diff options
Diffstat (limited to 'drivers/input/input.c')
| -rw-r--r-- | drivers/input/input.c | 2696 |
1 files changed, 2696 insertions, 0 deletions
diff --git a/drivers/input/input.c b/drivers/input/input.c new file mode 100644 index 000000000..8b6a922f8 --- /dev/null +++ b/drivers/input/input.c @@ -0,0 +1,2696 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * The input core + * + * Copyright (c) 1999-2002 Vojtech Pavlik + */ + + +#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" +#include "input-core-private.h" +#include "input-poller.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 const unsigned int input_max_code[EV_CNT] = { + [EV_KEY] = KEY_MAX, + [EV_REL] = REL_MAX, + [EV_ABS] = ABS_MAX, + [EV_MSC] = MSC_MAX, + [EV_SW] = SW_MAX, + [EV_LED] = LED_MAX, + [EV_SND] = SND_MAX, + [EV_FF] = FF_MAX, +}; + +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.function) { + 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; + + lockdep_assert_held(&dev->event_lock); + + 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(); + + /* 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); + } + } + } +} + +#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; + + /* filter-out events from inhibited devices */ + if (dev->inhibited) + return INPUT_IGNORE_EVENT; + + 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_event_dispose(struct input_dev *dev, int disposition, + unsigned int type, unsigned int code, int 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; + /* + * Reset the timestamp on flush so we won't end up + * with a stale one. Note we only need to reset the + * monolithic one as we use its presence when deciding + * whether to generate a synthetic timestamp. + */ + dev->timestamp[INPUT_CLK_MONO] = ktime_set(0, 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; + } +} + +void input_handle_event(struct input_dev *dev, + unsigned int type, unsigned int code, int value) +{ + int disposition; + + lockdep_assert_held(&dev->event_lock); + + disposition = input_get_disposition(dev, type, code, &value); + if (disposition != INPUT_IGNORE_EVENT) { + if (type != EV_SYN) + add_input_randomness(type, code, value); + + input_event_dispose(dev, disposition, type, code, value); + } +} + +/** + * 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) + return; + + dev->absinfo = kcalloc(ABS_CNT, sizeof(*dev->absinfo), GFP_KERNEL); + if (!dev->absinfo) { + dev_err(dev->dev.parent ?: &dev->dev, + "%s: unable to allocate memory\n", __func__); + /* + * We will handle this allocation failure in + * input_register_device() when we refuse to register input + * device with ABS bits but without absinfo. + */ + } +} +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; + + __set_bit(EV_ABS, dev->evbit); + __set_bit(axis, dev->absbit); + + input_alloc_absinfo(dev); + if (!dev->absinfo) + return; + + absinfo = &dev->absinfo[axis]; + absinfo->minimum = min; + absinfo->maximum = max; + absinfo->fuzz = fuzz; + absinfo->flat = flat; +} +EXPORT_SYMBOL(input_set_abs_params); + +/** + * input_copy_abs - Copy absinfo from one input_dev to another + * @dst: Destination input device to copy the abs settings to + * @dst_axis: ABS_* value selecting the destination axis + * @src: Source input device to copy the abs settings from + * @src_axis: ABS_* value selecting the source axis + * + * Set absinfo for the selected destination axis by copying it from + * the specified source input device's source axis. + * This is useful to e.g. setup a pen/stylus input-device for combined + * touchscreen/pen hardware where the pen uses the same coordinates as + * the touchscreen. + */ +void input_copy_abs(struct input_dev *dst, unsigned int dst_axis, + const struct input_dev *src, unsigned int src_axis) +{ + /* src must have EV_ABS and src_axis set */ + if (WARN_ON(!(test_bit(EV_ABS, src->evbit) && + test_bit(src_axis, src->absbit)))) + return; + + /* + * input_alloc_absinfo() may have failed for the source. Our caller is + * expected to catch this when registering the input devices, which may + * happen after the input_copy_abs() call. + */ + if (!src->absinfo) + return; + + input_set_capability(dst, EV_ABS, dst_axis); + if (!dst->absinfo) + return; + + dst->absinfo[dst_axis] = src->absinfo[src_axis]; +} +EXPORT_SYMBOL(input_copy_abs); + +/** + * 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_values() 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->inhibited) { + /* + * Device is already opened and/or inhibited, + * so we can exit immediately and report success. + */ + goto out; + } + + if (dev->open) { + retval = dev->open(dev); + if (retval) { + dev->users--; + handle->open--; + /* + * Make sure we are not delivering any more events + * through this handle + */ + synchronize_rcu(); + goto out; + } + } + + if (dev->poller) + input_dev_poller_start(dev->poller); + + 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->inhibited) { + if (dev->poller) + input_dev_poller_stop(dev->poller); + if (dev->close) + dev->close(dev); + } + + if (!