Staging: ipack/bridges/tpci200: Cleanup in tpci200_slot_irq() and tpci200_interrupt()

Minor cleanup.  No functional changes.

Signed-off-by: Jens Taprogge <jens.taprogge@taprogge.org>
Signed-off-by: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 31 insertions, 27 deletions

diff --git a/drivers/staging/ipack/bridges/tpci200.c b/drivers/staging/ipack/bridges/tpci200.c
index 0cbaf3ab53cd..4eaa2aaec24d 100644
--- a/drivers/staging/ipack/bridges/tpci200.c
+++ b/drivers/staging/ipack/bridges/tpci200.c
@@ -102,9 +102,13 @@ static void tpci200_unregister(struct tpci200_board *tpci200)
 
 static irqreturn_t tpci200_slot_irq(struct slot_irq *slot_irq)
 {
-        irqreturn_t ret = slot_irq->handler(slot_irq->arg);
+        irqreturn_t ret;
 
-        /* Dummy reads */
+        if (!slot_irq)
+                return -ENODEV;
+        ret = slot_irq->handler(slot_irq->arg);
+
+        /* Clear the IPack device interrupt */
         readw(slot_irq->holder->io_space.address + 0xC0);
         readw(slot_irq->holder->io_space.address + 0xC2);
 
@@ -114,37 +118,37 @@ static irqreturn_t tpci200_slot_irq(struct slot_irq *slot_irq)
 static irqreturn_t tpci200_interrupt(int irq, void *dev_id)
 {
         struct tpci200_board *tpci200 = (struct tpci200_board *) dev_id;
-        int i;
-        unsigned short status_reg;
         struct slot_irq *slot_irq;
+        irqreturn_t ret;
+        u16 status_reg;
+        int i;
 
         /* Read status register */
-        status_reg = readw(&tpci200->info->interface_regs->status);
-
-        if (status_reg & TPCI200_SLOT_INT_MASK) {
-                /* callback to the IRQ handler for the corresponding slot */
-                rcu_read_lock();
-                for (i = 0; i < TPCI200_NB_SLOT; i++) {
-                        if (!(status_reg & ((TPCI200_A_INT0 | TPCI200_A_INT1) << (2*i))))
-                                continue;
-                        slot_irq = rcu_dereference(tpci200->slots[i].irq);
-                        if (slot_irq) {
-                                tpci200_slot_irq(slot_irq);
-                        } else {
-                                dev_info(&tpci200->info->pdev->dev,
-                                         "No registered ISR for slot [%d:%d]!. IRQ will be disabled.\n",
-                                         tpci200->number, i);
-                                tpci200_clear_mask(tpci200,
-                                        &tpci200->info->interface_regs->control[i],
-                                        TPCI200_INT0_EN | TPCI200_INT1_EN);
-                        }
-                }
-                rcu_read_unlock();
+        status_reg = ioread16(&tpci200->info->interface_regs->status);
 
-                return IRQ_HANDLED;
-        } else {
+        /* Did we cause the interrupt? */
+        if (!(status_reg & TPCI200_SLOT_INT_MASK))
                 return IRQ_NONE;
+
+        /* callback to the IRQ handler for the corresponding slot */
+        rcu_read_lock();
+        for (i = 0; i < TPCI200_NB_SLOT; i++) {
+                if (!(status_reg & ((TPCI200_A_INT0 | TPCI200_A_INT1) << (2 * i))))
+                        continue;
+                slot_irq = rcu_dereference(tpci200->slots[i].irq);
+                ret = tpci200_slot_irq(slot_irq);
+                if (ret == -ENODEV) {
+                        dev_info(&tpci200->info->pdev->dev,
+                                 "No registered ISR for slot [%d:%d]!. IRQ will be disabled.\n",
+                                 tpci200->number, i);
+                        tpci200_clear_mask(tpci200,
+                                &tpci200->info->interface_regs->control[i],
+                                TPCI200_INT0_EN | TPCI200_INT1_EN);
+                }
         }
+        rcu_read_unlock();
+
+        return IRQ_HANDLED;
 }
 
 static int tpci200_register(struct tpci200_board *tpci200)