[PATCH v2 0/2] hwmon (ina3221) Add single-shot mode support

[PATCH v2 0/2] hwmon (ina3221) Add single-shot mode support

[Nicolin Chen]

By default, ina3221, as a hardware monitor, continuously measures
the inputs and generates corresponding data. However, for battery
powered devices, this mode might be power consuming.

This series of patches add a feature of changing default operating
mode to its single-shot mode via DT.

Changelog
v1->v2:
 * Cleaned-up PATCH-2

Nicolin Chen (2):
  dt-bindings: hwmon: ina3221: Add ti,single-shot property
  hwmon: (ina3221) Implement ti,single-shot DT property

 .../devicetree/bindings/hwmon/ina3221.txt     | 10 ++++++++++
 drivers/hwmon/ina3221.c                       | 20 +++++++++++++++++++
 2 files changed, 30 insertions(+)

-- 
2.17.1

[PATCH v2 1/2] dt-bindings: hwmon: ina3221: Add ti,single-shot property

[Nicolin Chen]

By default, ina3221, as a hardware monitor, continuously measures
the inputs and generates corresponding data. However, for battery
powered devices, this mode might be power consuming.

This patch adds a "ti,single-shot" property to allow changing the
default continuous mode to single-shot operating mode.

Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
---
 Documentation/devicetree/bindings/hwmon/ina3221.txt | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/Documentation/devicetree/bindings/hwmon/ina3221.txt b/Documentation/devicetree/bindings/hwmon/ina3221.txt
index a7b25caa2b8e..fa63b6171407 100644
--- a/Documentation/devicetree/bindings/hwmon/ina3221.txt
+++ b/Documentation/devicetree/bindings/hwmon/ina3221.txt
@@ -6,6 +6,16 @@ Texas Instruments INA3221 Device Tree Bindings
   - reg: I2C address
 
   Optional properties:
+  - ti,single-shot: This chip has two power modes: single-shot (chip takes one
+                    measurement and then shuts itself down) and continuous (
+                    chip takes continuous measurements). The continuous mode is
+                    more reliable and suitable for hardware monitor type device,
+                    but the single-shot mode is more power-friendly and useful
+                    for battery-powered device which cares power consumptions
+                    while still needs some measurements occasionally.
+                    If this property is present, the single-shot mode will be
+                    used, instead of the default continuous one for monitoring.
+
   = The node contains optional child nodes for three channels =
   = Each child node describes the information of input source =
 
-- 
2.17.1

[PATCH v2 2/2] hwmon: (ina3221) Implement ti,single-shot DT property

[Nicolin Chen]

By default, ina3221, as a hardware monitor, continuously measures
the inputs and generates corresponding data. However, for battery
powered devices, this mode might be power consuming.

The DT binding doc is updated with a new boolean type property to
allow changing the default operating mode from consuming mode to
single-shot mode, which will measure input on demand and then shut
down to save power.

So this patch implements the DT property accordingly.

Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
---
Changelog
v1->v2:
 * Replaced the useless mode defines with a boolean variable.

 drivers/hwmon/ina3221.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/drivers/hwmon/ina3221.c b/drivers/hwmon/ina3221.c
index e90ccac8bebb..4258a6ebe195 100644
--- a/drivers/hwmon/ina3221.c
+++ b/drivers/hwmon/ina3221.c
@@ -111,6 +111,7 @@ struct ina3221_input {
  * @inputs: Array of channel input source specific structures
  * @lock: mutex lock to serialize sysfs attribute accesses
  * @reg_config: Register value of INA3221_CONFIG
+ * @single_shot: running in single-shot operating mode
  */
 struct ina3221_data {
 	struct device *pm_dev;
@@ -119,6 +120,8 @@ struct ina3221_data {
 	struct ina3221_input inputs[INA3221_NUM_CHANNELS];
 	struct mutex lock;
 	u32 reg_config;
+
+	bool single_shot;
 };
 
 static inline bool ina3221_is_enabled(struct ina3221_data *ina, int channel)
@@ -188,6 +191,11 @@ static int ina3221_read_in(struct device *dev, u32 attr, int channel, long *val)
 		if (!ina3221_is_enabled(ina, channel))
 			return -ENODATA;
 
+		/* Write CONFIG register to trigger a single-shot measurement */
+		if (ina->single_shot)
+			regmap_write(ina->regmap, INA3221_CONFIG,
+				     ina->reg_config);
+
 		ret = ina3221_wait_for_data(ina);
 		if (ret)
 			return ret;
@@ -232,6 +240,11 @@ static int ina3221_read_curr(struct device *dev, u32 attr,
 		if (!ina3221_is_enabled(ina, channel))
 			return -ENODATA;
 
