Board:全志R16
SDK:Android KitKat 4.4.2、linux-3.4
開發内容:自定義按鍵名為SOCHIP_EXT1,接在R16開發闆的GPIOB7口。
1.先在linux-3.4/inlcude/linux/input.h
添加自定義按鍵#define SOCHIP_EXT1 0x2e8
注意該鍵值最好不要跟系統的鍵值沖突,然後編寫linux下的key driver代碼。
#include <linux/module.h>
#include <linux/init.h>
#include <linux/input.h>
#include <linux/irq.h>
#include <mach/irqs.h>
#include <linux/interrupt.h>
#include <asm-generic/errno.h>
#include <asm-generic/errno-base.h>
#include <linux/gpio.h>
#include <mach/gpio.h>
#include <linux/slab.h>
#include <linux/timer.h>
#include <linux/param.h>
#include <linux/jiffies.h>
#include <linux/ioport.h>
#include <linux/io.h>
/* mach/sys_config.h for allwinner platform */
#include <mach/sys_config.h>
#define KEYDEV_NAME "mykey"
#define MY_KEY KEY_SOCHIP_EXT1
static int g_key_gpio;
static int g_key_irq;
static struct timer_list *key_timer = NULL;
static struct input_dev *key_dev = NULL;
static void __iomem *key_reg;
/* 按鍵處理終端函數 */
static irqreturn_t isr_key_func(int irq, void *arg)
{
printk(KERN_EMERG "key intretupt is comming ...\n");
/* HZ的值可linux源碼目錄下的.config可知,我這裡是CONFIG_HZ=100
* HZ代表1s鐘中斷發生的次數,此處HZ / 5 相當于 1/5秒 即 200ms
* 增加定時器的目的是 按鍵去抖動
*/
mod_timer(key_timer, jiffies + (HZ / ));
return IRQ_HANDLED;
}
/* 定時器處理函數 */
static void timer_handler(unsigned long arg)
{
unsigned int val;
val = gpio_get_value(g_key_gpio);
printk("val = %d\n", val);
if(val == ){
printk("key up ... \n");
input_report_key(key_dev, MY_KEY, );
input_sync(key_dev);
}else if(val == ){
printk("key down ...\n");
input_report_key(key_dev, MY_KEY, );
input_sync(key_dev);
}
}
/* 擷取系統配置 */
static int fetch_sysconfig(void)
{
script_item_u val;
script_item_value_type_e type;
/* 擷取sys_config.fex中的主鍵值位key, 子健值位key_gpio的資源
* 如:
* [key]
* key_gpio = port:PB07<4><default><default><default>
*/
type = script_get_item("key", "key_gpio", &val);
if(SCIRPT_ITEM_VALUE_TYPE_PIO != type) {
printk(KERN_ERR "get key_gpio from sys_config.fex is err!");
return -EINAL;
}
g_key_gpio = val.gpio.gpio;
/* 聲明io */
gpio_request(g_key_gpio, "KEY_INT_GPIO");
//根據IO擷取中斷ID
g_key_irq = gpio_to_irq(g_key_gpio);
if(g_key_irq == -ENXIO)
{
printk(KERN_EMERG "gpio_to_irq failed!\n");
return -ENXIO;
}
}
static int __init key_init(void)
{
int ret = ;
printk("hello key driver\n");
//初始化定時器
key_timer = kzalloc(sizeof(struct timer_list), GFP_KERNEL);
if(!key_timer){
printk("kzalloc timer is failed!\n");
ret = -ENOMEM;
goto ERR1;
}
init_timer(key_timer);
key_timer->function = timer_handler;//定時服務函數
key_timer->expires = jiffies + (HZ / );//目前時間 + 定時時間
add_timer(key_timer);//添加定時器
//input結構體申請記憶體
key_dev = input_allocate_device();
if(!key_dev){
printk(KERN_EMERG "key: input_allocate_device failed!\n");
ret = -ENOMEM;
goto ERR2;
}
key_dev->name = KEYDEV_NAME; //輸入裝置名字
key_dev->phys = "input22"; //裝置節點名稱
key_dev->id.bustype = BUS_HOST; //裝置辨別ID屬性 用于與事件處理層進行比對
key_dev->id.vendor = ;
key_dev->id.product = ;
key_dev->id.version = ;
set_bit(EV_KEY, key_dev->evbit);//設定支援的事件類型為key
set_bit(MY_KEY, key_dev->keybit);//設定裝置支援按鍵類型為MYKEY
ret = fetch_sysconfig();
if(ret){
printk("fetch sysconfig is failed!\n");
goto ERR4;
}
//2.申請中斷
if(request_irq(g_key_irq, isr_key_func, IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING, "key", NULL)){
ret = -EBUSY;
printk(KERN_EMERG "request irq failed!\n");
goto ERR4;
}
//3.向input子系統注冊device
