[问答]

怎样在rk3288_firefly.dts添加设备节点呢

问答对人有帮助，内容完整，我也想知道答案 0 怎样在rk3288_firefly.dts添加设备节点呢？ 0
2022-3-4 07:11:22　　评论淘帖0 邀请回答您可以邀请以下用户，快速回答问题 × liutiefu 该类别下有 26 个回答。邀请回答 tigerwang711 该类别下有 20 个回答。邀请回答 ze55me 该类别下有 20 个回答。邀请回答 zhuzb0754 该类别下有 19 个回答。邀请回答杀狼000 该类别下有 19 个回答。邀请回答冰箱洗衣机该类别下有 18 个回答。邀请回答 YYXIAO 该类别下有 18 个回答。邀请回答安德森大该类别下有 17 个回答。邀请回答 CDCNKA 该类别下有 17 个回答。邀请回答 jjll652 该类别下有 17 个回答。邀请回答河神大人该类别下有 17 个回答。邀请回答 mede1001 该类别下有 17 个回答。邀请回答 YOYOOO 该类别下有 16 个回答。邀请回答麻酱该类别下有 16 个回答。邀请回答世态薄凉该类别下有 16 个回答。邀请回答熊本熊该类别下有 16 个回答。邀请回答 wang21cj 该类别下有 15 个回答。邀请回答 dfgsdf 该类别下有 15 个回答。邀请回答 szj0213 该类别下有 15 个回答。邀请回答梅利号该类别下有 15 个回答。邀请回答举报 wufan931111 相关推荐 • 为什么Firefly-RK3288主板烧写Android固件会失败呢 1536 • 在RK3288下怎样去添加PCF8563 RTC驱动支持呢 1280 • 在编译的rk3288中怎样加入edp dts配置呢 1134 • 怎样在Windows10系统下为Firefly-RK3288烧写固件呢 2785 • 如何去实现RK3288与LVDS屛的适配设计呢 1020 • 怎样去安装Flint OS for Firefly-RK3288系统呢 1760 • android dts配置_RK3288的过程是怎样的？ 847 • 如何去处理RK3288 Linux内核设备树的问题 2299 • 怎样使用RK3288的板子去刷linux ubuntu16的固件呢 2274 • 怎样去搭建一种Firefly-RK3288的编译环境呢 1787 2个回答

