C++
#include <linux/init.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/miscdevice.h>
#include <linux/fs.h>
#include <linux/errno.h>
#include <linux/gpio/consumer.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/gpio_keys.h>
#include <linux/of_irq.h>
#include <linux/gpio.h>
#include <linux/property.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <linux/slab.h>
#include <linux/device.h>
#define DRIVER_NAME "imx6ul,dts-tree"
static int devtree_probe(struct platform_device
* pdev)
{
struct fwnode_handle *child;
const char *p1,*p2[3];
u32 p3[2],value;
u8 testmac[6];
int i=0;
printk(KERN_INFO "\n**********devtree_probe******************\n");
device_property_read_string(&pdev->dev,"test-string",&p1);
printk("devtree_probe node test-string
is: %s\n",p1);
device_property_read_string_array(&pdev->dev,
"test-strings", p2, 3);
printk("devtree_probe node test-strings
is: %s%s%s\n",p2[0],p2[1],p2[2]);
device_property_read_u32(&pdev->dev,"test-u32",&value);
printk("devtree_probe node test-u32 is:
<%d>\n",value);
device_property_read_u32_array(&pdev->dev,
"test-u32s", p3, 2);
printk("devtree_probe node test-u32s is:
<%d>,<%d>\n",p3[0],p3[1]);
device_property_read_string(&pdev->dev,"compatible",&p1);
printk("devtree_probe node compatible is:
%s\n",p1);
device_property_read_string(&pdev->dev,"status",&p1);
printk("devtree_probe node status is: %s\n",p1);
printk(" \n * devtree_probe child node
\n");
device_for_each_child_node(&pdev->dev,
child){
printk("*************childnode%d*************\n",i++);
fwnode_property_read_string(child,"test-string",&p1);
printk("childnode test-string is: %s\n",p1);
fwnode_property_read_string_array(child,"test-strings",p2,3);
printk("childnode test-strings is: %s%s%s\n",p2[0],p2[1],p2[2]);
fwnode_property_read_u32_array(child,"test-u32",&value,1);
printk("childnode test-u32 is: <%d>\n",value);
fwnode_property_read_u32_array(child,"test-u32s",p3,2);
printk("childnode test-u32s is: <%d>,<%d>\n",p3[0],p3[1]);
fwnode_property_read_u8_array(child,"test-u8s",testmac,6);
printk("childnode test-u32s is: [%x,%x,%x,%x,%x,%x]\n",testmac[0],testmac[1],testmac[2],testmac[3],testmac[4],testmac[5]);
}
return 0;
}
static int devtree_remove(struct platform_device
* pdev)
{
printk(KERN_INFO "devtree_remove\n");
return 0;
}
static const struct of_device_id of_devtree_dt_match[]
= {
{.compatible = DRIVER_NAME},
{},
};
MODULE_DEVICE_TABLE(of,of_devtree_dt_match);
static struct platform_driver devtree_test_driver
= {
.probe = devtree_probe,
.remove = devtree_remove,
.driver = {
.name = DRIVER_NAME,
.owner = THIS_MODULE,
.of_match_table = of_devtree_dt_match,
},
};
static int devtree_test_init(void)
{
int num=0,i=0,value;
const char *p1;
struct device_node *node1,*childnode1;
u32 p2[2];
u8 testmac[6];
pr_warn(KERN_INFO "^^^^^^^^^^^^^^^^^^^devtree_test_init^^^^^^^^^^^
\n");
printk(KERN_INFO "^^^^^^^^^^^^^^^^^^^devtree_test_init^^^^^^^^^^^
\n");
printk("\n*************devtree init start
***************\n");
node1 = of_find_node_by_path("/dts-tree1");
if(node1 == NULL){
printk("of_find_node_by_path failed\n");
return -ENODEV;
}
else{
printk("of_find_node_by_path dts-tree1
ok\n");
}
//read string
of_property_read_string(node1, "test-string",
&p1);
printk("dts-tree1 node :test-string is:
%s\n",p1);
//read strings
num = of_property_count_strings(node1, "test-strings");
printk("dts-tree1 node test-strings num
is: %d\n",num);
for(i=0;i<num;i++){
of_property_read_string_index(node1,"test-strings",i,&p1);
printk("%s",p1);
}
//read string "compatible"
of_property_read_string(node1, "compatible",
&p1);
printk("dts-tree1 node compatible is: %s\n",p1);
//read string "status"
of_property_read_string(node1, "status",
&p1);
printk("dts-tree1 node status is: %s\n",p1);
//read u32 "test-u32"
of_property_read_u32(node1,"test-u32",&value);
printk("dts-tree1 node test-u32 is: <%d>\n",value);
//read u32s test-u32s
of_property_read_u32_array(node1, "test-u32s",
p2, 2);
printk("dts-tree1 node test-u32s is: <%d>,<%d>\n",p2[0],p2[1]);
//read u8s test-u8s
of_property_read_u8_array(node1, "test-u8s",
testmac, 6);
printk("dts-tree1 node test-u8s is: <%x>,<%x>,<%x>,<%x>,<%x>,<%x>\n",testmac[0],testmac[1],testmac[2],testmac[3],testmac[4],testmac[5]);
//get "dts_child_node1" device node
childnode1 = of_get_child_by_name(node1,"dts_child_node1");
if(childnode1 == NULL){
printk("of_get_child_by_name failed\n");
return -ENODEV;
}
printk("of_get_child_by_name dts_child_node1
ok\n");
of_property_read_string(childnode1, "test-string",
&p1);
printk("dts_child_node1 node test-string
is: %s\n",p1);
return platform_driver_register(&devtree_test_driver);
}
static void devtree_test_exit(void)
{
printk(KERN_INFO "\ndevtree_test_exit\n");
platform_driver_unregister(&devtree_test_driver);
}
module_init(devtree_test_init);
module_exit(devtree_test_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("zheng");