+		/* Write CONFIG register to trigger a single-shot measurement */
+		if (ina->single_shot)
+			regmap_write(ina->regmap, INA3221_CONFIG,
+				     ina->reg_config);
+
 		ret = ina3221_wait_for_data(ina);
 		if (ret)
 			return ret;
@@ -617,6 +630,9 @@ static int ina3221_probe_from_dt(struct device *dev, struct ina3221_data *ina)
 	if (!np)
 		return 0;
 
+	if (of_property_read_bool(np, "ti,single-shot"))
+		ina->single_shot = true;
+
 	for_each_child_of_node(np, child) {
 		ret = ina3221_probe_child_from_dt(dev, child, ina);
 		if (ret)
@@ -666,6 +682,10 @@ static int ina3221_probe(struct i2c_client *client,
 	/* The driver will be reset, so use reset value */
 	ina->reg_config = INA3221_CONFIG_DEFAULT;
 
+	/* Clear continuous bit to use single-shot mode */
+	if (ina->single_shot)
+		ina->reg_config &= ~INA3221_CONFIG_MODE_CONTINUOUS;
+
 	/* Disable channels if their inputs are disconnected */
 	for (i = 0; i < INA3221_NUM_CHANNELS; i++) {
 		if (ina->inputs[i].disconnected)
-- 
2.17.1

[PATCH v2 2/2] hwmon: (ina3221) Implement ti,single-shot DT property

[Nicolin Chen]

By default, ina3221, as a hardware monitor, continuously measures
the inputs and generates corresponding data. However, for battery
powered devices, this mode might be power consuming.

The DT binding doc is updated with a new boolean type property to
allow changing the default operating mode from consuming mode to
single-shot mode, which will measure input on demand and then shut
down to save power.

So this patch implements the DT property accordingly.

Signed-off-by: Nicolin Chen <nicoleots...@gmail.com>
---
Changelog
v1->v2:
 * Replaced the useless mode defines with a boolean variable.

 drivers/hwmon/ina3221.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/drivers/hwmon/ina3221.c b/drivers/hwmon/ina3221.c
index e90ccac8bebb..4258a6ebe195 100644
--- a/drivers/hwmon/ina3221.c
+++ b/drivers/hwmon/ina3221.c
@@ -111,6 +111,7 @@ struct ina3221_input {
  * @inputs: Array of channel input source specific structures
  * @lock: mutex lock to serialize sysfs attribute accesses
  * @reg_config: Register value of INA3221_CONFIG
+ * @single_shot: running in single-shot operating mode
  */
 struct ina3221_data {
        struct device *pm_dev;
@@ -119,6 +120,8 @@ struct ina3221_data {
        struct ina3221_input inputs[INA3221_NUM_CHANNELS];
        struct mutex lock;
        u32 reg_config;
+
+       bool single_shot;
 };
 
 static inline bool ina3221_is_enabled(struct ina3221_data *ina, int channel)
@@ -188,6 +191,11 @@ static int ina3221_read_in(struct device *dev, u32 attr, 
int channel, long *val)
                if (!ina3221_is_enabled(ina, channel))
                        return -ENODATA;
 
+               /* Write CONFIG register to trigger a single-shot measurement */
+               if (ina->single_shot)
+                       regmap_write(ina->regmap, INA3221_CONFIG,
+                                    ina->reg_config);
+
                ret = ina3221_wait_for_data(ina);
                if (ret)
                        return ret;
@@ -232,6 +240,11 @@ static int ina3221_read_curr(struct device *dev, u32 attr,
                if (!ina3221_is_enabled(ina, channel))
                        return -ENODATA;
 
+               /* Write CONFIG register to trigger a single-shot measurement */
+               if (ina->single_shot)
+                       regmap_write(ina->regmap, INA3221_CONFIG,
+                                    ina->reg_config);
+
                ret = ina3221_wait_for_data(ina);
                if (ret)
                        return ret;
@@ -617,6 +630,9 @@ static int ina3221_probe_from_dt(struct device *dev, struct 
ina3221_data *ina)
        if (!np)
                return 0;
 
+       if (of_property_read_bool(np, "ti,single-shot"))
+               ina->single_shot = true;
+
        for_each_child_of_node(np, child) {
                ret = ina3221_probe_child_from_dt(dev, child, ina);
                if (ret)
@@ -666,6 +682,10 @@ static int ina3221_probe(struct i2c_client *client,
        /* The driver will be reset, so use reset value */
        ina->reg_config = INA3221_CONFIG_DEFAULT;
 
+       /* Clear continuous bit to use single-shot mode */
+       if (ina->single_shot)
+               ina->reg_config &= ~INA3221_CONFIG_MODE_CONTINUOUS;
+
        /* Disable channels if their inputs are disconnected */
        for (i = 0; i < INA3221_NUM_CHANNELS; i++) {
                if (ina->inputs[i].disconnected)
-- 
2.17.1

[PATCH v2 1/2] dt-bindings: hwmon: ina3221: Add ti,single-shot property

[Nicolin Chen]

By default, ina3221, as a hardware monitor, continuously measures
the inputs and generates corresponding data. However, for battery
powered devices, this mode might be power consuming.

