[PATCH] shpchp: cleanup bus speed handling

The code related to handling bus speed in SHPCHP driver is
unnecessarily complex. This patch cleans up and simplify that.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 36 insertions, 116 deletions

diff --git a/drivers/pci/hotplug/shpchp_ctrl.c b/drivers/pci/hotplug/shpchp_ctrl.c
index 10f3257b18a7..4e6381481c55 100644
--- a/drivers/pci/hotplug/shpchp_ctrl.c
+++ b/drivers/pci/hotplug/shpchp_ctrl.c
@@ -198,7 +198,8 @@ static int change_bus_speed(struct controller *ctrl, struct slot *p_slot,
 
         dbg("%s: change to speed %d\n", __FUNCTION__, speed);
         if ((rc = p_slot->hpc_ops->set_bus_speed_mode(p_slot, speed))) {
-                err("%s: Issue of set bus speed mode command failed\n", __FUNCTION__);
+                err("%s: Issue of set bus speed mode command failed\n",
+                    __FUNCTION__);
                 return WRONG_BUS_FREQUENCY;
         }
         return rc;
@@ -209,33 +210,26 @@ static int fix_bus_speed(struct controller *ctrl, struct slot *pslot,
                 enum pci_bus_speed msp)
 { 
         int rc = 0;
-        
-        if (flag != 0) { /* Other slots on the same bus are occupied */
-                if ( asp < bsp ) {
-                        err("%s: speed of bus %x and adapter %x mismatch\n", __FUNCTION__, bsp, asp);
-                        return WRONG_BUS_FREQUENCY;
+
+        /*
+         * If other slots on the same bus are occupied, we cannot
+         * change the bus speed.
+         */
+        if (flag) {
+                if (asp < bsp) {
+                        err("%s: speed of bus %x and adapter %x mismatch\n",
+                            __FUNCTION__, bsp, asp);
+                        rc = WRONG_BUS_FREQUENCY;
                 }
+                return rc;
+        }
+
+        if (asp < msp) {
+                if (bsp != asp)
+                        rc = change_bus_speed(ctrl, pslot, asp);
         } else {
-                /* Other slots on the same bus are empty */
-                if (msp == bsp) {
-                /* if adapter_speed >= bus_speed, do nothing */
-                        if (asp < bsp) {
-                                /* 
-                                * Try to lower bus speed to accommodate the adapter if other slots 
-                                * on the same controller are empty
-                                */
-                                if ((rc = change_bus_speed(ctrl, pslot, asp)))
-                                        return rc;
-                        } 
-                } else {
-                        if (asp < msp) {
-                                if ((rc = change_bus_speed(ctrl, pslot, asp)))
-                                        return rc;
-                        } else {
-                                if ((rc = change_bus_speed(ctrl, pslot, msp)))
-                                        return rc;
-                        }
-                }
+                if (bsp != msp)
+                        rc = change_bus_speed(ctrl, pslot, msp);
         }
         return rc;
 }
@@ -252,8 +246,7 @@ static int board_added(struct slot *p_slot)
         u8 hp_slot;
         u8 slots_not_empty = 0;
         int rc = 0;
-        enum pci_bus_speed adapter_speed, bus_speed, max_bus_speed;
-        u8 pi, mode;
+        enum pci_bus_speed asp, bsp, msp;
         struct controller *ctrl = p_slot->ctrl;
 
         hp_slot = p_slot->device - ctrl->slot_device_offset;
@@ -285,109 +278,36 @@ static int board_added(struct slot *p_slot)
                 }
         }
  
-        rc = p_slot->hpc_ops->get_adapter_speed(p_slot, &adapter_speed);
-        /* 0 = PCI 33Mhz, 1 = PCI 66 Mhz, 2 = PCI-X 66 PA, 4 = PCI-X 66 ECC, */
-        /* 5 = PCI-X 133 PA, 7 = PCI-X 133 ECC,  0xa = PCI-X 133 Mhz 266, */
-        /* 0xd = PCI-X 133 Mhz 533 */
-        /* This encoding is different from the one used in cur_bus_speed & */
-        /* max_bus_speed */
-
-        if (rc  || adapter_speed == PCI_SPEED_UNKNOWN) {
-                err("%s: Can't get adapter speed or bus mode mismatch\n", __FUNCTION__);
+        rc = p_slot->hpc_ops->get_adapter_speed(p_slot, &asp);
+        if (rc) {
+                err("%s: Can't get adapter speed or bus mode mismatch\n",
+                    __FUNCTION__);
                 return WRONG_BUS_FREQUENCY;
         }
 
-        rc = p_slot->hpc_ops->get_cur_bus_speed(p_slot, &bus_speed);
-        if (rc || bus_speed == PCI_SPEED_UNKNOWN) {
+        rc = p_slot->hpc_ops->get_cur_bus_speed(p_slot, &bsp);
+        if (rc) {
                 err("%s: Can't get bus operation speed\n", __FUNCTION__);
                 return WRONG_BUS_FREQUENCY;
         }
 
