[PATCH 164/241] MISC: hpilo, remove pci_disable_device

[Herton Ronaldo Krzesinski]

3.5.7.2 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jiri Slaby <jslaby at suse.cz>

commit bcdee04ea7ae0406ae69094f6df1aacb66a69a0b upstream.

pci_disable_device(pdev) used to be in pci remove function. But this
PCI device has two functions with interrupt lines connected to a
single pin. The other one is a USB host controller. So when we disable
the PIN there e.g. by rmmod hpilo, the controller stops working. It is
because the interrupt link is disabled in ACPI since it is not
refcounted yet. See acpi_pci_link_free_irq called from
acpi_pci_irq_disable.

It is not the best solution whatsoever, but as a workaround until the
ACPI irq link refcounting is sorted out this should fix the reported
errors.

References: https://lkml.org/lkml/2008/11/4/535

Signed-off-by: Jiri Slaby <jslaby at suse.cz>
Cc: Grant Grundler <grundler at parisc-linux.org>
Cc: Nobin Mathew <nobin.mathew at gmail.com>
Cc: Robert Hancock <hancockr at shaw.ca>
Cc: Arnd Bergmann <arnd at arndb.de>
Cc: David Altobelli <david.altobelli at hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski at canonical.com>
---
 drivers/misc/hpilo.c |   11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/misc/hpilo.c b/drivers/misc/hpilo.c
index fffc227..9c99680 100644
--- a/drivers/misc/hpilo.c
+++ b/drivers/misc/hpilo.c
@@ -735,7 +735,14 @@ static void ilo_remove(struct pci_dev *pdev)
 	free_irq(pdev->irq, ilo_hw);
 	ilo_unmap_device(pdev, ilo_hw);
 	pci_release_regions(pdev);
-	pci_disable_device(pdev);
+	/*
+	 * pci_disable_device(pdev) used to be here. But this PCI device has
+	 * two functions with interrupt lines connected to a single pin. The
+	 * other one is a USB host controller. So when we disable the PIN here
+	 * e.g. by rmmod hpilo, the controller stops working. It is because
+	 * the interrupt link is disabled in ACPI since it is not refcounted
+	 * yet. See acpi_pci_link_free_irq called from acpi_pci_irq_disable.
+	 */
 	kfree(ilo_hw);
 	ilo_hwdev[(minor / MAX_CCB)] = 0;
 }
@@ -820,7 +827,7 @@ unmap:
 free_regions:
 	pci_release_regions(pdev);
 disable:
-	pci_disable_device(pdev);
+/*	pci_disable_device(pdev);  see comment in ilo_remove */
 free:
 	kfree(ilo_hw);
 out:
-- 
1.7.9.5