This patch adds a "ti,single-shot" property to allow changing the
default continuous mode to single-shot operating mode.

Signed-off-by: Nicolin Chen <nicoleots...@gmail.com>
---
 Documentation/devicetree/bindings/hwmon/ina3221.txt | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/Documentation/devicetree/bindings/hwmon/ina3221.txt 
b/Documentation/devicetree/bindings/hwmon/ina3221.txt
index a7b25caa2b8e..fa63b6171407 100644
--- a/Documentation/devicetree/bindings/hwmon/ina3221.txt
+++ b/Documentation/devicetree/bindings/hwmon/ina3221.txt
@@ -6,6 +6,16 @@ Texas Instruments INA3221 Device Tree Bindings
   - reg: I2C address
 
   Optional properties:
+  - ti,single-shot: This chip has two power modes: single-shot (chip takes one
+                    measurement and then shuts itself down) and continuous (
+                    chip takes continuous measurements). The continuous mode is
+                    more reliable and suitable for hardware monitor type 
device,
+                    but the single-shot mode is more power-friendly and useful
+                    for battery-powered device which cares power consumptions
+                    while still needs some measurements occasionally.
+                    If this property is present, the single-shot mode will be
+                    used, instead of the default continuous one for monitoring.
+
   = The node contains optional child nodes for three channels =
   = Each child node describes the information of input source =
 
-- 
2.17.1

[PATCH v2 0/2] hwmon (ina3221) Add single-shot mode support

[Nicolin Chen]

By default, ina3221, as a hardware monitor, continuously measures
the inputs and generates corresponding data. However, for battery
powered devices, this mode might be power consuming.

This series of patches add a feature of changing default operating
mode to its single-shot mode via DT.

Changelog
v1->v2:
 * Cleaned-up PATCH-2

Nicolin Chen (2):
  dt-bindings: hwmon: ina3221: Add ti,single-shot property
  hwmon: (ina3221) Implement ti,single-shot DT property

 .../devicetree/bindings/hwmon/ina3221.txt     | 10 ++++++++++
 drivers/hwmon/ina3221.c                       | 20 +++++++++++++++++++
 2 files changed, 30 insertions(+)

-- 
2.17.1

Re: [PATCH v2 2/2] hwmon: (ina3221) Implement ti,single-shot DT property

[Guenter Roeck]

On Fri, Jan 04, 2019 at 07:06:36PM -0800, Nicolin Chen wrote:
> By default, ina3221, as a hardware monitor, continuously measures
> the inputs and generates corresponding data. However, for battery
> powered devices, this mode might be power consuming.
> 
> The DT binding doc is updated with a new boolean type property to
> allow changing the default operating mode from consuming mode to
> single-shot mode, which will measure input on demand and then shut
> down to save power.
> 
> So this patch implements the DT property accordingly.
> 
> Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
> ---
> Changelog
> v1->v2:
>  * Replaced the useless mode defines with a boolean variable.
> 
>  drivers/hwmon/ina3221.c | 20 ++++++++++++++++++++
>  1 file changed, 20 insertions(+)
> 
> diff --git a/drivers/hwmon/ina3221.c b/drivers/hwmon/ina3221.c
> index e90ccac8bebb..4258a6ebe195 100644
> --- a/drivers/hwmon/ina3221.c
> +++ b/drivers/hwmon/ina3221.c
> @@ -111,6 +111,7 @@ struct ina3221_input {
>   * @inputs: Array of channel input source specific structures
>   * @lock: mutex lock to serialize sysfs attribute accesses
>   * @reg_config: Register value of INA3221_CONFIG
> + * @single_shot: running in single-shot operating mode
>   */
>  struct ina3221_data {
>  	struct device *pm_dev;
> @@ -119,6 +120,8 @@ struct ina3221_data {
>  	struct ina3221_input inputs[INA3221_NUM_CHANNELS];
>  	struct mutex lock;
>  	u32 reg_config;
> +
> +	bool single_shot;
>  };
>  
>  static inline bool ina3221_is_enabled(struct ina3221_data *ina, int channel)
> @@ -188,6 +191,11 @@ static int ina3221_read_in(struct device *dev, u32 attr, int channel, long *val)
>  		if (!ina3221_is_enabled(ina, channel))
>  			return -ENODATA;
>  
> +		/* Write CONFIG register to trigger a single-shot measurement */
> +		if (ina->single_shot)
> +			regmap_write(ina->regmap, INA3221_CONFIG,
> +				     ina->reg_config);
> +
>  		ret = ina3221_wait_for_data(ina);
>  		if (ret)
>  			return ret;
> @@ -232,6 +240,11 @@ static int ina3221_read_curr(struct device *dev, u32 attr,
>  		if (!ina3221_is_enabled(ina, channel))
>  			return -ENODATA;
>  
> +		/* Write CONFIG register to trigger a single-shot measurement */
> +		if (ina->single_shot)
> +			regmap_write(ina->regmap, INA3221_CONFIG,
> +				     ina->reg_config);
> +
>  		ret = ina3221_wait_for_data(ina);
>  		if (ret)
>  			return ret;
> @@ -617,6 +630,9 @@ static int ina3221_probe_from_dt(struct device *dev, struct ina3221_data *ina)
>  	if (!np)
>  		return 0;
>  
> +	if (of_property_read_bool(np, "ti,single-shot"))
> +		ina->single_shot = true;
> +
	ina->single_shot = of_property_read_bool(np, "ti,single-shot");

