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Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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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/export.h>#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/pm.h>#include <linux/poll.h>#include <linux/device.h>#include <linux/kstrtox.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 256static 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){ timer_delete(&dev->timer);}
/* * Pass values first through all filters and then, if event has not been * filtered out, through all open handles. This order is achieved by placing * filters at the head of the list of handles attached to the device, and * placing regular handles at the tail of the list. * * 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);
scoped_guard(rcu) { handle = rcu_dereference(dev->grab); if (handle) { count = handle->handle_events(handle, vals, count); break; }
list_for_each_entry_rcu(handle, &dev->h_list, d_node) { if (handle->open) { count = handle->handle_events(handle, vals, count); if (!count) break; } } }
/* 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_new_slot = false; 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]; is_new_slot = mt->slot != dev->absinfo[ABS_MT_SLOT].value; } 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_new_slot) { dev->absinfo[ABS_MT_SLOT].value = 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 (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){ if (is_event_supported(type, dev->evbit, EV_MAX)) { guard(spinlock_irqsave)(&dev->event_lock); input_handle_event(dev, type, code, value); }}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;
if (is_event_supported(type, dev->evbit, EV_MAX)) { guard(spinlock_irqsave)(&dev->event_lock); guard(rcu)();
grab = rcu_dereference(dev->grab); if (!grab || grab == handle) input_handle_event(dev, type, code, value);
}}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 = kzalloc_objs(*dev->absinfo, ABS_CNT); 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;
scoped_cond_guard(mutex_intr, return -EINTR, &dev->mutex) { if (dev->grab) return -EBUSY;
rcu_assign_pointer(dev->grab, handle); }
return 0;}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;
guard(mutex)(&dev->mutex); __input_release_device(handle);}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 error;
scoped_cond_guard(mutex_intr, return -EINTR, &dev->mutex) { if (dev->going_away) return -ENODEV;
handle->open++;
if (handle->handler->passive_observer) return 0;
if (dev->users++ || dev->inhibited) { /* * Device is already opened and/or inhibited, * so we can exit immediately and report success. */ return 0; }
if (dev->open) { error = dev->open(dev); if (error) { dev->users--; handle->open--; /* * Make sure we are not delivering any more * events through this handle. */ synchronize_rcu(); return error; } }
if (dev->poller) input_dev_poller_start(dev->poller); }
return 0;}EXPORT_SYMBOL(input_open_device);
int input_flush_device(struct input_handle *handle, struct file *file){ struct input_dev *dev = handle->dev;
scoped_cond_guard(mutex_intr, return -EINTR, &dev->mutex) { if (dev->flush) return dev->flush(dev, file); }
return 0;}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;
guard(mutex)(&dev->mutex);
__input_release_device(handle);
if (!handle->handler->passive_observer) { 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(); }}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() */ scoped_guard(mutex, &dev->mutex) dev->going_away = true;
guard(spinlock_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;}
/** * 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;}
/** * input_default_setkeycode - default setkeycode method * @dev: input device which keymap is being updated. * @ke: new keymap entry. * @old_keycode: pointer to the location where old keycode should be stored. * * This function is the default implementation of &input_dev.setkeycode() * method. It is typically used when a driver does not provide its own * implementation, but it is also exported so drivers can extend it. * * The function must be called with &input_dev.event_lock held. * * Return: 0 on success, or a negative error code on failure. */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;
lockdep_assert_held(&dev->event_lock);
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;}EXPORT_SYMBOL(input_default_setkeycode);
/** * 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){ guard(spinlock_irqsave)(&dev->event_lock);
