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-rw-r--r--kernel/drivers/sh/maple/Makefile3
-rw-r--r--kernel/drivers/sh/maple/maple.c893
2 files changed, 896 insertions, 0 deletions
diff --git a/kernel/drivers/sh/maple/Makefile b/kernel/drivers/sh/maple/Makefile
new file mode 100644
index 000000000..65dfeeb61
--- /dev/null
+++ b/kernel/drivers/sh/maple/Makefile
@@ -0,0 +1,3 @@
+# Makefile for Maple Bus
+
+obj-$(CONFIG_MAPLE) := maple.o
diff --git a/kernel/drivers/sh/maple/maple.c b/kernel/drivers/sh/maple/maple.c
new file mode 100644
index 000000000..bec81c240
--- /dev/null
+++ b/kernel/drivers/sh/maple/maple.c
@@ -0,0 +1,893 @@
+/*
+ * Core maple bus functionality
+ *
+ * Copyright (C) 2007 - 2009 Adrian McMenamin
+ * Copyright (C) 2001 - 2008 Paul Mundt
+ * Copyright (C) 2000 - 2001 YAEGASHI Takeshi
+ * Copyright (C) 2001 M. R. Brown
+ *
+ * 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/interrupt.h>
+#include <linux/list.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/maple.h>
+#include <linux/dma-mapping.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <asm/cacheflush.h>
+#include <asm/dma.h>
+#include <asm/io.h>
+#include <mach/dma.h>
+#include <mach/sysasic.h>
+
+MODULE_AUTHOR("Adrian McMenamin <adrian@mcmen.demon.co.uk>");
+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);
+
+/* mutex to protect queue of waiting packets */
+static DEFINE_MUTEX(maple_wlist_lock);
+
+static struct maple_driver maple_unsupported_device;
+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, fullscan;
+static struct kmem_cache *maple_queue_cache;
+
+struct maple_device_specify {
+ int port;
+ int unit;
+};
+
+static bool checked[MAPLE_PORTS];
+static bool empty[MAPLE_PORTS];
+static struct maple_device *baseunits[MAPLE_PORTS];
+
+/**
+ * maple_driver_register - register a maple driver
+ * @drv: maple driver to be registered.
+ *
+ * Registers the passed in @drv, while updating the bus type.
+ * Devices with matching function IDs will be automatically probed.
+ */
+int maple_driver_register(struct maple_driver *drv)
+{
+ if (!drv)
+ return -EINVAL;
+
+ drv->drv.bus = &maple_bus_type;
+
+ return driver_register(&drv->drv);
+}
+EXPORT_SYMBOL_GPL(maple_driver_register);
+
+/**
+ * maple_driver_unregister - unregister a maple driver.
+ * @drv: maple driver to unregister.
+ *
+ * Cleans up after maple_driver_register(). To be invoked in the exit
+ * path of any module drivers.
+ */
+void maple_driver_unregister(struct maple_driver *drv)
+{
+ driver_unregister(&drv->drv);
+}
+EXPORT_SYMBOL_GPL(maple_driver_unregister);
+
+/* set hardware registers to enable next round of dma */
+static void maple_dma_reset(void)
+{
+ __raw_writel(MAPLE_MAGIC, MAPLE_RESET);
+ /* set trig type to 0 for software trigger, 1 for hardware (VBLANK) */
+ __raw_writel(1, MAPLE_TRIGTYPE);
+ /*
+ * Maple system register
+ * bits 31 - 16 timeout in units of 20nsec
+ * bit 12 hard trigger - set 0 to keep responding to VBLANK
+ * bits 9 - 8 set 00 for 2 Mbps, 01 for 1 Mbps
+ * bits 3 - 0 delay (in 1.3ms) between VBLANK and start of DMA
+ * max delay is 11
+ */
+ __raw_writel(MAPLE_2MBPS | MAPLE_TIMEOUT(0xFFFF), MAPLE_SPEED);
+ __raw_writel(virt_to_phys(maple_sendbuf), MAPLE_DMAADDR);
