File-copy from v4.4.100
This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Please refer to that tree for all history prior to this point.
Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/drivers/input/input.c b/drivers/input/input.c
new file mode 100644
index 0000000..8806059
--- /dev/null
+++ b/drivers/input/input.c
@@ -0,0 +1,2454 @@
+/*
+ * The input core
+ *
+ * Copyright (c) 1999-2002 Vojtech Pavlik
+ */
+
+/*
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ */
+
+#define pr_fmt(fmt) KBUILD_BASENAME ": " fmt
+
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/idr.h>
+#include <linux/input/mt.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/random.h>
+#include <linux/major.h>
+#include <linux/proc_fs.h>
+#include <linux/sched.h>
+#include <linux/seq_file.h>
+#include <linux/poll.h>
+#include <linux/device.h>
+#include <linux/mutex.h>
+#include <linux/rcupdate.h>
+#include "input-compat.h"
+
+MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
+MODULE_DESCRIPTION("Input core");
+MODULE_LICENSE("GPL");
+
+#define INPUT_MAX_CHAR_DEVICES 1024
+#define INPUT_FIRST_DYNAMIC_DEV 256
+static DEFINE_IDA(input_ida);
+
+static LIST_HEAD(input_dev_list);
+static LIST_HEAD(input_handler_list);
+
+/*
+ * input_mutex protects access to both input_dev_list and input_handler_list.
+ * This also causes input_[un]register_device and input_[un]register_handler
+ * be mutually exclusive which simplifies locking in drivers implementing
+ * input handlers.
+ */
+static DEFINE_MUTEX(input_mutex);
+
+static const struct input_value input_value_sync = { EV_SYN, SYN_REPORT, 1 };
+
+static inline int is_event_supported(unsigned int code,
+ unsigned long *bm, unsigned int max)
+{
+ return code <= max && test_bit(code, bm);
+}
+
+static int input_defuzz_abs_event(int value, int old_val, int fuzz)
+{
+ if (fuzz) {
+ if (value > old_val - fuzz / 2 && value < old_val + fuzz / 2)
+ return old_val;
+
+ if (value > old_val - fuzz && value < old_val + fuzz)
+ return (old_val * 3 + value) / 4;
+
+ if (value > old_val - fuzz * 2 && value < old_val + fuzz * 2)
+ return (old_val + value) / 2;
+ }
+
+ return value;
+}
+
+static void input_start_autorepeat(struct input_dev *dev, int code)
+{
+ if (test_bit(EV_REP, dev->evbit) &&
+ dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] &&
+ dev->timer.data) {
+ dev->repeat_key = code;
+ mod_timer(&dev->timer,
+ jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]));
+ }
+}
+
+static void input_stop_autorepeat(struct input_dev *dev)
+{
+ del_timer(&dev->timer);
+}
+
+/*
+ * Pass event first through all filters and then, if event has not been
+ * filtered out, through all open handles. This function is called with
+ * dev->event_lock held and interrupts disabled.
+ */
+static unsigned int input_to_handler(struct input_handle *handle,
+ struct input_value *vals, unsigned int count)
+{
+ struct input_handler *handler = handle->handler;
+ struct input_value *end = vals;
+ struct input_value *v;
+
+ if (handler->filter) {
+ for (v = vals; v != vals + count; v++) {
+ if (handler->filter(handle, v->type, v->code, v->value))
+ continue;
+ if (end != v)
+ *end = *v;
+ end++;
+ }
+ count = end - vals;
+ }
+
+ if (!count)
+ return 0;
+
+ if (handler->events)
+ handler->events(handle, vals, count);
+ else if (handler->event)
+ for (v = vals; v != vals + count; v++)
+ handler->event(handle, v->type, v->code, v->value);
+
+ return count;
+}
+
+/*
+ * Pass values first through all filters and then, if event has not been
+ * filtered out, through all open handles. This function is called with
+ * dev->event_lock held and interrupts disabled.
+ */
+static void input_pass_values(struct input_dev *dev,
+ struct input_value *vals, unsigned int count)
+{
+ struct input_handle *handle;
+ struct input_value *v;
+
+ if (!count)
+ return;
+
+ rcu_read_lock();
+
+ handle = rcu_dereference(dev->grab);
+ if (handle) {
+ count = input_to_handler(handle, vals, count);
+ } else {
+ list_for_each_entry_rcu(handle, &dev->h_list, d_node)
+ if (handle->open) {
+ count = input_to_handler(handle, vals, count);
+ if (!count)
+ break;
+ }
+ }
+
+ rcu_read_unlock();
+
+ add_input_randomness(vals->type, vals->code, vals->value);
+
+ /* trigger auto repeat for key events */
+ if (test_bit(EV_REP, dev->evbit) && test_bit(EV_KEY, dev->evbit)) {
+ for (v = vals; v != vals + count; v++) {
+ if (v->type == EV_KEY && v->value != 2) {
+ if (v->value)
+ input_start_autorepeat(dev, v->code);
+ else
+ input_stop_autorepeat(dev);
+ }
+ }
+ }
+}
+
+static void input_pass_event(struct input_dev *dev,
+ unsigned int type, unsigned int code, int value)
+{
+ struct input_value vals[] = { { type, code, value } };
+
+ input_pass_values(dev, vals, ARRAY_SIZE(vals));
+}
+
+/*
+ * Generate software autorepeat event. Note that we take
+ * dev->event_lock here to avoid racing with input_event
+ * which may cause keys get "stuck".
+ */
+static void input_repeat_key(unsigned long data)
+{
+ struct input_dev *dev = (void *) data;
+ unsigned long flags;
+
+ spin_lock_irqsave(&dev->event_lock, flags);
+
+ if (test_bit(dev->repeat_key, dev->key) &&
+ is_event_supported(dev->repeat_key, dev->keybit, KEY_MAX)) {
+ struct input_value vals[] = {
+ { EV_KEY, dev->repeat_key, 2 },
+ input_value_sync
+ };
+
+ input_pass_values(dev, vals, ARRAY_SIZE(vals));
+
+ if (dev->rep[REP_PERIOD])
+ mod_timer(&dev->timer, jiffies +
+ msecs_to_jiffies(dev->rep[REP_PERIOD]));
+ }
+
+ spin_unlock_irqrestore(&dev->event_lock, flags);
+}
+
+#define INPUT_IGNORE_EVENT 0
+#define INPUT_PASS_TO_HANDLERS 1
+#define INPUT_PASS_TO_DEVICE 2
+#define INPUT_SLOT 4
+#define INPUT_FLUSH 8
+#define INPUT_PASS_TO_ALL (INPUT_PASS_TO_HANDLERS | INPUT_PASS_TO_DEVICE)
+
+static int input_handle_abs_event(struct input_dev *dev,
+ unsigned int code, int *pval)
+{
+ struct input_mt *mt = dev->mt;
+ bool is_mt_event;
+ int *pold;
+
+ if (code == ABS_MT_SLOT) {
+ /*
+ * "Stage" the event; we'll flush it later, when we
+ * get actual touch data.
+ */
+ if (mt && *pval >= 0 && *pval < mt->num_slots)
+ mt->slot = *pval;
+
+ return INPUT_IGNORE_EVENT;
+ }
+
+ is_mt_event = input_is_mt_value(code);
+
+ if (!is_mt_event) {
+ pold = &dev->absinfo[code].value;
+ } else if (mt) {
+ pold = &mt->slots[mt->slot].abs[code - ABS_MT_FIRST];
+ } else {
+ /*
+ * Bypass filtering for multi-touch events when
+ * not employing slots.