--handle->open) { + /* + * synchronize_rcu() makes sure that input_pass_values() + * 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 bool input_dev_release_keys(struct input_dev *dev) +{ + bool need_sync = false; + int code; + + lockdep_assert_held(&dev->event_lock); + + if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) { + for_each_set_bit(code, dev->key, KEY_CNT) { + input_handle_event(dev, EV_KEY, code, 0); + need_sync = true; + } + } + + return need_sync; +} + +/* + * 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. + */ + if (input_dev_release_keys(dev)) + input_handle_event(dev, EV_SYN, SYN_REPORT, 1); + + 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; + } + } + + if (*old_keycode <= KEY_MAX) { + __clear_bit(*old_keycode, dev->keybit); + for (i = 0; i < dev->keycodemax; i++) { + if (input_fetch_keycode(dev, i) == *old_keycode) { + __set_bit(*old_keycode, dev->keybit); + /* Setting the bit twice is useless, so break */ + break; + } + } + } + + __set_bit(ke->keycode, dev->keybit); + 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 (old_keycode > KEY_MAX) { + dev_warn(dev->dev.parent ?: &dev->dev, + "%s: got too big old keycode %#x\n", + __func__, old_keycode); + } else if (test_bit(EV_KEY, dev->evbit) && + !is_event_supported(old_keycode, dev->keybit, KEY_MAX) && + __test_and_clear_bit(old_keycode, dev->key)) { + /* + * We have to use input_event_dispose() here directly instead + * of input_handle_event() because the key we want to release + * here is considered no longer supported by the device and + * input_handle_event() will ignore it. + */ + input_event_dispose(dev, INPUT_PASS_TO_HANDLERS, + EV_KEY, old_keycode, 0); + input_event_dispose(dev, INPUT_PASS_TO_HANDLERS | INPUT_FLUSH, + EV_SYN, SYN_REPORT, 1); + } + + out: + spin_unlock_irqrestore(&dev->event_lock, flags); + + return retval; +} +EXPORT_SYMBOL(input_set_keycode); + +bool input_match_device_id(const struct input_dev *dev, + const struct input_device_id *id) +{ + if (id->flags & INPUT_DEVICE_ID_MATCH_BUS) + if (id->bustype != dev->id.bustype) + return false; + + if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR) + if (id->vendor != dev->id.vendor) + return false; + + if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT) + if (id->product != dev->id.product) + return false; + + if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION) + if (id->version != dev->id.version) + return false; + + if (!bitmap_subset(id->evbit, dev->evbit, EV_MAX) || + !bitmap_subset(id->keybit, dev->keybit, KEY_MAX) || + !bitmap_subset(id->relbit, dev->relbit, REL_MAX) || + !bitmap_subset(id->absbit, dev->absbit, ABS_MAX) || + !bitmap_subset(id->mscbit, dev->mscbit, MSC_MAX) || + !bitmap_subset(id->ledbit, dev->ledbit, LED_MAX) || + !bitmap_subset(id->sndbit, dev->sndbit, SND_MAX) || + !bitmap_subset(id->ffbit, dev->ffbit, FF_MAX) || + !bitmap_subset(id->swbit, dev->swbit, SW_MAX) || + !bitmap_subset(id->propbit, dev->propbit, INPUT_PROP_MAX)) { + return false; + } + + return true; +} +EXPORT_SYMBOL(input_match_device_id); + +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 (input_match_device_id(dev, id) && + (!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 (in_compat_syscall()) { + 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 __poll_t 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 EPOLLIN | EPOLLRDNORM; + } + + 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_putc(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_puts(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 proc_ops input_devices_proc_ops = { + .proc_open = input_proc_devices_open, + .proc_poll = input_proc_devices_poll, + .proc_read = seq_read, + .proc_lseek = seq_lseek, + .proc_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 proc_ops input_handlers_proc_ops = { + .proc_open = input_proc_handlers_open, + .proc_read = seq_read, + .proc_lseek = seq_lseek, + .proc_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_proc_ops); + if (!entry) + goto fail1; + + entry = proc_create("handlers", 0, proc_bus_input_dir, + &input_handlers_proc_ops); + 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 int input_inhibit_device(struct input_dev *dev); +static int input_uninhibit_device(struct input_dev *dev); + +static ssize_t inhibited_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct input_dev *input_dev = to_input_dev(dev); + + return scnprintf(buf, PAGE_SIZE, "%d\n", input_dev->inhibited); +} + +static ssize_t inhibited_store(struct device *dev, + struct device_attribute *attr, const char *buf, + size_t len) +{ + struct input_dev *input_dev = to_input_dev(dev); + ssize_t rv; + bool inhibited; + + if (strtobool(buf, &inhibited)) + return -EINVAL; + + if (inhibited) + rv = input_inhibit_device(input_dev); + else + rv = input_uninhibit_device(input_dev); + + if (rv != 0) + return rv; + + return len; +} + +static DEVICE_ATTR_RW(inhibited); + +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, + &dev_attr_inhibited.attr, + NULL +}; + +static const 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 const 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 const 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, + &input_poller_attribute_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->poller); + 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); + if (input_dev_release_keys(dev)) + input_handle_event(dev, EV_SYN, SYN_REPORT, 1); + + spin_unlock_irqrestore(&dev->event_lock, flags); + mutex_unlock(&dev->mutex); +} +EXPORT_SYMBOL(input_reset_device); + +static int input_inhibit_device(struct input_dev *dev) +{ + mutex_lock(&dev->mutex); + + if (dev->inhibited) + goto out; + + if (dev->users) { + if (dev->close) + dev->close(dev); + if (dev->poller) + input_dev_poller_stop(dev->poller); + } + + spin_lock_irq(&dev->event_lock); + input_mt_release_slots(dev); + input_dev_release_keys(dev); + input_handle_event(dev, EV_SYN, SYN_REPORT, 1); + input_dev_toggle(dev, false); + spin_unlock_irq(&dev->event_lock); + + dev->inhibited = true; + +out: + mutex_unlock(&dev->mutex); + return 0; +} + +static int input_uninhibit_device(struct input_dev *dev) +{ + int ret = 0; + + mutex_lock(&dev->mutex); + + if (!dev->inhibited) + goto out; + + if (dev->users) { + if (dev->open) { + ret = dev->open(dev); + if (ret) + goto out; + } + if (dev->poller) + input_dev_poller_start(dev->poller); + } + + dev->inhibited = false; + spin_lock_irq(&dev->event_lock); + input_dev_toggle(dev, true); + spin_unlock_irq(&dev->event_lock); + +out: + mutex_unlock(&dev->mutex); + return ret; +} + +#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. + */ + if (input_dev_release_keys(input_dev)) + input_handle_event(input_dev, EV_SYN, SYN_REPORT, 1); + + /* 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. + */ + if (input_dev_release_keys(input_dev)) + input_handle_event(input_dev, EV_SYN, SYN_REPORT, 1); + + 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 const 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(*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); + timer_setup(&dev->timer, NULL, 0); + 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(*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_timestamp - set timestamp for input events + * @dev: input device to set timestamp for + * @timestamp: the time at which the event has occurred + * in CLOCK_MONOTONIC + * + * This function is intended to provide to the input system a more + * accurate time of when an event actually occurred. The driver should + * call this function as soon as a timestamp is acquired ensuring + * clock conversions in input_set_timestamp are done correctly. + * + * The system entering suspend state between timestamp acquisition and + * calling input_set_timestamp can result in inaccurate conversions. + */ +void input_set_timestamp(struct input_dev *dev, ktime_t timestamp) +{ + dev->timestamp[INPUT_CLK_MONO] = timestamp; + dev->timestamp[INPUT_CLK_REAL] = ktime_mono_to_real(timestamp); + dev->timestamp[INPUT_CLK_BOOT] = ktime_mono_to_any(timestamp, + TK_OFFS_BOOT); +} +EXPORT_SYMBOL(input_set_timestamp); + +/** + * input_get_timestamp - get timestamp for input events + * @dev: input device to get timestamp from + * + * A valid timestamp is a timestamp of non-zero value. + */ +ktime_t *input_get_timestamp(struct input_dev *dev) +{ + const ktime_t invalid_timestamp = ktime_set(0, 0); + + if (!ktime_compare(dev->timestamp[INPUT_CLK_MONO], invalid_timestamp)) + input_set_timestamp(dev, ktime_get()); + + return dev->timestamp; +} +EXPORT_SYMBOL(input_get_timestamp); + +/** + * 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) +{ + if (type < EV_CNT && input_max_code[type] && + code > input_max_code[type]) { + pr_err("%s: invalid code %u for type %u\n", __func__, code, + type); + dump_stack(); + return; + } + + 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); + __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("%s: unknown type %u (code %u)\n", __func__, 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); +} + +/* + * 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(struct timer_list *t) +{ + struct input_dev *dev = from_timer(dev, t, timer); + unsigned long flags; + + spin_lock_irqsave(&dev->event_lock, flags); + + if (!dev->inhibited && + test_bit(dev->repeat_key, dev->key) && + is_event_supported(dev->repeat_key, dev->keybit, KEY_MAX)) { + + input_set_timestamp(dev, ktime_get()); + input_handle_event(dev, EV_KEY, dev->repeat_key, 2); + input_handle_event(dev, EV_SYN, SYN_REPORT, 1); + + if (dev->rep[REP_PERIOD]) + mod_timer(&dev->timer, jiffies + + msecs_to_jiffies(dev->rep[REP_PERIOD])); + } + + spin_unlock_irqrestore(&dev->event_lock, flags); +} + +/** + * 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.function = input_repeat_key; + dev->rep[REP_DELAY] = delay; + dev->rep[REP_PERIOD] = period; +} +EXPORT_SYMBOL(input_enable_softrepeat); + +bool input_device_enabled(struct input_dev *dev) +{ + lockdep_assert_held(&dev->mutex); + + return !dev->inhibited && dev->users > 0; +} +EXPORT_SYMBOL_GPL(input_device_enabled); + +/** + * 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 (test_bit(EV_ABS, dev->evbit) && !dev->absinfo) { + dev_err(&dev->dev, + "Absolute device without dev->absinfo, refusing to register\n"); + return -EINVAL; + } + + if (dev->devres_managed) { + devres = devres_alloc(devm_input_device_unregister, + sizeof(*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; + + if (dev->poller) + input_dev_poller_finalize(dev->poller); + + 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); |