functions are directly called without any check for voltage/current limits for a regulator. Check for them and proceed.

Signed-off-by Keerthy <[email protected]>

---
  drivers/power/regulator/regulator-uclass.c | 10 ++++++++++
  1 file changed, 10 insertions(+)

drivers/power/regulator/regulator-uclass.c +5 -0

index 4434e36..089455e 100644
@@ -41,6 +41,11 @@ int regulator_get_value(struct udevice *dev)
  int regulator_set_value(struct udevice *dev, int uV)
  {
      const struct dm_regulator_ops *ops = dev_get_driver_ops(dev);
+    struct dm_regulator_uclass_platdata *uc_pdata;
+
+    uc_pdata = dev_get_uclass_platdata(dev);
+    if (uV < uc_pdata->min_uV || uV > uc_pdata->max_uV)
+        return -EINVAL;
        if (!ops || !ops->set_value)
          return -ENOSYS;

drivers/power/regulator/regulator-uclass.c int regulator_get_current(struct udevice *dev) · line 75

Quoted 10 lines

drivers/power/regulator/regulator-uclass.c +5 -0

@@ -61,6 +66,11 @@ int regulator_get_current(struct udevice *dev)
  int regulator_set_current(struct udevice *dev, int uA)
  {
      const struct dm_regulator_ops *ops = dev_get_driver_ops(dev);
+    struct dm_regulator_uclass_platdata *uc_pdata;
+
+    uc_pdata = dev_get_uclass_platdata(dev);
+    if (uA < uc_pdata->min_uA || uA > uc_pdata->max_uA)
+        return -EINVAL;
        if (!ops || !ops->set_current)
          return -ENOSYS;

Adding those two checks will conflict with "force" option for cmd/regulator.c:283.
There was value range checking in the command's code, but it was left unchecked
for regulator direct calls.

This change is good, but then maybe the "force" option should be removed from command,
or API's prototypes should be updated by force flag argument?

I assumed that this option could be useful for quick over-voltage setting (until reboot),
since usually (min_uV == max_uV) - the voltage can't be changed in any range.

The driver should take care about ignore it or not, however probably nobody used this.

Quoted 8 lines

Of course this could potentially damage the device by wrong use, which can be also made by passing the force flag as an argument - by mistake.

What do you thing about, update the dm_regulator_ops by:

- int (*set_value)(struct udevice *dev, int uV, int flag);
- int (*set_current)(struct udevice *dev, int uA, int flag);

Quoted 7 lines

and also new flag to the present defined:

- REGULATOR_FLAG_FORCE = 1 << 2

This requires more work, but will provide the functionality in a proper way.

I do not know cmd_regulator is the right place to check for min_uV and max_uV. dm_regulator_uclass_platdata has both the limits and this i feel is a perfectly valid check in generic place else we would be again checking for the same condition in every possible regulator specific drivers.

As far as the force option is concerned that i believe is more for testing and like you said can be implemented by setting a flag.

Just take a simple case of say a driver like mmc which unknowingly requests a wrong voltage and the base driver has no check against min and max voltages and assuming the regulator driver goes ahead and sets a very high voltage. That can be catastrophic right?

Quoted 3 lines

Best regards,

Quoted 65 lines · Keerthy

Quoted 61 lines · Przemyslaw Marczak

Hello Keerthy,

Quoted 27 lines · Keerthy

Currently the specific set ops functions are directly called without any check for voltage/current limits for a regulator. Check for them and proceed.

Signed-off-by Keerthy <[email protected]>

---
  drivers/power/regulator/regulator-uclass.c | 10 ++++++++++
  1 file changed, 10 insertions(+)

drivers/power/regulator/regulator-uclass.c +5 -0

index 4434e36..089455e 100644
@@ -41,6 +41,11 @@ int regulator_get_value(struct udevice *dev)
  int regulator_set_value(struct udevice *dev, int uV)
  {
      const struct dm_regulator_ops *ops = dev_get_driver_ops(dev);
+    struct dm_regulator_uclass_platdata *uc_pdata;
+
+    uc_pdata = dev_get_uclass_platdata(dev);
+    if (uV < uc_pdata->min_uV || uV > uc_pdata->max_uV)
+        return -EINVAL;
        if (!ops || !ops->set_value)
          return -ENOSYS;

drivers/power/regulator/regulator-uclass.c int regulator_get_current(struct udevice *dev) · line 75

Quoted 10 lines

drivers/power/regulator/regulator-uclass.c +5 -0

@@ -61,6 +66,11 @@ int regulator_get_current(struct udevice *dev)
  int regulator_set_current(struct udevice *dev, int uA)
  {
      const struct dm_regulator_ops *ops = dev_get_driver_ops(dev);
+    struct dm_regulator_uclass_platdata *uc_pdata;
+
+    uc_pdata = dev_get_uclass_platdata(dev);
+    if (uA < uc_pdata->min_uA || uA > uc_pdata->max_uA)
+        return -EINVAL;
        if (!ops || !ops->set_current)
          return -ENOSYS;

Adding those two checks will conflict with "force" option for cmd/regulator.c:283.
There was value range checking in the command's code, but it was left unchecked
for regulator direct calls.

