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-rw-r--r--drivers/sh/Makefile4
-rw-r--r--drivers/sh/maple/Makefile3
-rw-r--r--drivers/sh/maple/maple.c735
3 files changed, 740 insertions, 2 deletions
diff --git a/drivers/sh/Makefile b/drivers/sh/Makefile
index 8a143894e33..a96f4a8cfeb 100644
--- a/drivers/sh/Makefile
+++ b/drivers/sh/Makefile
@@ -2,5 +2,5 @@
# Makefile for the SuperH specific drivers.
#
-obj-$(CONFIG_SUPERHYWAY) += superhyway/
-
+obj-$(CONFIG_SUPERHYWAY) += superhyway/
+obj-$(CONFIG_MAPLE) += maple/
diff --git a/drivers/sh/maple/Makefile b/drivers/sh/maple/Makefile
new file mode 100644
index 00000000000..65dfeeb610e
--- /dev/null
+++ b/drivers/sh/maple/Makefile
@@ -0,0 +1,3 @@
+# Makefile for Maple Bus
+
+obj-$(CONFIG_MAPLE) := maple.o
diff --git a/drivers/sh/maple/maple.c b/drivers/sh/maple/maple.c
new file mode 100644
index 00000000000..161d1021b7e
--- /dev/null
+++ b/drivers/sh/maple/maple.c
@@ -0,0 +1,735 @@
+/*
+ * Core maple bus functionality
+ *
+ * Copyright (C) 2007 Adrian McMenamin
+ *
+ * Based on 2.4 code by:
+ *
+ * Copyright (C) 2000-2001 YAEGASHI Takeshi
+ * Copyright (C) 2001 M. R. Brown
+ * Copyright (C) 2001 Paul Mundt
+ *
+ * and others.
+ *
+ * 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.
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/list.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/maple.h>
+#include <linux/dma-mapping.h>
+#include <asm/cacheflush.h>
+#include <asm/dma.h>
+#include <asm/io.h>
+#include <asm/mach/dma.h>
+#include <asm/mach/sysasic.h>
+#include <asm/mach/maple.h>
+
+MODULE_AUTHOR("Yaegshi Takeshi, Paul Mundt, M.R. Brown, Adrian McMenamin");
+MODULE_DESCRIPTION("Maple bus driver for Dreamcast");
+MODULE_LICENSE("GPL v2");
+MODULE_SUPPORTED_DEVICE("{{SEGA, Dreamcast/Maple}}");
+
+static void maple_dma_handler(struct work_struct *work);
+static void maple_vblank_handler(struct work_struct *work);
+
+static DECLARE_WORK(maple_dma_process, maple_dma_handler);
+static DECLARE_WORK(maple_vblank_process, maple_vblank_handler);
+
+static LIST_HEAD(maple_waitq);
+static LIST_HEAD(maple_sentq);
+
+static DEFINE_MUTEX(maple_list_lock);
+
+static struct maple_driver maple_dummy_driver;
+static struct device maple_bus;
+static int subdevice_map[MAPLE_PORTS];
+static unsigned long *maple_sendbuf, *maple_sendptr, *maple_lastptr;
+static unsigned long maple_pnp_time;
+static int started, scanning, liststatus;
+static struct kmem_cache *maple_queue_cache;
+
+struct maple_device_specify {
+ int port;
+ int unit;
+};
+
+/**
+ * maple_driver_register - register a device driver
+ * automatically makes the driver bus a maple bus
+ * @drv: the driver to be registered
+ */
+int maple_driver_register(struct device_driver *drv)
+{
+ if (!drv)
+ return -EINVAL;
+ drv->bus = &maple_bus_type;
+ return driver_register(drv);
+}
+EXPORT_SYMBOL_GPL(maple_driver_register);
+
+/* set hardware registers to enable next round of dma */
+static void maplebus_dma_reset(void)
+{
+ ctrl_outl(MAPLE_MAGIC, MAPLE_RESET);