return dev->getkeycode(dev, ke);}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 int old_keycode; int error;
if (ke->keycode > KEY_MAX) return -EINVAL;
guard(spinlock_irqsave)(&dev->event_lock);
error = dev->setkeycode(dev, ke, &old_keycode); if (error) return error;
/* 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); }
return 0;}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++) { 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_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);}
struct input_seq_state { unsigned short pos; bool mutex_acquired; int input_devices_state;};
static __poll_t input_proc_devices_poll(struct file *file, poll_table *wait){ struct seq_file *seq = file->private_data; struct input_seq_state *state = seq->private;
poll_wait(file, &input_devices_poll_wait, wait); if (state->input_devices_state != input_devices_state) { state->input_devices_state = input_devices_state; return EPOLLIN | EPOLLRDNORM; }
return 0;}
static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos){ struct input_seq_state *state = seq->private; int error;
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){ struct input_seq_state *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_private(file, &input_devices_seq_ops, sizeof(struct input_seq_state));}
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_private,};
static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos){ struct input_seq_state *state = seq->private; int error;
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){ struct input_seq_state *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); struct input_seq_state *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_private(file, &input_handlers_seq_ops, sizeof(struct input_seq_state));}
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_private,};
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 sysfs_emit(buf, "%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, const unsigned long *bm, unsigned int min_bit, unsigned int max_bit){ int bit = min_bit; int len = 0;
len += snprintf(buf, max(size, 0), "%c", name); for_each_set_bit_from(bit, bm, max_bit) len += snprintf(buf + len, max(size - len, 0), "%X,", bit); return len;}
static int input_print_modalias_parts(char *buf, int size, int full_len, const struct input_dev *id){ int len, klen, remainder, space;
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);
/* * Calculate the remaining space in the buffer making sure we * have place for the terminating 0. */ space = max(size - (len + 1), 0);
klen = input_print_modalias_bits(buf + len, size - len, 'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX); len += klen;
/* * If we have more data than we can fit in the buffer, check * if we can trim key data to fit in the rest. We will indicate * that key data is incomplete by adding "+" sign at the end, like * this: * "k1,2,3,45,+,". * * Note that we shortest key info (if present) is "k+," so we * can only try to trim if key data is longer than that. */ if (full_len && size < full_len + 1 && klen > 3) { remainder = full_len - len; /* * We can only trim if we have space for the remainder * and also for at least "k+," which is 3 more characters. */ if (remainder <= space - 3) { /* * We are guaranteed to have 'k' in the buffer, so * we need at least 3 additional bytes for storing * "+," in addition to the remainder. */ for (int i = size - 1 - remainder - 3; i >= 0; i--) { if (buf[i] == 'k' || buf[i] == ',') { strcpy(buf + i + 1, "+,"); len = i + 3; /* Not counting '\0' */ break; } } } }
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);
return len;}
static int input_print_modalias(char *buf, int size, const struct input_dev *id){ int full_len;
/* * Printing is done in 2 passes: first one figures out total length * needed for the modalias string, second one will try to trim key * data in case when buffer is too small for the entire modalias. * If the buffer is too small regardless, it will fill as much as it * can (without trimming key data) into the buffer and leave it to * the caller to figure out what to do with the result. */ full_len = input_print_modalias_parts(NULL, 0, 0, id); return input_print_modalias_parts(buf, size, full_len, id);}
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); if (len < PAGE_SIZE - 2) len += snprintf(buf + len, PAGE_SIZE - len, "\n");
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, const 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 sysfs_emit(buf, "%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 (kstrtobool(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 sysfs_emit(buf, "%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, const 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, const 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;}
