Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / macintosh / adb.c
diff --git a/kernel/drivers/macintosh/adb.c b/kernel/drivers/macintosh/adb.c
new file mode 100644 (file)
index 0000000..226179b
--- /dev/null
@@ -0,0 +1,905 @@
+/*
+ * Device driver for the Apple Desktop Bus
+ * and the /dev/adb device on macintoshes.
+ *
+ * Copyright (C) 1996 Paul Mackerras.
+ *
+ * Modified to declare controllers as structures, added
+ * client notification of bus reset and handles PowerBook
+ * sleep, by Benjamin Herrenschmidt.
+ *
+ * To do:
+ *
+ * - /sys/bus/adb to list the devices and infos
+ * - more /dev/adb to allow userland to receive the
+ *   flow of auto-polling datas from a given device.
+ * - move bus probe to a kernel thread
+ */
+
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <linux/adb.h>
+#include <linux/cuda.h>
+#include <linux/pmu.h>
+#include <linux/notifier.h>
+#include <linux/wait.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/spinlock.h>
+#include <linux/completion.h>
+#include <linux/device.h>
+#include <linux/kthread.h>
+#include <linux/platform_device.h>
+#include <linux/mutex.h>
+
+#include <linux/uaccess.h>
+#ifdef CONFIG_PPC
+#include <asm/prom.h>
+#include <asm/machdep.h>
+#endif
+
+
+EXPORT_SYMBOL(adb_client_list);
+
+extern struct adb_driver via_macii_driver;
+extern struct adb_driver via_maciisi_driver;
+extern struct adb_driver via_cuda_driver;
+extern struct adb_driver adb_iop_driver;
+extern struct adb_driver via_pmu_driver;
+extern struct adb_driver macio_adb_driver;
+
+static DEFINE_MUTEX(adb_mutex);
+static struct adb_driver *adb_driver_list[] = {
+#ifdef CONFIG_ADB_MACII
+       &via_macii_driver,
+#endif
+#ifdef CONFIG_ADB_MACIISI
+       &via_maciisi_driver,
+#endif
+#ifdef CONFIG_ADB_CUDA
+       &via_cuda_driver,
+#endif
+#ifdef CONFIG_ADB_IOP
+       &adb_iop_driver,
+#endif
+#if defined(CONFIG_ADB_PMU) || defined(CONFIG_ADB_PMU68K)
+       &via_pmu_driver,
+#endif
+#ifdef CONFIG_ADB_MACIO
+       &macio_adb_driver,
+#endif
+       NULL
+};
+
+static struct class *adb_dev_class;
+
+static struct adb_driver *adb_controller;
+BLOCKING_NOTIFIER_HEAD(adb_client_list);
+static int adb_got_sleep;
+static int adb_inited;
+static DEFINE_SEMAPHORE(adb_probe_mutex);
+static int sleepy_trackpad;
+static int autopoll_devs;
+int __adb_probe_sync;
+
+static int adb_scan_bus(void);
+static int do_adb_reset_bus(void);
+static void adbdev_init(void);
+static int try_handler_change(int, int);
+
+static struct adb_handler {
+       void (*handler)(unsigned char *, int, int);
+       int original_address;
+       int handler_id;
+       int busy;
+} adb_handler[16];
+
+/*
+ * The adb_handler_mutex mutex protects all accesses to the original_address
+ * and handler_id fields of adb_handler[i] for all i, and changes to the
+ * handler field.
+ * Accesses to the handler field are protected by the adb_handler_lock
+ * rwlock.  It is held across all calls to any handler, so that by the
+ * time adb_unregister returns, we know that the old handler isn't being
+ * called.