ret = input_register_device(key_dev);
if(ret){
printk(KERN_EMERG "input register device failed!\n");
goto ERR5;
}
return ;
ERR5:
free_irq(g_key_irq, NULL);
ERR4:
gpio_free(g_key_gpio);
ERR3:
input_free_device(key_dev);
ERR2:
kfree(key_timer);
ERR1:
return ret;
}
static void __exit key_exit(void)
{
del_timer(key_timer); //删除定時器
kfree(key_timer);//釋放記憶體
free_irq(g_key_irq, NULL); //釋放中斷id
gpio_free(g_key_gpio); //第二種方式釋放申請的記憶體資源
input_unregister_device(key_dev);//解input注冊
printk("goodbye key driver\n");
}
module_init(key_init);
module_exit(key_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("orange");
MODULE_DESCRIPTION("key driver");
2.修改xxx.kl安卓下的按鍵映射檔案,R16平台SDK對應的kl檔案在android/device/softwinner/xxx/configs/sunxi-keyboard.kl,也可通過cat /proc/bus/input/devices 可找到相應的驅動名。(其他kl檔案可在frameworks//base/data/keyboards/中找到)添加key 744 SOCHIP_EXT1。
3.修改framework層的相關檔案,R16平台SDK相關檔案對應的路徑如下:
=>android/frameworks/native/include/input/KeycodeLabels.h中添加如下對應的代碼:
{ "ASSIST", },
{ "BRIGHTNESS_DOWN", },
{ "BRIGHTNESS_UP", },
{ "MEDIA_AUDIO_TRACK", },
{ "SOCHIP_EXT1" , }, ==>此處添加
=>android/frameworks/native/include/android/keycodes.h中添加如下對應的代碼:
265 AKEYCODE_ASSIST = 219,
266 AKEYCODE_BRIGHTNESS_DOWN = 220,
267 AKEYCODE_BRIGHTNESS_UP = 221,
268 AKEYCODE_MEDIA_AUDIO_TRACK = 222,
269 AKEYCODE_SOCHIP_EXT1 = 223, ==>此處添加
=>android/frameworks/base/core/res/res/values/attrs.xml中添加如下對應的代碼:
<enum name="KEYCODE_ASSIST" value="219" />
<enum name="KEYCODE_BRIGHTNESS_DOWN" value="220" />
<enum name="KEYCODE_BRIGHTNESS_UP" value="221" />
<enum name="KEYCODE_MEDIA_AUDIO_TRACK" value="222" />
<enum name="KEYCODE_SOCHIP_EXT1" value="223" /> ==>此處添加
=>android/frameworks/base/core/java/android/view/KeyEvent.java 此檔案有兩處修改,分别如下:
第一處修改:
public static final int KEYCODE_BRIGHTNESS_UP = ;
/** Key code constant: Audio Track key
633 * Switches the audio tracks. */
public static final int KEYCODE_MEDIA_AUDIO_TRACK = ;
public static final int KEYCODE_SOCHIP_EXT1 = ; ==>此處添加
private static final int LAST_KEYCODE = KEYCODE_SOCHIP_EXT1;==>此處若LAST_KEYCODE對應的上一行是什麼按鍵就指派什麼。
第二處修改:
names.append(KEYCODE_ASSIST, "KEYCODE_ASSIST");
names.append(KEYCODE_BRIGHTNESS_DOWN, "KEYCODE_BRIGHTNESS_DOWN");
names.append(KEYCODE_BRIGHTNESS_UP, "KEYCODE_BRIGHTNESS_UP");
names.append(KEYCODE_MEDIA_AUDIO_TRACK, "KEYCODE_MEDIA_AUDIO_TRACK");
names.append(KEYCODE_SOCHIP_EXT1, "KEYCODE_SOCHIP_EXT1");==>此處添加
=>android/device/softwinner/astar-evb/configs/sunxi-keyboard.kl中添加如下
key HOME WAKE
key BACK WAKE
key MENU WAKE_DROPPED
key VOLUME_UP
key VOLUME_DOWN
key SOCHIP_EXT1 ==>此處添加
=>android/frameworks/native/libs/input/Input.cpp =>修改 bool KeyEvent::isSystemKey(int32_t keyCode) ,添加AKEYCODE_SOCHIP_EXT1 ,如添加了代表此按鍵為系統按鍵。
case AKEYCODE_SEARCH:
case AKEYCODE_BRIGHTNESS_DOWN:
case AKEYCODE_BRIGHTNESS_UP:
case AKEYCODE_MEDIA_AUDIO_TRACK:
case AKEYCODE_SOCHIP_EXT1:
最後切記執行make update-api 把剛剛修改的内容更新,可在frameworks/base/api/current.txt找到更新後添加到裡面的按鍵内容,如本文,我們可以搜尋SOCHIP_EXT1,找到的内容如下:
field public static final int KEYCODE_SLASH = ; // 0x4c
field public static final int KEYCODE_SOCHIP_EXT1 = ; // 0xdf ==>此處
field public static final int KEYCODE_SOFT_LEFT = ; // 0x1
field public static final int KEYCODE_SOFT_RIGHT = ; // 0x2
若沒有執行make update-api是找不到你所添加的按鍵對應的内容,最後編譯、打包、燒錄,至此添加自定義按鍵成功,相關解析按鍵布局的kl檔案可在frameworks/base/services/input/EventHub.cpp。