Merge tag 'stable/for-linus-3.4-tag' of git://git.kernel.org/pub/scm/linux/kernel...

[firefly-linux-kernel-4.4.55.git] / drivers / pci / pci.c

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index af295bb21d62890020cc2c0084f3570bd42babdc..053670e09e2b93bafa15e3662c8672fdebd8ef34 100644 (file)
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -3162,6 +3162,31 @@ int __pci_reset_function(struct pci_dev *dev)
 }
 EXPORT_SYMBOL_GPL(__pci_reset_function);
 
+/**
+ * __pci_reset_function_locked - reset a PCI device function while holding
+ * the @dev mutex lock.
+ * @dev: PCI device to reset
+ *
+ * Some devices allow an individual function to be reset without affecting
+ * other functions in the same device.  The PCI device must be responsive
+ * to PCI config space in order to use this function.
+ *
+ * The device function is presumed to be unused and the caller is holding
+ * the device mutex lock when this function is called.
+ * Resetting the device will make the contents of PCI configuration space
+ * random, so any caller of this must be prepared to reinitialise the
+ * device including MSI, bus mastering, BARs, decoding IO and memory spaces,
+ * etc.
+ *
+ * Returns 0 if the device function was successfully reset or negative if the
+ * device doesn't support resetting a single function.
+ */
+int __pci_reset_function_locked(struct pci_dev *dev)
+{
+       return pci_dev_reset(dev, 1);
+}
+EXPORT_SYMBOL_GPL(__pci_reset_function_locked);
+
 /**
  * pci_probe_reset_function - check whether the device can be safely reset
  * @dev: PCI device to reset