+ */
+static DEFINE_MUTEX(adb_handler_mutex);
+static DEFINE_RWLOCK(adb_handler_lock);
+
+#if 0
+static void printADBreply(struct adb_request *req)
+{
+        int i;
+
+        printk("adb reply (%d)", req->reply_len);
+        for(i = 0; i < req->reply_len; i++)
+                printk(" %x", req->reply[i]);
+        printk("\n");
+
+}
+#endif
+
+static int adb_scan_bus(void)
+{
+       int i, highFree=0, noMovement;
+       int devmask = 0;
+       struct adb_request req;
+       
+       /* assumes adb_handler[] is all zeroes at this point */
+       for (i = 1; i < 16; i++) {
+               /* see if there is anything at address i */
+               adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1,
+                            (i << 4) | 0xf);
+               if (req.reply_len > 1)
+                       /* one or more devices at this address */
+                       adb_handler[i].original_address = i;
+               else if (i > highFree)
+                       highFree = i;
+       }
+
+       /* Note we reset noMovement to 0 each time we move a device */
+       for (noMovement = 1; noMovement < 2 && highFree > 0; noMovement++) {
+               for (i = 1; i < 16; i++) {
+                       if (adb_handler[i].original_address == 0)
+                               continue;
+                       /*
+                        * Send a "talk register 3" command to address i
+                        * to provoke a collision if there is more than
+                        * one device at this address.
+                        */
+                       adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1,
+                                   (i << 4) | 0xf);
+                       /*
+                        * Move the device(s) which didn't detect a
+                        * collision to address `highFree'.  Hopefully
+                        * this only moves one device.
+                        */
+                       adb_request(&req, NULL, ADBREQ_SYNC, 3,
+                                   (i<< 4) | 0xb, (highFree | 0x60), 0xfe);
+                       /*
+                        * See if anybody actually moved. This is suggested
+                        * by HW TechNote 01:
+                        *
+                        * http://developer.apple.com/technotes/hw/hw_01.html
+                        */
+                       adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1,
+                                   (highFree << 4) | 0xf);
+                       if (req.reply_len <= 1) continue;
+                       /*
+                        * Test whether there are any device(s) left
+                        * at address i.
+                        */
+                       adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1,
+                                   (i << 4) | 0xf);
+                       if (req.reply_len > 1) {
+                               /*
+                                * There are still one or more devices
+                                * left at address i.  Register the one(s)
+                                * we moved to `highFree', and find a new
+                                * value for highFree.
+                                */
+                               adb_handler[highFree].original_address =
+                                       adb_handler[i].original_address;
+                               while (highFree > 0 &&
+                                      adb_handler[highFree].original_address)
+                                       highFree--;
+                               if (highFree <= 0)
+                                       break;
+
+                               noMovement = 0;
+                       } else {
+                               /*
+                                * No devices left at address i; move the
+                                * one(s) we moved to `highFree' back to i.
+                                */
+                               adb_request(&req, NULL, ADBREQ_SYNC, 3,
+                                           (highFree << 4) | 0xb,
+                                           (i | 0x60), 0xfe);
+                       }
+               }       
+       }
+
+       /* Now fill in the handler_id field of the adb_handler entries. */
+       printk(KERN_DEBUG "adb devices:");
+       for (i = 1; i < 16; i++) {
+               if (adb_handler[i].original_address == 0)
+                       continue;
+               adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1,
+                           (i << 4) | 0xf);
+               adb_handler[i].handler_id = req.reply[2];
+               printk(" [%d]: %d %x", i, adb_handler[i].original_address,
+                      adb_handler[i].handler_id);
+               devmask |= 1 << i;
+       }
+       printk("\n");
+       return devmask;
+}
+
+/*
+ * This kernel task handles ADB probing. It dies once probing is
+ * completed.
