Re: [PATCH v2 4/4] hwmon: (pmbus/core): Notify hwmon events

[Naresh Solanki <naresh.solanki@xxxxxxxxxxxxx>]

Hi,

On 11-02-2023 09:16 pm, Guenter Roeck wrote:
> On Tue, Feb 07, 2023 at 01:02:41PM +0100, Naresh Solanki wrote:
> > From: Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx>
> >
> > Notify hwmon events using the pmbus irq handler.
> >
> > Signed-off-by: Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx>
> > Signed-off-by: Naresh Solanki <Naresh.Solanki@xxxxxxxxxxxxx>
> > ...
> > Changes in V2
> > - Remove __maybe_unsed attribute as its not needed.
> > ---
> >   drivers/hwmon/pmbus/pmbus_core.c | 48 ++++++++++++++++++++++++++++----
> >   1 file changed, 43 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
> > index d5403baad60a..f6778a9c7126 100644
> > --- a/drivers/hwmon/pmbus/pmbus_core.c
> > +++ b/drivers/hwmon/pmbus/pmbus_core.c
> > @@ -2735,8 +2735,36 @@ static const struct pmbus_status_category __maybe_unused pmbus_status_flag_map[]
> >   	},
> >   };
> >   
> > +#define to_dev_attr(_dev_attr) \
> > +	container_of(_dev_attr, struct device_attribute, attr)
> > +
> > +static void pmbus_notify(struct pmbus_data *data, int page, int reg, int flags)
> > +{
> > +	int i;
> > +
> > +	for (i = 0; i < data->num_attributes; i++) {
> > +		struct device_attribute *da = to_dev_attr(data->group.attrs[i]);
> > +		struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
> > +		int index = attr->index;
> > +		u16 smask = pb_index_to_mask(index);
> > +		u8 spage = pb_index_to_page(index);
> > +		u16 sreg = pb_index_to_reg(index);
> > +
> > +		if (reg == sreg && page == spage && (smask & flags)) {
> > +			dev_dbg(data->dev, "sysfs notify: %s", da->attr.name);
> > +			sysfs_notify(&data->dev->kobj, NULL, da->attr.name);
> > +			kobject_uevent(&data->dev->kobj, KOBJ_CHANGE);
> > +			flags &= ~smask;
> > +		}
> > +
> > +		if (!flags)
> > +			break;
> > +	}
> > +}
> > +
> > +static int pmbus_get_flags(struct pmbus_data *data, u8 page, unsigned int *flags,
> > +			   bool notify)
> >   
> > -static int __maybe_unused pmbus_get_flags(struct pmbus_data *data, u8 page, unsigned int *flags)
> >   {
> >   	int i, status, ret;
> >   	const struct pmbus_status_category *cat;
> > @@ -2764,6 +2792,10 @@ static int __maybe_unused pmbus_get_flags(struct pmbus_data *data, u8 page, unsi
> >   			if (status & bit->pflag)
> >   				*flags |= bit->rflag;
> >   		}
> > +
> > +		if (notify && status)
> > +			pmbus_notify(data, page, cat->reg, status);
> > +
> >   	}
> >   
> >   	/*
> > @@ -2866,7 +2898,7 @@ static int pmbus_regulator_get_error_flags(struct regulator_dev *rdev, unsigned
> >   	struct i2c_client *client = to_i2c_client(dev->parent);
> >   	struct pmbus_data *data = i2c_get_clientdata(client);
> >   
> > -	return pmbus_get_flags(data, rdev_get_id(rdev), flags);
> > +	return pmbus_get_flags(data, rdev_get_id(rdev), flags, false);
> >   }
> >   
> >   static int pmbus_regulator_get_status(struct regulator_dev *rdev)
> > @@ -3108,10 +3140,14 @@ static irqreturn_t pmbus_fault_handler(int irq, void *pdata)
> >   {
> >   	struct pmbus_data *data = pdata;
> >   	struct i2c_client *client = to_i2c_client(data->dev);
> > -	int i, status;
> > +	int i, status, ret;
> >   
> > -	mutex_lock(&data->update_lock);
> >   	for (i = 0; i < data->info->pages; i++) {
> > +		ret = pmbus_get_flags(data, i, &status, true);
> > +		if (ret)
> > +			return ret;
> > +
> > +		mutex_lock(&data->update_lock);
>
> You should introduce a locked version of pmbus_get_flags() and call
> that function, and keep the existing locking in place.
I'm not sure if you meant to have pmbus_get_flags that wont use lock?

> >   		status = pmbus_read_status_word(client, i);
> >   		if (status < 0) {
> >   			mutex_unlock(&data->update_lock);
> > @@ -3120,8 +3156,10 @@ static irqreturn_t pmbus_fault_handler(int irq, void *pdata)
> >   
> >   		if (status & ~(PB_STATUS_OFF | PB_STATUS_BUSY | PB_STATUS_POWER_GOOD_N))
> >   			pmbus_clear_fault_page(client, i);
> > +
> > +		mutex_unlock(&data->update_lock);
> >   	}
> > -	mutex_unlock(&data->update_lock);
> > +
>
> This would add a second empty line (not that it matters because the code
> should not change the locking in the first place).
Will remove the new line
> >   
> >   	return IRQ_HANDLED;
> >   }