在用户态控制GPIO的程序，省去了写驱动的麻烦，减少了系统调用， 直接将GPIO块的寄存器映射到用户空间，直接控制寄存器，提高了效率 本程序可直接用对应的cross compiler进行编译： arm-linux-gcc -o gpio_ctrl gpio_ctrl.c /* * gpio_ctrl.c: user mode software to control the GPIO of S3C2440 * Author Youri Zhang 2010-12-28 (yahui9635@gmail.com) * Reach the Author first before release this program. */ #include <stdio.h>#include <stdlib.h>#include <sys/mman.h>#include <fcntl.h>#include <unistd.h>#undef PAGE_SIZE#undef PAGE_MASK#define APP_NAME "gpio_ctrl"#define VERSION "1.0"#define BUILD_DATE __DATE__#define PAGE_SHIFT 12#define PAGE_SIZE (1<<PAGE_SHIFT) /* 4096byte Per Mapped Memory page */#define PAGE_MASK (~(PAGE_SIZE-1) )#define GPIO_EndAddr 0x560000DC#define GPIO_StartAddr 0x56000000#define CLKREG_StartAddr 0x4C000000 #define CLKREG_EndAddr 0x4C000018 #define CLKCON 0x0C#define REG(Addr) (*(volatile unsigned int*) (Addr))static char* GPIOConStatus[4] = {"INPUT", "OUTPUT", "SpecialUse", "Reserved"};static char* GPIODataStatus[2] = {"LOW", "HIGH"};static char* GPIOPullupStatus[2] = {"Enabled", "Disabled"};static void print_usage(void){ fprintf(stdout,"************Help information for %s*************\n",APP_NAME); fprintf(stdout,"[Usage] %s -[b:n:c:w:p:rsdh] <value>\n", APP_NAME); fprintf(stdout,"Version: %s, Date: %s, Author: Youri Zhang\n\n", VERSION, BUILD_DATE); fprintf(stdout,"\t-b : (Must use 1st)specify the GPIO Bank index\n\t\t==>GPA's index is 0, GPB's index is 1 ... GPH's index is 7, GPJ's index is 8\n"); fprintf(stdout,"\t-n : (Must use 2nd)specify the GPIO num in GPIO Bank\n"); fprintf(stdout,"\t-c : Config the GPIO type(GPA use)\n\t\t==>OUTPUT:'-c 0x00', Special use:'-c 0x01'\n"); fprintf(stdout,"\t-c : Config the GPIO type(GPB--J use)\n\t\t==>INPUT:'-c 0x00', OUTPUT:'-c 0x01', Special use:'-c 0x02', Reserved:'-c 0x03'\n"); fprintf(stdout,"\t-w : Write value to GPIO pin's Data_reg\n"); fprintf(stdout,"\t-p : Config value to GPIO pin's Pullup_reg\n\t\t==>Enable:'-p 0x00', Disable:'-p 0x01'\n"); fprintf(stdout,"\t-r : Read the GPIO pin Data_reg's value\n"); fprintf(stdout,"\t-s : Show the GPIO pin Config_reg's value\n"); fprintf(stdout,"\t-d : Display the GPIO pin Pullup_reg's value\n"); fprintf(stdout,"\t-h : This help information\n\n"); fprintf(stdout,"Ex:\tConfig GPG4 output & write 0 to GPG4 Data_reg&enable pullup&read Data_reg&show configure&show pullup\n\t\t==> (%s -b 6 -n 4 -c 1 -w 0 -p 0 -s -r -d)\n", APP_NAME); fprintf(stdout,"\t\t==> (%s -b 0x06 -n 0x04 -c 0x01 -w 0x00 -p 0x00 -s -r -d)\n\t\t--> both decimal and hexadecimal input are ok!\n", APP_NAME); fprintf(stdout,"Ex:\tConfig the GPA4 output and write 0 to GPG4 Data_reg\n\t\t==> (%s -b 0 -n 4 -c 0x00 -w 0)\n", APP_NAME); fprintf(stdout,"Ex:\tConfig the GPG4 output and read GPG4 Data_reg's value\n\t\t==> (%s -b 6 -n 4 -c 0x01 -r)\n", APP_NAME); fprintf(stdout,"Ex:\tConfig the GPG4 output and show GPG4 Config_reg's value\n\t\t==> (%s -b 6 -n 4 -c 0x01 -s)\n", APP_NAME);}/* enable PCLK(50Mhz) to GPIO Block */static void s3c2440_clkcon_init(void* REG_CLK){ REG((unsigned int)REG_CLK+CLKCON) |=0x2000; }static void s3c2440_gpio_cfgpin(void *Regaddr, unsigned int Addr_offset, unsigned int MaskBit, unsigned int Function){ unsigned int tmp=0; tmp=REG((unsigned int)Regaddr +Addr_offset); if(Addr_offset>0) { Function &= 3; tmp &= ~(3<<MaskBit); /*used for GPIO Bank B-J, which use the 2 bits Mask*/ } else { Function &= 1; tmp &= ~(1<<MaskBit); /*used for GPIO Bank A, which use the 1 bit Mask*/ } tmp|= (Function<<MaskBit); REG((unsigned int)Regaddr +Addr_offset)=tmp;}static unsigned int s3c2440_gpio_getcfg(void *Regaddr, unsigned int Addr_offset, unsigned int MaskBit){ unsigned int tmp=0; tmp=REG((unsigned int)Regaddr +Addr_offset); tmp >>= MaskBit; if(Addr_offset>0x0c) tmp &= 3; /*used for GPIO Bank B-J, which use the 2 bits Mask*/ else tmp &= 1; /*used for GPIO Bank A, which use the 1 bit Mask*/ return tmp;}static void s3c2440_gpio_setpin(void *Regaddr, unsigned int Addr_offset, unsigned int MaskBit, unsigned int to){ unsigned int tmp=0; tmp=REG((unsigned int)Regaddr +Addr_offset); tmp &= ~(1<<MaskBit); tmp |= (!!to<<MaskBit); REG((unsigned int)Regaddr +Addr_offset)=tmp; }static unsigned int s3c2440_gpio_getpin(void *Regaddr, unsigned int Addr_offset, unsigned int MaskBit){ unsigned int tmp=0; tmp=REG((unsigned int)Regaddr +Addr_offset); tmp &= (1<<MaskBit); return tmp?1:0;}static void s3c2440_gpio_pullup(void *Regaddr, unsigned int Addr_offset, unsigned int MaskBit, unsigned int to){ unsigned int tmp=0; tmp=REG((unsigned int)Regaddr +Addr_offset); tmp &= ~(1<<MaskBit); tmp |= !!to << MaskBit; REG((unsigned int)Regaddr +Addr_offset)=tmp;}static unsigned int s3c2440_gpio_getpull(void *Regaddr, unsigned int Addr_offset, unsigned int MaskBit){ unsigned int tmp=0; tmp=REG((unsigned int)Regaddr +Addr_offset); tmp &= (1<<MaskBit); return tmp?1:0;}int main(int argc, char* argv[]){ int fd=-1, opt = -1, Bank_num=-1, Addr_offset=-1, MaskBit=-1, Function=-1, to=-1,pullup=-1; void* GpioBase = NULL; void* CLKBASE = NULL; if(argc==2 && !strcmp(argv[1],"-h")) { print_usage(); exit(1); } else if(argc > 5 && argc < 15) { if(strcmp(argv[1],"-b") || strcmp(argv[3],"-n")) { fprintf(stdout, "[Error]: '-b' must be used as the first option && '-n' must be used as second the option\n"); fprintf(stdout, "For Example: %s -b 6 -n 4 -c 1 -w 0 -p 0 -s -r -d\n",APP_NAME); print_usage(); exit(1); } fd = open("/dev/mem", O_RDWR | O_SYNC); if(fd<0) { fprintf(stderr, "open /dev/mem error\n"); exit(1); } CLKBASE = mmap(NULL, (CLKREG_EndAddr-CLKREG_StartAddr), PROT_READ|PROT_WRITE, MAP_SHARED,fd, CLKREG_StartAddr & PAGE_MASK); if(CLKBASE == NULL || CLKBASE == MAP_FAILED) { fprintf(stderr, "[Error]: S3C2440 CLKCON base mmap error\n"); goto failed; } //fprintf(stdout, "Re-Maped 0x%X to Space Addr:0x%X, Maped Size 0x%X bytes\n",CLKREG_StartAddr,CLKBASE ,(CLKREG_EndAddr-CLKREG_StartAddr)); GpioBase = mmap(NULL, (GPIO_EndAddr-GPIO_StartAddr), PROT_READ|PROT_WRITE, MAP_SHARED,fd, GPIO_StartAddr & PAGE_MASK); if(GpioBase == NULL || GpioBase == MAP_FAILED) { fprintf(stderr, "S3C2440 gpio base mmap error\n"); goto failed; } //fprintf(stdout, "Re-Maped 0x%X to Space Addr:0x%X, Maped Size 0x%X\n",GPIO_StartAddr,GpioBase,(GPIO_EndAddr-GPIO_StartAddr)); s3c2440_clkcon_init(CLKBASE); while ((opt = getopt(argc, argv, "b: n: c: w: p: rsdh")) != -1) { switch (opt) { case 'b': /* Bank num to program */ Bank_num = strtoul(optarg, NULL, 0); if( Bank_num < 0 || Bank_num > 8){ fprintf(stderr, "[Error]: Please input correct Bank index num, the Bank index num should be 0--8 !\n"); goto failed; } Addr_offset = Bank_num * 0x10; if(Addr_offset==0x80) Addr_offset += 0x50; //fprintf(stdout,"The Addr_offset is 0x%X\n",Addr_offset); break; case 'n': /*GPIO num in Bank to program, GPIO num is the Mask bit*/ MaskBit = strtoul(optarg, NULL, 0); if( MaskBit < 0 || MaskBit > 25){ fprintf(stderr, "[Error]: Please input correct GPIO index num, the GPIO index num should be 0--25(max) !