Re: [PATCH v5] hwmon: (pmbus/core): Implement regulator get_status

[Naresh Solanki]

On 24-11-2022 07:48 pm, Guenter Roeck wrote:
> On 11/24/22 00:34, Naresh Solanki wrote:
> > From: Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx>
> >
> > Add get_status for pmbus_regulator_ops.
> >
> > ---
> > Changes:
> > - use lock throughout the function
> > - Avoid line continuation upto 100 column
> > - Optimize use of & and | operator
> > - Check for VOUT, IOUT, TEMPERATURE bit in status word before checking
> >    respective status register for fault.
> > - Report regulator current status.
> > - Utilize get_error_flag to check for regulator errors.
> > - Check for return value of function get_error_flag
> >
> > Signed-off-by: Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx>
> > Signed-off-by: Naresh Solanki <Naresh.Solanki@xxxxxxxxxxxxx>
> > ---
> >   drivers/hwmon/pmbus/pmbus_core.c | 44 ++++++++++++++++++++++++++++++++
> >   1 file changed, 44 insertions(+)
> >
> > diff --git a/drivers/hwmon/pmbus/pmbus_core.c 
> > b/drivers/hwmon/pmbus/pmbus_core.c
> > index 20ca26e19db7..0b13214c662f 100644
> > --- a/drivers/hwmon/pmbus/pmbus_core.c
> > +++ b/drivers/hwmon/pmbus/pmbus_core.c
> > @@ -2855,6 +2855,49 @@ static int 
> > pmbus_regulator_get_error_flags(struct regulator_dev *rdev, unsigned
> >       return 0;
> >   }
> > +static int pmbus_regulator_get_status(struct regulator_dev *rdev)
> > +{
> > +    struct device *dev = rdev_get_dev(rdev);
> > +    struct i2c_client *client = to_i2c_client(dev->parent);
> > +    struct pmbus_data *data = i2c_get_clientdata(client);
> > +    u8 page = rdev_get_id(rdev);
> > +    int status, ret;
> > +
> > +    mutex_lock(&data->update_lock);
> > +    status = pmbus_get_status(client, page, PMBUS_STATUS_WORD);
> > +    if (status < 0) {
> > +        ret = status;
> > +        goto unlock;
> > +    }
> > +
> > +    if (status & PB_STATUS_OFF) {
> > +        ret = REGULATOR_STATUS_OFF;
> > +        goto unlock;
> > +    }
> > +
> > +    /* If regulator is ON & reports power good then return ON */
> > +    if (!(status & PB_STATUS_POWER_GOOD_N)) {
> > +        ret = REGULATOR_STATUS_ON;
> > +        goto unlock;
> > +    }
> > +
> > +    if (rdev->desc->ops->get_error_flags) {
>
> Looking into this again, why is this check necessary ? Isn't this
> the regulator_ops from below ? Also, why not just call
> pmbus_regulator_get_error_flags() directly ?
Yes. Felt that to be the right way.
Will update to do pmbus_regulator_get)error_flags directly
> > +        ret = rdev->desc->ops->get_error_flags(rdev, &status);
> > +        if (ret)
> > +            goto unlock;
> > +
> > +        if (status & (REGULATOR_ERROR_UNDER_VOLTAGE | 
> > REGULATOR_ERROR_OVER_CURRENT |
> > +           REGULATOR_ERROR_REGULATION_OUT | REGULATOR_ERROR_FAIL |
> > +           REGULATOR_ERROR_OVER_TEMP))
> > +            ret = REGULATOR_STATUS_ERROR;
>
> If the condition above is false, the return value will be 0, or
> REGULATOR_STATUS_OFF. Is that intentional ?
No. It should be REGULATOR_ERR_UNDEFINED. will fix in next revision.
> > +    } else
> > +        ret = REGULATOR_STATUS_UNDEFINED;
> > +
>
> CHECK: braces {} should be used on all arms of this statement
> #72: FILE: drivers/hwmon/pmbus/pmbus_core.c:2884:
> +    if (rdev->desc->ops->get_error_flags) {
> [...]
> +    } else
>
> Guenter
>
> > +unlock:
> > +    mutex_unlock(&data->update_lock);
> > +    return ret;
> > +}
> > +
> >   static int pmbus_regulator_get_low_margin(struct i2c_client *client, 
> > int page)
> >   {
> >       struct pmbus_data *data = i2c_get_clientdata(client);
> > @@ -2995,6 +3038,7 @@ const struct regulator_ops pmbus_regulator_ops = {
> >       .disable = pmbus_regulator_disable,
> >       .is_enabled = pmbus_regulator_is_enabled,
> >       .get_error_flags = pmbus_regulator_get_error_flags,
> > +    .get_status = pmbus_regulator_get_status,
> >       .get_voltage = pmbus_regulator_get_voltage,
> >       .set_voltage = pmbus_regulator_set_voltage,
> >       .list_voltage = pmbus_regulator_list_voltage,
> >
> > base-commit: 2c71b3246ec3246522e8cb7c8191dc7a5d62cc70

Regards,
Naresh