Ages ago, drivers could return values greater than zero from their probe
function and this would be regarded as success.
But after f3ec4f87d6 ("PCI: change device runtime PM settings for probe
and remove") and 967577b062 ("PCI/PM: Keep runtime PM enabled for unbound
PCI devices"), we set dev->driver to NULL if the driver's probe function
returns a value greater than zero.
__pci_device_probe() treats this as success, and drivers can still mostly
work even with dev->driver == NULL, but PCI power management doesn't work,
and we don't call the driver's remove function on rmmod.
To help catch these driver problems, issue a warning in this case.
[bhelgaas: changelog]
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>