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@xxxxxxxxx>
> ---
> 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)
