Merge branch 'linus' into core/futexes

1 files changed, 238 insertions, 233 deletions

diff --git a/drivers/sh/maple/maple.c b/drivers/sh/maple/maple.c
index 63f0de29aa14..cab1ab7cfb78 100644
--- a/drivers/sh/maple/maple.c
+++ b/drivers/sh/maple/maple.c
@@ -1,16 +1,10 @@
 /*
  * Core maple bus functionality
  *
- *  Copyright (C) 2007, 2008 Adrian McMenamin
+ *  Copyright (C) 2007 - 2009 Adrian McMenamin
  *  Copyright (C) 2001 - 2008 Paul Mundt
- *
- * Based on 2.4 code by:
- *
- *  Copyright (C) 2000-2001 YAEGASHI Takeshi
+ *  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
@@ -32,7 +26,7 @@
 #include <mach/dma.h>
 #include <mach/sysasic.h>
 
-MODULE_AUTHOR("Yaegashi Takeshi, Paul Mundt, M. R. Brown, Adrian McMenamin");
+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}}");
@@ -49,7 +43,7 @@ static LIST_HEAD(maple_sentq);
 /* mutex to protect queue of waiting packets */
 static DEFINE_MUTEX(maple_wlist_lock);
 
-static struct maple_driver maple_dummy_driver;
+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;
@@ -62,8 +56,9 @@ struct maple_device_specify {
         int unit;
 };
 
-static bool checked[4];
-static struct maple_device *baseunits[4];
+static bool checked[MAPLE_PORTS];
+static bool empty[MAPLE_PORTS];
+static struct maple_device *baseunits[MAPLE_PORTS];
 
 /**
  * maple_driver_register - register a maple driver
@@ -97,12 +92,20 @@ void maple_driver_unregister(struct maple_driver *drv)
 EXPORT_SYMBOL_GPL(maple_driver_unregister);
 
 /* set hardware registers to enable next round of dma */
-static void maplebus_dma_reset(void)
+static void maple_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);
+        /*
+        * 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
+        */
+        ctrl_outl(MAPLE_2MBPS | MAPLE_TIMEOUT(0xFFFF), MAPLE_SPEED);
         ctrl_outl(PHYSADDR(maple_sendbuf), MAPLE_DMAADDR);
         ctrl_outl(1, MAPLE_ENABLE);
 }
@@ -134,21 +137,16 @@ static void maple_release_device(struct device *dev)
 {
         struct maple_device *mdev;
         struct mapleq *mq;
-        if (!dev)
-                return;
+
         mdev = to_maple_dev(dev);
         mq = mdev->mq;
-        if (mq) {
-                if (mq->recvbufdcsp)
-                        kmem_cache_free(maple_queue_cache, mq->recvbufdcsp);
-                kfree(mq);
-                mq = NULL;
-        }
+        kmem_cache_free(maple_queue_cache, mq->recvbuf);
+        kfree(mq);
         kfree(mdev);
 }
 
 /**
- * maple_add_packet - add a single instruction to the queue
+ * 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
@@ -158,68 +156,12 @@ static void maple_release_device(struct device *dev)
 int maple_add_packet(struct maple_device *mdev, u32 function, u32 command,
         size_t length, void *data)
 {
-        int locking, ret = 0;
+        int ret = 0;
         void *sendbuf = NULL;
 