+ */
+ pold = NULL;
+ }
+
+ if (pold) {
+ *pval = input_defuzz_abs_event(*pval, *pold,
+ dev->absinfo[code].fuzz);
+ if (*pold == *pval)
+ return INPUT_IGNORE_EVENT;
+
+ *pold = *pval;
+ }
+
+ /* Flush pending "slot" event */
+ if (is_mt_event && mt && mt->slot != input_abs_get_val(dev, ABS_MT_SLOT)) {
+ input_abs_set_val(dev, ABS_MT_SLOT, mt->slot);
+ return INPUT_PASS_TO_HANDLERS | INPUT_SLOT;
+ }
+
+ return INPUT_PASS_TO_HANDLERS;
+}
+
+static int input_get_disposition(struct input_dev *dev,
+ unsigned int type, unsigned int code, int *pval)
+{
+ int disposition = INPUT_IGNORE_EVENT;
+ int value = *pval;
+
+ switch (type) {
+
+ case EV_SYN:
+ switch (code) {
+ case SYN_CONFIG:
+ disposition = INPUT_PASS_TO_ALL;
+ break;
+
+ case SYN_REPORT:
+ disposition = INPUT_PASS_TO_HANDLERS | INPUT_FLUSH;
+ break;
+ case SYN_MT_REPORT:
+ disposition = INPUT_PASS_TO_HANDLERS;
+ break;
+ }
+ break;
+
+ case EV_KEY:
+ if (is_event_supported(code, dev->keybit, KEY_MAX)) {
+
+ /* auto-repeat bypasses state updates */
+ if (value == 2) {
+ disposition = INPUT_PASS_TO_HANDLERS;
+ break;
+ }
+
+ if (!!test_bit(code, dev->key) != !!value) {
+
+ __change_bit(code, dev->key);
+ disposition = INPUT_PASS_TO_HANDLERS;
+ }
+ }
+ break;
+
+ case EV_SW:
+ if (is_event_supported(code, dev->swbit, SW_MAX) &&
+ !!test_bit(code, dev->sw) != !!value) {
+
+ __change_bit(code, dev->sw);
+ disposition = INPUT_PASS_TO_HANDLERS;
+ }
+ break;
+
+ case EV_ABS:
+ if (is_event_supported(code, dev->absbit, ABS_MAX))
+ disposition = input_handle_abs_event(dev, code, &value);
+
+ break;
+
+ case EV_REL:
+ if (is_event_supported(code, dev->relbit, REL_MAX) && value)
+ disposition = INPUT_PASS_TO_HANDLERS;
+
+ break;
+
+ case EV_MSC:
+ if (is_event_supported(code, dev->mscbit, MSC_MAX))
+ disposition = INPUT_PASS_TO_ALL;
+
+ break;
+
+ case EV_LED:
+ if (is_event_supported(code, dev->ledbit, LED_MAX) &&
+ !!test_bit(code, dev->led) != !!value) {
+
+ __change_bit(code, dev->led);
+ disposition = INPUT_PASS_TO_ALL;
+ }
+ break;
+
+ case EV_SND:
+ if (is_event_supported(code, dev->sndbit, SND_MAX)) {
+
+ if (!!test_bit(code, dev->snd) != !!value)
+ __change_bit(code, dev->snd);
+ disposition = INPUT_PASS_TO_ALL;
+ }
+ break;
+
+ case EV_REP:
+ if (code <= REP_MAX && value >= 0 && dev->rep[code] != value) {
+ dev->rep[code] = value;
+ disposition = INPUT_PASS_TO_ALL;
+ }
+ break;
+
+ case EV_FF:
+ if (value >= 0)
+ disposition = INPUT_PASS_TO_ALL;
+ break;
+
+ case EV_PWR:
+ disposition = INPUT_PASS_TO_ALL;
+ break;
+ }
+
+ *pval = value;
+ return disposition;
+}
+
+static void input_handle_event(struct input_dev *dev,
+ unsigned int type, unsigned int code, int value)
+{
+ int disposition;
+
+ disposition = input_get_disposition(dev, type, code, &value);
+
+ if ((disposition & INPUT_PASS_TO_DEVICE) && dev->event)
+ dev->event(dev, type, code, value);
+
+ if (!dev->vals)
+ return;
+
+ if (disposition & INPUT_PASS_TO_HANDLERS) {
+ struct input_value *v;
+
+ if (disposition & INPUT_SLOT) {
+ v = &dev->vals[dev->num_vals++];
+ v->type = EV_ABS;
+ v->code = ABS_MT_SLOT;
+ v->value = dev->mt->slot;
+ }
+
+ v = &dev->vals[dev->num_vals++];
+ v->type = type;
+ v->code = code;
+ v->value = value;
+ }
+
+ if (disposition & INPUT_FLUSH) {
+ if (dev->num_vals >= 2)
+ input_pass_values(dev, dev->vals, dev->num_vals);
+ dev->num_vals = 0;
+ } else if (dev->num_vals >= dev->max_vals - 2) {
+ dev->vals[dev->num_vals++] = input_value_sync;
+ input_pass_values(dev, dev->vals, dev->num_vals);
+ dev->num_vals = 0;
+ }
+
+}
+
+/**
+ * input_event() - report new input event
+ * @dev: device that generated the event
+ * @type: type of the event
+ * @code: event code
+ * @value: value of the event
+ *
+ * This function should be used by drivers implementing various input
+ * devices to report input events. See also input_inject_event().
+ *
+ * NOTE: input_event() may be safely used right after input device was
+ * allocated with input_allocate_device(), even before it is registered
+ * with input_register_device(), but the event will not reach any of the
+ * input handlers. Such early invocation of input_event() may be used
+ * to 'seed' initial state of a switch or initial position of absolute
+ * axis, etc.
+ */
+void input_event(struct input_dev *dev,
+ unsigned int type, unsigned int code, int value)
+{
+ unsigned long flags;
+
+ if (is_event_supported(type, dev->evbit, EV_MAX)) {
+
+ spin_lock_irqsave(&dev->event_lock, flags);
+ input_handle_event(dev, type, code, value);
+ spin_unlock_irqrestore(&dev->event_lock, flags);
+ }
+}
+EXPORT_SYMBOL(input_event);
+
+/**
+ * input_inject_event() - send input event from input handler
+ * @handle: input handle to send event through
+ * @type: type of the event
+ * @code: event code
+ * @value: value of the event
+ *
+ * Similar to input_event() but will ignore event if device is
+ * "grabbed" and handle injecting event is not the one that owns
+ * the device.
+ */
+void input_inject_event(struct input_handle *handle,
+ unsigned int type, unsigned int code, int value)
+{
+ struct input_dev *dev = handle->dev;
+ struct input_handle *grab;
+ unsigned long flags;
+
+ if (is_event_supported(type, dev->evbit, EV_MAX)) {
+ spin_lock_irqsave(&dev->event_lock, flags);
+
+ rcu_read_lock();
+ grab = rcu_dereference(dev->grab);
+ if (!grab || grab == handle)
+ input_handle_event(dev, type, code, value);
+ rcu_read_unlock();
+
+ spin_unlock_irqrestore(&dev->event_lock, flags);
+ }
+}
+EXPORT_SYMBOL(input_inject_event);
+
+/**
+ * input_alloc_absinfo - allocates array of input_absinfo structs
+ * @dev: the input device emitting absolute events
+ *
+ * If the absinfo struct the caller asked for is already allocated, this
+ * functions will not do anything.
+ */
+void input_alloc_absinfo(struct input_dev *dev)
+{
+ if (!dev->absinfo)
+ dev->absinfo = kcalloc(ABS_CNT, sizeof(struct input_absinfo),
+ GFP_KERNEL);
+
+ WARN(!dev->absinfo, "%s(): kcalloc() failed?\n", __func__);
+}
+EXPORT_SYMBOL(input_alloc_absinfo);
+
+void input_set_abs_params(struct input_dev *dev, unsigned int axis,
+ int min, int max, int fuzz, int flat)
+{
+ struct input_absinfo *absinfo;
+
+ input_alloc_absinfo(dev);
+ if (!dev->absinfo)
+ return;
+
+ absinfo = &dev->absinfo[axis];
+ absinfo->minimum = min;
+ absinfo->maximum = max;
+ absinfo->fuzz = fuzz;
+ absinfo->flat = flat;
+
+ __set_bit(EV_ABS, dev->evbit);
+ __set_bit(axis, dev->absbit);
+}
+EXPORT_SYMBOL(input_set_abs_params);
+
+
+/**
+ * input_grab_device - grabs device for exclusive use
+ * @handle: input handle that wants to own the device
+ *
+ * When a device is grabbed by an input handle all events generated by
+ * the device are delivered only to this handle. Also events injected
+ * by other input handles are ignored while device is grabbed.
+ */
+int input_grab_device(struct input_handle *handle)
+{
+ struct input_dev *dev = handle->dev;
+ int retval;
+
+ retval = mutex_lock_interruptible(&dev->mutex);
+ if (retval)
+ return retval;
+
+ if (dev->grab) {
+ retval = -EBUSY;
+ goto out;
+ }
+
+ rcu_assign_pointer(dev->grab, handle);
+
+ out:
+ mutex_unlock(&dev->mutex);
+ return retval;
+}
+EXPORT_SYMBOL(input_grab_device);
+
+static void __input_release_device(struct input_handle *handle)
+{
+ struct input_dev *dev = handle->dev;
+ struct input_handle *grabber;
+
+ grabber = rcu_dereference_protected(dev->grab,
+ lockdep_is_held(&dev->mutex));
+ if (grabber == handle) {
+ rcu_assign_pointer(dev->grab, NULL);
+ /* Make sure input_pass_event() notices that grab is gone */
+ synchronize_rcu();
+
+ list_for_each_entry(handle, &dev->h_list, d_node)
+ if (handle->open && handle->handler->start)
+ handle->handler->start(handle);
+ }
+}
+
+/**
+ * input_release_device - release previously grabbed device
+ * @handle: input handle that owns the device
+ *
+ * Releases previously grabbed device so that other input handles can
+ * start receiving input events. Upon release all handlers attached
+ * to the device have their start() method called so they have a change
+ * to synchronize device state with the rest of the system.
+ */
+void input_release_device(struct input_handle *handle)
+{
+ struct input_dev *dev = handle->dev;
+
+ mutex_lock(&dev->mutex);
+ __input_release_device(handle);
+ mutex_unlock(&dev->mutex);
+}
+EXPORT_SYMBOL(input_release_device);
+
+/**
+ * input_open_device - open input device
+ * @handle: handle through which device is being accessed
+ *
+ * This function should be called by input handlers when they
+ * want to start receive events from given input device.
