Android getevent用法详解

getevent 指令用于获取 input 输入事件，比如获取按键上报信息、获取触摸屏上报信息等。

指令源码路径：/system/core/toolbox/getevent.c

getevent -h：查看 getevent 帮助信息

root@rk3288:/ # getevent -h
getevent -h
Usage: getevent [-t] [-n] [-s switchmask] [-S] [-v [mask]] [-d] [-p] [-i] [-l] [-q] [-c count] [-r] [device]
    -t: show time stamps
    -n: don't print newlines
    -s: print switch states for given bits
    -S: print all switch states
    -v: verbosity mask (errs=, dev=, name=, info=, vers=, pos. events=, props=)
    -d: show HID descriptor, if available
    -p: show possible events (errs, dev, name, pos. events)
    -i: show all device info and possible events
    -l: label event types and names in plain text
    -q: quiet (clear verbosity mask)
    -c: print given number of events then exit
    -r: print rate events are received

getevent：显示当前有那些输入设备，数量与 /dev/input 目录下相同

root@rk3288:/ # getevent
getevent
add device : /dev/input/event3
  name:     "ILITEK Multi-Touch-V3020"
add device : /dev/input/event2
  name:     "PC Camera"
add device : /dev/input/event1
  name:     "gsensor"
add device : /dev/input/event0
  name:     "rk29-keypad"

root@rk3288:/ # ls /dev/input
ls /dev/input
event0
event1
event2
event3

查看默认上报数据

root@rk3288:/ # getevent /dev/input/event3
getevent /dev/input/event3

  00001a9f
 014a 

  00001a9f

  ffffffff
 014a
  

-t：显示时间戳

// 读取 event3 数据（触摸屏）
root@rk3288:/ # getevent -t /dev/input/event3
getevent -t /dev/input/event3
[    1141.248434]   0000000e
[    1141.248434]   00002cd4
[    1141.248434]   00001a09
[    1141.248434]  014a
[    1141.248434]   00002cd4
[    1141.248434]   00001a09
[    1141.248434]
[    1141.322181]   ffffffff
[    1141.322181]  014a
[    1141.322181]   

-n：不换行打印

root@rk3288:/ # getevent -n /dev/input/event3
getevent -n /dev/input/event3
    00002f000003  00001a4e0001 014a   00002f000003  00001a4e0000    ffffffff0001 014a       00002e880003  000019b80001 014a   00002e880003  000019b80000    ffffffff0001 014a       00002d700003  00001a000001 014a   00002d700003  00001a000000    ffffffff0001 014a       00002d080003  000019a50001 014a   00002d080003  000019a50000    ffffffff0001 014a 

-s：显示指定位的开关状态

root@rk3288:/ # getevent -s5 /dev/input/event3
getevent -s5 /dev/input/event3

-S：显示所有位的开关状态

root@rk3288:/ # getevent -S /dev/input/event3
getevent -S /dev/input/event3
 

-v：根据 mask 值显示相关信息，执行后会一直显示上报数据

errs=1, dev=2, name=4, info=8, vers=16, pos. events=32, props=64

默认显示 dev| name| info| vers = 30;

root@rk3288:/ # getevent -v /dev/input/event3
getevent -v /dev/input/event3
add device : /dev/input/event3
  bus:
  vendor    222a
  product   004d
  version
  name:     "ILITEK Multi-Touch-V3020"
  location: "usb-ff540000.usb-1.3/input0"
  id:       ""
  version:  1.0.

root@rk3288:/ # getevent -v30 /dev/input/event3
getevent -v30 /dev/input/event3
add device : /dev/input/event3
  bus:
  vendor    222a
  product   004d
  version
  name:     "ILITEK Multi-Touch-V3020"
  location: "usb-ff540000.usb-1.3/input0"
  id:       ""
  version:  1.0.

