> -----Original Message-----
> From: Leon Romanovsky <leon@xxxxxxxxxx>
> Sent: Tuesday, October 6, 2020 10:23 AM
> To: Ertman, David M <david.m.ertman@xxxxxxxxx>
> Cc: alsa-devel@xxxxxxxxxxxxxxxx; tiwai@xxxxxxx; broonie@xxxxxxxxxx; linux-
> rdma@xxxxxxxxxxxxxxx; jgg@xxxxxxxxxx; dledford@xxxxxxxxxx;
> netdev@xxxxxxxxxxxxxxx; davem@xxxxxxxxxxxxx; kuba@xxxxxxxxxx;
> gregkh@xxxxxxxxxxxxxxxxxxx; ranjani.sridharan@xxxxxxxxxxxxxxx; pierre-
> louis.bossart@xxxxxxxxxxxxxxx; fred.oh@xxxxxxxxxxxxxxx;
> parav@xxxxxxxxxxxx; Saleem, Shiraz <shiraz.saleem@xxxxxxxxx>; Williams,
> Dan J <dan.j.williams@xxxxxxxxx>; Patil, Kiran <kiran.patil@xxxxxxxxx>
> Subject: Re: [PATCH v2 1/6] Add ancillary bus support
>
> On Mon, Oct 05, 2020 at 11:24:41AM -0700, Dave Ertman wrote:
> > Add support for the Ancillary Bus, ancillary_device and ancillary_driver.
> > It enables drivers to create an ancillary_device and bind an
> > ancillary_driver to it.
> >
> > The bus supports probe/remove shutdown and suspend/resume callbacks.
> > Each ancillary_device has a unique string based id; driver binds to
> > an ancillary_device based on this id through the bus.
> >
> > Co-developed-by: Kiran Patil <kiran.patil@xxxxxxxxx>
> > Signed-off-by: Kiran Patil <kiran.patil@xxxxxxxxx>
> > Co-developed-by: Ranjani Sridharan <ranjani.sridharan@xxxxxxxxxxxxxxx>
> > Signed-off-by: Ranjani Sridharan <ranjani.sridharan@xxxxxxxxxxxxxxx>
> > Co-developed-by: Fred Oh <fred.oh@xxxxxxxxxxxxxxx>
> > Signed-off-by: Fred Oh <fred.oh@xxxxxxxxxxxxxxx>
> > Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
> > Reviewed-by: Shiraz Saleem <shiraz.saleem@xxxxxxxxx>
> > Reviewed-by: Parav Pandit <parav@xxxxxxxxxxxx>
> > Reviewed-by: Dan Williams <dan.j.williams@xxxxxxxxx>
> > Signed-off-by: Dave Ertman <david.m.ertman@xxxxxxxxx>
> > ---
>
> <...>
>
> > +/**
> > + * __ancillary_driver_register - register a driver for ancillary bus devices
> > + * @ancildrv: ancillary_driver structure
> > + * @owner: owning module/driver
> > + */
> > +int __ancillary_driver_register(struct ancillary_driver *ancildrv, struct
> module *owner)
> > +{
> > + if (WARN_ON(!ancildrv->probe) || WARN_ON(!ancildrv->remove)
> ||
> > + WARN_ON(!ancildrv->shutdown) || WARN_ON(!ancildrv-
> >id_table))
> > + return -EINVAL;
>
> In our driver ->shutdown is empty, it will be best if ancillary bus will
> do "if (->remove) ..->remove()" pattern.
>
Yes, looking it over, only the probe needs to mandatory. I will change the others to the
conditional model, and adjust the WARN_ONs.
> > +
> > + ancildrv->driver.owner = owner;
> > + ancildrv->driver.bus = &ancillary_bus_type;
> > + ancildrv->driver.probe = ancillary_probe_driver;
> > + ancildrv->driver.remove = ancillary_remove_driver;
> > + ancildrv->driver.shutdown = ancillary_shutdown_driver;
> > +
>
> I think that this part is wrong, probe/remove/shutdown functions should
> come from ancillary_bus_type.
>From checking other usage cases, this is the model that is used for probe, remove,
and shutdown in drivers. Here is the example from Greybus.
int greybus_register_driver(struct greybus_driver *driver, struct module *owner,
const char *mod_name)
{
int retval;
if (greybus_disabled())
return -ENODEV;
driver->driver.bus = &greybus_bus_type;
driver->driver.name = driver->name;
driver->driver.probe = greybus_probe;
driver->driver.remove = greybus_remove;
driver->driver.owner = owner;
driver->driver.mod_name = mod_name;
> You are overwriting private device_driver
> callbacks that makes impossible to make container_of of ancillary_driver
> to chain operations.
>
I am sorry, you lost me here. you cannot perform container_of on the callbacks
because they are pointers, but if you are referring to going from device_driver
to the auxiliary_driver, that is what happens in auxiliary_probe_driver in the
very beginning.
static int auxiliary_probe_driver(struct device *dev)
145 {
146 struct auxiliary_driver *auxdrv = to_auxiliary_drv(dev->driver);
147 struct auxiliary_device *auxdev = to_auxiliary_dev(dev);
Did I miss your meaning?
-DaveE
> > + return driver_register(&ancildrv->driver);
> > +}
> > +EXPORT_SYMBOL_GPL(__ancillary_driver_register);
>
> Thanks
