On Tue, 3 Jun 2025 00:25:40 +0300
Andy Shevchenko <andy.shevchenko@xxxxxxxxx> wrote:
> Mon, Jun 02, 2025 at 02:15:23PM -0300, Jonathan Santos kirjoitti:
> > On 05/30, Andy Shevchenko wrote:
> > > On Thu, May 29, 2025 at 07:50:29PM -0300, Jonathan Santos wrote:
>
> ...
>
> > > > +static int ad7768_trigger_sources_sync_setup(struct device *dev,
> > > > + struct fwnode_handle *dev_fwnode,
> > > > + struct ad7768_state *st)
> > > > +{
> > > > + struct fwnode_reference_args args;
> > > > +
> > > > + struct fwnode_handle *fwnode __free(fwnode_handle) =
> > > > + fwnode_find_reference_args(dev_fwnode, "trigger-sources",
> > > > + "#trigger-source-cells", 0,
> > > > + AD7768_TRIGGER_SOURCE_SYNC_IDX, &args);
> > >
> > > I don't see how args are being used. This puts in doubt the need of the first
> > > patch.
> >
> > If the wrapper is the issue, maybe it is better doing this instead?
> >
> > static int ad7768_trigger_sources_sync_setup(struct device *dev,
> > struct fwnode_handle *dev_fwnode,
>
> Name it fwnode...
>
> > struct ad7768_state *st)
> > {
> > struct fwnode_reference_args args;
> > struct fwnode_handle *fwnode __free(fwnode_handle) = NULL;
>
> ...and this one something like 'ref'. Also I'm not sure the __free() will do
> what you expect from it.
>
> > int ret;
> >
> > ret = fwnode_property_get_reference_args(dev_fwnode, "trigger-sources",
> > "#trigger-source-cells", 0,
> > AD7768_TRIGGER_SOURCE_SYNC_IDX, &args);
> > if (ret)
> > return ret;
> >
> > fwnode = args.fwnode;
>
> Yes, please. This looks better.
Take a look at the guidance in cleanup.h first. Linus made it very clear
that the = NULL then set it later pattern was not the way to go. That was
one of the things buried deep in a discussion thread soon after the cleanup.h
stuff was proposed and the lack of general knowledge of that preference lead
to Dan adding that documentation to cleanup.h.
If __free is used Linus always wants to see the constructor and destructor in the same line.
That is why I suggested the approach in patch 1.
If that isn't acceptable (yet), wrap this up in a local function doing the equivalent
of patch 1 and we can wait and see how common this ends up being.
Jonathan
>
> > > > + /* First, try getting the GPIO trigger source */
> > > > + if (fwnode_device_is_compatible(fwnode, "gpio-trigger")) {
> > > > + st->gpio_sync_in = devm_fwnode_gpiod_get_index(dev, fwnode,
> > > > + NULL,
> > > > + 0,
> > > > + GPIOD_OUT_LOW,
> > > > + "sync-in");
> > > > + return PTR_ERR_OR_ZERO(st->gpio_sync_in);
> > > > + }
> > > > +
> > > > + /*
> > > > + * TODO: Support the other cases when we have a trigger subsystem
> > > > + * to reliably handle other types of devices as trigger sources.
> > > > + *
> > > > + * For now, return an error message. For self triggering, omit the
> > > > + * trigger-sources property.
> > > > + */
> > > > + return dev_err_probe(dev, -EOPNOTSUPP, "Invalid synchronization trigger source\n");
> > > > +}
> >
> > Then we can get rid of the first patch.
>
