[RFC,v3,04/10] OPP: Add and export helper to update voltage
diff mbox series

Message ID 20200127200350.24465-5-sibis@codeaurora.org
State New
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Series
  • DDR/L3 Scaling support on SDM845 and SC7180 SoCs
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Commit Message

Sibi Sankar Jan. 27, 2020, 8:03 p.m. UTC
Add and export 'dev_pm_opp_update_voltage' to find and update voltage
of an opp for a given frequency. This will be useful to update the opps
with voltages read back from firmware.

Signed-off-by: Sibi Sankar <sibis@codeaurora.org>
---
 drivers/opp/core.c     | 55 ++++++++++++++++++++++++++++++++++++++++++
 include/linux/pm_opp.h | 10 ++++++++
 2 files changed, 65 insertions(+)

Comments

Matthias Kaehlcke Jan. 28, 2020, 9:33 p.m. UTC | #1
Hi Sibi,

On Tue, Jan 28, 2020 at 01:33:44AM +0530, Sibi Sankar wrote:
> Add and export 'dev_pm_opp_update_voltage' to find and update voltage
> of an opp for a given frequency. This will be useful to update the opps
> with voltages read back from firmware.
> 
> Signed-off-by: Sibi Sankar <sibis@codeaurora.org>
> ---
>  drivers/opp/core.c     | 55 ++++++++++++++++++++++++++++++++++++++++++
>  include/linux/pm_opp.h | 10 ++++++++
>  2 files changed, 65 insertions(+)
> 
> diff --git a/drivers/opp/core.c b/drivers/opp/core.c
> index 9aa2a44a5d638..f241e83ec926a 100644
> --- a/drivers/opp/core.c
> +++ b/drivers/opp/core.c
> @@ -2503,6 +2503,61 @@ int dev_pm_opp_disable(struct device *dev, unsigned long freq)
>  }
>  EXPORT_SYMBOL_GPL(dev_pm_opp_disable);
>  
> +/**
> + * dev_pm_opp_update_voltage() - Find and update voltage

The comment should mention that this is done for an OPP.

Maybe omit the 'find' part here and just say 'Update the voltage of
an OPP'?

> + * @dev:	device for which we do this operation
> + * @freq:	OPP frequency to update voltage
> + * @u_volt:	voltage requested for this opp
> + *
> + * Find and update voltage of a disabled opp corresponding to the given
> + * frequency. This is useful only for devices with single power supply.
> + *
> + * Return: 0 if modification was successful or a negative error value.
> + */
> +int dev_pm_opp_update_voltage(struct device *dev, unsigned long freq,
> +			      unsigned long u_volt)
> +{
> +	struct dev_pm_opp *opp = ERR_PTR(-ENODEV);

initialization is not needed

> +	struct opp_table *opp_table;
> +	unsigned long tol;
> +	int ret = 0;
> +
> +	/* Find the opp_table */

Drop the comment, it's obvious from the code.

> +	opp_table = _find_opp_table(dev);
> +	if (IS_ERR(opp_table)) {
> +		ret = PTR_ERR(opp_table);
> +		dev_err(dev, "%s: OPP table not found (%d)\n", __func__, ret);
> +		return PTR_ERR(opp_table);

  		return ret;

> +	}
> +
> +	opp = dev_pm_opp_find_freq_exact(dev, freq, false);
> +	if (IS_ERR(opp)) {
> +		ret = PTR_ERR(opp);
> +		goto put_table;
> +	}
> +
> +	mutex_lock(&opp_table->lock);
> +
> +	/* update only if the opp is disabled */
> +	if (opp->available) {
> +		ret = -EBUSY;
> +		goto unlock;
> +	}
> +
> +	tol = u_volt * opp_table->voltage_tolerance_v1 / 100;
> +	opp->supplies[0].u_volt_min = u_volt - tol;
> +	opp->supplies[0].u_volt = u_volt;
> +	opp->supplies[0].u_volt_min = u_volt + tol;

  			.u_volt_max =

I suppose the assignments need to be done for all possible supplies,
i.e. 0 to (opp_table->regulator_count - 1).
Sibi Sankar Jan. 29, 2020, 1:49 p.m. UTC | #2
On 2020-01-29 03:03, Matthias Kaehlcke wrote:
> Hi Sibi,
> 
> On Tue, Jan 28, 2020 at 01:33:44AM +0530, Sibi Sankar wrote:
>> Add and export 'dev_pm_opp_update_voltage' to find and update voltage
>> of an opp for a given frequency. This will be useful to update the 
>> opps
>> with voltages read back from firmware.
>> 
>> Signed-off-by: Sibi Sankar <sibis@codeaurora.org>
>> ---
>>  drivers/opp/core.c     | 55 
>> ++++++++++++++++++++++++++++++++++++++++++
>>  include/linux/pm_opp.h | 10 ++++++++
>>  2 files changed, 65 insertions(+)
>> 
>> diff --git a/drivers/opp/core.c b/drivers/opp/core.c
>> index 9aa2a44a5d638..f241e83ec926a 100644
>> --- a/drivers/opp/core.c
>> +++ b/drivers/opp/core.c
>> @@ -2503,6 +2503,61 @@ int dev_pm_opp_disable(struct device *dev, 
>> unsigned long freq)
>>  }
>>  EXPORT_SYMBOL_GPL(dev_pm_opp_disable);
>> 
>> +/**
>> + * dev_pm_opp_update_voltage() - Find and update voltage
> 
> The comment should mention that this is done for an OPP.
> 
> Maybe omit the 'find' part here and just say 'Update the voltage of
> an OPP'?

