Hi Greg, On Thu, Jun 18, 2020 at 10:14:43AM +0200, Greg Kroah-Hartman wrote: > On Wed, Jun 03, 2020 at 12:09:52AM +0530, Sandeep Maheswaram wrote: > > Export the symbol device_is_bound so that it can be used by the modules. > > What modules need this? drivers/usb/dwc3/dwc3-qcom.c (and probably other dwc3 'wrappers'). Short summary: QCOM dwc3 support is split in two drivers, the core dwc3 driver and the QCOM specific parts. dwc3-qcom is probed first (through a DT entry or ACPI), dwc3_qcom_probe() then calls of_platform_populate() to probe the core part. After a successful return from _populate() the driver assumes that the core device is fully initialized. However the latter is not correct, the driver core doesn't propagate errors from probe() to platform_populate(). The dwc3-qcom driver would use device_is_bound() to make sure the core device was probed successfully. Related patches: "usb: dwc3: qcom: Make sure core device is fully initialized before it is used" https://lore.kernel.org/patchwork/patch/1257279/ "usb: dwc3: qcom: Add interconnect support in dwc3 driver" https://patchwork.kernel.org/patch/11468647/ > > This change was suggested to solve the allmodconfig build error on adding > > the patch https://lore.kernel.org/patchwork/patch/1218628/ > > > > Signed-off-by: Sandeep Maheswaram <sanm@xxxxxxxxxxxxxx> > > --- > > drivers/base/dd.c | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/drivers/base/dd.c b/drivers/base/dd.c > > index 9a1d940..65d16ce 100644 > > --- a/drivers/base/dd.c > > +++ b/drivers/base/dd.c > > @@ -337,6 +337,7 @@ bool device_is_bound(struct device *dev) > > { > > return dev->p && klist_node_attached(&dev->p->knode_driver); > > } > > +EXPORT_SYMBOL_GPL(device_is_bound); > > If a driver needs to use this, something is really wrong with it. What > happens right after this, the state could have changed? > > So, no, sorry, this is not a good idea. Agreed that what some dwc3 'wrapper' drivers do is brittle, and that using device_is_bound() is only a bandaid, that doesn't address the entire issue. Do you have any suggestions on how this could be properly addressed? Thanks Matthias