+ */
+static int
+adb_probe_task(void *x)
+{
+       printk(KERN_INFO "adb: starting probe task...\n");
+       do_adb_reset_bus();
+       printk(KERN_INFO "adb: finished probe task...\n");
+
+       up(&adb_probe_mutex);
+
+       return 0;
+}
+
+static void
+__adb_probe_task(struct work_struct *bullshit)
+{
+       kthread_run(adb_probe_task, NULL, "kadbprobe");
+}
+
+static DECLARE_WORK(adb_reset_work, __adb_probe_task);
+
+int
+adb_reset_bus(void)
+{
+       if (__adb_probe_sync) {
+               do_adb_reset_bus();
+               return 0;
+       }
+
+       down(&adb_probe_mutex);
+       schedule_work(&adb_reset_work);
+       return 0;
+}
+
+#ifdef CONFIG_PM
+/*
+ * notify clients before sleep
+ */
+static int __adb_suspend(struct platform_device *dev, pm_message_t state)
+{
+       adb_got_sleep = 1;
+       /* We need to get a lock on the probe thread */
+       down(&adb_probe_mutex);
+       /* Stop autopoll */
+       if (adb_controller->autopoll)
+               adb_controller->autopoll(0);
+       blocking_notifier_call_chain(&adb_client_list, ADB_MSG_POWERDOWN, NULL);
+
+       return 0;
+}
+
+static int adb_suspend(struct device *dev)
+{
+       return __adb_suspend(to_platform_device(dev), PMSG_SUSPEND);
+}
+
+static int adb_freeze(struct device *dev)
+{
+       return __adb_suspend(to_platform_device(dev), PMSG_FREEZE);
+}
+
+static int adb_poweroff(struct device *dev)
+{
+       return __adb_suspend(to_platform_device(dev), PMSG_HIBERNATE);
+}
+
+/*
+ * reset bus after sleep
+ */
+static int __adb_resume(struct platform_device *dev)
+{
+       adb_got_sleep = 0;
+       up(&adb_probe_mutex);
+       adb_reset_bus();
+
+       return 0;
+}
+
+static int adb_resume(struct device *dev)
+{
+       return __adb_resume(to_platform_device(dev));
+}
+#endif /* CONFIG_PM */
+
+static int __init adb_init(void)
+{
+       struct adb_driver *driver;
+       int i;
+
+#ifdef CONFIG_PPC32
+       if (!machine_is(chrp) && !machine_is(powermac))
+               return 0;
+#endif
+#ifdef CONFIG_MAC
+       if (!MACH_IS_MAC)
+               return 0;
+#endif
+
+       /* xmon may do early-init */
+       if (adb_inited)
+               return 0;
+       adb_inited = 1;
+               
+       adb_controller = NULL;
+
+       i = 0;
+       while ((driver = adb_driver_list[i++]) != NULL) {
+               if (!driver->probe()) {
+                       adb_controller = driver;
+                       break;
+               }
+       }
+       if (adb_controller != NULL && adb_controller->init &&
+           adb_controller->init())
+               adb_controller = NULL;
+       if (adb_controller == NULL) {
+               printk(KERN_WARNING "Warning: no ADB interface detected\n");
+       } else {
+#ifdef CONFIG_PPC
+               if (of_machine_is_compatible("AAPL,PowerBook1998") ||
+                       of_machine_is_compatible("PowerBook1,1"))
+                       sleepy_trackpad = 1;
+#endif /* CONFIG_PPC */
+
+               adbdev_init();
+               adb_reset_bus();
+       }
+       return 0;
+}
+
+device_initcall(adb_init);
+
+static int
+do_adb_reset_bus(void)
+{
+       int ret;
+       
+       if (adb_controller == NULL)
+               return -ENXIO;
+               
+       if (adb_controller->autopoll)
+               adb_controller->autopoll(0);
+
+       blocking_notifier_call_chain(&adb_client_list,
+               ADB_MSG_PRE_RESET, NULL);
+
+       if (sleepy_trackpad) {
+               /* Let the trackpad settle down */
+               msleep(500);
+       }
+
+       mutex_lock(&adb_handler_mutex);
+       write_lock_irq(&adb_handler_lock);
+       memset(adb_handler, 0, sizeof(adb_handler));
+       write_unlock_irq(&adb_handler_lock);
+
+       /* That one is still a bit synchronous, oh well... */
+       if (adb_controller->reset_bus)
+               ret = adb_controller->reset_bus();
+       else
+               ret = 0;
+
+       if (sleepy_trackpad) {
+               /* Let the trackpad settle down */
+               msleep(1500);
+       }
+
+       if (!ret) {
+               autopoll_devs = adb_scan_bus();
+               if (adb_controller->autopoll)
+                       adb_controller->autopoll(autopoll_devs);
+       }
+       mutex_unlock(&adb_handler_mutex);
+
+       blocking_notifier_call_chain(&adb_client_list,
+               ADB_MSG_POST_RESET, NULL);
+       
+       return ret;
+}
+
+void
+adb_poll(void)
+{
+       if ((adb_controller == NULL)||(adb_controller->poll == NULL))
+               return;
+       adb_controller->poll();
+}
+EXPORT_SYMBOL(adb_poll);
+
+static void adb_sync_req_done(struct adb_request *req)
+{
+       struct completion *comp = req->arg;
+
+       complete(comp);
+}
+
+int
+adb_request(struct adb_request *req, void (*done)(struct adb_request *),
+           int flags, int nbytes, ...)