+ */
+int input_open_device(struct input_handle *handle)
+{
+ struct input_dev *dev = handle->dev;
+ int retval;
+
+ retval = mutex_lock_interruptible(&dev->mutex);
+ if (retval)
+ return retval;
+
+ if (dev->going_away) {
+ retval = -ENODEV;
+ goto out;
+ }
+
+ handle->open++;
+
+ if (!dev->users++ && dev->open)
+ retval = dev->open(dev);
+
+ if (retval) {
+ dev->users--;
+ if (!--handle->open) {
+ /*
+ * Make sure we are not delivering any more events
+ * through this handle
+ */
+ synchronize_rcu();
+ }
+ }
+
+ out:
+ mutex_unlock(&dev->mutex);
+ return retval;
+}
+EXPORT_SYMBOL(input_open_device);
+
+int input_flush_device(struct input_handle *handle, struct file *file)
+{
+ struct input_dev *dev = handle->dev;
+ int retval;
+
+ retval = mutex_lock_interruptible(&dev->mutex);
+ if (retval)
+ return retval;
+
+ if (dev->flush)
+ retval = dev->flush(dev, file);
+
+ mutex_unlock(&dev->mutex);
+ return retval;
+}
+EXPORT_SYMBOL(input_flush_device);
+
+/**
+ * input_close_device - close input device
+ * @handle: handle through which device is being accessed
+ *
+ * This function should be called by input handlers when they
+ * want to stop receive events from given input device.
+ */
+void input_close_device(struct input_handle *handle)
+{
+ struct input_dev *dev = handle->dev;
+
+ mutex_lock(&dev->mutex);
+
+ __input_release_device(handle);
+
+ if (!--dev->users && dev->close)
+ dev->close(dev);
+
+ if (!--handle->open) {
+ /*
+ * synchronize_rcu() makes sure that input_pass_event()
+ * completed and that no more input events are delivered
+ * through this handle
+ */
+ synchronize_rcu();
+ }
+
+ mutex_unlock(&dev->mutex);
+}
+EXPORT_SYMBOL(input_close_device);
+
+/*
+ * Simulate keyup events for all keys that are marked as pressed.
+ * The function must be called with dev->event_lock held.
+ */
+static void input_dev_release_keys(struct input_dev *dev)
+{
+ bool need_sync = false;
+ int code;
+
+ if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) {
+ for_each_set_bit(code, dev->key, KEY_CNT) {
+ input_pass_event(dev, EV_KEY, code, 0);
+ need_sync = true;
+ }
+
+ if (need_sync)
+ input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
+
+ memset(dev->key, 0, sizeof(dev->key));
+ }
+}
+
+/*
+ * Prepare device for unregistering
+ */
+static void input_disconnect_device(struct input_dev *dev)
+{
+ struct input_handle *handle;
+
+ /*
+ * Mark device as going away. Note that we take dev->mutex here
+ * not to protect access to dev->going_away but rather to ensure
+ * that there are no threads in the middle of input_open_device()
+ */
+ mutex_lock(&dev->mutex);
+ dev->going_away = true;
+ mutex_unlock(&dev->mutex);
+
+ spin_lock_irq(&dev->event_lock);
+
+ /*
+ * Simulate keyup events for all pressed keys so that handlers
+ * are not left with "stuck" keys. The driver may continue
+ * generate events even after we done here but they will not
+ * reach any handlers.
+ */
+ input_dev_release_keys(dev);
+
+ list_for_each_entry(handle, &dev->h_list, d_node)
+ handle->open = 0;
+
+ spin_unlock_irq(&dev->event_lock);
+}
+
+/**
+ * input_scancode_to_scalar() - converts scancode in &struct input_keymap_entry
+ * @ke: keymap entry containing scancode to be converted.
+ * @scancode: pointer to the location where converted scancode should
+ * be stored.
+ *
+ * This function is used to convert scancode stored in &struct keymap_entry
+ * into scalar form understood by legacy keymap handling methods. These
+ * methods expect scancodes to be represented as 'unsigned int'.
+ */
+int input_scancode_to_scalar(const struct input_keymap_entry *ke,
+ unsigned int *scancode)
+{
+ switch (ke->len) {
+ case 1:
+ *scancode = *((u8 *)ke->scancode);
+ break;
+
+ case 2:
+ *scancode = *((u16 *)ke->scancode);
+ break;
+
+ case 4:
+ *scancode = *((u32 *)ke->scancode);
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(input_scancode_to_scalar);
+
+/*
+ * Those routines handle the default case where no [gs]etkeycode() is
+ * defined. In this case, an array indexed by the scancode is used.
+ */
+
+static unsigned int input_fetch_keycode(struct input_dev *dev,
+ unsigned int index)
+{
+ switch (dev->keycodesize) {
+ case 1:
+ return ((u8 *)dev->keycode)[index];
+
+ case 2:
+ return ((u16 *)dev->keycode)[index];
+
+ default:
+ return ((u32 *)dev->keycode)[index];
+ }
+}
+
+static int input_default_getkeycode(struct input_dev *dev,
+ struct input_keymap_entry *ke)
+{
+ unsigned int index;
+ int error;
+
+ if (!dev->keycodesize)
+ return -EINVAL;
+
+ if (ke->flags & INPUT_KEYMAP_BY_INDEX)
+ index = ke->index;
+ else {
+ error = input_scancode_to_scalar(ke, &index);
+ if (error)
+ return error;
+ }
+
+ if (index >= dev->keycodemax)
+ return -EINVAL;
+
+ ke->keycode = input_fetch_keycode(dev, index);
+ ke->index = index;
+ ke->len = sizeof(index);
+ memcpy(ke->scancode, &index, sizeof(index));
+
+ return 0;
+}
+
+static int input_default_setkeycode(struct input_dev *dev,
+ const struct input_keymap_entry *ke,
+ unsigned int *old_keycode)
+{
+ unsigned int index;
+ int error;
+ int i;
+
+ if (!dev->keycodesize)
+ return -EINVAL;
+
+ if (ke->flags & INPUT_KEYMAP_BY_INDEX) {
+ index = ke->index;
+ } else {
+ error = input_scancode_to_scalar(ke, &index);
+ if (error)
+ return error;
+ }
+
+ if (index >= dev->keycodemax)
+ return -EINVAL;
+
+ if (dev->keycodesize < sizeof(ke->keycode) &&
+ (ke->keycode >> (dev->keycodesize * 8)))
+ return -EINVAL;
+
+ switch (dev->keycodesize) {
+ case 1: {
+ u8 *k = (u8 *)dev->keycode;
+ *old_keycode = k[index];
+ k[index] = ke->keycode;
+ break;
+ }
+ case 2: {
+ u16 *k = (u16 *)dev->keycode;
+ *old_keycode = k[index];
+ k[index] = ke->keycode;
+ break;
+ }
+ default: {
+ u32 *k = (u32 *)dev->keycode;
+ *old_keycode = k[index];
+ k[index] = ke->keycode;
+ break;
+ }
+ }
+
+ __clear_bit(*old_keycode, dev->keybit);
+ __set_bit(ke->keycode, dev->keybit);
+
+ for (i = 0; i < dev->keycodemax; i++) {
+ if (input_fetch_keycode(dev, i) == *old_keycode) {
+ __set_bit(*old_keycode, dev->keybit);
+ break; /* Setting the bit twice is useless, so break */
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * input_get_keycode - retrieve keycode currently mapped to a given scancode
+ * @dev: input device which keymap is being queried
+ * @ke: keymap entry
+ *
+ * This function should be called by anyone interested in retrieving current
+ * keymap. Presently evdev handlers use it.
+ */
+int input_get_keycode(struct input_dev *dev, struct input_keymap_entry *ke)
+{
+ unsigned long flags;
+ int retval;
+
+ spin_lock_irqsave(&dev->event_lock, flags);
+ retval = dev->getkeycode(dev, ke);
+ spin_unlock_irqrestore(&dev->event_lock, flags);
+
+ return retval;
+}
+EXPORT_SYMBOL(input_get_keycode);
+
+/**
+ * input_set_keycode - attribute a keycode to a given scancode
+ * @dev: input device which keymap is being updated
+ * @ke: new keymap entry
+ *
+ * This function should be called by anyone needing to update current
+ * keymap. Presently keyboard and evdev handlers use it.