root@rk3288:/ # getevent -v2 /dev/input/event3
getevent -v2 /dev/input/event3
add device : /dev/input/event3

root@rk3288:/ # getevent -v8 /dev/input/event3
getevent -v8 /dev/input/event3
  bus:
  vendor    222a
  product   004d
  version
  location: "usb-ff540000.usb-1.3/input0"
  id:       ""

root@rk3288:/ # getevent -v16 /dev/input/event3
getevent -v16 /dev/input/event3
  version:  1.0.

root@rk3288:/ # getevent -v32 /dev/input/event3
getevent -v32 /dev/input/event3
  events:
    KEY (): 014a
    ABS ():   : value , min , max , fuzz , flat , resolution
                  : value , min , max , fuzz , flat , resolution
                002f  : value , min , max , fuzz , flat , resolution
                  : value , min , max , fuzz , flat , resolution
                  : value , min , max , fuzz , flat , resolution
                  : value , min , max , fuzz , flat , resolution 

-d：如果设备可用，显示设备隐藏的描述信息

-p：显示设备支持的事件类型和编码方式

root@rk3288:/ # getevent -p /dev/input/event3
getevent -p /dev/input/event3
add device : /dev/input/event3
  name:     "ILITEK Multi-Touch-V3020"
  events:
    KEY (): 014a
    ABS ():   : value , min , max , fuzz , flat , resolution
                  : value , min , max , fuzz , flat , resolution
                002f  : value , min , max , fuzz , flat , resolution
                  : value , min , max , fuzz , flat , resolution
                  : value , min , max , fuzz , flat , resolution
                  : value , min , max , fuzz , flat , resolution
  input props:
    INPUT_PROP_DIRECT

-i：显示设备的所有信息和支持的事件，比 -p 显示更多信息

root@rk3288:/ # getevent -i /dev/input/event3

-l：以文本形式输出事件类型和名称，比 -t 更清楚直观

// 读取 event3 数据（触摸屏）
root@rk3288:/ # getevent -l /dev/input/event3
getevent -l /dev/input/event3
// 事件类型      事件码              事件值
EV_ABS       ABS_MT_TRACKING_ID   0000000f
EV_ABS       ABS_MT_POSITION_X    00002bbc
EV_ABS       ABS_MT_POSITION_Y    00001b6d
EV_KEY       BTN_TOUCH            DOWN
EV_ABS       ABS_X                00002bbc
EV_ABS       ABS_Y                00001b6d
EV_SYN       SYN_REPORT
EV_ABS       ABS_MT_TRACKING_ID   ffffffff
EV_KEY       BTN_TOUCH            UP
EV_SYN       SYN_REPORT           

-q：暂时不会使用

-c：打印固定数量的事件并退出

root@rk3288:/ # getevent -c  /dev/input/event3
getevent -c  /dev/input/event3

  000038a4
  000008f5
 014a
  000038a4
  000008f5

  ffffffff
 014a
  

-r：显示事件上报速率

// 检测触摸屏报点速率
root@rk3288:/ # getevent -r /dev/input/event3
getevent -r /dev/input/event3

  000030d8

 014a
  000030d8

   rate
  ffffffff
 014a
   rate 

参数可以组合使用，一次性查看需要的触摸屏信息

root@rk3288:/ # getevent -tlr /dev/input/event3
getevent -tlr /dev/input/event3
[    2514.550104] EV_ABS       ABS_MT_TRACKING_ID   0000001c
[    2514.550104] EV_ABS       ABS_MT_POSITION_X    00002dac
[    2514.550104] EV_ABS       ABS_MT_POSITION_Y    000018ca
[    2514.550104] EV_KEY       BTN_TOUCH            DOWN
[    2514.550104] EV_ABS       ABS_X                00002dac
[    2514.550104] EV_ABS       ABS_Y                000018ca
[    2514.550104] EV_SYN       SYN_REPORT                        rate
[    2514.638845] EV_ABS       ABS_MT_TRACKING_ID   ffffffff
[    2514.638845] EV_KEY       BTN_TOUCH            UP
[    2514.638845] EV_SYN       SYN_REPORT                        rate