+{
+       va_list list;
+       int i;
+       int rc;
+       struct completion comp;
+
+       if ((adb_controller == NULL) || (adb_controller->send_request == NULL))
+               return -ENXIO;
+       if (nbytes < 1)
+               return -EINVAL;
+
+       req->nbytes = nbytes+1;
+       req->done = done;
+       req->reply_expected = flags & ADBREQ_REPLY;
+       req->data[0] = ADB_PACKET;
+       va_start(list, nbytes);
+       for (i = 0; i < nbytes; ++i)
+               req->data[i+1] = va_arg(list, int);
+       va_end(list);
+
+       if (flags & ADBREQ_NOSEND)
+               return 0;
+
+       /* Synchronous requests block using an on-stack completion */
+       if (flags & ADBREQ_SYNC) {
+               WARN_ON(done);
+               req->done = adb_sync_req_done;
+               req->arg = &comp;
+               init_completion(&comp);
+       }
+
+       rc = adb_controller->send_request(req, 0);
+
+       if ((flags & ADBREQ_SYNC) && !rc && !req->complete)
+               wait_for_completion(&comp);
+
+       return rc;
+}
+EXPORT_SYMBOL(adb_request);
+
+ /* Ultimately this should return the number of devices with
+    the given default id.
+    And it does it now ! Note: changed behaviour: This function
+    will now register if default_id _and_ handler_id both match
+    but handler_id can be left to 0 to match with default_id only.
+    When handler_id is set, this function will try to adjust
+    the handler_id id it doesn't match. */
+int
+adb_register(int default_id, int handler_id, struct adb_ids *ids,
+            void (*handler)(unsigned char *, int, int))
+{
+       int i;
+
+       mutex_lock(&adb_handler_mutex);
+       ids->nids = 0;
+       for (i = 1; i < 16; i++) {
+               if ((adb_handler[i].original_address == default_id) &&
+                   (!handler_id || (handler_id == adb_handler[i].handler_id) || 
+                   try_handler_change(i, handler_id))) {
+                       if (adb_handler[i].handler != 0) {
+                               printk(KERN_ERR
+                                      "Two handlers for ADB device %d\n",
+                                      default_id);
+                               continue;
+                       }
+                       write_lock_irq(&adb_handler_lock);
+                       adb_handler[i].handler = handler;
+                       write_unlock_irq(&adb_handler_lock);
+                       ids->id[ids->nids++] = i;
+               }
+       }
+       mutex_unlock(&adb_handler_mutex);
+       return ids->nids;
+}
+EXPORT_SYMBOL(adb_register);
+
+int
+adb_unregister(int index)
+{
+       int ret = -ENODEV;
+
+       mutex_lock(&adb_handler_mutex);
+       write_lock_irq(&adb_handler_lock);
+       if (adb_handler[index].handler) {
+               while(adb_handler[index].busy) {
+                       write_unlock_irq(&adb_handler_lock);
+                       yield();
+                       write_lock_irq(&adb_handler_lock);
+               }
+               ret = 0;
+               adb_handler[index].handler = NULL;
+       }
+       write_unlock_irq(&adb_handler_lock);
+       mutex_unlock(&adb_handler_mutex);
+       return ret;
+}
+EXPORT_SYMBOL(adb_unregister);
+
+void
+adb_input(unsigned char *buf, int nb, int autopoll)
+{
+       int i, id;
+       static int dump_adb_input;
+       unsigned long flags;
+       
+       void (*handler)(unsigned char *, int, int);
+
+       /* We skip keystrokes and mouse moves when the sleep process
+        * has been started. We stop autopoll, but this is another security
+        */
+       if (adb_got_sleep)
+               return;
+               