答案对人有帮助，有参考价值 0 1.时钟树 2.需要控制的LED的GPIO引脚 GPIO8_A1,找到对应的时钟控制描述通过Adress maping 找到这个寄存器的地址：0xFF760000 + 0x0198 时钟使能：CRU_CLKGATE14_CON (0xFF760000 + 0x0198); IO复用： GRF_GPIO8A_IOMUX (0xFF770000 + 0x0080); IO方向： GPIO8_SWPORTA_DDR (0xFF7F0000 + 0x0004); IO数据: GPIO8_SWPORTA_DR (0xFF7F0000 + 0x0000,); 在rk3288_firefly.dts添加设备节点 myled-node { xxx_led = "led_for_test"; #address-cells = <1>; #size-cells = <1>; compatible = "rk3288_testled"; status = "okay"; reg = < 0xFF760198 4 /* 时钟使能/ 0xFF770080 4 / IO 复用/ 0xFF7F0004 4 / 设置方向/ 0xFF7F0000 4>; / 数据设置/ }; 然后在内核根目录下 make dtbs,然后更换这个文件： /boot/rk3288-freﬂy.dtb #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define DTSLED_CNT 1 / 设备号个数 / #define DTSLED_NAME "rk3288_dtsled" / 名字 / #define LEDOFF 0 / 关灯 / #define LEDON 1 / 开灯 / / 设备结构体 / struct dtsled_dev{ dev_t devid; / 设备号 / struct cdev cdev; / cdev / struct class class; /* 类 / struct device device; /* 设备 / int major; / 主设备号 / int minor; / 次设备号 / struct device_node nd; /* 设备节点 / }; struct dtsled_dev rk3288_dtsled; / led设备 / / 映射后的寄存器虚拟地址指针 / static void __iomem CRU_CLKGATE14_CON; static void __iomem * GRF_GPIO8A_IOMUX ; static void __iomem * GPIO8A_SWPORTA_DDR; static void __iomem * GPIO8A_SWPORTA_DR ; void led_switch(u8 sta) { u32 val =0; if(sta == LEDON) { val = readl(GPIO8A_SWPORTA_DR); val &= ~(1<<1); writel(val,GPIO8A_SWPORTA_DR); //GPIO8_A1输出低电平 } else if(sta == LEDOFF) { val = readl(GPIO8A_SWPORTA_DR); val \|= (1<<1); writel(val,GPIO8A_SWPORTA_DR); //GPIO8_A1输出高电平 } } /* * @description : 打开设备 * @param – inode : 传递给驱动的 inode * @param – filp : 设备文件,file 结构体有个叫做 private_data 的成员变量 * 一般在 open 的时候将 private_data 指向设备结构体。 * @return : 0 成功;其他失败 / static int led_open(struct inode inode, struct file * filp) { filp->private_data = &rk3288_dtsled; //设置私有数据 return 0; } static ssize_t led_read(struct file filp, char __user buf,size_t cnt, loff_t off_t) { return 0; } static ssize_t led_write(struct file filp, const char __user buf,size_t cnt, loff_t off_t) { int ret; unsigned char databuf[1]; unsigned char ledstat; ret = copy_from_user(databuf,buf,cnt); if(ret < 0) { printk("kernel write failed n"); return -1; } ledstat = databuf[0]; if(ledstat == LEDON) { led_switch(LEDON); } else if(ledstat == LEDOFF) { led_switch(LEDOFF); } return 0; } static int led_release(struct inode inode, struct file filp) { printk("led release n"); return 0; } static struct file_operations rk3288_dtsled_fops ={ .owner = THIS_MODULE, .open = led_open, .read = led_read, .write = led_write, .release = led_release, }; /* * 驱动的入口函数 / static int __init led_init(void) { int ret; const char str; unsigned int regdata[14]; struct property proper; unsigned int val =0; / 获取设备树中的属性数据 / //1.获取设备节点 rk3288_dtsled.nd = of_find_node_by_path("/myled-node"); if(rk3288_dtsled.nd == NULL) { printk("myled-node can not find n"); } else { printk("myled-node has been found n"); } //2.获取属性内容 proper = of_find_property(rk3288_dtsled.nd,"compatible",NULL); if(proper == NULL) { printk("compatible property find failed n"); } else { printk("compatible = %s n",(char )proper->value); } /* 3、获取 status 属性内容 */ ret = of_property_read_string(rk3288_dtsled.nd, "status", &str); if(ret < 0){ printk("status read failed!rn"); } else { printk("status = %srn",str); }