+ /* set trig type to 0 for software trigger, 1 for hardware (VBLANK) */
+ ctrl_outl(1, MAPLE_TRIGTYPE);
+ ctrl_outl(MAPLE_2MBPS | MAPLE_TIMEOUT(50000), MAPLE_SPEED);
+ ctrl_outl(PHYSADDR(maple_sendbuf), MAPLE_DMAADDR);
+ ctrl_outl(1, MAPLE_ENABLE);
+}
+
+/**
+ * maple_getcond_callback - setup handling MAPLE_COMMAND_GETCOND
+ * @dev: device responding
+ * @callback: handler callback
+ * @interval: interval in jiffies between callbacks
+ * @function: the function code for the device
+ */
+void maple_getcond_callback(struct maple_device *dev,
+ void (*callback) (struct mapleq * mq),
+ unsigned long interval, unsigned long function)
+{
+ dev->callback = callback;
+ dev->interval = interval;
+ dev->function = cpu_to_be32(function);
+ dev->when = jiffies;
+}
+EXPORT_SYMBOL_GPL(maple_getcond_callback);
+
+static int maple_dma_done(void)
+{
+ return (ctrl_inl(MAPLE_STATE) & 1) == 0;
+}
+
+static void maple_release_device(struct device *dev)
+{
+ if (dev->type) {
+ kfree(dev->type->name);
+ kfree(dev->type);
+ }
+}
+
+/**
+ * maple_add_packet - add a single instruction to the queue
+ * @mq: instruction to add to waiting queue
+ */
+void maple_add_packet(struct mapleq *mq)
+{
+ mutex_lock(&maple_list_lock);
+ list_add(&mq->list, &maple_waitq);
+ mutex_unlock(&maple_list_lock);
+}
+EXPORT_SYMBOL_GPL(maple_add_packet);
+
+static struct mapleq *maple_allocq(struct maple_device *dev)
+{
+ struct mapleq *mq;
+
+ mq = kmalloc(sizeof(*mq), GFP_KERNEL);
+ if (!mq)
+ return NULL;
+
+ mq->dev = dev;
+ mq->recvbufdcsp = kmem_cache_zalloc(maple_queue_cache, GFP_KERNEL);
+ mq->recvbuf = (void *) P2SEGADDR(mq->recvbufdcsp);
+ if (!mq->recvbuf) {
+ kfree(mq);
+ return NULL;
+ }
+
+ return mq;
+}
+
+static struct maple_device *maple_alloc_dev(int port, int unit)
+{
+ struct maple_device *dev;
+
+ dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+ if (!dev)
+ return NULL;
+
+ dev->port = port;
+ dev->unit = unit;
+ dev->mq = maple_allocq(dev);
+
+ if (!dev->mq) {
+ kfree(dev);
+ return NULL;
+ }
+
+ return dev;
+}
+
+static void maple_free_dev(struct maple_device *mdev)
+{
+ if (!mdev)
+ return;
+ if (mdev->mq) {
+ kmem_cache_free(maple_queue_cache, mdev->mq->recvbufdcsp);
+ kfree(mdev->mq);
+ }
+ kfree(mdev);
+}
+
+/* process the command queue into a maple command block
+ * terminating command has bit 32 of first long set to 0
+ */
+static void maple_build_block(struct mapleq *mq)
+{
+ int port, unit, from, to, len;
+ unsigned long *lsendbuf = mq->sendbuf;
+
+ port = mq->dev->port & 3;
+ unit = mq->dev->unit;
+ len = mq->length;
+ from = port << 6;
+ to = (port << 6) | (unit > 0 ? (1 << (unit - 1)) & 0x1f : 0x20);
+
+ *maple_lastptr &= 0x7fffffff;
+ maple_lastptr = maple_sendptr;
+
+ *maple_sendptr++ = (port << 16) | len | 0x80000000;
+ *maple_sendptr++ = PHYSADDR(mq->recvbuf);
+ *maple_sendptr++ =
+ mq->command | (to << 8) | (from << 16) | (len << 24);
+
+ while (len-- > 0)
+ *maple_sendptr++ = *lsendbuf++;
+}
+
+/* build up command queue */
+static void maple_send(void)
+{
+ int i;
+ int maple_packets;
+ struct mapleq *mq, *nmq;
+
