Commit 3abcfe0e authored Sep 03, 2012 by Ian Abbott Committed by Greg Kroah-Hartman Sep 04, 2012

staging: comedi: amplc_pc236: Fix PCI ref count



When attaching a PCI device manually via the comedi driver `attach` hook
(`pc236_attach()`) (called by the comedi core for the `COMEDI_DEVCONFIG`
ioctl), its reference count is incremented in the `for_each_pci_dev`
loop (in `pc236_find_pci_dev()`).  It is decremented when the `detach`
hook (`pc236_detach()`) is called to detach the device.  However, when
the PCI device is attached automatically via the `attach_pci` hook
(`pc236_attach_pci()`, called at probe time via
`comedi_pci_auto_config()`) it's reference count is not incremented so
there will be an unmatched decrement when detaching the device.

Increment the PCI device reference count in `pc236_attach_pci()` to
correct the mismatch.

Once support for manual configuration has been removed from this driver,
the calls to `pci_dev_get()` and `pci_dev_put()` can be removed.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 1a6671d2

drivers/staging/comedi/drivers/amplc_pc236.c

+7 −0

Original line number	Diff line number	Diff line
		@@ -565,6 +565,13 @@ static int __devinit pc236_attach_pci(struct comedi_device *dev,
		dev_err(dev->class_dev, "BUG! cannot determine board type!\n");
		return -EINVAL;
		}
		/*
		* Need to 'get' the PCI device to match the 'put' in pc236_detach().
		* TODO: Remove the pci_dev_get() and matching pci_dev_put() once
		* support for manual attachment of PCI devices via pc236_attach()
		* has been removed.
		*/
		pci_dev_get(pci_dev);
		return pc236_pci_common_attach(dev, pci_dev);
		}