RK3399 GPIO3引脚如何通过mmap去控制

Chip Platform Rockchip
1

通过mmap方式可以看读写gpio1引脚，可以读gpio3，但无法写gpio3，对应的CRU寄存器也不能写，不知道个人有没有遇到的或者官方是否有相应的文档。此外，通过io命令也不能直接修改

2

没有人这样用的吗

3

本帖最后由 iamFirefly 于 2017-11-7 15:20 编辑 

</blockquote><div class="blockcode"><blockquote><blockquote>#include <sys/mman.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

#define MMAP_PATH        "/dev/mem"
#define RK3399_GPIO_DATA  0x0000
#define RK3399_GPIO_DIRC  0x0004
#define DIRC_OUTPUT 1
#define DIRC_INPUT 0
#define DATA_LOW 0
#define DATA_HIGH 1

static uint8_t* gpio3_clocken_base_reg = NULL;
static uint8_t* gpio3_iomux_base_reg = NULL;
static uint8_t* gpio3_mmap_base_reg = NULL;

int gpio_mmap_fd = 0;

int gpio_mmap(void)
{
       if ((gpio_mmap_fd = open(MMAP_PATH, O_RDWR|O_SYNC)) < 0) {
           fprintf(stderr, "unable to open mmap file");
           return -1;
        }
   return 0;
}
//=============GPIO 3
int getGpio3State()
{
      uint32_t con,iom,data,dirc;
     printf("\n================\n      GPIO3 Info    \n");
   /* clock en   */
    gpio3_clocken_base_reg = (uint8_t*) mmap(NULL, 4096, PROT_READ | PROT_WRITE,
    MAP_SHARED, gpio_mmap_fd,0xff760000);

  con = *(volatile uint32_t *)(gpio3_clocken_base_reg+0x037c);
  printf(" the clock config reg is %0x \n",con);

    /* iomux */
  gpio3_iomux_base_reg = (uint8_t*) mmap(NULL, 4096*4, PROT_READ | PROT_WRITE,
  MAP_SHARED, gpio_mmap_fd,0xff770000);
 iom = *(volatile uint32_t *)(gpio3_iomux_base_reg+0xe01c);
   printf(" the  iomux reg is %0x \n",iom);

    /* input or output  */

    gpio3_mmap_base_reg = (uint8_t*) mmap(NULL, 4096, PROT_READ | PROT_WRITE,MAP_SHARED, gpio_mmap_fd,0xFF788000);

      dirc =  *(volatile uint32_t *)(gpio3_mmap_base_reg+RK3399_GPIO_DIRC);
       printf(" the direct reg is %0x \n",dirc);

       data = *(volatile uint32_t *)(gpio3_mmap_base_reg+RK3399_GPIO_DATA);
       printf("before set the data reg  is %0x \n",data);

}

void setGpio3State()
{
    uint32_t con,iom,data,dirc;
4

代码没发全，接楼上

void setGpio3State()
{
	uint32_t con,iom,data,dirc;

       	*(volatile uint32_t *)(gpio3_mmap_base_reg+RK3399_GPIO_DATA)=0x00008000;
    data = *(volatile uint32_t *)(gpio3_mmap_base_reg+RK3399_GPIO_DATA);
       printf("after set the data  is %0x \n",data);

}

int main()
{

   int i;
   gpio_mmap();

   printf("\n=========== \n     gpio-3 info:   \n");
   getGpio3State();
   setGpio3State();

	return 0;
}
5

问题就是读完data寄存器的值后，在向data寄存器写入0x00008000，寄存器内的值未发生改变，写不了