/* * This is a pretty gross hack. When building uevent data the driver core * may try adding more environment variables to kobj_uevent_env without * telling us, so we have no idea how much of the buffer we can use to * avoid overflows/-ENOMEM elsewhere. To work around this let's artificially * reduce amount of memory we will use for the modalias environment variable. * * The potential additions are: * * SEQNUM=18446744073709551615 - (%llu - 28 bytes) * HOME=/ (6 bytes) * PATH=/sbin:/bin:/usr/sbin:/usr/bin (34 bytes) * * 68 bytes total. Allow extra buffer - 96 bytes */#define UEVENT_ENV_EXTRA_LEN 96
static int input_add_uevent_modalias_var(struct kobj_uevent_env *env, const struct input_dev *dev){ int len;
if (add_uevent_var(env, "MODALIAS=")) return -ENOMEM;
len = input_print_modalias(&env->buf[env->buflen - 1], (int)sizeof(env->buf) - env->buflen - UEVENT_ENV_EXTRA_LEN, dev); if (len >= ((int)sizeof(env->buf) - env->buflen - UEVENT_ENV_EXTRA_LEN)) 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(const struct device *device, struct kobj_uevent_env *env){ const 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){ guard(mutex)(&dev->mutex); guard(spinlock_irqsave)(&dev->event_lock);
input_dev_toggle(dev, true); if (input_dev_release_keys(dev)) input_handle_event(dev, EV_SYN, SYN_REPORT, 1);}EXPORT_SYMBOL(input_reset_device);
static int input_inhibit_device(struct input_dev *dev){ guard(mutex)(&dev->mutex);
if (dev->inhibited) return 0;
if (dev->users) { if (dev->close) dev->close(dev); if (dev->poller) input_dev_poller_stop(dev->poller); }
scoped_guard(spinlock_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); }
dev->inhibited = true;
return 0;}
static int input_uninhibit_device(struct input_dev *dev){ int error;
guard(mutex)(&dev->mutex);
if (!dev->inhibited) return 0;
if (dev->users) { if (dev->open) { error = dev->open(dev); if (error) return error; } if (dev->poller) input_dev_poller_start(dev->poller); }
dev->inhibited = false;
scoped_guard(spinlock_irq, &dev->event_lock) input_dev_toggle(dev, true);
return 0;}
static int input_dev_suspend(struct device *dev){ struct input_dev *input_dev = to_input_dev(dev);
guard(spinlock_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);
return 0;}
static int input_dev_resume(struct device *dev){ struct input_dev *input_dev = to_input_dev(dev);
guard(spinlock_irq)(&input_dev->event_lock);
/* Restore state of LEDs and sounds, if any were active. */ input_dev_toggle(input_dev, true);
return 0;}
static int input_dev_freeze(struct device *dev){ struct input_dev *input_dev = to_input_dev(dev);
guard(spinlock_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);
return 0;}
static int input_dev_poweroff(struct device *dev){ struct input_dev *input_dev = to_input_dev(dev);
guard(spinlock_irq)(&input_dev->event_lock);
/* Turn off LEDs and sounds, if any are active. */ input_dev_toggle(input_dev, false);
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,};
static const struct device_type input_dev_type = { .groups = input_dev_attr_groups, .release = input_dev_release, .uevent = input_dev_uevent, .pm = pm_sleep_ptr(&input_dev_pm_ops),};
static char *input_devnode(const struct device *dev, umode_t *mode){ return kasprintf(GFP_KERNEL, "input/%s", dev_name(dev));}
const 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_obj(*dev); if (!dev) return NULL;
/* * Start with space for SYN_REPORT + 7 EV_KEY/EV_MSC events + 2 spare, * see input_estimate_events_per_packet(). We will tune the number * when we register the device. */ dev->max_vals = 10; dev->vals = kzalloc_objs(*dev->vals, dev->max_vals); if (!dev->vals) { kfree(dev); return NULL; }
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->dev.type = &input_dev_type; dev->dev.class = &input_class; device_initialize(&dev->dev); /* * From this point on we can no longer simply "kfree(dev)", we need * to use input_free_device() so that device core properly frees its * resources associated with the input device. */
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);
scoped_guard(mutex, &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));
timer_delete_sync(&dev->timer); list_del_init(&dev->node);
input_wakeup_procfs_readers(); }
if (dev->ff && dev->ff->stop) dev->ff->stop(dev->ff);
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 = timer_container_of(dev, t, timer);
guard(spinlock_irqsave)(&dev->event_lock);
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])); }}