+ */
+int input_set_keycode(struct input_dev *dev,
+ const struct input_keymap_entry *ke)
+{
+ unsigned long flags;
+ unsigned int old_keycode;
+ int retval;
+
+ if (ke->keycode > KEY_MAX)
+ return -EINVAL;
+
+ spin_lock_irqsave(&dev->event_lock, flags);
+
+ retval = dev->setkeycode(dev, ke, &old_keycode);
+ if (retval)
+ goto out;
+
+ /* Make sure KEY_RESERVED did not get enabled. */
+ __clear_bit(KEY_RESERVED, dev->keybit);
+
+ /*
+ * Simulate keyup event if keycode is not present
+ * in the keymap anymore
+ */
+ if (test_bit(EV_KEY, dev->evbit) &&
+ !is_event_supported(old_keycode, dev->keybit, KEY_MAX) &&
+ __test_and_clear_bit(old_keycode, dev->key)) {
+ struct input_value vals[] = {
+ { EV_KEY, old_keycode, 0 },
+ input_value_sync
+ };
+
+ input_pass_values(dev, vals, ARRAY_SIZE(vals));
+ }
+
+ out:
+ spin_unlock_irqrestore(&dev->event_lock, flags);
+
+ return retval;
+}
+EXPORT_SYMBOL(input_set_keycode);
+
+static const struct input_device_id *input_match_device(struct input_handler *handler,
+ struct input_dev *dev)
+{
+ const struct input_device_id *id;
+
+ for (id = handler->id_table; id->flags || id->driver_info; id++) {
+
+ if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
+ if (id->bustype != dev->id.bustype)
+ continue;
+
+ if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
+ if (id->vendor != dev->id.vendor)
+ continue;
+
+ if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
+ if (id->product != dev->id.product)
+ continue;
+
+ if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
+ if (id->version != dev->id.version)
+ continue;
+
+ if (!bitmap_subset(id->evbit, dev->evbit, EV_MAX))
+ continue;
+
+ if (!bitmap_subset(id->keybit, dev->keybit, KEY_MAX))
+ continue;
+
+ if (!bitmap_subset(id->relbit, dev->relbit, REL_MAX))
+ continue;
+
+ if (!bitmap_subset(id->absbit, dev->absbit, ABS_MAX))
+ continue;
+
+ if (!bitmap_subset(id->mscbit, dev->mscbit, MSC_MAX))
+ continue;
+
+ if (!bitmap_subset(id->ledbit, dev->ledbit, LED_MAX))
+ continue;
+
+ if (!bitmap_subset(id->sndbit, dev->sndbit, SND_MAX))
+ continue;
+
+ if (!bitmap_subset(id->ffbit, dev->ffbit, FF_MAX))
+ continue;
+
+ if (!bitmap_subset(id->swbit, dev->swbit, SW_MAX))
+ continue;
+
+ if (!handler->match || handler->match(handler, dev))
+ return id;
+ }
+
+ return NULL;
+}
+
+static int input_attach_handler(struct input_dev *dev, struct input_handler *handler)
+{
+ const struct input_device_id *id;
+ int error;
+
+ id = input_match_device(handler, dev);
+ if (!id)
+ return -ENODEV;
+
+ error = handler->connect(handler, dev, id);
+ if (error && error != -ENODEV)
+ pr_err("failed to attach handler %s to device %s, error: %d\n",
+ handler->name, kobject_name(&dev->dev.kobj), error);
+
+ return error;
+}
+
+#ifdef CONFIG_COMPAT
+
+static int input_bits_to_string(char *buf, int buf_size,
+ unsigned long bits, bool skip_empty)
+{
+ int len = 0;
+
+ if (INPUT_COMPAT_TEST) {
+ u32 dword = bits >> 32;
+ if (dword || !skip_empty)
+ len += snprintf(buf, buf_size, "%x ", dword);
+
+ dword = bits & 0xffffffffUL;
+ if (dword || !skip_empty || len)
+ len += snprintf(buf + len, max(buf_size - len, 0),
+ "%x", dword);
+ } else {
+ if (bits || !skip_empty)
+ len += snprintf(buf, buf_size, "%lx", bits);
+ }
+
+ return len;
+}
+
+#else /* !CONFIG_COMPAT */
+
+static int input_bits_to_string(char *buf, int buf_size,
+ unsigned long bits, bool skip_empty)
+{
+ return bits || !skip_empty ?
+ snprintf(buf, buf_size, "%lx", bits) : 0;
+}
+
+#endif
+
+#ifdef CONFIG_PROC_FS
+
+static struct proc_dir_entry *proc_bus_input_dir;
+static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
+static int input_devices_state;
+
+static inline void input_wakeup_procfs_readers(void)
+{
+ input_devices_state++;
+ wake_up(&input_devices_poll_wait);
+}
+
+static unsigned int input_proc_devices_poll(struct file *file, poll_table *wait)
+{
+ poll_wait(file, &input_devices_poll_wait, wait);
+ if (file->f_version != input_devices_state) {
+ file->f_version = input_devices_state;
+ return POLLIN | POLLRDNORM;
+ }
+
+ return 0;
+}
+
+union input_seq_state {
+ struct {
+ unsigned short pos;
+ bool mutex_acquired;
+ };
+ void *p;
+};
+
+static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ union input_seq_state *state = (union input_seq_state *)&seq->private;
+ int error;
+
+ /* We need to fit into seq->private pointer */
+ BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
+
+ error = mutex_lock_interruptible(&input_mutex);
+ if (error) {
+ state->mutex_acquired = false;
+ return ERR_PTR(error);
+ }
+
+ state->mutex_acquired = true;
+
+ return seq_list_start(&input_dev_list, *pos);
+}
+
+static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ return seq_list_next(v, &input_dev_list, pos);
+}
+
+static void input_seq_stop(struct seq_file *seq, void *v)
+{
+ union input_seq_state *state = (union input_seq_state *)&seq->private;
+
+ if (state->mutex_acquired)
+ mutex_unlock(&input_mutex);
+}
+
+static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
+ unsigned long *bitmap, int max)
+{
+ int i;
+ bool skip_empty = true;
+ char buf[18];
+
+ seq_printf(seq, "B: %s=", name);
+
+ for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
+ if (input_bits_to_string(buf, sizeof(buf),
+ bitmap[i], skip_empty)) {
+ skip_empty = false;
+ seq_printf(seq, "%s%s", buf, i > 0 ? " " : "");
+ }
+ }
+
+ /*
+ * If no output was produced print a single 0.
+ */
+ if (skip_empty)
+ seq_puts(seq, "0");
+
+ seq_putc(seq, '\n');
+}
+
+static int input_devices_seq_show(struct seq_file *seq, void *v)
+{
+ struct input_dev *dev = container_of(v, struct input_dev, node);
+ const char *path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
+ struct input_handle *handle;
+
+ seq_printf(seq, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
+ dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
+
+ seq_printf(seq, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
+ seq_printf(seq, "P: Phys=%s\n", dev->phys ? dev->phys : "");
+ seq_printf(seq, "S: Sysfs=%s\n", path ? path : "");
+ seq_printf(seq, "U: Uniq=%s\n", dev->uniq ? dev->uniq : "");
+ seq_printf(seq, "H: Handlers=");
+
+ list_for_each_entry(handle, &dev->h_list, d_node)
+ seq_printf(seq, "%s ", handle->name);
+ seq_putc(seq, '\n');
+
+ input_seq_print_bitmap(seq, "PROP", dev->propbit, INPUT_PROP_MAX);
+
+ input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX);
+ if (test_bit(EV_KEY, dev->evbit))
+ input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX);
+ if (test_bit(EV_REL, dev->evbit))
+ input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX);
+ if (test_bit(EV_ABS, dev->evbit))
+ input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX);
+ if (test_bit(EV_MSC, dev->evbit))
+ input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX);
+ if (test_bit(EV_LED, dev->evbit))
+ input_seq_print_bitmap(seq, "LED", dev->ledbit, LED_MAX);
+ if (test_bit(EV_SND, dev->evbit))
+ input_seq_print_bitmap(seq, "SND", dev->sndbit, SND_MAX);
+ if (test_bit(EV_FF, dev->evbit))
+ input_seq_print_bitmap(seq, "FF", dev->ffbit, FF_MAX);
+ if (test_bit(EV_SW, dev->evbit))
+ input_seq_print_bitmap(seq, "SW", dev->swbit, SW_MAX);
+
+ seq_putc(seq, '\n');
+
+ kfree(path);
+ return 0;
+}
+
+static const struct seq_operations input_devices_seq_ops = {
+ .start = input_devices_seq_start,
+ .next = input_devices_seq_next,
+ .stop = input_seq_stop,
+ .show = input_devices_seq_show,
+};
+
+static int input_proc_devices_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &input_devices_seq_ops);
+}
+
+static const struct file_operations input_devices_fileops = {
+ .owner = THIS_MODULE,
+ .open = input_proc_devices_open,
+ .poll = input_proc_devices_poll,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ union input_seq_state *state = (union input_seq_state *)&seq->private;
+ int error;
+
+ /* We need to fit into seq->private pointer */
+ BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
+
+ error = mutex_lock_interruptible(&input_mutex);
+ if (error) {
+ state->mutex_acquired = false;
+ return ERR_PTR(error);
+ }
+
+ state->mutex_acquired = true;
+ state->pos = *pos;
+
