diff --git a/Documentation/sgi-ioc4.txt b/Documentation/sgi-ioc4.txt
new file mode 100644
index 0000000..876c96a
--- /dev/null
+++ b/Documentation/sgi-ioc4.txt
@@ -0,0 +1,45 @@
+The SGI IOC4 PCI device is a bit of a strange beast, so some notes on
+it are in order.
+
+First, even though the IOC4 performs multiple functions, such as an
+IDE controller, a serial controller, a PS/2 keyboard/mouse controller,
+and an external interrupt mechanism, it's not implemented as a
+multifunction device.  The consequence of this from a software
+standpoint is that all these functions share a single IRQ, and
+they can't all register to own the same PCI device ID.  To make
+matters a bit worse, some of the register blocks (and even registers
+themselves) present in IOC4 are mixed-purpose between these several
+functions, meaning that there's no clear "owning" device driver.
+
+The solution is to organize the IOC4 driver into several independent
+drivers, "ioc4", "sgiioc4", and "ioc4_serial".  Note that there is no
+PS/2 controller driver as this functionality has never been wired up
+on a shipping IO card.
+
+ioc4
+====
+This is the core (or shim) driver for IOC4.  It is responsible for
+initializing the basic functionality of the chip, and allocating
+the PCI resources that are shared between the IOC4 functions.
+
+This driver also provides registration functions that the other
+IOC4 drivers can call to make their presence known.  Each driver
+needs to provide a probe and remove function, which are invoked
+by the core driver at appropriate times.  The interface of these
+IOC4 function probe and remove operations isn't precisely the same
+as PCI device probe and remove operations, but is logically the
+same operation.
+
+sgiioc4
+=======
+This is the IDE driver for IOC4.  Its name isn't very descriptive
+simply for historical reasons (it used to be the only IOC4 driver
+component).  There's not much to say about it other than it hooks
+up to the ioc4 driver via the appropriate registration, probe, and
+remove functions.
+
+ioc4_serial
+===========
+This is the serial driver for IOC4.  There's not much to say about it
+other than it hooks up to the ioc4 driver via the appropriate registration,
+probe, and remove functions.
diff --git a/drivers/ide/pci/sgiioc4.c b/drivers/ide/pci/sgiioc4.c
index 4651a22..af526b6 100644
--- a/drivers/ide/pci/sgiioc4.c
+++ b/drivers/ide/pci/sgiioc4.c
@@ -34,7 +34,7 @@
 #include <linux/mm.h>
 #include <linux/ioport.h>
 #include <linux/blkdev.h>
-#include <linux/ioc4_common.h>
+#include <linux/ioc4.h>
 #include <asm/io.h>
 
 #include <linux/ide.h>
@@ -715,14 +715,34 @@
 };
 
 int
-ioc4_ide_attach_one(struct pci_dev *dev, const struct pci_device_id *id)
+ioc4_ide_attach_one(struct ioc4_driver_data *idd)
 {
-	return pci_init_sgiioc4(dev, &sgiioc4_chipsets[id->driver_data]);
+	return pci_init_sgiioc4(idd->idd_pdev,
+				&sgiioc4_chipsets[idd->idd_pci_id->driver_data]);
 }
 
+static struct ioc4_submodule ioc4_ide_submodule = {
+	.is_name = "IOC4_ide",
+	.is_owner = THIS_MODULE,
+	.is_probe = ioc4_ide_attach_one,
+/*	.is_remove = ioc4_ide_remove_one,	*/
+};
+
+static int __devinit
+ioc4_ide_init(void)
+{
+	return ioc4_register_submodule(&ioc4_ide_submodule);
+}
+
+static void __devexit
+ioc4_ide_exit(void)
+{
+	ioc4_unregister_submodule(&ioc4_ide_submodule);
+}
+
+module_init(ioc4_ide_init);
+module_exit(ioc4_ide_exit);
 
 MODULE_AUTHOR("Aniket Malatpure - Silicon Graphics Inc. (SGI)");
 MODULE_DESCRIPTION("IDE PCI driver module for SGI IOC4 Base-IO Card");
 MODULE_LICENSE("GPL");
-
-EXPORT_SYMBOL(ioc4_ide_attach_one);
diff --git a/drivers/serial/ioc4_serial.c b/drivers/serial/ioc4_serial.c
index ba4e13a..da5f10e 100644
--- a/drivers/serial/ioc4_serial.c
+++ b/drivers/serial/ioc4_serial.c
@@ -20,7 +20,7 @@
 #include <linux/serial_reg.h>
 #include <linux/module.h>
 #include <linux/pci.h>
-#include <linux/ioc4_common.h>
+#include <linux/ioc4.h>
 #include <linux/serial_core.h>
 
 /*
@@ -130,12 +130,19 @@
 				 IOC4_SIO_IR_S3_TX_EXPLICIT)
 
 /* Bitmasks for IOC4_OTHER_IR, IOC4_OTHER_IEC, and IOC4_OTHER_IES  */
-#define IOC4_OTHER_IR_ATA_INT           0x00000001  /* ATAPI intr pass-thru */
-#define IOC4_OTHER_IR_ATA_MEMERR        0x00000002  /* ATAPI DMA PCI error */
-#define IOC4_OTHER_IR_S0_MEMERR         0x00000004  /* Port 0 PCI error */
-#define IOC4_OTHER_IR_S1_MEMERR         0x00000008  /* Port 1 PCI error */
-#define IOC4_OTHER_IR_S2_MEMERR         0x00000010  /* Port 2 PCI error */
-#define IOC4_OTHER_IR_S3_MEMERR         0x00000020  /* Port 3 PCI error */
+#define IOC4_OTHER_IR_ATA_INT		0x00000001  /* ATAPI intr pass-thru */
+#define IOC4_OTHER_IR_ATA_MEMERR	0x00000002  /* ATAPI DMA PCI error */
+#define IOC4_OTHER_IR_S0_MEMERR		0x00000004  /* Port 0 PCI error */
+#define IOC4_OTHER_IR_S1_MEMERR		0x00000008  /* Port 1 PCI error */
+#define IOC4_OTHER_IR_S2_MEMERR		0x00000010  /* Port 2 PCI error */
+#define IOC4_OTHER_IR_S3_MEMERR		0x00000020  /* Port 3 PCI error */
+#define IOC4_OTHER_IR_KBD_INT		0x00000040  /* Keyboard/mouse */
+#define IOC4_OTHER_IR_RESERVED		0x007fff80  /* Reserved */
+#define IOC4_OTHER_IR_RT_INT		0x00800000  /* INT_OUT section output */
+#define IOC4_OTHER_IR_GEN_INT		0xff000000  /* Generic pins */
+
+#define IOC4_OTHER_IR_SER_MEMERR (IOC4_OTHER_IR_S0_MEMERR | IOC4_OTHER_IR_S1_MEMERR | \
+				  IOC4_OTHER_IR_S2_MEMERR | IOC4_OTHER_IR_S3_MEMERR)
 
