PCIe: fix double initialization bug

Earlier patches to split out the hardware init for PCIe hotplug resulted in
some one-time initializations being redone on every resume cycle.  Eg.
irq/polling initialization.

This patch splits the hardware init into two parts, and separates the
one-time initializations from those so that they only ever get done once,
as intended.

Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

3 files changed, 69 insertions, 54 deletions

diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index e4ad00a3448e..288fc4689103 100644
--- a/drivers/pci/hotplug/pciehp.h
+++ b/drivers/pci/hotplug/pciehp.h
@@ -163,7 +163,7 @@ extern void pciehp_queue_pushbutton_work(struct work_struct *work);
 int pcie_init(struct controller *ctrl, struct pcie_device *dev);
 int pciehp_enable_slot(struct slot *p_slot);
 int pciehp_disable_slot(struct slot *p_slot);
-int pcie_init_hardware(struct controller *ctrl, struct pcie_device *dev);
+int pcie_init_hardware_part2(struct controller *ctrl, struct pcie_device *dev);
 
 static inline struct slot *pciehp_find_slot(struct controller *ctrl, u8 device)
 {
diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c
index ae3fe318b8fd..310223d037aa 100644
--- a/drivers/pci/hotplug/pciehp_core.c
+++ b/drivers/pci/hotplug/pciehp_core.c
@@ -521,7 +521,7 @@ static int pciehp_resume (struct pcie_device *dev)
                 u8 status;
 
                 /* reinitialize the chipset's event detection logic */
-                pcie_init_hardware(ctrl, dev);
+                pcie_init_hardware_part2(ctrl, dev);
 
                 t_slot = pciehp_find_slot(ctrl, ctrl->slot_device_offset);
 
diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index 8b11d80bf651..8c2d6c9b92c5 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -1067,28 +1067,25 @@ int pciehp_acpi_get_hp_hw_control_from_firmware(struct pci_dev *dev)
 }
 #endif
 
-int pcie_init_hardware(struct controller *ctrl, struct pcie_device *dev)
+static int pcie_init_hardware_part1(struct controller *ctrl,
+                                    struct pcie_device *dev)
 {
         int rc;
         u16 temp_word;
-        u16 intr_enable = 0;
         u32 slot_cap;
         u16 slot_status;
-        struct pci_dev *pdev;
-
-        pdev = dev->port;
 
         rc = pciehp_readl(ctrl, SLOTCAP, &slot_cap);
         if (rc) {
                 err("%s: Cannot read SLOTCAP register\n", __FUNCTION__);
-                goto abort_free_ctlr;
+                return -1;
         }
 
         /* Mask Hot-plug Interrupt Enable */
         rc = pciehp_readw(ctrl, SLOTCTRL, &temp_word);
         if (rc) {
                 err("%s: Cannot read SLOTCTRL register\n", __FUNCTION__);
-                goto abort_free_ctlr;
+                return -1;
         }
 
         dbg("%s: SLOTCTRL %x value read %x\n",
@@ -1099,62 +1096,46 @@ int pcie_init_hardware(struct controller *ctrl, struct pcie_device *dev)
         rc = pciehp_writew(ctrl, SLOTCTRL, temp_word);
         if (rc) {
                 err("%s: Cannot write to SLOTCTRL register\n", __FUNCTION__);
-                goto abort_free_ctlr;
+                return -1;
         }
 
         rc = pciehp_readw(ctrl, SLOTSTATUS, &slot_status);
         if (rc) {
                 err("%s: Cannot read SLOTSTATUS register\n", __FUNCTION__);
-                goto abort_free_ctlr;
+                return -1;
         }
 
         temp_word = 0x1F; /* Clear all events */
         rc = pciehp_writew(ctrl, SLOTSTATUS, temp_word);
         if (rc) {
                 err("%s: Cannot write to SLOTSTATUS register\n", __FUNCTION__);
-                goto abort_free_ctlr;
-        }
-
-        if (pciehp_poll_mode) {
-                /* Install interrupt polling timer. Start with 10 sec delay */
-                init_timer(&ctrl->poll_timer);
-                start_int_poll_timer(ctrl, 10);
-        } else {
-                /* Installs the interrupt handler */
-                rc = request_irq(ctrl->pci_dev->irq, pcie_isr, IRQF_SHARED,
-                                 MY_NAME, (void *)ctrl);
-                dbg("%s: request_irq %d for hpc%d (returns %d)\n",
-                    __FUNCTION__, ctrl->pci_dev->irq,
-                    atomic_read(&pciehp_num_controllers), rc);
-                if (rc) {
-                        err("Can't get irq %d for the hotplug controller\n",
-                            ctrl->pci_dev->irq);
-                        goto abort_free_ctlr;
-                }
+                return -1;
         }
-        dbg("pciehp ctrl b:d:f:irq=0x%x:%x:%x:%x\n", pdev->bus->number,
-                PCI_SLOT(pdev->devfn), PCI_FUNC(pdev->devfn), dev->irq);
+        return 0;
+}
 