+ return seq_list_start(&input_handler_list, *pos);
+}
+
+static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ union input_seq_state *state = (union input_seq_state *)&seq->private;
+
+ state->pos = *pos + 1;
+ return seq_list_next(v, &input_handler_list, pos);
+}
+
+static int input_handlers_seq_show(struct seq_file *seq, void *v)
+{
+ struct input_handler *handler = container_of(v, struct input_handler, node);
+ union input_seq_state *state = (union input_seq_state *)&seq->private;
+
+ seq_printf(seq, "N: Number=%u Name=%s", state->pos, handler->name);
+ if (handler->filter)
+ seq_puts(seq, " (filter)");
+ if (handler->legacy_minors)
+ seq_printf(seq, " Minor=%d", handler->minor);
+ seq_putc(seq, '\n');
+
+ return 0;
+}
+
+static const struct seq_operations input_handlers_seq_ops = {
+ .start = input_handlers_seq_start,
+ .next = input_handlers_seq_next,
+ .stop = input_seq_stop,
+ .show = input_handlers_seq_show,
+};
+
+static int input_proc_handlers_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &input_handlers_seq_ops);
+}
+
+static const struct file_operations input_handlers_fileops = {
+ .owner = THIS_MODULE,
+ .open = input_proc_handlers_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static int __init input_proc_init(void)
+{
+ struct proc_dir_entry *entry;
+
+ proc_bus_input_dir = proc_mkdir("bus/input", NULL);
+ if (!proc_bus_input_dir)
+ return -ENOMEM;
+
+ entry = proc_create("devices", 0, proc_bus_input_dir,
+ &input_devices_fileops);
+ if (!entry)
+ goto fail1;
+
+ entry = proc_create("handlers", 0, proc_bus_input_dir,
+ &input_handlers_fileops);
+ if (!entry)
+ goto fail2;
+
+ return 0;
+
+ fail2: remove_proc_entry("devices", proc_bus_input_dir);
+ fail1: remove_proc_entry("bus/input", NULL);
+ return -ENOMEM;
+}
+
+static void input_proc_exit(void)
+{
+ remove_proc_entry("devices", proc_bus_input_dir);
+ remove_proc_entry("handlers", proc_bus_input_dir);
+ remove_proc_entry("bus/input", NULL);
+}
+
+#else /* !CONFIG_PROC_FS */
+static inline void input_wakeup_procfs_readers(void) { }
+static inline int input_proc_init(void) { return 0; }
+static inline void input_proc_exit(void) { }
+#endif
+
+#define INPUT_DEV_STRING_ATTR_SHOW(name) \
+static ssize_t input_dev_show_##name(struct device *dev, \
+ struct device_attribute *attr, \
+ char *buf) \
+{ \
+ struct input_dev *input_dev = to_input_dev(dev); \
+ \
+ return scnprintf(buf, PAGE_SIZE, "%s\n", \
+ input_dev->name ? input_dev->name : ""); \
+} \
+static DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL)
+
+INPUT_DEV_STRING_ATTR_SHOW(name);
+INPUT_DEV_STRING_ATTR_SHOW(phys);
+INPUT_DEV_STRING_ATTR_SHOW(uniq);
+
+static int input_print_modalias_bits(char *buf, int size,
+ char name, unsigned long *bm,
+ unsigned int min_bit, unsigned int max_bit)
+{
+ int len = 0, i;
+
+ len += snprintf(buf, max(size, 0), "%c", name);
+ for (i = min_bit; i < max_bit; i++)
+ if (bm[BIT_WORD(i)] & BIT_MASK(i))
+ len += snprintf(buf + len, max(size - len, 0), "%X,", i);
+ return len;
+}
+
+static int input_print_modalias(char *buf, int size, struct input_dev *id,
+ int add_cr)
+{
+ int len;
+
+ len = snprintf(buf, max(size, 0),
+ "input:b%04Xv%04Xp%04Xe%04X-",
+ id->id.bustype, id->id.vendor,
+ id->id.product, id->id.version);
+
+ len += input_print_modalias_bits(buf + len, size - len,
+ 'e', id->evbit, 0, EV_MAX);
+ len += input_print_modalias_bits(buf + len, size - len,
+ 'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX);
+ len += input_print_modalias_bits(buf + len, size - len,
+ 'r', id->relbit, 0, REL_MAX);
+ len += input_print_modalias_bits(buf + len, size - len,
+ 'a', id->absbit, 0, ABS_MAX);
+ len += input_print_modalias_bits(buf + len, size - len,
+ 'm', id->mscbit, 0, MSC_MAX);
+ len += input_print_modalias_bits(buf + len, size - len,
+ 'l', id->ledbit, 0, LED_MAX);
+ len += input_print_modalias_bits(buf + len, size - len,
+ 's', id->sndbit, 0, SND_MAX);
+ len += input_print_modalias_bits(buf + len, size - len,
+ 'f', id->ffbit, 0, FF_MAX);
+ len += input_print_modalias_bits(buf + len, size - len,
+ 'w', id->swbit, 0, SW_MAX);
+
+ if (add_cr)
+ len += snprintf(buf + len, max(size - len, 0), "\n");
+
+ return len;
+}
+
+static ssize_t input_dev_show_modalias(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct input_dev *id = to_input_dev(dev);
+ ssize_t len;
+
+ len = input_print_modalias(buf, PAGE_SIZE, id, 1);
+
+ return min_t(int, len, PAGE_SIZE);
+}
+static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
+
+static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
+ int max, int add_cr);
+
+static ssize_t input_dev_show_properties(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct input_dev *input_dev = to_input_dev(dev);
+ int len = input_print_bitmap(buf, PAGE_SIZE, input_dev->propbit,
+ INPUT_PROP_MAX, true);
+ return min_t(int, len, PAGE_SIZE);
+}
+static DEVICE_ATTR(properties, S_IRUGO, input_dev_show_properties, NULL);
+
+static struct attribute *input_dev_attrs[] = {
+ &dev_attr_name.attr,
+ &dev_attr_phys.attr,
+ &dev_attr_uniq.attr,
+ &dev_attr_modalias.attr,
+ &dev_attr_properties.attr,
+ NULL
+};
+
+static struct attribute_group input_dev_attr_group = {
+ .attrs = input_dev_attrs,
+};
+
+#define INPUT_DEV_ID_ATTR(name) \
+static ssize_t input_dev_show_id_##name(struct device *dev, \
+ struct device_attribute *attr, \
+ char *buf) \
+{ \
+ struct input_dev *input_dev = to_input_dev(dev); \
+ return scnprintf(buf, PAGE_SIZE, "%04x\n", input_dev->id.name); \
+} \
+static DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL)
+
+INPUT_DEV_ID_ATTR(bustype);
+INPUT_DEV_ID_ATTR(vendor);
+INPUT_DEV_ID_ATTR(product);
+INPUT_DEV_ID_ATTR(version);
+
+static struct attribute *input_dev_id_attrs[] = {
+ &dev_attr_bustype.attr,
+ &dev_attr_vendor.attr,
+ &dev_attr_product.attr,
+ &dev_attr_version.attr,
+ NULL
+};
+
+static struct attribute_group input_dev_id_attr_group = {
+ .name = "id",
+ .attrs = input_dev_id_attrs,
+};
+
+static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
+ int max, int add_cr)
+{
+ int i;
+ int len = 0;
+ bool skip_empty = true;
+
+ for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
+ len += input_bits_to_string(buf + len, max(buf_size - len, 0),
+ bitmap[i], skip_empty);
+ if (len) {
+ skip_empty = false;
+ if (i > 0)
+ len += snprintf(buf + len, max(buf_size - len, 0), " ");
+ }
+ }
+
+ /*
+ * If no output was produced print a single 0.
+ */
+ if (len == 0)
+ len = snprintf(buf, buf_size, "%d", 0);
+
+ if (add_cr)
+ len += snprintf(buf + len, max(buf_size - len, 0), "\n");
+
+ return len;
+}
+
+#define INPUT_DEV_CAP_ATTR(ev, bm) \
+static ssize_t input_dev_show_cap_##bm(struct device *dev, \
+ struct device_attribute *attr, \
+ char *buf) \
+{ \
+ struct input_dev *input_dev = to_input_dev(dev); \
+ int len = input_print_bitmap(buf, PAGE_SIZE, \
+ input_dev->bm##bit, ev##_MAX, \
+ true); \
+ return min_t(int, len, PAGE_SIZE); \
+} \
+static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL)
+
+INPUT_DEV_CAP_ATTR(EV, ev);
+INPUT_DEV_CAP_ATTR(KEY, key);
+INPUT_DEV_CAP_ATTR(REL, rel);
+INPUT_DEV_CAP_ATTR(ABS, abs);
+INPUT_DEV_CAP_ATTR(MSC, msc);
+INPUT_DEV_CAP_ATTR(LED, led);
+INPUT_DEV_CAP_ATTR(SND, snd);
+INPUT_DEV_CAP_ATTR(FF, ff);
+INPUT_DEV_CAP_ATTR(SW, sw);
+
+static struct attribute *input_dev_caps_attrs[] = {
+ &dev_attr_ev.attr,
+ &dev_attr_key.attr,
+ &dev_attr_rel.attr,
+ &dev_attr_abs.attr,
+ &dev_attr_msc.attr,
+ &dev_attr_led.attr,
+ &dev_attr_snd.attr,
+ &dev_attr_ff.attr,
+ &dev_attr_sw.attr,
+ NULL
+};
+
+static struct attribute_group input_dev_caps_attr_group = {
+ .name = "capabilities",
+ .attrs = input_dev_caps_attrs,
+};
+
+static const struct attribute_group *input_dev_attr_groups[] = {
+ &input_dev_attr_group,
+ &input_dev_id_attr_group,
+ &input_dev_caps_attr_group,
+ NULL
+};
+
+static void input_dev_release(struct device *device)
+{
+ struct input_dev *dev = to_input_dev(device);
+
+ input_ff_destroy(dev);
+ input_mt_destroy_slots(dev);
+ kfree(dev->absinfo);
+ kfree(dev->vals);
+ kfree(dev);
+
+ module_put(THIS_MODULE);
+}
+
+/*
+ * Input uevent interface - loading event handlers based on
+ * device bitfields.