+ if (!list_empty(&maple_sentq))
+ return;
+ if (list_empty(&maple_waitq) || !maple_dma_done())
+ return;
+ maple_packets = 0;
+ maple_sendptr = maple_lastptr = maple_sendbuf;
+ list_for_each_entry_safe(mq, nmq, &maple_waitq, list) {
+ maple_build_block(mq);
+ list_move(&mq->list, &maple_sentq);
+ if (maple_packets++ > MAPLE_MAXPACKETS)
+ break;
+ }
+ if (maple_packets > 0) {
+ for (i = 0; i < (1 << MAPLE_DMA_PAGES); i++)
+ dma_cache_sync(0, maple_sendbuf + i * PAGE_SIZE,
+ PAGE_SIZE, DMA_BIDIRECTIONAL);
+ }
+}
+
+static int attach_matching_maple_driver(struct device_driver *driver,
+ void *devptr)
+{
+ struct maple_driver *maple_drv;
+ struct maple_device *mdev;
+
+ mdev = devptr;
+ maple_drv = to_maple_driver(driver);
+ if (mdev->devinfo.function & be32_to_cpu(maple_drv->function)) {
+ if (maple_drv->connect(mdev) == 0) {
+ mdev->driver = maple_drv;
+ return 1;
+ }
+ }
+ return 0;
+}
+
+static void maple_detach_driver(struct maple_device *mdev)
+{
+ if (!mdev)
+ return;
+ if (mdev->driver) {
+ if (mdev->driver->disconnect)
+ mdev->driver->disconnect(mdev);
+ }
+ mdev->driver = NULL;
+ if (mdev->registered) {
+ maple_release_device(&mdev->dev);
+ device_unregister(&mdev->dev);
+ }
+ mdev->registered = 0;
+ maple_free_dev(mdev);
+}
+
+/* process initial MAPLE_COMMAND_DEVINFO for each device or port */
+static void maple_attach_driver(struct maple_device *dev)
+{
+ char *p;
+
+ char *recvbuf;
+ unsigned long function;
+ int matched, retval;
+
+ recvbuf = dev->mq->recvbuf;
+ memcpy(&dev->devinfo, recvbuf + 4, sizeof(dev->devinfo));
+ memcpy(dev->product_name, dev->devinfo.product_name, 30);
+ memcpy(dev->product_licence, dev->devinfo.product_licence, 60);
+ dev->product_name[30] = '\0';
+ dev->product_licence[60] = '\0';
+
+ for (p = dev->product_name + 29; dev->product_name <= p; p--)
+ if (*p == ' ')
+ *p = '\0';
+ else
+ break;
+
+ for (p = dev->product_licence + 59; dev->product_licence <= p; p--)
+ if (*p == ' ')
+ *p = '\0';
+ else
+ break;
+
+ function = be32_to_cpu(dev->devinfo.function);
+
+ if (function > 0x200) {
+ /* Do this silently - as not a real device */
+ function = 0;
+ dev->driver = &maple_dummy_driver;
+ sprintf(dev->dev.bus_id, "%d:0.port", dev->port);
+ } else {
+ printk(KERN_INFO
+ "Maple bus at (%d, %d): Connected function 0x%lX\n",
+ dev->port, dev->unit, function);
+
+ matched =
+ bus_for_each_drv(&maple_bus_type, NULL, dev,
+ attach_matching_maple_driver);
+
+ if (matched == 0) {
+ /* Driver does not exist yet */
+ printk(KERN_INFO
+ "No maple driver found for this device\n");
+ dev->driver = &maple_dummy_driver;
+ }
+
+ sprintf(dev->dev.bus_id, "%d:0%d.%lX", dev->port,
+ dev->unit, function);
+ }
+ dev->function = function;
+ dev->dev.bus = &maple_bus_type;
+ dev->dev.parent = &maple_bus;
+ dev->dev.release = &maple_release_device;
+ retval = device_register(&dev->dev);
+ if (retval) {
+ printk(KERN_INFO
+ "Maple bus: Attempt to register device (%x, %x) failed.\n",
+ dev->port, dev->unit);
+ maple_free_dev(dev);
+ }
+ dev->registered = 1;
+}
+
+/*