 /* Bitmasks for IOC4_SIO_CR */
 #define IOC4_SIO_CR_CMD_PULSE_SHIFT              0  /* byte bus strobe shift */
@@ -274,67 +281,22 @@
 #define i4u_dlm u2.dlm
 #define i4u_fcr u3.fcr
 
-/* PCI memory space register map addressed using pci_bar0 */
-struct ioc4_memregs {
-	struct ioc4_mem {
-		/* Miscellaneous IOC4  registers */
-		uint32_t pci_err_addr_l;
-		uint32_t pci_err_addr_h;
-		uint32_t sio_ir;
-		uint32_t other_ir;
+/* Serial port registers used for DMA serial I/O */
+struct ioc4_serial {
+	uint32_t sbbr01_l;
+	uint32_t sbbr01_h;
+	uint32_t sbbr23_l;
+	uint32_t sbbr23_h;
 
-		/* These registers are read-only for general kernel code.  */
-		uint32_t sio_ies_ro;
-		uint32_t other_ies_ro;
-		uint32_t sio_iec_ro;
-		uint32_t other_iec_ro;
-		uint32_t sio_cr;
-		uint32_t misc_fill1;
-		uint32_t int_out;
-		uint32_t misc_fill2;
-		uint32_t gpcr_s;
-		uint32_t gpcr_c;
-		uint32_t gpdr;
-		uint32_t misc_fill3;
-		uint32_t gppr_0;
-		uint32_t gppr_1;
-		uint32_t gppr_2;
-		uint32_t gppr_3;
-		uint32_t gppr_4;
-		uint32_t gppr_5;
-		uint32_t gppr_6;
-		uint32_t gppr_7;
-	} ioc4_mem;
-
-	char misc_fill4[0x100 - 0x5C - 4];
-
-	/* ATA/ATAP registers */
-	uint32_t ata_notused[9];
-	char ata_fill1[0x140 - 0x120 - 4];
-	uint32_t ata_notused1[8];
-	char ata_fill2[0x200 - 0x15C - 4];
-
-	/* Keyboard and mouse registers */
-	uint32_t km_notused[5];;
-	char km_fill1[0x300 - 0x210 - 4];
-
-	/* Serial port registers used for DMA serial I/O */
-	struct ioc4_serial {
-		uint32_t sbbr01_l;
-		uint32_t sbbr01_h;
-		uint32_t sbbr23_l;
-		uint32_t sbbr23_h;
-
-		struct ioc4_serialregs port_0;
-		struct ioc4_serialregs port_1;
-		struct ioc4_serialregs port_2;
-		struct ioc4_serialregs port_3;
-		struct ioc4_uartregs uart_0;
-		struct ioc4_uartregs uart_1;
-		struct ioc4_uartregs uart_2;
-		struct ioc4_uartregs uart_3;
-	} ioc4_serial;
-};
+	struct ioc4_serialregs port_0;
+	struct ioc4_serialregs port_1;
+	struct ioc4_serialregs port_2;
+	struct ioc4_serialregs port_3;
+	struct ioc4_uartregs uart_0;
+	struct ioc4_uartregs uart_1;
+	struct ioc4_uartregs uart_2;
+	struct ioc4_uartregs uart_3;
+} ioc4_serial;
 
 /* UART clock speed */
 #define IOC4_SER_XIN_CLK        IOC4_SER_XIN_CLK_66
@@ -412,8 +374,8 @@
 					| UART_LCR_WLEN7 | UART_LCR_WLEN8)
 #define LCR_MASK_STOP_BITS	(UART_LCR_STOP)
 
-#define PENDING(_p)	(readl(&(_p)->ip_mem->sio_ir) & _p->ip_ienb)
-#define READ_SIO_IR(_p) readl(&(_p)->ip_mem->sio_ir)
+#define PENDING(_p)	(readl(&(_p)->ip_mem->sio_ir.raw) & _p->ip_ienb)
+#define READ_SIO_IR(_p) readl(&(_p)->ip_mem->sio_ir.raw)
 
 /* Default to 4k buffers */
 #ifdef IOC4_1K_BUFFERS
@@ -447,7 +409,7 @@
  */
 #define MAX_IOC4_INTR_ENTS	(8 * sizeof(uint32_t))
 struct ioc4_soft {
-	struct ioc4_mem __iomem *is_ioc4_mem_addr;
+	struct ioc4_misc_regs __iomem *is_ioc4_misc_addr;
 	struct ioc4_serial __iomem *is_ioc4_serial_addr;
 
 	/* Each interrupt type has an entry in the array */
@@ -486,7 +448,7 @@
 	struct ioc4_soft *ip_ioc4_soft;
 
 	/* pci mem addresses */
-	struct ioc4_mem __iomem *ip_mem;
+	struct ioc4_misc_regs __iomem *ip_mem;
 	struct ioc4_serial __iomem *ip_serial;
 	struct ioc4_serialregs __iomem *ip_serial_regs;
 	struct ioc4_uartregs __iomem *ip_uart_regs;
@@ -553,7 +515,7 @@
 	uint32_t intr_dma_error;
 	uint32_t intr_clear;
 	uint32_t intr_all;
-	char rs422_select_pin;
+	int rs422_select_pin;
 };
 
 static struct hooks hooks_array[IOC4_NUM_SERIAL_PORTS] = {
@@ -669,7 +631,7 @@
 static inline void
 write_ireg(struct ioc4_soft *ioc4_soft, uint32_t val, int which, int type)
 {
-	struct ioc4_mem __iomem *mem = ioc4_soft->is_ioc4_mem_addr;
+	struct ioc4_misc_regs __iomem *mem = ioc4_soft->is_ioc4_misc_addr;
 	unsigned long flags;
 
 	spin_lock_irqsave(&ioc4_soft->is_ir_lock, flags);
@@ -678,11 +640,11 @@
 	case IOC4_SIO_INTR_TYPE:
 		switch (which) {
 		case IOC4_W_IES:
-			writel(val, &mem->sio_ies_ro);
+			writel(val, &mem->sio_ies.raw);
 			break;
 
 		case IOC4_W_IEC:
-			writel(val, &mem->sio_iec_ro);
+			writel(val, &mem->sio_iec.raw);
 			break;
 		}
 		break;
@@ -690,11 +652,11 @@
 	case IOC4_OTHER_INTR_TYPE:
 		switch (which) {
 		case IOC4_W_IES:
-			writel(val, &mem->other_ies_ro);
+			writel(val, &mem->other_ies.raw);
 			break;
 
 		case IOC4_W_IEC:
-			writel(val, &mem->other_iec_ro);
+			writel(val, &mem->other_iec.raw);
 			break;
 		}
 		break;
@@ -747,7 +709,8 @@
  */
 static struct ioc4_port *get_ioc4_port(struct uart_port *the_port)
 {
-	struct ioc4_control *control = dev_get_drvdata(the_port->dev);
+	struct ioc4_driver_data *idd = dev_get_drvdata(the_port->dev);
+	struct ioc4_control *control = idd->idd_serial_data;
 	int ii;
 
 	if (control) {
@@ -782,7 +745,7 @@
 static inline uint32_t
 pending_intrs(struct ioc4_soft *soft, int type)
 {
-	struct ioc4_mem __iomem *mem = soft->is_ioc4_mem_addr;
+	struct ioc4_misc_regs __iomem *mem = soft->is_ioc4_misc_addr;
 	unsigned long flag;
 	uint32_t intrs = 0;
 