2022-3-4 14:51:03 评论举报李大帅

答案对人有帮助，有参考价值 0 /* 4、获取 reg 属性内容 / ret = of_property_read_u32_array(rk3288_dtsled.nd, "reg", regdata, 8); if(ret < 0) { printk("reg property read failed!rn"); } else { u8 i = 0; printk("reg data:rn"); for(i = 0; i < 8; i++) printk("%#X ", regdata); printk("rn"); } { struct platform_device op = of_find_device_by_node(rk3288_dtsled.nd); printk("num_resources: %d n", op->num_resources); } #if 1 /* 1、寄存器地址映射 / CRU_CLKGATE14_CON = ioremap(regdata[0], regdata[1]); GRF_GPIO8A_IOMUX = ioremap(regdata[2], regdata[3]); GPIO8A_SWPORTA_DDR = ioremap(regdata[4], regdata[5]); GPIO8A_SWPORTA_DR = ioremap(regdata[6], regdata[7]); #else / 初始化LED / CRU_CLKGATE14_CON = of_iomap(rk3288_dtsled.nd, 0); //GRF_GPIO8A_IOMUX = of_iomap(rk3288_dtsled.nd, 1); //GPIO8A_SWPORTA_DDR = of_iomap(rk3288_dtsled.nd, 2); //GPIO8A_SWPORTA_DR = of_iomap(rk3288_dtsled.nd, 3); #endif #if 1 //使能GPIO8的时钟 val = readl(CRU_CLKGATE14_CON); val &= ~(0<<8); val \|= (1<<(8+16)); writel(val,CRU_CLKGATE14_CON); //设置GPIO8_A1的复用功能 val = readl(GRF_GPIO8A_IOMUX); val &= ~(0<<2); val \|= (3<<(2+16)); writel(val,GRF_GPIO8A_IOMUX); //设置GPIO8_A1的方向输出 val = readl(GPIO8A_SWPORTA_DDR); val \|= 1<<1; writel(val,GPIO8A_SWPORTA_DDR); //默认关闭led val = readl(GPIO8A_SWPORTA_DR); val \|= (1<<1); writel(val,GPIO8A_SWPORTA_DR); #endif / 注册字符设备驱动 / //1.创建设备号 if(rk3288_dtsled.major){ rk3288_dtsled.devid = MKDEV(rk3288_dtsled.major,0); register_chrdev_region(rk3288_dtsled.devid,DTSLED_CNT,DTSLED_NAME); }else{ alloc_chrdev_region(&rk3288_dtsled.devid,0, DTSLED_CNT, DTSLED_NAME); //申请设备号 rk3288_dtsled.major = MAJOR(rk3288_dtsled.devid); rk3288_dtsled.minor = MINOR(rk3288_dtsled.devid); } printk("rk3288_dtsled major=%d,minor=%d n",rk3288_dtsled.major,rk3288_dtsled.minor); //初始化cdev rk3288_dtsled.cdev.owner = THIS_MODULE; cdev_init(&rk3288_dtsled.cdev,&rk3288_dtsled_fops); //添加一个cdev cdev_add(&rk3288_dtsled.cdev,rk3288_dtsled.devid,DTSLED_CNT); //创建类 rk3288_dtsled.class = class_create(THIS_MODULE,DTSLED_NAME); if(IS_ERR(rk3288_dtsled.class)) return PTR_ERR(rk3288_dtsled.class); //创建设备 rk3288_dtsled.device = device_create(rk3288_dtsled.class,NULL,rk3288_dtsled.devid, NULL,DTSLED_NAME); if(IS_ERR(rk3288_dtsled.device)){ return PTR_ERR(rk3288_dtsled.device); } return 0; } static void __exit led_exit(void) { iounmap(CRU_CLKGATE14_CON); iounmap(GRF_GPIO8A_IOMUX); iounmap(GPIO8A_SWPORTA_DDR); iounmap(GPIO8A_SWPORTA_DR); //注销字符设备驱动 cdev_del(&rk3288_dtsled.cdev); //删除cdev unregister_chrdev_region(rk3288_dtsled.devid,DTSLED_CNT); //注销设备号 device_destroy(rk3288_dtsled.class,rk3288_dtsled.devid); class_destroy(rk3288_dtsled.class); } module_init(led_init); module_exit(led_exit); MODULE_LICENSE("GPL"); //这里of_iomap会报错：先留个坑，后面解决······································· #include "stdio.h" #include "unistd.h" #include "sys/types.h" #include "sys/stat.h" #include "fcntl.h" #include "stdlib.h" #include "string.h" #define LEDON 1 #define LEDOFF 0 int main(int argc, char argv[]) { int fd,retvalue; char *filename; unsigned char databuf[1]; if(argc != 3) { printf("error usage n"); return -1; } filename = argv[1]; fd = open(filename,O_RDWR); if(fd < 0) { printf("file %s open failed n", filename); } databuf[0] = atoi(argv[2]); retvalue = write(fd,databuf,sizeof(databuf)); if(retvalue < 0) { printf("led write failed n"); close(fd); return -1; } retvalue = close(fd); printf("test nor n"); } Makefile文件 # 1. 使用不同的开发板内核时, 一定要修改KERN_DIR # 2. KERN_DIR中的内核要事先配置、编译, 为了能编译内核, 要先设置下列环境变量: # 2.1 ARCH, 比如: export ARCH=arm64 # 2.2 CROSS_COMPILE, 比如: export CROSS_COMPILE=aarch64-linux-gnu- # 2.3 PATH, 比如: export PATH=$PATH:/home/book/100ask_roc-rk3399-pc/ToolChain-6.3.1/gcc-linaro-6.3.1-2017.05-x86_64_aarch64-linux-gnu/bin # 注意: 不同的开发板不同的编译器上述3个环境变量不一定相同, # 请参考各开发板的高级用户使用手册 KERN_DIR = /home/book/mysamba/RK_3288_SDK/linux-4.4 all: make -C $(KERN_DIR) M=`pwd` modules $(CROSS_COMPILE)gcc -o ledtest ledtest.c clean: make -C $(KERN_DIR) M=`pwd` modules clean rm -rf modules.order rm -f ledtest # 参考内核源码drivers/char/ipmi/Makefile # 要想把a.c, b.c编译成ab.ko, 可以这样指定: # ab-y := a.o b.o # obj-m += ab.o obj-m += rk3288_led_driver.o

2022-3-4 14:51:06 评论举报刘伟