Staging: ipack/bridges/tpci200: Put the TPCI200 control registers into a struct.

This saves us from a little pointer arithmetic and cleans up the code a bit.
Signed-off-by: Jens Taprogge <jens.taprogge@taprogge.org>
Signed-off-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/ipack/bridges/tpci200.c

@@ -14,14 +14,6 @@
 #include <linux/module.h>
 #include "tpci200.h"
 
-/* TPCI200 controls registers */
-static const int control_reg[] = {
-	TPCI200_CONTROL_A_REG,
-	TPCI200_CONTROL_B_REG,
-	TPCI200_CONTROL_C_REG,
-	TPCI200_CONTROL_D_REG
-};
-
 static int tpci200_slot_unregister(struct ipack_device *dev);
 
 static struct tpci200_board *check_slot(struct ipack_device *dev)
@@ -85,8 +77,7 @@ static irqreturn_t tpci200_interrupt(int irq, void *dev_id)
 	irqreturn_t ret = IRQ_NONE;
 
 	/* Read status register */
-	status_reg = readw(tpci200->info->interface_regs +
-			   TPCI200_STATUS_REG);
+	status_reg = readw(&tpci200->info->interface_regs->status);
 
 	if (status_reg & TPCI200_SLOT_INT_MASK) {
 		unhandled_ints = status_reg & TPCI200_SLOT_INT_MASK;
@@ -107,7 +98,7 @@ static irqreturn_t tpci200_interrupt(int irq, void *dev_id)
 			}
 		}
 	}
-	/* Interrupt not handled are disabled */
+	/* Interrupts not handled are disabled */
 	if (unhandled_ints) {
 		for (i = 0; i < TPCI200_NB_SLOT; i++) {
 			if (unhandled_ints & ((TPCI200_INT0_EN | TPCI200_INT1_EN) << (2*i))) {
@@ -115,13 +106,11 @@ static irqreturn_t tpci200_interrupt(int irq, void *dev_id)
 					 "No registered ISR for slot [%d:%d]!. IRQ will be disabled.\n",
 					 tpci200->number, i);
 				reg_value = readw(
-					tpci200->info->interface_regs +
-					control_reg[i]);
+					&tpci200->info->interface_regs->control[i]);
 				reg_value &=
 					~(TPCI200_INT0_EN | TPCI200_INT1_EN);
 				writew(reg_value,
-				       (tpci200->info->interface_regs +
-					control_reg[i]));
+				       &tpci200->info->interface_regs->control[i]);
 			}
 		}
 	}
@@ -219,8 +208,7 @@ static int tpci200_register(struct tpci200_board *tpci200)
 			(void __iomem *)mem_base + TPCI200_MEM8_GAP*i;
 		tpci200->slots[i].mem_phys.size = TPCI200_MEM8_SIZE;
 
-		writew(slot_ctrl, (tpci200->info->interface_regs +
-				   control_reg[i]));
+		writew(slot_ctrl, &tpci200->info->interface_regs->control[i]);
 	}
 
 	res = request_irq(tpci200->info->pdev->irq,
@@ -259,8 +247,7 @@ static int __tpci200_request_irq(struct tpci200_board *tpci200,
 	 * clock rate 8 MHz
 	 */
 	slot_ctrl = TPCI200_INT0_EN | TPCI200_INT1_EN;
-	writew(slot_ctrl, (tpci200->info->interface_regs +
-			   control_reg[dev->slot]));
+	writew(slot_ctrl, &tpci200->info->interface_regs->control[dev->slot]);
 
 	return 0;
 }
@@ -279,8 +266,7 @@ static void __tpci200_free_irq(struct tpci200_board *tpci200,
 	 * clock rate 8 MHz
 	 */
 	slot_ctrl = 0;
-	writew(slot_ctrl, (tpci200->info->interface_regs +
-			   control_reg[dev->slot]));
+	writew(slot_ctrl, &tpci200->info->interface_regs->control[dev->slot]);
 }
 
 static int tpci200_free_irq(struct ipack_device *dev)

drivers/staging/ipack/bridges/tpci200.h

@@ -37,13 +37,15 @@
 #define TPCI200_MEM16_SPACE_BAR       4
 #define TPCI200_MEM8_SPACE_BAR        5
 
-#define TPCI200_REVISION_REG          0x00
-#define TPCI200_CONTROL_A_REG         0x02
-#define TPCI200_CONTROL_B_REG         0x04
-#define TPCI200_CONTROL_C_REG         0x06
-#define TPCI200_CONTROL_D_REG         0x08
-#define TPCI200_RESET_REG             0x0A
-#define TPCI200_STATUS_REG            0x0C
+struct tpci200_regs {
+	u16	revision;
+	/* writes to control should occur with the mutex held to protect
+	 * read-modify-write operations */
+	u16  control[4];
+	u16	reset;
+	u16	status;
+	u8	reserved[242];
+} __packed;
 
 #define TPCI200_IFACE_SIZE            0x100
 
@@ -63,6 +65,7 @@
 #define TPCI200_MEM16_GAP             0x00800000
 #define TPCI200_MEM16_SIZE            0x00800000
 
+/* control field in tpci200_regs */
 #define TPCI200_INT0_EN               0x0040
 #define TPCI200_INT1_EN               0x0080
 #define TPCI200_INT0_EDGE             0x0010
@@ -72,11 +75,13 @@
 #define TPCI200_RECOVER_EN            0x0002
 #define TPCI200_CLK32                 0x0001
 
+/* reset field in tpci200_regs */
 #define TPCI200_A_RESET               0x0001
 #define TPCI200_B_RESET               0x0002
 #define TPCI200_C_RESET               0x0004
 #define TPCI200_D_RESET               0x0008
 
+/* status field in tpci200_regs */
 #define TPCI200_A_TIMEOUT             0x1000
 #define TPCI200_B_TIMEOUT             0x2000
 #define TPCI200_C_TIMEOUT             0x4000
@@ -149,7 +154,7 @@ struct tpci200_slot {
 struct tpci200_infos {
 	struct pci_dev			*pdev;
 	struct pci_device_id		*id_table;
-	void __iomem			*interface_regs;
+	struct tpci200_regs __iomem	*interface_regs;
 	void __iomem			*ioidint_space;
 	void __iomem			*mem8_space;
 	void __iomem			*cfg_regs;