This change is good, but then maybe the "force" option should be removed from command,
or API's prototypes should be updated by force flag argument?

I assumed that this option could be useful for quick over-voltage setting (until reboot),
since usually (min_uV == max_uV) - the voltage can't be changed in any range.

The driver should take care about ignore it or not, however probably nobody used this.

Quoted 8 lines

Quoted 8 lines

Of course this could potentially damage the device by wrong use, which can be also made by passing the force flag as an argument - by mistake.

What do you thing about, update the dm_regulator_ops by:

- int (*set_value)(struct udevice *dev, int uV, int flag);
- int (*set_current)(struct udevice *dev, int uA, int flag);

I personally do not like setting an extra flag everywhere just because we want to support force option.

I would rather have 2 functions like:

int (*force_set_value)(struct udevice *dev, int uV); int (*force_set_current)(struct udevice *dev, int uA);

Where we can set the value ignoring the limits. But again that must be used with at most caution as setting higher voltages might end up damaging the device.

Quoted 17 lines

Quoted 9 lines

and also new flag to the present defined:

- REGULATOR_FLAG_FORCE = 1 << 2

This requires more work, but will provide the functionality in a proper way.

I do not know cmd_regulator is the right place to check for min_uV and max_uV. dm_regulator_uclass_platdata has both the limits and this i feel is a perfectly valid check in generic place else we would be again checking for the same condition in every possible regulator specific drivers.

Quoted 7 lines

As far as the force option is concerned that i believe is more for testing and like you said can be implemented by setting a flag.

Just take a simple case of say a driver like mmc which unknowingly requests a wrong voltage and the base driver has no check against min and max voltages and assuming the regulator driver goes ahead and sets a very high voltage. That can be catastrophic right?

Hi Keerthy,

Quoted 81 lines · Keerthy

Quoted 65 lines · Keerthy

Quoted 61 lines · Przemyslaw Marczak

Hello Keerthy,

Quoted 27 lines · Keerthy

Currently the specific set ops functions are directly called without any check for voltage/current limits for a regulator. Check for them and proceed.

Signed-off-by Keerthy <[email protected]>

---
  drivers/power/regulator/regulator-uclass.c | 10 ++++++++++
  1 file changed, 10 insertions(+)

drivers/power/regulator/regulator-uclass.c +5 -0

index 4434e36..089455e 100644
@@ -41,6 +41,11 @@ int regulator_get_value(struct udevice *dev)
  int regulator_set_value(struct udevice *dev, int uV)
  {
      const struct dm_regulator_ops *ops = dev_get_driver_ops(dev);
+    struct dm_regulator_uclass_platdata *uc_pdata;
+
+    uc_pdata = dev_get_uclass_platdata(dev);
+    if (uV < uc_pdata->min_uV || uV > uc_pdata->max_uV)
+        return -EINVAL;
        if (!ops || !ops->set_value)
          return -ENOSYS;

drivers/power/regulator/regulator-uclass.c int regulator_get_current(struct udevice *dev) · line 75

Quoted 10 lines

drivers/power/regulator/regulator-uclass.c +5 -0

@@ -61,6 +66,11 @@ int regulator_get_current(struct udevice *dev)
  int regulator_set_current(struct udevice *dev, int uA)
  {
      const struct dm_regulator_ops *ops = dev_get_driver_ops(dev);
+    struct dm_regulator_uclass_platdata *uc_pdata;
+
+    uc_pdata = dev_get_uclass_platdata(dev);
+    if (uA < uc_pdata->min_uA || uA > uc_pdata->max_uA)
+        return -EINVAL;
        if (!ops || !ops->set_current)
          return -ENOSYS;

Adding those two checks will conflict with "force" option for cmd/regulator.c:283.
There was value range checking in the command's code, but it was left unchecked
for regulator direct calls.

This change is good, but then maybe the "force" option should be removed from command,
or API's prototypes should be updated by force flag argument?

I assumed that this option could be useful for quick over-voltage setting (until reboot),
since usually (min_uV == max_uV) - the voltage can't be changed in any range.

The driver should take care about ignore it or not, however probably nobody used this.

Quoted 8 lines

Quoted 8 lines

Of course this could potentially damage the device by wrong use, which can be also made by passing the force flag as an argument - by mistake.

What do you thing about, update the dm_regulator_ops by:

- int (*set_value)(struct udevice *dev, int uV, int flag);
- int (*set_current)(struct udevice *dev, int uA, int flag);

I personally do not like setting an extra flag everywhere just because we want to support force option.

Quoted 8 lines

I would rather have 2 functions like:

int (*force_set_value)(struct udevice *dev, int uV); int (*force_set_current)(struct udevice *dev, int uA);

Where we can set the value ignoring the limits. But again that must be used with at most caution as setting higher voltages might end up damaging the device.

That seems OK to me.