@@ -793,11 +756,11 @@
 
 	switch (type) {
 	case IOC4_SIO_INTR_TYPE:
-		intrs = readl(&mem->sio_ir) & readl(&mem->sio_ies_ro);
+		intrs = readl(&mem->sio_ir.raw) & readl(&mem->sio_ies.raw);
 		break;
 
 	case IOC4_OTHER_INTR_TYPE:
-		intrs = readl(&mem->other_ir) & readl(&mem->other_ies_ro);
+		intrs = readl(&mem->other_ir.raw) & readl(&mem->other_ies.raw);
 
 		/* Don't process any ATA interrupte */
 		intrs &= ~(IOC4_OTHER_IR_ATA_INT | IOC4_OTHER_IR_ATA_MEMERR);
@@ -826,7 +789,7 @@
 
 	/* Wait until any pending bus activity for this port has ceased */
 	do
-		sio_cr = readl(&port->ip_mem->sio_cr);
+		sio_cr = readl(&port->ip_mem->sio_cr.raw);
 	while (!(sio_cr & IOC4_SIO_CR_SIO_DIAG_IDLE));
 
 	/* Finish reset sequence */
@@ -899,7 +862,7 @@
 	write_ireg(port->ip_ioc4_soft, hooks->intr_clear,
 		       IOC4_W_IEC, IOC4_SIO_INTR_TYPE);
 	port->ip_ienb &= ~hooks->intr_clear;
-	writel(hooks->intr_clear, &port->ip_mem->sio_ir);
+	writel(hooks->intr_clear, &port->ip_mem->sio_ir.raw);
 	return 0;
 }
 
@@ -918,23 +881,23 @@
 	spin_lock_irqsave(&port->ip_lock, flags);
 
 	/* ACK the interrupt */
-	writel(hooks->intr_dma_error, &port->ip_mem->other_ir);
+	writel(hooks->intr_dma_error, &port->ip_mem->other_ir.raw);
 
-	if (readl(&port->ip_mem->pci_err_addr_l) & IOC4_PCI_ERR_ADDR_VLD) {
+	if (readl(&port->ip_mem->pci_err_addr_l.raw) & IOC4_PCI_ERR_ADDR_VLD) {
 		printk(KERN_ERR
 			"PCI error address is 0x%lx, "
 				"master is serial port %c %s\n",
 		     (((uint64_t)readl(&port->ip_mem->pci_err_addr_h)
 							 << 32)
-				| readl(&port->ip_mem->pci_err_addr_l))
+				| readl(&port->ip_mem->pci_err_addr_l.raw))
 					& IOC4_PCI_ERR_ADDR_ADDR_MSK, '1' +
-		     ((char)(readl(&port->ip_mem-> pci_err_addr_l) &
+		     ((char)(readl(&port->ip_mem->pci_err_addr_l.raw) &
 			     IOC4_PCI_ERR_ADDR_MST_NUM_MSK) >> 1),
-		     (readl(&port->ip_mem->pci_err_addr_l)
+		     (readl(&port->ip_mem->pci_err_addr_l.raw)
 				& IOC4_PCI_ERR_ADDR_MST_TYP_MSK)
 				? "RX" : "TX");
 
-		if (readl(&port->ip_mem->pci_err_addr_l)
+		if (readl(&port->ip_mem->pci_err_addr_l.raw)
 						& IOC4_PCI_ERR_ADDR_MUL_ERR) {
 			printk(KERN_ERR
 				"Multiple errors occurred\n");
@@ -1018,26 +981,26 @@
 				"other_ies = 0x%x\n",
 			       (intr_type == IOC4_SIO_INTR_TYPE) ? "sio" :
 			       "other", this_ir,
-			       readl(&soft->is_ioc4_mem_addr->sio_ir),
-			       readl(&soft->is_ioc4_mem_addr->sio_ies_ro),
-			       readl(&soft->is_ioc4_mem_addr->other_ir),
-			       readl(&soft->is_ioc4_mem_addr->other_ies_ro));
+			       readl(&soft->is_ioc4_misc_addr->sio_ir.raw),
+			       readl(&soft->is_ioc4_misc_addr->sio_ies.raw),
+			       readl(&soft->is_ioc4_misc_addr->other_ir.raw),
+			       readl(&soft->is_ioc4_misc_addr->other_ies.raw));
 		}
 	}
 #ifdef DEBUG_INTERRUPTS
 	{
-		struct ioc4_mem __iomem *mem = soft->is_ioc4_mem_addr;
+		struct ioc4_misc_regs __iomem *mem = soft->is_ioc4_misc_addr;
 		spinlock_t *lp = &soft->is_ir_lock;
 		unsigned long flag;
 
 		spin_lock_irqsave(&soft->is_ir_lock, flag);
-		printk ("%s : %d : mem 0x%p sio_ir 0x%x sio_ies_ro 0x%x "
-				"other_ir 0x%x other_ies_ro 0x%x mask 0x%x\n",
+		printk ("%s : %d : mem 0x%p sio_ir 0x%x sio_ies 0x%x "
+				"other_ir 0x%x other_ies 0x%x mask 0x%x\n",
 		     __FUNCTION__, __LINE__,
-		     (void *)mem, readl(&mem->sio_ir),
-		     readl(&mem->sio_ies_ro),
-		     readl(&mem->other_ir),
-		     readl(&mem->other_ies_ro),
+		     (void *)mem, readl(&mem->sio_ir.raw),
+		     readl(&mem->sio_ies.raw),
+		     readl(&mem->other_ir.raw),
+		     readl(&mem->other_ies.raw),
 		     IOC4_OTHER_IR_ATA_INT | IOC4_OTHER_IR_ATA_MEMERR);
 		spin_unlock_irqrestore(&soft->is_ir_lock, flag);
 	}
@@ -1056,7 +1019,7 @@
  */
 static int inline ioc4_attach_local(struct pci_dev *pdev,
 			struct ioc4_control *control,
-			struct ioc4_soft *soft, void __iomem *ioc4_mem,
+			struct ioc4_soft *soft, void __iomem *ioc4_misc,
 			void __iomem *ioc4_serial)
 {
 	struct ioc4_port *port;
@@ -1076,7 +1039,7 @@
 				ioc4_revid, ioc4_revid_min);
 		return -EPERM;
 	}
-	BUG_ON(ioc4_mem == NULL);
+	BUG_ON(ioc4_misc == NULL);
 	BUG_ON(ioc4_serial == NULL);
 