+ __raw_writel(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 (__raw_readl(MAPLE_STATE) & 1) == 0;
+}
+
+static void maple_release_device(struct device *dev)
+{
+ struct maple_device *mdev;
+ struct mapleq *mq;
+
+ mdev = to_maple_dev(dev);
+ mq = mdev->mq;
+ kmem_cache_free(maple_queue_cache, mq->recvbuf);
+ kfree(mq);
+ kfree(mdev);
+}
+
+/**
+ * maple_add_packet - add a single instruction to the maple bus queue
+ * @mdev: maple device
+ * @function: function on device being queried
+ * @command: maple command to add
+ * @length: length of command string (in 32 bit words)
+ * @data: remainder of command string
+ */
+int maple_add_packet(struct maple_device *mdev, u32 function, u32 command,
+ size_t length, void *data)
+{
+ int ret = 0;
+ void *sendbuf = NULL;
+
+ if (length) {
+ sendbuf = kzalloc(length * 4, GFP_KERNEL);
+ if (!sendbuf) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ ((__be32 *)sendbuf)[0] = cpu_to_be32(function);
+ }
+
+ mdev->mq->command = command;
+ mdev->mq->length = length;
+ if (length > 1)
+ memcpy(sendbuf + 4, data, (length - 1) * 4);
+ mdev->mq->sendbuf = sendbuf;
+
+ mutex_lock(&maple_wlist_lock);
+ list_add_tail(&mdev->mq->list, &maple_waitq);
+ mutex_unlock(&maple_wlist_lock);
+out:
+ return ret;
+}
+EXPORT_SYMBOL_GPL(maple_add_packet);
+
+static struct mapleq *maple_allocq(struct maple_device *mdev)
+{
+ struct mapleq *mq;
+
+ mq = kzalloc(sizeof(*mq), GFP_KERNEL);
+ if (!mq)
+ goto failed_nomem;
+
+ INIT_LIST_HEAD(&mq->list);
+ mq->dev = mdev;
+ mq->recvbuf = kmem_cache_zalloc(maple_queue_cache, GFP_KERNEL);
+ if (!mq->recvbuf)
+ goto failed_p2;
+ mq->recvbuf->buf = &((mq->recvbuf->bufx)[0]);
+
+ return mq;
+
+failed_p2:
+ kfree(mq);
+failed_nomem:
+ dev_err(&mdev->dev, "could not allocate memory for device (%d, %d)\n",
+ mdev->port, mdev->unit);
+ return NULL;
+}
+
+static struct maple_device *maple_alloc_dev(int port, int unit)
+{
+ struct maple_device *mdev;
+
+ /* zero this out to avoid kobj subsystem
+ * thinking it has already been registered */
+
+ mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
+ if (!mdev)
+ return NULL;
+
+ mdev->port = port;
+ mdev->unit = unit;
+
+ mdev->mq = maple_allocq(mdev);
+
+ if (!mdev->mq) {
+ kfree(mdev);
+ return NULL;
+ }
+ mdev->dev.bus = &maple_bus_type;
+ mdev->dev.parent = &maple_bus;
+ init_waitqueue_head(&mdev->maple_wait);
+ return mdev;
+}
+
+static void maple_free_dev(struct maple_device *mdev)
+{
+ kmem_cache_free(maple_queue_cache, mdev->mq->recvbuf);
+ 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++ = virt_to_phys(mq->recvbuf->buf);
+ *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, maple_packets = 0;
+ struct mapleq *mq, *nmq;
+
+ if (!maple_dma_done())
+ return;
+
+ /* disable DMA */
+ __raw_writel(0, MAPLE_ENABLE);
+
+ if (!list_empty(&maple_sentq))
+ goto finish;
+
+ mutex_lock(&maple_wlist_lock);
+ if (list_empty(&maple_waitq)) {
+ mutex_unlock(&maple_wlist_lock);
+ goto finish;
+ }
+
+ maple_lastptr = maple_sendbuf;
+ maple_sendptr = maple_sendbuf;
+
+ list_for_each_entry_safe(mq, nmq, &maple_waitq, list) {
+ maple_build_block(mq);
+ list_del_init(&mq->list);
+ list_add_tail(&mq->list, &maple_sentq);
