Am Donnerstag, dem 21.07.2022 um 16:06 -0700 schrieb Saravana Kannan:
> On Tue, Jul 13, 2021 at 11:18 PM Martin Kepplinger
> <martin.kepplinger@xxxxxxx> wrote:
> >
> > Similar as with tcpm this patch lets fw_devlink know not to wait on
> > the
> > fwnode to be populated as a struct device.
> >
> > Without this patch, USB functionality can be broken on some
> > previously
> > supported boards.
> >
> > Fixes: 28ec344bb891 ("usb: typec: tcpm: Don't block probing of
> > consumers of "connector" nodes")
> > Signed-off-by: Martin Kepplinger <martin.kepplinger@xxxxxxx>
> > ---
> >
> > revision history
> > ----------------
> > v2: (thank you Saravana)
> > * add a code-comment why the call is needed.
> >
> > v1:
> > https://lore.kernel.org/linux-usb/20210713073946.102501-1-martin.kepplinger@xxxxxxx/
> >
> >
> >
> > drivers/usb/typec/tipd/core.c | 9 +++++++++
> > 1 file changed, 9 insertions(+)
> >
> > diff --git a/drivers/usb/typec/tipd/core.c
> > b/drivers/usb/typec/tipd/core.c
> > index 938219bc1b4b..21b3ae25c76d 100644
> > --- a/drivers/usb/typec/tipd/core.c
> > +++ b/drivers/usb/typec/tipd/core.c
> > @@ -629,6 +629,15 @@ static int tps6598x_probe(struct i2c_client
> > *client)
> > if (!fwnode)
> > return -ENODEV;
> >
> > + /*
> > + * This fwnode has a "compatible" property, but is never
> > populated as a
> > + * struct device. Instead we simply parse it to read the
> > properties.
> > + * This breaks fw_devlink=on. To maintain backward
> > compatibility
> > + * with existing DT files, we work around this by deleting
> > any
> > + * fwnode_links to/from this fwnode.
> > + */
> > + fw_devlink_purge_absent_suppliers(fwnode);
> > +
>
> Hey Martin,
>
> As part of a series I'm working on, I'm looking into deleting
> fw_devlink_purge_absent_suppliers() and having the driver core figure
> this out automatically.
>
> So I was making sure all the current uses of
> fw_devlink_purge_absent_suppliers() would automatically be handled by
> driver core. But when I looked at this usage of
> fw_devlink_purge_absent_suppliers(), I didn't see any "compatible"
> property in the "connector" child node. So, I'm confused how you had
> a
> problem without this patch.
>
> fw_devlink would have created fwnode links
> between typec_pd and usb_dwc3_0, figured out it's a cycle and have
> stopped enforcing the "remote-endpoint" dependencies.
>
> Can you give me more details please on why you were having a problem
> without this patch?
>
> I'm looking at arch/arm64/boot/dts/freescale/imx8mq-librem5.dtsi as
> an
> example because you listed it in your v1 patch.
>
> -Saravana
It's downstream. I'm very sorry about that. The patch that adds the
compatible string (
https://source.puri.sm/martin.kepplinger/linux-next/-/commit/3d887ea76158851ae50f192094d7865cc3f4da9d
) sits in our tree (
https://source.puri.sm/martin.kepplinger/linux-next/-/commits/5.19-rc7/librem5__integration
) and I'll make sure it'll be sent out after I'm back from vacations in
a few weeks.
Sorry for the confusion!
martin
>
> > tps->role_sw = fwnode_usb_role_switch_get(fwnode);
> > if (IS_ERR(tps->role_sw)) {
> > ret = PTR_ERR(tps->role_sw);
> > --
> > 2.30.2
> >