+ * if device has been registered for the given
+ * port and unit then return 1 - allows identification
+ * of which devices need to be attached or detached
+ */
+static int detach_maple_device(struct device *device, void *portptr)
+{
+ struct maple_device_specify *ds;
+ struct maple_device *mdev;
+
+ ds = portptr;
+ mdev = to_maple_dev(device);
+ if (mdev->port == ds->port && mdev->unit == ds->unit)
+ return 1;
+ return 0;
+}
+
+static int setup_maple_commands(struct device *device, void *ignored)
+{
+ struct maple_device *maple_dev = to_maple_dev(device);
+
+ if ((maple_dev->interval > 0)
+ && time_after(jiffies, maple_dev->when)) {
+ maple_dev->when = jiffies + maple_dev->interval;
+ maple_dev->mq->command = MAPLE_COMMAND_GETCOND;
+ maple_dev->mq->sendbuf = &maple_dev->function;
+ maple_dev->mq->length = 1;
+ maple_add_packet(maple_dev->mq);
+ liststatus++;
+ } else {
+ if (time_after(jiffies, maple_pnp_time)) {
+ maple_dev->mq->command = MAPLE_COMMAND_DEVINFO;
+ maple_dev->mq->length = 0;
+ maple_add_packet(maple_dev->mq);
+ liststatus++;
+ }
+ }
+
+ return 0;
+}
+
+/* VBLANK bottom half - implemented via workqueue */
+static void maple_vblank_handler(struct work_struct *work)
+{
+ if (!maple_dma_done())
+ return;
+ if (!list_empty(&maple_sentq))
+ return;
+ ctrl_outl(0, MAPLE_ENABLE);
+ liststatus = 0;
+ bus_for_each_dev(&maple_bus_type, NULL, NULL,
+ setup_maple_commands);
+ if (time_after(jiffies, maple_pnp_time))
+ maple_pnp_time = jiffies + MAPLE_PNP_INTERVAL;
+ if (liststatus && list_empty(&maple_sentq)) {
+ INIT_LIST_HEAD(&maple_sentq);
+ maple_send();
+ }
+ maplebus_dma_reset();
+}
+
+/* handle devices added via hotplugs - placing them on queue for DEVINFO*/
+static void maple_map_subunits(struct maple_device *mdev, int submask)
+{
+ int retval, k, devcheck;
+ struct maple_device *mdev_add;
+ struct maple_device_specify ds;
+
+ for (k = 0; k < 5; k++) {
+ ds.port = mdev->port;
+ ds.unit = k + 1;
+ retval =
+ bus_for_each_dev(&maple_bus_type, NULL, &ds,
+ detach_maple_device);
+ if (retval) {
+ submask = submask >> 1;
+ continue;
+ }
+ devcheck = submask & 0x01;
+ if (devcheck) {
+ mdev_add = maple_alloc_dev(mdev->port, k + 1);
+ if (!mdev_add)
+ return;
+ mdev_add->mq->command = MAPLE_COMMAND_DEVINFO;
+ mdev_add->mq->length = 0;
+ maple_add_packet(mdev_add->mq);
+ scanning = 1;
+ }
+ submask = submask >> 1;
+ }
+}
+
+/* mark a device as removed */
+static void maple_clean_submap(struct maple_device *mdev)
+{
+ int killbit;
+
+ killbit = (mdev->unit > 0 ? (1 << (mdev->unit - 1)) & 0x1f : 0x20);
+ killbit = ~killbit;
+ killbit &= 0xFF;
+ subdevice_map[mdev->port] = subdevice_map[mdev->port] & killbit;
+}
+
+/* handle empty port or hotplug removal */
+static void maple_response_none(struct maple_device *mdev,
+ struct mapleq *mq)
+{
+ if (mdev->unit != 0) {
+ list_del(&mq->list);
+ maple_clean_submap(mdev);
+ printk(KERN_INFO
+ "Maple bus device detaching at (%d, %d)\n",
+ mdev->port, mdev->unit);
+ maple_detach_driver(mdev);
+ return;
+ }
+ if (!started) {
+ printk(KERN_INFO "No maple devices attached to port %d\n",