+ if (maple_packets++ > MAPLE_MAXPACKETS)
+ break;
+ }
+ mutex_unlock(&maple_wlist_lock);
+ 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);
+ }
+
+finish:
+ maple_dma_reset();
+}
+
+/* check if there is a driver registered likely to match this device */
+static int maple_check_matching_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 & cpu_to_be32(maple_drv->function))
+ return 1;
+ return 0;
+}
+
+static void maple_detach_driver(struct maple_device *mdev)
+{
+ device_unregister(&mdev->dev);
+}
+
+/* process initial MAPLE_COMMAND_DEVINFO for each device or port */
+static void maple_attach_driver(struct maple_device *mdev)
+{
+ char *p, *recvbuf;
+ unsigned long function;
+ int matched, error;
+
+ recvbuf = mdev->mq->recvbuf->buf;
+ /* copy the data as individual elements in
+ * case of memory optimisation */
+ memcpy(&mdev->devinfo.function, recvbuf + 4, 4);
+ memcpy(&mdev->devinfo.function_data[0], recvbuf + 8, 12);
+ memcpy(&mdev->devinfo.area_code, recvbuf + 20, 1);
+ memcpy(&mdev->devinfo.connector_direction, recvbuf + 21, 1);
+ memcpy(&mdev->devinfo.product_name[0], recvbuf + 22, 30);
+ memcpy(&mdev->devinfo.standby_power, recvbuf + 112, 2);
+ memcpy(&mdev->devinfo.max_power, recvbuf + 114, 2);
+ memcpy(mdev->product_name, mdev->devinfo.product_name, 30);
+ mdev->product_name[30] = '\0';
+ memcpy(mdev->product_licence, mdev->devinfo.product_licence, 60);
+ mdev->product_licence[60] = '\0';
+
+ for (p = mdev->product_name + 29; mdev->product_name <= p; p--)
+ if (*p == ' ')
+ *p = '\0';
+ else
+ break;
+ for (p = mdev->product_licence + 59; mdev->product_licence <= p; p--)
+ if (*p == ' ')
+ *p = '\0';
+ else
+ break;
+
+ function = be32_to_cpu(mdev->devinfo.function);
+
+ dev_info(&mdev->dev, "detected %s: function 0x%lX: at (%d, %d)\n",
+ mdev->product_name, function, mdev->port, mdev->unit);
+
+ if (function > 0x200) {
+ /* Do this silently - as not a real device */
+ function = 0;
+ mdev->driver = &maple_unsupported_device;
+ dev_set_name(&mdev->dev, "%d:0.port", mdev->port);
+ } else {
+ matched =
+ bus_for_each_drv(&maple_bus_type, NULL, mdev,
+ maple_check_matching_driver);
+
+ if (matched == 0) {
+ /* Driver does not exist yet */
+ dev_info(&mdev->dev, "no driver found\n");
+ mdev->driver = &maple_unsupported_device;
+ }
+ dev_set_name(&mdev->dev, "%d:0%d.%lX", mdev->port,
+ mdev->unit, function);
+ }
+
+ mdev->function = function;
+ mdev->dev.release = &maple_release_device;
+
+ atomic_set(&mdev->busy, 0);
+ error = device_register(&mdev->dev);
+ if (error) {
+ dev_warn(&mdev->dev, "could not register device at"
+ " (%d, %d), with error 0x%X\n", mdev->unit,
+ mdev->port, error);
+ maple_free_dev(mdev);
+ mdev = NULL;
+ return;
+ }
+}
+
+/*
+ * 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 check_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)
+{
+ int add;
+ struct maple_device *mdev = to_maple_dev(device);
+ if (mdev->interval > 0 && atomic_read(&mdev->busy) == 0 &&
+ time_after(jiffies, mdev->when)) {
+ /* bounce if we cannot add */
+ add = maple_add_packet(mdev,
+ be32_to_cpu(mdev->devinfo.function),
+ MAPLE_COMMAND_GETCOND, 1, NULL);
+ if (!add)
+ mdev->when = jiffies + mdev->interval;