 	/* Create port structures for each port */
@@ -1103,7 +1066,7 @@
 		port->ip_pci_bus_speed = IOC4_SER_XIN_CLK;
 		port->ip_baud = 9600;
 		port->ip_control = control;
-		port->ip_mem = ioc4_mem;
+		port->ip_mem = ioc4_misc;
 		port->ip_serial = ioc4_serial;
 
 		/* point to the right hook */
@@ -1604,14 +1567,12 @@
 	switch (proto) {
 	case PROTO_RS232:
 		/* Clear the appropriate GIO pin */
-		writel(0, (&port->ip_mem->gppr_0 +
-				  hooks->rs422_select_pin));
+		writel(0, (&port->ip_mem->gppr[hooks->rs422_select_pin].raw));
 		break;
 
 	case PROTO_RS422:
 		/* Set the appropriate GIO pin */
-		writel(1, (&port->ip_mem->gppr_0 +
-				  hooks->rs422_select_pin));
+		writel(1, (&port->ip_mem->gppr[hooks->rs422_select_pin].raw));
 		break;
 
 	default:
@@ -1885,7 +1846,7 @@
 		if (sio_ir & hooks->intr_delta_dcd) {
 			/* ACK the interrupt */
 			writel(hooks->intr_delta_dcd,
-				&port->ip_mem->sio_ir);
+				&port->ip_mem->sio_ir.raw);
 
 			shadow = readl(&port->ip_serial_regs->shadow);
 
@@ -1907,7 +1868,7 @@
 		if (sio_ir & hooks->intr_delta_cts) {
 			/* ACK the interrupt */
 			writel(hooks->intr_delta_cts,
-					&port->ip_mem->sio_ir);
+					&port->ip_mem->sio_ir.raw);
 
 			shadow = readl(&port->ip_serial_regs->shadow);
 
@@ -1928,7 +1889,7 @@
 		if (sio_ir & hooks->intr_rx_timer) {
 			/* ACK the interrupt */
 			writel(hooks->intr_rx_timer,
-				&port->ip_mem->sio_ir);
+				&port->ip_mem->sio_ir.raw);
 
 			if ((port->ip_notify & N_DATA_READY)
 					&& (port->ip_port)) {
@@ -1974,7 +1935,7 @@
 
 			/* ACK the interrupt */
 			writel(hooks->intr_tx_explicit,
-					&port->ip_mem->sio_ir);
+					&port->ip_mem->sio_ir.raw);
 
 			if (port->ip_notify & N_OUTPUT_LOWAT)
 				ioc4_cb_output_lowat(port);
@@ -2634,7 +2595,8 @@
 {
 	struct ioc4_port *port;
 	struct uart_port *the_port;
-	struct ioc4_control *control = pci_get_drvdata(pdev);
+	struct ioc4_driver_data *idd = pci_get_drvdata(pdev);
+	struct ioc4_control *control = idd->idd_serial_data;
 	int ii;
 
 	DPRINT_CONFIG(("%s: attach pdev 0x%p - control 0x%p\n",
@@ -2680,55 +2642,29 @@
 
 /**
  * ioc4_serial_attach_one - register attach function
- *		called per card found from ioc4_serial_detect as part
- *		of module_init().
- * @pdev: handle for this card
- * @pci_id: pci id for this card
+ *		called per card found from IOC4 master module.
+ * @idd: Master module data for this IOC4
  */
 int
-ioc4_serial_attach_one(struct pci_dev *pdev, const struct pci_device_id *pci_id)
+ioc4_serial_attach_one(struct ioc4_driver_data *idd)
 {
-	struct ioc4_mem __iomem *mem;
-	unsigned long tmp_addr, tmp_addr1;
+	unsigned long tmp_addr1;
 	struct ioc4_serial __iomem *serial;
 	struct ioc4_soft *soft;
 	struct ioc4_control *control;
-	int tmp, ret = 0;
+	int ret = 0;
 
 
-	DPRINT_CONFIG(("%s (0x%p, 0x%p)\n", __FUNCTION__, pdev, pci_id));
-
-	/* Map in the ioc4 memory */
-	tmp_addr = pci_resource_start(pdev, 0);
-	if (!tmp_addr) {
-		printk(KERN_WARNING
-			 "ioc4 (%p) : unable to get PIO mapping for "
-				"MEM space\n", (void *)pdev);
-		return -ENODEV;
-	}
-	if (!request_region(tmp_addr, sizeof(struct ioc4_mem), "sioc4_mem")) {
-		printk(KERN_ALERT
-			"ioc4 (%p): unable to get request region for "
-			"MEM space\n", (void *)pdev);
-		return -ENODEV;
-	}
-	mem = ioremap(tmp_addr, sizeof(struct ioc4_mem));
-	if (!mem) {
-		printk(KERN_WARNING
-			 "ioc4 (%p) : unable to remap ioc4 memory\n",
-				(void *)pdev);
-		ret = -ENODEV;
-		goto out1;
-	}
+	DPRINT_CONFIG(("%s (0x%p, 0x%p)\n", __FUNCTION__, idd->idd_pdev, idd->idd_pci_id));
 
 	/* request serial registers */
-	tmp_addr1 = pci_resource_start(pdev, 0) + IOC4_SERIAL_OFFSET;
+	tmp_addr1 = idd->idd_bar0 + IOC4_SERIAL_OFFSET;
 
 	if (!request_region(tmp_addr1, sizeof(struct ioc4_serial),
 					"sioc4_uart")) {
 		printk(KERN_WARNING
 			"ioc4 (%p): unable to get request region for "
-				"uart space\n", (void *)pdev);
+				"uart space\n", (void *)idd->idd_pdev);
 		ret = -ENODEV;
 		goto out1;
 	}
@@ -2736,12 +2672,12 @@
 	if (!serial) {
 		printk(KERN_WARNING
 			 "ioc4 (%p) : unable to remap ioc4 serial register\n",
-				(void *)pdev);
+				(void *)idd->idd_pdev);
 		ret = -ENODEV;
 		goto out2;
 	}
 	DPRINT_CONFIG(("%s : mem 0x%p, serial 0x%p\n",
-				__FUNCTION__, (void *)mem, (void *)serial));
+				__FUNCTION__, (void *)idd->idd_misc_regs, (void *)serial));
 