+ */
+static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
+ const char *name, unsigned long *bitmap, int max)
+{
+ int len;
+
+ if (add_uevent_var(env, "%s", name))
+ return -ENOMEM;
+
+ len = input_print_bitmap(&env->buf[env->buflen - 1],
+ sizeof(env->buf) - env->buflen,
+ bitmap, max, false);
+ if (len >= (sizeof(env->buf) - env->buflen))
+ return -ENOMEM;
+
+ env->buflen += len;
+ return 0;
+}
+
+static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
+ struct input_dev *dev)
+{
+ int len;
+
+ if (add_uevent_var(env, "MODALIAS="))
+ return -ENOMEM;
+
+ len = input_print_modalias(&env->buf[env->buflen - 1],
+ sizeof(env->buf) - env->buflen,
+ dev, 0);
+ if (len >= (sizeof(env->buf) - env->buflen))
+ return -ENOMEM;
+
+ env->buflen += len;
+ return 0;
+}
+
+#define INPUT_ADD_HOTPLUG_VAR(fmt, val...) \
+ do { \
+ int err = add_uevent_var(env, fmt, val); \
+ if (err) \
+ return err; \
+ } while (0)
+
+#define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max) \
+ do { \
+ int err = input_add_uevent_bm_var(env, name, bm, max); \
+ if (err) \
+ return err; \
+ } while (0)
+
+#define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev) \
+ do { \
+ int err = input_add_uevent_modalias_var(env, dev); \
+ if (err) \
+ return err; \
+ } while (0)
+
+static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env)
+{
+ struct input_dev *dev = to_input_dev(device);
+
+ INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
+ dev->id.bustype, dev->id.vendor,
+ dev->id.product, dev->id.version);
+ if (dev->name)
+ INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name);
+ if (dev->phys)
+ INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys);
+ if (dev->uniq)
+ INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq);
+
+ INPUT_ADD_HOTPLUG_BM_VAR("PROP=", dev->propbit, INPUT_PROP_MAX);
+
+ INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX);
+ if (test_bit(EV_KEY, dev->evbit))
+ INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX);
+ if (test_bit(EV_REL, dev->evbit))
+ INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX);
+ if (test_bit(EV_ABS, dev->evbit))
+ INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX);
+ if (test_bit(EV_MSC, dev->evbit))
+ INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX);
+ if (test_bit(EV_LED, dev->evbit))
+ INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX);
+ if (test_bit(EV_SND, dev->evbit))
+ INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX);
+ if (test_bit(EV_FF, dev->evbit))
+ INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX);
+ if (test_bit(EV_SW, dev->evbit))
+ INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX);
+
+ INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev);
+
+ return 0;
+}
+
+#define INPUT_DO_TOGGLE(dev, type, bits, on) \
+ do { \
+ int i; \
+ bool active; \
+ \
+ if (!test_bit(EV_##type, dev->evbit)) \
+ break; \
+ \
+ for_each_set_bit(i, dev->bits##bit, type##_CNT) { \
+ active = test_bit(i, dev->bits); \
+ if (!active && !on) \
+ continue; \
+ \
+ dev->event(dev, EV_##type, i, on ? active : 0); \
+ } \
+ } while (0)
+
+static void input_dev_toggle(struct input_dev *dev, bool activate)
+{
+ if (!dev->event)
+ return;
+
+ INPUT_DO_TOGGLE(dev, LED, led, activate);
+ INPUT_DO_TOGGLE(dev, SND, snd, activate);
+
+ if (activate && test_bit(EV_REP, dev->evbit)) {
+ dev->event(dev, EV_REP, REP_PERIOD, dev->rep[REP_PERIOD]);
+ dev->event(dev, EV_REP, REP_DELAY, dev->rep[REP_DELAY]);
+ }
+}
+
+/**
+ * input_reset_device() - reset/restore the state of input device
+ * @dev: input device whose state needs to be reset
+ *
+ * This function tries to reset the state of an opened input device and
+ * bring internal state and state if the hardware in sync with each other.
+ * We mark all keys as released, restore LED state, repeat rate, etc.
+ */
+void input_reset_device(struct input_dev *dev)
+{
+ unsigned long flags;
+
+ mutex_lock(&dev->mutex);
+ spin_lock_irqsave(&dev->event_lock, flags);
+
+ input_dev_toggle(dev, true);
+ input_dev_release_keys(dev);
+
+ spin_unlock_irqrestore(&dev->event_lock, flags);
+ mutex_unlock(&dev->mutex);
+}
+EXPORT_SYMBOL(input_reset_device);
+
+#ifdef CONFIG_PM_SLEEP
+static int input_dev_suspend(struct device *dev)
+{
+ struct input_dev *input_dev = to_input_dev(dev);
+
+ spin_lock_irq(&input_dev->event_lock);
+
+ /*
+ * Keys that are pressed now are unlikely to be
+ * still pressed when we resume.
+ */
+ input_dev_release_keys(input_dev);
+
+ /* Turn off LEDs and sounds, if any are active. */
+ input_dev_toggle(input_dev, false);
+
+ spin_unlock_irq(&input_dev->event_lock);
+
+ return 0;
+}
+
+static int input_dev_resume(struct device *dev)
+{
+ struct input_dev *input_dev = to_input_dev(dev);
+
+ spin_lock_irq(&input_dev->event_lock);
+
+ /* Restore state of LEDs and sounds, if any were active. */
+ input_dev_toggle(input_dev, true);
+
+ spin_unlock_irq(&input_dev->event_lock);
+
+ return 0;
+}
+
+static int input_dev_freeze(struct device *dev)
+{
+ struct input_dev *input_dev = to_input_dev(dev);
+
+ spin_lock_irq(&input_dev->event_lock);
+
+ /*
+ * Keys that are pressed now are unlikely to be
+ * still pressed when we resume.
+ */
+ input_dev_release_keys(input_dev);
+
+ spin_unlock_irq(&input_dev->event_lock);
+
+ return 0;
+}
+
+static int input_dev_poweroff(struct device *dev)
+{
+ struct input_dev *input_dev = to_input_dev(dev);
+
+ spin_lock_irq(&input_dev->event_lock);
+
+ /* Turn off LEDs and sounds, if any are active. */
+ input_dev_toggle(input_dev, false);
+
+ spin_unlock_irq(&input_dev->event_lock);
+
+ return 0;
+}
+
+static const struct dev_pm_ops input_dev_pm_ops = {
+ .suspend = input_dev_suspend,
+ .resume = input_dev_resume,
+ .freeze = input_dev_freeze,
+ .poweroff = input_dev_poweroff,
+ .restore = input_dev_resume,
+};
+#endif /* CONFIG_PM */
+
+static struct device_type input_dev_type = {
+ .groups = input_dev_attr_groups,
+ .release = input_dev_release,
+ .uevent = input_dev_uevent,
+#ifdef CONFIG_PM_SLEEP
+ .pm = &input_dev_pm_ops,
+#endif
+};
+
+static char *input_devnode(struct device *dev, umode_t *mode)
+{
+ return kasprintf(GFP_KERNEL, "input/%s", dev_name(dev));
+}
+
+struct class input_class = {
+ .name = "input",
+ .devnode = input_devnode,
+};
+EXPORT_SYMBOL_GPL(input_class);
+
+/**
+ * input_allocate_device - allocate memory for new input device
+ *
+ * Returns prepared struct input_dev or %NULL.
+ *
+ * NOTE: Use input_free_device() to free devices that have not been
+ * registered; input_unregister_device() should be used for already
+ * registered devices.
+ */
+struct input_dev *input_allocate_device(void)
+{
+ static atomic_t input_no = ATOMIC_INIT(-1);
+ struct input_dev *dev;
+
+ dev = kzalloc(sizeof(struct input_dev), GFP_KERNEL);
+ if (dev) {
+ dev->dev.type = &input_dev_type;
+ dev->dev.class = &input_class;
+ device_initialize(&dev->dev);
+ mutex_init(&dev->mutex);
+ spin_lock_init(&dev->event_lock);
+ init_timer(&dev->timer);
+ INIT_LIST_HEAD(&dev->h_list);
+ INIT_LIST_HEAD(&dev->node);
+
+ dev_set_name(&dev->dev, "input%lu",
+ (unsigned long)atomic_inc_return(&input_no));
+
+ __module_get(THIS_MODULE);
+ }
+
+ return dev;
+}
+EXPORT_SYMBOL(input_allocate_device);
+
+struct input_devres {
+ struct input_dev *input;
+};
+
+static int devm_input_device_match(struct device *dev, void *res, void *data)
+{
+ struct input_devres *devres = res;
+
+ return devres->input == data;
+}
+
+static void devm_input_device_release(struct device *dev, void *res)
+{
+ struct input_devres *devres = res;
+ struct input_dev *input = devres->input;
+
+ dev_dbg(dev, "%s: dropping reference to %s\n",
+ __func__, dev_name(&input->dev));
+ input_put_device(input);
+}
+
+/**
+ * devm_input_allocate_device - allocate managed input device
+ * @dev: device owning the input device being created
+ *
+ * Returns prepared struct input_dev or %NULL.
+ *
+ * Managed input devices do not need to be explicitly unregistered or
+ * freed as it will be done automatically when owner device unbinds from
+ * its driver (or binding fails). Once managed input device is allocated,
+ * it is ready to be set up and registered in the same fashion as regular
+ * input device. There are no special devm_input_device_[un]register()
+ * variants, regular ones work with both managed and unmanaged devices,
+ * should you need them. In most cases however, managed input device need
+ * not be explicitly unregistered or freed.
+ *
+ * NOTE: the owner device is set up as parent of input device and users
+ * should not override it.