+ mdev->port);
+ return;
+ }
+ maple_clean_submap(mdev);
+}
+
+/* preprocess hotplugs or scans */
+static void maple_response_devinfo(struct maple_device *mdev,
+ char *recvbuf)
+{
+ char submask;
+ if ((!started) || (scanning == 2)) {
+ maple_attach_driver(mdev);
+ return;
+ }
+ if (mdev->unit == 0) {
+ submask = recvbuf[2] & 0x1F;
+ if (submask ^ subdevice_map[mdev->port]) {
+ maple_map_subunits(mdev, submask);
+ subdevice_map[mdev->port] = submask;
+ }
+ }
+}
+
+/* maple dma end bottom half - implemented via workqueue */
+static void maple_dma_handler(struct work_struct *work)
+{
+ struct mapleq *mq, *nmq;
+ struct maple_device *dev;
+ char *recvbuf;
+ enum maple_code code;
+
+ if (!maple_dma_done())
+ return;
+ ctrl_outl(0, MAPLE_ENABLE);
+ if (!list_empty(&maple_sentq)) {
+ list_for_each_entry_safe(mq, nmq, &maple_sentq, list) {
+ recvbuf = mq->recvbuf;
+ code = recvbuf[0];
+ dev = mq->dev;
+ switch (code) {
+ case MAPLE_RESPONSE_NONE:
+ maple_response_none(dev, mq);
+ break;
+
+ case MAPLE_RESPONSE_DEVINFO:
+ maple_response_devinfo(dev, recvbuf);
+ break;
+
+ case MAPLE_RESPONSE_DATATRF:
+ if (dev->callback)
+ dev->callback(mq);
+ break;
+
+ case MAPLE_RESPONSE_FILEERR:
+ case MAPLE_RESPONSE_AGAIN:
+ case MAPLE_RESPONSE_BADCMD:
+ case MAPLE_RESPONSE_BADFUNC:
+ printk(KERN_DEBUG
+ "Maple non-fatal error 0x%X\n",
+ code);
+ break;
+
+ case MAPLE_RESPONSE_ALLINFO:
+ printk(KERN_DEBUG
+ "Maple - extended device information not supported\n");
+ break;
+
+ case MAPLE_RESPONSE_OK:
+ break;
+
+ default:
+ break;
+ }
+ }
+ INIT_LIST_HEAD(&maple_sentq);
+ if (scanning == 1) {
+ maple_send();
+ scanning = 2;
+ } else
+ scanning = 0;
+
+ if (started == 0)
+ started = 1;
+ }
+ maplebus_dma_reset();
+}
+
+static irqreturn_t maplebus_dma_interrupt(int irq, void *dev_id)
+{
+ /* Load everything into the bottom half */
+ schedule_work(&maple_dma_process);
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t maplebus_vblank_interrupt(int irq, void *dev_id)
+{
+ schedule_work(&maple_vblank_process);
+ return IRQ_HANDLED;
+}
+
+static struct irqaction maple_dma_irq = {
+ .name = "maple bus DMA handler",
+ .handler = maplebus_dma_interrupt,
+ .flags = IRQF_SHARED,
+};
+
+static struct irqaction maple_vblank_irq = {
+ .name = "maple bus VBLANK handler",
+ .handler = maplebus_vblank_interrupt,
+ .flags = IRQF_SHARED,
+};
+
+static int maple_set_dma_interrupt_handler(void)
+{
+ return setup_irq(HW_EVENT_MAPLE_DMA, &maple_dma_irq);
+}
+
+static int maple_set_vblank_interrupt_handler(void)
+{
+ return setup_irq(HW_EVENT_VSYNC, &maple_vblank_irq);
+}
+
+static int maple_get_dma_buffer(void)
+{
+ maple_sendbuf =
+ (void *) __get_free_pages(GFP_KERNEL | __GFP_ZERO,
+ MAPLE_DMA_PAGES);
+ if (!maple_sendbuf)
+ return -ENOMEM;
+ return 0;
+}
+
+static int match_maple_bus_driver(struct device *devptr,
+ struct device_driver *drvptr)
+{
+ struct maple_driver *maple_drv;
+ struct maple_device *maple_dev;
+
+ maple_drv = container_of(drvptr, struct maple_driver, drv);