Quoted 20 lines

Quoted 20 lines

Quoted 9 lines

and also new flag to the present defined:

- REGULATOR_FLAG_FORCE = 1 << 2

This requires more work, but will provide the functionality in a proper way.

I do not know cmd_regulator is the right place to check for min_uV and max_uV. dm_regulator_uclass_platdata has both the limits and this i feel is a perfectly valid check in generic place else we would be again checking for the same condition in every possible regulator specific drivers.

As far as the force option is concerned that i believe is more for testing and like you said can be implemented by setting a flag.

Quoted 4 lines

Quoted 4 lines

Just take a simple case of say a driver like mmc which unknowingly requests a wrong voltage and the base driver has no check against min and max voltages and assuming the regulator driver goes ahead and sets a very high voltage. That can be catastrophic right?

What is the status of this patch please?

Also it breaks tests (make tests) - can you please take a look?

Regards,
Simon

Quoted 127 lines · Simon Glass

Hi Keerthy,

Quoted 85 lines · Keerthy

Quoted 66 lines · Keerthy

Quoted 62 lines · Przemyslaw Marczak

Hello Keerthy,

Quoted 27 lines · Keerthy

Currently the specific set ops functions are directly called without any check for voltage/current limits for a regulator. Check for them and proceed.

Signed-off-by Keerthy <[email protected]>

---
  drivers/power/regulator/regulator-uclass.c | 10 ++++++++++
  1 file changed, 10 insertions(+)

drivers/power/regulator/regulator-uclass.c +5 -0

index 4434e36..089455e 100644
@@ -41,6 +41,11 @@ int regulator_get_value(struct udevice *dev)
  int regulator_set_value(struct udevice *dev, int uV)
  {
      const struct dm_regulator_ops *ops = dev_get_driver_ops(dev);
+    struct dm_regulator_uclass_platdata *uc_pdata;
+
+    uc_pdata = dev_get_uclass_platdata(dev);
+    if (uV < uc_pdata->min_uV || uV > uc_pdata->max_uV)
+        return -EINVAL;
        if (!ops || !ops->set_value)
          return -ENOSYS;

drivers/power/regulator/regulator-uclass.c int regulator_get_current(struct udevice *dev) · line 75

Quoted 10 lines

drivers/power/regulator/regulator-uclass.c +5 -0

@@ -61,6 +66,11 @@ int regulator_get_current(struct udevice *dev)
  int regulator_set_current(struct udevice *dev, int uA)
  {
      const struct dm_regulator_ops *ops = dev_get_driver_ops(dev);
+    struct dm_regulator_uclass_platdata *uc_pdata;
+
+    uc_pdata = dev_get_uclass_platdata(dev);
+    if (uA < uc_pdata->min_uA || uA > uc_pdata->max_uA)
+        return -EINVAL;
        if (!ops || !ops->set_current)
          return -ENOSYS;

Adding those two checks will conflict with "force" option for cmd/regulator.c:283.
There was value range checking in the command's code, but it was left unchecked
for regulator direct calls.

This change is good, but then maybe the "force" option should be removed
from command,
or API's prototypes should be updated by force flag argument?

I assumed that this option could be useful for quick over-voltage setting (until reboot),
since usually (min_uV == max_uV) - the voltage can't be changed in any range.

The driver should take care about ignore it or not, however probably nobody used this.

Quoted 8 lines

Quoted 8 lines

Of course this could potentially damage the device by wrong use, which can be also made by passing the force flag as an argument - by mistake.

What do you thing about, update the dm_regulator_ops by:

- int (*set_value)(struct udevice *dev, int uV, int flag);
- int (*set_current)(struct udevice *dev, int uA, int flag);

I personally do not like setting an extra flag everywhere just because we
want to support force option.

I would rather have 2 functions like:

Quoted 8 lines

int (*force_set_value)(struct udevice *dev, int uV); int (*force_set_current)(struct udevice *dev, int uA);

Where we can set the value ignoring the limits. But again that must be used
with at most caution as setting higher voltages might end up damaging the
device.

That seems OK to me.

Quoted 27 lines

Quoted 27 lines

Quoted 10 lines

and also new flag to the present defined:

- REGULATOR_FLAG_FORCE = 1 << 2

This requires more work, but will provide the functionality in a proper
way.

I do not know cmd_regulator is the right place to check for min_uV and max_uV. dm_regulator_uclass_platdata has both the limits and this i feel
is a perfectly valid check in generic place else we would be again checking for the same condition in every possible regulator specific drivers.

As far as the force option is concerned that i believe is more for testing and like you said can be implemented by setting a flag.

Just take a simple case of say a driver like mmc which unknowingly requests a wrong voltage and the base driver has no check against min and max voltages and assuming the regulator driver goes ahead and sets a
very high voltage. That can be catastrophic right?

Quoted 3 lines

What is the status of this patch please?

Also it breaks tests (make tests) - can you please take a look?

Sure Simon. It was hanging somehow. I will redo and repost it.

Quoted 5 lines

Regards,
Simon