\n"); goto failed; } //fprintf(stdout,"The MaskBit is 0x%u\n",MaskBit); break; case 'c': /* The value to config the gpio_config_reg */ Function = strtoul(optarg, NULL, 0); if( Function < 0 || Function > 3){ fprintf(stderr, "[Error]: Please input correct 'Config_reg' value, the value should be 0x00--0x03 !\n"); goto failed; } if(Bank_num>0) { s3c2440_gpio_cfgpin(GpioBase,Addr_offset,MaskBit*2,Function); fprintf(stdout,"...Writing the 'Config_reg' to %s...\n",GPIOConStatus[Function]); } else { s3c2440_gpio_cfgpin(GpioBase,Addr_offset,MaskBit,Function); fprintf(stdout,"...Writing the 'Config_reg' to %s...\n",GPIOConStatus[Function+1]); } break; case 'w': /* The value to write to the gpio_data_reg*/ to = strtoul(optarg, NULL, 0); if( to < 0 || to > 1){ fprintf(stderr, "[Error]: Please input correct 'Data_reg' value, the value should be 0x00--0x01 !\n"); goto failed; } s3c2440_gpio_setpin(GpioBase, Addr_offset+4, MaskBit, to); fprintf(stdout,"...Writing the 'Data_reg' to %s...\n",GPIODataStatus[to]); break; case 'p': /* The value to write to the gpio_data_reg*/ pullup = strtoul(optarg, NULL, 0); if( pullup < 0 || pullup > 1){ fprintf(stderr, "[Error]: Please input correct 'Pullup_reg' value, the value should be 0x00--0x01 !\n"); goto failed; } if(Bank_num>0) { s3c2440_gpio_pullup(GpioBase, Addr_offset+8, MaskBit, pullup); fprintf(stdout,"...Writing the 'Pullup_reg' to %s...\n",GPIOPullupStatus[pullup]); } else fprintf(stderr,"[Error]: Can't set Pullup for GPIO Bank A%s\n"); break; case 'r': /* Read the value of the gpio_data_reg*/ fprintf(stdout,"The 'Data_reg' value is--> %s\n",GPIODataStatus[s3c2440_gpio_getpin(GpioBase, Addr_offset+4, MaskBit)]); break; case 's': /* Show the value of the gpio_configure_reg*/ if(Bank_num>0) fprintf(stdout,"The 'Config_reg' value is--> %s\n",GPIOConStatus[s3c2440_gpio_getcfg(GpioBase, Addr_offset, MaskBit*2)]); else fprintf(stdout,"The 'Config_reg' value is-->%s\n",GPIOConStatus[s3c2440_gpio_getcfg(GpioBase, Addr_offset, MaskBit)+1]); break; case 'd': /* Display the value of the pullup_reg*/ if(Bank_num>0) fprintf(stdout,"The 'Pullup_reg' value is--> %s\n",GPIOPullupStatus[s3c2440_gpio_getpull(GpioBase, Addr_offset+8, MaskBit)]); else fprintf(stderr,"[Error]: Can't get pullup status for GPIO Bank A\n"); break; case 'h': /* help information */ print_usage(); goto failed; default : fprintf(stderr, "[Error]: Uncompleted/Unknown option: %c\n", optopt); print_usage(); goto failed; } } } else { fprintf(stderr, "[Error]: The format of the input options is not correct!\n"); fprintf(stderr, "[Error]: The quantity of the input options is not correct!\n"); fprintf(stderr, "[Error]: Please use '%s -h' to get the help information!\n", APP_NAME); print_usage(); exit(1); } munmap(GpioBase,(GPIO_EndAddr-GPIO_StartAddr)); munmap(CLKBASE,(CLKREG_EndAddr-CLKREG_StartAddr)); close(fd); exit(0);failed: opt =-1; Bank_num = -1; Addr_offset = -1; MaskBit = -1; Function = -1, to = -1; pullup = -1; munmap(GpioBase,(GPIO_EndAddr-GPIO_StartAddr)); munmap(CLKBASE,(CLKREG_EndAddr-CLKREG_StartAddr)); close(fd); GpioBase = NULL; CLKBASE = NULL; exit(1);}
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