sure makes sense

> 
>> + * @dev:	device for which we do this operation
>> + * @freq:	OPP frequency to update voltage
>> + * @u_volt:	voltage requested for this opp
>> + *
>> + * Find and update voltage of a disabled opp corresponding to the 
>> given
>> + * frequency. This is useful only for devices with single power 
>> supply.
>> + *
>> + * Return: 0 if modification was successful or a negative error 
>> value.
>> + */
>> +int dev_pm_opp_update_voltage(struct device *dev, unsigned long freq,
>> +			      unsigned long u_volt)
>> +{
>> +	struct dev_pm_opp *opp = ERR_PTR(-ENODEV);
> 
> initialization is not needed
> 
>> +	struct opp_table *opp_table;
>> +	unsigned long tol;
>> +	int ret = 0;
>> +
>> +	/* Find the opp_table */
> 
> Drop the comment, it's obvious from the code.
> 
>> +	opp_table = _find_opp_table(dev);
>> +	if (IS_ERR(opp_table)) {
>> +		ret = PTR_ERR(opp_table);
>> +		dev_err(dev, "%s: OPP table not found (%d)\n", __func__, ret);
>> +		return PTR_ERR(opp_table);
> 
>   		return ret;

missed that :(

> 
>> +	}
>> +
>> +	opp = dev_pm_opp_find_freq_exact(dev, freq, false);
>> +	if (IS_ERR(opp)) {
>> +		ret = PTR_ERR(opp);
>> +		goto put_table;
>> +	}
>> +
>> +	mutex_lock(&opp_table->lock);
>> +
>> +	/* update only if the opp is disabled */
>> +	if (opp->available) {
>> +		ret = -EBUSY;
>> +		goto unlock;
>> +	}
>> +
>> +	tol = u_volt * opp_table->voltage_tolerance_v1 / 100;
>> +	opp->supplies[0].u_volt_min = u_volt - tol;
>> +	opp->supplies[0].u_volt = u_volt;
>> +	opp->supplies[0].u_volt_min = u_volt + tol;
> 
>   			.u_volt_max =
> 
> I suppose the assignments need to be done for all possible supplies,
> i.e. 0 to (opp_table->regulator_count - 1).

a single value for all possible
supplies seems wrong. Anyway
will wait to see what Viresh
thinks about it.

Patch
diff mbox series

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index 9aa2a44a5d638..f241e83ec926a 100644
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -2503,6 +2503,61 @@  int dev_pm_opp_disable(struct device *dev, unsigned long freq)
 }
 EXPORT_SYMBOL_GPL(dev_pm_opp_disable);
 
+/**
+ * dev_pm_opp_update_voltage() - Find and update voltage
+ * @dev:	device for which we do this operation
+ * @freq:	OPP frequency to update voltage
+ * @u_volt:	voltage requested for this opp
+ *
+ * Find and update voltage of a disabled opp corresponding to the given
+ * frequency. This is useful only for devices with single power supply.
+ *
+ * Return: 0 if modification was successful or a negative error value.
+ */
+int dev_pm_opp_update_voltage(struct device *dev, unsigned long freq,
+			      unsigned long u_volt)
+{
+	struct dev_pm_opp *opp = ERR_PTR(-ENODEV);
+	struct opp_table *opp_table;
+	unsigned long tol;
+	int ret = 0;
+
+	/* Find the opp_table */
+	opp_table = _find_opp_table(dev);
+	if (IS_ERR(opp_table)) {
+		ret = PTR_ERR(opp_table);
+		dev_err(dev, "%s: OPP table not found (%d)\n", __func__, ret);
+		return PTR_ERR(opp_table);
+	}
+
+	opp = dev_pm_opp_find_freq_exact(dev, freq, false);
+	if (IS_ERR(opp)) {
+		ret = PTR_ERR(opp);
+		goto put_table;
+	}
+
+	mutex_lock(&opp_table->lock);
+
+	/* update only if the opp is disabled */
+	if (opp->available) {
+		ret = -EBUSY;
+		goto unlock;
+	}
+
+	tol = u_volt * opp_table->voltage_tolerance_v1 / 100;
+	opp->supplies[0].u_volt_min = u_volt - tol;
+	opp->supplies[0].u_volt = u_volt;
+	opp->supplies[0].u_volt_min = u_volt + tol;
+
+unlock:
+	mutex_unlock(&opp_table->lock);
+	dev_pm_opp_put(opp);
+put_table:
+	dev_pm_opp_put_opp_table(opp_table);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_update_voltage);
+
 /**
  * dev_pm_opp_register_notifier() - Register OPP notifier for the device
  * @dev:	Device for which notifier needs to be registered
diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h
index 62c88898bae46..b26d492cbd635 100644
--- a/include/linux/pm_opp.h
+++ b/include/linux/pm_opp.h
@@ -132,6 +132,9 @@  int dev_pm_opp_enable(struct device *dev, unsigned long freq);
 
 int dev_pm_opp_disable(struct device *dev, unsigned long freq);
 
+int dev_pm_opp_update_voltage(struct device *dev, unsigned long freq,
+			      unsigned long u_volt);
+
 int dev_pm_opp_register_notifier(struct device *dev, struct notifier_block *nb);
 int dev_pm_opp_unregister_notifier(struct device *dev, struct notifier_block *nb);
 
@@ -311,6 +314,13 @@  static inline int dev_pm_opp_disable(struct device *dev, unsigned long freq)
 	return 0;
 }
 
+static inline int dev_pm_opp_update_voltage(struct device *dev,
+					    unsigned long freq,
+					    unsigned long u_volt)
+{
+	return 0;
+}
+
 static inline int dev_pm_opp_register_notifier(struct device *dev, struct notifier_block *nb)
 {
 	return -ENOTSUPP;