-        /*
-         * If this is the first controller to be initialized,
-         * initialize the pciehp work queue
-         */
-        if (atomic_add_return(1, &pciehp_num_controllers) == 1) {
-                pciehp_wq = create_singlethread_workqueue("pciehpd");
-                if (!pciehp_wq) {
-                        rc = -ENOMEM;
-                        goto abort_free_irq;
-                }
-        }
+int pcie_init_hardware_part2(struct controller *ctrl, struct pcie_device *dev)
+{
+        int rc;
+        u16 temp_word;
+        u16 intr_enable = 0;
+        u32 slot_cap;
+        u16 slot_status;
 
         rc = pciehp_readw(ctrl, SLOTCTRL, &temp_word);
         if (rc) {
                 err("%s: Cannot read SLOTCTRL register\n", __FUNCTION__);
-                goto abort_free_irq;
+                goto abort;
         }
 
         intr_enable = intr_enable | PRSN_DETECT_ENABLE;
 
+        rc = pciehp_readl(ctrl, SLOTCAP, &slot_cap);
+        if (rc) {
+                err("%s: Cannot read SLOTCAP register\n", __FUNCTION__);
+                goto abort;
+        }
+
         if (ATTN_BUTTN(slot_cap))
                 intr_enable = intr_enable | ATTN_BUTTN_ENABLE;
 
@@ -1179,7 +1160,7 @@ int pcie_init_hardware(struct controller *ctrl, struct pcie_device *dev)
         rc = pciehp_writew(ctrl, SLOTCTRL, temp_word);
         if (rc) {
                 err("%s: Cannot write to SLOTCTRL register\n", __FUNCTION__);
-                goto abort_free_irq;
+                goto abort;
         }
         rc = pciehp_readw(ctrl, SLOTSTATUS, &slot_status);
         if (rc) {
@@ -1214,14 +1195,7 @@ abort_disable_intr:
         }
         if (rc)
                 err("%s : disabling interrupts failed\n", __FUNCTION__);
-
-abort_free_irq:
-        if (pciehp_poll_mode)
-                del_timer_sync(&ctrl->poll_timer);
-        else
-                free_irq(ctrl->pci_dev->irq, ctrl);
-
-abort_free_ctlr:
+abort:
         return -1;
 }
 
@@ -1318,11 +1292,52 @@ int pcie_init(struct controller *ctrl, struct pcie_device *dev)
         ctrl->first_slot = slot_cap >> 19;
         ctrl->ctrlcap = slot_cap & 0x0000007f;
 
-        rc = pcie_init_hardware(ctrl, dev);
+        rc = pcie_init_hardware_part1(ctrl, dev);
+        if (rc)
+                goto abort;
+
+        if (pciehp_poll_mode) {
+                /* Install interrupt polling timer. Start with 10 sec delay */
+                init_timer(&ctrl->poll_timer);
+                start_int_poll_timer(ctrl, 10);
+        } else {
+                /* Installs the interrupt handler */
+                rc = request_irq(ctrl->pci_dev->irq, pcie_isr, IRQF_SHARED,
+                                 MY_NAME, (void *)ctrl);
+                dbg("%s: request_irq %d for hpc%d (returns %d)\n",
+                    __FUNCTION__, ctrl->pci_dev->irq,
+                    atomic_read(&pciehp_num_controllers), rc);
+                if (rc) {
+                        err("Can't get irq %d for the hotplug controller\n",
+                            ctrl->pci_dev->irq);
+                        goto abort;
+                }
+        }
+        dbg("pciehp ctrl b:d:f:irq=0x%x:%x:%x:%x\n", pdev->bus->number,
+                PCI_SLOT(pdev->devfn), PCI_FUNC(pdev->devfn), dev->irq);
+
+        /*
+         * If this is the first controller to be initialized,
+         * initialize the pciehp work queue
+         */
+        if (atomic_add_return(1, &pciehp_num_controllers) == 1) {
+                pciehp_wq = create_singlethread_workqueue("pciehpd");
+                if (!pciehp_wq) {
+                        rc = -ENOMEM;
+                        goto abort_free_irq;
+                }
+        }
+
+        rc = pcie_init_hardware_part2(ctrl, dev);
         if (rc == 0) {
                 ctrl->hpc_ops = &pciehp_hpc_ops;
                 return 0;
         }
+abort_free_irq:
+        if (pciehp_poll_mode)
+                del_timer_sync(&ctrl->poll_timer);
+        else
+                free_irq(ctrl->pci_dev->irq, ctrl);
 abort:
         return -1;
 }