+       id = buf[0] >> 4;
+       if (dump_adb_input) {
+               printk(KERN_INFO "adb packet: ");
+               for (i = 0; i < nb; ++i)
+                       printk(" %x", buf[i]);
+               printk(", id = %d\n", id);
+       }
+       write_lock_irqsave(&adb_handler_lock, flags);
+       handler = adb_handler[id].handler;
+       if (handler != NULL)
+               adb_handler[id].busy = 1;
+       write_unlock_irqrestore(&adb_handler_lock, flags);
+       if (handler != NULL) {
+               (*handler)(buf, nb, autopoll);
+               wmb();
+               adb_handler[id].busy = 0;
+       }
+               
+}
+
+/* Try to change handler to new_id. Will return 1 if successful. */
+static int try_handler_change(int address, int new_id)
+{
+       struct adb_request req;
+
+       if (adb_handler[address].handler_id == new_id)
+           return 1;
+       adb_request(&req, NULL, ADBREQ_SYNC, 3,
+           ADB_WRITEREG(address, 3), address | 0x20, new_id);
+       adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1,
+           ADB_READREG(address, 3));
+       if (req.reply_len < 2)
+           return 0;
+       if (req.reply[2] != new_id)
+           return 0;
+       adb_handler[address].handler_id = req.reply[2];
+
+       return 1;
+}
+
+int
+adb_try_handler_change(int address, int new_id)
+{
+       int ret;
+
+       mutex_lock(&adb_handler_mutex);
+       ret = try_handler_change(address, new_id);
+       mutex_unlock(&adb_handler_mutex);
+       return ret;
+}
+EXPORT_SYMBOL(adb_try_handler_change);
+
+int
+adb_get_infos(int address, int *original_address, int *handler_id)
+{
+       mutex_lock(&adb_handler_mutex);
+       *original_address = adb_handler[address].original_address;
+       *handler_id = adb_handler[address].handler_id;
+       mutex_unlock(&adb_handler_mutex);
+
+       return (*original_address != 0);
+}
+
+
+/*
+ * /dev/adb device driver.
+ */
+
+#define ADB_MAJOR      56      /* major number for /dev/adb */
+
+struct adbdev_state {
+       spinlock_t      lock;
+       atomic_t        n_pending;
+       struct adb_request *completed;
+       wait_queue_head_t wait_queue;
+       int             inuse;
+};
+
+static void adb_write_done(struct adb_request *req)
+{
+       struct adbdev_state *state = (struct adbdev_state *) req->arg;
+       unsigned long flags;
+
+       if (!req->complete) {
+               req->reply_len = 0;
+               req->complete = 1;
+       }
+       spin_lock_irqsave(&state->lock, flags);
+       atomic_dec(&state->n_pending);
+       if (!state->inuse) {
+               kfree(req);
+               if (atomic_read(&state->n_pending) == 0) {
+                       spin_unlock_irqrestore(&state->lock, flags);
+                       kfree(state);
+                       return;
+               }
+       } else {
+               struct adb_request **ap = &state->completed;
+               while (*ap != NULL)
+                       ap = &(*ap)->next;
+               req->next = NULL;
+               *ap = req;
+               wake_up_interruptible(&state->wait_queue);
+       }
+       spin_unlock_irqrestore(&state->lock, flags);
+}
+
+static int
+do_adb_query(struct adb_request *req)
+{
+       int     ret = -EINVAL;
+
+       switch(req->data[1]) {
+       case ADB_QUERY_GETDEVINFO:
+               if (req->nbytes < 3)
+                       break;
+               mutex_lock(&adb_handler_mutex);
+               req->reply[0] = adb_handler[req->data[2]].original_address;
+               req->reply[1] = adb_handler[req->data[2]].handler_id;
+               mutex_unlock(&adb_handler_mutex);
