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-rw-r--r--drivers/macintosh/adb.c898
1 files changed, 898 insertions, 0 deletions
diff --git a/drivers/macintosh/adb.c b/drivers/macintosh/adb.c
new file mode 100644
index 0000000000..057b0221f6
--- /dev/null
+++ b/drivers/macintosh/adb.c
@@ -0,0 +1,898 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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/signal.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/of.h>
+
+#include <linux/uaccess.h>
+#ifdef CONFIG_PPC
+#include <asm/machdep.h>
+#endif
+
+
+EXPORT_SYMBOL(adb_client_list);
+
+extern struct adb_driver via_macii_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_CUDA
+ &via_cuda_driver,
+#endif
+#ifdef CONFIG_ADB_IOP
+ &adb_iop_driver,
+#endif
+#ifdef CONFIG_ADB_PMU
+ &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, 1);
+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:
+ *
+ * https://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. */
+ 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(KERN_DEBUG "adb device [%d]: %d 0x%X\n", i,
+ adb_handler[i].original_address,
+ adb_handler[i].handler_id);
+ devmask |= 1 << i;
+ }
+ return devmask;
+}
+
+/*
+ * This kernel task handles ADB probing. It dies once probing is
+ * completed.
+ */
+static int
+adb_probe_task(void *x)
+{
+ pr_debug("adb: starting probe task...\n");
+ do_adb_reset_bus();
+ pr_debug("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) {
+ pr_warn("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) {
+ pr_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) {
+ pr_info("adb packet: ");
+ for (i = 0; i < nb; ++i)
+ pr_cont(" %x", buf[i]);
+ pr_cont(", 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);
+ if (ret)
+ pr_debug("adb handler change: [%d] 0x%X\n", address, new_id);
+ 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 || req->data[2] >= 16)
+ 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) {
+ 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);
+
+ 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;
+
+ 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)) {
+ pr_err("adb: unable to get major %d\n", ADB_MAJOR);
+ return;
+ }
+
+ adb_dev_class = class_create("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);
+}