/** * 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);
static int input_device_tune_vals(struct input_dev *dev){ struct input_value *vals; unsigned int packet_size; unsigned int max_vals;
packet_size = input_estimate_events_per_packet(dev); if (dev->hint_events_per_packet < packet_size) dev->hint_events_per_packet = packet_size;
max_vals = dev->hint_events_per_packet + 2; if (dev->max_vals >= max_vals) return 0;
vals = kcalloc(max_vals, sizeof(*vals), GFP_KERNEL); if (!vals) return -ENOMEM;
scoped_guard(spinlock_irq, &dev->event_lock) { dev->max_vals = max_vals; swap(dev->vals, vals); }
/* Because of swap() above, this frees the old vals memory */ kfree(vals);
return 0;}
/** * 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; 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);
error = input_device_tune_vals(dev); if (error) 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_devres_free;
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 = -EINTR; scoped_cond_guard(mutex_intr, goto err_device_del, &input_mutex) { 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(); }
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_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);
static int input_handler_check_methods(const struct input_handler *handler){ int count = 0;
if (handler->filter) count++; if (handler->events) count++; if (handler->event) count++;
if (count > 1) { pr_err("%s: only one event processing method can be defined (%s)\n", __func__, handler->name); return -EINVAL; }
return 0;}
/** * 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 = input_handler_check_methods(handler); if (error) return error;
scoped_cond_guard(mutex_intr, return -EINTR, &input_mutex) { 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(); }
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;
guard(mutex)(&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();}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;
guard(rcu)();
list_for_each_entry_rcu(handle, &handler->h_list, h_node) { retval = fn(handle, data); if (retval) return retval; }
return 0;}EXPORT_SYMBOL(input_handler_for_each_handle);
/* * An implementation of input_handle's handle_events() method that simply * invokes handler->event() method for each event one by one. */static unsigned int input_handle_events_default(struct input_handle *handle, struct input_value *vals, unsigned int count){ struct input_handler *handler = handle->handler; struct input_value *v;
for (v = vals; v != vals + count; v++) handler->event(handle, v->type, v->code, v->value);
return count;}
/* * An implementation of input_handle's handle_events() method that invokes * handler->filter() method for each event one by one and removes events * that were filtered out from the "vals" array. */static unsigned int input_handle_events_filter(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;
for (v = vals; v != vals + count; v++) { if (handler->filter(handle, v->type, v->code, v->value)) continue; if (end != v) *end = *v; end++; }
return end - vals;}
/* * An implementation of input_handle's handle_events() method that does nothing. */static unsigned int input_handle_events_null(struct input_handle *handle, struct input_value *vals, unsigned int count){ return count;}
/* * Sets up appropriate handle->event_handler based on the input_handler * associated with the handle. */static void input_handle_setup_event_handler(struct input_handle *handle){ struct input_handler *handler = handle->handler;
if (handler->filter) handle->handle_events = input_handle_events_filter; else if (handler->event) handle->handle_events = input_handle_events_default; else if (handler->events) handle->handle_events = handler->events; else handle->handle_events = input_handle_events_null;}
/** * 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;
input_handle_setup_event_handler(handle); /* * We take dev->mutex here to prevent race with * input_release_device(). */ scoped_cond_guard(mutex_intr, return -EINTR, &dev->mutex) { /* * 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); }
/* * 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(). */ scoped_guard(mutex, &dev->mutex) list_del_rcu(&handle->d_node);
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_alloc_range(&input_ida, legacy_base, legacy_base + legacy_num - 1, GFP_KERNEL); if (minor >= 0 || !allow_dynamic) return minor; }
return ida_alloc_range(&input_ida, INPUT_FIRST_DYNAMIC_DEV, INPUT_MAX_CHAR_DEVICES - 1, 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_free(&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);