-        mutex_lock(&maple_wlist_lock);
-        /* bounce if device already locked */
-        locking = mutex_is_locked(&mdev->mq->mutex);
-        if (locking) {
-                ret = -EBUSY;
-                goto out;
-        }
-
-        mutex_lock(&mdev->mq->mutex);
-
         if (length) {
-                sendbuf = kmalloc(length * 4, GFP_KERNEL);
+                sendbuf = kzalloc(length * 4, GFP_KERNEL);
                 if (!sendbuf) {
-                        mutex_unlock(&mdev->mq->mutex);
-                        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;
-
-        list_add(&mdev->mq->list, &maple_waitq);
-out:
-        mutex_unlock(&maple_wlist_lock);
-        return ret;
-}
-EXPORT_SYMBOL_GPL(maple_add_packet);
-
-/**
- * maple_add_packet_sleeps - add a single instruction to the 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
- *
- * Same as maple_add_packet(), but waits for the lock to become free.
- */
-int maple_add_packet_sleeps(struct maple_device *mdev, u32 function,
-        u32 command, size_t length, void *data)
-{
-        int locking, ret = 0;
-        void *sendbuf = NULL;
-
-        locking = mutex_lock_interruptible(&mdev->mq->mutex);
-        if (locking) {
-                ret = -EIO;
-                goto out;
-        }
-
-        if (length) {
-                sendbuf = kmalloc(length * 4, GFP_KERNEL);
-                if (!sendbuf) {
-                        mutex_unlock(&mdev->mq->mutex);
                         ret = -ENOMEM;
                         goto out;
                 }
@@ -233,38 +175,35 @@ int maple_add_packet_sleeps(struct maple_device *mdev, u32 function,
         mdev->mq->sendbuf = sendbuf;
 
         mutex_lock(&maple_wlist_lock);
-        list_add(&mdev->mq->list, &maple_waitq);
+        list_add_tail(&mdev->mq->list, &maple_waitq);
         mutex_unlock(&maple_wlist_lock);
 out:
         return ret;
 }
-EXPORT_SYMBOL_GPL(maple_add_packet_sleeps);
+EXPORT_SYMBOL_GPL(maple_add_packet);
 
 static struct mapleq *maple_allocq(struct maple_device *mdev)
 {
         struct mapleq *mq;
 
-        mq = kmalloc(sizeof(*mq), GFP_KERNEL);
+        mq = kzalloc(sizeof(*mq), GFP_KERNEL);
         if (!mq)
                 goto failed_nomem;
 
+        INIT_LIST_HEAD(&mq->list);
         mq->dev = mdev;
-        mq->recvbufdcsp = kmem_cache_zalloc(maple_queue_cache, GFP_KERNEL);
-        mq->recvbuf = (void *) P2SEGADDR(mq->recvbufdcsp);
+        mq->recvbuf = kmem_cache_zalloc(maple_queue_cache, GFP_KERNEL);
         if (!mq->recvbuf)
                 goto failed_p2;
-        /*
-         * most devices do not need the mutex - but
-         * anything that injects block reads or writes
-         * will rely on it
-         */
-        mutex_init(&mq->mutex);
+        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;
 }
 
@@ -272,12 +211,16 @@ 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) {
@@ -286,19 +229,14 @@ static struct maple_device *maple_alloc_dev(int port, int unit)
         }
         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)
 {
-        if (!mdev)
-                return;
-        if (mdev->mq) {
-                if (mdev->mq->recvbufdcsp)
-                        kmem_cache_free(maple_queue_cache,
-                                mdev->mq->recvbufdcsp);
-                kfree(mdev->mq);
-        }
+        kmem_cache_free(maple_queue_cache, mdev->mq->recvbuf);
+        kfree(mdev->mq);
         kfree(mdev);
 }
 
@@ -320,7 +258,7 @@ static void maple_build_block(struct mapleq *mq)
         maple_lastptr = maple_sendptr;
 
         *maple_sendptr++ = (port << 16) | len | 0x80000000;
-        *maple_sendptr++ = PHYSADDR(mq->recvbuf);
+        *maple_sendptr++ = PHYSADDR(mq->recvbuf->buf);
         *maple_sendptr++ =
             mq->command | (to << 8) | (from << 16) | (len << 24);
         while (len-- > 0)
@@ -333,20 +271,28 @@ static void maple_send(void)
         int i, maple_packets = 0;
         struct mapleq *mq, *nmq;
 
