Re: [External] : RE: Re : [PATCH v5 3/5] thermal: renesas: rzg3e: Add thermal driver for the Renesas RZ/G3E SoC

[ALOK TIWARI]

Hi John,

On 03-04-2025 00:52, John Madieu wrote:
> Hi Alok,
>
> > -----Original Message-----
> > From: ALOK TIWARI <alok.a.tiwari@xxxxxxxxxx>
> > Sent: Tuesday, April 1, 2025 8:24 PM
> > To: John Madieu <john.madieu.xa@xxxxxxxxxxxxxx>; geert+renesas@xxxxxxxxx;
> > conor+dt@xxxxxxxxxx; krzk+dt@xxxxxxxxxx; robh@xxxxxxxxxx;
> > rafael@xxxxxxxxxx; daniel.lezcano@xxxxxxxxxx
> > Subject: Re : [PATCH v5 3/5] thermal: renesas: rzg3e: Add thermal driver
> > for the Renesas RZ/G3E SoC
> >
> > Hi John,
> >
> > Thanks for your reply.
> >
> > On 01-04-2025 17:35, John Madieu wrote:
> > > Hi Alok,
> > >
> > > Thanks for your feedback.
> > >
> > > > -----Original Message-----
> > > > From: ALOK TIWARI <alok.a.tiwari@xxxxxxxxxx>
> > > > Sent: Monday, March 31, 2025 8:11 PM
> > > > To: John Madieu <john.madieu.xa@xxxxxxxxxxxxxx>;
> > > > geert+renesas@xxxxxxxxx;
> > > > conor+dt@xxxxxxxxxx; krzk+dt@xxxxxxxxxx; robh@xxxxxxxxxx;
> > > > rafael@xxxxxxxxxx; daniel.lezcano@xxxxxxxxxx
> > > > Subject: Re : [PATCH v5 3/5] thermal: renesas: rzg3e: Add thermal
> > > > driver for the Renesas RZ/G3E SoC
> > > >
> > > >
> > > >
> > > > On 31-03-2025 03:19, John Madieu wrote:
> > > > > The RZ/G3E SoC integrates a Temperature Sensor Unit (TSU) block
> >
> > > > > +static int rzg3e_thermal_change_mode(struct thermal_zone_device *tz,
> > > > > +				     enum thermal_device_mode mode) {
> > > > > +	struct rzg3e_thermal_priv *priv = thermal_zone_device_priv(tz);
> > > > > +
> > > > > +	if (mode == THERMAL_DEVICE_DISABLED)
> > > > > +		rzg3e_thermal_hw_disable(priv);
> > > > > +	else
> > > > > +		rzg3e_thermal_hw_enable(priv);
> > > > > +
> > > > > +	priv->mode = mode;
> > > > > +	return 0;
> > > > > +}
> > > > > +
> > > > always return 0 here ? what, if (!priv) return -EINVAL; ?
> > >
> > > priv cannot be NULL here, guaranteed from probe().
> > > Returning 0 here is expected by the thermal framework to notify ops
> > > success.
> >
> > I agreed. priv cannot be NULL.
> > It appears that return 0 is deliberate in this case. can we add Meaningful
> > comment which help to code readability.
>
> This is a standard tzd ops, which expects 0 to be returned
> for disabling/enabling success. This is how it's implemented
> in every Thermal driver I've gone through in the -next tree.
>
> > not sure if user call ioctl(fd, THERMAL_IOC_SET_MODE, 2) and it returns
> > 0 with thermal enable.
> > that create possibility to thermal_core call thermal_notify_tz_disable if
> > any case
> Am I missing something ?

That's fine. it is not supporting ioctl.
usually thermal core driver do check if(mode == THERMAL_DEVICE_ENABLED) 
condition, else part is by-default.
as it is supporting only enable/disable case from 
/sys/class/thermal/thermal_zone0/mode. it does not create any issue.
LGTM.

> > > > > +static const struct thermal_zone_device_ops rzg3e_tz_ops = {
> > > > > +	.get_temp = rzg3e_thermal_get_temp,
> > > > > +	.set_trips = rzg3e_thermal_set_trips,
> > > > > +	.change_mode = rzg3e_thermal_change_mode, };
> > > > other renesas driver defined as rzg2l_tz_of_ops, can be used similar
> > > > one rzg3e_tz_of_ops for consistency!
> > >
> > > Thanks for pointing it out. Makes sense. Will double check and update
> > > accordingly.
> > >
> > > > > +
> > > > > +static int rzg3e_thermal_probe(struct platform_device *pdev) {
> > > > > +	struct device *dev = &pdev->dev;
> > > > > +	struct rzg3e_thermal_priv *priv;
> > > > > +	struct reset_control *rstc;
> Regards,
> John