+ */
+struct input_dev *devm_input_allocate_device(struct device *dev)
+{
+ struct input_dev *input;
+ struct input_devres *devres;
+
+ devres = devres_alloc(devm_input_device_release,
+ sizeof(struct input_devres), GFP_KERNEL);
+ if (!devres)
+ return NULL;
+
+ input = input_allocate_device();
+ if (!input) {
+ devres_free(devres);
+ return NULL;
+ }
+
+ input->dev.parent = dev;
+ input->devres_managed = true;
+
+ devres->input = input;
+ devres_add(dev, devres);
+
+ return input;
+}
+EXPORT_SYMBOL(devm_input_allocate_device);
+
+/**
+ * input_free_device - free memory occupied by input_dev structure
+ * @dev: input device to free
+ *
+ * This function should only be used if input_register_device()
+ * was not called yet or if it failed. Once device was registered
+ * use input_unregister_device() and memory will be freed once last
+ * reference to the device is dropped.
+ *
+ * Device should be allocated by input_allocate_device().
+ *
+ * NOTE: If there are references to the input device then memory
+ * will not be freed until last reference is dropped.
+ */
+void input_free_device(struct input_dev *dev)
+{
+ if (dev) {
+ if (dev->devres_managed)
+ WARN_ON(devres_destroy(dev->dev.parent,
+ devm_input_device_release,
+ devm_input_device_match,
+ dev));
+ input_put_device(dev);
+ }
+}
+EXPORT_SYMBOL(input_free_device);
+
+/**
+ * input_set_capability - mark device as capable of a certain event
+ * @dev: device that is capable of emitting or accepting event
+ * @type: type of the event (EV_KEY, EV_REL, etc...)
+ * @code: event code
+ *
+ * In addition to setting up corresponding bit in appropriate capability
+ * bitmap the function also adjusts dev->evbit.
+ */
+void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
+{
+ switch (type) {
+ case EV_KEY:
+ __set_bit(code, dev->keybit);
+ break;
+
+ case EV_REL:
+ __set_bit(code, dev->relbit);
+ break;
+
+ case EV_ABS:
+ input_alloc_absinfo(dev);
+ if (!dev->absinfo)
+ return;
+
+ __set_bit(code, dev->absbit);
+ break;
+
+ case EV_MSC:
+ __set_bit(code, dev->mscbit);
+ break;
+
+ case EV_SW:
+ __set_bit(code, dev->swbit);
+ break;
+
+ case EV_LED:
+ __set_bit(code, dev->ledbit);
+ break;
+
+ case EV_SND:
+ __set_bit(code, dev->sndbit);
+ break;
+
+ case EV_FF:
+ __set_bit(code, dev->ffbit);
+ break;
+
+ case EV_PWR:
+ /* do nothing */
+ break;
+
+ default:
+ pr_err("input_set_capability: unknown type %u (code %u)\n",
+ type, code);
+ dump_stack();
+ return;
+ }
+
+ __set_bit(type, dev->evbit);
+}
+EXPORT_SYMBOL(input_set_capability);
+
+static unsigned int input_estimate_events_per_packet(struct input_dev *dev)
+{
+ int mt_slots;
+ int i;
+ unsigned int events;
+
+ if (dev->mt) {
+ mt_slots = dev->mt->num_slots;
+ } else if (test_bit(ABS_MT_TRACKING_ID, dev->absbit)) {
+ mt_slots = dev->absinfo[ABS_MT_TRACKING_ID].maximum -
+ dev->absinfo[ABS_MT_TRACKING_ID].minimum + 1,
+ mt_slots = clamp(mt_slots, 2, 32);
+ } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
+ mt_slots = 2;
+ } else {
+ mt_slots = 0;
+ }
+
+ events = mt_slots + 1; /* count SYN_MT_REPORT and SYN_REPORT */
+
+ if (test_bit(EV_ABS, dev->evbit))
+ for_each_set_bit(i, dev->absbit, ABS_CNT)
+ events += input_is_mt_axis(i) ? mt_slots : 1;
+
+ if (test_bit(EV_REL, dev->evbit))
+ events += bitmap_weight(dev->relbit, REL_CNT);
+
+ /* Make room for KEY and MSC events */
+ events += 7;
+
+ return events;
+}
+
+#define INPUT_CLEANSE_BITMASK(dev, type, bits) \
+ do { \
+ if (!test_bit(EV_##type, dev->evbit)) \
+ memset(dev->bits##bit, 0, \
+ sizeof(dev->bits##bit)); \
+ } while (0)
+
+static void input_cleanse_bitmasks(struct input_dev *dev)
+{
+ INPUT_CLEANSE_BITMASK(dev, KEY, key);
+ INPUT_CLEANSE_BITMASK(dev, REL, rel);
+ INPUT_CLEANSE_BITMASK(dev, ABS, abs);
+ INPUT_CLEANSE_BITMASK(dev, MSC, msc);
+ INPUT_CLEANSE_BITMASK(dev, LED, led);
+ INPUT_CLEANSE_BITMASK(dev, SND, snd);
+ INPUT_CLEANSE_BITMASK(dev, FF, ff);
+ INPUT_CLEANSE_BITMASK(dev, SW, sw);
+}
+
+static void __input_unregister_device(struct input_dev *dev)
+{
+ struct input_handle *handle, *next;
+
+ input_disconnect_device(dev);
+
+ mutex_lock(&input_mutex);
+
+ list_for_each_entry_safe(handle, next, &dev->h_list, d_node)
+ handle->handler->disconnect(handle);
+ WARN_ON(!list_empty(&dev->h_list));
+
+ del_timer_sync(&dev->timer);
+ list_del_init(&dev->node);
+
+ input_wakeup_procfs_readers();
+
+ mutex_unlock(&input_mutex);
+
+ device_del(&dev->dev);
+}
+
+static void devm_input_device_unregister(struct device *dev, void *res)
+{
+ struct input_devres *devres = res;
+ struct input_dev *input = devres->input;
+
+ dev_dbg(dev, "%s: unregistering device %s\n",
+ __func__, dev_name(&input->dev));
+ __input_unregister_device(input);
+}
+
+/**
+ * input_enable_softrepeat - enable software autorepeat
+ * @dev: input device
+ * @delay: repeat delay
+ * @period: repeat period
+ *
+ * Enable software autorepeat on the input device.
+ */
+void input_enable_softrepeat(struct input_dev *dev, int delay, int period)
+{
+ dev->timer.data = (unsigned long) dev;
+ dev->timer.function = input_repeat_key;
+ dev->rep[REP_DELAY] = delay;
+ dev->rep[REP_PERIOD] = period;
+}
+EXPORT_SYMBOL(input_enable_softrepeat);
+
+/**
+ * input_register_device - register device with input core
+ * @dev: device to be registered
+ *
+ * This function registers device with input core. The device must be
+ * allocated with input_allocate_device() and all it's capabilities
+ * set up before registering.
+ * If function fails the device must be freed with input_free_device().
+ * Once device has been successfully registered it can be unregistered
+ * with input_unregister_device(); input_free_device() should not be
+ * called in this case.
+ *
+ * Note that this function is also used to register managed input devices
+ * (ones allocated with devm_input_allocate_device()). Such managed input
+ * devices need not be explicitly unregistered or freed, their tear down
+ * is controlled by the devres infrastructure. It is also worth noting
+ * that tear down of managed input devices is internally a 2-step process:
+ * registered managed input device is first unregistered, but stays in
+ * memory and can still handle input_event() calls (although events will
+ * not be delivered anywhere). The freeing of managed input device will
+ * happen later, when devres stack is unwound to the point where device
+ * allocation was made.
+ */
+int input_register_device(struct input_dev *dev)
+{
+ struct input_devres *devres = NULL;
+ struct input_handler *handler;
+ unsigned int packet_size;
+ const char *path;
+ int error;
+
+ if (dev->devres_managed) {
+ devres = devres_alloc(devm_input_device_unregister,
+ sizeof(struct input_devres), GFP_KERNEL);
+ if (!devres)
+ return -ENOMEM;
+
+ devres->input = dev;
+ }
+
+ /* Every input device generates EV_SYN/SYN_REPORT events. */
+ __set_bit(EV_SYN, dev->evbit);
+
+ /* KEY_RESERVED is not supposed to be transmitted to userspace. */
+ __clear_bit(KEY_RESERVED, dev->keybit);
+
+ /* Make sure that bitmasks not mentioned in dev->evbit are clean. */
+ input_cleanse_bitmasks(dev);
+
+ packet_size = input_estimate_events_per_packet(dev);
+ if (dev->hint_events_per_packet < packet_size)
+ dev->hint_events_per_packet = packet_size;
+
+ dev->max_vals = dev->hint_events_per_packet + 2;
+ dev->vals = kcalloc(dev->max_vals, sizeof(*dev->vals), GFP_KERNEL);
+ if (!dev->vals) {
+ error = -ENOMEM;
+ goto err_devres_free;
+ }
+
+ /*
+ * If delay and period are pre-set by the driver, then autorepeating
+ * is handled by the driver itself and we don't do it in input.c.