-        if (!list_empty(&maple_sentq))
+        if (!maple_dma_done())
                 return;
+
+        /* disable DMA */
+        ctrl_outl(0, MAPLE_ENABLE);
+
+        if (!list_empty(&maple_sentq))
+                goto finish;
+
         mutex_lock(&maple_wlist_lock);
-        if (list_empty(&maple_waitq) || !maple_dma_done()) {
+        if (list_empty(&maple_waitq)) {
                 mutex_unlock(&maple_wlist_lock);
-                return;
+                goto finish;
         }
-        mutex_unlock(&maple_wlist_lock);
+
         maple_lastptr = maple_sendbuf;
         maple_sendptr = maple_sendbuf;
-        mutex_lock(&maple_wlist_lock);
+
         list_for_each_entry_safe(mq, nmq, &maple_waitq, list) {
                 maple_build_block(mq);
-                list_move(&mq->list, &maple_sentq);
+                list_del_init(&mq->list);
+                list_add_tail(&mq->list, &maple_sentq);
                 if (maple_packets++ > MAPLE_MAXPACKETS)
                         break;
         }
@@ -356,10 +302,13 @@ static void maple_send(void)
                         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 check_matching_maple_driver(struct device_driver *driver,
+static int maple_check_matching_driver(struct device_driver *driver,
                                         void *devptr)
 {
         struct maple_driver *maple_drv;
@@ -374,10 +323,7 @@ static int check_matching_maple_driver(struct device_driver *driver,
 
 static void maple_detach_driver(struct maple_device *mdev)
 {
-        if (!mdev)
-                return;
         device_unregister(&mdev->dev);
-        mdev = NULL;
 }
 
 /* process initial MAPLE_COMMAND_DEVINFO for each device or port */
@@ -385,9 +331,9 @@ static void maple_attach_driver(struct maple_device *mdev)
 {
         char *p, *recvbuf;
         unsigned long function;
-        int matched, retval;
+        int matched, error;
 
-        recvbuf = mdev->mq->recvbuf;
+        recvbuf = mdev->mq->recvbuf->buf;
         /* copy the data as individual elements in
         * case of memory optimisation */
         memcpy(&mdev->devinfo.function, recvbuf + 4, 4);
@@ -395,7 +341,6 @@ static void maple_attach_driver(struct maple_device *mdev)
         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.product_licence[0], recvbuf + 52, 60);
         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);
@@ -414,43 +359,39 @@ static void maple_attach_driver(struct maple_device *mdev)
                 else
                         break;
 
-        printk(KERN_INFO "Maple device detected: %s\n",
-                mdev->product_name);
-        printk(KERN_INFO "Maple device: %s\n", mdev->product_licence);
-
         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_dummy_driver;
-                sprintf(mdev->dev.bus_id, "%d:0.port", mdev->port);
+                mdev->driver = &maple_unsupported_device;
+                dev_set_name(&mdev->dev, "%d:0.port", mdev->port);
         } else {
-                printk(KERN_INFO
-                        "Maple bus at (%d, %d): Function 0x%lX\n",
-                        mdev->port, mdev->unit, function);
-
                 matched =
                         bus_for_each_drv(&maple_bus_type, NULL, mdev,
-                                check_matching_maple_driver);
+                                maple_check_matching_driver);
 
