Linux Kernel input设备之描述

/**

 * struct input_dev - represents an input device * @name: name of the device * @phys: physical path to the device in the system hierarchy * @uniq: unique identification code for the device (if device has it) * @id: id of the device (struct input_id) * @propbit: bitmap of device properties and quirks * @evbit: bitmap of types of events supported by the device (EV_KEY, *EV_REL, etc.) * @keybit: bitmap of keys/buttons this device has * @relbit: bitmap of relative axes for the device * @absbit: bitmap of absolute axes for the device * @mscbit: bitmap of miscellaneous events supported by the device * @ledbit: bitmap of leds present on the device * @sndbit: bitmap of sound effects supported by the device * @ffbit: bitmap of force feedback effects supported by the device * @swbit: bitmap of switches present on the device * @hint_events_per_packet: average number of events generated by the *device in a packet (between EV_SYN/SYN_REPORT events). Used by *event handlers to estimate size of the buffer needed to hold *events. * @keycodemax: size of keycode table * @keycodesize: size of elements in keycode table * @keycode: map of scancodes to keycodes for this device * @getkeycode: optional legacy method to retrieve current keymap. * @setkeycode: optional method to alter current keymap, used to implement *sparse keymaps. If not supplied default mechanism will be used. *The method is being called while holding event_lock and thus must *not sleep * @ff: force feedback structure associated with the device if device *supports force feedback effects * @repeat_key: stores key code of the last key pressed; used to implement *software autorepeat * @timer: timer for software autorepeat * @rep: current values for autorepeat parameters (delay, rate) * @mt: pointer to multitouch state * @absinfo: array of &struct input_absinfo elements holding information *about absolute axes (current value, min, max, flat, fuzz, *resolution) * @key: reflects current state of device's keys/buttons * @led: reflects current state of device's LEDs * @snd: reflects current state of sound effects * @sw: reflects current state of device's switches * @open: this method is called when the very first user calls *input_open_device(). The driver must prepare the device *to start generating events (start polling thread, *request an IRQ, submit URB, etc.) * @close: this method is called when the very last user calls *input_close_device(). * @flush: purges the device. Most commonly used to get rid of force *feedback effects loaded into the device when disconnecting *from it * @event: event handler for events sent _to_ the device, like EV_LED *or EV_SND. The device is expected to carry out the requested *action (turn on a LED, play sound, etc.) The call is protected *by @event_lock and must not sleep * @grab: input handle that currently has the device grabbed (via *EVIOCGRAB ioctl). When a handle grabs a device it becomes sole *recipient for all input events coming from the device * @event_lock: this spinlock is taken when input core receives *and processes a new event for the device (in input_event()). *Code that accesses and/or modifies parameters of a device *(such as keymap or absmin, absmax, absfuzz, etc.) after device *has been registered with input core must take this lock. * @mutex: serializes calls to open(), close() and flush() methods * @users: stores number of users (input handlers) that opened this *device. It is used by input_open_device() and input_close_device() *to make sure that dev->open() is only called when the first *user opens device and dev->close() is called when the very *last user closes the device * @going_away: marks devices that are in a middle of unregistering and *causes input_open_device*() fail with -ENODEV. * @dev: driver model's view of this device * @h_list: list of input handles associated with the device. When *accessing the list dev->mutex must be held * @node: used to place the device onto input_dev_list * @num_vals: number of values queued in the current frame * @max_vals: maximum number of values queued in a frame * @vals: array of values queued in the current frame * @devres_managed: indicates that devices is managed with devres framework *and needs not be explicitly unregistered or freed. */struct input_dev {const char *name;const char *phys;const char *uniq;struct input_id id;unsigned long propbit[BITS_TO_LONGS(INPUT_PROP_CNT)];unsigned long evbit[BITS_TO_LONGS(EV_CNT)];unsigned long keybit[BITS_TO_LONGS(KEY_CNT)];unsigned long relbit[BITS_TO_LONGS(REL_CNT)];unsigned long absbit[BITS_TO_LONGS(ABS_CNT)];unsigned long mscbit[BITS_TO_LONGS(MSC_CNT)];unsigned long ledbit[BITS_TO_LONGS(LED_CNT)];unsigned long sndbit[BITS_TO_LONGS(SND_CNT)];unsigned long ffbit[BITS_TO_LONGS(FF_CNT)];unsigned long swbit[BITS_TO_LONGS(SW_CNT)];unsigned int hint_events_per_packet;unsigned int keycodemax;unsigned int keycodesize;void *keycode;int (*setkeycode)(struct input_dev *dev,  const struct input_keymap_entry *ke,  unsigned int *old_keycode);int (*getkeycode)(struct input_dev *dev,  struct input_keymap_entry *ke);struct ff_device *ff;unsigned int repeat_key;struct timer_list timer;int rep[REP_CNT];struct input_mt *mt;struct input_absinfo *absinfo;unsigned long key[BITS_TO_LONGS(KEY_CNT)];unsigned long led[BITS_TO_LONGS(LED_CNT)];unsigned long snd[BITS_TO_LONGS(SND_CNT)];unsigned long sw[BITS_TO_LONGS(SW_CNT)];int (*open)(struct input_dev *dev);void (*close)(struct input_dev *dev);int (*flush)(struct input_dev *dev, struct file *file);int (*event)(struct input_dev *dev, unsigned int type, unsigned int code, int value);struct input_handle __rcu *grab;spinlock_t event_lock;struct mutex mutex;unsigned int users;bool going_away;struct device dev;struct list_headh_list;struct list_headnode;unsigned int num_vals;unsigned int max_vals;struct input_value *vals;bool devres_managed;};