+ } else {
+ if (time_after(jiffies, maple_pnp_time))
+ /* Ensure we don't have block reads and devinfo
+ * calls interfering with one another - so flag the
+ * device as busy */
+ if (atomic_read(&mdev->busy) == 0) {
+ atomic_set(&mdev->busy, 1);
+ maple_add_packet(mdev, 0,
+ MAPLE_COMMAND_DEVINFO, 0, NULL);
+ }
+ }
+ return 0;
+}
+
+/* VBLANK bottom half - implemented via workqueue */
+static void maple_vblank_handler(struct work_struct *work)
+{
+ int x, locking;
+ struct maple_device *mdev;
+
+ if (!maple_dma_done())
+ return;
+
+ __raw_writel(0, MAPLE_ENABLE);
+
+ if (!list_empty(&maple_sentq))
+ goto finish;
+
+ /*
+ * Set up essential commands - to fetch data and
+ * check devices are still present
+ */
+ bus_for_each_dev(&maple_bus_type, NULL, NULL,
+ setup_maple_commands);
+
+ if (time_after(jiffies, maple_pnp_time)) {
+ /*
+ * Scan the empty ports - bus is flakey and may have
+ * mis-reported emptyness
+ */
+ for (x = 0; x < MAPLE_PORTS; x++) {
+ if (checked[x] && empty[x]) {
+ mdev = baseunits[x];
+ if (!mdev)
+ break;
+ atomic_set(&mdev->busy, 1);
+ locking = maple_add_packet(mdev, 0,
+ MAPLE_COMMAND_DEVINFO, 0, NULL);
+ if (!locking)
+ break;
+ }
+ }
+
+ maple_pnp_time = jiffies + MAPLE_PNP_INTERVAL;
+ }
+
+finish:
+ maple_send();
+}
+
+/* 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;
+
+ ds.port = mdev->port;
+ for (k = 0; k < 5; k++) {
+ ds.unit = k + 1;
+ retval =
+ bus_for_each_dev(&maple_bus_type, NULL, &ds,
+ check_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;
+ atomic_set(&mdev_add->busy, 1);
+ maple_add_packet(mdev_add, 0, MAPLE_COMMAND_DEVINFO,
+ 0, NULL);
+ /* mark that we are checking sub devices */
+ 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)
+{
+ maple_clean_submap(mdev);
+
+ if (likely(mdev->unit != 0)) {
+ /*
+ * Block devices play up
+ * and give the impression they have
+ * been removed even when still in place or
+ * trip the mtd layer when they have
+ * really gone - this code traps that eventuality
+ * and ensures we aren't overloaded with useless
+ * error messages
+ */
+ if (mdev->can_unload) {
+ if (!mdev->can_unload(mdev)) {
+ atomic_set(&mdev->busy, 2);
+ wake_up(&mdev->maple_wait);
+ return;
+ }
+ }
+
+ dev_info(&mdev->dev, "detaching device at (%d, %d)\n",
+ mdev->port, mdev->unit);
+ maple_detach_driver(mdev);
+ return;
+ } else {
+ if (!started || !fullscan) {
+ if (checked[mdev->port] == false) {
+ checked[mdev->port] = true;
+ empty[mdev->port] = true;
+ dev_info(&mdev->dev, "no devices"
+ " to port %d\n", mdev->port);
+ }
+ return;
+ }
+ }
+ /* Some hardware devices generate false detach messages on unit 0 */
+ atomic_set(&mdev->busy, 0);
+}
+
+/* preprocess hotplugs or scans */
+static void maple_response_devinfo(struct maple_device *mdev,
+ char *recvbuf)
+{
+ char submask;
+ if (!started || (scanning == 2) || !fullscan) {
+ if ((mdev->unit == 0) && (checked[mdev->port] == false)) {
+ checked[mdev->port] = true;
+ maple_attach_driver(mdev);
+ } else {
+ if (mdev->unit != 0)
+ maple_attach_driver(mdev);
+ if (mdev->unit == 0) {
+ empty[mdev->port] = false;
+ maple_attach_driver(mdev);
+ }
+ }
+ }
+ if (mdev->unit == 0) {
+ submask = recvbuf[2] & 0x1F;