 	/* Get memory for the new card */
 	control = kmalloc(sizeof(struct ioc4_control) * IOC4_NUM_SERIAL_PORTS,
@@ -2754,59 +2690,57 @@
 		goto out2;
 	}
 	memset(control, 0, sizeof(struct ioc4_control));
-	pci_set_drvdata(pdev, control);
+	idd->idd_serial_data = control;
 
 	/* Allocate the soft structure */
 	soft = kmalloc(sizeof(struct ioc4_soft), GFP_KERNEL);
 	if (!soft) {
 		printk(KERN_WARNING
 		       "ioc4 (%p): unable to get memory for the soft struct\n",
-		       (void *)pdev);
+		       (void *)idd->idd_pdev);
 		ret = -ENOMEM;
 		goto out3;
 	}
 	memset(soft, 0, sizeof(struct ioc4_soft));
 
 	spin_lock_init(&soft->is_ir_lock);
-	soft->is_ioc4_mem_addr = mem;
+	soft->is_ioc4_misc_addr = idd->idd_misc_regs;
 	soft->is_ioc4_serial_addr = serial;
 
 	/* Init the IOC4 */
-	pci_read_config_dword(pdev, PCI_COMMAND, &tmp);
-	pci_write_config_dword(pdev, PCI_COMMAND,
-			       tmp | PCI_COMMAND_PARITY | PCI_COMMAND_SERR);
-
-	writel(0xf << IOC4_SIO_CR_CMD_PULSE_SHIFT, &mem->sio_cr);
+	writel(0xf << IOC4_SIO_CR_CMD_PULSE_SHIFT,
+	       &idd->idd_misc_regs->sio_cr.raw);
 
 	/* Enable serial port mode select generic PIO pins as outputs */
 	writel(IOC4_GPCR_UART0_MODESEL | IOC4_GPCR_UART1_MODESEL
 		| IOC4_GPCR_UART2_MODESEL | IOC4_GPCR_UART3_MODESEL,
-		&mem->gpcr_s);
+		&idd->idd_misc_regs->gpcr_s.raw);
 
-	/* Clear and disable all interrupts */
+	/* Clear and disable all serial interrupts */
 	write_ireg(soft, ~0, IOC4_W_IEC, IOC4_SIO_INTR_TYPE);
-	writel(~0, &mem->sio_ir);
-	write_ireg(soft, ~(IOC4_OTHER_IR_ATA_INT | IOC4_OTHER_IR_ATA_MEMERR),
-			IOC4_W_IEC, IOC4_OTHER_INTR_TYPE);
-	writel(~(IOC4_OTHER_IR_ATA_MEMERR | IOC4_OTHER_IR_ATA_MEMERR),
-					&mem->other_ir);
+	writel(~0, &idd->idd_misc_regs->sio_ir.raw);
+	write_ireg(soft, IOC4_OTHER_IR_SER_MEMERR, IOC4_W_IEC,
+		   IOC4_OTHER_INTR_TYPE);
+	writel(IOC4_OTHER_IR_SER_MEMERR, &idd->idd_misc_regs->other_ir.raw);
 	control->ic_soft = soft;
-	if (!request_irq(pdev->irq, ioc4_intr, SA_SHIRQ,
+
+	/* Hook up interrupt handler */
+	if (!request_irq(idd->idd_pdev->irq, ioc4_intr, SA_SHIRQ,
 				"sgi-ioc4serial", (void *)soft)) {
-		control->ic_irq = pdev->irq;
+		control->ic_irq = idd->idd_pdev->irq;
 	} else {
 		printk(KERN_WARNING
 		    "%s : request_irq fails for IRQ 0x%x\n ",
-			__FUNCTION__, pdev->irq);
+			__FUNCTION__, idd->idd_pdev->irq);
 	}
-	if ((ret = ioc4_attach_local(pdev, control, soft,
-				soft->is_ioc4_mem_addr,
+	if ((ret = ioc4_attach_local(idd->idd_pdev, control, soft,
+				soft->is_ioc4_misc_addr,
 				soft->is_ioc4_serial_addr)))
 		goto out4;
 
 	/* register port with the serial core */
 
-	if ((ret = ioc4_serial_core_attach(pdev)))
+	if ((ret = ioc4_serial_core_attach(idd->idd_pdev)))
 		goto out4;
 
 	return ret;
@@ -2819,7 +2753,6 @@
 out2:
 	release_region(tmp_addr1, sizeof(struct ioc4_serial));
 out1:
-	release_region(tmp_addr, sizeof(struct ioc4_mem));
 
 	return ret;
 }
@@ -2828,11 +2761,10 @@
 /**
  * ioc4_serial_remove_one - detach function
  *
- * @pdev: handle for this card
+ * @idd: IOC4 master module data for this IOC4
  */
 
-#if 0
-void ioc4_serial_remove_one(struct pci_dev *pdev)
+int ioc4_serial_remove_one(struct ioc4_driver_data *idd)
 {
 	int ii;
 	struct ioc4_control *control;
@@ -2840,7 +2772,7 @@
 	struct ioc4_port *port;
 	struct ioc4_soft *soft;
 
-	control = pci_get_drvdata(pdev);
+	control = idd->idd_serial_data;
 
 	for (ii = 0; ii < IOC4_NUM_SERIAL_PORTS; ii++) {
 		the_port = &control->ic_port[ii].icp_uart_port;
@@ -2867,10 +2799,17 @@
 		kfree(soft);
 	}
 	kfree(control);
-	pci_set_drvdata(pdev, NULL);
-	uart_unregister_driver(&ioc4_uart);
+	idd->idd_serial_data = NULL;
+
+	return 0;
 }
-#endif
+
+static struct ioc4_submodule ioc4_serial_submodule = {
+	.is_name = "IOC4_serial",
+	.is_owner = THIS_MODULE,
+	.is_probe = ioc4_serial_attach_one,
+	.is_remove = ioc4_serial_remove_one,
+};
 
 /**
  * ioc4_serial_init - module init
@@ -2886,12 +2825,20 @@
 			__FUNCTION__);
 		return ret;
 	}
-	return 0;
+
+	/* register with IOC4 main module */
+	return ioc4_register_submodule(&ioc4_serial_submodule);
 }
 
+static void __devexit ioc4_serial_exit(void)
+{
+	ioc4_unregister_submodule(&ioc4_serial_submodule);
+	uart_unregister_driver(&ioc4_uart);
+}
+
+module_init(ioc4_serial_init);
+module_exit(ioc4_serial_exit);
+
 MODULE_AUTHOR("Pat Gefre - Silicon Graphics Inc. (SGI) <pfg@sgi.com>");
 MODULE_DESCRIPTION("Serial PCI driver module for SGI IOC4 Base-IO Card");
 MODULE_LICENSE("GPL");
-
-EXPORT_SYMBOL(ioc4_serial_init);
-EXPORT_SYMBOL(ioc4_serial_attach_one);
diff --git a/drivers/sn/ioc4.c b/drivers/sn/ioc4.c
index d9e4ee2..70862d7 100644
--- a/drivers/sn/ioc4.c
+++ b/drivers/sn/ioc4.c
@@ -6,60 +6,294 @@
  * Copyright (C) 2005 Silicon Graphics, Inc.  All Rights Reserved.
  */
 
