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

Revert as it is reported to cause problems for people.

commit 4348a2dc
Author: Shaohua Li <shaohua.li@intel.com>
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: NShaohua Li <shaohua.li@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

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

Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Soeren Sonnenburg <kernel@nn7.de>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/pci/pci.c

@@ -314,24 +314,6 @@ int pci_find_ht_capability(struct pci_dev *dev, int ht_cap)
 }
 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
@@ -936,9 +918,6 @@ pci_disable_device(struct pci_dev *dev)
 	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) {
 		pci_command &= ~PCI_COMMAND_MASTER;

include/linux/pci.h

@@ -513,7 +513,6 @@ int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap);
 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,
@@ -884,9 +883,6 @@ static inline int pci_find_ext_capability(struct pci_dev *dev, int cap)
 	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)
 {