+ if (submask ^ subdevice_map[mdev->port]) {
+ maple_map_subunits(mdev, submask);
+ subdevice_map[mdev->port] = submask;
+ }
+ }
+}
+
+static void maple_response_fileerr(struct maple_device *mdev, void *recvbuf)
+{
+ if (mdev->fileerr_handler) {
+ mdev->fileerr_handler(mdev, recvbuf);
+ return;
+ } else
+ dev_warn(&mdev->dev, "device at (%d, %d) reports"
+ "file error 0x%X\n", mdev->port, mdev->unit,
+ ((int *)recvbuf)[1]);
+}
+
+static void maple_port_rescan(void)
+{
+ int i;
+ struct maple_device *mdev;
+
+ fullscan = 1;
+ for (i = 0; i < MAPLE_PORTS; i++) {
+ if (checked[i] == false) {
+ fullscan = 0;
+ mdev = baseunits[i];
+ maple_add_packet(mdev, 0, MAPLE_COMMAND_DEVINFO,
+ 0, NULL);
+ }
+ }
+}
+
+/* maple dma end bottom half - implemented via workqueue */
+static void maple_dma_handler(struct work_struct *work)
+{
+ struct mapleq *mq, *nmq;
+ struct maple_device *mdev;
+ char *recvbuf;
+ enum maple_code code;
+
+ if (!maple_dma_done())
+ return;
+ __raw_writel(0, MAPLE_ENABLE);
+ if (!list_empty(&maple_sentq)) {
+ list_for_each_entry_safe(mq, nmq, &maple_sentq, list) {
+ mdev = mq->dev;
+ recvbuf = mq->recvbuf->buf;
+ dma_cache_sync(&mdev->dev, recvbuf, 0x400,
+ DMA_FROM_DEVICE);
+ code = recvbuf[0];
+ kfree(mq->sendbuf);
+ list_del_init(&mq->list);
+ switch (code) {
+ case MAPLE_RESPONSE_NONE:
+ maple_response_none(mdev);
+ break;
+
+ case MAPLE_RESPONSE_DEVINFO:
+ maple_response_devinfo(mdev, recvbuf);
+ atomic_set(&mdev->busy, 0);
+ break;
+
+ case MAPLE_RESPONSE_DATATRF:
+ if (mdev->callback)
+ mdev->callback(mq);
+ atomic_set(&mdev->busy, 0);
+ wake_up(&mdev->maple_wait);
+ break;
+
+ case MAPLE_RESPONSE_FILEERR:
+ maple_response_fileerr(mdev, recvbuf);
+ atomic_set(&mdev->busy, 0);
+ wake_up(&mdev->maple_wait);
+ break;
+
+ case MAPLE_RESPONSE_AGAIN:
+ case MAPLE_RESPONSE_BADCMD:
+ case MAPLE_RESPONSE_BADFUNC:
+ dev_warn(&mdev->dev, "non-fatal error"
+ " 0x%X at (%d, %d)\n", code,
+ mdev->port, mdev->unit);
+ atomic_set(&mdev->busy, 0);
+ break;
+
+ case MAPLE_RESPONSE_ALLINFO:
+ dev_notice(&mdev->dev, "extended"
+ " device information request for (%d, %d)"
+ " but call is not supported\n", mdev->port,
+ mdev->unit);
+ atomic_set(&mdev->busy, 0);
+ break;
+
+ case MAPLE_RESPONSE_OK:
+ atomic_set(&mdev->busy, 0);
+ wake_up(&mdev->maple_wait);
+ break;
+
+ default:
+ break;
+ }
+ }
+ /* if scanning is 1 then we have subdevices to check */
+ if (scanning == 1) {
+ maple_send();
+ scanning = 2;
+ } else
+ scanning = 0;
+ /*check if we have actually tested all ports yet */
+ if (!fullscan)
+ maple_port_rescan();
+ /* mark that we have been through the first scan */
+ started = 1;
+ }
+ maple_send();
+}
+
+static irqreturn_t maple_dma_interrupt(int irq, void *dev_id)
+{
+ /* Load everything into the bottom half */
+ schedule_work(&maple_dma_process);
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t maple_vblank_interrupt(int irq, void *dev_id)
+{
+ schedule_work(&maple_vblank_process);
+ return IRQ_HANDLED;
+}
+
+static int maple_set_dma_interrupt_handler(void)
+{
+ return request_irq(HW_EVENT_MAPLE_DMA, maple_dma_interrupt,
+ IRQF_SHARED, "maple bus DMA", &maple_unsupported_device);
+}
+
+static int maple_set_vblank_interrupt_handler(void)