-/*
- * This file contains a shim driver for the IOC4 IDE and serial drivers.
+/* This file contains the master driver module for use by SGI IOC4 subdrivers.
+ *
+ * It allocates any resources shared between multiple subdevices, and
+ * provides accessor functions (where needed) and the like for those
+ * resources.  It also provides a mechanism for the subdevice modules
+ * to support loading and unloading.
+ *
+ * Non-shared resources (e.g. external interrupt A_INT_OUT register page
+ * alias, serial port and UART registers) are handled by the subdevice
+ * modules themselves.
+ *
+ * This is all necessary because IOC4 is not implemented as a multi-function
+ * PCI device, but an amalgamation of disparate registers for several
+ * types of device (ATA, serial, external interrupts).  The normal
+ * resource management in the kernel doesn't have quite the right interfaces
+ * to handle this situation (e.g. multiple modules can't claim the same
+ * PCI ID), thus this IOC4 master module.
  */
 
 #include <linux/errno.h>
 #include <linux/module.h>
 #include <linux/pci.h>
-#include <linux/ioc4_common.h>
-#include <linux/ide.h>
+#include <linux/ioc4.h>
+#include <linux/rwsem.h>
 
+/************************
+ * Submodule management *
+ ************************/
 
-static int __devinit
-ioc4_probe_one(struct pci_dev *pdev, const struct pci_device_id *pci_id)
+static LIST_HEAD(ioc4_devices);
+static DECLARE_RWSEM(ioc4_devices_rwsem);
+
+static LIST_HEAD(ioc4_submodules);
+static DECLARE_RWSEM(ioc4_submodules_rwsem);
+
+/* Register an IOC4 submodule */
+int
+ioc4_register_submodule(struct ioc4_submodule *is)
 {
+	struct ioc4_driver_data *idd;
+
+	down_write(&ioc4_submodules_rwsem);
+	list_add(&is->is_list, &ioc4_submodules);
+	up_write(&ioc4_submodules_rwsem);
+
+	/* Initialize submodule for each IOC4 */
+	if (!is->is_probe)
+		return 0;
+
+	down_read(&ioc4_devices_rwsem);
+	list_for_each_entry(idd, &ioc4_devices, idd_list) {
+		if (is->is_probe(idd)) {
+			printk(KERN_WARNING
+			       "%s: IOC4 submodule %s probe failed "
+			       "for pci_dev %s",
+			       __FUNCTION__, module_name(is->is_owner),
+			       pci_name(idd->idd_pdev));
+		}
+	}
+	up_read(&ioc4_devices_rwsem);
+
+	return 0;
+}
+
+/* Unregister an IOC4 submodule */
+void
+ioc4_unregister_submodule(struct ioc4_submodule *is)
+{
+	struct ioc4_driver_data *idd;
+
+	down_write(&ioc4_submodules_rwsem);
+	list_del(&is->is_list);
+	up_write(&ioc4_submodules_rwsem);
+
+	/* Remove submodule for each IOC4 */
+	if (!is->is_remove)
+		return;
+
+	down_read(&ioc4_devices_rwsem);
+	list_for_each_entry(idd, &ioc4_devices, idd_list) {
+		if (is->is_remove(idd)) {
+			printk(KERN_WARNING
+			       "%s: IOC4 submodule %s remove failed "
+			       "for pci_dev %s.\n",
+			       __FUNCTION__, module_name(is->is_owner),
+			       pci_name(idd->idd_pdev));
+		}
+	}
+	up_read(&ioc4_devices_rwsem);
+}
+
+/*********************
+ * Device management *
+ *********************/
+
+/* Adds a new instance of an IOC4 card */
+static int
+ioc4_probe(struct pci_dev *pdev, const struct pci_device_id *pci_id)
+{
+	struct ioc4_driver_data *idd;
+	struct ioc4_submodule *is;
+	uint32_t pcmd;
 	int ret;
 
+	/* Enable IOC4 and take ownership of it */
 	if ((ret = pci_enable_device(pdev))) {
 		printk(KERN_WARNING
-			 "%s: Failed to enable device with "
-				"pci_dev 0x%p... returning\n",
-				__FUNCTION__, (void *)pdev);
-		return ret;
+		       "%s: Failed to enable IOC4 device for pci_dev %s.\n",
+		       __FUNCTION__, pci_name(pdev));
+		goto out;
 	}
 	pci_set_master(pdev);
 