                 if (matched == 0) {
                         /* Driver does not exist yet */
-                        printk(KERN_INFO
-                                "No maple driver found.\n");
-                        mdev->driver = &maple_dummy_driver;
+                        dev_info(&mdev->dev, "no driver found\n");
+                        mdev->driver = &maple_unsupported_device;
                 }
-                sprintf(mdev->dev.bus_id, "%d:0%d.%lX", mdev->port,
-                        mdev->unit, function);
+                dev_set_name(&mdev->dev, "%d:0%d.%lX", mdev->port,
+                             mdev->unit, function);
         }
+
         mdev->function = function;
         mdev->dev.release = &maple_release_device;
-        retval = device_register(&mdev->dev);
-        if (retval) {
-                printk(KERN_INFO
-                "Maple bus: Attempt to register device"
-                " (%x, %x) failed.\n",
-                mdev->port, mdev->unit);
+
+        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;
@@ -462,7 +403,7 @@ static void maple_attach_driver(struct maple_device *mdev)
  * 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)
+static int check_maple_device(struct device *device, void *portptr)
 {
         struct maple_device_specify *ds;
         struct maple_device *mdev;
@@ -477,21 +418,25 @@ static int detach_maple_device(struct device *device, void *portptr)
 static int setup_maple_commands(struct device *device, void *ignored)
 {
         int add;
-        struct maple_device *maple_dev = to_maple_dev(device);
-
-        if ((maple_dev->interval > 0)
-            && time_after(jiffies, maple_dev->when)) {
-                /* bounce if we cannot lock */
-                add = maple_add_packet(maple_dev,
-                        be32_to_cpu(maple_dev->devinfo.function),
+        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)
-                        maple_dev->when = jiffies + maple_dev->interval;
+                        mdev->when = jiffies + mdev->interval;
         } else {
                 if (time_after(jiffies, maple_pnp_time))
-                        /* This will also bounce */
-                        maple_add_packet(maple_dev, 0,
-                                MAPLE_COMMAND_DEVINFO, 0, NULL);
+                        /* 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;
 }
@@ -499,29 +444,50 @@ static int setup_maple_commands(struct device *device, void *ignored)
 /* VBLANK bottom half - implemented via workqueue */
 static void maple_vblank_handler(struct work_struct *work)
 {
-        if (!list_empty(&maple_sentq) || !maple_dma_done())
+        int x, locking;
+        struct maple_device *mdev;
+
+        if (!maple_dma_done())
                 return;
 
         ctrl_outl(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);
+                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;
+                                }
+                        }
 
-        if (time_after(jiffies, maple_pnp_time))
                 maple_pnp_time = jiffies + MAPLE_PNP_INTERVAL;
-
-        mutex_lock(&maple_wlist_lock);
-        if (!list_empty(&maple_waitq) && list_empty(&maple_sentq)) {
-                mutex_unlock(&maple_wlist_lock);
-                maple_send();
-        } else {
-                mutex_unlock(&maple_wlist_lock);
         }
 
-        maplebus_dma_reset();
+finish:
+        maple_send();
 }
 
-/* handle devices added via hotplugs - placing them on queue for DEVINFO*/
+/* 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;
@@ -533,7 +499,7 @@ static void maple_map_subunits(struct maple_device *mdev, int submask)
                 ds.unit = k + 1;
                 retval =
                     bus_for_each_dev(&maple_bus_type, NULL, &ds,
-                                     detach_maple_device);
+                                     check_maple_device);
                 if (retval) {
                         submask = submask >> 1;
                         continue;
@@ -543,6 +509,7 @@ static void maple_map_subunits(struct maple_device *mdev, int submask)
                         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 */
@@ -564,27 +531,45 @@ static void maple_clean_submap(struct maple_device *mdev)
 }
 
 /* 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);
+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;
-        }
-        if (!started || !fullscan) {
-                if (checked[mdev->port] == false) {
-                        checked[mdev->port] = true;
-                        printk(KERN_INFO "No maple devices attached"
-                                " to port %d\n", mdev->port);
+        } 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;
                 }
-                return;
         }
-        maple_clean_submap(mdev);
+        /* Some hardware devices generate false detach messages on unit 0 */
+        atomic_set(&mdev->busy, 0);
 }
 
 /* preprocess hotplugs or scans */
@@ -599,8 +584,11 @@ static void maple_response_devinfo(struct maple_device *mdev,
                 } else {
                         if (mdev->unit != 0)
                                 maple_attach_driver(mdev);
+                        if (mdev->unit == 0) {
+                                empty[mdev->port] = false;
+                                maple_attach_driver(mdev);
+                        }
                 }
-                return;
         }
         if (mdev->unit == 0) {
                 submask = recvbuf[2] & 0x1F;
@@ -611,6 +599,17 @@ static void maple_response_devinfo(struct maple_device *mdev,
         }
 }
 