+ */
+ if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD])
+ input_enable_softrepeat(dev, 250, 33);
+
+ if (!dev->getkeycode)
+ dev->getkeycode = input_default_getkeycode;
+
+ if (!dev->setkeycode)
+ dev->setkeycode = input_default_setkeycode;
+
+ error = device_add(&dev->dev);
+ if (error)
+ goto err_free_vals;
+
+ path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL);
+ pr_info("%s as %s\n",
+ dev->name ? dev->name : "Unspecified device",
+ path ? path : "N/A");
+ kfree(path);
+
+ error = mutex_lock_interruptible(&input_mutex);
+ if (error)
+ goto err_device_del;
+
+ list_add_tail(&dev->node, &input_dev_list);
+
+ list_for_each_entry(handler, &input_handler_list, node)
+ input_attach_handler(dev, handler);
+
+ input_wakeup_procfs_readers();
+
+ mutex_unlock(&input_mutex);
+
+ if (dev->devres_managed) {
+ dev_dbg(dev->dev.parent, "%s: registering %s with devres.\n",
+ __func__, dev_name(&dev->dev));
+ devres_add(dev->dev.parent, devres);
+ }
+ return 0;
+
+err_device_del:
+ device_del(&dev->dev);
+err_free_vals:
+ kfree(dev->vals);
+ dev->vals = NULL;
+err_devres_free:
+ devres_free(devres);
+ return error;
+}
+EXPORT_SYMBOL(input_register_device);
+
+/**
+ * input_unregister_device - unregister previously registered device
+ * @dev: device to be unregistered
+ *
+ * This function unregisters an input device. Once device is unregistered
+ * the caller should not try to access it as it may get freed at any moment.
+ */
+void input_unregister_device(struct input_dev *dev)
+{
+ if (dev->devres_managed) {
+ WARN_ON(devres_destroy(dev->dev.parent,
+ devm_input_device_unregister,
+ devm_input_device_match,
+ dev));
+ __input_unregister_device(dev);
+ /*
+ * We do not do input_put_device() here because it will be done
+ * when 2nd devres fires up.
+ */
+ } else {
+ __input_unregister_device(dev);
+ input_put_device(dev);
+ }
+}
+EXPORT_SYMBOL(input_unregister_device);
+
+/**
+ * input_register_handler - register a new input handler
+ * @handler: handler to be registered
+ *
+ * This function registers a new input handler (interface) for input
+ * devices in the system and attaches it to all input devices that
+ * are compatible with the handler.
+ */
+int input_register_handler(struct input_handler *handler)
+{
+ struct input_dev *dev;
+ int error;
+
+ error = mutex_lock_interruptible(&input_mutex);
+ if (error)
+ return error;
+
+ INIT_LIST_HEAD(&handler->h_list);
+
+ list_add_tail(&handler->node, &input_handler_list);
+
+ list_for_each_entry(dev, &input_dev_list, node)
+ input_attach_handler(dev, handler);
+
+ input_wakeup_procfs_readers();
+
+ mutex_unlock(&input_mutex);
+ return 0;
+}
+EXPORT_SYMBOL(input_register_handler);
+
+/**
+ * input_unregister_handler - unregisters an input handler
+ * @handler: handler to be unregistered
+ *
+ * This function disconnects a handler from its input devices and
+ * removes it from lists of known handlers.
+ */
+void input_unregister_handler(struct input_handler *handler)
+{
+ struct input_handle *handle, *next;
+
+ mutex_lock(&input_mutex);
+
+ list_for_each_entry_safe(handle, next, &handler->h_list, h_node)
+ handler->disconnect(handle);
+ WARN_ON(!list_empty(&handler->h_list));
+
+ list_del_init(&handler->node);
+
+ input_wakeup_procfs_readers();
+
+ mutex_unlock(&input_mutex);
+}
+EXPORT_SYMBOL(input_unregister_handler);
+
+/**
+ * input_handler_for_each_handle - handle iterator
+ * @handler: input handler to iterate
+ * @data: data for the callback
+ * @fn: function to be called for each handle
+ *
+ * Iterate over @bus's list of devices, and call @fn for each, passing
+ * it @data and stop when @fn returns a non-zero value. The function is
+ * using RCU to traverse the list and therefore may be using in atomic
+ * contexts. The @fn callback is invoked from RCU critical section and
+ * thus must not sleep.
+ */
+int input_handler_for_each_handle(struct input_handler *handler, void *data,
+ int (*fn)(struct input_handle *, void *))
+{
+ struct input_handle *handle;
+ int retval = 0;
+
+ rcu_read_lock();
+
+ list_for_each_entry_rcu(handle, &handler->h_list, h_node) {
+ retval = fn(handle, data);
+ if (retval)
+ break;
+ }
+
+ rcu_read_unlock();
+
+ return retval;
+}
+EXPORT_SYMBOL(input_handler_for_each_handle);
+
+/**
+ * input_register_handle - register a new input handle
+ * @handle: handle to register
+ *
+ * This function puts a new input handle onto device's
+ * and handler's lists so that events can flow through
+ * it once it is opened using input_open_device().
+ *
+ * This function is supposed to be called from handler's
+ * connect() method.
+ */
+int input_register_handle(struct input_handle *handle)
+{
+ struct input_handler *handler = handle->handler;
+ struct input_dev *dev = handle->dev;
+ int error;
+
+ /*
+ * We take dev->mutex here to prevent race with
+ * input_release_device().
+ */
+ error = mutex_lock_interruptible(&dev->mutex);
+ if (error)
+ return error;
+
+ /*
+ * Filters go to the head of the list, normal handlers
+ * to the tail.
+ */
+ if (handler->filter)
+ list_add_rcu(&handle->d_node, &dev->h_list);
+ else
+ list_add_tail_rcu(&handle->d_node, &dev->h_list);
+
+ mutex_unlock(&dev->mutex);
+
+ /*
+ * Since we are supposed to be called from ->connect()
+ * which is mutually exclusive with ->disconnect()
+ * we can't be racing with input_unregister_handle()
+ * and so separate lock is not needed here.
+ */
+ list_add_tail_rcu(&handle->h_node, &handler->h_list);
+
+ if (handler->start)
+ handler->start(handle);
+
+ return 0;
+}
+EXPORT_SYMBOL(input_register_handle);
+
+/**
+ * input_unregister_handle - unregister an input handle
+ * @handle: handle to unregister
+ *
+ * This function removes input handle from device's
+ * and handler's lists.
+ *
+ * This function is supposed to be called from handler's
+ * disconnect() method.
+ */
+void input_unregister_handle(struct input_handle *handle)
+{
+ struct input_dev *dev = handle->dev;
+
+ list_del_rcu(&handle->h_node);
+
+ /*
+ * Take dev->mutex to prevent race with input_release_device().
+ */
+ mutex_lock(&dev->mutex);
+ list_del_rcu(&handle->d_node);
+ mutex_unlock(&dev->mutex);
+
+ synchronize_rcu();
+}
+EXPORT_SYMBOL(input_unregister_handle);
+
+/**
+ * input_get_new_minor - allocates a new input minor number
+ * @legacy_base: beginning or the legacy range to be searched
+ * @legacy_num: size of legacy range
+ * @allow_dynamic: whether we can also take ID from the dynamic range
+ *
+ * This function allocates a new device minor for from input major namespace.
+ * Caller can request legacy minor by specifying @legacy_base and @legacy_num
+ * parameters and whether ID can be allocated from dynamic range if there are
+ * no free IDs in legacy range.
+ */
+int input_get_new_minor(int legacy_base, unsigned int legacy_num,
+ bool allow_dynamic)
+{
+ /*
+ * This function should be called from input handler's ->connect()
+ * methods, which are serialized with input_mutex, so no additional
+ * locking is needed here.
+ */
+ if (legacy_base >= 0) {
+ int minor = ida_simple_get(&input_ida,
+ legacy_base,
+ legacy_base + legacy_num,
+ GFP_KERNEL);
+ if (minor >= 0 || !allow_dynamic)
+ return minor;
+ }
+
+ return ida_simple_get(&input_ida,
+ INPUT_FIRST_DYNAMIC_DEV, INPUT_MAX_CHAR_DEVICES,
+ GFP_KERNEL);
+}
+EXPORT_SYMBOL(input_get_new_minor);
+
+/**
+ * input_free_minor - release previously allocated minor
+ * @minor: minor to be released
+ *
+ * This function releases previously allocated input minor so that it can be
+ * reused later.
+ */
+void input_free_minor(unsigned int minor)
+{
+ ida_simple_remove(&input_ida, minor);
+}
+EXPORT_SYMBOL(input_free_minor);
+
+static int __init input_init(void)
+{
+ int err;
+
+ err = class_register(&input_class);
+ if (err) {
+ pr_err("unable to register input_dev class\n");
+ return err;
+ }
+
+ err = input_proc_init();
+ if (err)
+ goto fail1;
+
+ err = register_chrdev_region(MKDEV(INPUT_MAJOR, 0),
+ INPUT_MAX_CHAR_DEVICES, "input");
+ if (err) {
+ pr_err("unable to register char major %d", INPUT_MAJOR);
+ goto fail2;
+ }
+
+ return 0;
+
+ fail2: input_proc_exit();
+ fail1: class_unregister(&input_class);
+ return err;
+}
+
+static void __exit input_exit(void)
+{
+ input_proc_exit();
+ unregister_chrdev_region(MKDEV(INPUT_MAJOR, 0),
+ INPUT_MAX_CHAR_DEVICES);
+ class_unregister(&input_class);
+}
+
+subsys_initcall(input_init);
+module_exit(input_exit);