-	/* attach each sub-device */
-	ret = ioc4_ide_attach_one(pdev, pci_id);
-	if (ret)
-		return ret;
-	return ioc4_serial_attach_one(pdev, pci_id);
+	/* Set up per-IOC4 data */
+	idd = kmalloc(sizeof(struct ioc4_driver_data), GFP_KERNEL);
+	if (!idd) {
+		printk(KERN_WARNING
+		       "%s: Failed to allocate IOC4 data for pci_dev %s.\n",
+		       __FUNCTION__, pci_name(pdev));
+		ret = -ENODEV;
+		goto out_idd;
+	}
+	idd->idd_pdev = pdev;
+	idd->idd_pci_id = pci_id;
+
+	/* Map IOC4 misc registers.  These are shared between subdevices
+	 * so the main IOC4 module manages them.
+	 */
+	idd->idd_bar0 = pci_resource_start(idd->idd_pdev, 0);
+	if (!idd->idd_bar0) {
+		printk(KERN_WARNING
+		       "%s: Unable to find IOC4 misc resource "
+		       "for pci_dev %s.\n",
+		       __FUNCTION__, pci_name(idd->idd_pdev));
+		ret = -ENODEV;
+		goto out_pci;
+	}
+	if (!request_region(idd->idd_bar0, sizeof(struct ioc4_misc_regs),
+			    "ioc4_misc")) {
+		printk(KERN_WARNING
+		       "%s: Unable to request IOC4 misc region "
+		       "for pci_dev %s.\n",
+		       __FUNCTION__, pci_name(idd->idd_pdev));
+		ret = -ENODEV;
+		goto out_pci;
+	}
+	idd->idd_misc_regs = ioremap(idd->idd_bar0,
+				     sizeof(struct ioc4_misc_regs));
+	if (!idd->idd_misc_regs) {
+		printk(KERN_WARNING
+		       "%s: Unable to remap IOC4 misc region "
+		       "for pci_dev %s.\n",
+		       __FUNCTION__, pci_name(idd->idd_pdev));
+		ret = -ENODEV;
+		goto out_misc_region;
+	}
+
+	/* Failsafe portion of per-IOC4 initialization */
+
+	/* Initialize IOC4 */
+	pci_read_config_dword(idd->idd_pdev, PCI_COMMAND, &pcmd);
+	pci_write_config_dword(idd->idd_pdev, PCI_COMMAND,
+			       pcmd | PCI_COMMAND_PARITY | PCI_COMMAND_SERR);
+
+	/* Disable/clear all interrupts.  Need to do this here lest
+	 * one submodule request the shared IOC4 IRQ, but interrupt
+	 * is generated by a different subdevice.
+	 */
+	/* Disable */
+	writel(~0, &idd->idd_misc_regs->other_iec.raw);
+	writel(~0, &idd->idd_misc_regs->sio_iec);
+	/* Clear (i.e. acknowledge) */
+	writel(~0, &idd->idd_misc_regs->other_ir.raw);
+	writel(~0, &idd->idd_misc_regs->sio_ir);
+
+	/* Track PCI-device specific data */
+	idd->idd_serial_data = NULL;
+	pci_set_drvdata(idd->idd_pdev, idd);
+	down_write(&ioc4_devices_rwsem);
+	list_add(&idd->idd_list, &ioc4_devices);
+	up_write(&ioc4_devices_rwsem);
+
+	/* Add this IOC4 to all submodules */
+	down_read(&ioc4_submodules_rwsem);
+	list_for_each_entry(is, &ioc4_submodules, is_list) {
+		if (is->is_probe && is->is_probe(idd)) {
+			printk(KERN_WARNING
+			       "%s: IOC4 submodule 0x%s probe failed "
+			       "for pci_dev %s.\n",
+			       __FUNCTION__, module_name(is->is_owner),
+			       pci_name(idd->idd_pdev));
+		}
+	}
+	up_read(&ioc4_submodules_rwsem);
+
+	return 0;
+
+out_misc_region:
+	release_region(idd->idd_bar0, sizeof(struct ioc4_misc_regs));
+out_pci:
+	kfree(idd);
+out_idd:
+	pci_disable_device(pdev);
+out:
+	return ret;
 }
 
-/* pci device struct */
-static struct pci_device_id ioc4_s_id_table[] = {
+/* Removes a particular instance of an IOC4 card. */
+static void
+ioc4_remove(struct pci_dev *pdev)
+{
+	struct ioc4_submodule *is;
+	struct ioc4_driver_data *idd;
+
+	idd = pci_get_drvdata(pdev);
+
+	/* Remove this IOC4 from all submodules */
+	down_read(&ioc4_submodules_rwsem);
+	list_for_each_entry(is, &ioc4_submodules, is_list) {
+		if (is->is_remove && is->is_remove(idd)) {
+			printk(KERN_WARNING
+			       "%s: IOC4 submodule 0x%s remove failed "
+			       "for pci_dev %s.\n",
+			       __FUNCTION__, module_name(is->is_owner),
+			       pci_name(idd->idd_pdev));
+		}
+	}
+	up_read(&ioc4_submodules_rwsem);
+
+	/* Release resources */
+	iounmap(idd->idd_misc_regs);
+	if (!idd->idd_bar0) {
+		printk(KERN_WARNING
+		       "%s: Unable to get IOC4 misc mapping for pci_dev %s. "
+		       "Device removal may be incomplete.\n",
+		       __FUNCTION__, pci_name(idd->idd_pdev));
+	}
+	release_region(idd->idd_bar0, sizeof(struct ioc4_misc_regs));
+
+	/* Disable IOC4 and relinquish */
+	pci_disable_device(pdev);
+
+	/* Remove and free driver data */
+	down_write(&ioc4_devices_rwsem);
+	list_del(&idd->idd_list);
+	up_write(&ioc4_devices_rwsem);
+	kfree(idd);
+}
+
+static struct pci_device_id ioc4_id_table[] = {
 	{PCI_VENDOR_ID_SGI, PCI_DEVICE_ID_SGI_IOC4, PCI_ANY_ID,
 	 PCI_ANY_ID, 0x0b4000, 0xFFFFFF},
 	{0}
 };
-MODULE_DEVICE_TABLE(pci, ioc4_s_id_table);
 
-static struct pci_driver __devinitdata ioc4_s_driver = {
-	.name	= "IOC4",
-	.id_table = ioc4_s_id_table,
-	.probe	= ioc4_probe_one,
+static struct pci_driver __devinitdata ioc4_driver = {
+	.name = "IOC4",
+	.id_table = ioc4_id_table,
+	.probe = ioc4_probe,
+	.remove = ioc4_remove,
 };
 
-static int __devinit ioc4_detect(void)
+MODULE_DEVICE_TABLE(pci, ioc4_id_table);
+
+/*********************
+ * Module management *
+ *********************/
+
+/* Module load */
+static int __devinit
+ioc4_init(void)
 {
-	ioc4_serial_init();
-
-	return pci_register_driver(&ioc4_s_driver);
+	return pci_register_driver(&ioc4_driver);
 }
-module_init(ioc4_detect);
 