+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;
@@ -621,12 +620,6 @@ static void maple_port_rescan(void)
                 if (checked[i] == false) {
                         fullscan = 0;
                         mdev = baseunits[i];
-                        /*
-                         *  test lock in case scan has failed
-                         *  but device is still locked
-                         */
-                        if (mutex_is_locked(&mdev->mq->mutex))
-                                mutex_unlock(&mdev->mq->mutex);
                         maple_add_packet(mdev, 0, MAPLE_COMMAND_DEVINFO,
                                 0, NULL);
                 }
@@ -637,7 +630,7 @@ static void maple_port_rescan(void)
 static void maple_dma_handler(struct work_struct *work)
 {
         struct mapleq *mq, *nmq;
-        struct maple_device *dev;
+        struct maple_device *mdev;
         char *recvbuf;
         enum maple_code code;
 
@@ -646,43 +639,56 @@ static void maple_dma_handler(struct work_struct *work)
         ctrl_outl(0, MAPLE_ENABLE);
         if (!list_empty(&maple_sentq)) {
                 list_for_each_entry_safe(mq, nmq, &maple_sentq, list) {
-                        recvbuf = mq->recvbuf;
+                        mdev = mq->dev;
+                        recvbuf = mq->recvbuf->buf;
+                        dma_cache_sync(&mdev->dev, recvbuf, 0x400,
+                                DMA_FROM_DEVICE);
                         code = recvbuf[0];
-                        dev = mq->dev;
                         kfree(mq->sendbuf);
-                        mutex_unlock(&mq->mutex);
                         list_del_init(&mq->list);
-
                         switch (code) {
                         case MAPLE_RESPONSE_NONE:
-                                maple_response_none(dev, mq);
+                                maple_response_none(mdev);
                                 break;
 
                         case MAPLE_RESPONSE_DEVINFO:
-                                maple_response_devinfo(dev, recvbuf);
+                                maple_response_devinfo(mdev, recvbuf);
+                                atomic_set(&mdev->busy, 0);
                                 break;
 
                         case MAPLE_RESPONSE_DATATRF:
-                                if (dev->callback)
-                                        dev->callback(mq);
+                                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:
-                                printk(KERN_DEBUG
-                                       "Maple non-fatal error 0x%X\n",
-                                       code);
+                                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:
-                                printk(KERN_DEBUG
-                                       "Maple - extended device information"
-                                        " not supported\n");
+                                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:
@@ -699,20 +705,19 @@ static void maple_dma_handler(struct work_struct *work)
                 if (!fullscan)
                         maple_port_rescan();
                 /* mark that we have been through the first scan */
-                if (started == 0)
-                        started = 1;
+                started = 1;
         }
-        maplebus_dma_reset();
+        maple_send();
 }
 
-static irqreturn_t maplebus_dma_interrupt(int irq, void *dev_id)
+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 maplebus_vblank_interrupt(int irq, void *dev_id)
+static irqreturn_t maple_vblank_interrupt(int irq, void *dev_id)
 {
         schedule_work(&maple_vblank_process);
         return IRQ_HANDLED;
@@ -720,14 +725,14 @@ static irqreturn_t maplebus_vblank_interrupt(int irq, void *dev_id)
 
 static int maple_set_dma_interrupt_handler(void)
 {
-        return request_irq(HW_EVENT_MAPLE_DMA, maplebus_dma_interrupt,
-                IRQF_SHARED, "maple bus DMA", &maple_dummy_driver);
+        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, maplebus_vblank_interrupt,
-                IRQF_SHARED, "maple bus VBLANK", &maple_dummy_driver);
+        return request_irq(HW_EVENT_VSYNC, maple_vblank_interrupt,
+                IRQF_SHARED, "maple bus VBLANK", &maple_unsupported_device);
 }
 
 static int maple_get_dma_buffer(void)
@@ -740,7 +745,7 @@ static int maple_get_dma_buffer(void)
         return 0;
 }
 
