On Sat, Sep 29, 2018 at 08:33:46AM -0700, Guenter Roeck wrote:
> On Fri, Sep 28, 2018 at 02:49:21PM -0700, Nicolin Chen wrote:
> > Depending on the hardware design, an INA3221 chip might lose
> > its power during system suspend/resume. So this patch adds
> > a pair of suspend and resume functions to cache the register
> > values including config register value and limit settings.
> >
> > Signed-off-by: Nicolin Chen <nicoleotsuka@xxxxxxxxx>
> > ---
> > drivers/hwmon/ina3221.c | 54 +++++++++++++++++++++++++++++++++++++++++
> > 1 file changed, 54 insertions(+)
> >
> > diff --git a/drivers/hwmon/ina3221.c b/drivers/hwmon/ina3221.c
> > index cfe65ff01051..26f66f728b27 100644
> > --- a/drivers/hwmon/ina3221.c
> > +++ b/drivers/hwmon/ina3221.c
> > @@ -91,11 +91,13 @@ static const unsigned int register_channel[] = {
> > * @regmap: Register map of the device
> > * @fields: Register fields of the device
> > * @shunt_resistors: Array of resistor values per channel
> > + * @reg_config: Register value of INA3221_CONFIG
> > */
> > struct ina3221_data {
> > struct regmap *regmap;
> > struct regmap_field *fields[F_MAX_FIELDS];
> > int shunt_resistors[INA3221_NUM_CHANNELS];
> > + u32 reg_config;
> > };
> >
> > static int ina3221_read_value(struct ina3221_data *ina, unsigned int reg,
> > @@ -415,8 +417,59 @@ static int ina3221_probe(struct i2c_client *client,
> > return PTR_ERR(hwmon_dev);
> > }
> >
> > + dev_set_drvdata(dev, ina);
> > +
> > + return 0;
> > +}
> > +
> > +#ifdef CONFIG_PM
> > +static int ina3221_suspend(struct device *dev)
> > +{
> > + struct ina3221_data *ina = dev_get_drvdata(dev);
> > + int ret;
> > +
> > + /* Save config register value and enable cache-only */
> > + ret = regmap_read(ina->regmap, INA3221_CONFIG, &ina->reg_config);
> > + if (ret)
> > + return ret;
> > +
>
> Would it make sense to explicitly disable all channels here ?
For power saving? I could add it to v2.
Thanks
Nicolin
