PCI: revert "pcie: utilize pcie transaction pending bit"

Revert as it is reported to cause problems for people.

commit 4348a2dc49f9baecd34a9b0904245488c6189398
Author: Shaohua Li <[e-mail]>
Date: Wed Oct 24 10:45:08 2007 +0800

pcie: utilize pcie transaction pending bit

PCIE has a mechanism to wait for Non-Posted request to complete. I think
pci_disable_device is a good place to do this.

Signed-off-by: Shaohua Li <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

Due to the regression reported at
http://bugzilla.kernel.org/show_bug.cgi?id=10065

Cc: Shaohua Li <[e-mail]>
Cc: Soeren Sonnenburg <[e-mail]>
Cc: "Rafael J. Wysocki" <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/pci/pci.c

···
 }
 EXPORT_SYMBOL_GPL(pci_find_ht_capability);
 
-void pcie_wait_pending_transaction(struct pci_dev *dev)
-{
-	int pos;
-	u16 reg16;
-
-	pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
-	if (!pos)
-		return;
-	while (1) {
-		pci_read_config_word(dev, pos + PCI_EXP_DEVSTA, &reg16);
-		if (!(reg16 & PCI_EXP_DEVSTA_TRPND))
-			break;
-		cpu_relax();
-	}
-
-}
-EXPORT_SYMBOL_GPL(pcie_wait_pending_transaction);
-
 /**
  * pci_find_parent_resource - return resource region of parent bus of given region
  * @dev: PCI device structure contains resources to be searched
···
 
 	if (atomic_sub_return(1, &dev->enable_cnt) != 0)
 		return;
-
-	/* Wait for all transactions are finished before disabling the device */
-	pcie_wait_pending_transaction(dev);
 
 	pci_read_config_word(dev, PCI_COMMAND, &pci_command);
 	if (pci_command & PCI_COMMAND_MASTER) {

include/linux/pci.h

···
 int pci_find_ext_capability(struct pci_dev *dev, int cap);
 int pci_find_ht_capability(struct pci_dev *dev, int ht_cap);
 int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap);
-void pcie_wait_pending_transaction(struct pci_dev *dev);
 struct pci_bus *pci_find_next_bus(const struct pci_bus *from);
 
 struct pci_dev *pci_get_device(unsigned int vendor, unsigned int device,
···
 {
 	return 0;
 }
-
-static inline void pcie_wait_pending_transaction(struct pci_dev *dev)
-{ }
 
 /* Power management related routines */
 static inline int pci_save_state(struct pci_dev *dev)