Platform: Rockchip
OS: Android 7.1.2
Kernel: 3.10
需求：
通过在相关的kernel文件中建立文件节点，使adroid端app能直接与相关驱动文件交互，完成特定的驱动行为
实现：
第一步：实现驱动文件中建立文件节点
static ssize_t test_read_status(struct device* cd, struct device_attribute* attr,char *buf)
{
printk(KERN_EMERG "line:%d,%s is calledn", __LINE__, __FUNCTION__);
return 0;
}
static ssize_t test_write_status(struct device* cd, struct device_attribute *attr,const char* buf, size_t len){
int id;
//int dir = 1;
sscanf(buf, "%d", &id);
printk(KERN_ERR "test_write_status id=%dn",id);
return len;
}
static DEVICE_ATTR(test, S_IRUGO | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH| S_IWOTH, test_read_status, test_write_status);
static int test_create_sysfs(struct i2c_client *client)
{
int err;
struct device *dev = &(client->dev);
printk(KERN_EMERG "line:%d,%s is calledn", __LINE__, __FUNCTION__);
err = device_create_file(dev, &dev_attr_test);
return err;
}
第二步：在app中操作文件节点
private static final String SYS_FILE = "/sys/devices/20072000.i2c/i2c-0/0-0010/test";
private static final File mFile = new File(SYS_FILE);
public void Write2File(File file,String mode) {
Log.d(TAG,"Write2File,write mode = "+mode);
if((file == null) || (!file.exists()) || (mode == null)) return ;
try {
FileOutputStream fout = new FileOutputStream(file);
PrintWriter pWriter = new PrintWriter(fout);
pWriter.println(mode);
pWriter.flush();
pWriter.close();
fout.close();
} catch(IOException re) {
Log.d(TAG,"write error:"+re);
return;
}
}
public void test(){
Write2File(mFile, "1");
}
Platform: Rockchip
OS: Android 7.1.2
Kernel: 3.10
需求：
通过在相关的kernel文件中建立文件节点，使adroid端app能直接与相关驱动文件交互，完成特定的驱动行为
实现：
第一步：实现驱动文件中建立文件节点
static ssize_t test_read_status(struct device* cd, struct device_attribute* attr,char *buf)
{
printk(KERN_EMERG "line:%d,%s is calledn", __LINE__, __FUNCTION__);
return 0;
}
static ssize_t test_write_status(struct device* cd, struct device_attribute *attr,const char* buf, size_t len){
int id;
//int dir = 1;
sscanf(buf, "%d", &id);
printk(KERN_ERR "test_write_status id=%dn",id);
return len;
}
static DEVICE_ATTR(test, S_IRUGO | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH| S_IWOTH, test_read_status, test_write_status);
static int test_create_sysfs(struct i2c_client *client)
{
int err;
struct device *dev = &(client->dev);
printk(KERN_EMERG "line:%d,%s is calledn", __LINE__, __FUNCTION__);
err = device_create_file(dev, &dev_attr_test);
return err;
}
第二步：在app中操作文件节点
private static final String SYS_FILE = "/sys/devices/20072000.i2c/i2c-0/0-0010/test";
private static final File mFile = new File(SYS_FILE);
public void Write2File(File file,String mode) {
Log.d(TAG,"Write2File,write mode = "+mode);
if((file == null) || (!file.exists()) || (mode == null)) return ;
try {
FileOutputStream fout = new FileOutputStream(file);
PrintWriter pWriter = new PrintWriter(fout);
pWriter.println(mode);
pWriter.flush();
pWriter.close();
fout.close();
} catch(IOException re) {
Log.d(TAG,"write error:"+re);
return;
}
}
public void test(){
Write2File(mFile, "1");
}
举报
