Re: [bug report] thermal: Add cooling device's statistics in sysfs

[Dan Carpenter <dan.carpenter@oracle.com>]

On Mon, Oct 17, 2022 at 03:08:29PM +0530, Viresh Kumar wrote:
> On 14-10-22, 17:30, Dan Carpenter wrote:
> > (There are some drivers which might cap new_state.  I only looked at
> > tc654_set_cur_state() and it doesn't cap the value.  It's always going
> > to be safer to do the bounds checking in a central place).
> 
> I agree that it is better to do it at central place.
> 
> But, tc654_set_cur_state() seems to be doing it just fine:
> 
> static int tc654_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state)
> {
> 	struct tc654_data *data = tc654_update_client(cdev->devdata);
> 
> 	if (IS_ERR(data))
> 		return PTR_ERR(data);
> 
> 	return _set_pwm(data, clamp_val(state, 0, TC654_MAX_COOLING_STATE));

Ideally it would return -EINVAL for invalid state values instead of
clamping it to a valid range.

I feel like -EINVAL is generally a better API.  But also if we're
relying it to check and return an error code then obviously that's not
what it does.

regards,
dan carpenter