-        rc = p_slot->hpc_ops->get_max_bus_speed(p_slot, &max_bus_speed);
-        if (rc || max_bus_speed == PCI_SPEED_UNKNOWN) {
+        rc = p_slot->hpc_ops->get_max_bus_speed(p_slot, &msp);
+        if (rc) {
                 err("%s: Can't get max bus operation speed\n", __FUNCTION__);
-                max_bus_speed = bus_speed;
-        }
-
-        if ((rc  = p_slot->hpc_ops->get_prog_int(p_slot, &pi))) {
-                err("%s: Can't get controller programming interface, set it to 1\n", __FUNCTION__);
-                pi = 1;
+                msp = bsp;
         }
 
         /* Check if there are other slots or devices on the same bus */
         if (!list_empty(&ctrl->pci_dev->subordinate->devices))
                 slots_not_empty = 1;
 
-        dbg("%s: slots_not_empty %d, pi %d\n", __FUNCTION__, 
-                slots_not_empty, pi);
-        dbg("adapter_speed %d, bus_speed %d, max_bus_speed %d\n", 
-                adapter_speed, bus_speed, max_bus_speed);
-
-        if (pi == 2) {
-                dbg("%s: In PI = %d\n", __FUNCTION__, pi);
-                if ((rc = p_slot->hpc_ops->get_mode1_ECC_cap(p_slot, &mode))) {
-                        err("%s: Can't get Mode1_ECC, set mode to 0\n", __FUNCTION__);
-                        mode = 0;
-                }
+        dbg("%s: slots_not_empty %d, adapter_speed %d, bus_speed %d, "
+            "max_bus_speed %d\n", __FUNCTION__, slots_not_empty, asp,
+            bsp, msp);
 
-                switch (adapter_speed) {
-                case PCI_SPEED_133MHz_PCIX_533:
-                case PCI_SPEED_133MHz_PCIX_266:
-                        if ((bus_speed != adapter_speed) &&
-                           ((rc = fix_bus_speed(ctrl, p_slot, slots_not_empty, adapter_speed, bus_speed, max_bus_speed)))) 
-                                return rc;
-                        break;  
-                case PCI_SPEED_133MHz_PCIX_ECC:
-                case PCI_SPEED_133MHz_PCIX:
-                        if (mode) { /* Bus - Mode 1 ECC */
-                                if ((bus_speed != 0x7) &&
-                                   ((rc = fix_bus_speed(ctrl, p_slot, slots_not_empty, adapter_speed, bus_speed, max_bus_speed)))) 
-                                        return rc;
-                        } else {
-                                if ((bus_speed != 0x4) &&
-                                   ((rc = fix_bus_speed(ctrl, p_slot, slots_not_empty, adapter_speed, bus_speed, max_bus_speed)))) 
-                                        return rc;
-                        }
-                        break;
-                case PCI_SPEED_66MHz_PCIX_ECC:
-                case PCI_SPEED_66MHz_PCIX:
-                        if (mode) { /* Bus - Mode 1 ECC */
-                                if ((bus_speed != 0x5) &&
-                                   ((rc = fix_bus_speed(ctrl, p_slot, slots_not_empty, adapter_speed, bus_speed, max_bus_speed)))) 
-                                        return rc;
-                        } else {
-                                if ((bus_speed != 0x2) &&
-                                   ((rc = fix_bus_speed(ctrl, p_slot, slots_not_empty, adapter_speed, bus_speed, max_bus_speed)))) 
-                                        return rc;
-                        }
-                        break;
-                case PCI_SPEED_66MHz:
-                        if ((bus_speed != 0x1) &&
-                           ((rc = fix_bus_speed(ctrl, p_slot, slots_not_empty, adapter_speed, bus_speed, max_bus_speed)))) 
-                                return rc;
-                        break;  
-                case PCI_SPEED_33MHz:
-                        if (bus_speed > 0x0) {
-                                if (slots_not_empty == 0) {
-                                        if ((rc = change_bus_speed(ctrl, p_slot, adapter_speed)))
-                                                return rc;
-                                } else {
-                                        err("%s: speed of bus %x and adapter %x mismatch\n", __FUNCTION__, bus_speed, adapter_speed);
-                                        return WRONG_BUS_FREQUENCY;
-                                }
-                        }
-                        break;
-                default:
-                        err("%s: speed of bus %x and adapter %x mismatch\n", __FUNCTION__, bus_speed, adapter_speed);
-                        return WRONG_BUS_FREQUENCY;
-                }
-        } else {
-                /* If adpater_speed == bus_speed, nothing to do here */
-                dbg("%s: In PI = %d\n", __FUNCTION__, pi);
-                if ((adapter_speed != bus_speed) &&
-                   ((rc = fix_bus_speed(ctrl, p_slot, slots_not_empty, adapter_speed, bus_speed, max_bus_speed))))
-                                return rc;
-        }
+        rc = fix_bus_speed(ctrl, p_slot, slots_not_empty, asp, bsp, msp);
+        if (rc)
+                return rc;
 
         /* turn on board, blink green LED, turn off Amber LED */
         if ((rc = p_slot->hpc_ops->slot_enable(p_slot))) {