[PATCH 26/38] iio: pressure-core: st: Clean-up probe() function

Jonathan Cameron
2013-09-14T17:21:13Z

On 09/11/13 08:19, Lee Jones wrote:
>>> err = st_sensors_init_sensor(indio_dev, plat_data);
>>> if (err < 0)
>>> - goto st_press_common_probe_error;
>>> + return err;
>>>
>>> - if (pdata->get_irq_data_ready(indio_dev) > 0) {
>>> + if (irq > 0) {
>>> err = st_press_allocate_ring(indio_dev);
>>> if (err < 0)
>>> - goto st_press_common_probe_error;
>>> + return err;
>>>
>>> err = st_sensors_allocate_trigger(indio_dev,
>>> - ST_PRESS_TRIGGER_OPS);
>>> + ST_PRESS_TRIGGER_OPS);
>>> if (err < 0)
>>> goto st_press_probe_trigger_error;
>>> }
>>>
>>> err = iio_device_register(indio_dev);
>>> - if (err)
>>
>> This bit of handling is confusing. I would much rather see the if IRQ at the goto. Here the first thought is why is it not an error if there is no IRQ!
>
> I certainly see your point. But surely anyone would see after a second
> or two that we're returning err and not 0 in this case, so the error
> would still be returned, we're not ignoring it. Adding this extra
> comparison saves several lines of code.
>
> If you think it's 'too' confusing, I'll revert the change.
>
> Or perhaps a comment:
>
> /* Only deallocate_[trigger|ring] if they were allocated. */
> or
> /* Only deallocate_[trigger|ring] if we have an IRQ line. */
> or
> /* If no IRQ was specified, just return the error. */
>

Revert the change. Whilst not complex to follow it is non obvious to save only
a couple of lines. Adding a comment would take almost as much space as just doing
it the 'easy way'.

>>> + if (err && irq > 0)
>>> goto st_press_device_register_error;
>>>
>>> return err;
>>>
>>> st_press_device_register_error:
>>> - if (pdata->get_irq_data_ready(indio_dev) > 0)
>>> - st_sensors_deallocate_trigger(indio_dev);
>>> + st_sensors_deallocate_trigger(indio_dev);
>>> st_press_probe_trigger_error:
>>> - if (pdata->get_irq_data_ready(indio_dev) > 0)
>>> - st_press_deallocate_ring(indio_dev);
>>> -st_press_common_probe_error:
>>> + st_press_deallocate_ring(indio_dev);
>>> +
>>> return err;
>>> }
>>> EXPORT_SYMBOL(st_press_common_probe);
>>
>