-MODULE_AUTHOR("Pat Gefre - Silicon Graphics Inc. (SGI) <pfg@sgi.com>");
-MODULE_DESCRIPTION("PCI driver module for SGI IOC4 Base-IO Card");
+/* Module unload */
+static void __devexit
+ioc4_exit(void)
+{
+	pci_unregister_driver(&ioc4_driver);
+}
+
+module_init(ioc4_init);
+module_exit(ioc4_exit);
+
+MODULE_AUTHOR("Brent Casavant - Silicon Graphics, Inc. <bcasavan@sgi.com>");
+MODULE_DESCRIPTION("PCI driver master module for SGI IOC4 Base-IO Card");
 MODULE_LICENSE("GPL");
+
+EXPORT_SYMBOL(ioc4_register_submodule);
+EXPORT_SYMBOL(ioc4_unregister_submodule);
diff --git a/include/linux/ioc4.h b/include/linux/ioc4.h
new file mode 100644
index 0000000..729bfa4
--- /dev/null
+++ b/include/linux/ioc4.h
@@ -0,0 +1,156 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 2005 Silicon Graphics, Inc.  All Rights Reserved.
+ */
+
+#ifndef _LINUX_IOC4_H
+#define _LINUX_IOC4_H
+
+#include <linux/interrupt.h>
+
+/***********************************
+ * Structures needed by subdrivers *
+ ***********************************/
+
+/* This structure fully describes the IOC4 miscellaneous registers which
+ * appear at bar[0]+0x00000 through bar[0]+0x0005c.  The corresponding
+ * PCI resource is managed by the main IOC4 driver because it contains
+ * registers of interest to many different IOC4 subdrivers.
+ */
+struct ioc4_misc_regs {
+	/* Miscellaneous IOC4 registers */
+	union ioc4_pci_err_addr_l {
+		uint32_t raw;
+		struct {
+			uint32_t valid:1;	/* Address captured */
+			uint32_t master_id:4;	/* Unit causing error
+						 * 0/1: Serial port 0 TX/RX
+						 * 2/3: Serial port 1 TX/RX
+						 * 4/5: Serial port 2 TX/RX
+						 * 6/7: Serial port 3 TX/RX
+						 * 8: ATA/ATAPI
+						 * 9-15: Undefined
+						 */
+			uint32_t mul_err:1;	/* Multiple errors occurred */
+			uint32_t addr:26;	/* Bits 31-6 of error addr */
+		} fields;
+	} pci_err_addr_l;
+	uint32_t pci_err_addr_h;	/* Bits 63-32 of error addr */
+	union ioc4_sio_int {
+		uint32_t raw;
+		struct {
+			uint8_t tx_mt:1;	/* TX ring buffer empty */
+			uint8_t rx_full:1;	/* RX ring buffer full */
+			uint8_t rx_high:1;	/* RX high-water exceeded */
+			uint8_t rx_timer:1;	/* RX timer has triggered */
+			uint8_t delta_dcd:1;	/* DELTA_DCD seen */
+			uint8_t delta_cts:1;	/* DELTA_CTS seen */
+			uint8_t intr_pass:1;	/* Interrupt pass-through */
+			uint8_t tx_explicit:1;	/* TX, MCW, or delay complete */
+		} fields[4];
+	} sio_ir;		/* Serial interrupt state */
+	union ioc4_other_int {
+		uint32_t raw;
+		struct {
+			uint32_t ata_int:1;	/* ATA port passthru */
+			uint32_t ata_memerr:1;	/* ATA halted by mem error */
+			uint32_t memerr:4;	/* Serial halted by mem err */
+			uint32_t kbd_int:1;	/* kbd/mouse intr asserted */
+			uint32_t reserved:16;	/* zero */
+			uint32_t rt_int:1;	/* INT_OUT section latch */
+			uint32_t gen_int:8;	/* Intr. from generic pins */
+		} fields;
+	} other_ir;		/* Other interrupt state */
+	union ioc4_sio_int sio_ies;	/* Serial interrupt enable set */
+	union ioc4_other_int other_ies;	/* Other interrupt enable set */
+	union ioc4_sio_int sio_iec;	/* Serial interrupt enable clear */
+	union ioc4_other_int other_iec;	/* Other interrupt enable clear */
+	union ioc4_sio_cr {
+		uint32_t raw;
+		struct {
+			uint32_t cmd_pulse:4;	/* Bytebus strobe width */
+			uint32_t arb_diag:3;	/* PCI bus requester */
+			uint32_t sio_diag_idle:1;	/* Active ser req? */
+			uint32_t ata_diag_idle:1;	/* Active ATA req? */
+			uint32_t ata_diag_active:1;	/* ATA req is winner */
+			uint32_t reserved:22;	/* zero */
+		} fields;
+	} sio_cr;
+	uint32_t unused1;
+	union ioc4_int_out {
+		uint32_t raw;
+		struct {
+			uint32_t count:16;	/* Period control */
+			uint32_t mode:3;	/* Output signal shape */
+			uint32_t reserved:11;	/* zero */
+			uint32_t diag:1;	/* Timebase control */
+			uint32_t int_out:1;	/* Current value */
+		} fields;
+	} int_out;		/* External interrupt output control */
+	uint32_t unused2;
+	union ioc4_gpcr {
+		uint32_t raw;
+		struct {
+			uint32_t dir:8;	/* Pin direction */
+			uint32_t edge:8;	/* Edge/level mode */
+			uint32_t reserved1:4;	/* zero */
+			uint32_t int_out_en:1;	/* INT_OUT enable */
+			uint32_t reserved2:11;	/* zero */
+		} fields;
+	} gpcr_s;		/* Generic PIO control set */
+	union ioc4_gpcr gpcr_c;	/* Generic PIO control clear */
+	union ioc4_gpdr {
+		uint32_t raw;
+		struct {
+			uint32_t gen_pin:8;	/* State of pins */
+			uint32_t reserved:24;
+		} fields;
+	} gpdr;			/* Generic PIO data */
+	uint32_t unused3;
+	union ioc4_gppr {
+		uint32_t raw;
+		struct {
+			uint32_t gen_pin:1;	/* Single pin state */
+			uint32_t reserved:31;
+		} fields;
+	} gppr[8];		/* Generic PIO pins */
+};
+
+/* One of these per IOC4
+ *
+ * The idd_serial_data field is present here, even though it's used
+ * solely by the serial subdriver, because the main IOC4 module
+ * properly owns pci_{get,set}_drvdata functionality.  This field
+ * allows that subdriver to stash its own drvdata somewhere.
+ */
+struct ioc4_driver_data {
+	struct list_head idd_list;
+	unsigned long idd_bar0;
+	struct pci_dev *idd_pdev;
+	const struct pci_device_id *idd_pci_id;
+	struct __iomem ioc4_misc_regs *idd_misc_regs;
+	void *idd_serial_data;
+};
+
+/* One per submodule */
+struct ioc4_submodule {
+	struct list_head is_list;
+	char *is_name;
+	struct module *is_owner;
+	int (*is_probe) (struct ioc4_driver_data *);
+	int (*is_remove) (struct ioc4_driver_data *);
+};
+
+#define IOC4_NUM_CARDS		8	/* max cards per partition */
+
+/**********************************
+ * Functions needed by submodules *
+ **********************************/
+
+extern int ioc4_register_submodule(struct ioc4_submodule *);
+extern void ioc4_unregister_submodule(struct ioc4_submodule *);
+
+#endif				/* _LINUX_IOC4_H */
diff --git a/include/linux/ioc4_common.h b/include/linux/ioc4_common.h
deleted file mode 100644
index b03bcc4..0000000
--- a/include/linux/ioc4_common.h
+++ /dev/null
@@ -1,21 +0,0 @@
-/*
- * This file is subject to the terms and conditions of the GNU General Public
- * License.  See the file "COPYING" in the main directory of this archive
- * for more details.
- *
- * Copyright (c) 2005 Silicon Graphics, Inc.  All Rights Reserved.
- */
-
-#ifndef _LINUX_IOC4_COMMON_H
-#define _LINUX_IOC4_COMMON_H
-
-/* prototypes */
-
-int ioc4_serial_init(void);
-
-int ioc4_serial_attach_one(struct pci_dev *pdev, const struct
-				pci_device_id *pci_id);
-int ioc4_ide_attach_one(struct pci_dev *pdev, const struct
-				pci_device_id *pci_id);
-
-#endif	/* _LINUX_IOC4_COMMON_H */