// SPDX-License-Identifier: GPL-2.0-only /* * The input core * * Copyright (c) 1999-2002 Vojtech Pavlik */ #define pr_fmt(fmt) KBUILD_BASENAME ": " fmt #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "input-compat.h" #include "input-core-private.h" #include "input-poller.h" MODULE_AUTHOR("Vojtech Pavlik "); 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 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); rcu_read_lock(); handle = rcu_dereference(dev->grab); if (handle) { count = handle->handler->events(handle, vals, count); } else { list_for_each_entry_rcu(handle, &dev->h_list, d_node) if (handle->open) { count = handle->handler->events(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_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) { 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); } 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) { 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; } 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, }; 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(sizeof(*dev), GFP_KERNEL); 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 = kcalloc(dev->max_vals, sizeof(*dev->vals), GFP_KERNEL); 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); 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); 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; spin_lock_irq(&dev->event_lock); dev->max_vals = max_vals; swap(dev->vals, vals); spin_unlock_irq(&dev->event_lock); /* 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 = 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_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; } /* * An implementation of input_handler's events() method that simply * invokes handler->event() method for each event one by one. */ static unsigned int input_handler_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_handler's 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_handler_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_handler's events() method that does nothing. */ static unsigned int input_handler_events_null(struct input_handle *handle, struct input_value *vals, unsigned int count) { return count; } /** * 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; INIT_LIST_HEAD(&handler->h_list); if (handler->filter) handler->events = input_handler_events_filter; else if (handler->event) handler->events = input_handler_events_default; else if (!handler->events) handler->events = input_handler_events_null; error = mutex_lock_interruptible(&input_mutex); if (error) return error; 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_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);