+ maple_dev = container_of(devptr, struct maple_device, dev);
+ /* Trap empty port case */
+ if (maple_dev->devinfo.function == 0xFFFFFFFF)
+ return 0;
+ else if (maple_dev->devinfo.function &
+ be32_to_cpu(maple_drv->function))
+ return 1;
+ return 0;
+}
+
+static int maple_bus_uevent(struct device *dev, char **envp,
+ int num_envp, char *buffer, int buffer_size)
+{
+ return 0;
+}
+
+static void maple_bus_release(struct device *dev)
+{
+}
+
+static struct maple_driver maple_dummy_driver = {
+ .drv = {
+ .name = "maple_dummy_driver",
+ .bus = &maple_bus_type,
+ },
+};
+
+struct bus_type maple_bus_type = {
+ .name = "maple",
+ .match = match_maple_bus_driver,
+ .uevent = maple_bus_uevent,
+};
+EXPORT_SYMBOL_GPL(maple_bus_type);
+
+static struct device maple_bus = {
+ .bus_id = "maple",
+ .release = maple_bus_release,
+};
+
+static int __init maple_bus_init(void)
+{
+ int retval, i;
+ struct maple_device *mdev[MAPLE_PORTS];
+ ctrl_outl(0, MAPLE_STATE);
+
+ retval = device_register(&maple_bus);
+ if (retval)
+ goto cleanup;
+
+ retval = bus_register(&maple_bus_type);
+ if (retval)
+ goto cleanup_device;
+
+ retval = driver_register(&maple_dummy_driver.drv);
+
+ if (retval)
+ goto cleanup_bus;
+
+ /* allocate memory for maple bus dma */
+ retval = maple_get_dma_buffer();
+ if (retval) {
+ printk(KERN_INFO
+ "Maple bus: Failed to allocate Maple DMA buffers\n");
+ goto cleanup_basic;
+ }
+
+ /* set up DMA interrupt handler */
+ retval = maple_set_dma_interrupt_handler();
+ if (retval) {
+ printk(KERN_INFO
+ "Maple bus: Failed to grab maple DMA IRQ\n");
+ goto cleanup_dma;
+ }
+
+ /* set up VBLANK interrupt handler */
+ retval = maple_set_vblank_interrupt_handler();
+ if (retval) {
+ printk(KERN_INFO "Maple bus: Failed to grab VBLANK IRQ\n");
+ goto cleanup_irq;
+ }
+
+ maple_queue_cache =
+ kmem_cache_create("maple_queue_cache", 0x400, 0,
+ SLAB_HWCACHE_ALIGN, NULL);
+
+ if (!maple_queue_cache)
+ goto cleanup_bothirqs;
+
+ /* setup maple ports */
+ for (i = 0; i < MAPLE_PORTS; i++) {
+ mdev[i] = maple_alloc_dev(i, 0);
+ if (!mdev[i]) {
+ while (i-- > 0)
+ maple_free_dev(mdev[i]);
+ goto cleanup_cache;
+ }
+ mdev[i]->registered = 0;
+ mdev[i]->mq->command = MAPLE_COMMAND_DEVINFO;
+ mdev[i]->mq->length = 0;
+ maple_attach_driver(mdev[i]);
+ maple_add_packet(mdev[i]->mq);
+ subdevice_map[i] = 0;
+ }
+
+ /* setup maplebus hardware */
+ maplebus_dma_reset();
+
+ /* initial detection */
+ maple_send();
+
+ maple_pnp_time = jiffies;
+
+ printk(KERN_INFO "Maple bus core now registered.\n");
+
+ return 0;
+
+cleanup_cache:
+ kmem_cache_destroy(maple_queue_cache);
+
+cleanup_bothirqs:
+ free_irq(HW_EVENT_VSYNC, 0);
+
+cleanup_irq:
+ free_irq(HW_EVENT_MAPLE_DMA, 0);
+
+cleanup_dma:
+ free_pages((unsigned long) maple_sendbuf, MAPLE_DMA_PAGES);
+
+cleanup_basic:
+ driver_unregister(&maple_dummy_driver.drv);
+
+cleanup_bus:
+ bus_unregister(&maple_bus_type);
+
+cleanup_device:
+ device_unregister(&maple_bus);
+
+cleanup:
+ printk(KERN_INFO "Maple bus registration failed\n");
+ return retval;
+}
+subsys_initcall(maple_bus_init);