+               req->complete = 1;
+               req->reply_len = 2;
+               adb_write_done(req);
+               ret = 0;
+               break;
+       }
+       return ret;
+}
+
+static int adb_open(struct inode *inode, struct file *file)
+{
+       struct adbdev_state *state;
+       int ret = 0;
+
+       mutex_lock(&adb_mutex);
+       if (iminor(inode) > 0 || adb_controller == NULL) {
+               ret = -ENXIO;
+               goto out;
+       }
+       state = kmalloc(sizeof(struct adbdev_state), GFP_KERNEL);
+       if (state == 0) {
+               ret = -ENOMEM;
+               goto out;
+       }
+       file->private_data = state;
+       spin_lock_init(&state->lock);
+       atomic_set(&state->n_pending, 0);
+       state->completed = NULL;
+       init_waitqueue_head(&state->wait_queue);
+       state->inuse = 1;
+
+out:
+       mutex_unlock(&adb_mutex);
+       return ret;
+}
+
+static int adb_release(struct inode *inode, struct file *file)
+{
+       struct adbdev_state *state = file->private_data;
+       unsigned long flags;
+
+       mutex_lock(&adb_mutex);
+       if (state) {
+               file->private_data = NULL;
+               spin_lock_irqsave(&state->lock, flags);
+               if (atomic_read(&state->n_pending) == 0
+                   && state->completed == NULL) {
+                       spin_unlock_irqrestore(&state->lock, flags);
+                       kfree(state);
+               } else {
+                       state->inuse = 0;
+                       spin_unlock_irqrestore(&state->lock, flags);
+               }
+       }
+       mutex_unlock(&adb_mutex);
+       return 0;
+}
+
+static ssize_t adb_read(struct file *file, char __user *buf,
+                       size_t count, loff_t *ppos)
+{
+       int ret = 0;
+       struct adbdev_state *state = file->private_data;
+       struct adb_request *req;
+       DECLARE_WAITQUEUE(wait, current);
+       unsigned long flags;
+
+       if (count < 2)
+               return -EINVAL;
+       if (count > sizeof(req->reply))
+               count = sizeof(req->reply);
+       if (!access_ok(VERIFY_WRITE, buf, count))
+               return -EFAULT;
+
+       req = NULL;
+       spin_lock_irqsave(&state->lock, flags);
+       add_wait_queue(&state->wait_queue, &wait);
+       set_current_state(TASK_INTERRUPTIBLE);
+
+       for (;;) {
+               req = state->completed;
+               if (req != NULL)
+                       state->completed = req->next;
+               else if (atomic_read(&state->n_pending) == 0)
+                       ret = -EIO;
+               if (req != NULL || ret != 0)
+                       break;
+               
+               if (file->f_flags & O_NONBLOCK) {
+                       ret = -EAGAIN;
+                       break;
+               }
+               if (signal_pending(current)) {
+                       ret = -ERESTARTSYS;
+                       break;
+               }
+               spin_unlock_irqrestore(&state->lock, flags);
+               schedule();
+               spin_lock_irqsave(&state->lock, flags);
+       }
+
+       set_current_state(TASK_RUNNING);
+       remove_wait_queue(&state->wait_queue, &wait);
+       spin_unlock_irqrestore(&state->lock, flags);
+       
+       if (ret)
+               return ret;
+
+       ret = req->reply_len;
+       if (ret > count)
+               ret = count;
+       if (ret > 0 && copy_to_user(buf, req->reply, ret))
+               ret = -EFAULT;
+
+       kfree(req);
+       return ret;
+}
+
+static ssize_t adb_write(struct file *file, const char __user *buf,
+                        size_t count, loff_t *ppos)
+{