No need to resend right now; let's wait for feedback from Rob.

Guenter

>  	for_each_child_of_node(np, child) {
>  		ret = ina3221_probe_child_from_dt(dev, child, ina);
>  		if (ret)
> @@ -666,6 +682,10 @@ static int ina3221_probe(struct i2c_client *client,
>  	/* The driver will be reset, so use reset value */
>  	ina->reg_config = INA3221_CONFIG_DEFAULT;
>  
> +	/* Clear continuous bit to use single-shot mode */
> +	if (ina->single_shot)
> +		ina->reg_config &= ~INA3221_CONFIG_MODE_CONTINUOUS;
> +
>  	/* Disable channels if their inputs are disconnected */
>  	for (i = 0; i < INA3221_NUM_CHANNELS; i++) {
>  		if (ina->inputs[i].disconnected)

Re: [PATCH v2 1/2] dt-bindings: hwmon: ina3221: Add ti,single-shot property

[Rob Herring]

On Fri,  4 Jan 2019 19:06:35 -0800, Nicolin Chen wrote:
> By default, ina3221, as a hardware monitor, continuously measures
> the inputs and generates corresponding data. However, for battery
> powered devices, this mode might be power consuming.
> 
> This patch adds a "ti,single-shot" property to allow changing the
> default continuous mode to single-shot operating mode.
> 
> Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
> ---
>  Documentation/devicetree/bindings/hwmon/ina3221.txt | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 

Reviewed-by: Rob Herring <robh@kernel.org>

Re: [PATCH v2 2/2] hwmon: (ina3221) Implement ti,single-shot DT property

[Nicolin Chen]

On Mon, Jan 07, 2019 at 11:35:55AM -0800, Guenter Roeck wrote:

> > +	if (of_property_read_bool(np, "ti,single-shot"))
> > +		ina->single_shot = true;
> > +
> 	ina->single_shot = of_property_read_bool(np, "ti,single-shot");
> 
> No need to resend right now; let's wait for feedback from Rob.

Looks like Rob has acked. Is this resend version fine for review?

Thank you
Nicolin

Re: [PATCH v2 2/2] hwmon: (ina3221) Implement ti,single-shot DT property

[Guenter Roeck]

On Thu, Jan 17, 2019 at 02:30:13PM -0800, Nicolin Chen wrote:
> On Mon, Jan 07, 2019 at 11:35:55AM -0800, Guenter Roeck wrote:
> 
> > > +	if (of_property_read_bool(np, "ti,single-shot"))
> > > +		ina->single_shot = true;
> > > +
> > 	ina->single_shot = of_property_read_bool(np, "ti,single-shot");
> > 
> > No need to resend right now; let's wait for feedback from Rob.
> 
> Looks like Rob has acked. Is this resend version fine for review?
> 
"Right now" was supposed to mean that you should wait for Rob's
feedback before sending v3 with the feedback above applied.
Did you send that version ? I don't see it in patchwork, nor
in my inbox.

Thanks,
Guenter

Re: [PATCH v2 2/2] hwmon: (ina3221) Implement ti,single-shot DT property

[Nicolin Chen]

On Thu, Jan 17, 2019 at 02:58:42PM -0800, Guenter Roeck wrote:

> "Right now" was supposed to mean that you should wait for Rob's
> feedback before sending v3 with the feedback above applied.
> Did you send that version ? I don't see it in patchwork, nor
> in my inbox.

Oh, sorry. Will resend it.

Thanks for the reply.