Name struct input_dev — represents an input device Synopsis struct input_dev { const char * name; //name of the device const char * phys; //physical path to the device in the system hierarchy const char * uniq; //unique identification code for the device (if device has it) struct input_id id; //id of the device (struct input_id) unsigned long evbit[BITS_TO_LONGS(EV_CNT)]; //bitmap of types of events supported by the device (EV_KEY, EV_REL, etc.) unsigned long keybit[BITS_TO_LONGS(KEY_CNT)]; //bitmap of keys/buttons this device has unsigned long relbit[BITS_TO_LONGS(REL_CNT)]; //bitmap of relative axes for the device unsigned long absbit[BITS_TO_LONGS(ABS_CNT)]; //bitmap of absolute axes for the device unsigned long mscbit[BITS_TO_LONGS(MSC_CNT)]; //bitmap of miscellaneous events supported by the device unsigned long ledbit[BITS_TO_LONGS(LED_CNT)]; //bitmap of leds present on the device unsigned long sndbit[BITS_TO_LONGS(SND_CNT)]; //bitmap of sound effects supported by the device unsigned long ffbit[BITS_TO_LONGS(FF_CNT)]; //bitmap of force feedback effects supported by the device unsigned long swbit[BITS_TO_LONGS(SW_CNT)]; //bitmap of switches present on the device unsigned int keycodemax; //size of keycode table unsigned int keycodesize; //size of elements in keycode table void * keycode; //map of scancodes to keycodes for this device /*optional method to alter current keymap, used to implement sparse keymaps. If not supplied default mechanism will be used*/ int (* setkeycode) (struct input_dev *dev, int scancode, int keycode); /*optional method to retrieve current keymap. If not supplied default mechanism will be used*/ int (* getkeycode) (struct input_dev *dev, int scancode, int *keycode); struct ff_device * ff; //force feedback structure associated with the device if device supports force feedback effects unsigned int repeat_key; //stores key code of the last key pressed; used to implement software autorepeat struct timer_list timer; //timer for software autorepeat int sync; //set to 1 when there were no new events since last EV_SYNC int abs[ABS_MAX + 1]; //current values for reports from absolute axes int rep[REP_MAX + 1]; //current values for autorepeat parameters (delay, rate) unsigned long key[BITS_TO_LONGS(KEY_CNT)]; //reflects current state of device's keys/buttons unsigned long led[BITS_TO_LONGS(LED_CNT)]; //reflects current state of device's LEDs unsigned long snd[BITS_TO_LONGS(SND_CNT)]; //reflects current state of sound effects unsigned long sw[BITS_TO_LONGS(SW_CNT)]; //reflects current state of device's switches int absmax[ABS_MAX + 1]; //maximum values for events coming from absolute axes int absmin[ABS_MAX + 1]; //minimum values for events coming from absolute axes int absfuzz[ABS_MAX + 1]; //describes noisiness for axes int absflat[ABS_MAX + 1]; //size of the center flat position (used by joydev) /*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.) */ int (* open) (struct input_dev *dev); void (* close) (struct input_dev *dev); //this method is called when the very last user calls input_close_device. /*purges the device. Most commonly used to get rid of force feedback effects loaded into the device when disconnecting from it */ int (* flush) (struct input_dev *dev, struct file *file); /*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 */ int (* event) (struct input_dev *dev, unsigned int type, unsigned int code, int value); /*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 */ struct input_handle * grab; /*this spinlock is 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. */ spinlock_t event_lock; struct mutex mutex; //serializes calls to open, close and flush methods /*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->closeis called when the very last user closes the device */ unsigned int users; int going_away; //marks devices that are in a middle of unregistering and causes input_open_device*() fail with -ENODEV. struct device dev; //driver model's view of this device struct list_head h_list; //list of input handles associated with the device. When accessing the list dev->mutex must be held struct list_head node; //used to place the device onto input_dev_list };