+       int ret/*, i*/;
+       struct adbdev_state *state = file->private_data;
+       struct adb_request *req;
+
+       if (count < 2 || count > sizeof(req->data))
+               return -EINVAL;
+       if (adb_controller == NULL)
+               return -ENXIO;
+       if (!access_ok(VERIFY_READ, buf, count))
+               return -EFAULT;
+
+       req = kmalloc(sizeof(struct adb_request),
+                                            GFP_KERNEL);
+       if (req == NULL)
+               return -ENOMEM;
+
+       req->nbytes = count;
+       req->done = adb_write_done;
+       req->arg = (void *) state;
+       req->complete = 0;
+       
+       ret = -EFAULT;
+       if (copy_from_user(req->data, buf, count))
+               goto out;
+
+       atomic_inc(&state->n_pending);
+
+       /* If a probe is in progress or we are sleeping, wait for it to complete */
+       down(&adb_probe_mutex);
+
+       /* Queries are special requests sent to the ADB driver itself */
+       if (req->data[0] == ADB_QUERY) {
+               if (count > 1)
+                       ret = do_adb_query(req);
+               else
+                       ret = -EINVAL;
+               up(&adb_probe_mutex);
+       }
+       /* Special case for ADB_BUSRESET request, all others are sent to
+          the controller */
+       else if ((req->data[0] == ADB_PACKET) && (count > 1)
+               && (req->data[1] == ADB_BUSRESET)) {
+               ret = do_adb_reset_bus();
+               up(&adb_probe_mutex);
+               atomic_dec(&state->n_pending);
+               if (ret == 0)
+                       ret = count;
+               goto out;
+       } else {        
+               req->reply_expected = ((req->data[1] & 0xc) == 0xc);
+               if (adb_controller && adb_controller->send_request)
+                       ret = adb_controller->send_request(req, 0);
+               else
+                       ret = -ENXIO;
+               up(&adb_probe_mutex);
+       }
+
+       if (ret != 0) {
+               atomic_dec(&state->n_pending);
+               goto out;
+       }
+       return count;
+
+out:
+       kfree(req);
+       return ret;
+}
+
+static const struct file_operations adb_fops = {
+       .owner          = THIS_MODULE,
+       .llseek         = no_llseek,
+       .read           = adb_read,
+       .write          = adb_write,
+       .open           = adb_open,
+       .release        = adb_release,
+};
+
+#ifdef CONFIG_PM
+static const struct dev_pm_ops adb_dev_pm_ops = {
+       .suspend = adb_suspend,
+       .resume = adb_resume,
+       /* Hibernate hooks */
+       .freeze = adb_freeze,
+       .thaw = adb_resume,
+       .poweroff = adb_poweroff,
+       .restore = adb_resume,
+};
+#endif
+
+static struct platform_driver adb_pfdrv = {
+       .driver = {
+               .name = "adb",
+#ifdef CONFIG_PM
+               .pm = &adb_dev_pm_ops,
+#endif
+       },
+};
+
+static struct platform_device adb_pfdev = {
+       .name = "adb",
+};
+
+static int __init
+adb_dummy_probe(struct platform_device *dev)
+{
+       if (dev == &adb_pfdev)
+               return 0;
+       return -ENODEV;
+}
+
+static void __init
+adbdev_init(void)
+{
+       if (register_chrdev(ADB_MAJOR, "adb", &adb_fops)) {
+               printk(KERN_ERR "adb: unable to get major %d\n", ADB_MAJOR);
+               return;
+       }
+
+       adb_dev_class = class_create(THIS_MODULE, "adb");
+       if (IS_ERR(adb_dev_class))
+               return;
+       device_create(adb_dev_class, NULL, MKDEV(ADB_MAJOR, 0), NULL, "adb");
+
+       platform_device_register(&adb_pfdev);
+       platform_driver_probe(&adb_pfdrv, adb_dummy_probe);
+}