-static int match_maple_bus_driver(struct device *devptr,
+static int maple_match_bus_driver(struct device *devptr,
                                   struct device_driver *drvptr)
 {
         struct maple_driver *maple_drv = to_maple_driver(drvptr);
@@ -765,22 +770,24 @@ static void maple_bus_release(struct device *dev)
 {
 }
 
-static struct maple_driver maple_dummy_driver = {
+static struct maple_driver maple_unsupported_device = {
         .drv = {
-                .name = "maple_dummy_driver",
+                .name = "maple_unsupported_device",
                 .bus = &maple_bus_type,
         },
 };
-
+/**
+ * maple_bus_type - core maple bus structure
+ */
 struct bus_type maple_bus_type = {
         .name = "maple",
-        .match = match_maple_bus_driver,
+        .match = maple_match_bus_driver,
         .uevent = maple_bus_uevent,
 };
 EXPORT_SYMBOL_GPL(maple_bus_type);
 
 static struct device maple_bus = {
-        .bus_id = "maple",
+        .init_name = "maple",
         .release = maple_bus_release,
 };
 
@@ -788,7 +795,8 @@ static int __init maple_bus_init(void)
 {
         int retval, i;
         struct maple_device *mdev[MAPLE_PORTS];
-        ctrl_outl(0, MAPLE_STATE);
+
+        ctrl_outl(0, MAPLE_ENABLE);
 
         retval = device_register(&maple_bus);
         if (retval)
@@ -798,36 +806,33 @@ static int __init maple_bus_init(void)
         if (retval)
                 goto cleanup_device;
 
-        retval = driver_register(&maple_dummy_driver.drv);
+        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) {
-                printk(KERN_INFO
-                       "Maple bus: Failed to allocate Maple DMA buffers\n");
+                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) {
-                printk(KERN_INFO
-                       "Maple bus: Failed to grab maple DMA IRQ\n");
+                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) {
-                printk(KERN_INFO "Maple bus: Failed to grab VBLANK IRQ\n");
+                dev_err(&maple_bus, "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);
+        maple_queue_cache = KMEM_CACHE(maple_buffer, SLAB_HWCACHE_ALIGN);
 
         if (!maple_queue_cache)
                 goto cleanup_bothirqs;
@@ -838,23 +843,23 @@ static int __init maple_bus_init(void)
         /* setup maple ports */
         for (i = 0; i < MAPLE_PORTS; i++) {
                 checked[i] = false;
+                empty[i] = false;
                 mdev[i] = maple_alloc_dev(i, 0);
-                baseunits[i] = mdev[i];
                 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;
         }
 
-        /* setup maplebus hardware */
-        maplebus_dma_reset();
-        /* initial detection */
+        maple_pnp_time = jiffies + HZ;
+        /* prepare initial queue */
         maple_send();
-        maple_pnp_time = jiffies;
-        printk(KERN_INFO "Maple bus core now registered.\n");
+        dev_info(&maple_bus, "bus core now registered\n");
 
         return 0;
 
@@ -871,7 +876,7 @@ cleanup_dma:
         free_pages((unsigned long) maple_sendbuf, MAPLE_DMA_PAGES);
 
 cleanup_basic:
-        driver_unregister(&maple_dummy_driver.drv);
+        driver_unregister(&maple_unsupported_device.drv);
 
 cleanup_bus:
         bus_unregister(&maple_bus_type);
@@ -880,7 +885,7 @@ cleanup_device:
         device_unregister(&maple_bus);
 
 cleanup:
-        printk(KERN_INFO "Maple bus registration failed\n");
+        printk(KERN_ERR "Maple bus registration failed\n");
         return retval;
 }
 /* Push init to later to ensure hardware gets detected */