+{
+ return request_irq(HW_EVENT_VSYNC, maple_vblank_interrupt,
+ IRQF_SHARED, "maple bus VBLANK", &maple_unsupported_device);
+}
+
+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 maple_match_bus_driver(struct device *devptr,
+ struct device_driver *drvptr)
+{
+ struct maple_driver *maple_drv = to_maple_driver(drvptr);
+ struct maple_device *maple_dev = to_maple_dev(devptr);
+
+ /* Trap empty port case */
+ if (maple_dev->devinfo.function == 0xFFFFFFFF)
+ return 0;
+ else if (maple_dev->devinfo.function &
+ cpu_to_be32(maple_drv->function))
+ return 1;
+ return 0;
+}
+
+static int maple_bus_uevent(struct device *dev,
+ struct kobj_uevent_env *env)
+{
+ return 0;
+}
+
+static void maple_bus_release(struct device *dev)
+{
+}
+
+static struct maple_driver maple_unsupported_device = {
+ .drv = {
+ .name = "maple_unsupported_device",
+ .bus = &maple_bus_type,
+ },
+};
+/*
+ * maple_bus_type - core maple bus structure
+ */
+struct bus_type maple_bus_type = {
+ .name = "maple",
+ .match = maple_match_bus_driver,
+ .uevent = maple_bus_uevent,
+};
+EXPORT_SYMBOL_GPL(maple_bus_type);
+
+static struct device maple_bus = {
+ .init_name = "maple",
+ .release = maple_bus_release,
+};
+
+static int __init maple_bus_init(void)
+{
+ int retval, i;
+ struct maple_device *mdev[MAPLE_PORTS];
+
+ __raw_writel(0, MAPLE_ENABLE);
+
+ retval = device_register(&maple_bus);
+ if (retval)
+ goto cleanup;
+
+ retval = bus_register(&maple_bus_type);
+ if (retval)
+ goto cleanup_device;
+
+ retval = driver_register(&maple_unsupported_device.drv);
+ if (retval)
+ goto cleanup_bus;
+
+ /* allocate memory for maple bus dma */
+ retval = maple_get_dma_buffer();
+ if (retval) {
+ dev_err(&maple_bus, "failed to allocate DMA buffers\n");
+ goto cleanup_basic;
+ }
+
+ /* set up DMA interrupt handler */
+ retval = maple_set_dma_interrupt_handler();
+ if (retval) {
+ dev_err(&maple_bus, "bus failed to grab maple "
+ "DMA IRQ\n");
+ goto cleanup_dma;
+ }
+
+ /* set up VBLANK interrupt handler */
+ retval = maple_set_vblank_interrupt_handler();
+ if (retval) {
+ dev_err(&maple_bus, "bus failed to grab VBLANK IRQ\n");
+ goto cleanup_irq;
+ }
+
+ maple_queue_cache = KMEM_CACHE(maple_buffer, SLAB_HWCACHE_ALIGN);
+
+ if (!maple_queue_cache)
+ goto cleanup_bothirqs;
+
+ INIT_LIST_HEAD(&maple_waitq);
+ INIT_LIST_HEAD(&maple_sentq);
+
+ /* setup maple ports */
+ for (i = 0; i < MAPLE_PORTS; i++) {
+ checked[i] = false;
+ empty[i] = false;
+ mdev[i] = maple_alloc_dev(i, 0);
+ if (!mdev[i]) {
+ while (i-- > 0)
+ maple_free_dev(mdev[i]);
+ goto cleanup_cache;
+ }
+ baseunits[i] = mdev[i];
+ atomic_set(&mdev[i]->busy, 1);
+ maple_add_packet(mdev[i], 0, MAPLE_COMMAND_DEVINFO, 0, NULL);
+ subdevice_map[i] = 0;
+ }
+
+ maple_pnp_time = jiffies + HZ;
+ /* prepare initial queue */
+ maple_send();
+ dev_info(&maple_bus, "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_unsupported_device.drv);
+
+cleanup_bus:
+ bus_unregister(&maple_bus_type);
+
+cleanup_device:
+ device_unregister(&maple_bus);
+
+cleanup:
+ printk(KERN_ERR "Maple bus registration failed\n");
+ return retval;
+}
+/* Push init to later to ensure hardware gets detected */
+fs_initcall(maple_bus_init);